Merge commit 'v2.6.29-rc4' into sched/core

61 files changed, 2011 insertions, 840 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index e3ff2b9e602..33b7235f853 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1208,9 +1208,11 @@ static unsigned long vma_dump_size(struct vm_area_struct *vma,
 	 * check for an ELF header.  If we find one, dump the first page to
 	 * aid in determining what was mapped here.
 	 */
-	if (FILTER(ELF_HEADERS) && vma->vm_file != NULL && vma->vm_pgoff == 0) {
+	if (FILTER(ELF_HEADERS) &&
+	    vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
 		u32 __user *header = (u32 __user *) vma->vm_start;
 		u32 word;
+		mm_segment_t fs = get_fs();
 		/*
 		 * Doing it this way gets the constant folded by GCC.
 		 */
@@ -1223,7 +1225,15 @@ static unsigned long vma_dump_size(struct vm_area_struct *vma,
 		magic.elfmag[EI_MAG1] = ELFMAG1;
 		magic.elfmag[EI_MAG2] = ELFMAG2;
 		magic.elfmag[EI_MAG3] = ELFMAG3;
-		if (get_user(word, header) == 0 && word == magic.cmp)
+		/*
+		 * Switch to the user "segment" for get_user(),
+		 * then put back what elf_core_dump() had in place.
+		 */
+		set_fs(USER_DS);
+		if (unlikely(get_user(word, header)))
+			word = 0;
+		set_fs(fs);
+		if (word == magic.cmp)
 			return PAGE_SIZE;
 	}
 
diff --git a/fs/btrfs/Kconfig b/fs/btrfs/Kconfig
index f8fcf999ea1..7bb3c020e57 100644
--- a/fs/btrfs/Kconfig
+++ b/fs/btrfs/Kconfig
@@ -16,3 +16,16 @@ config BTRFS_FS
 	  module will be called btrfs.
 
 	  If unsure, say N.
+
+config BTRFS_FS_POSIX_ACL
+	bool "Btrfs POSIX Access Control Lists"
+	depends on BTRFS_FS
+	select FS_POSIX_ACL
+	help
+	  POSIX Access Control Lists (ACLs) support permissions for users and
+	  groups beyond the owner/group/world scheme.
+
+	  To learn more about Access Control Lists, visit the POSIX ACLs for
+	  Linux website <http://acl.bestbits.at/>.
+
+	  If you don't know what Access Control Lists are, say N
diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index 8e2fec05dbe..c84ca1f5259 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -16,11 +16,11 @@
  * Boston, MA 021110-1307, USA.
  */
 
-#include <linux/version.h>
 #include <linux/kthread.h>
 #include <linux/list.h>
 #include <linux/spinlock.h>
-# include <linux/freezer.h>
+#include <linux/freezer.h>
+#include <linux/ftrace.h>
 #include "async-thread.h"
 
 #define WORK_QUEUED_BIT 0
@@ -143,6 +143,7 @@ static int worker_loop(void *arg)
 	struct btrfs_work *work;
 	do {
 		spin_lock_irq(&worker->lock);
+again_locked:
 		while (!list_empty(&worker->pending)) {
 			cur = worker->pending.next;
 			work = list_entry(cur, struct btrfs_work, list);
@@ -165,14 +166,50 @@ static int worker_loop(void *arg)
 			check_idle_worker(worker);
 
 		}
-		worker->working = 0;
 		if (freezing(current)) {
+			worker->working = 0;
+			spin_unlock_irq(&worker->lock);
 			refrigerator();
 		} else {
-			set_current_state(TASK_INTERRUPTIBLE);
 			spin_unlock_irq(&worker->lock);
-			if (!kthread_should_stop())
+			if (!kthread_should_stop()) {
+				cpu_relax();
+				/*
+				 * we've dropped the lock, did someone else
+				 * jump_in?
+				 */
+				smp_mb();
+				if (!list_empty(&worker->pending))
+					continue;
+
+				/*
+				 * this short schedule allows more work to
+				 * come in without the queue functions
+				 * needing to go through wake_up_process()
+				 *
+				 * worker->working is still 1, so nobody
+				 * is going to try and wake us up
+				 */
+				schedule_timeout(1);
+				smp_mb();
+				if (!list_empty(&worker->pending))
+					continue;
+
+				/* still no more work?, sleep for real */
+				spin_lock_irq(&worker->lock);
+				set_current_state(TASK_INTERRUPTIBLE);
+				if (!list_empty(&worker->pending))
+					goto again_locked;
+
+				/*
+				 * this makes sure we get a wakeup when someone
+				 * adds something new to the queue
+				 */
+				worker->working = 0;
+				spin_unlock_irq(&worker->lock);
+
 				schedule();
+			}
 			__set_current_state(TASK_RUNNING);
 		}
 	} while (!kthread_should_stop());
@@ -350,13 +387,14 @@ int btrfs_requeue_work(struct btrfs_work *work)
 {
 	struct btrfs_worker_thread *worker = work->worker;
 	unsigned long flags;
+	int wake = 0;
 
 	if (test_and_set_bit(WORK_QUEUED_BIT, &work->flags))
 		goto out;
 
 	spin_lock_irqsave(&worker->lock, flags);
-	atomic_inc(&worker->num_pending);
 	list_add_tail(&work->list, &worker->pending);
+	atomic_inc(&worker->num_pending);
 
 	/* by definition we're busy, take ourselves off the idle
 	 * list
@@ -368,10 +406,16 @@ int btrfs_requeue_work(struct btrfs_work *work)
 			       &worker->workers->worker_list);
 		spin_unlock_irqrestore(&worker->workers->lock, flags);
 	}
+	if (!worker->working) {
+		wake = 1;
+		worker->working = 1;
+	}
 
 	spin_unlock_irqrestore(&worker->lock, flags);
-
+	if (wake)
+		wake_up_process(worker->task);
 out:
+
 	return 0;
 }
 
@@ -398,9 +442,10 @@ int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work)
 	}
 
 	spin_lock_irqsave(&worker->lock, flags);
+
+	list_add_tail(&work->list, &worker->pending);
 	atomic_inc(&worker->num_pending);
 	check_busy_worker(worker);
-	list_add_tail(&work->list, &worker->pending);
 
 	/*
 	 * avoid calling into wake_up_process if this thread has already
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index ee848d8585d..ab07627084f 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -32,7 +32,6 @@
 #include <linux/swap.h>
 #include <linux/writeback.h>
 #include <linux/bit_spinlock.h>
-#include <linux/version.h>
 #include <linux/pagevec.h>
 #include "compat.h"
 #include "ctree.h"
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 9e46c077681..551177c0011 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -54,6 +54,31 @@ struct btrfs_path *btrfs_alloc_path(void)
 	return path;
 }
 
+/*
+ * set all locked nodes in the path to blocking locks.  This should
+ * be done before scheduling
+ */
+noinline void btrfs_set_path_blocking(struct btrfs_path *p)
+{
+	int i;
+	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
+		if (p->nodes[i] && p->locks[i])
+			btrfs_set_lock_blocking(p->nodes[i]);
+	}
+}
+
+/*
+ * reset all the locked nodes in the patch to spinning locks.
+ */
+noinline void btrfs_clear_path_blocking(struct btrfs_path *p)
+{
+	int i;
+	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
+		if (p->nodes[i] && p->locks[i])
+			btrfs_clear_lock_blocking(p->nodes[i]);
+	}
+}
+
 /* this also releases the path */
 void btrfs_free_path(struct btrfs_path *p)
 {
@@ -272,6 +297,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 	if (IS_ERR(cow))
 		return PTR_ERR(cow);
 
+	/* cow is set to blocking by btrfs_init_new_buffer */
+
 	copy_extent_buffer(cow, buf, 0, 0, cow->len);
 	btrfs_set_header_bytenr(cow, cow->start);
 	btrfs_set_header_generation(cow, trans->transid);
@@ -388,17 +415,20 @@ noinline int btrfs_cow_block(struct btrfs_trans_handle *trans,
 		WARN_ON(1);
 	}
 
-	spin_lock(&root->fs_info->hash_lock);
 	if (btrfs_header_generation(buf) == trans->transid &&
 	    btrfs_header_owner(buf) == root->root_key.objectid &&
 	    !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
 		*cow_ret = buf;
-		spin_unlock(&root->fs_info->hash_lock);
 		WARN_ON(prealloc_dest);
 		return 0;
 	}
-	spin_unlock(&root->fs_info->hash_lock);
+
 	search_start = buf->start & ~((u64)(1024 * 1024 * 1024) - 1);
+
+	if (parent)
+		btrfs_set_lock_blocking(parent);
+	btrfs_set_lock_blocking(buf);
+
 	ret = __btrfs_cow_block(trans, root, buf, parent,
 				 parent_slot, cow_ret, search_start, 0,
 				 prealloc_dest);
@@ -504,6 +534,8 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 	if (parent_nritems == 1)
 		return 0;
 
+	btrfs_set_lock_blocking(parent);
+
 	for (i = start_slot; i < end_slot; i++) {
 		int close = 1;
 
@@ -564,6 +596,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 			search_start = last_block;
 
 		btrfs_tree_lock(cur);
+		btrfs_set_lock_blocking(cur);
 		err = __btrfs_cow_block(trans, root, cur, parent, i,
 					&cur, search_start,
 					min(16 * blocksize,
@@ -862,6 +895,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		return 0;
 
 	mid = path->nodes[level];
+
 	WARN_ON(!path->locks[level]);
 	WARN_ON(btrfs_header_generation(mid) != trans->transid);
 
@@ -884,6 +918,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 		/* promote the child to a root */
 		child = read_node_slot(root, mid, 0);
 		btrfs_tree_lock(child);
+		btrfs_set_lock_blocking(child);
 		BUG_ON(!child);
 		ret = btrfs_cow_block(trans, root, child, mid, 0, &child, 0);
 		BUG_ON(ret);
@@ -900,6 +935,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 
 		add_root_to_dirty_list(root);
 		btrfs_tree_unlock(child);
+
 		path->locks[level] = 0;
 		path->nodes[level] = NULL;
 		clean_tree_block(trans, root, mid);
@@ -924,6 +960,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 	left = read_node_slot(root, parent, pslot - 1);
 	if (left) {
 		btrfs_tree_lock(left);
+		btrfs_set_lock_blocking(left);
 		wret = btrfs_cow_block(trans, root, left,
 				       parent, pslot - 1, &left, 0);
 		if (wret) {
@@ -934,6 +971,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 	right = read_node_slot(root, parent, pslot + 1);
 	if (right) {
 		btrfs_tree_lock(right);
+		btrfs_set_lock_blocking(right);
 		wret = btrfs_cow_block(trans, root, right,
 				       parent, pslot + 1, &right, 0);
 		if (wret) {
@@ -1109,6 +1147,8 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 		u32 left_nr;
 
 		btrfs_tree_lock(left);
+		btrfs_set_lock_blocking(left);
+
 		left_nr = btrfs_header_nritems(left);
 		if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
 			wret = 1;
@@ -1155,7 +1195,10 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 	 */
 	if (right) {
 		u32 right_nr;
+
 		btrfs_tree_lock(right);
+		btrfs_set_lock_blocking(right);
+
 		right_nr = btrfs_header_nritems(right);
 		if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
 			wret = 1;
@@ -1210,8 +1253,7 @@ static noinline void reada_for_search(struct btrfs_root *root,
 	struct btrfs_disk_key disk_key;
 	u32 nritems;
 	u64 search;
-	u64 lowest_read;
-	u64 highest_read;
+	u64 target;
 	u64 nread = 0;
 	int direction = path->reada;
 	struct extent_buffer *eb;
@@ -1235,8 +1277,7 @@ static noinline void reada_for_search(struct btrfs_root *root,
 		return;
 	}
 
-	highest_read = search;
-	lowest_read = search;
+	target = search;
 
 	nritems = btrfs_header_nritems(node);
 	nr = slot;
@@ -1256,27 +1297,80 @@ static noinline void reada_for_search(struct btrfs_root *root,
 				break;
 		}
 		search = btrfs_node_blockptr(node, nr);
-		if ((search >= lowest_read && search <= highest_read) ||
-		    (search < lowest_read && lowest_read - search <= 16384) ||
-		    (search > highest_read && search - highest_read <= 16384)) {
+		if ((search <= target && target - search <= 65536) ||
+		    (search > target && search - target <= 65536)) {
 			readahead_tree_block(root, search, blocksize,
 				     btrfs_node_ptr_generation(node, nr));
 			nread += blocksize;
 		}
 		nscan++;
-		if (path->reada < 2 && (nread > (64 * 1024) || nscan > 32))
+		if ((nread > 65536 || nscan > 32))
 			break;
+	}
+}
 
-		if (nread > (256 * 1024) || nscan > 128)
-			break;
+/*
+ * returns -EAGAIN if it had to drop the path, or zero if everything was in
+ * cache
+ */
+static noinline int reada_for_balance(struct btrfs_root *root,
+				      struct btrfs_path *path, int level)
+{
+	int slot;
+	int nritems;
+	struct extent_buffer *parent;
+	struct extent_buffer *eb;
+	u64 gen;
+	u64 block1 = 0;
+	u64 block2 = 0;
+	int ret = 0;
+	int blocksize;
 
-		if (search < lowest_read)
-			lowest_read = search;
-		if (search > highest_read)
-			highest_read = search;
+	parent = path->nodes[level - 1];
+	if (!parent)
+		return 0;
+
+	nritems = btrfs_header_nritems(parent);
+	slot = path->slots[level];
+	blocksize = btrfs_level_size(root, level);
+
+	if (slot > 0) {
+		block1 = btrfs_node_blockptr(parent, slot - 1);
+		gen = btrfs_node_ptr_generation(parent, slot - 1);
+		eb = btrfs_find_tree_block(root, block1, blocksize);
+		if (eb && btrfs_buffer_uptodate(eb, gen))
+			block1 = 0;
+		free_extent_buffer(eb);
+	}
+	if (slot < nritems) {
+		block2 = btrfs_node_blockptr(parent, slot + 1);
+		gen = btrfs_node_ptr_generation(parent, slot + 1);
+		eb = btrfs_find_tree_block(root, block2, blocksize);
+		if (eb && btrfs_buffer_uptodate(eb, gen))
+			block2 = 0;
+		free_extent_buffer(eb);
+	}
+	if (block1 || block2) {
+		ret = -EAGAIN;
+		btrfs_release_path(root, path);
+		if (block1)
+			readahead_tree_block(root, block1, blocksize, 0);
+		if (block2)
+			readahead_tree_block(root, block2, blocksize, 0);
+
+		if (block1) {
+			eb = read_tree_block(root, block1, blocksize, 0);
+			free_extent_buffer(eb);
+		}
+		if (block1) {
+			eb = read_tree_block(root, block2, blocksize, 0);
+			free_extent_buffer(eb);
+		}
 	}
+	return ret;
 }
 
+
 /*
  * when we walk down the tree, it is usually safe to unlock the higher layers
  * in the tree.  The exceptions are when our path goes through slot 0, because
@@ -1328,6 +1422,32 @@ static noinline void unlock_up(struct btrfs_path *path, int level,
 }
 
 /*
+ * This releases any locks held in the path starting at level and
+ * going all the way up to the root.
+ *
+ * btrfs_search_slot will keep the lock held on higher nodes in a few
+ * corner cases, such as COW of the block at slot zero in the node.  This
+ * ignores those rules, and it should only be called when there are no
+ * more updates to be done higher up in the tree.
+ */
+noinline void btrfs_unlock_up_safe(struct btrfs_path *path, int level)
+{
+	int i;
+
+	if (path->keep_locks || path->lowest_level)
+		return;
+
+	for (i = level; i < BTRFS_MAX_LEVEL; i++) {
+		if (!path->nodes[i])
+			continue;
+		if (!path->locks[i])
+			continue;
+		btrfs_tree_unlock(path->nodes[i]);
+		path->locks[i] = 0;
+	}
+}
+
+/*
  * look for key in the tree.  path is filled in with nodes along the way
  * if key is found, we return zero and you can find the item in the leaf
  * level of the path (level 0)
@@ -1387,31 +1507,30 @@ again:
 			int wret;
 
 			/* is a cow on this block not required */
-			spin_lock(&root->fs_info->hash_lock);
 			if (btrfs_header_generation(b) == trans->transid &&
 			    btrfs_header_owner(b) == root->root_key.objectid &&
 			    !btrfs_header_flag(b, BTRFS_HEADER_FLAG_WRITTEN)) {
-				spin_unlock(&root->fs_info->hash_lock);
 				goto cow_done;
 			}
-			spin_unlock(&root->fs_info->hash_lock);
 
 			/* ok, we have to cow, is our old prealloc the right
 			 * size?
 			 */
 			if (prealloc_block.objectid &&
 			    prealloc_block.offset != b->len) {
+				btrfs_release_path(root, p);
 				btrfs_free_reserved_extent(root,
 					   prealloc_block.objectid,
 					   prealloc_block.offset);
 				prealloc_block.objectid = 0;
+				goto again;
 			}
 
 			/*
 			 * for higher level blocks, try not to allocate blocks
 			 * with the block and the parent locks held.
 			 */
-			if (level > 1 && !prealloc_block.objectid &&
+			if (level > 0 && !prealloc_block.objectid &&
 			    btrfs_path_lock_waiting(p, level)) {
 				u32 size = b->len;
 				u64 hint = b->start;
@@ -1425,6 +1544,8 @@ again:
 				goto again;
 			}
 
+			btrfs_set_path_blocking(p);
+
 			wret = btrfs_cow_block(trans, root, b,
 					       p->nodes[level + 1],
 					       p->slots[level + 1],
@@ -1446,6 +1567,22 @@ cow_done:
 		if (!p->skip_locking)
 			p->locks[level] = 1;
 
+		btrfs_clear_path_blocking(p);
+
+		/*
+		 * we have a lock on b and as long as we aren't changing
+		 * the tree, there is no way to for the items in b to change.
+		 * It is safe to drop the lock on our parent before we
+		 * go through the expensive btree search on b.
+		 *
+		 * If cow is true, then we might be changing slot zero,
+		 * which may require changing the parent.  So, we can't
+		 * drop the lock until after we know which slot we're
+		 * operating on.
+		 */
+		if (!cow)
+			btrfs_unlock_up_safe(p, level + 1);
+
 		ret = check_block(root, p, level);
 		if (ret) {
 			ret = -1;
@@ -1453,6 +1590,7 @@ cow_done:
 		}
 
 		ret = bin_search(b, key, level, &slot);
+
 		if (level != 0) {
 			if (ret && slot > 0)
 				slot -= 1;
@@ -1460,7 +1598,16 @@ cow_done:
 			if ((p->search_for_split || ins_len > 0) &&
 			    btrfs_header_nritems(b) >=
 			    BTRFS_NODEPTRS_PER_BLOCK(root) - 3) {
-				int sret = split_node(trans, root, p, level);
+				int sret;
+
+				sret = reada_for_balance(root, p, level);
+				if (sret)
+					goto again;
+
+				btrfs_set_path_blocking(p);
+				sret = split_node(trans, root, p, level);
+				btrfs_clear_path_blocking(p);
+
 				BUG_ON(sret > 0);
 				if (sret) {
 					ret = sret;
@@ -1468,9 +1615,19 @@ cow_done:
 				}
 				b = p->nodes[level];
 				slot = p->slots[level];
-			} else if (ins_len < 0) {
-				int sret = balance_level(trans, root, p,
-							 level);
+			} else if (ins_len < 0 &&
+				   btrfs_header_nritems(b) <
+				   BTRFS_NODEPTRS_PER_BLOCK(root) / 4) {
+				int sret;
+
+				sret = reada_for_balance(root, p, level);
+				if (sret)
+					goto again;
+
+				btrfs_set_path_blocking(p);
+				sret = balance_level(trans, root, p, level);
+				btrfs_clear_path_blocking(p);
+
 				if (sret) {
 					ret = sret;
 					goto done;
@@ -1504,7 +1661,7 @@ cow_done:
 				 * of the btree by dropping locks before
 				 * we read.
 				 */
-				if (level > 1) {
+				if (level > 0) {
 					btrfs_release_path(NULL, p);
 					if (tmp)
 						free_extent_buffer(tmp);
@@ -1519,6 +1676,7 @@ cow_done:
 						free_extent_buffer(tmp);
 					goto again;
 				} else {
+					btrfs_set_path_blocking(p);
 					if (tmp)
 						free_extent_buffer(tmp);
 					if (should_reada)
@@ -1528,14 +1686,29 @@ cow_done:
 					b = read_node_slot(root, b, slot);
 				}
 			}
-			if (!p->skip_locking)
-				btrfs_tree_lock(b);
+			if (!p->skip_locking) {
+				int lret;
+
+				btrfs_clear_path_blocking(p);
+				lret = btrfs_try_spin_lock(b);
+
+				if (!lret) {
+					btrfs_set_path_blocking(p);
+					btrfs_tree_lock(b);
+					btrfs_clear_path_blocking(p);
+				}
+			}
 		} else {
 			p->slots[level] = slot;
 			if (ins_len > 0 &&
 			    btrfs_leaf_free_space(root, b) < ins_len) {
-				int sret = split_leaf(trans, root, key,
+				int sret;
+
+				btrfs_set_path_blocking(p);
+				sret = split_leaf(trans, root, key,
 						      p, ins_len, ret == 0);
+				btrfs_clear_path_blocking(p);
+
 				BUG_ON(sret > 0);
 				if (sret) {
 					ret = sret;
@@ -1549,12 +1722,16 @@ cow_done:
 	}
 	ret = 1;
 done:
+	/*
+	 * we don't really know what they plan on doing with the path
+	 * from here on, so for now just mark it as blocking
+	 */
+	btrfs_set_path_blocking(p);
 	if (prealloc_block.objectid) {
 		btrfs_free_reserved_extent(root,
 			   prealloc_block.objectid,
 			   prealloc_block.offset);
 	}
-
 	return ret;
 }
 
@@ -1578,6 +1755,8 @@ int btrfs_merge_path(struct btrfs_trans_handle *trans,
 	ret = btrfs_cow_block(trans, root, eb, NULL, 0, &eb, 0);
 	BUG_ON(ret);
 
+	btrfs_set_lock_blocking(eb);
+
 	parent = eb;
 	while (1) {
 		level = btrfs_header_level(parent);
@@ -1602,6 +1781,7 @@ int btrfs_merge_path(struct btrfs_trans_handle *trans,
 			eb = read_tree_block(root, bytenr, blocksize,
 					     generation);
 			btrfs_tree_lock(eb);
+			btrfs_set_lock_blocking(eb);
 		}
 
 		/*
@@ -1626,6 +1806,7 @@ int btrfs_merge_path(struct btrfs_trans_handle *trans,
 				eb = read_tree_block(root, bytenr, blocksize,
 						generation);
 				btrfs_tree_lock(eb);
+				btrfs_set_lock_blocking(eb);
 			}
 
 			ret = btrfs_cow_block(trans, root, eb, parent, slot,
@@ -2172,6 +2353,8 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
 
 	right = read_node_slot(root, upper, slot + 1);
 	btrfs_tree_lock(right);
+	btrfs_set_lock_blocking(right);
+
 	free_space = btrfs_leaf_free_space(root, right);
 	if (free_space < data_size)
 		goto out_unlock;
@@ -2367,6 +2550,8 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
 
 	left = read_node_slot(root, path->nodes[1], slot - 1);
 	btrfs_tree_lock(left);
+	btrfs_set_lock_blocking(left);
+
 	free_space = btrfs_leaf_free_space(root, left);
 	if (free_space < data_size) {
 		ret = 1;
@@ -2825,6 +3010,12 @@ int btrfs_split_item(struct btrfs_trans_handle *trans,
 	path->keep_locks = 0;
 	BUG_ON(ret);
 
+	/*
+	 * make sure any changes to the path from split_leaf leave it
+	 * in a blocking state
+	 */
+	btrfs_set_path_blocking(path);
+
 	leaf = path->nodes[0];
 	BUG_ON(btrfs_leaf_free_space(root, leaf) < sizeof(struct btrfs_item));
 
@@ -3354,6 +3545,7 @@ int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
 		BUG();
 	}
 out:
+	btrfs_unlock_up_safe(path, 1);
 	return ret;
 }
 
@@ -3441,15 +3633,22 @@ noinline int btrfs_del_leaf(struct btrfs_trans_handle *trans,
 {
 	int ret;
 	u64 root_gen = btrfs_header_generation(path->nodes[1]);
+	u64 parent_start = path->nodes[1]->start;
+	u64 parent_owner = btrfs_header_owner(path->nodes[1]);
 
 	ret = del_ptr(trans, root, path, 1, path->slots[1]);
 	if (ret)
 		return ret;
 
+	/*
+	 * btrfs_free_extent is expensive, we want to make sure we
+	 * aren't holding any locks when we call it
+	 */
+	btrfs_unlock_up_safe(path, 0);
+
 	ret = btrfs_free_extent(trans, root, bytenr,
 				btrfs_level_size(root, 0),
-				path->nodes[1]->start,
-				btrfs_header_owner(path->nodes[1]),
+				parent_start, parent_owner,
 				root_gen, 0, 1);
 	return ret;
 }
@@ -3721,12 +3920,14 @@ find_next_key:
 		 */
 		if (slot >= nritems) {
 			path->slots[level] = slot;
+			btrfs_set_path_blocking(path);
 			sret = btrfs_find_next_key(root, path, min_key, level,
 						  cache_only, min_trans);
 			if (sret == 0) {
 				btrfs_release_path(root, path);
 				goto again;
 			} else {
+				btrfs_clear_path_blocking(path);
 				goto out;
 			}
 		}
@@ -3738,16 +3939,20 @@ find_next_key:
 			unlock_up(path, level, 1);
 			goto out;
 		}
+		btrfs_set_path_blocking(path);
 		cur = read_node_slot(root, cur, slot);
 
 		btrfs_tree_lock(cur);
+
 		path->locks[level - 1] = 1;
 		path->nodes[level - 1] = cur;
 		unlock_up(path, level, 1);
+		btrfs_clear_path_blocking(path);
 	}
 out:
 	if (ret == 0)
 		memcpy(min_key, &found_key, sizeof(found_key));
+	btrfs_set_path_blocking(path);
 	return ret;
 }
 
