From bfab36e81611e60573b84eb4e4b4c8d8545b2320 Mon Sep 17 00:00:00 2001 From: Anton Altaparmakov Date: Fri, 12 Oct 2007 09:37:15 +0100 Subject: NTFS: Fix a mount time deadlock. Big thanks go to Mathias Kolehmainen for reporting the bug, providing debug output and testing the patches I sent him to get it working. The fix was to stop calling ntfs_attr_set() at mount time as that causes balance_dirty_pages_ratelimited() to be called which on systems with little memory actually tries to go and balance the dirty pages which tries to take the s_umount semaphore but because we are still in fill_super() across which the VFS holds s_umount for writing this results in a deadlock. We now do the dirty work by hand by submitting individual buffers. This has the annoying "feature" that mounting can take a few seconds if the journal is large as we have clear it all. One day someone should improve on this by deferring the journal clearing to a helper kernel thread so it can be done in the background but I don't have time for this at the moment and the current solution works fine so I am leaving it like this for now. Signed-off-by: Anton Altaparmakov Signed-off-by: Linus Torvalds --- fs/ntfs/ChangeLog | 12 +++++ fs/ntfs/Makefile | 2 +- fs/ntfs/aops.c | 22 ++++----- fs/ntfs/attrib.c | 8 ++- fs/ntfs/file.c | 36 +++++++------- fs/ntfs/inode.c | 3 -- fs/ntfs/logfile.c | 143 ++++++++++++++++++++++++++++++++++++++++++++++++------ fs/ntfs/runlist.c | 4 +- 8 files changed, 178 insertions(+), 52 deletions(-) (limited to 'fs/ntfs') diff --git a/fs/ntfs/ChangeLog b/fs/ntfs/ChangeLog index af4ef808fa9..345798ebd36 100644 --- a/fs/ntfs/ChangeLog +++ b/fs/ntfs/ChangeLog @@ -17,6 +17,18 @@ ToDo/Notes: happen is unclear however so it is worth waiting until someone hits the problem. +2.1.29 - Fix a deadlock at mount time. + + - During mount the VFS holds s_umount lock on the superblock. So when + we try to empty the journal $LogFile contents by calling + ntfs_attr_set() when the machine does not have much memory and the + journal is large ntfs_attr_set() results in the VM trying to balance + dirty pages which in turn tries to that the s_umount lock and thus we + get a deadlock. The solution is to not use ntfs_attr_set() and + instead do the zeroing by hand at the block level rather than page + cache level. + - Fix sparse warnings. + 2.1.28 - Fix a deadlock. - Fix deadlock in fs/ntfs/inode.c::ntfs_put_inode(). Thanks to Sergey diff --git a/fs/ntfs/Makefile b/fs/ntfs/Makefile index 82550838556..58b6be99254 100644 --- a/fs/ntfs/Makefile +++ b/fs/ntfs/Makefile @@ -6,7 +6,7 @@ ntfs-objs := aops.o attrib.o collate.o compress.o debug.o dir.o file.o \ index.o inode.o mft.o mst.o namei.o runlist.o super.o sysctl.o \ unistr.o upcase.o -EXTRA_CFLAGS = -DNTFS_VERSION=\"2.1.28\" +EXTRA_CFLAGS = -DNTFS_VERSION=\"2.1.29\" ifeq ($(CONFIG_NTFS_DEBUG),y) EXTRA_CFLAGS += -DDEBUG diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c index 6e5c2534f4b..cfdc7900d27 100644 --- a/fs/ntfs/aops.c +++ b/fs/ntfs/aops.c @@ -2,7 +2,7 @@ * aops.c - NTFS kernel address space operations and page cache handling. * Part of the Linux-NTFS project. * - * Copyright (c) 2001-2006 Anton Altaparmakov + * Copyright (c) 2001-2007 Anton Altaparmakov * Copyright (c) 2002 Richard