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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 13:40:20 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 13:40:20 -0700
commitdc690d8ef842b464f1c429a376ca16cb8dbee6ae (patch)
tree77955849af5a15755f5e55e24ae4b9c520583a72 /fs
parent57399ec9077a4b962b81037aaa279fab52f5e989 (diff)
parent91a6902958f052358899f58683d44e36228d85c2 (diff)
Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (61 commits) sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sysfs binary attributes sysfs: make directory dentries and inodes reclaimable sysfs: implement sysfs_get_dentry() sysfs: move sysfs_drop_dentry() to dir.c and make it static sysfs: restructure add/remove paths and fix inode update sysfs: use sysfs_mutex to protect the sysfs_dirent tree sysfs: consolidate sysfs spinlocks sysfs: make kobj point to sysfs_dirent instead of dentry sysfs: implement sysfs_find_dirent() and sysfs_get_dirent() sysfs: implement SYSFS_FLAG_REMOVED flag sysfs: rename sysfs_dirent->s_type to s_flags and make room for flags sysfs: make sysfs_drop_dentry() access inodes using ilookup() sysfs: Fix oops in sysfs_drop_dentry on x86_64 sysfs: use singly-linked list for sysfs_dirent tree sysfs: slim down sysfs_dirent->s_active sysfs: move s_active functions to fs/sysfs/dir.c sysfs: fix root sysfs_dirent -> root dentry association sysfs: use iget_locked() instead of new_inode() sysfs: reorganize sysfs_new_indoe() and sysfs_create() sysfs: fix parent refcounting during rename and move ...
Diffstat (limited to 'fs')
-rw-r--r--fs/debugfs/inode.c63
-rw-r--r--fs/ecryptfs/main.c2
-rw-r--r--fs/ocfs2/cluster/masklog.c1
-rw-r--r--fs/partitions/check.c1
-rw-r--r--fs/sysfs/bin.c195
-rw-r--r--fs/sysfs/dir.c1297
-rw-r--r--fs/sysfs/file.c379
-rw-r--r--fs/sysfs/group.c55
-rw-r--r--fs/sysfs/inode.c221
-rw-r--r--fs/sysfs/mount.c36
-rw-r--r--fs/sysfs/symlink.c150
-rw-r--r--fs/sysfs/sysfs.h169
12 files changed, 1563 insertions, 1006 deletions
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index ec8896b264d..1d533a2ec3a 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -368,6 +368,69 @@ void debugfs_remove(struct dentry *dentry)
}
EXPORT_SYMBOL_GPL(debugfs_remove);
+/**
+ * debugfs_rename - rename a file/directory in the debugfs filesystem
+ * @old_dir: a pointer to the parent dentry for the renamed object. This
+ * should be a directory dentry.
+ * @old_dentry: dentry of an object to be renamed.
+ * @new_dir: a pointer to the parent dentry where the object should be
+ * moved. This should be a directory dentry.
+ * @new_name: a pointer to a string containing the target name.
+ *
+ * This function renames a file/directory in debugfs. The target must not
+ * exist for rename to succeed.
+ *
+ * This function will return a pointer to old_dentry (which is updated to
+ * reflect renaming) if it succeeds. If an error occurs, %NULL will be
+ * returned.
+ *
+ * If debugfs is not enabled in the kernel, the value -%ENODEV will be
+ * returned.
+ */
+struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
+ struct dentry *new_dir, const char *new_name)
+{
+ int error;
+ struct dentry *dentry = NULL, *trap;
+ const char *old_name;
+
+ trap = lock_rename(new_dir, old_dir);
+ /* Source or destination directories don't exist? */
+ if (!old_dir->d_inode || !new_dir->d_inode)
+ goto exit;
+ /* Source does not exist, cyclic rename, or mountpoint? */
+ if (!old_dentry->d_inode || old_dentry == trap ||
+ d_mountpoint(old_dentry))
+ goto exit;
+ dentry = lookup_one_len(new_name, new_dir, strlen(new_name));
+ /* Lookup failed, cyclic rename or target exists? */
+ if (IS_ERR(dentry) || dentry == trap || dentry->d_inode)
+ goto exit;
+
+ old_name = fsnotify_oldname_init(old_dentry->d_name.name);
+
+ error = simple_rename(old_dir->d_inode, old_dentry, new_dir->d_inode,
+ dentry);
+ if (error) {
+ fsnotify_oldname_free(old_name);
+ goto exit;
+ }
+ d_move(old_dentry, dentry);
+ fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name,
+ old_dentry->d_name.name, S_ISDIR(old_dentry->d_inode->i_mode),
+ NULL, old_dentry->d_inode);
+ fsnotify_oldname_free(old_name);
+ unlock_rename(new_dir, old_dir);
+ dput(dentry);
+ return old_dentry;
+exit:
+ if (dentry && !IS_ERR(dentry))
+ dput(dentry);
+ unlock_rename(new_dir, old_dir);
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(debugfs_rename);
+
static decl_subsys(debug, NULL, NULL);
static int __init debugfs_init(void)
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index 606128f5c92..02ca6f1e55d 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -840,8 +840,6 @@ static int __init ecryptfs_init(void)
goto out;
}
kobj_set_kset_s(&ecryptfs_subsys, fs_subsys);
- sysfs_attr_version.attr.owner = THIS_MODULE;
- sysfs_attr_version_str.attr.owner = THIS_MODULE;
rc = do_sysfs_registration();
if (rc) {
printk(KERN_ERR "sysfs registration failed\n");
diff --git a/fs/ocfs2/cluster/masklog.c b/fs/ocfs2/cluster/masklog.c
index 2b205f5d579..e9e042b93db 100644
--- a/fs/ocfs2/cluster/masklog.c
+++ b/fs/ocfs2/cluster/masklog.c
@@ -74,7 +74,6 @@ struct mlog_attribute {
#define define_mask(_name) { \
.attr = { \
.name = #_name, \
- .owner = THIS_MODULE, \
.mode = S_IRUGO | S_IWUSR, \
}, \
.mask = ML_##_name, \
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index 9a3a058f355..98e0b85a9bb 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -397,7 +397,6 @@ void add_partition(struct gendisk *disk, int part, sector_t start, sector_t len,
static struct attribute addpartattr = {
.name = "whole_disk",
.mode = S_IRUSR | S_IRGRP | S_IROTH,
- .owner = THIS_MODULE,
};
sysfs_create_file(&p->kobj, &addpartattr);
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index d3b9f5f07db..135353f8a29 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -20,29 +20,41 @@
#include "sysfs.h"
+struct bin_buffer {
+ struct mutex mutex;
+ void *buffer;
+ int mmapped;
+};
+
static int
fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
{
- struct bin_attribute * attr = to_bin_attr(dentry);
- struct kobject * kobj = to_kobj(dentry->d_parent);
+ struct sysfs_dirent *attr_sd = dentry->d_fsdata;
+ struct bin_attribute *attr = attr_sd->s_elem.bin_attr.bin_attr;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
+ int rc;
+
+ /* need attr_sd for attr, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
- if (!attr->read)
- return -EIO;
+ rc = -EIO;
+ if (attr->read)
+ rc = attr->read(kobj, attr, buffer, off, count);
- return attr->read(kobj, buffer, off, count);
+ sysfs_put_active_two(attr_sd);
+
+ return rc;
}
static ssize_t
-read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
+read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
{
- char *buffer = file->private_data;
+ struct bin_buffer *bb = file->private_data;
struct dentry *dentry = file->f_path.dentry;
int size = dentry->d_inode->i_size;
loff_t offs = *off;
- int ret;
-
- if (count > PAGE_SIZE)
- count = PAGE_SIZE;
+ int count = min_t(size_t, bytes, PAGE_SIZE);
if (size) {
if (offs > size)
@@ -51,43 +63,56 @@ read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
count = size - offs;
}
- ret = fill_read(dentry, buffer, offs, count);
- if (ret < 0)
- return ret;
- count = ret;
+ mutex_lock(&bb->mutex);
+
+ count = fill_read(dentry, bb->buffer, offs, count);
+ if (count < 0)
+ goto out_unlock;
- if (copy_to_user(userbuf, buffer, count))
- return -EFAULT;
+ if (copy_to_user(userbuf, bb->buffer, count)) {
+ count = -EFAULT;
+ goto out_unlock;
+ }
- pr_debug("offs = %lld, *off = %lld, count = %zd\n", offs, *off, count);
+ pr_debug("offs = %lld, *off = %lld, count = %d\n", offs, *off, count);
*off = offs + count;
+ out_unlock:
+ mutex_unlock(&bb->mutex);
return count;
}
static int
flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
{
- struct bin_attribute *attr = to_bin_attr(dentry);
- struct kobject *kobj = to_kobj(dentry->d_parent);
+ struct sysfs_dirent *attr_sd = dentry->d_fsdata;
+ struct bin_attribute *attr = attr_sd->s_elem.bin_attr.bin_attr;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
+ int rc;
+
+ /* need attr_sd for attr, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
+
+ rc = -EIO;
+ if (attr->write)
+ rc = attr->write(kobj, attr, buffer, offset, count);
- if (!attr->write)
- return -EIO;
+ sysfs_put_active_two(attr_sd);
- return attr->write(kobj, buffer, offset, count);
+ return rc;
}
-static ssize_t write(struct file * file, const char __user * userbuf,
- size_t count, loff_t * off)
+static ssize_t write(struct file *file, const char __user *userbuf,
+ size_t bytes, loff_t *off)
{
- char *buffer = file->private_data;
+ struct bin_buffer *bb = file->private_data;
struct dentry *dentry = file->f_path.dentry;
int size = dentry->d_inode->i_size;
loff_t offs = *off;
+ int count = min_t(size_t, bytes, PAGE_SIZE);
- if (count > PAGE_SIZE)
- count = PAGE_SIZE;
if (size) {
if (offs > size)
return 0;
@@ -95,72 +120,100 @@ static ssize_t write(struct file * file, const char __user * userbuf,
count = size - offs;
}
- if (copy_from_user(buffer, userbuf, count))
- return -EFAULT;
+ mutex_lock(&bb->mutex);
- count = flush_write(dentry, buffer, offs, count);
+ if (copy_from_user(bb->buffer, userbuf, count)) {
+ count = -EFAULT;
+ goto out_unlock;
+ }
+
+ count = flush_write(dentry, bb->buffer, offs, count);
if (count > 0)
*off = offs + count;
+
+ out_unlock:
+ mutex_unlock(&bb->mutex);
return count;
}
static int mmap(struct file *file, struct vm_area_struct *vma)
{
- struct dentry *dentry = file->f_path.dentry;
- struct bin_attribute *attr = to_bin_attr(dentry);
- struct kobject *kobj = to_kobj(dentry->d_parent);
+ struct bin_buffer *bb = file->private_data;
+ struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+ struct bin_attribute *attr = attr_sd->s_elem.bin_attr.bin_attr;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
+ int rc;
+
+ mutex_lock(&bb->mutex);
+
+ /* need attr_sd for attr, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
- if (!attr->mmap)
- return -EINVAL;
+ rc = -EINVAL;
+ if (attr->mmap)
+ rc = attr->mmap(kobj, attr, vma);
- return attr->mmap(kobj, attr, vma);
+ if (rc == 0 && !bb->mmapped)
+ bb->mmapped = 1;
+ else
+ sysfs_put_active_two(attr_sd);
+
+ mutex_unlock(&bb->mutex);
+
+ return rc;
}
static int open(struct inode * inode, struct file * file)
{
- struct kobject *kobj = sysfs_get_kobject(file->f_path.dentry->d_parent);
- struct bin_attribute * attr = to_bin_attr(file->f_path.dentry);
- int error = -EINVAL;
-
- if (!kobj || !attr)
- goto Done;
+ struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+ struct bin_attribute *attr = attr_sd->s_elem.bin_attr.bin_attr;
+ struct bin_buffer *bb = NULL;
+ int error;
- /* Grab the module reference for this attribute if we have one */
- error = -ENODEV;
- if (!try_module_get(attr->attr.owner))
- goto Done;
+ /* need attr_sd for attr */
+ if (!sysfs_get_active(attr_sd))
+ return -ENODEV;
error = -EACCES;
if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap))
- goto Error;
+ goto err_out;
if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap))
- goto Error;
+ goto err_out;
error = -ENOMEM;
- file->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (!file->private_data)
- goto Error;
-
- error = 0;
- goto Done;
-
- Error:
- module_put(attr->attr.owner);
- Done:
- if (error)
- kobject_put(kobj);
+ bb = kzalloc(sizeof(*bb), GFP_KERNEL);
+ if (!bb)
+ goto err_out;
+
+ bb->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!bb->buffer)
+ goto err_out;
+
+ mutex_init(&bb->mutex);
+ file->private_data = bb;
+
+ /* open succeeded, put active reference and pin attr_sd */
+ sysfs_put_active(attr_sd);
+ sysfs_get(attr_sd);
+ return 0;
+
+ err_out:
+ sysfs_put_active(attr_sd);
+ kfree(bb);
return error;
}
static int release(struct inode * inode, struct file * file)
{
- struct kobject * kobj = to_kobj(file->f_path.dentry->d_parent);
- struct bin_attribute * attr = to_bin_attr(file->f_path.dentry);
- u8 * buffer = file->private_data;
-
- kobject_put(kobj);
- module_put(attr->attr.owner);
- kfree(buffer);
+ struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+ struct bin_buffer *bb = file->private_data;
+
+ if (bb->mmapped)
+ sysfs_put_active_two(attr_sd);
+ sysfs_put(attr_sd);
+ kfree(bb->buffer);
+ kfree(bb);
return 0;
}
@@ -181,9 +234,9 @@ const struct file_operations bin_fops = {
int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
{
- BUG_ON(!kobj || !kobj->dentry || !attr);
+ BUG_ON(!kobj || !kobj->sd || !attr);
- return sysfs_add_file(kobj->dentry, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
+ return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
}
@@ -195,7 +248,7 @@ int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
void sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
{
- if (sysfs_hash_and_remove(kobj->dentry, attr->attr.name) < 0) {
+ if (sysfs_hash_and_remove(kobj->sd, attr->attr.name) < 0) {
printk(KERN_ERR "%s: "
"bad dentry or inode or no such file: \"%s\"\n",
__FUNCTION__, attr->attr.name);
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index c4342a01997..aee966c44aa 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -9,21 +9,337 @@
#include <linux/module.h>
#include <linux/kobject.h>
#include <linux/namei.h>
+#include <linux/idr.h>
+#include <linux/completion.h>
#include <asm/semaphore.h>
#include "sysfs.h"
-DECLARE_RWSEM(sysfs_rename_sem);
-spinlock_t sysfs_lock = SPIN_LOCK_UNLOCKED;
+DEFINE_MUTEX(sysfs_mutex);
+spinlock_t sysfs_assoc_lock = SPIN_LOCK_UNLOCKED;
+
+static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_IDA(sysfs_ino_ida);
+
+/**
+ * sysfs_link_sibling - link sysfs_dirent into sibling list
+ * @sd: sysfs_dirent of interest
+ *
+ * Link @sd into its sibling list which starts from
+ * sd->s_parent->s_children.