@@ -3843,6 +4048,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 	if (ret < 0)
 		return ret;
 
+	btrfs_set_path_blocking(path);
 	nritems = btrfs_header_nritems(path->nodes[0]);
 	/*
 	 * by releasing the path above we dropped all our locks.  A balance
@@ -3873,6 +4079,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 			free_extent_buffer(next);
 		}
 
+		/* the path was set to blocking above */
 		if (level == 1 && (path->locks[1] || path->skip_locking) &&
 		    path->reada)
 			reada_for_search(root, path, level, slot, 0);
@@ -3881,6 +4088,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 		if (!path->skip_locking) {
 			WARN_ON(!btrfs_tree_locked(c));
 			btrfs_tree_lock(next);
+			btrfs_set_lock_blocking(next);
 		}
 		break;
 	}
@@ -3897,12 +4105,15 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 			path->locks[level] = 1;
 		if (!level)
 			break;
+
+		btrfs_set_path_blocking(path);
 		if (level == 1 && path->locks[1] && path->reada)
 			reada_for_search(root, path, level, slot, 0);
 		next = read_node_slot(root, next, 0);
 		if (!path->skip_locking) {
 			WARN_ON(!btrfs_tree_locked(path->nodes[level]));
 			btrfs_tree_lock(next);
+			btrfs_set_lock_blocking(next);
 		}
 	}
 done:
@@ -3927,6 +4138,7 @@ int btrfs_previous_item(struct btrfs_root *root,
 
 	while (1) {
 		if (path->slots[0] == 0) {
+			btrfs_set_path_blocking(path);
 			ret = btrfs_prev_leaf(root, path);
 			if (ret != 0)
 				return ret;
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index eee060f8811..531db112c8b 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -454,17 +454,11 @@ struct btrfs_timespec {
 	__le32 nsec;
 } __attribute__ ((__packed__));
 
-typedef enum {
+enum btrfs_compression_type {
 	BTRFS_COMPRESS_NONE = 0,
 	BTRFS_COMPRESS_ZLIB = 1,
 	BTRFS_COMPRESS_LAST = 2,
-} btrfs_compression_type;
-
-/* we don't understand any encryption methods right now */
-typedef enum {
-	BTRFS_ENCRYPTION_NONE = 0,
-	BTRFS_ENCRYPTION_LAST = 1,
-} btrfs_encryption_type;
+};
 
 struct btrfs_inode_item {
 	/* nfs style generation number */
@@ -701,9 +695,7 @@ struct btrfs_fs_info {
 	struct btrfs_transaction *running_transaction;
 	wait_queue_head_t transaction_throttle;
 	wait_queue_head_t transaction_wait;
-
 	wait_queue_head_t async_submit_wait;
-	wait_queue_head_t tree_log_wait;
 
 	struct btrfs_super_block super_copy;
 	struct btrfs_super_block super_for_commit;
@@ -711,7 +703,6 @@ struct btrfs_fs_info {
 	struct super_block *sb;
 	struct inode *btree_inode;
 	struct backing_dev_info bdi;
-	spinlock_t hash_lock;
 	struct mutex trans_mutex;
 	struct mutex tree_log_mutex;
 	struct mutex transaction_kthread_mutex;
@@ -730,10 +721,6 @@ struct btrfs_fs_info {
 	atomic_t async_submit_draining;
 	atomic_t nr_async_bios;
 	atomic_t async_delalloc_pages;
-	atomic_t tree_log_writers;
-	atomic_t tree_log_commit;
-	unsigned long tree_log_batch;
-	u64 tree_log_transid;
 
 	/*
 	 * this is used by the balancing code to wait for all the pending
@@ -833,7 +820,14 @@ struct btrfs_root {
 	struct kobject root_kobj;
 	struct completion kobj_unregister;
 	struct mutex objectid_mutex;
+
 	struct mutex log_mutex;
+	wait_queue_head_t log_writer_wait;
+	wait_queue_head_t log_commit_wait[2];
+	atomic_t log_writers;
+	atomic_t log_commit[2];
+	unsigned long log_transid;
+	unsigned long log_batch;
 
 	u64 objectid;
 	u64 last_trans;
@@ -1841,6 +1835,10 @@ void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
 struct btrfs_path *btrfs_alloc_path(void);
 void btrfs_free_path(struct btrfs_path *p);
 void btrfs_init_path(struct btrfs_path *p);
+void btrfs_set_path_blocking(struct btrfs_path *p);
+void btrfs_clear_path_blocking(struct btrfs_path *p);
+void btrfs_unlock_up_safe(struct btrfs_path *p, int level);
+
 int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		   struct btrfs_path *path, int slot, int nr);
 int btrfs_del_leaf(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 81a313874ae..5aebddd7119 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -16,7 +16,6 @@
  * Boston, MA 021110-1307, USA.
  */
 
-#include <linux/version.h>
 #include <linux/fs.h>
 #include <linux/blkdev.h>
 #include <linux/scatterlist.h>
@@ -800,7 +799,7 @@ struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 	ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
 
 	if (ret == 0)
-		buf->flags |= EXTENT_UPTODATE;
+		set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
 	else
 		WARN_ON(1);
 	return buf;
@@ -814,6 +813,10 @@ int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 	if (btrfs_header_generation(buf) ==
 	    root->fs_info->running_transaction->transid) {
 		WARN_ON(!btrfs_tree_locked(buf));
+
+		/* ugh, clear_extent_buffer_dirty can be expensive */
+		btrfs_set_lock_blocking(buf);
+
 		clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
 					  buf);
 	}
@@ -850,6 +853,14 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 	spin_lock_init(&root->list_lock);
 	mutex_init(&root->objectid_mutex);
 	mutex_init(&root->log_mutex);
+	init_waitqueue_head(&root->log_writer_wait);
+	init_waitqueue_head(&root->log_commit_wait[0]);
+	init_waitqueue_head(&root->log_commit_wait[1]);
+	atomic_set(&root->log_commit[0], 0);
+	atomic_set(&root->log_commit[1], 0);
+	atomic_set(&root->log_writers, 0);
+	root->log_batch = 0;
+	root->log_transid = 0;
 	extent_io_tree_init(&root->dirty_log_pages,
 			     fs_info->btree_inode->i_mapping, GFP_NOFS);
 
@@ -934,15 +945,16 @@ int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans,
 	return 0;
 }
 
-int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
-			     struct btrfs_fs_info *fs_info)
+static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
+					 struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_root *root;
 	struct btrfs_root *tree_root = fs_info->tree_root;
+	struct extent_buffer *leaf;
 
 	root = kzalloc(sizeof(*root), GFP_NOFS);
 	if (!root)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
 	__setup_root(tree_root->nodesize, tree_root->leafsize,
 		     tree_root->sectorsize, tree_root->stripesize,
@@ -951,12 +963,23 @@ int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 	root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
 	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
 	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
+	/*
+	 * log trees do not get reference counted because they go away
+	 * before a real commit is actually done.  They do store pointers
+	 * to file data extents, and those reference counts still get
+	 * updated (along with back refs to the log tree).
+	 */
 	root->ref_cows = 0;
 
-	root->node = btrfs_alloc_free_block(trans, root, root->leafsize,
-					    0, BTRFS_TREE_LOG_OBJECTID,
-					    trans->transid, 0, 0, 0);
+	leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
+				      0, BTRFS_TREE_LOG_OBJECTID,
+				      trans->transid, 0, 0, 0);
+	if (IS_ERR(leaf)) {
+		kfree(root);
+		return ERR_CAST(leaf);
+	}
 
+	root->node = leaf;
 	btrfs_set_header_nritems(root->node, 0);
 	btrfs_set_header_level(root->node, 0);
 	btrfs_set_header_bytenr(root->node, root->node->start);
@@ -968,7 +991,48 @@ int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 			    BTRFS_FSID_SIZE);
 	btrfs_mark_buffer_dirty(root->node);
 	btrfs_tree_unlock(root->node);
-	fs_info->log_root_tree = root;
+	return root;
+}
+
+int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
+			     struct btrfs_fs_info *fs_info)
+{
+	struct btrfs_root *log_root;
+
+	log_root = alloc_log_tree(trans, fs_info);
+	if (IS_ERR(log_root))
+		return PTR_ERR(log_root);
+	WARN_ON(fs_info->log_root_tree);
+	fs_info->log_root_tree = log_root;
+	return 0;
+}
+
+int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
+		       struct btrfs_root *root)
+{
+	struct btrfs_root *log_root;
+	struct btrfs_inode_item *inode_item;
+
+	log_root = alloc_log_tree(trans, root->fs_info);
+	if (IS_ERR(log_root))
+		return PTR_ERR(log_root);
+
+	log_root->last_trans = trans->transid;
+	log_root->root_key.offset = root->root_key.objectid;
+
+	inode_item = &log_root->root_item.inode;
+	inode_item->generation = cpu_to_le64(1);
+	inode_item->size = cpu_to_le64(3);
+	inode_item->nlink = cpu_to_le32(1);
+	inode_item->nbytes = cpu_to_le64(root->leafsize);
+	inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
+
+	btrfs_set_root_bytenr(&log_root->root_item, log_root->node->start);
+	btrfs_set_root_generation(&log_root->root_item, trans->transid);
+
+	WARN_ON(root->log_root);
+	root->log_root = log_root;
+	root->log_transid = 0;
 	return 0;
 }
 
@@ -1136,7 +1200,6 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 {
 	struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
 	int ret = 0;
-	struct list_head *cur;
 	struct btrfs_device *device;
 	struct backing_dev_info *bdi;
 #if 0
@@ -1144,8 +1207,7 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 	    btrfs_congested_async(info, 0))
 		return 1;
 #endif
-	list_for_each(cur, &info->fs_devices->devices) {
-		device = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
 		if (!device->bdev)
 			continue;
 		bdi = blk_get_backing_dev_info(device->bdev);
@@ -1163,13 +1225,11 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
  */
 static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
 {
-	struct list_head *cur;
 	struct btrfs_device *device;
 	struct btrfs_fs_info *info;
 
 	info = (struct btrfs_fs_info *)bdi->unplug_io_data;
-	list_for_each(cur, &info->fs_devices->devices) {
-		device = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
 		if (!device->bdev)
 			continue;
 
@@ -1447,7 +1507,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	INIT_LIST_HEAD(&fs_info->dead_roots);
 	INIT_LIST_HEAD(&fs_info->hashers);
 	INIT_LIST_HEAD(&fs_info->delalloc_inodes);
-	spin_lock_init(&fs_info->hash_lock);
 	spin_lock_init(&fs_info->delalloc_lock);
 	spin_lock_init(&fs_info->new_trans_lock);
 	spin_lock_init(&fs_info->ref_cache_lock);
@@ -1535,10 +1594,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	init_waitqueue_head(&fs_info->transaction_throttle);
 	init_waitqueue_head(&fs_info->transaction_wait);
 	init_waitqueue_head(&fs_info->async_submit_wait);
-	init_waitqueue_head(&fs_info->tree_log_wait);
-	atomic_set(&fs_info->tree_log_commit, 0);
-	atomic_set(&fs_info->tree_log_writers, 0);
-	fs_info->tree_log_transid = 0;
 
 	__setup_root(4096, 4096, 4096, 4096, tree_root,
 		     fs_info, BTRFS_ROOT_TREE_OBJECTID);
@@ -1627,6 +1682,8 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	 * low idle thresh
 	 */
 	fs_info->endio_workers.idle_thresh = 4;
+	fs_info->endio_meta_workers.idle_thresh = 4;
+
 	fs_info->endio_write_workers.idle_thresh = 64;
 	fs_info->endio_meta_write_workers.idle_thresh = 64;
 
@@ -1740,13 +1797,13 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
 	fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
 					       "btrfs-cleaner");
-	if (!fs_info->cleaner_kthread)
+	if (IS_ERR(fs_info->cleaner_kthread))
 		goto fail_csum_root;
 
 	fs_info->transaction_kthread = kthread_run(transaction_kthread,
 						   tree_root,
 						   "btrfs-transaction");
-	if (!fs_info->transaction_kthread)
+	if (IS_ERR(fs_info->transaction_kthread))
 		goto fail_cleaner;
 
 	if (btrfs_super_log_root(disk_super) != 0) {
@@ -1828,13 +1885,14 @@ fail_sb_buffer:
 fail_iput:
 	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
 	iput(fs_info->btree_inode);
-fail:
+
 	btrfs_close_devices(fs_info->fs_devices);
 	btrfs_mapping_tree_free(&fs_info->mapping_tree);
+	bdi_destroy(&fs_info->bdi);
 
+fail:
 	kfree(extent_root);
 	kfree(tree_root);
-	bdi_destroy(&fs_info->bdi);
 	kfree(fs_info);
 	kfree(chunk_root);
 	kfree(dev_root);
@@ -1995,7 +2053,6 @@ static int write_dev_supers(struct btrfs_device *device,
 
 int write_all_supers(struct btrfs_root *root, int max_mirrors)
 {
-	struct list_head *cur;
 	struct list_head *head = &root->fs_info->fs_devices->devices;
 	struct btrfs_device *dev;
 	struct btrfs_super_block *sb;
@@ -2011,8 +2068,7 @@ int write_all_supers(struct btrfs_root *root, int max_mirrors)
 
 	sb = &root->fs_info->super_for_commit;
 	dev_item = &sb->dev_item;
-	list_for_each(cur, head) {
-		dev = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(dev, head, dev_list) {
 		if (!dev->bdev) {
 			total_errors++;
 			continue;
@@ -2045,8 +2101,7 @@ int write_all_supers(struct btrfs_root *root, int max_mirrors)
 	}
 
 	total_errors = 0;
-	list_for_each(cur, head) {
-		dev = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(dev, head, dev_list) {
 		if (!dev->bdev)
 			continue;
 		if (!dev->in_fs_metadata || !dev->writeable)
@@ -2260,6 +2315,8 @@ void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 	u64 transid = btrfs_header_generation(buf);
 	struct inode *btree_inode = root->fs_info->btree_inode;
 
+	btrfs_set_lock_blocking(buf);
+
 	WARN_ON(!btrfs_tree_locked(buf));
 	if (transid != root->fs_info->generation) {
 		printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
@@ -2302,14 +2359,13 @@ int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
 	int ret;
 	ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
 	if (ret == 0)
-		buf->flags |= EXTENT_UPTODATE;
+		set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
 	return ret;
 }
 
 int btree_lock_page_hook(struct page *page)
 {
 	struct inode *inode = page->mapping->host;
-	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 	struct extent_buffer *eb;
 	unsigned long len;
@@ -2324,9 +2380,7 @@ int btree_lock_page_hook(struct page *page)
 		goto out;
 
 	btrfs_tree_lock(eb);
-	spin_lock(&root->fs_info->hash_lock);
 	btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
-	spin_unlock(&root->fs_info->hash_lock);
 	btrfs_tree_unlock(eb);
 	free_extent_buffer(eb);
 out:
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index c0ff404c31b..494a56eb298 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -98,5 +98,7 @@ int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans,
 			     struct btrfs_fs_info *fs_info);
 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 			     struct btrfs_fs_info *fs_info);
+int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
+		       struct btrfs_root *root);
 int btree_lock_page_hook(struct page *page);
 #endif
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 293da650873..7527523c2d2 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -19,7 +19,7 @@
 #include <linux/pagemap.h>
 #include <linux/writeback.h>
 #include <linux/blkdev.h>
-#include <linux/version.h>
+#include <linux/sort.h>
 #include "compat.h"
 #include "hash.h"
 #include "crc32c.h"
@@ -30,7 +30,6 @@
 #include "volumes.h"
 #include "locking.h"
 #include "ref-cache.h"
-#include "compat.h"
 
 #define PENDING_EXTENT_INSERT 0
 #define PENDING_EXTENT_DELETE 1
@@ -326,10 +325,8 @@ static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
 						  u64 flags)
 {
 	struct list_head *head = &info->space_info;
-	struct list_head *cur;
 	struct btrfs_space_info *found;
-	list_for_each(cur, head) {
-		found = list_entry(cur, struct btrfs_space_info, list);
+	list_for_each_entry(found, head, list) {
 		if (found->flags == flags)
 			return found;
 	}
@@ -1525,15 +1522,55 @@ out:
 	return ret;
 }
 
-int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-		  struct extent_buffer *orig_buf, struct extent_buffer *buf,
-		  u32 *nr_extents)
+/* when a block goes through cow, we update the reference counts of
+ * everything that block points to.  The internal pointers of the block
+ * can be in just about any order, and it is likely to have clusters of
+ * things that are close together and clusters of things that are not.
+ *
+ * To help reduce the seeks that come with updating all of these reference
+ * counts, sort them by byte number before actual updates are done.
+ *
+ * struct refsort is used to match byte number to slot in the btree block.
+ * we sort based on the byte number and then use the slot to actually
+ * find the item.
+ *
+ * struct refsort is smaller than strcut btrfs_item and smaller than
+ * struct btrfs_key_ptr.  Since we're currently limited to the page size
+ * for a btree block, there's no way for a kmalloc of refsorts for a
+ * single node to be bigger than a page.
+ */
+struct refsort {
+	u64 bytenr;
+	u32 slot;
+};
+
+/*
+ * for passing into sort()
+ */
+static int refsort_cmp(const void *a_void, const void *b_void)
+{
+	const struct refsort *a = a_void;
+	const struct refsort *b = b_void;
+
+	if (a->bytenr < b->bytenr)
+		return -1;
+	if (a->bytenr > b->bytenr)
+		return 1;
+	return 0;
+}
+
+
+noinline int btrfs_inc_ref(struct btrfs_trans_handle *trans,
+			   struct btrfs_root *root,
+			   struct extent_buffer *orig_buf,
+			   struct extent_buffer *buf, u32 *nr_extents)
 {
 	u64 bytenr;
 	u64 ref_root;
 	u64 orig_root;
 	u64 ref_generation;
 	u64 orig_generation;
+	struct refsort *sorted;
 	u32 nritems;
 	u32 nr_file_extents = 0;
 	struct btrfs_key key;
@@ -1542,6 +1579,8 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 	int level;
 	int ret = 0;
 	int faili = 0;
+	int refi = 0;
+	int slot;
 	int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
 			    u64, u64, u64, u64, u64, u64, u64, u64);
 
@@ -1553,6 +1592,9 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 	nritems = btrfs_header_nritems(buf);
 	level = btrfs_header_level(buf);
 
+	sorted = kmalloc(sizeof(struct refsort) * nritems, GFP_NOFS);
+	BUG_ON(!sorted);
+
 	if (root->ref_cows) {
 		process_func = __btrfs_inc_extent_ref;
 	} else {
@@ -1565,6 +1607,11 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		process_func = __btrfs_update_extent_ref;
 	}
 
+	/*
+	 * we make two passes through the items.  In the first pass we
+	 * only record the byte number and slot.  Then we sort based on
+	 * byte number and do the actual work based on the sorted results
+	 */
 	for (i = 0; i < nritems; i++) {
 		cond_resched();
 		if (level == 0) {
@@ -1581,6 +1628,32 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 				continue;
 
 			nr_file_extents++;
+			sorted[refi].bytenr = bytenr;
+			sorted[refi].slot = i;
+			refi++;
+		} else {
+			bytenr = btrfs_node_blockptr(buf, i);
+			sorted[refi].bytenr = bytenr;
+			sorted[refi].slot = i;
+			refi++;
+		}
+	}
+	/*
+	 * if refi == 0, we didn't actually put anything into the sorted
+	 * array and we're done
+	 */
+	if (refi == 0)
+		goto out;
+
+	sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL);
+
+	for (i = 0; i < refi; i++) {
+		cond_resched();
+		slot = sorted[i].slot;
+		bytenr = sorted[i].bytenr;
+
+		if (level == 0) {
+			btrfs_item_key_to_cpu(buf, &key, slot);
 
 			ret = process_func(trans, root, bytenr,
 					   orig_buf->start, buf->start,
@@ -1589,25 +1662,25 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 					   key.objectid);
 
 			if (ret) {
-				faili = i;
+				faili = slot;
 				WARN_ON(1);
 				goto fail;
 			}
 		} else {
-			bytenr = btrfs_node_blockptr(buf, i);
 			ret = process_func(trans, root, bytenr,
 					   orig_buf->start, buf->start,
 					   orig_root, ref_root,
 					   orig_generation, ref_generation,
 					   level - 1);
 			if (ret) {
-				faili = i;
+				faili = slot;
 				WARN_ON(1);
 				goto fail;
 			}
 		}
 	}
 out:
+	kfree(sorted);
 	if (nr_extents) {
 		if (level == 0)
 			*nr_extents = nr_file_extents;
@@ -1616,6 +1689,7 @@ out:
 	}
 	return 0;
 fail:
+	kfree(sorted);
 	WARN_ON(1);
 	return ret;
 }
@@ -2159,7 +2233,8 @@ again:
 		ret = find_first_extent_bit(&info->extent_ins, search, &start,
 					    &end, EXTENT_WRITEBACK);
 		if (ret) {
-			if (skipped && all && !num_inserts) {
+			if (skipped && all && !num_inserts &&
+			    list_empty(&update_list)) {
 				skipped = 0;
 				search = 0;
 				continue;
@@ -2547,6 +2622,7 @@ again:
 		if (ret) {
 			if (all && skipped && !nr) {
 				search = 0;
+				skipped = 0;
 				continue;
 			}
 			mutex_unlock(&info->extent_ins_mutex);
@@ -2700,13 +2776,9 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 	/* if metadata always pin */
 	if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
 		if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
-			struct btrfs_block_group_cache *cache;
-
-			/* btrfs_free_reserved_extent */
-			cache = btrfs_lookup_block_group(root->fs_info, bytenr);
-			BUG_ON(!cache);
-			btrfs_add_free_space(cache, bytenr, num_bytes);
-			put_block_group(cache);
+			mutex_lock(&root->fs_info->pinned_mutex);
+			btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
+			mutex_unlock(&root->fs_info->pinned_mutex);
 			update_reserved_extents(root, bytenr, num_bytes, 0);
 			return 0;
 		}
@@ -3014,7 +3086,6 @@ loop_check:
 static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
 {
 	struct btrfs_block_group_cache *cache;
-	struct list_head *l;
 
 	printk(KERN_INFO "space_info has %llu free, is %sfull\n",
 	       (unsigned long long)(info->total_bytes - info->bytes_used -
@@ -3022,8 +3093,7 @@ static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
 	       (info->full) ? "" : "not ");
 
 	down_read(&info->groups_sem);
-	list_for_each(l, &info->block_groups) {
-		cache = list_entry(l, struct btrfs_block_group_cache, list);
+	list_for_each_entry(cache, &info->block_groups, list) {
 		spin_lock(&cache->lock);
 		printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
 		       "%llu pinned %llu reserved\n",
@@ -3342,7 +3412,10 @@ struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
 	btrfs_set_header_generation(buf, trans->transid);
 	btrfs_tree_lock(buf);
 	clean_tree_block(trans, root, buf);
+
+	btrfs_set_lock_blocking(buf);
 	btrfs_set_buffer_uptodate(buf);
+
 	if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
 		set_extent_dirty(&root->dirty_log_pages, buf->start,
 			 buf->start + buf->len - 1, GFP_NOFS);
@@ -3351,6 +3424,7 @@ struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
 			 buf->start + buf->len - 1, GFP_NOFS);
 	}
 	trans->blocks_used++;
+	/* this returns a buffer locked for blocking */
 	return buf;
 }
 
@@ -3388,36 +3462,73 @@ int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
 {
 	u64 leaf_owner;
 	u64 leaf_generation;
+	struct refsort *sorted;
 	struct btrfs_key key;
 	struct btrfs_file_extent_item *fi;
 	int i;
 	int nritems;
 	int ret;
+	int refi = 0;
+	int slot;
 
 	BUG_ON(!btrfs_is_leaf(leaf));
 	nritems = btrfs_header_nritems(leaf);
 	leaf_owner = btrfs_header_owner(leaf);
 	leaf_generation = btrfs_header_generation(leaf);
 
+	sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS);
+	/* we do this loop twice.  The first time we build a list
+	 * of the extents we have a reference on, then we sort the list
+	 * by bytenr.  The second time around we actually do the
+	 * extent freeing.
+	 */
 	for (i = 0; i < nritems; i++) {
 		u64 disk_bytenr;
 		cond_resched();
 
 		btrfs_item_key_to_cpu(leaf, &key, i);
+
+		/* only extents have references, skip everything else */
 		if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
 			continue;
+
 		fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
+
+		/* inline extents live in the btree, they don't have refs */
 		if (btrfs_file_extent_type(leaf, fi) ==
 		    BTRFS_FILE_EXTENT_INLINE)
 			continue;
-		/*
-		 * FIXME make sure to insert a trans record that
-		 * repeats the snapshot del on crash
-		 */
+
 		disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
+
+		/* holes don't have refs */
 		if (disk_bytenr == 0)
 			continue;
 
+		sorted[refi].bytenr = disk_bytenr;
+		sorted[refi].slot = i;
+		refi++;
+	}
+
+	if (refi == 0)
+		goto out;
+
+	sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL);
+
+	for (i = 0; i < refi; i++) {
+		u64 disk_bytenr;
+
+		disk_bytenr = sorted[i].bytenr;
+		slot = sorted[i].slot;
+
+		cond_resched();
+
+		btrfs_item_key_to_cpu(leaf, &key, slot);
+		if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
+			continue;
+
+		fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
+
 		ret = __btrfs_free_extent(trans, root, disk_bytenr,
 				btrfs_file_extent_disk_num_bytes(leaf, fi),
 				leaf->start, leaf_owner, leaf_generation,
@@ -3428,6 +3539,8 @@ int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
 		wake_up(&root->fs_info->transaction_throttle);
 		cond_resched();
 	}
+out:
+	kfree(sorted);
 	return 0;
 }
 