Russon * * This program/include file is free software; you can redistribute it and/or @@ -396,7 +396,7 @@ static int ntfs_readpage(struct file *file, struct page *page) loff_t i_size; struct inode *vi; ntfs_inode *ni, *base_ni; - u8 *kaddr; + u8 *addr; ntfs_attr_search_ctx *ctx; MFT_RECORD *mrec; unsigned long flags; @@ -491,15 +491,15 @@ retry_readpage: /* Race with shrinking truncate. */ attr_len = i_size; } - kaddr = kmap_atomic(page, KM_USER0); + addr = kmap_atomic(page, KM_USER0); /* Copy the data to the page. */ - memcpy(kaddr, (u8*)ctx->attr + + memcpy(addr, (u8*)ctx->attr + le16_to_cpu(ctx->attr->data.resident.value_offset), attr_len); /* Zero the remainder of the page. */ - memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); + memset(addr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); flush_dcache_page(page); - kunmap_atomic(kaddr, KM_USER0); + kunmap_atomic(addr, KM_USER0); put_unm_err_out: ntfs_attr_put_search_ctx(ctx); unm_err_out: @@ -1344,7 +1344,7 @@ static int ntfs_writepage(struct page *page, struct writeback_control *wbc) loff_t i_size; struct inode *vi = page->mapping->host; ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi); - char *kaddr; + char *addr; ntfs_attr_search_ctx *ctx = NULL; MFT_RECORD *m = NULL; u32 attr_len; @@ -1484,14 +1484,14 @@ retry_writepage: /* Shrinking cannot fail. */ BUG_ON(err); } - kaddr = kmap_atomic(page, KM_USER0); + addr = kmap_atomic(page, KM_USER0); /* Copy the data from the page to the mft record. */ memcpy((u8*)ctx->attr + le16_to_cpu(ctx->attr->data.resident.value_offset), - kaddr, attr_len); + addr, attr_len); /* Zero out of bounds area in the page cache page. */ - memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); - kunmap_atomic(kaddr, KM_USER0); + memset(addr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); + kunmap_atomic(addr, KM_USER0); flush_dcache_page(page); flush_dcache_mft_record_page(ctx->ntfs_ino); /* We are done with the page. */ diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c index 1c08fefe487..92dabdcf2b8 100644 --- a/fs/ntfs/attrib.c +++ b/fs/ntfs/attrib.c @@ -1,7 +1,7 @@ /** * attrib.c - NTFS attribute operations. Part of the Linux-NTFS project. * - * Copyright (c) 2001-2006 Anton Altaparmakov + * Copyright (c) 2001-2007 Anton Altaparmakov * Copyright (c) 2002 Richard Russon * * This program/include file is free software; you can redistribute it and/or @@ -2500,7 +2500,7 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val) struct page *page; u8 *kaddr; pgoff_t idx, end; - unsigned int start_ofs, end_ofs, size; + unsigned start_ofs, end_ofs, size; ntfs_debug("Entering for ofs 0x%llx, cnt 0x%llx, val 0x%hx.", (long long)ofs, (long long)cnt, val); @@ -2548,6 +2548,8 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val) kunmap_atomic(kaddr, KM_USER0); set_page_dirty(page); page_cache_release(page); + balance_dirty_pages_ratelimited(mapping); + cond_resched(); if (idx == end) goto done; idx++; @@ -2604,6 +2606,8 @@ int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val) kunmap_atomic(kaddr, KM_USER0); set_page_dirty(page); page_cache_release(page); + balance_dirty_pages_ratelimited(mapping); + cond_resched(); } done: ntfs_debug("Done."); diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c