+ *
+ * Locking:
+ * mutex_lock(sysfs_mutex)
+ */
+void sysfs_link_sibling(struct sysfs_dirent *sd)
+{
+ struct sysfs_dirent *parent_sd = sd->s_parent;
+
+ BUG_ON(sd->s_sibling);
+ sd->s_sibling = parent_sd->s_children;
+ parent_sd->s_children = sd;
+}
+
+/**
+ * sysfs_unlink_sibling - unlink sysfs_dirent from sibling list
+ * @sd: sysfs_dirent of interest
+ *
+ * Unlink @sd from its sibling list which starts from
+ * sd->s_parent->s_children.
+ *
+ * Locking:
+ * mutex_lock(sysfs_mutex)
+ */
+void sysfs_unlink_sibling(struct sysfs_dirent *sd)
+{
+ struct sysfs_dirent **pos;
+
+ for (pos = &sd->s_parent->s_children; *pos; pos = &(*pos)->s_sibling) {
+ if (*pos == sd) {
+ *pos = sd->s_sibling;
+ sd->s_sibling = NULL;
+ break;
+ }
+ }
+}
+
+/**
+ * sysfs_get_dentry - get dentry for the given sysfs_dirent
+ * @sd: sysfs_dirent of interest
+ *
+ * Get dentry for @sd. Dentry is looked up if currently not
+ * present. This function climbs sysfs_dirent tree till it
+ * reaches a sysfs_dirent with valid dentry attached and descends
+ * down from there looking up dentry for each step.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep)
+ *
+ * RETURNS:
+ * Pointer to found dentry on success, ERR_PTR() value on error.
+ */
+struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd)
+{
+ struct sysfs_dirent *cur;
+ struct dentry *parent_dentry, *dentry;
+ int i, depth;
+
+ /* Find the first parent which has valid s_dentry and get the
+ * dentry.
+ */
+ mutex_lock(&sysfs_mutex);
+ restart0:
+ spin_lock(&sysfs_assoc_lock);
+ restart1:
+ spin_lock(&dcache_lock);
+
+ dentry = NULL;
+ depth = 0;
+ cur = sd;
+ while (!cur->s_dentry || !cur->s_dentry->d_inode) {
+ if (cur->s_flags & SYSFS_FLAG_REMOVED) {
+ dentry = ERR_PTR(-ENOENT);
+ depth = 0;
+ break;
+ }
+ cur = cur->s_parent;
+ depth++;
+ }
+ if (!IS_ERR(dentry))
+ dentry = dget_locked(cur->s_dentry);
+
+ spin_unlock(&dcache_lock);
+ spin_unlock(&sysfs_assoc_lock);
+
+ /* from the found dentry, look up depth times */
+ while (depth--) {
+ /* find and get depth'th ancestor */
+ for (cur = sd, i = 0; cur && i < depth; i++)
+ cur = cur->s_parent;
+
+ /* This can happen if tree structure was modified due
+ * to move/rename. Restart.
+ */
+ if (i != depth) {
+ dput(dentry);
+ goto restart0;
+ }
+
+ sysfs_get(cur);
+
+ mutex_unlock(&sysfs_mutex);
+
+ /* look it up */
+ parent_dentry = dentry;
+ dentry = lookup_one_len_kern(cur->s_name, parent_dentry,
+ strlen(cur->s_name));
+ dput(parent_dentry);
+
+ if (IS_ERR(dentry)) {
+ sysfs_put(cur);
+ return dentry;
+ }
+
+ mutex_lock(&sysfs_mutex);
+ spin_lock(&sysfs_assoc_lock);
+
+ /* This, again, can happen if tree structure has
+ * changed and we looked up the wrong thing. Restart.
+ */
+ if (cur->s_dentry != dentry) {
+ dput(dentry);
+ sysfs_put(cur);
+ goto restart1;
+ }
+
+ spin_unlock(&sysfs_assoc_lock);
+
+ sysfs_put(cur);
+ }
+
+ mutex_unlock(&sysfs_mutex);
+ return dentry;
+}
+
+/**
+ * sysfs_get_active - get an active reference to sysfs_dirent
+ * @sd: sysfs_dirent to get an active reference to
+ *
+ * Get an active reference of @sd. This function is noop if @sd
+ * is NULL.
+ *
+ * RETURNS:
+ * Pointer to @sd on success, NULL on failure.
+ */
+struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd)
+{
+ if (unlikely(!sd))
+ return NULL;
+
+ while (1) {
+ int v, t;
+
+ v = atomic_read(&sd->s_active);
+ if (unlikely(v < 0))
+ return NULL;
+
+ t = atomic_cmpxchg(&sd->s_active, v, v + 1);
+ if (likely(t == v))
+ return sd;
+ if (t < 0)
+ return NULL;
+
+ cpu_relax();
+ }
+}
+
+/**
+ * sysfs_put_active - put an active reference to sysfs_dirent
+ * @sd: sysfs_dirent to put an active reference to
+ *
+ * Put an active reference to @sd. This function is noop if @sd
+ * is NULL.
+ */
+void sysfs_put_active(struct sysfs_dirent *sd)
+{
+ struct completion *cmpl;
+ int v;
+
+ if (unlikely(!sd))
+ return;
+
+ v = atomic_dec_return(&sd->s_active);
+ if (likely(v != SD_DEACTIVATED_BIAS))
+ return;
+
+ /* atomic_dec_return() is a mb(), we'll always see the updated
+ * sd->s_sibling.
+ */
+ cmpl = (void *)sd->s_sibling;
+ complete(cmpl);
+}
+
+/**
+ * sysfs_get_active_two - get active references to sysfs_dirent and parent
+ * @sd: sysfs_dirent of interest
+ *
+ * Get active reference to @sd and its parent. Parent's active
+ * reference is grabbed first. This function is noop if @sd is
+ * NULL.
+ *
+ * RETURNS:
+ * Pointer to @sd on success, NULL on failure.
+ */
+struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd)
+{
+ if (sd) {
+ if (sd->s_parent && unlikely(!sysfs_get_active(sd->s_parent)))
+ return NULL;
+ if (unlikely(!sysfs_get_active(sd))) {
+ sysfs_put_active(sd->s_parent);
+ return NULL;
+ }
+ }
+ return sd;
+}
+
+/**
+ * sysfs_put_active_two - put active references to sysfs_dirent and parent
+ * @sd: sysfs_dirent of interest
+ *
+ * Put active references to @sd and its parent. This function is
+ * noop if @sd is NULL.
+ */
+void sysfs_put_active_two(struct sysfs_dirent *sd)
+{
+ if (sd) {
+ sysfs_put_active(sd);
+ sysfs_put_active(sd->s_parent);
+ }
+}
+
+/**
+ * sysfs_deactivate - deactivate sysfs_dirent
+ * @sd: sysfs_dirent to deactivate
+ *
+ * Deny new active references and drain existing ones.
+ */
+static void sysfs_deactivate(struct sysfs_dirent *sd)
+{
+ DECLARE_COMPLETION_ONSTACK(wait);
+ int v;
+
+ BUG_ON(sd->s_sibling || !(sd->s_flags & SYSFS_FLAG_REMOVED));
+ sd->s_sibling = (void *)&wait;
+
+ /* atomic_add_return() is a mb(), put_active() will always see
+ * the updated sd->s_sibling.
+ */
+ v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active);
+
+ if (v != SD_DEACTIVATED_BIAS)
+ wait_for_completion(&wait);
+
+ sd->s_sibling = NULL;
+}
+
+static int sysfs_alloc_ino(ino_t *pino)
+{
+ int ino, rc;
+
+ retry:
+ spin_lock(&sysfs_ino_lock);
+ rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino);
+ spin_unlock(&sysfs_ino_lock);
+
+ if (rc == -EAGAIN) {
+ if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL))
+ goto retry;
+ rc = -ENOMEM;
+ }
+
+ *pino = ino;
+ return rc;
+}
+
+static void sysfs_free_ino(ino_t ino)
+{
+ spin_lock(&sysfs_ino_lock);
+ ida_remove(&sysfs_ino_ida, ino);
+ spin_unlock(&sysfs_ino_lock);
+}
+
+void release_sysfs_dirent(struct sysfs_dirent * sd)
+{
+ struct sysfs_dirent *parent_sd;
+
+ repeat:
+ /* Moving/renaming is always done while holding reference.
+ * sd->s_parent won't change beneath us.
+ */
+ parent_sd = sd->s_parent;
+
+ if (sysfs_type(sd) == SYSFS_KOBJ_LINK)
+ sysfs_put(sd->s_elem.symlink.target_sd);
+ if (sysfs_type(sd) & SYSFS_COPY_NAME)
+ kfree(sd->s_name);
+ kfree(sd->s_iattr);
+ sysfs_free_ino(sd->s_ino);
+ kmem_cache_free(sysfs_dir_cachep, sd);
+
+ sd = parent_sd;
+ if (sd && atomic_dec_and_test(&sd->s_count))
+ goto repeat;
+}
static void sysfs_d_iput(struct dentry * dentry, struct inode * inode)
{
struct sysfs_dirent * sd = dentry->d_fsdata;
if (sd) {
- /* sd->s_dentry is protected with sysfs_lock. This
- * allows sysfs_drop_dentry() to dereference it.
+ /* sd->s_dentry is protected with sysfs_assoc_lock.
+ * This allows sysfs_drop_dentry() to dereference it.
*/
- spin_lock(&sysfs_lock);
+ spin_lock(&sysfs_assoc_lock);
/* The dentry might have been deleted or another
* lookup could have happened updating sd->s_dentry to
@@ -32,7 +348,7 @@ static void sysfs_d_iput(struct dentry * dentry, struct inode * inode)
*/
if (sd->s_dentry == dentry)
sd->s_dentry = NULL;
- spin_unlock(&sysfs_lock);
+ spin_unlock(&sysfs_assoc_lock);
sysfs_put(sd);
}
iput(inode);
@@ -42,260 +358,402 @@ static struct dentry_operations sysfs_dentry_ops = {
.d_iput = sysfs_d_iput,
};
-static unsigned int sysfs_inode_counter;
-ino_t sysfs_get_inum(void)
+struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type)
{
- if (unlikely(sysfs_inode_counter < 3))
- sysfs_inode_counter = 3;
- return sysfs_inode_counter++;
-}
+ char *dup_name = NULL;
+ struct sysfs_dirent *sd = NULL;
-/*
- * Allocates a new sysfs_dirent and links it to the parent sysfs_dirent
- */
-static struct sysfs_dirent * __sysfs_new_dirent(void * element)
-{
- struct sysfs_dirent * sd;
+ if (type & SYSFS_COPY_NAME) {
+ name = dup_name = kstrdup(name, GFP_KERNEL);
+ if (!name)
+ goto err_out;
+ }
sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL);
if (!sd)
- return NULL;
+ goto err_out;
+
+ if (sysfs_alloc_ino(&sd->s_ino))
+ goto err_out;
- sd->s_ino = sysfs_get_inum();
atomic_set(&sd->s_count, 1);
+ atomic_set(&sd->s_active, 0);
atomic_set(&sd->s_event, 1);
- INIT_LIST_HEAD(&sd->s_children);
- INIT_LIST_HEAD(&sd->s_sibling);
- sd->s_element = element;
+
+ sd->s_name = name;
+ sd->s_mode = mode;
+ sd->s_flags = type;
return sd;
+
+ err_out:
+ kfree(dup_name);
+ kmem_cache_free(sysfs_dir_cachep, sd);
+ return NULL;
}
-static void __sysfs_list_dirent(struct sysfs_dirent *parent_sd,
- struct sysfs_dirent *sd)
+/**
+ * sysfs_attach_dentry - associate sysfs_dirent with dentry
+ * @sd: target sysfs_dirent
+ * @dentry: dentry to associate
+ *
+ * Associate @sd with @dentry. This is protected by
+ * sysfs_assoc_lock to avoid race with sysfs_d_iput().