@@ -3437,9 +3550,25 @@ static noinline int cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
 {
 	int i;
 	int ret;
-	struct btrfs_extent_info *info = ref->extents;
+	struct btrfs_extent_info *info;
+	struct refsort *sorted;
+
+	if (ref->nritems == 0)
+		return 0;
 
+	sorted = kmalloc(sizeof(*sorted) * ref->nritems, GFP_NOFS);
 	for (i = 0; i < ref->nritems; i++) {
+		sorted[i].bytenr = ref->extents[i].bytenr;
+		sorted[i].slot = i;
+	}
+	sort(sorted, ref->nritems, sizeof(struct refsort), refsort_cmp, NULL);
+
+	/*
+	 * the items in the ref were sorted when the ref was inserted
+	 * into the ref cache, so this is already in order
+	 */
+	for (i = 0; i < ref->nritems; i++) {
+		info = ref->extents + sorted[i].slot;
 		ret = __btrfs_free_extent(trans, root, info->bytenr,
 					  info->num_bytes, ref->bytenr,
 					  ref->owner, ref->generation,
@@ -3453,6 +3582,7 @@ static noinline int cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
 		info++;
 	}
 
+	kfree(sorted);
 	return 0;
 }
 
@@ -3497,6 +3627,152 @@ static int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start,
 }
 
 /*
+ * this is used while deleting old snapshots, and it drops the refs
+ * on a whole subtree starting from a level 1 node.
+ *
+ * The idea is to sort all the leaf pointers, and then drop the
+ * ref on all the leaves in order.  Most of the time the leaves
+ * will have ref cache entries, so no leaf IOs will be required to
+ * find the extents they have references on.
+ *
+ * For each leaf, any references it has are also dropped in order
+ *
+ * This ends up dropping the references in something close to optimal
+ * order for reading and modifying the extent allocation tree.
+ */
+static noinline int drop_level_one_refs(struct btrfs_trans_handle *trans,
+					struct btrfs_root *root,
+					struct btrfs_path *path)
+{
+	u64 bytenr;
+	u64 root_owner;
+	u64 root_gen;
+	struct extent_buffer *eb = path->nodes[1];
+	struct extent_buffer *leaf;
+	struct btrfs_leaf_ref *ref;
+	struct refsort *sorted = NULL;
+	int nritems = btrfs_header_nritems(eb);
+	int ret;
+	int i;
+	int refi = 0;
+	int slot = path->slots[1];
+	u32 blocksize = btrfs_level_size(root, 0);
+	u32 refs;
+
+	if (nritems == 0)
+		goto out;
+
+	root_owner = btrfs_header_owner(eb);
+	root_gen = btrfs_header_generation(eb);
+	sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS);
+
+	/*
+	 * step one, sort all the leaf pointers so we don't scribble
+	 * randomly into the extent allocation tree
+	 */
+	for (i = slot; i < nritems; i++) {
+		sorted[refi].bytenr = btrfs_node_blockptr(eb, i);
+		sorted[refi].slot = i;
+		refi++;
+	}
+
+	/*
+	 * nritems won't be zero, but if we're picking up drop_snapshot
+	 * after a crash, slot might be > 0, so double check things
+	 * just in case.
+	 */
+	if (refi == 0)
+		goto out;
+
+	sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL);
+
+	/*
+	 * the first loop frees everything the leaves point to
+	 */
+	for (i = 0; i < refi; i++) {
+		u64 ptr_gen;
+
+		bytenr = sorted[i].bytenr;
+
+		/*
+		 * check the reference count on this leaf.  If it is > 1
+		 * we just decrement it below and don't update any
+		 * of the refs the leaf points to.
+		 */
+		ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs);
+		BUG_ON(ret);
+		if (refs != 1)
+			continue;
+
+		ptr_gen = btrfs_node_ptr_generation(eb, sorted[i].slot);
+
+		/*
+		 * the leaf only had one reference, which means the
+		 * only thing pointing to this leaf is the snapshot
+		 * we're deleting.  It isn't possible for the reference
+		 * count to increase again later
+		 *
+		 * The reference cache is checked for the leaf,
+		 * and if found we'll be able to drop any refs held by
+		 * the leaf without needing to read it in.
+		 */
+		ref = btrfs_lookup_leaf_ref(root, bytenr);
+		if (ref && ref->generation != ptr_gen) {
+			btrfs_free_leaf_ref(root, ref);
+			ref = NULL;
+		}
+		if (ref) {
+			ret = cache_drop_leaf_ref(trans, root, ref);
+			BUG_ON(ret);
+			btrfs_remove_leaf_ref(root, ref);
+			btrfs_free_leaf_ref(root, ref);
+		} else {
+			/*
+			 * the leaf wasn't in the reference cache, so
+			 * we have to read it.
+			 */
+			leaf = read_tree_block(root, bytenr, blocksize,
+					       ptr_gen);
+			ret = btrfs_drop_leaf_ref(trans, root, leaf);
+			BUG_ON(ret);
+			free_extent_buffer(leaf);
+		}
+		atomic_inc(&root->fs_info->throttle_gen);
+		wake_up(&root->fs_info->transaction_throttle);
+		cond_resched();
+	}
+
+	/*
+	 * run through the loop again to free the refs on the leaves.
+	 * This is faster than doing it in the loop above because
+	 * the leaves are likely to be clustered together.  We end up
+	 * working in nice chunks on the extent allocation tree.
+	 */
+	for (i = 0; i < refi; i++) {
+		bytenr = sorted[i].bytenr;
+		ret = __btrfs_free_extent(trans, root, bytenr,
+					blocksize, eb->start,
+					root_owner, root_gen, 0, 1);
+		BUG_ON(ret);
+
+		atomic_inc(&root->fs_info->throttle_gen);
+		wake_up(&root->fs_info->transaction_throttle);
+		cond_resched();
+	}
+out:
+	kfree(sorted);
+
+	/*
+	 * update the path to show we've processed the entire level 1
+	 * node.  This will get saved into the root's drop_snapshot_progress
+	 * field so these drops are not repeated again if this transaction
+	 * commits.
+	 */
+	path->slots[1] = nritems;
+	return 0;
+}
+
+/*
  * helper function for drop_snapshot, this walks down the tree dropping ref
  * counts as it goes.
  */
@@ -3511,7 +3787,6 @@ static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
 	struct extent_buffer *next;
 	struct extent_buffer *cur;
 	struct extent_buffer *parent;
-	struct btrfs_leaf_ref *ref;
 	u32 blocksize;
 	int ret;
 	u32 refs;
@@ -3538,17 +3813,46 @@ static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
 		if (path->slots[*level] >=
 		    btrfs_header_nritems(cur))
 			break;
+
+		/* the new code goes down to level 1 and does all the
+		 * leaves pointed to that node in bulk.  So, this check
+		 * for level 0 will always be false.
+		 *
+		 * But, the disk format allows the drop_snapshot_progress
+		 * field in the root to leave things in a state where
+		 * a leaf will need cleaning up here.  If someone crashes
+		 * with the old code and then boots with the new code,
+		 * we might find a leaf here.
+		 */
 		if (*level == 0) {
 			ret = btrfs_drop_leaf_ref(trans, root, cur);
 			BUG_ON(ret);
 			break;
 		}
+
+		/*
+		 * once we get to level one, process the whole node
+		 * at once, including everything below it.
+		 */
+		if (*level == 1) {
+			ret = drop_level_one_refs(trans, root, path);
+			BUG_ON(ret);
+			break;
+		}
+
 		bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
 		ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
 		blocksize = btrfs_level_size(root, *level - 1);
 
 		ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs);
 		BUG_ON(ret);
+
+		/*
+		 * if there is more than one reference, we don't need
+		 * to read that node to drop any references it has.  We
+		 * just drop the ref we hold on that node and move on to the
+		 * next slot in this level.
+		 */
 		if (refs != 1) {
 			parent = path->nodes[*level];
 			root_owner = btrfs_header_owner(parent);
@@ -3567,46 +3871,12 @@ static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
 
 			continue;
 		}
+
 		/*
-		 * at this point, we have a single ref, and since the
-		 * only place referencing this extent is a dead root
-		 * the reference count should never go higher.
-		 * So, we don't need to check it again
+		 * we need to keep freeing things in the next level down.
+		 * read the block and loop around to process it
 		 */
-		if (*level == 1) {
-			ref = btrfs_lookup_leaf_ref(root, bytenr);
-			if (ref && ref->generation != ptr_gen) {
-				btrfs_free_leaf_ref(root, ref);
-				ref = NULL;
-			}
-			if (ref) {
-				ret = cache_drop_leaf_ref(trans, root, ref);
-				BUG_ON(ret);
-				btrfs_remove_leaf_ref(root, ref);
-				btrfs_free_leaf_ref(root, ref);
-				*level = 0;
-				break;
-			}
-		}
-		next = btrfs_find_tree_block(root, bytenr, blocksize);
-		if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
-			free_extent_buffer(next);
-
-			next = read_tree_block(root, bytenr, blocksize,
-					       ptr_gen);
-			cond_resched();
-#if 0
-			/*
-			 * this is a debugging check and can go away
-			 * the ref should never go all the way down to 1
-			 * at this point
-			 */
-			ret = lookup_extent_ref(NULL, root, bytenr, blocksize,
-						&refs);
-			BUG_ON(ret);
-			WARN_ON(refs != 1);
-#endif
-		}
+		next = read_tree_block(root, bytenr, blocksize, ptr_gen);
 		WARN_ON(*level <= 0);
 		if (path->nodes[*level-1])
 			free_extent_buffer(path->nodes[*level-1]);
@@ -3631,11 +3901,16 @@ out:
 	root_owner = btrfs_header_owner(parent);
 	root_gen = btrfs_header_generation(parent);
 
+	/*
+	 * cleanup and free the reference on the last node
+	 * we processed
+	 */
 	ret = __btrfs_free_extent(trans, root, bytenr, blocksize,
 				  parent->start, root_owner, root_gen,
 				  *level, 1);
 	free_extent_buffer(path->nodes[*level]);
 	path->nodes[*level] = NULL;
+
 	*level += 1;
 	BUG_ON(ret);
 
@@ -3687,6 +3962,7 @@ static noinline int walk_down_subtree(struct btrfs_trans_handle *trans,
 
 		next = read_tree_block(root, bytenr, blocksize, ptr_gen);
 		btrfs_tree_lock(next);
+		btrfs_set_lock_blocking(next);
 
 		ret = btrfs_lookup_extent_ref(trans, root, bytenr, blocksize,
 					      &refs);
@@ -3754,6 +4030,13 @@ static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
 		if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
 			struct extent_buffer *node;
 			struct btrfs_disk_key disk_key;
+
+			/*
+			 * there is more work to do in this level.
+			 * Update the drop_progress marker to reflect
+			 * the work we've done so far, and then bump
+			 * the slot number
+			 */
 			node = path->nodes[i];
 			path->slots[i]++;
 			*level = i;
@@ -3765,6 +4048,11 @@ static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
 			return 0;
 		} else {
 			struct extent_buffer *parent;
+
+			/*
+			 * this whole node is done, free our reference
+			 * on it and go up one level
+			 */
 			if (path->nodes[*level] == root->node)
 				parent = path->nodes[*level];
 			else
@@ -4444,7 +4732,7 @@ static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
 	u64 lock_end = 0;
 	u64 num_bytes;
 	u64 ext_offset;
-	u64 first_pos;
+	u64 search_end = (u64)-1;
 	u32 nritems;
 	int nr_scaned = 0;
 	int extent_locked = 0;
@@ -4452,7 +4740,6 @@ static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
 	int ret;
 
 	memcpy(&key, leaf_key, sizeof(key));
-	first_pos = INT_LIMIT(loff_t) - extent_key->offset;
 	if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
 		if (key.objectid < ref_path->owner_objectid ||
 		    (key.objectid == ref_path->owner_objectid &&
@@ -4501,7 +4788,7 @@ next:
 			if ((key.objectid > ref_path->owner_objectid) ||
 			    (key.objectid == ref_path->owner_objectid &&
 			     key.type > BTRFS_EXTENT_DATA_KEY) ||
-			    (key.offset >= first_pos + extent_key->offset))
+			    key.offset >= search_end)
 				break;
 		}
 
@@ -4534,8 +4821,10 @@ next:
 		num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
 		ext_offset = btrfs_file_extent_offset(leaf, fi);
 
-		if (first_pos > key.offset - ext_offset)
-			first_pos = key.offset - ext_offset;
+		if (search_end == (u64)-1) {
+			search_end = key.offset - ext_offset +
+				btrfs_file_extent_ram_bytes(leaf, fi);
+		}
 
 		if (!extent_locked) {
 			lock_start = key.offset;
@@ -4724,7 +5013,7 @@ next:
 		}
 skip:
 		if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
-		    key.offset >= first_pos + extent_key->offset)
+		    key.offset >= search_end)
 			break;
 
 		cond_resched();
@@ -4778,6 +5067,7 @@ int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
 		ref->bytenr = buf->start;
 		ref->owner = btrfs_header_owner(buf);
 		ref->generation = btrfs_header_generation(buf);
+
 		ret = btrfs_add_leaf_ref(root, ref, 0);
 		WARN_ON(ret);
 		btrfs_free_leaf_ref(root, ref);
@@ -5957,9 +6247,11 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	path = btrfs_alloc_path();
 	BUG_ON(!path);
 
-	btrfs_remove_free_space_cache(block_group);
+	spin_lock(&root->fs_info->block_group_cache_lock);
 	rb_erase(&block_group->cache_node,
 		 &root->fs_info->block_group_cache_tree);
+	spin_unlock(&root->fs_info->block_group_cache_lock);
+	btrfs_remove_free_space_cache(block_group);
 	down_write(&block_group->space_info->groups_sem);
 	list_del(&block_group->list);
 	up_write(&block_group->space_info->groups_sem);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index e086d407f1f..37d43b516b7 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -9,7 +9,6 @@
 #include <linux/spinlock.h>
 #include <linux/blkdev.h>
 #include <linux/swap.h>
-#include <linux/version.h>
 #include <linux/writeback.h>
 #include <linux/pagevec.h>
 #include "extent_io.h"
@@ -31,7 +30,7 @@ static LIST_HEAD(buffers);
 static LIST_HEAD(states);
 
 #define LEAK_DEBUG 0
-#ifdef LEAK_DEBUG
+#if LEAK_DEBUG
 static DEFINE_SPINLOCK(leak_lock);
 #endif
 
@@ -120,7 +119,7 @@ void extent_io_tree_init(struct extent_io_tree *tree,
 static struct extent_state *alloc_extent_state(gfp_t mask)
 {
 	struct extent_state *state;
-#ifdef LEAK_DEBUG
+#if LEAK_DEBUG
 	unsigned long flags;
 #endif
 
@@ -130,7 +129,7 @@ static struct extent_state *alloc_extent_state(gfp_t mask)
 	state->state = 0;
 	state->private = 0;
 	state->tree = NULL;
-#ifdef LEAK_DEBUG
+#if LEAK_DEBUG
 	spin_lock_irqsave(&leak_lock, flags);
 	list_add(&state->leak_list, &states);
 	spin_unlock_irqrestore(&leak_lock, flags);
@@ -145,11 +144,11 @@ static void free_extent_state(struct extent_state *state)
 	if (!state)
 		return;
 	if (atomic_dec_and_test(&state->refs)) {
-#ifdef LEAK_DEBUG
+#if LEAK_DEBUG
 		unsigned long flags;
 #endif
 		WARN_ON(state->tree);
-#ifdef LEAK_DEBUG
+#if LEAK_DEBUG
 		spin_lock_irqsave(&leak_lock, flags);
 		list_del(&state->leak_list);
 		spin_unlock_irqrestore(&leak_lock, flags);
@@ -2378,11 +2377,6 @@ static int extent_write_cache_pages(struct extent_io_tree *tree,
 	int scanned = 0;
 	int range_whole = 0;
 
-	if (wbc->nonblocking && bdi_write_congested(bdi)) {
-		wbc->encountered_congestion = 1;
-		return 0;
-	}
-
 	pagevec_init(&pvec, 0);
 	if (wbc->range_cyclic) {
 		index = mapping->writeback_index; /* Start from prev offset */
@@ -2855,6 +2849,98 @@ out:
 	return sector;
 }
 
+int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+		__u64 start, __u64 len, get_extent_t *get_extent)
+{
+	int ret;
+	u64 off = start;
+	u64 max = start + len;
+	u32 flags = 0;
+	u64 disko = 0;
+	struct extent_map *em = NULL;
+	int end = 0;
+	u64 em_start = 0, em_len = 0;
+	unsigned long emflags;
+	ret = 0;
+
+	if (len == 0)
+		return -EINVAL;
+
+	lock_extent(&BTRFS_I(inode)->io_tree, start, start + len,
+		GFP_NOFS);
+	em = get_extent(inode, NULL, 0, off, max - off, 0);
+	if (!em)
+		goto out;
+	if (IS_ERR(em)) {
+		ret = PTR_ERR(em);
+		goto out;
+	}
+	while (!end) {
+		off = em->start + em->len;
+		if (off >= max)
+			end = 1;
+
+		em_start = em->start;
+		em_len = em->len;
+
+		disko = 0;
+		flags = 0;
+
+		switch (em->block_start) {
+		case EXTENT_MAP_LAST_BYTE:
+			end = 1;
+			flags |= FIEMAP_EXTENT_LAST;
+			break;
+		case EXTENT_MAP_HOLE:
+			flags |= FIEMAP_EXTENT_UNWRITTEN;
+			break;
+		case EXTENT_MAP_INLINE:
+			flags |= (FIEMAP_EXTENT_DATA_INLINE |
+				  FIEMAP_EXTENT_NOT_ALIGNED);
+			break;
+		case EXTENT_MAP_DELALLOC:
+			flags |= (FIEMAP_EXTENT_DELALLOC |
+				  FIEMAP_EXTENT_UNKNOWN);
+			break;
+		default:
+			disko = em->block_start;
+			break;
+		}
+		if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
+			flags |= FIEMAP_EXTENT_ENCODED;
+
+		emflags = em->flags;
+		free_extent_map(em);
+		em = NULL;
+
+		if (!end) {
+			em = get_extent(inode, NULL, 0, off, max - off, 0);
+			if (!em)
+				goto out;
+			if (IS_ERR(em)) {
+				ret = PTR_ERR(em);
+				goto out;
+			}
+			emflags = em->flags;
+		}
+		if (test_bit(EXTENT_FLAG_VACANCY, &emflags)) {
+			flags |= FIEMAP_EXTENT_LAST;
+			end = 1;
+		}
+
+		ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
+					em_len, flags);
+		if (ret)
+			goto out_free;
+	}
+out_free:
+	free_extent_map(em);
+out:
+	unlock_extent(&BTRFS_I(inode)->io_tree, start, start + len,
+			GFP_NOFS);
+	return ret;
+}
+
 static inline struct page *extent_buffer_page(struct extent_buffer *eb,
 					      unsigned long i)
 {
@@ -2892,15 +2978,17 @@ static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
 						   gfp_t mask)
 {
 	struct extent_buffer *eb = NULL;
-#ifdef LEAK_DEBUG
+#if LEAK_DEBUG
 	unsigned long flags;
 #endif
 
 	eb = kmem_cache_zalloc(extent_buffer_cache, mask);
 	eb->start = start;
 	eb->len = len;
-	mutex_init(&eb->mutex);
-#ifdef LEAK_DEBUG
+	spin_lock_init(&eb->lock);
+	init_waitqueue_head(&eb->lock_wq);
+
+#if LEAK_DEBUG
 	spin_lock_irqsave(&leak_lock, flags);
 	list_add(&eb->leak_list, &buffers);
 	spin_unlock_irqrestore(&leak_lock, flags);
@@ -2912,7 +3000,7 @@ static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
 
 static void __free_extent_buffer(struct extent_buffer *eb)
 {
-#ifdef LEAK_DEBUG
+#if LEAK_DEBUG
 	unsigned long flags;
 	spin_lock_irqsave(&leak_lock, flags);
 	list_del(&eb->leak_list);
@@ -2980,8 +3068,7 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
 		unlock_page(p);
 	}
 	if (uptodate)
-		eb->flags |= EXTENT_UPTODATE;
-	eb->flags |= EXTENT_BUFFER_FILLED;
+		set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
 
 	spin_lock(&tree->buffer_lock);
 	exists = buffer_tree_insert(tree, start, &eb->rb_node);
@@ -3135,7 +3222,7 @@ int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
 	unsigned long num_pages;
 
 	num_pages = num_extent_pages(eb->start, eb->len);
-	eb->flags &= ~EXTENT_UPTODATE;
+	clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
 
 	clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
 			      GFP_NOFS);
@@ -3206,7 +3293,7 @@ int extent_buffer_uptodate(struct extent_io_tree *tree,
 	struct page *page;
 	int pg_uptodate = 1;
 
-	if (eb->flags & EXTENT_UPTODATE)
+	if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
 		return 1;
 
 	ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1,
@@ -3242,7 +3329,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 	struct bio *bio = NULL;
 	unsigned long bio_flags = 0;
 
-	if (eb->flags & EXTENT_UPTODATE)
+	if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
 		return 0;
 
 	if (test_range_bit(tree, eb->start, eb->start + eb->len - 1,
@@ -3273,7 +3360,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 	}
 	if (all_uptodate) {
 		if (start_i == 0)
-			eb->flags |= EXTENT_UPTODATE;
+			set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
 		goto unlock_exit;
 	}
 
@@ -3309,7 +3396,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 	}
 
 	if (!ret)
-		eb->flags |= EXTENT_UPTODATE;
+		set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
 	return ret;
 
 unlock_exit:
@@ -3406,7 +3493,6 @@ int map_extent_buffer(struct extent_buffer *eb, unsigned long start,
 		unmap_extent_buffer(eb, eb->map_token, km);
 		eb->map_token = NULL;
 		save = 1;
-		WARN_ON(!mutex_is_locked(&eb->mutex));
 	}
 	err = map_private_extent_buffer(eb, start, min_len, token, map,
 				       map_start, map_len, km);
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index c5b483a7913..1f9df88afbf 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -22,6 +22,10 @@
 /* flags for bio submission */
 #define EXTENT_BIO_COMPRESSED 1
 
+/* these are bit numbers for test/set bit */
+#define EXTENT_BUFFER_UPTODATE 0
+#define EXTENT_BUFFER_BLOCKING 1
+
 /*
  * page->private values.  Every page that is controlled by the extent
  * map has page->private set to one.
@@ -95,11 +99,19 @@ struct extent_buffer {
 	unsigned long map_start;
 	unsigned long map_len;
 	struct page *first_page;
+	unsigned long bflags;
 	atomic_t refs;
-	int flags;
 	struct list_head leak_list;
 	struct rb_node rb_node;
-	struct mutex mutex;
+
+	/* the spinlock is used to protect most operations */
+	spinlock_t lock;
+
+	/*
+	 * when we keep the lock held while blocking, waiters go onto
+	 * the wq
+	 */
+	wait_queue_head_t lock_wq;
 };
 
 struct extent_map_tree;
@@ -193,6 +205,8 @@ int extent_commit_write(struct extent_io_tree *tree,
 			unsigned from, unsigned to);
 sector_t extent_bmap(struct address_space *mapping, sector_t iblock,
 		get_extent_t *get_extent);
+int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+		__u64 start, __u64 len, get_extent_t *get_extent);
 int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end);
 int set_state_private(struct extent_io_tree *tree, u64 start, u64 private);
 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 4a83e33ada3..50da69da20c 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -3,7 +3,6 @@
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/spinlock.h>
-#include <linux/version.h>
 #include <linux/hardirq.h>
 #include "extent_map.h"
 
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 90268334145..3e8023efaff 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -29,7 +29,6 @@
 #include <linux/writeback.h>
 #include <linux/statfs.h>
 #include <linux/compat.h>
-#include <linux/version.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -1215,10 +1214,10 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync)
 	}
 	mutex_unlock(&root->fs_info->trans_mutex);
 
-	root->fs_info->tree_log_batch++;
+	root->log_batch++;
 	filemap_fdatawrite(inode->i_mapping);
 	btrfs_wait_ordered_range(inode, 0, (u64)-1);
-	root->fs_info->tree_log_batch++;
+	root->log_batch++;
 
 	/*
 	 * ok we haven't committed the transaction yet, lets do a commit
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 8adfe059ab4..8f0706210a4 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -34,7 +34,6 @@
 #include <linux/statfs.h>
 #include <linux/compat.h>
 #include <linux/bit_spinlock.h>
-#include <linux/version.h>
 #include <linux/xattr.h>
 #include <linux/posix_acl.h>
 #include <linux/falloc.h>
@@ -51,6 +50,7 @@
 #include "tree-log.h"
 #include "ref-cache.h"
 #include "compression.h"
+#include "locking.h"
 
 struct btrfs_iget_args {
 	u64 ino;
@@ -91,6 +91,16 @@ static noinline int cow_file_range(struct inode *inode,
 				   u64 start, u64 end, int *page_started,
 				   unsigned long *nr_written, int unlock);
 
+static int btrfs_init_inode_security(struct inode *inode,  struct inode *dir)
+{
+	int err;
+
+	err = btrfs_init_acl(inode, dir);
+	if (!err)
+		err = btrfs_xattr_security_init(inode, dir);
+	return err;
+}
+
 /*
  * a very lame attempt at stopping writes when the FS is 85% full.  There
  * are countless ways this is incorrect, but it is better than nothing.
@@ -350,6 +360,19 @@ again:
 	nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
 	nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
 
+	/*
+	 * we don't want to send crud past the end of i_size through
+	 * compression, that's just a waste of CPU time.  So, if the
+	 * end of the file is before the start of our current
+	 * requested range of bytes, we bail out to the uncompressed
+	 * cleanup code that can deal with all of this.
+	 *
+	 * It isn't really the fastest way to fix things, but this is a
+	 * very uncommon corner.
+	 */
+	if (actual_end <= start)
+		goto cleanup_and_bail_uncompressed;
+
 	total_compressed = actual_end - start;
 