index ffcc504a166..c814204d4ea 100644 --- a/fs/ntfs/file.c +++ b/fs/ntfs/file.c @@ -1,7 +1,7 @@ /* * file.c - NTFS kernel file operations. Part of the Linux-NTFS project. * - * Copyright (c) 2001-2006 Anton Altaparmakov + * Copyright (c) 2001-2007 Anton Altaparmakov * * This program/include file is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as published @@ -26,7 +26,6 @@ #include #include #include -#include #include #include @@ -362,7 +361,7 @@ static inline void ntfs_fault_in_pages_readable(const char __user *uaddr, volatile char c; /* Set @end to the first byte outside the last page we care about. */ - end = (const char __user*)PAGE_ALIGN((ptrdiff_t __user)uaddr + bytes); + end = (const char __user*)PAGE_ALIGN((unsigned long)uaddr + bytes); while (!__get_user(c, uaddr) && (uaddr += PAGE_SIZE, uaddr < end)) ; @@ -532,7 +531,8 @@ static int ntfs_prepare_pages_for_non_resident_write(struct page **pages, blocksize_bits = vol->sb->s_blocksize_bits; u = 0; do { - struct page *page = pages[u]; + page = pages[u]; + BUG_ON(!page); /* * create_empty_buffers() will create uptodate/dirty buffers if * the page is uptodate/dirty. @@ -1291,7 +1291,7 @@ static inline size_t ntfs_copy_from_user(struct page **pages, size_t bytes) { struct page **last_page = pages + nr_pages; - char *kaddr; + char *addr; size_t total = 0; unsigned len; int left; @@ -1300,13 +1300,13 @@ static inline size_t ntfs_copy_from_user(struct page **pages, len = PAGE_CACHE_SIZE - ofs; if (len > bytes) len = bytes; - kaddr = kmap_atomic(*pages, KM_USER0); - left = __copy_from_user_inatomic(kaddr + ofs, buf, len); - kunmap_atomic(kaddr, KM_USER0); + addr = kmap_atomic(*pages, KM_USER0); + left = __copy_from_user_inatomic(addr + ofs, buf, len); + kunmap_atomic(addr, KM_USER0); if (unlikely(left)) { /* Do it the slow way. */ - kaddr = kmap(*pages); - left = __copy_from_user(kaddr + ofs, buf, len); + addr = kmap(*pages); + left = __copy_from_user(addr + ofs, buf, len); kunmap(*pages); if (unlikely(left)) goto err_out; @@ -1408,26 +1408,26 @@ static inline size_t ntfs_copy_from_user_iovec(struct page **pages, size_t *iov_ofs, size_t bytes) { struct page **last_page = pages + nr_pages; - char *kaddr; + char *addr; size_t copied, len, total = 0; do { len = PAGE_CACHE_SIZE - ofs; if (len > bytes) len = bytes; - kaddr = kmap_atomic(*pages, KM_USER0); - copied = __ntfs_copy_from_user_iovec_inatomic(kaddr + ofs, + addr = kmap_atomic(*pages, KM_USER0); + copied = __ntfs_copy_from_user_iovec_inatomic(addr + ofs, *iov, *iov_ofs, len); - kunmap_atomic(kaddr, KM_USER0); + kunmap_atomic(addr, KM_USER0); if (unlikely(copied != len)) { /* Do it the slow way. */ - kaddr = kmap(*pages); - copied = __ntfs_copy_from_user_iovec_inatomic(kaddr + ofs, + addr = kmap(*pages); + copied = __ntfs_copy_from_user_iovec_inatomic(addr + ofs, *iov, *iov_ofs, len); /* * Zero the rest of the target like __copy_from_user(). */ - memset(kaddr + ofs + copied, 0, len - copied); + memset(addr + ofs + copied, 0, len - copied); kunmap(*pages); if (unlikely(copied != len)) goto err_out; @@ -1735,8 +1735,6 @@ static int ntfs_commit_pages_after_write(struct page **pages, read_unlock_irqrestore(&ni->size_lock, flags); BUG_ON(initialized_size != i_size); if (end > initialized_size) { - unsigned