+ *
+ * LOCKING:
+ * mutex_lock(sysfs_mutex)
+ */
+static void sysfs_attach_dentry(struct sysfs_dirent *sd, struct dentry *dentry)
{
- if (sd)
- list_add(&sd->s_sibling, &parent_sd->s_children);
+ dentry->d_op = &sysfs_dentry_ops;
+ dentry->d_fsdata = sysfs_get(sd);
+
+ /* protect sd->s_dentry against sysfs_d_iput */
+ spin_lock(&sysfs_assoc_lock);
+ sd->s_dentry = dentry;
+ spin_unlock(&sysfs_assoc_lock);
+
+ d_rehash(dentry);
}
-static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent *parent_sd,
- void * element)
+static int sysfs_ilookup_test(struct inode *inode, void *arg)
{
- struct sysfs_dirent *sd;
- sd = __sysfs_new_dirent(element);
- __sysfs_list_dirent(parent_sd, sd);
- return sd;
+ struct sysfs_dirent *sd = arg;
+ return inode->i_ino == sd->s_ino;
}
-/*
+/**
+ * sysfs_addrm_start - prepare for sysfs_dirent add/remove
+ * @acxt: pointer to sysfs_addrm_cxt to be used
+ * @parent_sd: parent sysfs_dirent
*
- * Return -EEXIST if there is already a sysfs element with the same name for
- * the same parent.
+ * This function is called when the caller is about to add or
+ * remove sysfs_dirent under @parent_sd. This function acquires
+ * sysfs_mutex, grabs inode for @parent_sd if available and lock
+ * i_mutex of it. @acxt is used to keep and pass context to
+ * other addrm functions.
*
- * called with parent inode's i_mutex held
+ * LOCKING:
+ * Kernel thread context (may sleep). sysfs_mutex is locked on
+ * return. i_mutex of parent inode is locked on return if
+ * available.
*/
-int sysfs_dirent_exist(struct sysfs_dirent *parent_sd,
- const unsigned char *new)
+void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
+ struct sysfs_dirent *parent_sd)
{
- struct sysfs_dirent * sd;
+ struct inode *inode;
- list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
- if (sd->s_element) {
- const unsigned char *existing = sysfs_get_name(sd);
- if (strcmp(existing, new))
- continue;
- else
- return -EEXIST;
- }
- }
+ memset(acxt, 0, sizeof(*acxt));
+ acxt->parent_sd = parent_sd;
- return 0;
+ /* Lookup parent inode. inode initialization and I_NEW
+ * clearing are protected by sysfs_mutex. By grabbing it and
+ * looking up with _nowait variant, inode state can be
+ * determined reliably.
+ */
+ mutex_lock(&sysfs_mutex);
+
+ inode = ilookup5_nowait(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test,
+ parent_sd);
+
+ if (inode && !(inode->i_state & I_NEW)) {
+ /* parent inode available */
+ acxt->parent_inode = inode;
+
+ /* sysfs_mutex is below i_mutex in lock hierarchy.
+ * First, trylock i_mutex. If fails, unlock
+ * sysfs_mutex and lock them in order.
+ */
+ if (!mutex_trylock(&inode->i_mutex)) {
+ mutex_unlock(&sysfs_mutex);
+ mutex_lock(&inode->i_mutex);
+ mutex_lock(&sysfs_mutex);
+ }
+ } else
+ iput(inode);
}
+/**
+ * sysfs_add_one - add sysfs_dirent to parent
+ * @acxt: addrm context to use
+ * @sd: sysfs_dirent to be added
+ *
+ * Get @acxt->parent_sd and set sd->s_parent to it and increment
+ * nlink of parent inode if @sd is a directory. @sd is NOT
+ * linked into the children list of the parent. The caller
+ * should invoke sysfs_link_sibling() after this function
+ * completes if @sd needs to be on the children list.
+ *
+ * This function should be called between calls to
+ * sysfs_addrm_start() and sysfs_addrm_finish() and should be
+ * passed the same @acxt as passed to sysfs_addrm_start().
+ *
+ * LOCKING:
+ * Determined by sysfs_addrm_start().
+ */
+void sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
+{
+ sd->s_parent = sysfs_get(acxt->parent_sd);
+
+ if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode)
+ inc_nlink(acxt->parent_inode);
+
+ acxt->cnt++;
+}
-static struct sysfs_dirent *
-__sysfs_make_dirent(struct dentry *dentry, void *element, mode_t mode, int type)
+/**
+ * sysfs_remove_one - remove sysfs_dirent from parent
+ * @acxt: addrm context to use
+ * @sd: sysfs_dirent to be added
+ *
+ * Mark @sd removed and drop nlink of parent inode if @sd is a
+ * directory. @sd is NOT unlinked from the children list of the
+ * parent. The caller is repsonsible for removing @sd from the
+ * children list before calling this function.
+ *
+ * This function should be called between calls to
+ * sysfs_addrm_start() and sysfs_addrm_finish() and should be
+ * passed the same @acxt as passed to sysfs_addrm_start().
+ *
+ * LOCKING:
+ * Determined by sysfs_addrm_start().
+ */
+void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
{
- struct sysfs_dirent * sd;
+ BUG_ON(sd->s_sibling || (sd->s_flags & SYSFS_FLAG_REMOVED));
- sd = __sysfs_new_dirent(element);
- if (!sd)
- goto out;
+ sd->s_flags |= SYSFS_FLAG_REMOVED;
+ sd->s_sibling = acxt->removed;
+ acxt->removed = sd;
- sd->s_mode = mode;
- sd->s_type = type;
- sd->s_dentry = dentry;
- if (dentry) {
- dentry->d_fsdata = sysfs_get(sd);
- dentry->d_op = &sysfs_dentry_ops;
- }
+ if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode)
+ drop_nlink(acxt->parent_inode);
-out:
- return sd;
+ acxt->cnt++;
}
-int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry,
- void * element, umode_t mode, int type)
+/**
+ * sysfs_drop_dentry - drop dentry for the specified sysfs_dirent
+ * @sd: target sysfs_dirent
+ *
+ * Drop dentry for @sd. @sd must have been unlinked from its
+ * parent on entry to this function such that it can't be looked
+ * up anymore.
+ *
+ * @sd->s_dentry which is protected with sysfs_assoc_lock points
+ * to the currently associated dentry but we're not holding a
+ * reference to it and racing with dput(). Grab dcache_lock and
+ * verify dentry before dropping it. If @sd->s_dentry is NULL or
+ * dput() beats us, no need to bother.
+ */
+static void sysfs_drop_dentry(struct sysfs_dirent *sd)
{
- struct sysfs_dirent *sd;
+ struct dentry *dentry = NULL;
+ struct inode *inode;
+
+ /* We're not holding a reference to ->s_dentry dentry but the
+ * field will stay valid as long as sysfs_assoc_lock is held.
+ */
+ spin_lock(&sysfs_assoc_lock);
+ spin_lock(&dcache_lock);
+
+ /* drop dentry if it's there and dput() didn't kill it yet */
+ if (sd->s_dentry && sd->s_dentry->d_inode) {
+ dentry = dget_locked(sd->s_dentry);
+ spin_lock(&dentry->d_lock);
+ __d_drop(dentry);
+ spin_unlock(&dentry->d_lock);
+ }
- sd = __sysfs_make_dirent(dentry, element, mode, type);
- __sysfs_list_dirent(parent_sd, sd);
+ spin_unlock(&dcache_lock);
+ spin_unlock(&sysfs_assoc_lock);
- return sd ? 0 : -ENOMEM;
+ /* dentries for shadowed inodes are pinned, unpin */
+ if (dentry && sysfs_is_shadowed_inode(dentry->d_inode))
+ dput(dentry);
+ dput(dentry);
+
+ /* adjust nlink and update timestamp */
+ inode = ilookup(sysfs_sb, sd->s_ino);
+ if (inode) {
+ mutex_lock(&inode->i_mutex);
+
+ inode->i_ctime = CURRENT_TIME;
+ drop_nlink(inode);
+ if (sysfs_type(sd) == SYSFS_DIR)
+ drop_nlink(inode);
+
+ mutex_unlock(&inode->i_mutex);
+ iput(inode);
+ }
}
-static int init_dir(struct inode * inode)
+/**
+ * sysfs_addrm_finish - finish up sysfs_dirent add/remove
+ * @acxt: addrm context to finish up
+ *
+ * Finish up sysfs_dirent add/remove. Resources acquired by
+ * sysfs_addrm_start() are released and removed sysfs_dirents are
+ * cleaned up. Timestamps on the parent inode are updated.
+ *
+ * LOCKING:
+ * All mutexes acquired by sysfs_addrm_start() are released.
+ *
+ * RETURNS:
+ * Number of added/removed sysfs_dirents since sysfs_addrm_start().
+ */
+int sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt)
{
- inode->i_op = &sysfs_dir_inode_operations;
- inode->i_fop = &sysfs_dir_operations;
+ /* release resources acquired by sysfs_addrm_start() */
+ mutex_unlock(&sysfs_mutex);
+ if (acxt->parent_inode) {
+ struct inode *inode = acxt->parent_inode;
- /* directory inodes start off with i_nlink == 2 (for "." entry) */
- inc_nlink(inode);
- return 0;
+ /* if added/removed, update timestamps on the parent */
+ if (acxt->cnt)
+ inode->i_ctime = inode->i_mtime = CURRENT_TIME;
+
+ mutex_unlock(&inode->i_mutex);
+ iput(inode);
+ }
+
+ /* kill removed sysfs_dirents */
+ while (acxt->removed) {
+ struct sysfs_dirent *sd = acxt->removed;
+
+ acxt->removed = sd->s_sibling;
+ sd->s_sibling = NULL;
+
+ sysfs_drop_dentry(sd);
+ sysfs_deactivate(sd);
+ sysfs_put(sd);
+ }
+
+ return acxt->cnt;
}
-static int init_file(struct inode * inode)
+/**
+ * sysfs_find_dirent - find sysfs_dirent with the given name
+ * @parent_sd: sysfs_dirent to search under
+ * @name: name to look for
+ *
+ * Look for sysfs_dirent with name @name under @parent_sd.
+ *
+ * LOCKING:
+ * mutex_lock(sysfs_mutex)
+ *
+ * RETURNS:
+ * Pointer to sysfs_dirent if found, NULL if not.
+ */
+struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
+ const unsigned char *name)
{
- inode->i_size = PAGE_SIZE;
- inode->i_fop = &sysfs_file_operations;
- return 0;
+ struct sysfs_dirent *sd;
+
+ for (sd = parent_sd->s_children; sd; sd = sd->s_sibling)
+ if (sysfs_type(sd) && !strcmp(sd->s_name, name))
+ return sd;
+ return NULL;
}
-static int init_symlink(struct inode * inode)
+/**
+ * sysfs_get_dirent - find and get sysfs_dirent with the given name
+ * @parent_sd: sysfs_dirent to search under
+ * @name: name to look for
+ *
+ * Look for sysfs_dirent with name @name under @parent_sd and get
+ * it if found.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep). Grabs sysfs_mutex.
+ *
+ * RETURNS:
+ * Pointer to sysfs_dirent if found, NULL if not.
+ */
+struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
+ const unsigned char *name)
{
- inode->i_op = &sysfs_symlink_inode_operations;
- return 0;
+ struct sysfs_dirent *sd;
+
+ mutex_lock(&sysfs_mutex);
+ sd = sysfs_find_dirent(parent_sd, name);
+ sysfs_get(sd);
+ mutex_unlock(&sysfs_mutex);
+
+ return sd;
}
-static int create_dir(struct kobject * k, struct dentry * p,
- const char * n, struct dentry ** d)
+static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
+ const char *name, struct sysfs_dirent **p_sd)
{
- int error;
umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO;
+ struct sysfs_addrm_cxt acxt;
+ struct sysfs_dirent *sd;
- mutex_lock(&p->d_inode->i_mutex);
- *d = lookup_one_len(n, p, strlen(n));
- if (!IS_ERR(*d)) {
- if (sysfs_dirent_exist(p->d_fsdata, n))
- error = -EEXIST;
- else
- error = sysfs_make_dirent(p->d_fsdata, *d, k, mode,
- SYSFS_DIR);
- if (!error) {
- error = sysfs_create(*d, mode, init_dir);
- if (!error) {
- inc_nlink(p->d_inode);
- (*d)->d_op = &sysfs_dentry_ops;
- d_rehash(*d);
- }
- }
- if (error && (error != -EEXIST)) {
- struct sysfs_dirent *sd = (*d)->d_fsdata;
- if (sd) {
- list_del_init(&sd->s_sibling);
- sysfs_put(sd);
- }
- d_drop(*d);
- }
- dput(*d);
- } else
- error = PTR_ERR(*d);
- mutex_unlock(&p->d_inode->i_mutex);
- return error;
-}
+ /* allocate */
+ sd = sysfs_new_dirent(name, mode, SYSFS_DIR);
+ if (!sd)
+ return -ENOMEM;
+ sd->s_elem.dir.kobj = kobj;
+ /* link in */
+ sysfs_addrm_start(&acxt, parent_sd);
+ if (!sysfs_find_dirent(parent_sd, name)) {
+ sysfs_add_one(&acxt, sd);
+ sysfs_link_sibling(sd);
+ }
+ if (sysfs_addrm_finish(&acxt)) {
+ *p_sd = sd;
+ return 0;
+ }
-int sysfs_create_subdir(struct kobject * k, const char * n, struct dentry ** d)
+ sysfs_put(sd);
+ return -EEXIST;
+}
+
+int sysfs_create_subdir(struct kobject *kobj, const char *name,
+ struct sysfs_dirent **p_sd)
{
- return create_dir(k,k->dentry,n,d);
+ return create_dir(kobj, kobj->sd, name, p_sd);
}
/**
* sysfs_create_dir - create a directory for an object.
* @kobj: object we're creating directory for.
- * @shadow_parent: parent parent object.
+ * @shadow_parent: parent object.