 	/* we want to make sure that amount of ram required to uncompress
@@ -494,6 +517,7 @@ again:
 			goto again;
 		}
 	} else {
+cleanup_and_bail_uncompressed:
 		/*
 		 * No compression, but we still need to write the pages in
 		 * the file we've been given so far.  redirty the locked
@@ -1324,12 +1348,11 @@ static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
 			     struct inode *inode, u64 file_offset,
 			     struct list_head *list)
 {
-	struct list_head *cur;
 	struct btrfs_ordered_sum *sum;
 
 	btrfs_set_trans_block_group(trans, inode);
-	list_for_each(cur, list) {
-		sum = list_entry(cur, struct btrfs_ordered_sum, list);
+
+	list_for_each_entry(sum, list, list) {
 		btrfs_csum_file_blocks(trans,
 		       BTRFS_I(inode)->root->fs_info->csum_root, sum);
 	}
@@ -2013,6 +2036,7 @@ void btrfs_read_locked_inode(struct inode *inode)
 	BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
 
 	alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
+
 	BTRFS_I(inode)->block_group = btrfs_find_block_group(root, 0,
 						alloc_group_block, 0);
 	btrfs_free_path(path);
@@ -2039,6 +2063,7 @@ void btrfs_read_locked_inode(struct inode *inode)
 		inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
 		break;
 	default:
+		inode->i_op = &btrfs_special_inode_operations;
 		init_special_inode(inode, inode->i_mode, rdev);
 		break;
 	}
@@ -2108,6 +2133,7 @@ noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
 		goto failed;
 	}
 
+	btrfs_unlock_up_safe(path, 1);
 	leaf = path->nodes[0];
 	inode_item = btrfs_item_ptr(leaf, path->slots[0],
 				  struct btrfs_inode_item);
@@ -2429,6 +2455,8 @@ next_node:
 			ref->generation = leaf_gen;
 			ref->nritems = 0;
 
+			btrfs_sort_leaf_ref(ref);
+
 			ret = btrfs_add_leaf_ref(root, ref, 0);
 			WARN_ON(ret);
 			btrfs_free_leaf_ref(root, ref);
@@ -2476,7 +2504,7 @@ noinline int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
 	struct btrfs_path *path;
 	struct btrfs_key key;
 	struct btrfs_key found_key;
-	u32 found_type;
+	u32 found_type = (u8)-1;
 	struct extent_buffer *leaf;
 	struct btrfs_file_extent_item *fi;
 	u64 extent_start = 0;
@@ -2663,6 +2691,8 @@ next:
 			if (pending_del_nr)
 				goto del_pending;
 			btrfs_release_path(root, path);
+			if (found_type == BTRFS_INODE_ITEM_KEY)
+				break;
 			goto search_again;
 		}
 
@@ -2679,6 +2709,8 @@ del_pending:
 			BUG_ON(ret);
 			pending_del_nr = 0;
 			btrfs_release_path(root, path);
+			if (found_type == BTRFS_INODE_ITEM_KEY)
+				break;
 			goto search_again;
 		}
 	}
@@ -3265,7 +3297,7 @@ skip:
 
 	/* Reached end of directory/root. Bump pos past the last item. */
 	if (key_type == BTRFS_DIR_INDEX_KEY)
-		filp->f_pos = INT_LIMIT(typeof(filp->f_pos));
+		filp->f_pos = INT_LIMIT(off_t);
 	else
 		filp->f_pos++;
 nopos:
@@ -3458,7 +3490,14 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
 		root->highest_inode = objectid;
 
 	inode->i_uid = current_fsuid();
-	inode->i_gid = current_fsgid();
+
+	if (dir && (dir->i_mode & S_ISGID)) {
+		inode->i_gid = dir->i_gid;
+		if (S_ISDIR(mode))
+			mode |= S_ISGID;
+	} else
+		inode->i_gid = current_fsgid();
+
 	inode->i_mode = mode;
 	inode->i_ino = objectid;
 	inode_set_bytes(inode, 0);
@@ -3586,7 +3625,7 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
 	if (IS_ERR(inode))
 		goto out_unlock;
 
-	err = btrfs_init_acl(inode, dir);
+	err = btrfs_init_inode_security(inode, dir);
 	if (err) {
 		drop_inode = 1;
 		goto out_unlock;
@@ -3649,7 +3688,7 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
 	if (IS_ERR(inode))
 		goto out_unlock;
 
-	err = btrfs_init_acl(inode, dir);
+	err = btrfs_init_inode_security(inode, dir);
 	if (err) {
 		drop_inode = 1;
 		goto out_unlock;
@@ -3772,7 +3811,7 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 
 	drop_on_err = 1;
 
-	err = btrfs_init_acl(inode, dir);
+	err = btrfs_init_inode_security(inode, dir);
 	if (err)
 		goto out_fail;
 
@@ -4158,9 +4197,10 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
 	return -EINVAL;
 }
 
-static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
+static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+		__u64 start, __u64 len)
 {
-	return extent_bmap(mapping, iblock, btrfs_get_extent);
+	return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent);
 }
 
 int btrfs_readpage(struct file *file, struct page *page)
@@ -4733,7 +4773,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
 	if (IS_ERR(inode))
 		goto out_unlock;
 
-	err = btrfs_init_acl(inode, dir);
+	err = btrfs_init_inode_security(inode, dir);
 	if (err) {
 		drop_inode = 1;
 		goto out_unlock;
@@ -4987,13 +5027,24 @@ static struct extent_io_ops btrfs_extent_io_ops = {
 	.clear_bit_hook = btrfs_clear_bit_hook,
 };
 
+/*
+ * btrfs doesn't support the bmap operation because swapfiles
+ * use bmap to make a mapping of extents in the file.  They assume
+ * these extents won't change over the life of the file and they
+ * use the bmap result to do IO directly to the drive.
+ *
+ * the btrfs bmap call would return logical addresses that aren't
+ * suitable for IO and they also will change frequently as COW
+ * operations happen.  So, swapfile + btrfs == corruption.
+ *
+ * For now we're avoiding this by dropping bmap.
+ */
 static struct address_space_operations btrfs_aops = {
 	.readpage	= btrfs_readpage,
 	.writepage	= btrfs_writepage,
 	.writepages	= btrfs_writepages,
 	.readpages	= btrfs_readpages,
 	.sync_page	= block_sync_page,
-	.bmap		= btrfs_bmap,
 	.direct_IO	= btrfs_direct_IO,
 	.invalidatepage = btrfs_invalidatepage,
 	.releasepage	= btrfs_releasepage,
@@ -5017,6 +5068,7 @@ static struct inode_operations btrfs_file_inode_operations = {
 	.removexattr	= btrfs_removexattr,
 	.permission	= btrfs_permission,
 	.fallocate	= btrfs_fallocate,
+	.fiemap		= btrfs_fiemap,
 };
 static struct inode_operations btrfs_special_inode_operations = {
 	.getattr	= btrfs_getattr,
@@ -5032,4 +5084,8 @@ static struct inode_operations btrfs_symlink_inode_operations = {
 	.follow_link	= page_follow_link_light,
 	.put_link	= page_put_link,
 	.permission	= btrfs_permission,
+	.setxattr	= btrfs_setxattr,
+	.getxattr	= btrfs_getxattr,
+	.listxattr	= btrfs_listxattr,
+	.removexattr	= btrfs_removexattr,
 };
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index c2aa33e3feb..988fdc8b49e 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -38,7 +38,6 @@
 #include <linux/compat.h>
 #include <linux/bit_spinlock.h>
 #include <linux/security.h>
-#include <linux/version.h>
 #include <linux/xattr.h>
 #include <linux/vmalloc.h>
 #include "compat.h"
diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index 39bae7761db..68fd9ccf180 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -26,45 +26,215 @@
 #include "locking.h"
 
 /*
- * locks the per buffer mutex in an extent buffer.  This uses adaptive locks
- * and the spin is not tuned very extensively.  The spinning does make a big
- * difference in almost every workload, but spinning for the right amount of
- * time needs some help.
- *
- * In general, we want to spin as long as the lock holder is doing btree
- * searches, and we should give up if they are in more expensive code.
+ * btrfs_header_level() isn't free, so don't call it when lockdep isn't
+ * on
  */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static inline void spin_nested(struct extent_buffer *eb)
+{
+	spin_lock_nested(&eb->lock, BTRFS_MAX_LEVEL - btrfs_header_level(eb));
+}
+#else
+static inline void spin_nested(struct extent_buffer *eb)
+{
+	spin_lock(&eb->lock);
+}
+#endif
 
-int btrfs_tree_lock(struct extent_buffer *eb)
+/*
+ * Setting a lock to blocking will drop the spinlock and set the
+ * flag that forces other procs who want the lock to wait.  After
+ * this you can safely schedule with the lock held.
+ */
+void btrfs_set_lock_blocking(struct extent_buffer *eb)
 {
-	int i;
+	if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags)) {
+		set_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags);
+		spin_unlock(&eb->lock);
+	}
+	/* exit with the spin lock released and the bit set */
+}
 
-	if (mutex_trylock(&eb->mutex))
-		return 0;
+/*
+ * clearing the blocking flag will take the spinlock again.
+ * After this you can't safely schedule
+ */
+void btrfs_clear_lock_blocking(struct extent_buffer *eb)
+{
+	if (test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags)) {
+		spin_nested(eb);
+		clear_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags);
+		smp_mb__after_clear_bit();
+	}
+	/* exit with the spin lock held */
+}
+
+/*
+ * unfortunately, many of the places that currently set a lock to blocking
+ * don't end up blocking for every long, and often they don't block
+ * at all.  For a dbench 50 run, if we don't spin one the blocking bit
+ * at all, the context switch rate can jump up to 400,000/sec or more.
+ *
+ * So, we're still stuck with this crummy spin on the blocking bit,
+ * at least until the most common causes of the short blocks
+ * can be dealt with.
+ */
+static int btrfs_spin_on_block(struct extent_buffer *eb)
+{
+	int i;
 	for (i = 0; i < 512; i++) {
 		cpu_relax();
-		if (mutex_trylock(&eb->mutex))
+		if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
+			return 1;
+		if (need_resched())
+			break;
+	}
+	return 0;
+}
+
+/*
+ * This is somewhat different from trylock.  It will take the
+ * spinlock but if it finds the lock is set to blocking, it will
+ * return without the lock held.
+ *
+ * returns 1 if it was able to take the lock and zero otherwise
+ *
+ * After this call, scheduling is not safe without first calling
+ * btrfs_set_lock_blocking()
+ */
+int btrfs_try_spin_lock(struct extent_buffer *eb)
+{
+	int i;
+
+	spin_nested(eb);
+	if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
+		return 1;
+	spin_unlock(&eb->lock);
+
+	/* spin for a bit on the BLOCKING flag */
+	for (i = 0; i < 2; i++) {
+		if (!btrfs_spin_on_block(eb))
+			break;
+
+		spin_nested(eb);
+		if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
+			return 1;
+		spin_unlock(&eb->lock);
+	}
+	return 0;
+}
+
+/*
+ * the autoremove wake function will return 0 if it tried to wake up
+ * a process that was already awake, which means that process won't
+ * count as an exclusive wakeup.  The waitq code will continue waking
+ * procs until it finds one that was actually sleeping.
+ *
+ * For btrfs, this isn't quite what we want.  We want a single proc
+ * to be notified that the lock is ready for taking.  If that proc
+ * already happen to be awake, great, it will loop around and try for
+ * the lock.
+ *
+ * So, btrfs_wake_function always returns 1, even when the proc that we
+ * tried to wake up was already awake.
+ */
+static int btrfs_wake_function(wait_queue_t *wait, unsigned mode,
+			       int sync, void *key)
+{
+	autoremove_wake_function(wait, mode, sync, key);
+	return 1;
+}
+
+/*
+ * returns with the extent buffer spinlocked.
+ *
+ * This will spin and/or wait as required to take the lock, and then
+ * return with the spinlock held.
+ *
+ * After this call, scheduling is not safe without first calling
+ * btrfs_set_lock_blocking()
+ */
+int btrfs_tree_lock(struct extent_buffer *eb)
+{
+	DEFINE_WAIT(wait);
+	wait.func = btrfs_wake_function;
+
+	while(1) {
+		spin_nested(eb);
+
+		/* nobody is blocking, exit with the spinlock held */
+		if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
 			return 0;
+
+		/*
+		 * we have the spinlock, but the real owner is blocking.
+		 * wait for them
+		 */
+		spin_unlock(&eb->lock);
+
+		/*
+		 * spin for a bit, and if the blocking flag goes away,
+		 * loop around
+		 */
+		if (btrfs_spin_on_block(eb))
+			continue;
+
+		prepare_to_wait_exclusive(&eb->lock_wq, &wait,
+					  TASK_UNINTERRUPTIBLE);
+
+		if (test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
+			schedule();
+
+		finish_wait(&eb->lock_wq, &wait);
 	}
-	cpu_relax();
-	mutex_lock_nested(&eb->mutex, BTRFS_MAX_LEVEL - btrfs_header_level(eb));
 	return 0;
 }
 
+/*
+ * Very quick trylock, this does not spin or schedule.  It returns
+ * 1 with the spinlock held if it was able to take the lock, or it
+ * returns zero if it was unable to take the lock.
+ *
+ * After this call, scheduling is not safe without first calling
+ * btrfs_set_lock_blocking()
+ */
 int btrfs_try_tree_lock(struct extent_buffer *eb)
 {
-	return mutex_trylock(&eb->mutex);
+	if (spin_trylock(&eb->lock)) {
+		if (test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags)) {
+			/*
+			 * we've got the spinlock, but the real owner is
+			 * blocking.  Drop the spinlock and return failure
+			 */
+			spin_unlock(&eb->lock);
+			return 0;
+		}
+		return 1;
+	}
+	/* someone else has the spinlock giveup */
+	return 0;
 }
 
 int btrfs_tree_unlock(struct extent_buffer *eb)
 {
-	mutex_unlock(&eb->mutex);
+	/*
+	 * if we were a blocking owner, we don't have the spinlock held
+	 * just clear the bit and look for waiters
+	 */
+	if (test_and_clear_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
+		smp_mb__after_clear_bit();
+	else
+		spin_unlock(&eb->lock);
+
+	if (waitqueue_active(&eb->lock_wq))
+		wake_up(&eb->lock_wq);
 	return 0;
 }
 
 int btrfs_tree_locked(struct extent_buffer *eb)
 {
-	return mutex_is_locked(&eb->mutex);
+	return test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags) ||
+			spin_is_locked(&eb->lock);
 }
 
 /*
@@ -75,12 +245,14 @@ int btrfs_path_lock_waiting(struct btrfs_path *path, int level)
 {
 	int i;
 	struct extent_buffer *eb;
+
 	for (i = level; i <= level + 1 && i < BTRFS_MAX_LEVEL; i++) {
 		eb = path->nodes[i];
 		if (!eb)
 			break;
 		smp_mb();
-		if (!list_empty(&eb->mutex.wait_list))
+		if (spin_is_contended(&eb->lock) ||
+		    waitqueue_active(&eb->lock_wq))
 			return 1;
 	}
 	return 0;
diff --git a/fs/btrfs/locking.h b/fs/btrfs/locking.h
index bc1faef1251..d92e707f587 100644
--- a/fs/btrfs/locking.h
+++ b/fs/btrfs/locking.h
@@ -22,6 +22,12 @@
 int btrfs_tree_lock(struct extent_buffer *eb);
 int btrfs_tree_unlock(struct extent_buffer *eb);
 int btrfs_tree_locked(struct extent_buffer *eb);
+
 int btrfs_try_tree_lock(struct extent_buffer *eb);
+int btrfs_try_spin_lock(struct extent_buffer *eb);
+
 int btrfs_path_lock_waiting(struct btrfs_path *path, int level);
+
+void btrfs_set_lock_blocking(struct extent_buffer *eb);
+void btrfs_clear_lock_blocking(struct extent_buffer *eb);
 #endif
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index a2094017027..77c2411a5f0 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -613,7 +613,6 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
 	struct btrfs_sector_sum *sector_sums;
 	struct btrfs_ordered_extent *ordered;
 	struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
-	struct list_head *cur;
 	unsigned long num_sectors;
 	unsigned long i;
 	u32 sectorsize = BTRFS_I(inode)->root->sectorsize;
@@ -624,8 +623,7 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
 		return 1;
 
 	mutex_lock(&tree->mutex);
-	list_for_each_prev(cur, &ordered->list) {
-		ordered_sum = list_entry(cur, struct btrfs_ordered_sum, list);
+	list_for_each_entry_reverse(ordered_sum, &ordered->list, list) {
 		if (disk_bytenr >= ordered_sum->bytenr) {
 			num_sectors = ordered_sum->len / sectorsize;
 			sector_sums = ordered_sum->sums;
diff --git a/fs/btrfs/ref-cache.c b/fs/btrfs/ref-cache.c
index 6f0acc4c9ea..d0cc62bccb9 100644
--- a/fs/btrfs/ref-cache.c
+++ b/fs/btrfs/ref-cache.c
@@ -17,6 +17,7 @@
  */
 
 #include <linux/sched.h>
+#include <linux/sort.h>
 #include "ctree.h"
 #include "ref-cache.h"
 #include "transaction.h"
diff --git a/fs/btrfs/ref-cache.h b/fs/btrfs/ref-cache.h
index 16f3183d7c5..bc283ad2db7 100644
--- a/fs/btrfs/ref-cache.h
+++ b/fs/btrfs/ref-cache.h
@@ -73,5 +73,4 @@ int btrfs_add_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref,
 int btrfs_remove_leaf_refs(struct btrfs_root *root, u64 max_root_gen,
 			   int shared);
 int btrfs_remove_leaf_ref(struct btrfs_root *root, struct btrfs_leaf_ref *ref);
-
 #endif
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index db9fb3bc1e3..f3fd7e2cbc3 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -37,7 +37,6 @@
 #include <linux/ctype.h>
 #include <linux/namei.h>
 #include <linux/miscdevice.h>
-#include <linux/version.h>
 #include <linux/magic.h>
 #include "compat.h"
 #include "ctree.h"
@@ -583,17 +582,18 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
 	struct btrfs_ioctl_vol_args *vol;
 	struct btrfs_fs_devices *fs_devices;
 	int ret = -ENOTTY;
-	int len;
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
 	vol = kmalloc(sizeof(*vol), GFP_KERNEL);
+	if (!vol)
+		return -ENOMEM;
+
 	if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) {
 		ret = -EFAULT;
 		goto out;
 	}
-	len = strnlen(vol->name, BTRFS_PATH_NAME_MAX);
 
 	switch (cmd) {
 	case BTRFS_IOC_SCAN_DEV:
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 8a08f944334..919172de5c9 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -852,11 +852,9 @@ static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans,
 {
 	struct btrfs_pending_snapshot *pending;
 	struct list_head *head = &trans->transaction->pending_snapshots;
-	struct list_head *cur;
 	int ret;
 
-	list_for_each(cur, head) {
-		pending = list_entry(cur, struct btrfs_pending_snapshot, list);
+	list_for_each_entry(pending, head, list) {
 		ret = create_pending_snapshot(trans, fs_info, pending);
 		BUG_ON(ret);
 	}
diff --git a/fs/btrfs/tree-defrag.c b/fs/btrfs/tree-defrag.c
index 3e8358c3616..98d25fa4570 100644
--- a/fs/btrfs/tree-defrag.c
+++ b/fs/btrfs/tree-defrag.c
@@ -74,6 +74,7 @@ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
 		u32 nritems;
 
 		root_node = btrfs_lock_root_node(root);
+		btrfs_set_lock_blocking(root_node);
 		nritems = btrfs_header_nritems(root_node);
 		root->defrag_max.objectid = 0;
 		/* from above we know this is not a leaf */
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index d81cda2e077..20794290256 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -78,104 +78,6 @@ static int link_to_fixup_dir(struct btrfs_trans_handle *trans,
  */
 
 /*
- * btrfs_add_log_tree adds a new per-subvolume log tree into the
- * tree of log tree roots.  This must be called with a tree log transaction
- * running (see start_log_trans).
- */
-static int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
-		      struct btrfs_root *root)
-{
-	struct btrfs_key key;
-	struct btrfs_root_item root_item;
-	struct btrfs_inode_item *inode_item;
-	struct extent_buffer *leaf;
-	struct btrfs_root *new_root = root;
-	int ret;
-	u64 objectid = root->root_key.objectid;
-
-	leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
-				      BTRFS_TREE_LOG_OBJECTID,
-				      trans->transid, 0, 0, 0);
-	if (IS_ERR(leaf)) {
-		ret = PTR_ERR(leaf);
-		return ret;
-	}
-
-	btrfs_set_header_nritems(leaf, 0);
-	btrfs_set_header_level(leaf, 0);
-	btrfs_set_header_bytenr(leaf, leaf->start);
-	btrfs_set_header_generation(leaf, trans->transid);
-	btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
-
-	write_extent_buffer(leaf, root->fs_info->fsid,
-			    (unsigned long)btrfs_header_fsid(leaf),
-			    BTRFS_FSID_SIZE);
-	btrfs_mark_buffer_dirty(leaf);
-
-	inode_item = &root_item.inode;
-	memset(inode_item, 0, sizeof(*inode_item));
-	inode_item->generation = cpu_to_le64(1);
-	inode_item->size = cpu_to_le64(3);
-	inode_item->nlink = cpu_to_le32(1);
-	inode_item->nbytes = cpu_to_le64(root->leafsize);
-	inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
-
-	btrfs_set_root_bytenr(&root_item, leaf->start);
-	btrfs_set_root_generation(&root_item, trans->transid);
-	btrfs_set_root_level(&root_item, 0);
-	btrfs_set_root_refs(&root_item, 0);
-	btrfs_set_root_used(&root_item, 0);
-
-	memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
-	root_item.drop_level = 0;
-
-	btrfs_tree_unlock(leaf);
-	free_extent_buffer(leaf);
-	leaf = NULL;
-
-	btrfs_set_root_dirid(&root_item, 0);
-
-	key.objectid = BTRFS_TREE_LOG_OBJECTID;
-	key.offset = objectid;
-	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
-	ret = btrfs_insert_root(trans, root->fs_info->log_root_tree, &key,
-				&root_item);
-	if (ret)
-		goto fail;
-
-	new_root = btrfs_read_fs_root_no_radix(root->fs_info->log_root_tree,
-					       &key);
-	BUG_ON(!new_root);
-
-	WARN_ON(root->log_root);
-	root->log_root = new_root;
-
-	/*
-	 * log trees do not get reference counted because they go away
-	 * before a real commit is actually done.  They do store pointers
-	 * to file data extents, and those reference counts still get
-	 * updated (along with back refs to the log tree).
-	 */
-	new_root->ref_cows = 0;
-	new_root->last_trans = trans->transid;
-
-	/*
-	 * we need to make sure the root block for this new tree
-	 * is marked as dirty in the dirty_log_pages tree.  This
-	 * is how it gets flushed down to disk at tree log commit time.
-	 *
-	 * the tree logging mutex keeps others from coming in and changing
-	 * the new_root->node, so we can safely access it here
-	 */
-	set_extent_dirty(&new_root->dirty_log_pages, new_root->node->start,
-			 new_root->node->start + new_root->node->len - 1,
-			 GFP_NOFS);
-
-fail:
-	return ret;
-}
-
-/*
  * start a sub transaction and setup the log tree
  * this increments the log tree writer count to make the people
  * syncing the tree wait for us to finish
@@ -184,6 +86,14 @@ static int start_log_trans(struct btrfs_trans_handle *trans,
 			   struct btrfs_root *root)
 {
 	int ret;
+
+	mutex_lock(&root->log_mutex);
+	if (root->log_root) {
+		root->log_batch++;
+		atomic_inc(&root->log_writers);
+		mutex_unlock(&root->log_mutex);
+		return 0;
+	}
 	mutex_lock(&root->fs_info->tree_log_mutex);
 	if (!root->fs_info->log_root_tree) {
 		ret = btrfs_init_log_root_tree(trans, root->fs_info);
@@ -193,9 +103,10 @@ static int start_log_trans(struct btrfs_trans_handle *trans,
 		ret = btrfs_add_log_tree(trans, root);
 		BUG_ON(ret);
 	}
-	atomic_inc(&root->fs_info->tree_log_writers);
-	root->fs_info->tree_log_batch++;
 	mutex_unlock(&root->fs_info->tree_log_mutex);
+	root->log_batch++;
+	atomic_inc(&root->log_writers);
+	mutex_unlock(&root->log_mutex);
 	return 0;
 }
 
@@ -212,13 +123,12 @@ static int join_running_log_trans(struct btrfs_root *root)
 	if (!root->log_root)
 		return -ENOENT;
 
-	mutex_lock(&root->fs_info->tree_log_mutex);
+	mutex_lock(&root->log_mutex);
 	if (root->log_root) {
 		ret = 0;
-		atomic_inc(&root->fs_info->tree_log_writers);
-		root->fs_info->tree_log_batch++;
+		atomic_inc(&root->log_writers);
 	}
-	mutex_unlock(&root->fs_info->tree_log_mutex);
+	mutex_unlock(&root->log_mutex);
 	return ret;
 }
 
@@ -228,10 +138,11 @@ static int join_running_log_trans(struct btrfs_root *root)
  */
 static int end_log_trans(struct btrfs_root *root)
 {
-	atomic_dec(&root->fs_info->tree_log_writers);
-	smp_mb();
-	if (waitqueue_active(&root->fs_info->tree_log_wait))
-		wake_up(&root->fs_info->tree_log_wait);
+	if (atomic_dec_and_test(&root->log_writers)) {
+		smp_mb();
+		if (waitqueue_active(&root->log_writer_wait))
+			wake_up(&root->log_writer_wait);
+	}
 	return 0;
 }
 