long flags; - write_lock_irqsave(&ni->size_lock, flags); ni->initialized_size = end; i_size_write(vi, end); diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c index b532a730cec..e9da092e277 100644 --- a/fs/ntfs/inode.c +++ b/fs/ntfs/inode.c @@ -34,7 +34,6 @@ #include "dir.h" #include "debug.h" #include "inode.h" -#include "attrib.h" #include "lcnalloc.h" #include "malloc.h" #include "mft.h" @@ -2500,8 +2499,6 @@ retry_truncate: /* Resize the attribute record to best fit the new attribute size. */ if (new_size < vol->mft_record_size && !ntfs_resident_attr_value_resize(m, a, new_size)) { - unsigned long flags; - /* The resize succeeded! */ flush_dcache_mft_record_page(ctx->ntfs_ino); mark_mft_record_dirty(ctx->ntfs_ino); diff --git a/fs/ntfs/logfile.c b/fs/ntfs/logfile.c index acfed325f4e..d7932e95b1f 100644 --- a/fs/ntfs/logfile.c +++ b/fs/ntfs/logfile.c @@ -1,7 +1,7 @@ /* * logfile.c - NTFS kernel journal handling. Part of the Linux-NTFS project. * - * Copyright (c) 2002-2005 Anton Altaparmakov + * Copyright (c) 2002-2007 Anton Altaparmakov * * This program/include file is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as published @@ -724,24 +724,139 @@ bool ntfs_is_logfile_clean(struct inode *log_vi, const RESTART_PAGE_HEADER *rp) */ bool ntfs_empty_logfile(struct inode *log_vi) { - ntfs_volume *vol = NTFS_SB(log_vi->i_sb); + VCN vcn, end_vcn; + ntfs_inode *log_ni = NTFS_I(log_vi); + ntfs_volume *vol = log_ni->vol; + struct super_block *sb = vol->sb; + runlist_element *rl; + unsigned long flags; + unsigned block_size, block_size_bits; + int err; + bool should_wait = true; ntfs_debug("Entering."); - if (!NVolLogFileEmpty(vol)) { - int err; - - err = ntfs_attr_set(NTFS_I(log_vi), 0, i_size_read(log_vi), - 0xff); - if (unlikely(err)) { - ntfs_error(vol->sb, "Failed to fill $LogFile with " - "0xff bytes (error code %i).", err); - return false; - } - /* Set the flag so we do not have to do it again on remount. */ - NVolSetLogFileEmpty(vol); + if (NVolLogFileEmpty(vol)) { + ntfs_debug("Done."); + return true; } + /* + * We cannot use ntfs_attr_set() because we may be still in the middle + * of a mount operation. Thus we do the emptying by hand by first + * zapping the page cache pages for the $LogFile/$DATA attribute and + * then emptying each of the buffers in each of the clusters specified + * by the runlist by hand. + */ + block_size = sb->s_blocksize; + block_size_bits = sb->s_blocksize_bits; + vcn = 0; + read_lock_irqsave(&log_ni->size_lock, flags); + end_vcn = (log_ni->initialized_size + vol->cluster_size_mask) >> + vol->cluster_size_bits; + read_unlock_irqrestore(&log_ni->size_lock, flags); + truncate_inode_pages(log_vi->i_mapping, 0); + down_write(&log_ni->runlist.lock); + rl = log_ni->runlist.rl; + if (unlikely(!rl || vcn < rl->vcn || !rl->length)) { +map_vcn: + err = ntfs_map_runlist_nolock(log_ni, vcn, NULL); + if (err) { + ntfs_error(sb, "Failed to map runlist fragment (error " + "%d).", -err); + goto err; + } + rl = log_ni->runlist.rl; + BUG_ON(!rl || vcn < rl->vcn || !rl->length); + } + /* Seek to the runlist element containing @vcn. */ + while (rl->length && vcn >= rl[1].vcn) + rl++; + do { + LCN lcn; + sector_t block, end_block; + s64 len; + + /* + * If this run is not