*/
-
-int sysfs_create_dir(struct kobject * kobj, struct dentry *shadow_parent)
+int sysfs_create_dir(struct kobject *kobj,
+ struct sysfs_dirent *shadow_parent_sd)
{
- struct dentry * dentry = NULL;
- struct dentry * parent;
+ struct sysfs_dirent *parent_sd, *sd;
int error = 0;
BUG_ON(!kobj);
- if (shadow_parent)
- parent = shadow_parent;
+ if (shadow_parent_sd)
+ parent_sd = shadow_parent_sd;
else if (kobj->parent)
- parent = kobj->parent->dentry;
+ parent_sd = kobj->parent->sd;
else if (sysfs_mount && sysfs_mount->mnt_sb)
- parent = sysfs_mount->mnt_sb->s_root;
+ parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata;
else
return -EFAULT;
- error = create_dir(kobj,parent,kobject_name(kobj),&dentry);
+ error = create_dir(kobj, parent_sd, kobject_name(kobj), &sd);
if (!error)
- kobj->dentry = dentry;
+ kobj->sd = sd;
return error;
}
-/* attaches attribute's sysfs_dirent to the dentry corresponding to the
- * attribute file
- */
-static int sysfs_attach_attr(struct sysfs_dirent * sd, struct dentry * dentry)
+static int sysfs_count_nlink(struct sysfs_dirent *sd)
{
- struct attribute * attr = NULL;
- struct bin_attribute * bin_attr = NULL;
- int (* init) (struct inode *) = NULL;
- int error = 0;
-
- if (sd->s_type & SYSFS_KOBJ_BIN_ATTR) {
- bin_attr = sd->s_element;
- attr = &bin_attr->attr;
- } else {
- attr = sd->s_element;
- init = init_file;
- }
+ struct sysfs_dirent *child;
+ int nr = 0;
- dentry->d_fsdata = sysfs_get(sd);
- /* protect sd->s_dentry against sysfs_d_iput */
- spin_lock(&sysfs_lock);
- sd->s_dentry = dentry;
- spin_unlock(&sysfs_lock);
- error = sysfs_create(dentry, (attr->mode & S_IALLUGO) | S_IFREG, init);
- if (error) {
- sysfs_put(sd);
- return error;
- }
-
- if (bin_attr) {
- dentry->d_inode->i_size = bin_attr->size;
- dentry->d_inode->i_fop = &bin_fops;
- }
- dentry->d_op = &sysfs_dentry_ops;
- d_rehash(dentry);
-
- return 0;
-}
-
-static int sysfs_attach_link(struct sysfs_dirent * sd, struct dentry * dentry)
-{
- int err = 0;
-
- dentry->d_fsdata = sysfs_get(sd);
- /* protect sd->s_dentry against sysfs_d_iput */
- spin_lock(&sysfs_lock);
- sd->s_dentry = dentry;
- spin_unlock(&sysfs_lock);
- err = sysfs_create(dentry, S_IFLNK|S_IRWXUGO, init_symlink);
- if (!err) {
- dentry->d_op = &sysfs_dentry_ops;
- d_rehash(dentry);
- } else
- sysfs_put(sd);
-
- return err;
+ for (child = sd->s_children; child; child = child->s_sibling)
+ if (sysfs_type(child) == SYSFS_DIR)
+ nr++;
+ return nr + 2;
}
static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
@@ -303,24 +761,60 @@ static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
{
struct sysfs_dirent * parent_sd = dentry->d_parent->d_fsdata;
struct sysfs_dirent * sd;
- int err = 0;
+ struct bin_attribute *bin_attr;
+ struct inode *inode;
+ int found = 0;
- list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
- if (sd->s_type & SYSFS_NOT_PINNED) {
- const unsigned char * name = sysfs_get_name(sd);
+ for (sd = parent_sd->s_children; sd; sd = sd->s_sibling) {
+ if (sysfs_type(sd) &&
+ !strcmp(sd->s_name, dentry->d_name.name)) {
+ found = 1;
+ break;
+ }
+ }
- if (strcmp(name, dentry->d_name.name))
- continue;
+ /* no such entry */
+ if (!found)
+ return NULL;
- if (sd->s_type & SYSFS_KOBJ_LINK)
- err = sysfs_attach_link(sd, dentry);
- else
- err = sysfs_attach_attr(sd, dentry);
+ /* attach dentry and inode */
+ inode = sysfs_get_inode(sd);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_lock(&sysfs_mutex);
+
+ if (inode->i_state & I_NEW) {
+ /* initialize inode according to type */
+ switch (sysfs_type(sd)) {
+ case SYSFS_DIR:
+ inode->i_op = &sysfs_dir_inode_operations;
+ inode->i_fop = &sysfs_dir_operations;
+ inode->i_nlink = sysfs_count_nlink(sd);
+ break;
+ case SYSFS_KOBJ_ATTR:
+ inode->i_size = PAGE_SIZE;
+ inode->i_fop = &sysfs_file_operations;
+ break;
+ case SYSFS_KOBJ_BIN_ATTR:
+ bin_attr = sd->s_elem.bin_attr.bin_attr;
+ inode->i_size = bin_attr->size;
+ inode->i_fop = &bin_fops;
break;
+ case SYSFS_KOBJ_LINK:
+ inode->i_op = &sysfs_symlink_inode_operations;
+ break;
+ default:
+ BUG();
}
}
- return ERR_PTR(err);
+ sysfs_instantiate(dentry, inode);
+ sysfs_attach_dentry(sd, dentry);
+
+ mutex_unlock(&sysfs_mutex);
+
+ return NULL;
}
const struct inode_operations sysfs_dir_inode_operations = {
@@ -328,58 +822,46 @@ const struct inode_operations sysfs_dir_inode_operations = {
.setattr = sysfs_setattr,
};
-static void remove_dir(struct dentry * d)
+static void remove_dir(struct sysfs_dirent *sd)
{
- struct dentry * parent = dget(d->d_parent);
- struct sysfs_dirent * sd;
-
- mutex_lock(&parent->d_inode->i_mutex);
- d_delete(d);
- sd = d->d_fsdata;
- list_del_init(&sd->s_sibling);
- sysfs_put(sd);
- if (d->d_inode)
- simple_rmdir(parent->d_inode,d);
-
- pr_debug(" o %s removing done (%d)\n",d->d_name.name,
- atomic_read(&d->d_count));
+ struct sysfs_addrm_cxt acxt;
- mutex_unlock(&parent->d_inode->i_mutex);
- dput(parent);
+ sysfs_addrm_start(&acxt, sd->s_parent);
+ sysfs_unlink_sibling(sd);
+ sysfs_remove_one(&acxt, sd);
+ sysfs_addrm_finish(&acxt);
}
-void sysfs_remove_subdir(struct dentry * d)
+void sysfs_remove_subdir(struct sysfs_dirent *sd)
{
- remove_dir(d);
+ remove_dir(sd);
}
-static void __sysfs_remove_dir(struct dentry *dentry)
+static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd)
{
- struct sysfs_dirent * parent_sd;
- struct sysfs_dirent * sd, * tmp;
+ struct sysfs_addrm_cxt acxt;
+ struct sysfs_dirent **pos;
- dget(dentry);
- if (!dentry)
+ if (!dir_sd)
return;
- pr_debug("sysfs %s: removing dir\n",dentry->d_name.name);
- mutex_lock(&dentry->d_inode->i_mutex);
- parent_sd = dentry->d_fsdata;
- list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) {
- if (!sd->s_element || !(sd->s_type & SYSFS_NOT_PINNED))
- continue;
- list_del_init(&sd->s_sibling);
- sysfs_drop_dentry(sd, dentry);
- sysfs_put(sd);
+ pr_debug("sysfs %s: removing dir\n", dir_sd->s_name);
+ sysfs_addrm_start(&acxt, dir_sd);
+ pos = &dir_sd->s_children;
+ while (*pos) {
+ struct sysfs_dirent *sd = *pos;
+
+ if (sysfs_type(sd) && sysfs_type(sd) != SYSFS_DIR) {
+ *pos = sd->s_sibling;
+ sd->s_sibling = NULL;
+ sysfs_remove_one(&acxt, sd);
+ } else
+ pos = &(*pos)->s_sibling;
}
- mutex_unlock(&dentry->d_inode->i_mutex);
+ sysfs_addrm_finish(&acxt);
- remove_dir(dentry);
- /**
- * Drop reference from dget() on entrance.
- */
- dput(dentry);
+ remove_dir(dir_sd);
}
/**
@@ -393,102 +875,166 @@ static void __sysfs_remove_dir(struct dentry *dentry)
void sysfs_remove_dir(struct kobject * kobj)
{
- __sysfs_remove_dir(kobj->dentry);
- kobj->dentry = NULL;
+ struct sysfs_dirent *sd = kobj->sd;
+
+ spin_lock(&sysfs_assoc_lock);
+ kobj->sd = NULL;
+ spin_unlock(&sysfs_assoc_lock);
+
+ __sysfs_remove_dir(sd);
}
-int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent,
+int sysfs_rename_dir(struct kobject *kobj, struct sysfs_dirent *new_parent_sd,
const char *new_name)
{
- int error = 0;
- struct dentry * new_dentry;
+ struct sysfs_dirent *sd = kobj->sd;
+ struct dentry *new_parent = NULL;
+ struct dentry *old_dentry = NULL, *new_dentry = NULL;
+ const char *dup_name = NULL;
+ int error;
- if (!new_parent)
- return -EFAULT;
+ /* get dentries */
+ old_dentry = sysfs_get_dentry(sd);
+ if (IS_ERR(old_dentry)) {
+ error = PTR_ERR(old_dentry);
+ goto out_dput;
+ }
- down_write(&sysfs_rename_sem);
+ new_parent = sysfs_get_dentry(new_parent_sd);
+ if (IS_ERR(new_parent)) {
+ error = PTR_ERR(new_parent);
+ goto out_dput;
+ }
+
+ /* lock new_parent and get dentry for new name */
mutex_lock(&new_parent->d_inode->i_mutex);
new_dentry = lookup_one_len(new_name, new_parent, strlen(new_name));
- if (!IS_ERR(new_dentry)) {
- /* By allowing two different directories with the
- * same d_parent we allow this routine to move
- * between different shadows of the same directory
- */
- if (kobj->dentry->d_parent->d_inode != new_parent->d_inode)
- return -EINVAL;
- else if (new_dentry->d_parent->d_inode != new_parent->d_inode)
- error = -EINVAL;
- else if (new_dentry == kobj->dentry)
- error = -EINVAL;
- else if (!new_dentry->d_inode) {
- error = kobject_set_name(kobj, "%s", new_name);
- if (!error) {
- struct sysfs_dirent *sd, *parent_sd;
-
- d_add(new_dentry, NULL);
- d_move(kobj->dentry, new_dentry);
-
- sd = kobj->dentry->d_fsdata;
- parent_sd = new_parent->d_fsdata;
-
- list_del_init(&sd->s_sibling);
- list_add(&sd->s_sibling, &parent_sd->s_children);
- }
- else
- d_drop(new_dentry);
- } else
- error = -EEXIST;
- dput(new_dentry);
+ if (IS_ERR(new_dentry)) {
+ error = PTR_ERR(new_dentry);
+ goto out_unlock;
}
- mutex_unlock(&new_parent->d_inode->i_mutex);
- up_write(&sysfs_rename_sem);
+ /* By allowing two different directories with the same
+ * d_parent we allow this routine to move between different
+ * shadows of the same directory
+ */
+ error = -EINVAL;
+ if (old_dentry->d_parent->d_inode != new_parent->d_inode ||
+ new_dentry->d_parent->d_inode != new_parent->d_inode ||
+ old_dentry == new_dentry)
+ goto out_unlock;
+
+ error = -EEXIST;
+ if (new_dentry->d_inode)
+ goto out_unlock;
+
+ /* rename kobject and sysfs_dirent */
+ error = -ENOMEM;
+ new_name = dup_name = kstrdup(new_name, GFP_KERNEL);
+ if (!new_name)
+ goto out_drop;
+
+ error = kobject_set_name(kobj, "%s", new_name);
+ if (error)
+ goto out_drop;
+
+ dup_name = sd->s_name;
+ sd->s_name = new_name;
+
+ /* move under the new parent */
+ d_add(new_dentry, NULL);
+ d_move(sd->s_dentry, new_dentry);
+
+ mutex_lock(&sysfs_mutex);
+
+ sysfs_unlink_sibling(sd);
+ sysfs_get(new_parent_sd);
+ sysfs_put(sd->s_parent);
+ sd->s_parent = new_parent_sd;
+ sysfs_link_sibling(sd);
+
+ mutex_unlock(&sysfs_mutex);
+
+ error = 0;
+ goto out_unlock;
+
+ out_drop:
+ d_drop(new_dentry);
+ out_unlock:
+ mutex_unlock(&new_parent->d_inode->i_mutex);
+ out_dput:
+ kfree(dup_name);
+ dput(new_parent);
+ dput(old_dentry);
+ dput(new_dentry);
return error;
}
-int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent)
+int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj)
{
- struct dentry *old_parent_dentry, *new_parent_dentry, *new_dentry;
- struct sysfs_dirent *new_parent_sd, *sd;
+ struct sysfs_dirent *sd = kobj->sd;
+ struct sysfs_dirent *new_parent_sd;
+ struct dentry *old_parent, *new_parent = NULL;
+ struct dentry *old_dentry = NULL, *new_dentry = NULL;
int error;
- old_parent_dentry = kobj->parent ?
- kobj->parent->dentry : sysfs_mount->mnt_sb->s_root;
- new_parent_dentry = new_parent ?