@@ -1704,6 +1615,7 @@ static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
 
 				btrfs_tree_lock(next);
 				clean_tree_block(trans, root, next);
+				btrfs_set_lock_blocking(next);
 				btrfs_wait_tree_block_writeback(next);
 				btrfs_tree_unlock(next);
 
@@ -1750,6 +1662,7 @@ static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
 		next = path->nodes[*level];
 		btrfs_tree_lock(next);
 		clean_tree_block(trans, root, next);
+		btrfs_set_lock_blocking(next);
 		btrfs_wait_tree_block_writeback(next);
 		btrfs_tree_unlock(next);
 
@@ -1807,6 +1720,7 @@ static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans,
 
 				btrfs_tree_lock(next);
 				clean_tree_block(trans, root, next);
+				btrfs_set_lock_blocking(next);
 				btrfs_wait_tree_block_writeback(next);
 				btrfs_tree_unlock(next);
 
@@ -1879,6 +1793,7 @@ static int walk_log_tree(struct btrfs_trans_handle *trans,
 
 			btrfs_tree_lock(next);
 			clean_tree_block(trans, log, next);
+			btrfs_set_lock_blocking(next);
 			btrfs_wait_tree_block_writeback(next);
 			btrfs_tree_unlock(next);
 
@@ -1902,26 +1817,65 @@ static int walk_log_tree(struct btrfs_trans_handle *trans,
 		}
 	}
 	btrfs_free_path(path);
-	if (wc->free)
-		free_extent_buffer(log->node);
 	return ret;
 }
 
-static int wait_log_commit(struct btrfs_root *log)
+/*
+ * helper function to update the item for a given subvolumes log root
+ * in the tree of log roots
+ */
+static int update_log_root(struct btrfs_trans_handle *trans,
+			   struct btrfs_root *log)
+{
+	int ret;
+
+	if (log->log_transid == 1) {
+		/* insert root item on the first sync */
+		ret = btrfs_insert_root(trans, log->fs_info->log_root_tree,
+				&log->root_key, &log->root_item);
+	} else {
+		ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
+				&log->root_key, &log->root_item);
+	}
+	return ret;
+}
+
+static int wait_log_commit(struct btrfs_root *root, unsigned long transid)
 {
 	DEFINE_WAIT(wait);
-	u64 transid = log->fs_info->tree_log_transid;
+	int index = transid % 2;
 
+	/*
+	 * we only allow two pending log transactions at a time,
+	 * so we know that if ours is more than 2 older than the
+	 * current transaction, we're done
+	 */
 	do {
-		prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
-				TASK_UNINTERRUPTIBLE);
-		mutex_unlock(&log->fs_info->tree_log_mutex);
-		if (atomic_read(&log->fs_info->tree_log_commit))
+		prepare_to_wait(&root->log_commit_wait[index],
+				&wait, TASK_UNINTERRUPTIBLE);
+		mutex_unlock(&root->log_mutex);
+		if (root->log_transid < transid + 2 &&
+		    atomic_read(&root->log_commit[index]))
 			schedule();
-		finish_wait(&log->fs_info->tree_log_wait, &wait);
-		mutex_lock(&log->fs_info->tree_log_mutex);
-	} while (transid == log->fs_info->tree_log_transid &&
-		atomic_read(&log->fs_info->tree_log_commit));
+		finish_wait(&root->log_commit_wait[index], &wait);
+		mutex_lock(&root->log_mutex);
+	} while (root->log_transid < transid + 2 &&
+		 atomic_read(&root->log_commit[index]));
+	return 0;
+}
+
+static int wait_for_writer(struct btrfs_root *root)
+{
+	DEFINE_WAIT(wait);
+	while (atomic_read(&root->log_writers)) {
+		prepare_to_wait(&root->log_writer_wait,
+				&wait, TASK_UNINTERRUPTIBLE);
+		mutex_unlock(&root->log_mutex);
+		if (atomic_read(&root->log_writers))
+			schedule();
+		mutex_lock(&root->log_mutex);
+		finish_wait(&root->log_writer_wait, &wait);
+	}
 	return 0;
 }
 
@@ -1933,57 +1887,114 @@ static int wait_log_commit(struct btrfs_root *log)
 int btrfs_sync_log(struct btrfs_trans_handle *trans,
 		   struct btrfs_root *root)
 {
+	int index1;
+	int index2;
 	int ret;
-	unsigned long batch;
 	struct btrfs_root *log = root->log_root;
+	struct btrfs_root *log_root_tree = root->fs_info->log_root_tree;
 
-	mutex_lock(&log->fs_info->tree_log_mutex);
-	if (atomic_read(&log->fs_info->tree_log_commit)) {
-		wait_log_commit(log);
-		goto out;
+	mutex_lock(&root->log_mutex);
+	index1 = root->log_transid % 2;
+	if (atomic_read(&root->log_commit[index1])) {
+		wait_log_commit(root, root->log_transid);
+		mutex_unlock(&root->log_mutex);
+		return 0;
 	}
-	atomic_set(&log->fs_info->tree_log_commit, 1);
+	atomic_set(&root->log_commit[index1], 1);
+
+	/* wait for previous tree log sync to complete */
+	if (atomic_read(&root->log_commit[(index1 + 1) % 2]))
+		wait_log_commit(root, root->log_transid - 1);
 
 	while (1) {
-		batch = log->fs_info->tree_log_batch;
-		mutex_unlock(&log->fs_info->tree_log_mutex);
+		unsigned long batch = root->log_batch;
+		mutex_unlock(&root->log_mutex);
 		schedule_timeout_uninterruptible(1);
-		mutex_lock(&log->fs_info->tree_log_mutex);
-
-		while (atomic_read(&log->fs_info->tree_log_writers)) {
-			DEFINE_WAIT(wait);
-			prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
-					TASK_UNINTERRUPTIBLE);
-			mutex_unlock(&log->fs_info->tree_log_mutex);
-			if (atomic_read(&log->fs_info->tree_log_writers))
-				schedule();
-			mutex_lock(&log->fs_info->tree_log_mutex);
-			finish_wait(&log->fs_info->tree_log_wait, &wait);
-		}
-		if (batch == log->fs_info->tree_log_batch)
+		mutex_lock(&root->log_mutex);
+		wait_for_writer(root);
+		if (batch == root->log_batch)
 			break;
 	}
 
 	ret = btrfs_write_and_wait_marked_extents(log, &log->dirty_log_pages);
 	BUG_ON(ret);
-	ret = btrfs_write_and_wait_marked_extents(root->fs_info->log_root_tree,
-			       &root->fs_info->log_root_tree->dirty_log_pages);
+
+	btrfs_set_root_bytenr(&log->root_item, log->node->start);
+	btrfs_set_root_generation(&log->root_item, trans->transid);
+	btrfs_set_root_level(&log->root_item, btrfs_header_level(log->node));
+
+	root->log_batch = 0;
+	root->log_transid++;
+	log->log_transid = root->log_transid;
+	smp_mb();
+	/*
+	 * log tree has been flushed to disk, new modifications of
+	 * the log will be written to new positions. so it's safe to
+	 * allow log writers to go in.
+	 */
+	mutex_unlock(&root->log_mutex);
+
+	mutex_lock(&log_root_tree->log_mutex);
+	log_root_tree->log_batch++;
+	atomic_inc(&log_root_tree->log_writers);
+	mutex_unlock(&log_root_tree->log_mutex);
+
+	ret = update_log_root(trans, log);
+	BUG_ON(ret);
+
+	mutex_lock(&log_root_tree->log_mutex);
+	if (atomic_dec_and_test(&log_root_tree->log_writers)) {
+		smp_mb();
+		if (waitqueue_active(&log_root_tree->log_writer_wait))
+			wake_up(&log_root_tree->log_writer_wait);
+	}
+
+	index2 = log_root_tree->log_transid % 2;
+	if (atomic_read(&log_root_tree->log_commit[index2])) {
+		wait_log_commit(log_root_tree, log_root_tree->log_transid);
+		mutex_unlock(&log_root_tree->log_mutex);
+		goto out;
+	}
+	atomic_set(&log_root_tree->log_commit[index2], 1);
+
+	if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2]))
+		wait_log_commit(log_root_tree, log_root_tree->log_transid - 1);
+
+	wait_for_writer(log_root_tree);
+
+	ret = btrfs_write_and_wait_marked_extents(log_root_tree,
+				&log_root_tree->dirty_log_pages);
 	BUG_ON(ret);
 
 	btrfs_set_super_log_root(&root->fs_info->super_for_commit,
-				 log->fs_info->log_root_tree->node->start);
+				log_root_tree->node->start);
 	btrfs_set_super_log_root_level(&root->fs_info->super_for_commit,
-		       btrfs_header_level(log->fs_info->log_root_tree->node));
+				btrfs_header_level(log_root_tree->node));
+
+	log_root_tree->log_batch = 0;
+	log_root_tree->log_transid++;
+	smp_mb();
+
+	mutex_unlock(&log_root_tree->log_mutex);
+
+	/*
+	 * nobody else is going to jump in and write the the ctree
+	 * super here because the log_commit atomic below is protecting
+	 * us.  We must be called with a transaction handle pinning
+	 * the running transaction open, so a full commit can't hop
+	 * in and cause problems either.
+	 */
+	write_ctree_super(trans, root->fs_info->tree_root, 2);
 
-	write_ctree_super(trans, log->fs_info->tree_root, 2);
-	log->fs_info->tree_log_transid++;
-	log->fs_info->tree_log_batch = 0;
-	atomic_set(&log->fs_info->tree_log_commit, 0);
+	atomic_set(&log_root_tree->log_commit[index2], 0);
 	smp_mb();
-	if (waitqueue_active(&log->fs_info->tree_log_wait))
-		wake_up(&log->fs_info->tree_log_wait);
+	if (waitqueue_active(&log_root_tree->log_commit_wait[index2]))
+		wake_up(&log_root_tree->log_commit_wait[index2]);
 out:
-	mutex_unlock(&log->fs_info->tree_log_mutex);
+	atomic_set(&root->log_commit[index1], 0);
+	smp_mb();
+	if (waitqueue_active(&root->log_commit_wait[index1]))
+		wake_up(&root->log_commit_wait[index1]);
 	return 0;
 }
 
@@ -2019,38 +2030,18 @@ int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
 				   start, end, GFP_NOFS);
 	}
 
-	log = root->log_root;
-	ret = btrfs_del_root(trans, root->fs_info->log_root_tree,
-			     &log->root_key);
-	BUG_ON(ret);
+	if (log->log_transid > 0) {
+		ret = btrfs_del_root(trans, root->fs_info->log_root_tree,
+				     &log->root_key);
+		BUG_ON(ret);
+	}
 	root->log_root = NULL;
-	kfree(root->log_root);
+	free_extent_buffer(log->node);
+	kfree(log);
 	return 0;
 }
 
 /*
- * helper function to update the item for a given subvolumes log root
- * in the tree of log roots
- */
-static int update_log_root(struct btrfs_trans_handle *trans,
-			   struct btrfs_root *log)
-{
-	u64 bytenr = btrfs_root_bytenr(&log->root_item);
-	int ret;
-
-	if (log->node->start == bytenr)
-		return 0;
-
-	btrfs_set_root_bytenr(&log->root_item, log->node->start);
-	btrfs_set_root_generation(&log->root_item, trans->transid);
-	btrfs_set_root_level(&log->root_item, btrfs_header_level(log->node));
-	ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
-				&log->root_key, &log->root_item);
-	BUG_ON(ret);
-	return ret;
-}
-
-/*
  * If both a file and directory are logged, and unlinks or renames are
  * mixed in, we have a few interesting corners:
  *
@@ -2711,11 +2702,6 @@ next_slot:
 
 	btrfs_free_path(path);
 	btrfs_free_path(dst_path);
-
-	mutex_lock(&root->fs_info->tree_log_mutex);
-	ret = update_log_root(trans, log);
-	BUG_ON(ret);
-	mutex_unlock(&root->fs_info->tree_log_mutex);
 out:
 	return 0;
 }
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 3451e1cca2b..bcd14ebccae 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -20,7 +20,6 @@
 #include <linux/buffer_head.h>
 #include <linux/blkdev.h>
 #include <linux/random.h>
-#include <linux/version.h>
 #include <asm/div64.h>
 #include "compat.h"
 #include "ctree.h"
@@ -104,10 +103,8 @@ static noinline struct btrfs_device *__find_device(struct list_head *head,
 						   u64 devid, u8 *uuid)
 {
 	struct btrfs_device *dev;
-	struct list_head *cur;
 
-	list_for_each(cur, head) {
-		dev = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(dev, head, dev_list) {
 		if (dev->devid == devid &&
 		    (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
 			return dev;
@@ -118,11 +115,9 @@ static noinline struct btrfs_device *__find_device(struct list_head *head,
 
 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
 {
-	struct list_head *cur;
 	struct btrfs_fs_devices *fs_devices;
 
-	list_for_each(cur, &fs_uuids) {
-		fs_devices = list_entry(cur, struct btrfs_fs_devices, list);
+	list_for_each_entry(fs_devices, &fs_uuids, list) {
 		if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
 			return fs_devices;
 	}
@@ -159,6 +154,7 @@ static noinline int run_scheduled_bios(struct btrfs_device *device)
 loop:
 	spin_lock(&device->io_lock);
 
+loop_lock:
 	/* take all the bios off the list at once and process them
 	 * later on (without the lock held).  But, remember the
 	 * tail and other pointers so the bios can be properly reinserted
@@ -208,7 +204,7 @@ loop:
 		 * is now congested.  Back off and let other work structs
 		 * run instead
 		 */
-		if (pending && bdi_write_congested(bdi) &&
+		if (pending && bdi_write_congested(bdi) && num_run > 16 &&
 		    fs_info->fs_devices->open_devices > 1) {
 			struct bio *old_head;
 
@@ -220,7 +216,8 @@ loop:
 				tail->bi_next = old_head;
 			else
 				device->pending_bio_tail = tail;
-			device->running_pending = 0;
+
+			device->running_pending = 1;
 
 			spin_unlock(&device->io_lock);
 			btrfs_requeue_work(&device->work);
@@ -229,6 +226,11 @@ loop:
 	}
 	if (again)
 		goto loop;
+
+	spin_lock(&device->io_lock);
+	if (device->pending_bios)
+		goto loop_lock;
+	spin_unlock(&device->io_lock);
 done:
 	return 0;
 }
@@ -345,14 +347,11 @@ error:
 
 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
 {
-	struct list_head *tmp;
-	struct list_head *cur;
-	struct btrfs_device *device;
+	struct btrfs_device *device, *next;
 
 	mutex_lock(&uuid_mutex);
 again:
-	list_for_each_safe(cur, tmp, &fs_devices->devices) {
-		device = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
 		if (device->in_fs_metadata)
 			continue;
 
@@ -383,14 +382,12 @@ again:
 
 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
 {
-	struct list_head *cur;
 	struct btrfs_device *device;
 
 	if (--fs_devices->opened > 0)
 		return 0;
 
-	list_for_each(cur, &fs_devices->devices) {
-		device = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(device, &fs_devices->devices, dev_list) {
 		if (device->bdev) {
 			close_bdev_exclusive(device->bdev, device->mode);
 			fs_devices->open_devices--;
@@ -439,7 +436,6 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 {
 	struct block_device *bdev;
 	struct list_head *head = &fs_devices->devices;
-	struct list_head *cur;
 	struct btrfs_device *device;
 	struct block_device *latest_bdev = NULL;
 	struct buffer_head *bh;
@@ -450,8 +446,7 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 	int seeding = 1;
 	int ret = 0;
 
-	list_for_each(cur, head) {
-		device = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(device, head, dev_list) {
 		if (device->bdev)
 			continue;
 		if (!device->name)
@@ -578,7 +573,7 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
 		       *(unsigned long long *)disk_super->fsid,
 		       *(unsigned long long *)(disk_super->fsid + 8));
 	}
-	printk(KERN_INFO "devid %llu transid %llu %s\n",
+	printk(KERN_CONT "devid %llu transid %llu %s\n",
 	       (unsigned long long)devid, (unsigned long long)transid, path);
 	ret = device_list_add(path, disk_super, devid, fs_devices_ret);
 
@@ -1017,14 +1012,12 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
 	}
 
 	if (strcmp(device_path, "missing") == 0) {
-		struct list_head *cur;
 		struct list_head *devices;
 		struct btrfs_device *tmp;
 
 		device = NULL;
 		devices = &root->fs_info->fs_devices->devices;
-		list_for_each(cur, devices) {
-			tmp = list_entry(cur, struct btrfs_device, dev_list);
+		list_for_each_entry(tmp, devices, dev_list) {
 			if (tmp->in_fs_metadata && !tmp->bdev) {
 				device = tmp;
 				break;
@@ -1280,7 +1273,6 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 	struct btrfs_trans_handle *trans;
 	struct btrfs_device *device;
 	struct block_device *bdev;
-	struct list_head *cur;
 	struct list_head *devices;
 	struct super_block *sb = root->fs_info->sb;
 	u64 total_bytes;
@@ -1304,8 +1296,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 	mutex_lock(&root->fs_info->volume_mutex);
 
 	devices = &root->fs_info->fs_devices->devices;
-	list_for_each(cur, devices) {
-		device = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(device, devices, dev_list) {
 		if (device->bdev == bdev) {
 			ret = -EEXIST;
 			goto error;
@@ -1704,7 +1695,6 @@ static u64 div_factor(u64 num, int factor)
 int btrfs_balance(struct btrfs_root *dev_root)
 {
 	int ret;
-	struct list_head *cur;
 	struct list_head *devices = &dev_root->fs_info->fs_devices->devices;
 	struct btrfs_device *device;
 	u64 old_size;
@@ -1723,8 +1713,7 @@ int btrfs_balance(struct btrfs_root *dev_root)
 	dev_root = dev_root->fs_info->dev_root;
 
 	/* step one make some room on all the devices */
-	list_for_each(cur, devices) {
-		device = list_entry(cur, struct btrfs_device, dev_list);
+	list_for_each_entry(device, devices, dev_list) {
 		old_size = device->total_bytes;
 		size_to_free = div_factor(old_size, 1);
 		size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index 7f332e27089..a9d3bf4d268 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -21,6 +21,7 @@
 #include <linux/slab.h>
 #include <linux/rwsem.h>
 #include <linux/xattr.h>
+#include <linux/security.h>
 #include "ctree.h"
 #include "btrfs_inode.h"
 #include "transaction.h"
@@ -45,9 +46,12 @@ ssize_t __btrfs_getxattr(struct inode *inode, const char *name,
 	/* lookup the xattr by name */
 	di = btrfs_lookup_xattr(NULL, root, path, inode->i_ino, name,
 				strlen(name), 0);
-	if (!di || IS_ERR(di)) {
+	if (!di) {
 		ret = -ENODATA;
 		goto out;
+	} else if (IS_ERR(di)) {
+		ret = PTR_ERR(di);
+		goto out;
 	}
 
 	leaf = path->nodes[0];
@@ -62,6 +66,14 @@ ssize_t __btrfs_getxattr(struct inode *inode, const char *name,
 		ret = -ERANGE;
 		goto out;
 	}
+
+	/*
+	 * The way things are packed into the leaf is like this
+	 * |struct btrfs_dir_item|name|data|
+	 * where name is the xattr name, so security.foo, and data is the
+	 * content of the xattr.  data_ptr points to the location in memory
+	 * where the data starts in the in memory leaf
+	 */
 	data_ptr = (unsigned long)((char *)(di + 1) +
 				   btrfs_dir_name_len(leaf, di));
 	read_extent_buffer(leaf, buffer, data_ptr,
@@ -86,7 +98,7 @@ int __btrfs_setxattr(struct inode *inode, const char *name,
 	if (!path)
 		return -ENOMEM;
 
-	trans = btrfs_start_transaction(root, 1);
+	trans = btrfs_join_transaction(root, 1);
 	btrfs_set_trans_block_group(trans, inode);
 
 	/* first lets see if we already have this xattr */
@@ -176,7 +188,6 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
 	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
 	if (ret < 0)
 		goto err;
-	ret = 0;
 	advance = 0;
 	while (1) {
 		leaf = path->nodes[0];
@@ -320,3 +331,34 @@ int btrfs_removexattr(struct dentry *dentry, const char *name)
 		return -EOPNOTSUPP;
 	return __btrfs_setxattr(dentry->d_inode, name, NULL, 0, XATTR_REPLACE);
 }
+
+int btrfs_xattr_security_init(struct inode *inode, struct inode *dir)
+{
+	int err;
+	size_t len;
+	void *value;
+	char *suffix;
+	char *name;
+
+	err = security_inode_init_security(inode, dir, &suffix, &value, &len);
+	if (err) {
+		if (err == -EOPNOTSUPP)
+			return 0;
+		return err;
+	}
+
+	name = kmalloc(XATTR_SECURITY_PREFIX_LEN + strlen(suffix) + 1,
+		       GFP_NOFS);
+	if (!name) {
+		err = -ENOMEM;
+	} else {
+		strcpy(name, XATTR_SECURITY_PREFIX);
+		strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix);
+		err = __btrfs_setxattr(inode, name, value, len, 0);
+		kfree(name);
+	}
+
+	kfree(suffix);
+	kfree(value);
+	return err;
+}
diff --git a/fs/btrfs/xattr.h b/fs/btrfs/xattr.h
index 5b1d08f8e68..c71e9c3cf3f 100644
--- a/fs/btrfs/xattr.h
+++ b/fs/btrfs/xattr.h
@@ -36,4 +36,6 @@ extern int btrfs_setxattr(struct dentry *dentry, const char *name,
 		const void *value, size_t size, int flags);
 extern int btrfs_removexattr(struct dentry *dentry, const char *name);
 
+extern int btrfs_xattr_security_init(struct inode *inode, struct inode *dir);
+
 #endif /* __XATTR__ */
diff --git a/fs/buffer.c b/fs/buffer.c
index b58208f1640..665d446b25b 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2688,7 +2688,7 @@ int nobh_write_end(struct file *file, struct address_space *mapping,
 	struct buffer_head *bh;
 	BUG_ON(fsdata != NULL && page_has_buffers(page));
 
-	if (unlikely(copied < len) && !page_has_buffers(page))
+	if (unlikely(copied < len) && head)
 		attach_nobh_buffers(page, head);
 	if (page_has_buffers(page))
 		return generic_write_end(file, mapping, pos, len,
diff --git a/fs/compat.c b/fs/compat.c
index 65a070e705a..d0145ca2757 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -1407,7 +1407,7 @@ int compat_do_execve(char * filename,
 	bprm->cred = prepare_exec_creds();
 	if (!bprm->cred)
 		goto out_unlock;
-	check_unsafe_exec(bprm);
+	check_unsafe_exec(bprm, current->files);
 
 	file = open_exec(filename);
 	retval = PTR_ERR(file);
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index c8f8d5904f5..9c6d815dd19 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -785,7 +785,7 @@ static int sg_ioctl_trans(unsigned int fd, unsigned int cmd, unsigned long arg)
 
 	if (copy_in_user(&sgio->status, &sgio32->status,
 			 (4 * sizeof(unsigned char)) +
-			 (2 * sizeof(unsigned (short))) +
+			 (2 * sizeof(unsigned short)) +
 			 (3 * sizeof(int))))
 		return -EFAULT;
 
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index c01e043670e..f6caeb1d110 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1716,7 +1716,7 @@ static int ecryptfs_copy_filename(char **copied_name, size_t *copied_name_size,
 {
 	int rc = 0;
 
-	(*copied_name) = kmalloc((name_size + 2), GFP_KERNEL);
+	(*copied_name) = kmalloc((name_size + 1), GFP_KERNEL);
 	if (!(*copied_name)) {
 		rc = -ENOMEM;
 		goto out;
@@ -1726,7 +1726,7 @@ static int ecryptfs_copy_filename(char **copied_name, size_t *copied_name_size,
 						 * in printing out the
 						 * string in debug
 						 * messages */
-	(*copied_name_size) = (name_size + 1);
+	(*copied_name_size) = name_size;
 out:
 	return rc;
 }
diff --git a/fs/exec.c b/fs/exec.c
index 0dd60a01f1b..929b58004b7 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1049,16 +1049,32 @@ EXPORT_SYMBOL(install_exec_creds);
  * - the caller must hold current->cred_exec_mutex to protect against
  *   PTRACE_ATTACH
  */
-void check_unsafe_exec(struct linux_binprm *bprm)
+void check_unsafe_exec(struct linux_binprm *bprm, struct files_struct *files)
 {
-	struct task_struct *p = current;
+	struct task_struct *p = current, *t;
+	unsigned long flags;
+	unsigned n_fs, n_files, n_sighand;
 
 	bprm->unsafe = tracehook_unsafe_exec(p);
 
-	if (atomic_read(&p->fs->count) > 1 ||
-	    atomic_read(&p->files->count) > 1 ||
-	    atomic_read(&p->sighand->count) > 1)
+	n_fs = 1;
+	n_files = 1;
+	n_sighand = 1;
+	lock_task_sighand(p, &flags);
+	for (t = next_thread(p); t != p; t = next_thread(t)) {
+		if (t->fs == p->fs)
+			n_fs++;
+		if (t->files == files)
+			n_files++;
+		n_sighand++;
+	}
+
+	if (atomic_read(&p->fs->count) > n_fs ||
+	    atomic_read(&p->files->count) > n_files ||
+	    atomic_read(&p->sighand->count) > n_sighand)
 		bprm->unsafe |= LSM_UNSAFE_SHARE;
+
+	unlock_task_sighand(p, &flags);
 }
 
 /* 
@@ -1273,7 +1289,7 @@ int do_execve(char * filename,
 	bprm->cred = prepare_exec_creds();
 	if (!bprm->cred)
 		goto out_unlock;
-	check_unsafe_exec(bprm);
+	check_unsafe_exec(bprm, displaced);
 
 	file = open_exec(filename);
 	retval = PTR_ERR(file);
diff --git a/fs/internal.h b/fs/internal.h
index 53af885f173..0d8ac497b3d 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -43,7 +43,7 @@ extern void __init chrdev_init(void);
 /*
  * exec.c
  */
-extern void check_unsafe_exec(struct linux_binprm *);
+extern void check_unsafe_exec(struct linux_binprm *, struct files_struct *);
 