mapped map it now and start again as the + * runlist will have been updated. + */ + lcn = rl->lcn; + if (unlikely(lcn == LCN_RL_NOT_MAPPED)) { + vcn = rl->vcn; + goto map_vcn; + } + /* If this run is not valid abort with an error. */ + if (unlikely(!rl->length || lcn < LCN_HOLE)) + goto rl_err; + /* Skip holes. */ + if (lcn == LCN_HOLE) + continue; + block = lcn << vol->cluster_size_bits >> block_size_bits; + len = rl->length; + if (rl[1].vcn > end_vcn) + len = end_vcn - rl->vcn; + end_block = (lcn + len) << vol->cluster_size_bits >> + block_size_bits; + /* Iterate over the blocks in the run and empty them. */ + do { + struct buffer_head *bh; + + /* Obtain the buffer, possibly not uptodate. */ + bh = sb_getblk(sb, block); + BUG_ON(!bh); + /* Setup buffer i/o submission. */ + lock_buffer(bh); + bh->b_end_io = end_buffer_write_sync; + get_bh(bh); + /* Set the entire contents of the buffer to 0xff. */ + memset(bh->b_data, -1, block_size); + if (!buffer_uptodate(bh)) + set_buffer_uptodate(bh); + if (buffer_dirty(bh)) + clear_buffer_dirty(bh); + /* + * Submit the buffer and wait for i/o to complete but + * only for the first buffer so we do not miss really + * serious i/o errors. Once the first buffer has + * completed ignore errors afterwards as we can assume + * that if one buffer worked all of them will work. + */ + submit_bh(WRITE, bh); + if (should_wait) { + should_wait = false; + wait_on_buffer(bh); + if (unlikely(!buffer_uptodate(bh))) + goto io_err; + } + brelse(bh); + } while (++block < end_block); + } while ((++rl)->vcn < end_vcn); + up_write(&log_ni->runlist.lock); + /* + * Zap the pages again just in case any got instantiated whilst we were + * emptying the blocks by hand. FIXME: We may not have completed + * writing to all the buffer heads yet so this may happen too early. + * We really should use a kernel thread to do the emptying + * asynchronously and then we can also set the volume dirty and output + * an error message if emptying should fail. + */ + truncate_inode_pages(log_vi->i_mapping, 0); + /* Set the flag so we do not have to do it again on remount. */ + NVolSetLogFileEmpty(vol); ntfs_debug("Done."); return true; +io_err: + ntfs_error(sb, "Failed to write buffer. Unmount and run chkdsk."); + goto dirty_err; +rl_err: + ntfs_error(sb, "Runlist is corrupt. Unmount and run chkdsk."); +dirty_err: + NVolSetErrors(vol); + err = -EIO; +err: + up_write(&log_ni->runlist.lock); + ntfs_error(sb, "Failed to fill $LogFile with 0xff bytes (error %d).", + -err); + return false; } #endif /* NTFS_RW */ diff --git a/fs/ntfs/runlist.c b/fs/ntfs/runlist.c index 9afd72c7ad0..56a9a6d25a2 100644 --- a/fs/ntfs/runlist.c +++ b/fs/ntfs/runlist.c @@ -1,7 +1,7 @@ /** * runlist.c - NTFS runlist handling code. Part of the Linux-NTFS project. * - * Copyright (c) 2001-2005 Anton Altaparmakov + * Copyright (c) 2001-2007 Anton Altaparmakov * Copyright (c) 2002-2005 Richard Russon * * This program/include file is free software; you can redistribute it and/or @@ -1714,7 +1714,7 @@ extend_hole: sizeof(*rl)); /* Adjust the beginning of the tail if necessary. */ if (end > rl->vcn) { - s64 delta = end - rl->vcn; + delta = end - rl->vcn; rl->vcn = end; rl->length -= delta; /* Only adjust the lcn if it is real. */ -- cgit v1.2.3