- new_parent->dentry : sysfs_mount->mnt_sb->s_root;
+ BUG_ON(!sd->s_parent);
+ new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root;
+
+ /* get dentries */
+ old_dentry = sysfs_get_dentry(sd);
+ if (IS_ERR(old_dentry)) {
+ error = PTR_ERR(old_dentry);
+ goto out_dput;
+ }
+ old_parent = sd->s_parent->s_dentry;
+
+ new_parent = sysfs_get_dentry(new_parent_sd);
+ if (IS_ERR(new_parent)) {
+ error = PTR_ERR(new_parent);
+ goto out_dput;
+ }
- if (old_parent_dentry->d_inode == new_parent_dentry->d_inode)
- return 0; /* nothing to move */
+ if (old_parent->d_inode == new_parent->d_inode) {
+ error = 0;
+ goto out_dput; /* nothing to move */
+ }
again:
- mutex_lock(&old_parent_dentry->d_inode->i_mutex);
- if (!mutex_trylock(&new_parent_dentry->d_inode->i_mutex)) {
- mutex_unlock(&old_parent_dentry->d_inode->i_mutex);
+ mutex_lock(&old_parent->d_inode->i_mutex);
+ if (!mutex_trylock(&new_parent->d_inode->i_mutex)) {
+ mutex_unlock(&old_parent->d_inode->i_mutex);
goto again;
}
- new_parent_sd = new_parent_dentry->d_fsdata;
- sd = kobj->dentry->d_fsdata;
-
- new_dentry = lookup_one_len(kobj->name, new_parent_dentry,
- strlen(kobj->name));
+ new_dentry = lookup_one_len(kobj->name, new_parent, strlen(kobj->name));
if (IS_ERR(new_dentry)) {
error = PTR_ERR(new_dentry);
- goto out;
+ goto out_unlock;
} else
error = 0;
d_add(new_dentry, NULL);
- d_move(kobj->dentry, new_dentry);
+ d_move(sd->s_dentry, new_dentry);
dput(new_dentry);
/* Remove from old parent's list and insert into new parent's list. */
- list_del_init(&sd->s_sibling);
- list_add(&sd->s_sibling, &new_parent_sd->s_children);
+ mutex_lock(&sysfs_mutex);
+
+ sysfs_unlink_sibling(sd);
+ sysfs_get(new_parent_sd);
+ sysfs_put(sd->s_parent);
+ sd->s_parent = new_parent_sd;
+ sysfs_link_sibling(sd);
-out:
- mutex_unlock(&new_parent_dentry->d_inode->i_mutex);
- mutex_unlock(&old_parent_dentry->d_inode->i_mutex);
+ mutex_unlock(&sysfs_mutex);
+ out_unlock:
+ mutex_unlock(&new_parent->d_inode->i_mutex);
+ mutex_unlock(&old_parent->d_inode->i_mutex);
+ out_dput:
+ dput(new_parent);
+ dput(old_dentry);
+ dput(new_dentry);
return error;
}
@@ -496,23 +1042,27 @@ static int sysfs_dir_open(struct inode *inode, struct file *file)
{
struct dentry * dentry = file->f_path.dentry;
struct sysfs_dirent * parent_sd = dentry->d_fsdata;
+ struct sysfs_dirent * sd;
- mutex_lock(&dentry->d_inode->i_mutex);
- file->private_data = sysfs_new_dirent(parent_sd, NULL);
- mutex_unlock(&dentry->d_inode->i_mutex);
-
- return file->private_data ? 0 : -ENOMEM;
+ sd = sysfs_new_dirent("_DIR_", 0, 0);
+ if (sd) {
+ mutex_lock(&sysfs_mutex);
+ sd->s_parent = sysfs_get(parent_sd);
+ sysfs_link_sibling(sd);
+ mutex_unlock(&sysfs_mutex);
+ }
+ file->private_data = sd;
+ return sd ? 0 : -ENOMEM;
}
static int sysfs_dir_close(struct inode *inode, struct file *file)
{
- struct dentry * dentry = file->f_path.dentry;
struct sysfs_dirent * cursor = file->private_data;
- mutex_lock(&dentry->d_inode->i_mutex);
- list_del_init(&cursor->s_sibling);
- mutex_unlock(&dentry->d_inode->i_mutex);
+ mutex_lock(&sysfs_mutex);
+ sysfs_unlink_sibling(cursor);
+ mutex_unlock(&sysfs_mutex);
release_sysfs_dirent(cursor);
@@ -530,7 +1080,7 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
struct dentry *dentry = filp->f_path.dentry;
struct sysfs_dirent * parent_sd = dentry->d_fsdata;
struct sysfs_dirent *cursor = filp->private_data;
- struct list_head *p, *q = &cursor->s_sibling;
+ struct sysfs_dirent **pos;
ino_t ino;
int i = filp->f_pos;
@@ -543,38 +1093,52 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
i++;
/* fallthrough */
case 1:
- ino = parent_ino(dentry);
+ if (parent_sd->s_parent)
+ ino = parent_sd->s_parent->s_ino;
+ else
+ ino = parent_sd->s_ino;
if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
break;
filp->f_pos++;
i++;
/* fallthrough */
default:
+ mutex_lock(&sysfs_mutex);
+
+ pos = &parent_sd->s_children;
+ while (*pos != cursor)
+ pos = &(*pos)->s_sibling;
+
+ /* unlink cursor */
+ *pos = cursor->s_sibling;
+
if (filp->f_pos == 2)
- list_move(q, &parent_sd->s_children);
+ pos = &parent_sd->s_children;
- for (p=q->next; p!= &parent_sd->s_children; p=p->next) {
- struct sysfs_dirent *next;
+ for ( ; *pos; pos = &(*pos)->s_sibling) {
+ struct sysfs_dirent *next = *pos;
const char * name;
int len;
- next = list_entry(p, struct sysfs_dirent,
- s_sibling);
- if (!next->s_element)
+ if (!sysfs_type(next))
continue;
- name = sysfs_get_name(next);
+ name = next->s_name;
len = strlen(name);
ino = next->s_ino;
if (filldir(dirent, name, len, filp->f_pos, ino,
dt_type(next)) < 0)
- return 0;
+ break;
- list_move(q, p);
- p = q;
filp->f_pos++;
}
+
+ /* put cursor back in */
+ cursor->s_sibling = *pos;
+ *pos = cursor;
+
+ mutex_unlock(&sysfs_mutex);
}
return 0;
}
@@ -583,7 +1147,6 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
{
struct dentry * dentry = file->f_path.dentry;
- mutex_lock(&dentry->d_inode->i_mutex);
switch (origin) {
case 1:
offset += file->f_pos;
@@ -591,31 +1154,35 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
if (offset >= 0)
break;
default:
- mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
return -EINVAL;
}
if (offset != file->f_pos) {
+ mutex_lock(&sysfs_mutex);
+
file->f_pos = offset;
if (file->f_pos >= 2) {
struct sysfs_dirent *sd = dentry->d_fsdata;
struct sysfs_dirent *cursor = file->private_data;
- struct list_head *p;
+ struct sysfs_dirent **pos;
loff_t n = file->f_pos - 2;
- list_del(&cursor->s_sibling);
- p = sd->s_children.next;
- while (n && p != &sd->s_children) {
- struct sysfs_dirent *next;
- next = list_entry(p, struct sysfs_dirent,
- s_sibling);
- if (next->s_element)
+ sysfs_unlink_sibling(cursor);
+
+ pos = &sd->s_children;
+ while (n && *pos) {
+ struct sysfs_dirent *next = *pos;
+ if (sysfs_type(next))
n--;
- p = p->next;
+ pos = &(*pos)->s_sibling;
}
- list_add_tail(&cursor->s_sibling, p);
+
+ cursor->s_sibling = *pos;
+ *pos = cursor;
}
+
+ mutex_unlock(&sysfs_mutex);
}
- mutex_unlock(&dentry->d_inode->i_mutex);
+
return offset;
}
@@ -628,12 +1195,20 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
int sysfs_make_shadowed_dir(struct kobject *kobj,
void * (*follow_link)(struct dentry *, struct nameidata *))
{
+ struct dentry *dentry;
struct inode *inode;
struct inode_operations *i_op;
- inode = kobj->dentry->d_inode;
- if (inode->i_op != &sysfs_dir_inode_operations)
+ /* get dentry for @kobj->sd, dentry of a shadowed dir is pinned */
+ dentry = sysfs_get_dentry(kobj->sd);
+ if (IS_ERR(dentry))
+ return PTR_ERR(dentry);
+
+ inode = dentry->d_inode;
+ if (inode->i_op != &sysfs_dir_inode_operations) {
+ dput(dentry);
return -EINVAL;
+ }
i_op = kmalloc(sizeof(*i_op), GFP_KERNEL);
if (!i_op)
@@ -658,54 +1233,72 @@ int sysfs_make_shadowed_dir(struct kobject *kobj,
* directory.
*/
-struct dentry *sysfs_create_shadow_dir(struct kobject *kobj)
+struct sysfs_dirent *sysfs_create_shadow_dir(struct kobject *kobj)
{
- struct sysfs_dirent *sd;
- struct dentry *parent, *dir, *shadow;
+ struct sysfs_dirent *parent_sd = kobj->sd->s_parent;
+ struct dentry *dir, *parent, *shadow;
struct inode *inode;
+ struct sysfs_dirent *sd;
+ struct sysfs_addrm_cxt acxt;
- dir = kobj->dentry;
- inode = dir->d_inode;
+ dir = sysfs_get_dentry(kobj->sd);
+ if (IS_ERR(dir)) {
+ sd = (void *)dir;
+ goto out;
+ }
parent = dir->d_parent;
- shadow = ERR_PTR(-EINVAL);
+
+ inode = dir->d_inode;
+ sd = ERR_PTR(-EINVAL);
if (!sysfs_is_shadowed_inode(inode))
- goto out;
+ goto out_dput;
shadow = d_alloc(parent, &dir->d_name);
if (!shadow)
goto nomem;
- sd = __sysfs_make_dirent(shadow, kobj, inode->i_mode, SYSFS_DIR);
+ sd = sysfs_new_dirent("_SHADOW_", inode->i_mode, SYSFS_DIR);
if (!sd)
goto nomem;
+ sd->s_elem.dir.kobj = kobj;
+ sysfs_addrm_start(&acxt, parent_sd);
+
+ /* add but don't link into children list */
+ sysfs_add_one(&acxt, sd);
+
+ /* attach and instantiate dentry */
+ sysfs_attach_dentry(sd, shadow);
d_instantiate(shadow, igrab(inode));
- inc_nlink(inode);
- inc_nlink(parent->d_inode);
- shadow->d_op = &sysfs_dentry_ops;
+ inc_nlink(inode); /* tj: synchronization? */
+
+ sysfs_addrm_finish(&acxt);
dget(shadow); /* Extra count - pin the dentry in core */
-out:
- return shadow;
-nomem:
+ goto out_dput;
+
+ nomem:
dput(shadow);
- shadow = ERR_PTR(-ENOMEM);
- goto out;
+ sd = ERR_PTR(-ENOMEM);
+ out_dput:
+ dput(dir);
+ out:
+ return sd;
}
/**
* sysfs_remove_shadow_dir - remove an object's directory.
- * @shadow: dentry of shadow directory
+ * @shadow_sd: sysfs_dirent of shadow directory
*
* The only thing special about this is that we remove any files in
* the directory before we remove the directory, and we've inlined
* what used to be sysfs_rmdir() below, instead of calling separately.
*/
-void sysfs_remove_shadow_dir(struct dentry *shadow)
+void sysfs_remove_shadow_dir(struct sysfs_dirent *shadow_sd)
{
- __sysfs_remove_dir(shadow);
+ __sysfs_remove_dir(shadow_sd);
}
const struct file_operations sysfs_dir_operations = {
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index b502c7197ec..cc497994b2a 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -50,29 +50,15 @@ static struct sysfs_ops subsys_sysfs_ops = {
.store = subsys_attr_store,
};
-/**
- * add_to_collection - add buffer to a collection
- * @buffer: buffer to be added
- * @node: inode of set to add to
- */
-
-static inline void
-add_to_collection(struct sysfs_buffer *buffer, struct inode *node)
-{
- struct sysfs_buffer_collection *set = node->i_private;
-
- mutex_lock(&node->i_mutex);
- list_add(&buffer->associates, &set->associates);
- mutex_unlock(&node->i_mutex);
-}
-
-static inline void
-remove_from_collection(struct sysfs_buffer *buffer, struct inode *node)
-{
- mutex_lock(&node->i_mutex);
- list_del(&buffer->associates);
- mutex_unlock(&node->i_mutex);
-}
+struct sysfs_buffer {
+ size_t count;
+ loff_t pos;
+ char * page;
+ struct sysfs_ops * ops;
+ struct semaphore sem;
+ int needs_read_fill;
+ int event;
+};
/**
* fill_read_buffer - allocate and fill buffer from object.
@@ -87,9 +73,8 @@ remove_from_collection(struct sysfs_buffer *buffer, struct inode *node)
*/
static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer)
{
- struct sysfs_dirent * sd = dentry->d_fsdata;
- struct attribute * attr = to_attr(dentry);
- struct kobject * kobj = to_kobj(dentry->d_parent);
+ struct sysfs_dirent *attr_sd = dentry->d_fsdata;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
struct sysfs_ops * ops = buffer->ops;
int ret = 0;
ssize_t count;
@@ -99,8 +84,15 @@ static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer
if (!buffer->page)
return -ENOMEM;
- buffer->event = atomic_read(&sd->s_event);
- count = ops->show(kobj,attr,buffer->page);
+ /* need attr_sd for attr and ops, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
+
+ buffer->event = atomic_read(&attr_sd->s_event);
+ count = ops->show(kobj, attr_sd->s_elem.attr.attr, buffer->page);
+
+ sysfs_put_active_two(attr_sd);
+
BUG_ON(count > (ssize_t)PAGE_SIZE);
if (count >= 0) {
buffer->needs_read_fill = 0;
@@ -138,10 +130,7 @@ sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos)
down(&buffer->sem);
if (buffer->needs_read_fill) {
- if (buffer->orphaned)
- retval = -ENODEV;
- else
- retval = fill_read_buffer(file->f_path.dentry,buffer);
+ retval = fill_read_buffer(file->f_path.dentry,buffer);
if (retval)
goto out;
}
@@ -196,14 +185,23 @@ fill_write_buffer(struct sysfs_buffer * buffer, const char __user * buf, size_t
* passing the buffer that we acquired in fill_write_buffer().