 /*
  * namespace.c
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index d861096c9d8..60fe74035db 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -5390,6 +5390,9 @@ int ocfs2_remove_btree_range(struct inode *inode,
 		goto out;
 	}
 
+	vfs_dq_free_space_nodirty(inode,
+				  ocfs2_clusters_to_bytes(inode->i_sb, len));
+
 	ret = ocfs2_remove_extent(inode, et, cpos, len, handle, meta_ac,
 				  dealloc);
 	if (ret) {
diff --git a/fs/ocfs2/dcache.c b/fs/ocfs2/dcache.c
index b1cc7c381e8..e9d7c2038c0 100644
--- a/fs/ocfs2/dcache.c
+++ b/fs/ocfs2/dcache.c
@@ -38,6 +38,7 @@
 #include "dlmglue.h"
 #include "file.h"
 #include "inode.h"
+#include "super.h"
 
 
 static int ocfs2_dentry_revalidate(struct dentry *dentry,
@@ -294,6 +295,34 @@ out_attach:
 	return ret;
 }
 
+static DEFINE_SPINLOCK(dentry_list_lock);
+
+/* We limit the number of dentry locks to drop in one go. We have
+ * this limit so that we don't starve other users of ocfs2_wq. */
+#define DL_INODE_DROP_COUNT 64
+
+/* Drop inode references from dentry locks */
+void ocfs2_drop_dl_inodes(struct work_struct *work)
+{
+	struct ocfs2_super *osb = container_of(work, struct ocfs2_super,
+					       dentry_lock_work);
+	struct ocfs2_dentry_lock *dl;
+	int drop_count = DL_INODE_DROP_COUNT;
+
+	spin_lock(&dentry_list_lock);
+	while (osb->dentry_lock_list && drop_count--) {
+		dl = osb->dentry_lock_list;
+		osb->dentry_lock_list = dl->dl_next;
+		spin_unlock(&dentry_list_lock);
+		iput(dl->dl_inode);
+		kfree(dl);
+		spin_lock(&dentry_list_lock);
+	}
+	if (osb->dentry_lock_list)
+		queue_work(ocfs2_wq, &osb->dentry_lock_work);
+	spin_unlock(&dentry_list_lock);
+}
+
 /*
  * ocfs2_dentry_iput() and friends.
  *
@@ -318,16 +347,23 @@ out_attach:
 static void ocfs2_drop_dentry_lock(struct ocfs2_super *osb,
 				   struct ocfs2_dentry_lock *dl)
 {
-	iput(dl->dl_inode);
 	ocfs2_simple_drop_lockres(osb, &dl->dl_lockres);
 	ocfs2_lock_res_free(&dl->dl_lockres);
-	kfree(dl);
+
+	/* We leave dropping of inode reference to ocfs2_wq as that can
+	 * possibly lead to inode deletion which gets tricky */
+	spin_lock(&dentry_list_lock);
+	if (!osb->dentry_lock_list)
+		queue_work(ocfs2_wq, &osb->dentry_lock_work);
+	dl->dl_next = osb->dentry_lock_list;
+	osb->dentry_lock_list = dl;
+	spin_unlock(&dentry_list_lock);
 }
 
 void ocfs2_dentry_lock_put(struct ocfs2_super *osb,
 			   struct ocfs2_dentry_lock *dl)
 {
-	int unlock = 0;
+	int unlock;
 
 	BUG_ON(dl->dl_count == 0);
 
diff --git a/fs/ocfs2/dcache.h b/fs/ocfs2/dcache.h
index c091c34d988..d06e16c0664 100644
--- a/fs/ocfs2/dcache.h
+++ b/fs/ocfs2/dcache.h
@@ -29,8 +29,13 @@
 extern struct dentry_operations ocfs2_dentry_ops;
 
 struct ocfs2_dentry_lock {
+	/* Use count of dentry lock */
 	unsigned int		dl_count;
-	u64			dl_parent_blkno;
+	union {
+		/* Linked list of dentry locks to release */
+		struct ocfs2_dentry_lock *dl_next;
+		u64			dl_parent_blkno;
+	};
 
 	/*
 	 * The ocfs2_dentry_lock keeps an inode reference until
@@ -47,6 +52,8 @@ int ocfs2_dentry_attach_lock(struct dentry *dentry, struct inode *inode,
 void ocfs2_dentry_lock_put(struct ocfs2_super *osb,
 			   struct ocfs2_dentry_lock *dl);
 
+void ocfs2_drop_dl_inodes(struct work_struct *work);
+
 struct dentry *ocfs2_find_local_alias(struct inode *inode, u64 parent_blkno,
 				      int skip_unhashed);
 
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index b0c4cadd4c4..206a2370876 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -2860,6 +2860,10 @@ static void ocfs2_unlock_ast(void *opaque, int error)
 	case OCFS2_UNLOCK_CANCEL_CONVERT:
 		mlog(0, "Cancel convert success for %s\n", lockres->l_name);
 		lockres->l_action = OCFS2_AST_INVALID;
+		/* Downconvert thread may have requeued this lock, we
+		 * need to wake it. */
+		if (lockres->l_flags & OCFS2_LOCK_BLOCKED)
+			ocfs2_wake_downconvert_thread(ocfs2_get_lockres_osb(lockres));
 		break;
 	case OCFS2_UNLOCK_DROP_LOCK:
 		lockres->l_level = DLM_LOCK_IV;
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index ad5c24a29ed..077384135f4 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -210,6 +210,7 @@ struct ocfs2_journal;
 struct ocfs2_slot_info;
 struct ocfs2_recovery_map;
 struct ocfs2_quota_recovery;
+struct ocfs2_dentry_lock;
 struct ocfs2_super
 {
 	struct task_struct *commit_task;
@@ -325,6 +326,11 @@ struct ocfs2_super
 	struct list_head blocked_lock_list;
 	unsigned long blocked_lock_count;
 
+	/* List of dentry locks to release. Anyone can add locks to
+	 * the list, ocfs2_wq processes the list  */
+	struct ocfs2_dentry_lock *dentry_lock_list;
+	struct work_struct dentry_lock_work;
+
 	wait_queue_head_t		osb_mount_event;
 
 	/* Truncate log info */
diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
index f4efa89baee..1ed0f7c8686 100644
--- a/fs/ocfs2/quota_global.c
+++ b/fs/ocfs2/quota_global.c
@@ -754,7 +754,9 @@ static int ocfs2_mark_dquot_dirty(struct dquot *dquot)
 	if (dquot->dq_flags & mask)
 		sync = 1;
 	spin_unlock(&dq_data_lock);
-	if (!sync) {
+	/* This is a slight hack but we can't afford getting global quota
+	 * lock if we already have a transaction started. */
+	if (!sync || journal_current_handle()) {
 		status = ocfs2_write_dquot(dquot);
 		goto out;
 	}
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 43ed11345b5..b1cb38fbe80 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1887,6 +1887,9 @@ static int ocfs2_initialize_super(struct super_block *sb,
 	INIT_WORK(&journal->j_recovery_work, ocfs2_complete_recovery);
 	journal->j_state = OCFS2_JOURNAL_FREE;
 
+	INIT_WORK(&osb->dentry_lock_work, ocfs2_drop_dl_inodes);
+	osb->dentry_lock_list = NULL;
+
 	/* get some pseudo constants for clustersize bits */
 	osb->s_clustersize_bits =
 		le32_to_cpu(di->id2.i_super.s_clustersize_bits);
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index e1d638af6ac..915039fffe6 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -4729,13 +4729,6 @@ static int ocfs2_xattr_bucket_value_truncate(struct inode *inode,
 	vb.vb_xv = (struct ocfs2_xattr_value_root *)
 		(vb.vb_bh->b_data + offset % blocksize);
 
-	ret = ocfs2_xattr_bucket_journal_access(ctxt->handle, bucket,
-						OCFS2_JOURNAL_ACCESS_WRITE);
-	if (ret) {
-		mlog_errno(ret);
-		goto out;
-	}
-
 	/*
 	 * From here on out we have to dirty the bucket.  The generic
 	 * value calls only modify one of the bucket's bhs, but we need
@@ -4748,12 +4741,18 @@ static int ocfs2_xattr_bucket_value_truncate(struct inode *inode,
 	ret = ocfs2_xattr_value_truncate(inode, &vb, len, ctxt);
 	if (ret) {
 		mlog_errno(ret);
-		goto out_dirty;
+		goto out;
+	}
+
+	ret = ocfs2_xattr_bucket_journal_access(ctxt->handle, bucket,
+						OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
 	}
 
 	xe->xe_value_size = cpu_to_le64(len);
 
-out_dirty:
 	ocfs2_xattr_bucket_journal_dirty(ctxt->handle, bucket);
 
 out:
diff --git a/fs/seq_file.c b/fs/seq_file.c
index b569ff1c4dc..5267098532b 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -54,6 +54,64 @@ int seq_open(struct file *file, const struct seq_operations *op)
 }
 EXPORT_SYMBOL(seq_open);
 
+static int traverse(struct seq_file *m, loff_t offset)
+{
+	loff_t pos = 0, index;
+	int error = 0;
+	void *p;
+
+	m->version = 0;
+	index = 0;
+	m->count = m->from = 0;
+	if (!offset) {
+		m->index = index;
+		return 0;
+	}
+	if (!m->buf) {
+		m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL);
+		if (!m->buf)
+			return -ENOMEM;
+	}
+	p = m->op->start(m, &index);
+	while (p) {
+		error = PTR_ERR(p);
+		if (IS_ERR(p))
+			break;
+		error = m->op->show(m, p);
+		if (error < 0)
+			break;
+		if (unlikely(error)) {
+			error = 0;
+			m->count = 0;
+		}
+		if (m->count == m->size)
+			goto Eoverflow;
+		if (pos + m->count > offset) {
+			m->from = offset - pos;
+			m->count -= m->from;
+			m->index = index;
+			break;
+		}
+		pos += m->count;
+		m->count = 0;
+		if (pos == offset) {
+			index++;
+			m->index = index;
+			break;
+		}
+		p = m->op->next(m, p, &index);
+	}
+	m->op->stop(m, p);
+	m->index = index;
+	return error;
+
+Eoverflow:
+	m->op->stop(m, p);
+	kfree(m->buf);
+	m->buf = kmalloc(m->size <<= 1, GFP_KERNEL);
+	return !m->buf ? -ENOMEM : -EAGAIN;
+}
+
 /**
  *	seq_read -	->read() method for sequential files.
  *	@file: the file to read from
@@ -186,63 +244,6 @@ Efault:
 }
 EXPORT_SYMBOL(seq_read);
 
-static int traverse(struct seq_file *m, loff_t offset)
-{
-	loff_t pos = 0, index;
-	int error = 0;
-	void *p;
-
-	m->version = 0;
-	index = 0;
-	m->count = m->from = 0;
-	if (!offset) {
-		m->index = index;
-		return 0;
-	}
-	if (!m->buf) {
-		m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL);
-		if (!m->buf)
-			return -ENOMEM;
-	}
-	p = m->op->start(m, &index);
-	while (p) {
-		error = PTR_ERR(p);
-		if (IS_ERR(p))
-			break;
-		error = m->op->show(m, p);
-		if (error < 0)
-			break;
-		if (unlikely(error)) {
-			error = 0;
-			m->count = 0;
-		}
-		if (m->count == m->size)
-			goto Eoverflow;
-		if (pos + m->count > offset) {
-			m->from = offset - pos;
-			m->count -= m->from;
-			m->index = index;
-			break;
-		}
-		pos += m->count;
-		m->count = 0;
-		if (pos == offset) {
-			index++;
-			m->index = index;
-			break;
-		}
-		p = m->op->next(m, p, &index);
-	}
-	m->op->stop(m, p);
-	return error;
-
-Eoverflow:
-	m->op->stop(m, p);
-	kfree(m->buf);
-	m->buf = kmalloc(m->size <<= 1, GFP_KERNEL);
-	return !m->buf ? -ENOMEM : -EAGAIN;
-}
-
 /**
  *	seq_lseek -	->llseek() method for sequential files.
  *	@file: the file in question
diff --git a/fs/super.c b/fs/super.c
index 645e5403f2a..61dce001dd5 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -301,7 +301,7 @@ void generic_shutdown_super(struct super_block *sb)
 		/*
 		 * wait for asynchronous fs operations to finish before going further
 		 */
-		async_synchronize_full_special(&sb->s_async_list);
+		async_synchronize_full_domain(&sb->s_async_list);
 
 		/* bad name - it should be evict_inodes() */
 		invalidate_inodes(sb);
@@ -470,7 +470,7 @@ restart:
 		sb->s_count++;
 		spin_unlock(&sb_lock);
 		down_read(&sb->s_umount);
-		async_synchronize_full_special(&sb->s_async_list);
+		async_synchronize_full_domain(&sb->s_async_list);
 		if (sb->s_root && (wait || sb->s_dirt))
 			sb->s_op->sync_fs(sb, wait);
 		up_read(&sb->s_umount);
diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c
index 175f9c590b7..f393620890e 100644
--- a/fs/ubifs/budget.c
+++ b/fs/ubifs/budget.c
@@ -689,7 +689,7 @@ long long ubifs_reported_space(const struct ubifs_info *c, long long free)
 }
 
 /**
- * ubifs_get_free_space - return amount of free space.
+ * ubifs_get_free_space_nolock - return amount of free space.
  * @c: UBIFS file-system description object
  *
  * This function calculates amount of free space to report to user-space.
@@ -704,16 +704,14 @@ long long ubifs_reported_space(const struct ubifs_info *c, long long free)
  * traditional file-systems, because they have way less overhead than UBIFS.
  * So, to keep users happy, UBIFS tries to take the overhead into account.
  */
-long long ubifs_get_free_space(struct ubifs_info *c)
+long long ubifs_get_free_space_nolock(struct ubifs_info *c)
 {
-	int min_idx_lebs, rsvd_idx_lebs, lebs;
+	int rsvd_idx_lebs, lebs;
 	long long available, outstanding, free;
 
-	spin_lock(&c->space_lock);
-	min_idx_lebs = c->min_idx_lebs;
-	ubifs_assert(min_idx_lebs == ubifs_calc_min_idx_lebs(c));
+	ubifs_assert(c->min_idx_lebs == ubifs_calc_min_idx_lebs(c));
 	outstanding = c->budg_data_growth + c->budg_dd_growth;
-	available = ubifs_calc_available(c, min_idx_lebs);
+	available = ubifs_calc_available(c, c->min_idx_lebs);
 
 	/*
 	 * When reporting free space to user-space, UBIFS guarantees that it is
@@ -726,15 +724,14 @@ long long ubifs_get_free_space(struct ubifs_info *c)
 	 * Note, the calculations below are similar to what we have in
 	 * 'do_budget_space()', so refer there for comments.
 	 */
-	if (min_idx_lebs > c->lst.idx_lebs)
-		rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs;
+	if (c->min_idx_lebs > c->lst.idx_lebs)
+		rsvd_idx_lebs = c->min_idx_lebs - c->lst.idx_lebs;
 	else
 		rsvd_idx_lebs = 0;
 	lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
 	       c->lst.taken_empty_lebs;
 	lebs -= rsvd_idx_lebs;
 	available += lebs * (c->dark_wm - c->leb_overhead);
-	spin_unlock(&c->space_lock);
 
 	if (available > outstanding)
 		free = ubifs_reported_space(c, available - outstanding);
@@ -742,3 +739,21 @@ long long ubifs_get_free_space(struct ubifs_info *c)
 		free = 0;
 	return free;
 }
+
+/**
+ * ubifs_get_free_space - return amount of free space.
+ * @c: UBIFS file-system description object
+ *
+ * This function calculates and retuns amount of free space to report to
+ * user-space.
+ */
+long long ubifs_get_free_space(struct ubifs_info *c)
+{
+	long long free;
+
+	spin_lock(&c->space_lock);
+	free = ubifs_get_free_space_nolock(c);
+	spin_unlock(&c->space_lock);
+
+	return free;
+}
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 792c5a16c18..e975bd82f38 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -620,9 +620,11 @@ void dbg_dump_budg(struct ubifs_info *c)
 	       c->dark_wm, c->dead_wm, c->max_idx_node_sz);
 	printk(KERN_DEBUG "\tgc_lnum %d, ihead_lnum %d\n",
 	       c->gc_lnum, c->ihead_lnum);
-	for (i = 0; i < c->jhead_cnt; i++)
-		printk(KERN_DEBUG "\tjhead %d\t LEB %d\n",
-		       c->jheads[i].wbuf.jhead, c->jheads[i].wbuf.lnum);
+	/* If we are in R/O mode, journal heads do not exist */
+	if (c->jheads)
+		for (i = 0; i < c->jhead_cnt; i++)
+			printk(KERN_DEBUG "\tjhead %d\t LEB %d\n",
+			       c->jheads[i].wbuf.jhead, c->jheads[i].wbuf.lnum);
 	for (rb = rb_first(&c->buds); rb; rb = rb_next(rb)) {
 		bud = rb_entry(rb, struct ubifs_bud, rb);
 		printk(KERN_DEBUG "\tbud LEB %d\n", bud->lnum);
@@ -637,10 +639,7 @@ void dbg_dump_budg(struct ubifs_info *c)
 	/* Print budgeting predictions */
 	available = ubifs_calc_available(c, c->min_idx_lebs);
 	outstanding = c->budg_data_growth + c->budg_dd_growth;
-	if (available > outstanding)
-		free = ubifs_reported_space(c, available - outstanding);
-	else
-		free = 0;
+	free = ubifs_get_free_space_nolock(c);
 	printk(KERN_DEBUG "Budgeting predictions:\n");
 	printk(KERN_DEBUG "\tavailable: %lld, outstanding %lld, free %lld\n",
 	       available, outstanding, free);
@@ -861,6 +860,65 @@ void dbg_dump_index(struct ubifs_info *c)
 }
 
 /**
+ * dbg_save_space_info - save information about flash space.
+ * @c: UBIFS file-system description object
+ *
+ * This function saves information about UBIFS free space, dirty space, etc, in
+ * order to check it later.
+ */
+void dbg_save_space_info(struct ubifs_info *c)
+{
+	struct ubifs_debug_info *d = c->dbg;
+
+	ubifs_get_lp_stats(c, &d->saved_lst);
+
+	spin_lock(&c->space_lock);
+	d->saved_free = ubifs_get_free_space_nolock(c);
+	spin_unlock(&c->space_lock);
+}
+
+/**
+ * dbg_check_space_info - check flash space information.
+ * @c: UBIFS file-system description object
+ *
+ * This function compares current flash space information with the information
+ * which was saved when the 'dbg_save_space_info()' function was called.
+ * Returns zero if the information has not changed, and %-EINVAL it it has
+ * changed.
+ */
+int dbg_check_space_info(struct ubifs_info *c)
+{
+	struct ubifs_debug_info *d = c->dbg;
+	struct ubifs_lp_stats lst;
+	long long avail, free;
+
+	spin_lock(&c->space_lock);
+	avail = ubifs_calc_available(c, c->min_idx_lebs);
+	spin_unlock(&c->space_lock);
+	free = ubifs_get_free_space(c);
+
+	if (free != d->saved_free) {
+		ubifs_err("free space changed from %lld to %lld",
+			  d->saved_free, free);
+		goto out;
+	}
+
+	return 0;
+
+out:
+	ubifs_msg("saved lprops statistics dump");
+	dbg_dump_lstats(&d->saved_lst);
+	ubifs_get_lp_stats(c, &lst);
+	ubifs_msg("current lprops statistics dump");
+	dbg_dump_lstats(&d->saved_lst);
+	spin_lock(&c->space_lock);
+	dbg_dump_budg(c);
+	spin_unlock(&c->space_lock);
+	dump_stack();
+	return -EINVAL;
+}
+
+/**
  * dbg_check_synced_i_size - check synchronized inode size.
  * @inode: inode to check
  *
@@ -1349,7 +1407,7 @@ int dbg_check_tnc(struct ubifs_info *c, int extra)
  * @c: UBIFS file-system description object
  * @leaf_cb: called for each leaf node
  * @znode_cb: called for each indexing node
- * @priv: private date which is passed to callbacks
+ * @priv: private data which is passed to callbacks
  *
  * This function walks the UBIFS index and calls the @leaf_cb for each leaf
  * node and @znode_cb for each indexing node. Returns zero in case of success
@@ -2409,7 +2467,7 @@ void ubifs_debugging_exit(struct ubifs_info *c)
  * Root directory for UBIFS stuff in debugfs. Contains sub-directories which
  * contain the stuff specific to particular file-system mounts.
  */
-static struct dentry *debugfs_rootdir;
+static struct dentry *dfs_rootdir;
 
 /**
  * dbg_debugfs_init - initialize debugfs file-system.
@@ -2421,9 +2479,9 @@ static struct dentry *debugfs_rootdir;
  */
 int dbg_debugfs_init(void)
 {
-	debugfs_rootdir = debugfs_create_dir("ubifs", NULL);
-	if (IS_ERR(debugfs_rootdir)) {
-		int err = PTR_ERR(debugfs_rootdir);
+	dfs_rootdir = debugfs_create_dir("ubifs", NULL);
+	if (IS_ERR(dfs_rootdir)) {
+		int err = PTR_ERR(dfs_rootdir);
 		ubifs_err("cannot create \"ubifs\" debugfs directory, "
 			  "error %d\n", err);
 		return err;
@@ -2437,7 +2495,7 @@ int dbg_debugfs_init(void)
  */
 void dbg_debugfs_exit(void)
 {
-	debugfs_remove(debugfs_rootdir);
+	debugfs_remove(dfs_rootdir);
 }
 
 static int open_debugfs_file(struct inode *inode, struct file *file)
@@ -2452,13 +2510,13 @@ static ssize_t write_debugfs_file(struct file *file, const char __user *buf,
 	struct ubifs_info *c = file->private_data;
 	struct ubifs_debug_info *d = c->dbg;
 
-	if (file->f_path.dentry == d->dump_lprops)
+	if (file->f_path.dentry == d->dfs_dump_lprops)
 		dbg_dump_lprops(c);
-	else if (file->f_path.dentry == d->dump_budg) {
+	else if (file->f_path.dentry == d->dfs_dump_budg) {
 		spin_lock(&c->space_lock);
 		dbg_dump_budg(c);
 		spin_unlock(&c->space_lock);
-	} else if (file->f_path.dentry == d->dump_tnc) {
+	} else if (file->f_path.dentry == d->dfs_dump_tnc) {
 		mutex_lock(&c->tnc_mutex);
 		dbg_dump_tnc(c);
 		mutex_unlock(&c->tnc_mutex);
@@ -2469,7 +2527,7 @@ static ssize_t write_debugfs_file(struct file *file, const char __user *buf,
 	return count;
 }
 
-static const struct file_operations debugfs_fops = {
+static const struct file_operations dfs_fops = {
 	.open = open_debugfs_file,
 	.write = write_debugfs_file,
 	.owner = THIS_MODULE,
@@ -2494,36 +2552,32 @@ int dbg_debugfs_init_fs(struct ubifs_info *c)
 	struct dentry *dent;
 	struct ubifs_debug_info *d = c->dbg;
 
-	sprintf(d->debugfs_dir_name, "ubi%d_%d", c->vi.ubi_num, c->vi.vol_id);
-	d->debugfs_dir = debugfs_create_dir(d->debugfs_dir_name,
-					      debugfs_rootdir);
-	if (IS_ERR(d->debugfs_dir)) {
-		err = PTR_ERR(d->debugfs_dir);
+	sprintf(d->dfs_dir_name, "ubi%d_%d", c->vi.ubi_num, c->vi.vol_id);
+	d->dfs_dir = debugfs_create_dir(d->dfs_dir_name, dfs_rootdir);
+	if (IS_ERR(d->dfs_dir)) {
+		err = PTR_ERR(d->dfs_dir);
 		ubifs_err("cannot create \"%s\" debugfs directory, error %d\n",
-			  d->debugfs_dir_name, err);
+			  d->dfs_dir_name, err);
 		goto out;
 	}
 
 	fname = "dump_lprops";
-	dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
-				   &debugfs_fops);
+	dent = debugfs_create_file(fname, S_IWUGO, d->dfs_dir, c, &dfs_fops);
 	if (IS_ERR(dent))
 		goto out_remove;
-	d->dump_lprops = dent;
+	d->dfs_dump_lprops = dent;
 
 	fname = "dump_budg";
-	dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
-				   &debugfs_fops);
+	dent = debugfs_create_file(fname, S_IWUGO, d->dfs_dir, c, &dfs_fops);
 	if (IS_ERR(dent))
 		goto out_remove;
-	d->dump_budg = dent;
+	d->dfs_dump_budg = dent;
 
 	fname = "dump_tnc";
-	dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
-				   &debugfs_fops);
+	dent = debugfs_create_file(fname, S_IWUGO, d->dfs_dir, c, &dfs_fops);
 	if (IS_ERR(dent))
 		goto out_remove;
-	d->dump_tnc = dent;
+	d->dfs_dump_tnc = dent;
 
 	return 0;
 
@@ -2531,7 +2585,7 @@ out_remove:
 	err = PTR_ERR(dent);
 	ubifs_err("cannot create \"%s\" debugfs directory, error %d\n",
 		  fname, err);
-	debugfs_remove_recursive(d->debugfs_dir);
+	debugfs_remove_recursive(d->dfs_dir);
 out:
 	return err;
 }
@@ -2542,7 +2596,7 @@ out:
  */
 void dbg_debugfs_exit_fs(struct ubifs_info *c)
 {
-	debugfs_remove_recursive(c->dbg->debugfs_dir);
+	debugfs_remove_recursive(c->dbg->dfs_dir);
 }
 