*/
-static int
+static int
flush_write_buffer(struct dentry * dentry, struct sysfs_buffer * buffer, size_t count)
{
- struct attribute * attr = to_attr(dentry);
- struct kobject * kobj = to_kobj(dentry->d_parent);
+ struct sysfs_dirent *attr_sd = dentry->d_fsdata;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
struct sysfs_ops * ops = buffer->ops;
+ int rc;
+
+ /* need attr_sd for attr and ops, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
+
+ rc = ops->store(kobj, attr_sd->s_elem.attr.attr, buffer->page, count);
- return ops->store(kobj,attr,buffer->page,count);
+ sysfs_put_active_two(attr_sd);
+
+ return rc;
}
@@ -231,37 +229,26 @@ sysfs_write_file(struct file *file, const char __user *buf, size_t count, loff_t
ssize_t len;
down(&buffer->sem);
- if (buffer->orphaned) {
- len = -ENODEV;
- goto out;
- }
len = fill_write_buffer(buffer, buf, count);
if (len > 0)
len = flush_write_buffer(file->f_path.dentry, buffer, len);
if (len > 0)
*ppos += len;
-out:
up(&buffer->sem);
return len;
}
static int sysfs_open_file(struct inode *inode, struct file *file)
{
- struct kobject *kobj = sysfs_get_kobject(file->f_path.dentry->d_parent);
- struct attribute * attr = to_attr(file->f_path.dentry);
- struct sysfs_buffer_collection *set;
+ struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
struct sysfs_buffer * buffer;
struct sysfs_ops * ops = NULL;
- int error = 0;
-
- if (!kobj || !attr)
- goto Einval;
+ int error;
- /* Grab the module reference for this attribute if we have one */
- if (!try_module_get(attr->owner)) {
- error = -ENODEV;
- goto Done;
- }
+ /* need attr_sd for attr and ops, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
/* if the kobject has no ktype, then we assume that it is a subsystem
* itself, and use ops for it.
@@ -273,33 +260,21 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
else
ops = &subsys_sysfs_ops;
+ error = -EACCES;
+
/* No sysfs operations, either from having no subsystem,
* or the subsystem have no operations.
*/
if (!ops)
- goto Eaccess;
-
- /* make sure we have a collection to add our buffers to */
- mutex_lock(&inode->i_mutex);
- if (!(set = inode->i_private)) {
- if (!(set = inode->i_private = kmalloc(sizeof(struct sysfs_buffer_collection), GFP_KERNEL))) {
- error = -ENOMEM;
- goto Done;
- } else {
- INIT_LIST_HEAD(&set->associates);
- }
- }
- mutex_unlock(&inode->i_mutex);
+ goto err_out;
/* File needs write support.
* The inode's perms must say it's ok,
* and we must have a store method.
*/
if (file->f_mode & FMODE_WRITE) {
-
if (!(inode->i_mode & S_IWUGO) || !ops->store)
- goto Eaccess;
-
+ goto err_out;
}
/* File needs read support.
@@ -308,48 +283,38 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
*/
if (file->f_mode & FMODE_READ) {
if (!(inode->i_mode & S_IRUGO) || !ops->show)
- goto Eaccess;
+ goto err_out;
}
/* No error? Great, allocate a buffer for the file, and store it
* it in file->private_data for easy access.
*/
+ error = -ENOMEM;
buffer = kzalloc(sizeof(struct sysfs_buffer), GFP_KERNEL);
- if (buffer) {
- INIT_LIST_HEAD(&buffer->associates);
- init_MUTEX(&buffer->sem);
- buffer->needs_read_fill = 1;
- buffer->ops = ops;
- add_to_collection(buffer, inode);
- file->private_data = buffer;
- } else
- error = -ENOMEM;
- goto Done;
-
- Einval:
- error = -EINVAL;
- goto Done;
- Eaccess:
- error = -EACCES;
- module_put(attr->owner);
- Done:
- if (error)
- kobject_put(kobj);
+ if (!buffer)
+ goto err_out;
+
+ init_MUTEX(&buffer->sem);
+ buffer->needs_read_fill = 1;
+ buffer->ops = ops;
+ file->private_data = buffer;
+
+ /* open succeeded, put active references and pin attr_sd */
+ sysfs_put_active_two(attr_sd);
+ sysfs_get(attr_sd);
+ return 0;
+
+ err_out:
+ sysfs_put_active_two(attr_sd);
return error;
}
static int sysfs_release(struct inode * inode, struct file * filp)
{
- struct kobject * kobj = to_kobj(filp->f_path.dentry->d_parent);
- struct attribute * attr = to_attr(filp->f_path.dentry);
- struct module * owner = attr->owner;
- struct sysfs_buffer * buffer = filp->private_data;
+ struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
+ struct sysfs_buffer *buffer = filp->private_data;
- if (buffer)
- remove_from_collection(buffer, inode);
- kobject_put(kobj);
- /* After this point, attr should not be accessed. */
- module_put(owner);
+ sysfs_put(attr_sd);
if (buffer) {
if (buffer->page)
@@ -376,57 +341,43 @@ static int sysfs_release(struct inode * inode, struct file * filp)
static unsigned int sysfs_poll(struct file *filp, poll_table *wait)
{
struct sysfs_buffer * buffer = filp->private_data;
- struct kobject * kobj = to_kobj(filp->f_path.dentry->d_parent);
- struct sysfs_dirent * sd = filp->f_path.dentry->d_fsdata;
- int res = 0;
+ struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
+
+ /* need parent for the kobj, grab both */
+ if (!sysfs_get_active_two(attr_sd))
+ goto trigger;
poll_wait(filp, &kobj->poll, wait);
- if (buffer->event != atomic_read(&sd->s_event)) {
- res = POLLERR|POLLPRI;
- buffer->needs_read_fill = 1;
- }
+ sysfs_put_active_two(attr_sd);
- return res;
-}
+ if (buffer->event != atomic_read(&attr_sd->s_event))
+ goto trigger;
+ return 0;
-static struct dentry *step_down(struct dentry *dir, const char * name)
-{
- struct dentry * de;
-
- if (dir == NULL || dir->d_inode == NULL)
- return NULL;
-
- mutex_lock(&dir->d_inode->i_mutex);
- de = lookup_one_len(name, dir, strlen(name));
- mutex_unlock(&dir->d_inode->i_mutex);
- dput(dir);
- if (IS_ERR(de))
- return NULL;
- if (de->d_inode == NULL) {
- dput(de);
- return NULL;
- }
- return de;
+ trigger:
+ buffer->needs_read_fill = 1;
+ return POLLERR|POLLPRI;
}
-void sysfs_notify(struct kobject * k, char *dir, char *attr)
+void sysfs_notify(struct kobject *k, char *dir, char *attr)
{
- struct dentry *de = k->dentry;
- if (de)
- dget(de);
- if (de && dir)
- de = step_down(de, dir);
- if (de && attr)
- de = step_down(de, attr);
- if (de) {
- struct sysfs_dirent * sd = de->d_fsdata;
- if (sd)
- atomic_inc(&sd->s_event);
+ struct sysfs_dirent *sd = k->sd;
+
+ mutex_lock(&sysfs_mutex);
+
+ if (sd && dir)
+ sd = sysfs_find_dirent(sd, dir);
+ if (sd && attr)
+ sd = sysfs_find_dirent(sd, attr);
+ if (sd) {
+ atomic_inc(&sd->s_event);
wake_up_interruptible(&k->poll);
- dput(de);
}
+
+ mutex_unlock(&sysfs_mutex);
}
EXPORT_SYMBOL_GPL(sysfs_notify);
@@ -440,19 +391,30 @@ const struct file_operations sysfs_file_operations = {
};
-int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type)
+int sysfs_add_file(struct sysfs_dirent *dir_sd, const struct attribute *attr,
+ int type)
{
- struct sysfs_dirent * parent_sd = dir->d_fsdata;
umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
- int error = -EEXIST;
+ struct sysfs_addrm_cxt acxt;
+ struct sysfs_dirent *sd;
- mutex_lock(&dir->d_inode->i_mutex);
- if (!sysfs_dirent_exist(parent_sd, attr->name))
- error = sysfs_make_dirent(parent_sd, NULL, (void *)attr,
- mode, type);
- mutex_unlock(&dir->d_inode->i_mutex);
+ sd = sysfs_new_dirent(attr->name, mode, type);
+ if (!sd)
+ return -ENOMEM;
+ sd->s_elem.attr.attr = (void *)attr;
- return error;
+ sysfs_addrm_start(&acxt, dir_sd);
+
+ if (!sysfs_find_dirent(dir_sd, attr->name)) {
+ sysfs_add_one(&acxt, sd);
+ sysfs_link_sibling(sd);
+ }
+
+ if (sysfs_addrm_finish(&acxt))
+ return 0;
+
+ sysfs_put(sd);
+ return -EEXIST;
}
@@ -464,9 +426,9 @@ int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type)
int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
{
- BUG_ON(!kobj || !kobj->dentry || !attr);
+ BUG_ON(!kobj || !kobj->sd || !attr);
- return sysfs_add_file(kobj->dentry, attr, SYSFS_KOBJ_ATTR);
+ return sysfs_add_file(kobj->sd, attr, SYSFS_KOBJ_ATTR);
}
@@ -480,16 +442,16 @@ int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
int sysfs_add_file_to_group(struct kobject *kobj,
const struct attribute *attr, const char *group)
{
- struct dentry *dir;
+ struct sysfs_dirent *dir_sd;
int error;
- dir = lookup_one_len(group, kobj->dentry, strlen(group));
- if (IS_ERR(dir))
- error = PTR_ERR(dir);
- else {
- error = sysfs_add_file(dir, attr, SYSFS_KOBJ_ATTR);
- dput(dir);
- }
+ dir_sd = sysfs_get_dirent(kobj->sd, group);
+ if (!dir_sd)
+ return -ENOENT;
+
+ error = sysfs_add_file(dir_sd, attr, SYSFS_KOBJ_ATTR);
+ sysfs_put(dir_sd);
+
return error;
}
EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
@@ -502,30 +464,31 @@ EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
*/
int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
{
- struct dentry * dir = kobj->dentry;
- struct dentry * victim;
- int res = -ENOENT;
-
- mutex_lock(&dir->d_inode->i_mutex);
- victim = lookup_one_len(attr->name, dir, strlen(attr->name));
- if (!IS_ERR(victim)) {
- /* make sure dentry is really there */
- if (victim->d_inode &&
- (victim->d_parent->d_inode == dir->d_inode)) {
- victim->d_inode->i_mtime = CURRENT_TIME;
- fsnotify_modify(victim);
- res = 0;
- } else
- d_drop(victim);
-
- /**
- * Drop the reference acquired from lookup_one_len() above.
- */
- dput(victim);
+ struct sysfs_dirent *victim_sd = NULL;
+ struct dentry *victim = NULL;
+ int rc;
+
+ rc = -ENOENT;
+ victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
+ if (!victim_sd)
+ goto out;
+
+ victim = sysfs_get_dentry(victim_sd);
+ if (IS_ERR(victim)) {
+ rc = PTR_ERR(victim);
+ victim = NULL;
+ goto out;
}
- mutex_unlock(&dir->d_inode->i_mutex);
- return res;
+ mutex_lock(&victim->d_inode->i_mutex);
+ victim->d_inode->i_mtime = CURRENT_TIME;
+ fsnotify_modify(victim);
+ mutex_unlock(&victim->d_inode->i_mutex);
+ rc = 0;
+ out:
+ dput(victim);
+ sysfs_put(victim_sd);
+ return rc;
}
@@ -538,30 +501,34 @@ int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
*/
int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
{
- struct dentry *dir = kobj->dentry;
- struct dentry *victim;
+ struct sysfs_dirent *victim_sd = NULL;
+ struct dentry *victim = NULL;
struct inode * inode;
struct iattr newattrs;
- int res = -ENOENT;
-
- mutex_lock(&dir->d_inode->i_mutex);
- victim = lookup_one_len(attr->name, dir, strlen(attr->name));
- if (!IS_ERR(victim)) {
- if (victim->d_inode &&
- (victim->d_parent->d_inode == dir->d_inode)) {
- inode = victim->d_inode;
- mutex_lock(&inode->i_mutex);
- newattrs.ia_mode = (mode & S_IALLUGO) |
- (inode->i_mode & ~S_IALLUGO);
- newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
- res = notify_change(victim, &newattrs);
- mutex_unlock(&inode->i_mutex);
- }
- dput(victim);
+ int rc;
+
+ rc = -ENOENT;
+ victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
+ if (!victim_sd)
+ goto out;
+
+ victim = sysfs_get_dentry(victim_sd);
+ if (IS_ERR(victim)) {
+ rc = PTR_ERR(victim);
+ victim = NULL;
+ goto out;
}
- mutex_unlock(&dir->d_inode->i_mutex);
- return res;
+ inode = victim->d_inode;
+ mutex_lock(&inode->i_mutex);
+ newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
+ newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
+ rc = notify_change(victim, &newattrs);
+ mutex_unlock(&inode->i_mutex);
+ out:
+ dput(victim);
+ sysfs_put(victim_sd);
+ return rc;
}
EXPORT_SYMBOL_GPL(sysfs_chmod_file);
@@ -576,7 +543,7 @@ EXPORT_SYMBOL_GPL(sysfs_chmod_file);
void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr)
{
- sysfs_hash_and_remove(kobj->dentry, attr->name);
+ sysfs_hash_and_remove(kobj->sd, attr->name);
}
@@ -589,12 +556,12 @@ void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr)
void sysfs_remove_file_from_group(struct kobject *kobj,
const struct attribute *attr, const char *group)
{
- struct dentry *dir;
+ struct sysfs_dirent *dir_sd;
- dir = lookup_one_len(group, kobj->dentry, strlen(group));
- if (!IS_ERR(dir)) {
- sysfs_hash_and_remove(dir, attr->name);
- dput(dir);
+ dir_sd = sysfs_get_dirent(kobj->sd, group);
+ if (dir_sd) {
+ sysfs_hash_and_remove(dir_sd, attr->name);
+ sysfs_put(dir_sd);
}
}
EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);
diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c
index 52eed2a7a5e..f318b73c790 100644
--- a/fs/sysfs/group.c
+++ b/fs/sysfs/group.c
@@ -18,26 +18,25 @@
#include "sysfs.h"
-static void remove_files(struct dentry * dir,
- const struct attribute_group * grp)
+static void remove_files(struct sysfs_dirent *dir_sd,
+ const struct attribute_group *grp)
{
struct attribute *const* attr;
for (attr = grp->attrs; *attr; attr++)
- sysfs_hash_and_remove(dir,(*attr)->name);
+ sysfs_hash_and_remove(dir_sd, (*attr)->name);
}
-static int create_files(struct dentry * dir,
- const struct attribute_group * grp)
+static int create_files(struct sysfs_dirent *dir_sd,
+ const struct attribute_group *grp)
{
struct attribute *const* attr;
int error = 0;
- for (attr = grp->attrs; *attr && !error; attr++) {
- error = sysfs_add_file(dir, *attr, SYSFS_KOBJ_ATTR);
- }
+ for (attr = grp->attrs; *attr && !error; attr++)
+ error = sysfs_add_file(dir_sd, *attr, SYSFS_KOBJ_ATTR);
if (error)
- remove_files(dir,grp);
+ remove_files(dir_sd, grp);
return error;
}
@@ -45,44 +44,44 @@ static int create_files(struct dentry * dir,
int sysfs_create_group(struct kobject * kobj,
const struct attribute_group * grp)
{
- struct dentry * dir;
+ struct sysfs_dirent *sd;
int error;
- BUG_ON(!kobj || !kobj->dentry);
+ BUG_ON(!kobj || !kobj->sd);
if (grp->name) {
- error = sysfs_create_subdir(kobj,grp->name,&dir);
+ error = sysfs_create_subdir(kobj, grp->name, &sd);
if (error)
return error;
} else
- dir = kobj->dentry;
- dir = dget(dir);
- if ((error = create_files(dir,grp))) {
+ sd = kobj->sd;
+ sysfs_get(sd);
+ error = create_files(sd, grp);
+ if (error) {
if (grp->name)
- sysfs_remove_subdir(dir);
+ sysfs_remove_subdir(sd);
}
- dput(dir);
+ sysfs_put(sd);
return error;
}
void sysfs_remove_group(struct kobject * kobj,
const struct attribute_group * grp)
{
- struct dentry * dir;
+ struct sysfs_dirent *dir_sd = kobj->sd;
+ struct sysfs_dirent *sd;
if (grp->name) {
- dir = lookup_one_len_kern(grp->name, kobj->dentry,
- strlen(grp->name));
- BUG_ON(IS_ERR(dir));
- }
- else
- dir = dget(kobj->dentry);
+ sd = sysfs_get_dirent(dir_sd, grp->name);
+ BUG_ON(!sd);
+ } else
+ sd = sysfs_get(dir_sd);
- remove_files(dir,grp);
+ remove_files(sd, grp);
if (grp->name)
- sysfs_remove_subdir(dir);
- /* release the ref. taken in this routine */
- dput(dir);
+ sysfs_remove_subdir(sd);
+
+ sysfs_put(sd);
}
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index 5266eec15f6..3756e152285 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -133,187 +133,94 @@ static inline void set_inode_attr(struct inode * inode, struct iattr * iattr)
*/
static struct lock_class_key sysfs_inode_imutex_key;
-struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent * sd)
+void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode)
{
- struct inode * inode = new_inode(sysfs_sb);
- if (inode) {
- inode->i_blocks = 0;
- inode->i_mapping->a_ops = &sysfs_aops;
- inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
- inode->i_op = &sysfs_inode_operations;
- inode->i_ino = sd->s_ino;
- lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key);
-
- if (sd->s_iattr) {
- /* sysfs_dirent has non-default attributes
- * get them for the new inode from persistent copy
- * in sysfs_dirent
- */
- set_inode_attr(inode, sd->s_iattr);
- } else
- set_default_inode_attr(inode, mode);
- }
- return inode;
-}
-
-int sysfs_create(struct dentry * dentry, int mode, int (*init)(struct inode *))
-{
- int error = 0;
- struct inode * inode = NULL;
- if (dentry) {
- if (!dentry->d_inode) {
- struct sysfs_dirent * sd = dentry->d_fsdata;
- if ((inode = sysfs_new_inode(mode, sd))) {
- if (dentry->d_parent && dentry->d_parent->d_inode) {
- struct inode *p_inode = dentry->d_parent->d_inode;
- p_inode->i_mtime = p_inode->i_ctime = CURRENT_TIME;
- }
- goto Proceed;
- }
- else
- error = -ENOMEM;
- } else
- error = -EEXIST;
- } else
- error = -ENOENT;
- goto Done;
-
- Proceed:
- if (init)
- error = init(inode);
- if (!error) {
- d_instantiate(dentry, inode);
- if (S_ISDIR(mode))
- dget(dentry); /* pin only directory dentry in core */
+ inode->i_blocks = 0;
+ inode->i_mapping->a_ops = &sysfs_aops;
+ inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
+ inode->i_op = &sysfs_inode_operations;
+ inode->i_ino = sd->s_ino;
+ lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key);
+
+ if (sd->s_iattr) {
+ /* sysfs_dirent has non-default attributes
+ * get them for the new inode from persistent copy
+ * in sysfs_dirent
+ */
+ set_inode_attr(inode, sd->s_iattr);
} else
- iput(inode);
- Done:
- return error;
+ set_default_inode_attr(inode, sd->s_mode);
}
-/*
- * Get the name for corresponding element represented by the given sysfs_dirent
+/**
+ * sysfs_get_inode - get inode for sysfs_dirent
+ * @sd: sysfs_dirent to allocate inode for
+ *
+ * Get inode for @sd. If such inode doesn't exist, a new inode
+ * is allocated and basics are initialized. New inode is
+ * returned locked.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * Pointer to allocated inode on success, NULL on failure.
*/
-const unsigned char * sysfs_get_name(struct sysfs_dirent *sd)
+struct inode * sysfs_get_inode(struct sysfs_dirent *sd)
{
- struct attribute * attr;
- struct bin_attribute * bin_attr;
- struct sysfs_symlink * sl;
-
- BUG_ON(!sd || !sd->s_element);
-
- switch (sd->s_type) {
- case SYSFS_DIR:
- /* Always have a dentry so use that */
- return sd->s_dentry->d_name.name;
-
- case SYSFS_KOBJ_ATTR:
- attr = sd->s_element;
- return attr->name;
-
- case SYSFS_KOBJ_BIN_ATTR:
- bin_attr = sd->s_element;
- return bin_attr->attr.name;
+ struct inode *inode;
- case SYSFS_KOBJ_LINK:
- sl = sd->s_element;
- return sl->link_name;
- }
- return NULL;
-}
+ inode = iget_locked(sysfs_sb, sd->s_ino);
+ if (inode && (inode->i_state & I_NEW))
+ sysfs_init_inode(sd, inode);
-static inline void orphan_all_buffers(struct inode *node)
-{
- struct sysfs_buffer_collection *set;
- struct sysfs_buffer *buf;
-
- mutex_lock_nested(&node->i_mutex, I_MUTEX_CHILD);
- set = node->i_private;
- if (set) {
- list_for_each_entry(buf, &set->associates, associates) {
- down(&buf->sem);
- buf->orphaned = 1;
- up(&buf->sem);
- }
- }
- mutex_unlock(&node->i_mutex);
+ return inode;
}
-
-/*
- * Unhashes the dentry corresponding to given sysfs_dirent
- * Called with parent inode's i_mutex held.
+/**
+ * sysfs_instantiate - instantiate dentry
+ * @dentry: dentry to be instantiated
+ * @inode: inode associated with @sd
+ *
+ * Unlock @inode if locked and instantiate @dentry with @inode.
+ *
+ * LOCKING:
+ * None.
*/
-void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent)
+void sysfs_instantiate(struct dentry *dentry, struct inode *inode)
{
- struct dentry *dentry = NULL;
- struct inode *inode;
+ BUG_ON(!dentry || dentry->d_inode);
- /* We're not holding a reference to ->s_dentry dentry but the
- * field will stay valid as long as sysfs_lock is held.
- */
- spin_lock(&sysfs_lock);
- spin_lock(&dcache_lock);
-
- /* dget dentry if it's still alive */
- if (sd->s_dentry && sd->s_dentry->d_inode)
- dentry = dget_locked(sd->s_dentry);
-
- spin_unlock(&dcache_lock);
- spin_unlock(&sysfs_lock);
-
- /* drop dentry */
- if (dentry) {
- spin_lock(&dcache_lock);
- spin_lock(&dentry->d_lock);
- if (!d_unhashed(dentry) && dentry->d_inode) {
- inode = dentry->d_inode;
- spin_lock(&inode->i_lock);
- __iget(inode);
- spin_unlock(&inode->i_lock);
- dget_locked(dentry);
- __d_drop(dentry);
- spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
- simple_unlink(parent->d_inode, dentry);
- orphan_all_buffers(inode);
- iput(inode);
- } else {
- spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
- }
+ if (inode->i_state & I_NEW)
+ unlock_new_inode(inode);
- dput(dentry);
- }
+ d_instantiate(dentry, inode);
}
-int sysfs_hash_and_remove(struct dentry * dir, const char * name)
+int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name)
{
- struct sysfs_dirent * sd;
- struct sysfs_dirent * parent_sd;
- int found = 0;
+ struct sysfs_addrm_cxt acxt;
+ struct sysfs_dirent **pos, *sd;
- if (!dir)
+ if (!dir_sd)
return -ENOENT;
- if (dir->d_inode == NULL)
- /* no inode means this hasn't been made visible yet */
- return -ENOENT;
+ sysfs_addrm_start(&acxt, dir_sd);
+
+ for (pos = &dir_sd->s_children; *pos; pos = &(*pos)->s_sibling) {
+ sd = *pos;
- parent_sd = dir->d_fsdata;
- mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
- list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
- if (!sd->s_element)
+ if (!sysfs_type(sd))
continue;
- if (!strcmp(sysfs_get_name(sd), name)) {
- list_del_init(&sd->s_sibling);
- sysfs_drop_dentry(sd, dir);
- sysfs_put(sd);
- found = 1;
+ if (!strcmp(sd->s_name, name)) {
+ *pos = sd->s_sibling;
+ sd->s_sibling = NULL;
+ sysfs_remove_one(&acxt, sd);
break;
}
}
- mutex_unlock(&dir->d_inode->i_mutex);
- return found ? 0 : -ENOENT;
+ if (sysfs_addrm_finish(&acxt))
+ return 0;
+ return -ENOENT;
}
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index 00ab9125d39..402cc356203 100644
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -19,28 +19,18 @@ struct vfsmount *sysfs_mount;
struct super_block * sysfs_sb = NULL;
struct kmem_cache *sysfs_dir_cachep;
-static void sysfs_clear_inode(struct inode *inode);
-
static const struct super_operations sysfs_ops = {
.statfs = simple_statfs,
.drop_inode = sysfs_delete_inode,
- .clear_inode = sysfs_clear_inode,
};
-static struct sysfs_dirent sysfs_root = {
- .s_sibling = LIST_HEAD_INIT(sysfs_root.s_sibling),
- .s_children = LIST_HEAD_INIT(sysfs_root.s_children),
- .s_element = NULL,
- .s_type = SYSFS_ROOT,
- .s_iattr = NULL,
+struct sysfs_dirent sysfs_root = {
+ .s_count = ATOMIC_INIT(1),
+ .s_flags = SYSFS_ROOT,
+ .s_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
.s_ino = 1,
};
-static void sysfs_clear_inode(struct inode *inode)
-{
- kfree(inode->i_private);
-}
-
static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
{
struct inode *inode;
@@ -53,24 +43,26 @@ static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
sb->s_time_gran = 1;
sysfs_sb = sb;
- inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
- &sysfs_root);
- if (inode) {
- inode->i_op = &sysfs_dir_inode_operations;
- inode->i_fop = &sysfs_dir_operations;
- /* directory inodes start off with i_nlink == 2 (for "." entry) */
- inc_nlink(inode);
- } else {
+ inode = new_inode(sysfs_sb);
+ if (!inode) {
pr_debug("sysfs: could not get root inode\n");
return -ENOMEM;
}
+ sysfs_init_inode(&sysfs_root, inode);
+
+ inode->i_op = &sysfs_dir_inode_operations;
+ inode->i_fop = &sysfs_dir_operations;
+ /* directory inodes start off with i_nlink == 2 (for "." entry) */
+ inc_nlink(inode);
+
root = d_alloc_root(inode);
if (!root) {
pr_debug("%s: could not get root dentry!\n",__FUNCTION__);
iput(inode);
return -ENOMEM;
}
+ sysfs_root.s_dentry = root;
root->d_fsdata = &sysfs_root;
sb->s_root = root;
return 0;
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index 7b9c5bfde92..2f86e042229 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -11,71 +11,39 @@
#include "sysfs.h"
-static int object_depth(struct kobject * kobj)
+static int object_depth(struct sysfs_dirent *sd)
{
- struct kobject * p = kobj;
int depth = 0;
- do { depth++; } while ((p = p->parent));
+
+ for (; sd->s_parent; sd = sd->s_parent)
+ depth++;
+
return depth;
}
-static int object_path_length(struct kobject * kobj)
+static int object_path_length(struct sysfs_dirent * sd)
{
- struct kobject * p = kobj;
int length = 1;
- do {
- length += strlen(kobject_name(p)) + 1;
- p = p->parent;
- } while (p);
+
+ for (; sd->s_parent; sd = sd->s_parent)
+ length += strlen(sd->s_name) + 1;
+
return length;
}
-static void fill_object_path(struct kobject * kobj, char * buffer, int length)
+static void fill_object_path(struct sysfs_dirent *sd, char *buffer, int length)
{
- struct kobject * p;
-
--length;
- for (p = kobj; p; p = p->parent) {
- int cur = strlen(kobject_name(p));
+ for (; sd->s_parent; sd = sd->s_parent) {
+ int cur = strlen(sd->s_name);
/* back up enough to print this bus id with '/' */
length -= cur;
- strncpy(buffer + length,kobject_name(p),cur);
+ strncpy(buffer + length, sd->s_name, cur);
*(buffer + --length) = '/';
}
}
-static int sysfs_add_link(struct dentry * parent, const char * name, struct kobject * target)
-{
- struct sysfs_dirent * parent_sd = parent->d_fsdata;
- struct sysfs_symlink * sl;
- int error = 0;
-
- error = -ENOMEM;
- sl = kmalloc(sizeof(*sl), GFP_KERNEL);
- if (!sl)
- goto exit1;
-
- sl->link_name = kmalloc(strlen(name) + 1, GFP_KERNEL);
- if (!sl->link_name)
- goto exit2;
-
- strcpy(sl->link_name, name);
- sl->target_kobj = kobject_get(target);
-
- error = sysfs_make_dirent(parent_sd, NULL, sl, S_IFLNK|S_IRWXUGO,
- SYSFS_KOBJ_LINK);
- if (!error)
- return 0;
-
- kobject_put(target);
- kfree(sl->link_name);
-exit2:
- kfree(sl);
-exit1:
- return error;
-}
-
/**
* sysfs_create_link - create symlink between two objects.