 #endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index 9820d6999f7..c1cd73b2e06 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -41,15 +41,17 @@
  * @chk_lpt_wastage: used by LPT tree size checker
  * @chk_lpt_lebs: used by LPT tree size checker
  * @new_nhead_offs: used by LPT tree size checker
- * @new_ihead_lnum: used by debugging to check ihead_lnum
- * @new_ihead_offs: used by debugging to check ihead_offs
+ * @new_ihead_lnum: used by debugging to check @c->ihead_lnum
+ * @new_ihead_offs: used by debugging to check @c->ihead_offs
  *
- * debugfs_dir_name: name of debugfs directory containing this file-system's
- *                   files
- * debugfs_dir: direntry object of the file-system debugfs directory
- * dump_lprops: "dump lprops" debugfs knob
- * dump_budg: "dump budgeting information" debugfs knob
- * dump_tnc: "dump TNC" debugfs knob
+ * @saved_lst: saved lprops statistics (used by 'dbg_save_space_info()')
+ * @saved_free: saved free space (used by 'dbg_save_space_info()')
+ *
+ * dfs_dir_name: name of debugfs directory containing this file-system's files
+ * dfs_dir: direntry object of the file-system debugfs directory
+ * dfs_dump_lprops: "dump lprops" debugfs knob
+ * dfs_dump_budg: "dump budgeting information" debugfs knob
+ * dfs_dump_tnc: "dump TNC" debugfs knob
  */
 struct ubifs_debug_info {
 	void *buf;
@@ -69,11 +71,14 @@ struct ubifs_debug_info {
 	int new_ihead_lnum;
 	int new_ihead_offs;
 
-	char debugfs_dir_name[100];
-	struct dentry *debugfs_dir;
-	struct dentry *dump_lprops;
-	struct dentry *dump_budg;
-	struct dentry *dump_tnc;
+	struct ubifs_lp_stats saved_lst;
+	long long saved_free;
+
+	char dfs_dir_name[100];
+	struct dentry *dfs_dir;
+	struct dentry *dfs_dump_lprops;
+	struct dentry *dfs_dump_budg;
+	struct dentry *dfs_dump_tnc;
 };
 
 #define ubifs_assert(expr) do {                                                \
@@ -297,7 +302,8 @@ int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
 		   dbg_znode_callback znode_cb, void *priv);
 
 /* Checking functions */
-
+void dbg_save_space_info(struct ubifs_info *c);
+int dbg_check_space_info(struct ubifs_info *c);
 int dbg_check_lprops(struct ubifs_info *c);
 int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot);
 int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot);
@@ -439,6 +445,8 @@ void dbg_debugfs_exit_fs(struct ubifs_info *c);
 
 #define dbg_walk_index(c, leaf_cb, znode_cb, priv) 0
 #define dbg_old_index_check_init(c, zroot)         0
+#define dbg_save_space_info(c)                     ({})
+#define dbg_check_space_info(c)                    0
 #define dbg_check_old_index(c, zroot)              0
 #define dbg_check_cats(c)                          0
 #define dbg_check_ltab(c)                          0
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index f448ab1f9c3..f55d523c52b 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -482,30 +482,29 @@ static int ubifs_dir_release(struct inode *dir, struct file *file)
 }
 
 /**
- * lock_2_inodes - lock two UBIFS inodes.
+ * lock_2_inodes - a wrapper for locking two UBIFS inodes.
  * @inode1: first inode
  * @inode2: second inode
+ *
+ * We do not implement any tricks to guarantee strict lock ordering, because
+ * VFS has already done it for us on the @i_mutex. So this is just a simple
+ * wrapper function.
  */
 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
 {
-	if (inode1->i_ino < inode2->i_ino) {
-		mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_2);
-		mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_3);
-	} else {
-		mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
-		mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_3);
-	}
+	mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
+	mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
 }
 
 /**
- * unlock_2_inodes - unlock two UBIFS inodes inodes.
+ * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
  * @inode1: first inode
  * @inode2: second inode
  */
 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
 {
-	mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
 	mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
+	mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
 }
 
 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
@@ -527,6 +526,8 @@ static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
 	dbg_gen("dent '%.*s' to ino %lu (nlink %d) in dir ino %lu",
 		dentry->d_name.len, dentry->d_name.name, inode->i_ino,
 		inode->i_nlink, dir->i_ino);
+	ubifs_assert(mutex_is_locked(&dir->i_mutex));
+	ubifs_assert(mutex_is_locked(&inode->i_mutex));
 	err = dbg_check_synced_i_size(inode);
 	if (err)
 		return err;
@@ -580,6 +581,8 @@ static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
 	dbg_gen("dent '%.*s' from ino %lu (nlink %d) in dir ino %lu",
 		dentry->d_name.len, dentry->d_name.name, inode->i_ino,
 		inode->i_nlink, dir->i_ino);
+	ubifs_assert(mutex_is_locked(&dir->i_mutex));
+	ubifs_assert(mutex_is_locked(&inode->i_mutex));
 	err = dbg_check_synced_i_size(inode);
 	if (err)
 		return err;
@@ -667,7 +670,8 @@ static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
 
 	dbg_gen("directory '%.*s', ino %lu in dir ino %lu", dentry->d_name.len,
 		dentry->d_name.name, inode->i_ino, dir->i_ino);
-
+	ubifs_assert(mutex_is_locked(&dir->i_mutex));
+	ubifs_assert(mutex_is_locked(&inode->i_mutex));
 	err = check_dir_empty(c, dentry->d_inode);
 	if (err)
 		return err;
@@ -922,59 +926,30 @@ out_budg:
 }
 
 /**
- * lock_3_inodes - lock three UBIFS inodes for rename.
+ * lock_3_inodes - a wrapper for locking three UBIFS inodes.
  * @inode1: first inode
  * @inode2: second inode
  * @inode3: third inode
  *
- * For 'ubifs_rename()', @inode1 may be the same as @inode2 whereas @inode3 may
- * be null.
+ * This function is used for 'ubifs_rename()' and @inode1 may be the same as
+ * @inode2 whereas @inode3 may be %NULL.
+ *
+ * We do not implement any tricks to guarantee strict lock ordering, because
+ * VFS has already done it for us on the @i_mutex. So this is just a simple
+ * wrapper function.
  */
 static void lock_3_inodes(struct inode *inode1, struct inode *inode2,
 			  struct inode *inode3)
 {
-	struct inode *i1, *i2, *i3;
-
-	if (!inode3) {
-		if (inode1 != inode2) {
-			lock_2_inodes(inode1, inode2);
-			return;
-		}
-		mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
-		return;
-	}
-
-	if (inode1 == inode2) {
-		lock_2_inodes(inode1, inode3);
-		return;
-	}
-
-	/* 3 different inodes */
-	if (inode1 < inode2) {
-		i3 = inode2;
-		if (inode1 < inode3) {
-			i1 = inode1;
-			i2 = inode3;
-		} else {
-			i1 = inode3;
-			i2 = inode1;
-		}
-	} else {
-		i3 = inode1;
-		if (inode2 < inode3) {
-			i1 = inode2;
-			i2 = inode3;
-		} else {
-			i1 = inode3;
-			i2 = inode2;
-		}
-	}
-	mutex_lock_nested(&ubifs_inode(i1)->ui_mutex, WB_MUTEX_1);
-	lock_2_inodes(i2, i3);
+	mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
+	if (inode2 != inode1)
+		mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
+	if (inode3)
+		mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
 }
 
 /**
- * unlock_3_inodes - unlock three UBIFS inodes for rename.
+ * unlock_3_inodes - a wrapper for unlocking three UBIFS inodes for rename.
  * @inode1: first inode
  * @inode2: second inode
  * @inode3: third inode
@@ -982,11 +957,11 @@ static void lock_3_inodes(struct inode *inode1, struct inode *inode2,
 static void unlock_3_inodes(struct inode *inode1, struct inode *inode2,
 			    struct inode *inode3)
 {
-	mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
-	if (inode1 != inode2)
-		mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
 	if (inode3)
 		mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
+	if (inode1 != inode2)
+		mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
+	mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
 }
 
 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
@@ -1020,6 +995,11 @@ static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
 		"dir ino %lu", old_dentry->d_name.len, old_dentry->d_name.name,
 		old_inode->i_ino, old_dir->i_ino, new_dentry->d_name.len,
 		new_dentry->d_name.name, new_dir->i_ino);
+	ubifs_assert(mutex_is_locked(&old_dir->i_mutex));
+	ubifs_assert(mutex_is_locked(&new_dir->i_mutex));
+	if (unlink)
+		ubifs_assert(mutex_is_locked(&new_inode->i_mutex));
+
 
 	if (unlink && is_dir) {
 		err = check_dir_empty(c, new_inode);
@@ -1199,7 +1179,7 @@ int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 	return 0;
 }
 
-struct inode_operations ubifs_dir_inode_operations = {
+const struct inode_operations ubifs_dir_inode_operations = {
 	.lookup      = ubifs_lookup,
 	.create      = ubifs_create,
 	.link        = ubifs_link,
@@ -1219,7 +1199,7 @@ struct inode_operations ubifs_dir_inode_operations = {
 #endif
 };
 
-struct file_operations ubifs_dir_operations = {
+const struct file_operations ubifs_dir_operations = {
 	.llseek         = ubifs_dir_llseek,
 	.release        = ubifs_dir_release,
 	.read           = generic_read_dir,
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index bf37374567f..93b6de51f26 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -432,7 +432,6 @@ static int ubifs_write_begin(struct file *file, struct address_space *mapping,
 	int uninitialized_var(err), appending = !!(pos + len > inode->i_size);
 	struct page *page;
 
-
 	ubifs_assert(ubifs_inode(inode)->ui_size == inode->i_size);
 
 	if (unlikely(c->ro_media))
@@ -1541,7 +1540,7 @@ static int ubifs_file_mmap(struct file *file, struct vm_area_struct *vma)
 	return 0;
 }
 
-struct address_space_operations ubifs_file_address_operations = {
+const struct address_space_operations ubifs_file_address_operations = {
 	.readpage       = ubifs_readpage,
 	.writepage      = ubifs_writepage,
 	.write_begin    = ubifs_write_begin,
@@ -1551,7 +1550,7 @@ struct address_space_operations ubifs_file_address_operations = {
 	.releasepage    = ubifs_releasepage,
 };
 
-struct inode_operations ubifs_file_inode_operations = {
+const struct inode_operations ubifs_file_inode_operations = {
 	.setattr     = ubifs_setattr,
 	.getattr     = ubifs_getattr,
 #ifdef CONFIG_UBIFS_FS_XATTR
@@ -1562,14 +1561,14 @@ struct inode_operations ubifs_file_inode_operations = {
 #endif
 };
 
-struct inode_operations ubifs_symlink_inode_operations = {
+const struct inode_operations ubifs_symlink_inode_operations = {
 	.readlink    = generic_readlink,
 	.follow_link = ubifs_follow_link,
 	.setattr     = ubifs_setattr,
 	.getattr     = ubifs_getattr,
 };
 
-struct file_operations ubifs_file_operations = {
+const struct file_operations ubifs_file_operations = {
 	.llseek         = generic_file_llseek,
 	.read           = do_sync_read,
 	.write          = do_sync_write,
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index 9832f9abe28..a711d33b3d3 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -31,6 +31,26 @@
  * to be reused. Garbage collection will cause the number of dirty index nodes
  * to grow, however sufficient space is reserved for the index to ensure the
  * commit will never run out of space.
+ *
+ * Notes about dead watermark. At current UBIFS implementation we assume that
+ * LEBs which have less than @c->dead_wm bytes of free + dirty space are full
+ * and not worth garbage-collecting. The dead watermark is one min. I/O unit
+ * size, or min. UBIFS node size, depending on what is greater. Indeed, UBIFS
+ * Garbage Collector has to synchronize the GC head's write buffer before
+ * returning, so this is about wasting one min. I/O unit. However, UBIFS GC can
+ * actually reclaim even very small pieces of dirty space by garbage collecting
+ * enough dirty LEBs, but we do not bother doing this at this implementation.
+ *
+ * Notes about dark watermark. The results of GC work depends on how big are
+ * the UBIFS nodes GC deals with. Large nodes make GC waste more space. Indeed,
+ * if GC move data from LEB A to LEB B and nodes in LEB A are large, GC would
+ * have to waste large pieces of free space at the end of LEB B, because nodes
+ * from LEB A would not fit. And the worst situation is when all nodes are of
+ * maximum size. So dark watermark is the amount of free + dirty space in LEB
+ * which are guaranteed to be reclaimable. If LEB has less space, the GC migh
+ * be unable to reclaim it. So, LEBs with free + dirty greater than dark
+ * watermark are "good" LEBs from GC's point of few. The other LEBs are not so
+ * good, and GC takes extra care when moving them.
  */
 
 #include <linux/pagemap.h>
@@ -381,7 +401,7 @@ int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp)
 
 		/*
 		 * Don't release the LEB until after the next commit, because
-		 * it may contain date which is needed for recovery. So
+		 * it may contain data which is needed for recovery. So
 		 * although we freed this LEB, it will become usable only after
 		 * the commit.
 		 */
@@ -810,8 +830,9 @@ out:
  * ubifs_destroy_idx_gc - destroy idx_gc list.
  * @c: UBIFS file-system description object
  *
- * This function destroys the idx_gc list. It is called when unmounting or
- * remounting read-only so locks are not needed.
+ * This function destroys the @c->idx_gc list. It is called when unmounting
+ * so locks are not needed. Returns zero in case of success and a negative
+ * error code in case of failure.
  */
 void ubifs_destroy_idx_gc(struct ubifs_info *c)
 {
@@ -824,7 +845,6 @@ void ubifs_destroy_idx_gc(struct ubifs_info *c)
 		list_del(&idx_gc->list);
 		kfree(idx_gc);
 	}
-
 }
 
 /**
diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c
index 01682713af6..e8e632a1dcd 100644
--- a/fs/ubifs/io.c
+++ b/fs/ubifs/io.c
@@ -29,7 +29,7 @@
  * would have been wasted for padding to the nearest minimal I/O unit boundary.
  * Instead, data first goes to the write-buffer and is flushed when the
  * buffer is full or when it is not used for some time (by timer). This is
- * similarto the mechanism is used by JFFS2.
+ * similar to the mechanism is used by JFFS2.
  *
  * Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by
  * mutexes defined inside these objects. Since sometimes upper-level code
@@ -75,7 +75,7 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
  * @lnum: logical eraseblock number
  * @offs: offset within the logical eraseblock
  * @quiet: print no messages
- * @chk_crc: indicates whether to always check the CRC
+ * @must_chk_crc: indicates whether to always check the CRC
  *
  * This function checks node magic number and CRC checksum. This function also
  * validates node length to prevent UBIFS from becoming crazy when an attacker
@@ -83,11 +83,17 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
  * node length in the common header could cause UBIFS to read memory outside of
  * allocated buffer when checking the CRC checksum.
  *
- * This function returns zero in case of success %-EUCLEAN in case of bad CRC
- * or magic.
+ * This function may skip data nodes CRC checking if @c->no_chk_data_crc is
+ * true, which is controlled by corresponding UBIFS mount option. However, if
+ * @must_chk_crc is true, then @c->no_chk_data_crc is ignored and CRC is
+ * checked. Similarly, if @c->always_chk_crc is true, @c->no_chk_data_crc is
+ * ignored and CRC is checked.
+ *
+ * This function returns zero in case of success and %-EUCLEAN in case of bad
+ * CRC or magic.
  */
 int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
-		     int offs, int quiet, int chk_crc)
+		     int offs, int quiet, int must_chk_crc)
 {
 	int err = -EINVAL, type, node_len;
 	uint32_t crc, node_crc, magic;
@@ -123,9 +129,9 @@ int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
 		   node_len > c->ranges[type].max_len)
 		goto out_len;
 
-	if (!chk_crc && type == UBIFS_DATA_NODE && !c->always_chk_crc)
-		if (c->no_chk_data_crc)
-			return 0;
+	if (!must_chk_crc && type == UBIFS_DATA_NODE && !c->always_chk_crc &&
+	     c->no_chk_data_crc)
+		return 0;
 
 	crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
 	node_crc = le32_to_cpu(ch->crc);
diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c
index 9b7c54e0cd2..a11ca0958a2 100644
--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -208,7 +208,7 @@ again:
 	offs = 0;
 
 out:
-	err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs, UBI_SHORTTERM);
+	err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs, wbuf->dtype);
 	if (err)
 		goto out_unlock;
 
diff --git a/fs/ubifs/lprops.c b/fs/ubifs/lprops.c
index dfd2bcece27..4cdd284dea5 100644
--- a/fs/ubifs/lprops.c
+++ b/fs/ubifs/lprops.c
@@ -635,10 +635,10 @@ const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
  * @c: UBIFS file-system description object
  * @st: return statistics
  */
-void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *st)
+void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
 {
 	spin_lock(&c->space_lock);
-	memcpy(st, &c->lst, sizeof(struct ubifs_lp_stats));
+	memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
 	spin_unlock(&c->space_lock);
 }
 
@@ -678,6 +678,9 @@ int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 
 out:
 	ubifs_release_lprops(c);
+	if (err)
+		ubifs_err("cannot change properties of LEB %d, error %d",
+			  lnum, err);
 	return err;
 }
 
@@ -714,6 +717,9 @@ int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 
 out:
 	ubifs_release_lprops(c);
+	if (err)
+		ubifs_err("cannot update properties of LEB %d, error %d",
+			  lnum, err);
 	return err;
 }
 
@@ -737,6 +743,8 @@ int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
 	lpp = ubifs_lpt_lookup(c, lnum);
 	if (IS_ERR(lpp)) {
 		err = PTR_ERR(lpp);
+		ubifs_err("cannot read properties of LEB %d, error %d",
+			  lnum, err);
 		goto out;
 	}
 
diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
index 96ca9570717..3216a1f277f 100644
--- a/fs/ubifs/lpt_commit.c
+++ b/fs/ubifs/lpt_commit.c
@@ -556,23 +556,23 @@ no_space:
 }
 
 /**
- * next_pnode - find next pnode.
+ * next_pnode_to_dirty - find next pnode to dirty.
  * @c: UBIFS file-system description object
  * @pnode: pnode
  *
- * This function returns the next pnode or %NULL if there are no more pnodes.
+ * This function returns the next pnode to dirty or %NULL if there are no more
+ * pnodes.  Note that pnodes that have never been written (lnum == 0) are
+ * skipped.
  */
-static struct ubifs_pnode *next_pnode(struct ubifs_info *c,
-				      struct ubifs_pnode *pnode)
+static struct ubifs_pnode *next_pnode_to_dirty(struct ubifs_info *c,
+					       struct ubifs_pnode *pnode)
 {
 	struct ubifs_nnode *nnode;
 	int iip;
 
 	/* Try to go right */
 	nnode = pnode->parent;
-	iip = pnode->iip + 1;
-	if (iip < UBIFS_LPT_FANOUT) {
-		/* We assume here that LEB zero is never an LPT LEB */
+	for (iip = pnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
 		if (nnode->nbranch[iip].lnum)
 			return ubifs_get_pnode(c, nnode, iip);
 	}
@@ -583,8 +583,11 @@ static struct ubifs_pnode *next_pnode(struct ubifs_info *c,
 		nnode = nnode->parent;
 		if (!nnode)
 			return NULL;
-		/* We assume here that LEB zero is never an LPT LEB */
-	} while (iip >= UBIFS_LPT_FANOUT || !nnode->nbranch[iip].lnum);
+		for (; iip < UBIFS_LPT_FANOUT; iip++) {
+			if (nnode->nbranch[iip].lnum)
+				break;
+		}
+       } while (iip >= UBIFS_LPT_FANOUT);
 
 	/* Go right */
 	nnode = ubifs_get_nnode(c, nnode, iip);
@@ -593,12 +596,29 @@ static struct ubifs_pnode *next_pnode(struct ubifs_info *c,
 
 	/* Go down to level 1 */
 	while (nnode->level > 1) {
-		nnode = ubifs_get_nnode(c, nnode, 0);
+		for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++) {
+			if (nnode->nbranch[iip].lnum)
+				break;
+		}
+		if (iip >= UBIFS_LPT_FANOUT) {
+			/*
+			 * Should not happen, but we need to keep going
+			 * if it does.
+			 */
+			iip = 0;
+		}
+		nnode = ubifs_get_nnode(c, nnode, iip);
 		if (IS_ERR(nnode))
 			return (void *)nnode;
 	}
 
-	return ubifs_get_pnode(c, nnode, 0);
+	for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++)
+		if (nnode->nbranch[iip].lnum)
+			break;
+	if (iip >= UBIFS_LPT_FANOUT)
+		/* Should not happen, but we need to keep going if it does */
+		iip = 0;
+	return ubifs_get_pnode(c, nnode, iip);
 }
 
 /**
@@ -688,7 +708,7 @@ static int make_tree_dirty(struct ubifs_info *c)
 	pnode = pnode_lookup(c, 0);
 	while (pnode) {
 		do_make_pnode_dirty(c, pnode);
-		pnode = next_pnode(c, pnode);
+		pnode = next_pnode_to_dirty(c, pnode);
 		if (IS_ERR(pnode))
 			return PTR_ERR(pnode);
 	}
diff --git a/fs/ubifs/master.c b/fs/ubifs/master.c
index 71d5493bf56..a88f33801b9 100644
--- a/fs/ubifs/master.c
+++ b/fs/ubifs/master.c
@@ -354,7 +354,7 @@ int ubifs_write_master(struct ubifs_info *c)
 	int err, lnum, offs, len;
 
 	if (c->ro_media)
-		return -EINVAL;
+		return -EROFS;
 
 	lnum = UBIFS_MST_LNUM;
 	offs = c->mst_offs + c->mst_node_alsz;
diff --git a/fs/ubifs/orphan.c b/fs/ubifs/orphan.c
index 9e6f403f170..152a7b34a14 100644
--- a/fs/ubifs/orphan.c
+++ b/fs/ubifs/orphan.c
@@ -46,7 +46,7 @@
  * Orphans are accumulated in a rb-tree. When an inode's link count drops to
  * zero, the inode number is added to the rb-tree. It is removed from the tree
  * when the inode is deleted.  Any new orphans that are in the orphan tree when
- * the commit is run, are written to the orphan area in 1 or more orph nodes.
+ * the commit is run, are written to the orphan area in 1 or more orphan nodes.
  * If the orphan area is full, it is consolidated to make space.  There is
  * always enough space because validation prevents the user from creating more
  * than the maximum number of orphans allowed.
@@ -231,7 +231,7 @@ static int tot_avail_orphs(struct ubifs_info *c)
 }
 
 /**
- * do_write_orph_node - write a node
+ * do_write_orph_node - write a node to the orphan head.
  * @c: UBIFS file-system description object
  * @len: length of node
  * @atomic: write atomically
@@ -264,11 +264,11 @@ static int do_write_orph_node(struct ubifs_info *c, int len, int atomic)
 }
 
 /**
- * write_orph_node - write an orph node
+ * write_orph_node - write an orphan node.
  * @c: UBIFS file-system description object
  * @atomic: write atomically
  *
- * This function builds an orph node from the cnext list and writes it to the
+ * This function builds an orphan node from the cnext list and writes it to the
  * orphan head. On success, %0 is returned, otherwise a negative error code
  * is returned.
  */
@@ -326,11 +326,11 @@ static int write_orph_node(struct ubifs_info *c, int atomic)
 }
 
 /**
- * write_orph_nodes - write orph nodes until there are no more to commit
+ * write_orph_nodes - write orphan nodes until there are no more to commit.
  * @c: UBIFS file-system description object
  * @atomic: write atomically
  *
- * This function writes orph nodes for all the orphans to commit. On success,
+ * This function writes orphan nodes for all the orphans to commit. On success,
  * %0 is returned, otherwise a negative error code is returned.
  */
 static int write_orph_nodes(struct ubifs_info *c, int atomic)
@@ -478,14 +478,14 @@ int ubifs_orphan_end_commit(struct ubifs_info *c)
 }
 
 /**
- * clear_orphans - erase all LEBs used for orphans.
+ * ubifs_clear_orphans - erase all LEBs used for orphans.
  * @c: UBIFS file-system description object
  *
  * If recovery is not required, then the orphans from the previous session
  * are not needed. This function locates the LEBs used to record
  * orphans, and un-maps them.
  */
-static int clear_orphans(struct ubifs_info *c)
+int ubifs_clear_orphans(struct ubifs_info *c)
 {
 	int lnum, err;
 