* @kobj: object whose directory we're creating the link in.
@@ -84,24 +52,57 @@ exit1:
*/
int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char * name)
{
- struct dentry *dentry = NULL;
- int error = -EEXIST;
+ struct sysfs_dirent *parent_sd = NULL;
+ struct sysfs_dirent *target_sd = NULL;
+ struct sysfs_dirent *sd = NULL;
+ struct sysfs_addrm_cxt acxt;
+ int error;
BUG_ON(!name);
if (!kobj) {
if (sysfs_mount && sysfs_mount->mnt_sb)
- dentry = sysfs_mount->mnt_sb->s_root;
+ parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata;
} else
- dentry = kobj->dentry;
+ parent_sd = kobj->sd;
+
+ error = -EFAULT;
+ if (!parent_sd)
+ goto out_put;
+
+ /* target->sd can go away beneath us but is protected with
+ * sysfs_assoc_lock. Fetch target_sd from it.
+ */
+ spin_lock(&sysfs_assoc_lock);
+ if (target->sd)
+ target_sd = sysfs_get(target->sd);
+ spin_unlock(&sysfs_assoc_lock);
+
+ error = -ENOENT;
+ if (!target_sd)
+ goto out_put;
+
+ error = -ENOMEM;
+ sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK);
+ if (!sd)
+ goto out_put;
+ sd->s_elem.symlink.target_sd = target_sd;
- if (!dentry)
- return -EFAULT;
+ sysfs_addrm_start(&acxt, parent_sd);
- mutex_lock(&dentry->d_inode->i_mutex);
- if (!sysfs_dirent_exist(dentry->d_fsdata, name))
- error = sysfs_add_link(dentry, name, target);
- mutex_unlock(&dentry->d_inode->i_mutex);
+ if (!sysfs_find_dirent(parent_sd, name)) {
+ sysfs_add_one(&acxt, sd);
+ sysfs_link_sibling(sd);
+ }
+
+ if (sysfs_addrm_finish(&acxt))
+ return 0;
+
+ error = -EEXIST;
+ /* fall through */
+ out_put:
+ sysfs_put(target_sd);
+ sysfs_put(sd);
return error;
}
@@ -114,17 +115,17 @@ int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char
void sysfs_remove_link(struct kobject * kobj, const char * name)
{
- sysfs_hash_and_remove(kobj->dentry,name);
+ sysfs_hash_and_remove(kobj->sd, name);
}
-static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target,
- char *path)
+static int sysfs_get_target_path(struct sysfs_dirent * parent_sd,
+ struct sysfs_dirent * target_sd, char *path)
{
char * s;
int depth, size;
- depth = object_depth(kobj);
- size = object_path_length(target) + depth * 3 - 1;
+ depth = object_depth(parent_sd);
+ size = object_path_length(target_sd) + depth * 3 - 1;
if (size > PATH_MAX)
return -ENAMETOOLONG;
@@ -133,7 +134,7 @@ static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target,
for (s = path; depth--; s += 3)
strcpy(s,"../");
- fill_object_path(target, path, size);
+ fill_object_path(target_sd, path, size);
pr_debug("%s: path = '%s'\n", __FUNCTION__, path);
return 0;
@@ -141,27 +142,16 @@ static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target,
static int sysfs_getlink(struct dentry *dentry, char * path)
{
- struct kobject *kobj, *target_kobj;
- int error = 0;
+ struct sysfs_dirent *sd = dentry->d_fsdata;
+ struct sysfs_dirent *parent_sd = sd->s_parent;
+ struct sysfs_dirent *target_sd = sd->s_elem.symlink.target_sd;
+ int error;
- kobj = sysfs_get_kobject(dentry->d_parent);
- if (!kobj)
- return -EINVAL;
+ mutex_lock(&sysfs_mutex);
+ error = sysfs_get_target_path(parent_sd, target_sd, path);
+ mutex_unlock(&sysfs_mutex);
- target_kobj = sysfs_get_kobject(dentry);
- if (!target_kobj) {
- kobject_put(kobj);
- return -EINVAL;
- }
-
- down_read(&sysfs_rename_sem);
- error = sysfs_get_target_path(kobj, target_kobj, path);
- up_read(&sysfs_rename_sem);
-
- kobject_put(kobj);
- kobject_put(target_kobj);
return error;
-
}
static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 502c949c402..6a37f2386a8 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -1,9 +1,40 @@
+struct sysfs_elem_dir {
+ struct kobject * kobj;
+};
+
+struct sysfs_elem_symlink {
+ struct sysfs_dirent * target_sd;
+};
+
+struct sysfs_elem_attr {
+ struct attribute * attr;
+};
+
+struct sysfs_elem_bin_attr {
+ struct bin_attribute * bin_attr;
+};
+
+/*
+ * As long as s_count reference is held, the sysfs_dirent itself is
+ * accessible. Dereferencing s_elem or any other outer entity
+ * requires s_active reference.
+ */
struct sysfs_dirent {
atomic_t s_count;
- struct list_head s_sibling;
- struct list_head s_children;
- void * s_element;
- int s_type;
+ atomic_t s_active;
+ struct sysfs_dirent * s_parent;
+ struct sysfs_dirent * s_sibling;
+ struct sysfs_dirent * s_children;
+ const char * s_name;
+
+ union {
+ struct sysfs_elem_dir dir;
+ struct sysfs_elem_symlink symlink;
+ struct sysfs_elem_attr attr;
+ struct sysfs_elem_bin_attr bin_attr;
+ } s_elem;
+
+ unsigned int s_flags;
umode_t s_mode;
ino_t s_ino;
struct dentry * s_dentry;
@@ -11,30 +42,60 @@ struct sysfs_dirent {
atomic_t s_event;
};
+#define SD_DEACTIVATED_BIAS INT_MIN
+
+struct sysfs_addrm_cxt {
+ struct sysfs_dirent *parent_sd;
+ struct inode *parent_inode;
+ struct sysfs_dirent *removed;
+ int cnt;
+};
+
extern struct vfsmount * sysfs_mount;
+extern struct sysfs_dirent sysfs_root;
extern struct kmem_cache *sysfs_dir_cachep;
-extern void sysfs_delete_inode(struct inode *inode);
-extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *);
-extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
+extern struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
+extern void sysfs_link_sibling(struct sysfs_dirent *sd);
+extern void sysfs_unlink_sibling(struct sysfs_dirent *sd);
+extern struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd);
+extern void sysfs_put_active(struct sysfs_dirent *sd);
+extern struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd);
+extern void sysfs_put_active_two(struct sysfs_dirent *sd);
+extern void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
+ struct sysfs_dirent *parent_sd);
+extern void sysfs_add_one(struct sysfs_addrm_cxt *acxt,
+ struct sysfs_dirent *sd);
+extern void sysfs_remove_one(struct sysfs_addrm_cxt *acxt,
+ struct sysfs_dirent *sd);
+extern int sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
-extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *);
-extern int sysfs_make_dirent(struct sysfs_dirent *, struct dentry *, void *,
- umode_t, int);
-
-extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
-extern int sysfs_hash_and_remove(struct dentry * dir, const char * name);
+extern void sysfs_delete_inode(struct inode *inode);
+extern void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode);
+extern struct inode * sysfs_get_inode(struct sysfs_dirent *sd);
+extern void sysfs_instantiate(struct dentry *dentry, struct inode *inode);
+
+extern void release_sysfs_dirent(struct sysfs_dirent * sd);
+extern struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
+ const unsigned char *name);
+extern struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
+ const unsigned char *name);
+extern struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode,
+ int type);
+
+extern int sysfs_add_file(struct sysfs_dirent *dir_sd,
+ const struct attribute *attr, int type);
+extern int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);
-extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);
-extern void sysfs_remove_subdir(struct dentry *);
+extern int sysfs_create_subdir(struct kobject *kobj, const char *name,
+ struct sysfs_dirent **p_sd);
+extern void sysfs_remove_subdir(struct sysfs_dirent *sd);
-extern const unsigned char * sysfs_get_name(struct sysfs_dirent *sd);
-extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent);
extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
-extern spinlock_t sysfs_lock;
-extern struct rw_semaphore sysfs_rename_sem;
+extern spinlock_t sysfs_assoc_lock;
+extern struct mutex sysfs_mutex;
extern struct super_block * sysfs_sb;
extern const struct file_operations sysfs_dir_operations;
extern const struct file_operations sysfs_file_operations;
@@ -42,73 +103,9 @@ extern const struct file_operations bin_fops;
extern const struct inode_operations sysfs_dir_inode_operations;
extern const struct inode_operations sysfs_symlink_inode_operations;
-struct sysfs_symlink {
- char * link_name;
- struct kobject * target_kobj;
-};
-
-struct sysfs_buffer {
- struct list_head associates;
- size_t count;
- loff_t pos;
- char * page;
- struct sysfs_ops * ops;
- struct semaphore sem;
- int orphaned;
- int needs_read_fill;
- int event;
-};
-
-struct sysfs_buffer_collection {
- struct list_head associates;
-};
-
-static inline struct kobject * to_kobj(struct dentry * dentry)
-{
- struct sysfs_dirent * sd = dentry->d_fsdata;
- return ((struct kobject *) sd->s_element);
-}
-
-static inline struct attribute * to_attr(struct dentry * dentry)
+static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
{
- struct sysfs_dirent * sd = dentry->d_fsdata;
- return ((struct attribute *) sd->s_element);
-}
-
-static inline struct bin_attribute * to_bin_attr(struct dentry * dentry)
-{
- struct sysfs_dirent * sd = dentry->d_fsdata;
- return ((struct bin_attribute *) sd->s_element);
-}
-
-static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)
-{
- struct kobject * kobj = NULL;
-
- spin_lock(&dcache_lock);
- if (!d_unhashed(dentry)) {
- struct sysfs_dirent * sd = dentry->d_fsdata;
- if (sd->s_type & SYSFS_KOBJ_LINK) {
- struct sysfs_symlink * sl = sd->s_element;
- kobj = kobject_get(sl->target_kobj);
- } else
- kobj = kobject_get(sd->s_element);
- }
- spin_unlock(&dcache_lock);
-
- return kobj;
-}
-
-static inline void release_sysfs_dirent(struct sysfs_dirent * sd)
-{
- if (sd->s_type & SYSFS_KOBJ_LINK) {
- struct sysfs_symlink * sl = sd->s_element;
- kfree(sl->link_name);
- kobject_put(sl->target_kobj);
- kfree(sl);
- }
- kfree(sd->s_iattr);
- kmem_cache_free(sysfs_dir_cachep, sd);
+ return sd->s_flags & SYSFS_TYPE_MASK;
}
static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
@@ -122,7 +119,7 @@ static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
static inline void sysfs_put(struct sysfs_dirent * sd)
{
- if (atomic_dec_and_test(&sd->s_count))
+ if (sd && atomic_dec_and_test(&sd->s_count))
release_sysfs_dirent(sd);
}