@@ -547,9 +547,9 @@ static int insert_dead_orphan(struct ubifs_info *c, ino_t inum)
  * do_kill_orphans - remove orphan inodes from the index.
  * @c: UBIFS file-system description object
  * @sleb: scanned LEB
- * @last_cmt_no: cmt_no of last orph node read is passed and returned here
+ * @last_cmt_no: cmt_no of last orphan node read is passed and returned here
  * @outofdate: whether the LEB is out of date is returned here
- * @last_flagged: whether the end orph node is encountered
+ * @last_flagged: whether the end orphan node is encountered
  *
  * This function is a helper to the 'kill_orphans()' function. It goes through
  * every orphan node in a LEB and for every inode number recorded, removes
@@ -580,8 +580,8 @@ static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
 		/*
 		 * The commit number on the master node may be less, because
 		 * of a failed commit. If there are several failed commits in a
-		 * row, the commit number written on orph nodes will continue to
-		 * increase (because the commit number is adjusted here) even
+		 * row, the commit number written on orphan nodes will continue
+		 * to increase (because the commit number is adjusted here) even
 		 * though the commit number on the master node stays the same
 		 * because the master node has not been re-written.
 		 */
@@ -589,9 +589,9 @@ static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
 			c->cmt_no = cmt_no;
 		if (cmt_no < *last_cmt_no && *last_flagged) {
 			/*
-			 * The last orph node had a higher commit number and was
-			 * flagged as the last written for that commit number.
-			 * That makes this orph node, out of date.
+			 * The last orphan node had a higher commit number and
+			 * was flagged as the last written for that commit
+			 * number. That makes this orphan node, out of date.
 			 */
 			if (!first) {
 				ubifs_err("out of order commit number %llu in "
@@ -658,10 +658,10 @@ static int kill_orphans(struct ubifs_info *c)
 	/*
 	 * Orph nodes always start at c->orph_first and are written to each
 	 * successive LEB in turn. Generally unused LEBs will have been unmapped
-	 * but may contain out of date orph nodes if the unmap didn't go
-	 * through. In addition, the last orph node written for each commit is
+	 * but may contain out of date orphan nodes if the unmap didn't go
+	 * through. In addition, the last orphan node written for each commit is
 	 * marked (top bit of orph->cmt_no is set to 1). It is possible that
-	 * there are orph nodes from the next commit (i.e. the commit did not
+	 * there are orphan nodes from the next commit (i.e. the commit did not
 	 * complete successfully). In that case, no orphans will have been lost
 	 * due to the way that orphans are written, and any orphans added will
 	 * be valid orphans anyway and so can be deleted.
@@ -718,7 +718,7 @@ int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only)
 	if (unclean)
 		err = kill_orphans(c);
 	else if (!read_only)
-		err = clear_orphans(c);
+		err = ubifs_clear_orphans(c);
 
 	return err;
 }
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 89556ee7251..1182b66a549 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -397,6 +397,7 @@ static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	buf->f_namelen = UBIFS_MAX_NLEN;
 	buf->f_fsid.val[0] = le32_to_cpu(uuid[0]) ^ le32_to_cpu(uuid[2]);
 	buf->f_fsid.val[1] = le32_to_cpu(uuid[1]) ^ le32_to_cpu(uuid[3]);
+	ubifs_assert(buf->f_bfree <= c->block_cnt);
 	return 0;
 }
 
@@ -432,33 +433,24 @@ static int ubifs_sync_fs(struct super_block *sb, int wait)
 	int i, err;
 	struct ubifs_info *c = sb->s_fs_info;
 	struct writeback_control wbc = {
-		.sync_mode   = wait ? WB_SYNC_ALL : WB_SYNC_NONE,
+		.sync_mode   = WB_SYNC_ALL,
 		.range_start = 0,
 		.range_end   = LLONG_MAX,
 		.nr_to_write = LONG_MAX,
 	};
 
 	/*
-	 * Note by akpm about WB_SYNC_NONE used above: zero @wait is just an
-	 * advisory thing to help the file system shove lots of data into the
-	 * queues. If some gets missed then it'll be picked up on the second
+	 * Zero @wait is just an advisory thing to help the file system shove
+	 * lots of data into the queues, and there will be the second
 	 * '->sync_fs()' call, with non-zero @wait.
 	 */
+	if (!wait)
+		return 0;
 
 	if (sb->s_flags & MS_RDONLY)
 		return 0;
 
 	/*
-	 * Synchronize write buffers, because 'ubifs_run_commit()' does not
-	 * do this if it waits for an already running commit.
-	 */
-	for (i = 0; i < c->jhead_cnt; i++) {
-		err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
-		if (err)
-			return err;
-	}
-
-	/*
 	 * VFS calls '->sync_fs()' before synchronizing all dirty inodes and
 	 * pages, so synchronize them first, then commit the journal. Strictly
 	 * speaking, it is not necessary to commit the journal here,
@@ -469,6 +461,16 @@ static int ubifs_sync_fs(struct super_block *sb, int wait)
 	 */
 	generic_sync_sb_inodes(sb, &wbc);
 
+	/*
+	 * Synchronize write buffers, because 'ubifs_run_commit()' does not
+	 * do this if it waits for an already running commit.
+	 */
+	for (i = 0; i < c->jhead_cnt; i++) {
+		err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+		if (err)
+			return err;
+	}
+
 	err = ubifs_run_commit(c);
 	if (err)
 		return err;
@@ -572,15 +574,8 @@ static int init_constants_early(struct ubifs_info *c)
 	c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX;
 
 	/*
-	 * Initialize dead and dark LEB space watermarks.
-	 *
-	 * Dead space is the space which cannot be used. Its watermark is
-	 * equivalent to min. I/O unit or minimum node size if it is greater
-	 * then min. I/O unit.
-	 *
-	 * Dark space is the space which might be used, or might not, depending
-	 * on which node should be written to the LEB. Its watermark is
-	 * equivalent to maximum UBIFS node size.
+	 * Initialize dead and dark LEB space watermarks. See gc.c for comments
+	 * about these values.
 	 */
 	c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
 	c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);
@@ -741,12 +736,12 @@ static void init_constants_master(struct ubifs_info *c)
  * take_gc_lnum - reserve GC LEB.
  * @c: UBIFS file-system description object
  *
- * This function ensures that the LEB reserved for garbage collection is
- * unmapped and is marked as "taken" in lprops. We also have to set free space
- * to LEB size and dirty space to zero, because lprops may contain out-of-date
- * information if the file-system was un-mounted before it has been committed.
- * This function returns zero in case of success and a negative error code in
- * case of failure.
+ * This function ensures that the LEB reserved for garbage collection is marked
+ * as "taken" in lprops. We also have to set free space to LEB size and dirty
+ * space to zero, because lprops may contain out-of-date information if the
+ * file-system was un-mounted before it has been committed. This function
+ * returns zero in case of success and a negative error code in case of
+ * failure.
  */
 static int take_gc_lnum(struct ubifs_info *c)
 {
@@ -757,10 +752,6 @@ static int take_gc_lnum(struct ubifs_info *c)
 		return -EINVAL;
 	}
 
-	err = ubifs_leb_unmap(c, c->gc_lnum);
-	if (err)
-		return err;
-
 	/* And we have to tell lprops that this LEB is taken */
 	err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0,
 				  LPROPS_TAKEN, 0, 0);
@@ -966,13 +957,16 @@ static int ubifs_parse_options(struct ubifs_info *c, char *options,
 
 		token = match_token(p, tokens, args);
 		switch (token) {
+		/*
+		 * %Opt_fast_unmount and %Opt_norm_unmount options are ignored.
+		 * We accepte them in order to be backware-compatible. But this
+		 * should be removed at some point.
+		 */
 		case Opt_fast_unmount:
 			c->mount_opts.unmount_mode = 2;
-			c->fast_unmount = 1;
 			break;
 		case Opt_norm_unmount:
 			c->mount_opts.unmount_mode = 1;
-			c->fast_unmount = 0;
 			break;
 		case Opt_bulk_read:
 			c->mount_opts.bulk_read = 2;
@@ -1094,12 +1088,7 @@ static int check_free_space(struct ubifs_info *c)
 		ubifs_err("insufficient free space to mount in read/write mode");
 		dbg_dump_budg(c);
 		dbg_dump_lprops(c);
-		/*
-		 * We return %-EINVAL instead of %-ENOSPC because it seems to
-		 * be the closest error code mentioned in the mount function
-		 * documentation.
-		 */
-		return -EINVAL;
+		return -ENOSPC;
 	}
 	return 0;
 }
@@ -1286,10 +1275,19 @@ static int mount_ubifs(struct ubifs_info *c)
 			if (err)
 				goto out_orphans;
 			err = ubifs_rcvry_gc_commit(c);
-		} else
+		} else {
 			err = take_gc_lnum(c);
-		if (err)
-			goto out_orphans;
+			if (err)
+				goto out_orphans;
+
+			/*
+			 * GC LEB may contain garbage if there was an unclean
+			 * reboot, and it should be un-mapped.
+			 */
+			err = ubifs_leb_unmap(c, c->gc_lnum);
+			if (err)
+				return err;
+		}
 
 		err = dbg_check_lprops(c);
 		if (err)
@@ -1298,6 +1296,16 @@ static int mount_ubifs(struct ubifs_info *c)
 		err = ubifs_recover_size(c);
 		if (err)
 			goto out_orphans;
+	} else {
+		/*
+		 * Even if we mount read-only, we have to set space in GC LEB
+		 * to proper value because this affects UBIFS free space
+		 * reporting. We do not want to have a situation when
+		 * re-mounting from R/O to R/W changes amount of free space.
+		 */
+		err = take_gc_lnum(c);
+		if (err)
+			goto out_orphans;
 	}
 
 	spin_lock(&ubifs_infos_lock);
@@ -1310,14 +1318,17 @@ static int mount_ubifs(struct ubifs_info *c)
 		else {
 			c->need_recovery = 0;
 			ubifs_msg("recovery completed");
+			/* GC LEB has to be empty and taken at this point */
+			ubifs_assert(c->lst.taken_empty_lebs == 1);
 		}
-	}
+	} else
+		ubifs_assert(c->lst.taken_empty_lebs == 1);
 
-	err = dbg_debugfs_init_fs(c);
+	err = dbg_check_filesystem(c);
 	if (err)
 		goto out_infos;
 
-	err = dbg_check_filesystem(c);
+	err = dbg_debugfs_init_fs(c);
 	if (err)
 		goto out_infos;
 
@@ -1351,7 +1362,6 @@ static int mount_ubifs(struct ubifs_info *c)
 	       c->uuid[4], c->uuid[5], c->uuid[6], c->uuid[7],
 	       c->uuid[8], c->uuid[9], c->uuid[10], c->uuid[11],
 	       c->uuid[12], c->uuid[13], c->uuid[14], c->uuid[15]);
-	dbg_msg("fast unmount:        %d", c->fast_unmount);
 	dbg_msg("big_lpt              %d", c->big_lpt);
 	dbg_msg("log LEBs:            %d (%d - %d)",
 		c->log_lebs, UBIFS_LOG_LNUM, c->log_last);
@@ -1475,10 +1485,8 @@ static int ubifs_remount_rw(struct ubifs_info *c)
 {
 	int err, lnum;
 
-	if (c->ro_media)
-		return -EINVAL;
-
 	mutex_lock(&c->umount_mutex);
+	dbg_save_space_info(c);
 	c->remounting_rw = 1;
 	c->always_chk_crc = 1;
 
@@ -1514,6 +1522,12 @@ static int ubifs_remount_rw(struct ubifs_info *c)
 		err = ubifs_recover_inl_heads(c, c->sbuf);
 		if (err)
 			goto out;
+	} else {
+		/* A readonly mount is not allowed to have orphans */
+		ubifs_assert(c->tot_orphans == 0);
+		err = ubifs_clear_orphans(c);
+		if (err)
+			goto out;
 	}
 
 	if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) {
@@ -1569,7 +1583,7 @@ static int ubifs_remount_rw(struct ubifs_info *c)
 	if (c->need_recovery)
 		err = ubifs_rcvry_gc_commit(c);
 	else
-		err = take_gc_lnum(c);
+		err = ubifs_leb_unmap(c, c->gc_lnum);
 	if (err)
 		goto out;
 
@@ -1582,8 +1596,9 @@ static int ubifs_remount_rw(struct ubifs_info *c)
 	c->vfs_sb->s_flags &= ~MS_RDONLY;
 	c->remounting_rw = 0;
 	c->always_chk_crc = 0;
+	err = dbg_check_space_info(c);
 	mutex_unlock(&c->umount_mutex);
-	return 0;
+	return err;
 
 out:
 	vfree(c->orph_buf);
@@ -1603,43 +1618,18 @@ out:
 }
 
 /**
- * commit_on_unmount - commit the journal when un-mounting.
- * @c: UBIFS file-system description object
- *
- * This function is called during un-mounting and re-mounting, and it commits
- * the journal unless the "fast unmount" mode is enabled.
- */
-static void commit_on_unmount(struct ubifs_info *c)
-{
-	struct super_block *sb = c->vfs_sb;
-	long long bud_bytes;
-
-	/*
-	 * This function is called before the background thread is stopped, so
-	 * we may race with ongoing commit, which means we have to take
-	 * @c->bud_lock to access @c->bud_bytes.
-	 */
-	spin_lock(&c->buds_lock);
-	bud_bytes = c->bud_bytes;
-	spin_unlock(&c->buds_lock);
-
-	if (!c->fast_unmount && !(sb->s_flags & MS_RDONLY) && bud_bytes)
-		ubifs_run_commit(c);
-}
-
-/**
  * ubifs_remount_ro - re-mount in read-only mode.
  * @c: UBIFS file-system description object
  *
- * We rely on VFS to have stopped writing. Possibly the background thread could
- * be running a commit, however kthread_stop will wait in that case.
+ * We assume VFS has stopped writing. Possibly the background thread could be
+ * running a commit, however kthread_stop will wait in that case.
  */
 static void ubifs_remount_ro(struct ubifs_info *c)
 {
 	int i, err;
 
 	ubifs_assert(!c->need_recovery);
-	commit_on_unmount(c);
+	ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY));
 
 	mutex_lock(&c->umount_mutex);
 	if (c->bgt) {
@@ -1647,27 +1637,29 @@ static void ubifs_remount_ro(struct ubifs_info *c)
 		c->bgt = NULL;
 	}
 
+	dbg_save_space_info(c);
+
 	for (i = 0; i < c->jhead_cnt; i++) {
 		ubifs_wbuf_sync(&c->jheads[i].wbuf);
 		del_timer_sync(&c->jheads[i].wbuf.timer);
 	}
 
-	if (!c->ro_media) {
-		c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
-		c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
-		c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
-		err = ubifs_write_master(c);
-		if (err)
-			ubifs_ro_mode(c, err);
-	}
+	c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
+	c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
+	c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
+	err = ubifs_write_master(c);
+	if (err)
+		ubifs_ro_mode(c, err);
 
-	ubifs_destroy_idx_gc(c);
 	free_wbufs(c);
 	vfree(c->orph_buf);
 	c->orph_buf = NULL;
 	vfree(c->ileb_buf);
 	c->ileb_buf = NULL;
 	ubifs_lpt_free(c, 1);
+	err = dbg_check_space_info(c);
+	if (err)
+		ubifs_ro_mode(c, err);
 	mutex_unlock(&c->umount_mutex);
 }
 
@@ -1760,11 +1752,20 @@ static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
 	}
 
 	if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
+		if (c->ro_media) {
+			ubifs_msg("cannot re-mount due to prior errors");
+			return -EROFS;
+		}
 		err = ubifs_remount_rw(c);
 		if (err)
 			return err;
-	} else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY))
+	} else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY)) {
+		if (c->ro_media) {
+			ubifs_msg("cannot re-mount due to prior errors");
+			return -EROFS;
+		}
 		ubifs_remount_ro(c);
+	}
 
 	if (c->bulk_read == 1)
 		bu_init(c);
@@ -1774,10 +1775,11 @@ static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
 		c->bu.buf = NULL;
 	}
 
+	ubifs_assert(c->lst.taken_empty_lebs == 1);
 	return 0;
 }
 
-struct super_operations ubifs_super_operations = {
+const struct super_operations ubifs_super_operations = {
 	.alloc_inode   = ubifs_alloc_inode,
 	.destroy_inode = ubifs_destroy_inode,
 	.put_super     = ubifs_put_super,
@@ -2044,15 +2046,6 @@ out_close:
 
 static void ubifs_kill_sb(struct super_block *sb)
 {
-	struct ubifs_info *c = sb->s_fs_info;
-
-	/*
-	 * We do 'commit_on_unmount()' here instead of 'ubifs_put_super()'
-	 * in order to be outside BKL.
-	 */
-	if (sb->s_root)
-		commit_on_unmount(c);
-	/* The un-mount routine is actually done in put_super() */
 	generic_shutdown_super(sb);
 }
 
diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c
index f7e36f54552..fa28a84c6a1 100644
--- a/fs/ubifs/tnc.c
+++ b/fs/ubifs/tnc.c
@@ -443,6 +443,11 @@ static int tnc_read_node_nm(struct ubifs_info *c, struct ubifs_zbranch *zbr,
  * This function performs that same function as ubifs_read_node except that
  * it does not require that there is actually a node present and instead
  * the return code indicates if a node was read.
+ *
+ * Note, this function does not check CRC of data nodes if @c->no_chk_data_crc
+ * is true (it is controlled by corresponding mount option). However, if
+ * @c->always_chk_crc is true, @c->no_chk_data_crc is ignored and CRC is always
+ * checked.
  */
 static int try_read_node(const struct ubifs_info *c, void *buf, int type,
 			 int len, int lnum, int offs)
@@ -470,9 +475,8 @@ static int try_read_node(const struct ubifs_info *c, void *buf, int type,
 	if (node_len != len)
 		return 0;
 
-	if (type == UBIFS_DATA_NODE && !c->always_chk_crc)
-		if (c->no_chk_data_crc)
-			return 0;
+	if (type == UBIFS_DATA_NODE && !c->always_chk_crc && c->no_chk_data_crc)
+		return 1;
 
 	crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
 	node_crc = le32_to_cpu(ch->crc);
@@ -1506,7 +1510,7 @@ out:
  *
  * Note, if the bulk-read buffer length (@bu->buf_len) is known, this function
  * makes sure bulk-read nodes fit the buffer. Otherwise, this function prepares
- * maxumum possible amount of nodes for bulk-read.
+ * maximum possible amount of nodes for bulk-read.
  */
 int ubifs_tnc_get_bu_keys(struct ubifs_info *c, struct bu_info *bu)
 {
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index fc2a4cc66d0..039a68bee29 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -426,9 +426,9 @@ struct ubifs_unclean_leb {
  * LEB properties flags.
  *
  * LPROPS_UNCAT: not categorized
- * LPROPS_DIRTY: dirty > 0, not index
+ * LPROPS_DIRTY: dirty > free, dirty >= @c->dead_wm, not index
  * LPROPS_DIRTY_IDX: dirty + free > @c->min_idx_node_sze and index
- * LPROPS_FREE: free > 0, not empty, not index
+ * LPROPS_FREE: free > 0, dirty < @c->dead_wm, not empty, not index
  * LPROPS_HEAP_CNT: number of heaps used for storing categorized LEBs
  * LPROPS_EMPTY: LEB is empty, not taken
  * LPROPS_FREEABLE: free + dirty == leb_size, not index, not taken
@@ -961,7 +961,6 @@ struct ubifs_debug_info;
  * @cs_lock: commit state lock
  * @cmt_wq: wait queue to sleep on if the log is full and a commit is running
  *
- * @fast_unmount: do not run journal commit before un-mounting
  * @big_lpt: flag that LPT is too big to write whole during commit
  * @no_chk_data_crc: do not check CRCs when reading data nodes (except during
  *                   recovery)
@@ -1202,7 +1201,6 @@ struct ubifs_info {
 	spinlock_t cs_lock;
 	wait_queue_head_t cmt_wq;
 
-	unsigned int fast_unmount:1;
 	unsigned int big_lpt:1;
 	unsigned int no_chk_data_crc:1;
 	unsigned int bulk_read:1;
@@ -1405,13 +1403,13 @@ extern struct list_head ubifs_infos;
 extern spinlock_t ubifs_infos_lock;
 extern atomic_long_t ubifs_clean_zn_cnt;
 extern struct kmem_cache *ubifs_inode_slab;
-extern struct super_operations ubifs_super_operations;
-extern struct address_space_operations ubifs_file_address_operations;
-extern struct file_operations ubifs_file_operations;
-extern struct inode_operations ubifs_file_inode_operations;
-extern struct file_operations ubifs_dir_operations;
-extern struct inode_operations ubifs_dir_inode_operations;
-extern struct inode_operations ubifs_symlink_inode_operations;
+extern const struct super_operations ubifs_super_operations;
+extern const struct address_space_operations ubifs_file_address_operations;
+extern const struct file_operations ubifs_file_operations;
+extern const struct inode_operations ubifs_file_inode_operations;
+extern const struct file_operations ubifs_dir_operations;
+extern const struct inode_operations ubifs_dir_inode_operations;
+extern const struct inode_operations ubifs_symlink_inode_operations;
 extern struct backing_dev_info ubifs_backing_dev_info;
 extern struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
 
@@ -1428,7 +1426,7 @@ int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
 int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum,
 		     int offs, int dtype);
 int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
-		     int offs, int quiet, int chk_crc);
+		     int offs, int quiet, int must_chk_crc);
 void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad);
 void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last);
 int ubifs_io_init(struct ubifs_info *c);
@@ -1495,6 +1493,7 @@ void ubifs_release_ino_dirty(struct ubifs_info *c, struct inode *inode,
 void ubifs_cancel_ino_op(struct ubifs_info *c, struct inode *inode,
 			 struct ubifs_budget_req *req);
 long long ubifs_get_free_space(struct ubifs_info *c);
+long long ubifs_get_free_space_nolock(struct ubifs_info *c);
 int ubifs_calc_min_idx_lebs(struct ubifs_info *c);
 void ubifs_convert_page_budget(struct ubifs_info *c);
 long long ubifs_reported_space(const struct ubifs_info *c, long long free);
@@ -1603,6 +1602,7 @@ void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum);
 int ubifs_orphan_start_commit(struct ubifs_info *c);
 int ubifs_orphan_end_commit(struct ubifs_info *c);
 int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only);
+int ubifs_clear_orphans(struct ubifs_info *c);
 
 /* lpt.c */
 int ubifs_calc_lpt_geom(struct ubifs_info *c);
@@ -1646,7 +1646,7 @@ const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
 					   const struct ubifs_lprops *lp,
 					   int free, int dirty, int flags,
 					   int idx_gc_cnt);
-void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *stats);
+void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst);
 void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
 		      int cat);
 void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
diff --git a/fs/xfs/linux-2.6/xfs_sync.c b/fs/xfs/linux-2.6/xfs_sync.c
index 2ed035354c2..a608e72fa40 100644
--- a/fs/xfs/linux-2.6/xfs_sync.c
+++ b/fs/xfs/linux-2.6/xfs_sync.c
@@ -371,7 +371,11 @@ xfs_quiesce_attr(
 	/* flush inodes and push all remaining buffers out to disk */
 	xfs_quiesce_fs(mp);
 
-	ASSERT_ALWAYS(atomic_read(&mp->m_active_trans) == 0);
+	/*
+	 * Just warn here till VFS can correctly support
+	 * read-only remount without racing.
+	 */
+	WARN_ON(atomic_read(&mp->m_active_trans) != 0);
 
 	/* Push the superblock and write an unmount record */
 	error = xfs_log_sbcount(mp, 1);
diff --git a/fs/xfs/xfs_dfrag.c b/fs/xfs/xfs_dfrag.c
index b4c1ee71349..f8278cfcc1d 100644
--- a/fs/xfs/xfs_dfrag.c
+++ b/fs/xfs/xfs_dfrag.c
@@ -55,17 +55,11 @@ xfs_swapext(
 	struct file	*file, *target_file;
 	int		error = 0;
 
-	sxp = kmem_alloc(sizeof(xfs_swapext_t), KM_MAYFAIL);
-	if (!sxp) {
-		error = XFS_ERROR(ENOMEM);
-		goto out;
-	}
-
 	/* Pull information for the target fd */
 	file = fget((int)sxp->sx_fdtarget);
 	if (!file) {
 		error = XFS_ERROR(EINVAL);
-		goto out_free_sxp;
+		goto out;
 	}
 
 	if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) {
@@ -109,8 +103,6 @@ xfs_swapext(
 	fput(target_file);
  out_put_file:
 	fput(file);
- out_free_sxp:
-	kmem_free(sxp);
  out:
 	return error;
 }
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 35cca98bd94..b1047de2fff 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -70,16 +70,21 @@ STATIC void	xlog_recover_check_summary(xlog_t *);
 xfs_buf_t *
 xlog_get_bp(
 	xlog_t		*log,
-	int		num_bblks)
+	int		nbblks)
 {
-	ASSERT(num_bblks > 0);
+	if (nbblks <= 0 || nbblks > log->l_logBBsize) {
+		xlog_warn("XFS: Invalid block length (0x%x) given for buffer", nbblks);
+		XFS_ERROR_REPORT("xlog_get_bp(1)",
+				 XFS_ERRLEVEL_HIGH, log->l_mp);
+		return NULL;
+	}
 
 	if (log->l_sectbb_log) {
-		if (num_bblks > 1)
-			num_bblks += XLOG_SECTOR_ROUNDUP_BBCOUNT(log, 1);
-		num_bblks = XLOG_SECTOR_ROUNDUP_BBCOUNT(log, num_bblks);
+		if (nbblks > 1)
+			nbblks += XLOG_SECTOR_ROUNDUP_BBCOUNT(log, 1);
+		nbblks = XLOG_SECTOR_ROUNDUP_BBCOUNT(log, nbblks);
 	}
-	return xfs_buf_get_noaddr(BBTOB(num_bblks), log->l_mp->m_logdev_targp);
+	return xfs_buf_get_noaddr(BBTOB(nbblks), log->l_mp->m_logdev_targp);
 }
 
 void
@@ -102,6 +107,13 @@ xlog_bread(
 {
 	int		error;
 
+	if (nbblks <= 0 || nbblks > log->l_logBBsize) {
+		xlog_warn("XFS: Invalid block length (0x%x) given for buffer", nbblks);
+		XFS_ERROR_REPORT("xlog_bread(1)",
+				 XFS_ERRLEVEL_HIGH, log->l_mp);
+		return EFSCORRUPTED;
+	}
+
 	if (log->l_sectbb_log) {
 		blk_no = XLOG_SECTOR_ROUNDDOWN_BLKNO(log, blk_no);
 		nbblks = XLOG_SECTOR_ROUNDUP_BBCOUNT(log, nbblks);
@@ -139,6 +151,13 @@ xlog_bwrite(
 {
 	int		error;
 
+	if (nbblks <= 0 || nbblks > log->l_logBBsize) {
+		xlog_warn("XFS: Invalid block length (0x%x) given for buffer", nbblks);
+		XFS_ERROR_REPORT("xlog_bwrite(1)",
+				 XFS_ERRLEVEL_HIGH, log->l_mp);
+		return EFSCORRUPTED;
+	}
+
 	if (log->l_sectbb_log) {
 		blk_no = XLOG_SECTOR_ROUNDDOWN_BLKNO(log, blk_no);
 		nbblks = XLOG_SECTOR_ROUNDUP_BBCOUNT(log, nbblks);