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-rw-r--r--fs/sysfs/bin.c13
-rw-r--r--fs/sysfs/dir.c12
-rw-r--r--fs/sysfs/inode.c26
-rw-r--r--fs/sysfs/symlink.c14
-rw-r--r--fs/sysfs/sysfs.h2
5 files changed, 47 insertions, 20 deletions
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index c16a93c353c..98022e41cda 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -10,6 +10,7 @@
#include <linux/errno.h>
#include <linux/fs.h>
+#include <linux/kernel.h>
#include <linux/kobject.h>
#include <linux/module.h>
#include <linux/slab.h>
@@ -176,7 +177,6 @@ const struct file_operations bin_fops = {
* sysfs_create_bin_file - create binary file for object.
* @kobj: object.
* @attr: attribute descriptor.
- *
*/
int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
@@ -191,13 +191,16 @@ int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
* sysfs_remove_bin_file - remove binary file for object.
* @kobj: object.
* @attr: attribute descriptor.
- *
*/
-int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
+void sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
{
- sysfs_hash_and_remove(kobj->dentry,attr->attr.name);
- return 0;
+ if (sysfs_hash_and_remove(kobj->dentry, attr->attr.name) < 0) {
+ printk(KERN_ERR "%s: "
+ "bad dentry or inode or no such file: \"%s\"\n",
+ __FUNCTION__, attr->attr.name);
+ dump_stack();
+ }
}
EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 610b5bdbe75..5f3d725d112 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -43,7 +43,7 @@ static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent * parent_sd,
memset(sd, 0, sizeof(*sd));
atomic_set(&sd->s_count, 1);
- atomic_set(&sd->s_event, 0);
+ atomic_set(&sd->s_event, 1);
INIT_LIST_HEAD(&sd->s_children);
list_add(&sd->s_sibling, &parent_sd->s_children);
sd->s_element = element;
@@ -430,10 +430,9 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
i++;
/* fallthrough */
default:
- if (filp->f_pos == 2) {
- list_del(q);
- list_add(q, &parent_sd->s_children);
- }
+ if (filp->f_pos == 2)
+ list_move(q, &parent_sd->s_children);
+
for (p=q->next; p!= &parent_sd->s_children; p=p->next) {
struct sysfs_dirent *next;
const char * name;
@@ -455,8 +454,7 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
dt_type(next)) < 0)
return 0;
- list_del(q);
- list_add(q, p);
+ list_move(q, p);
p = q;
filp->f_pos++;
}
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index f0b347bd12c..e79e38d52c0 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -12,11 +12,12 @@
#include <linux/namei.h>
#include <linux/backing-dev.h>
#include <linux/capability.h>
+#include <linux/errno.h>
#include "sysfs.h"
extern struct super_block * sysfs_sb;
-static struct address_space_operations sysfs_aops = {
+static const struct address_space_operations sysfs_aops = {
.readpage = simple_readpage,
.prepare_write = simple_prepare_write,
.commit_write = simple_commit_write
@@ -109,15 +110,26 @@ static inline void set_inode_attr(struct inode * inode, struct iattr * iattr)
inode->i_ctime = iattr->ia_ctime;
}
+
+/*
+ * sysfs has a different i_mutex lock order behavior for i_mutex than other
+ * filesystems; sysfs i_mutex is called in many places with subsystem locks
+ * held. At the same time, many of the VFS locking rules do not apply to
+ * sysfs at all (cross directory rename for example). To untangle this mess
+ * (which gives false positives in lockdep), we're giving sysfs inodes their
+ * own class for i_mutex.
+ */
+static struct lock_class_key sysfs_inode_imutex_key;
+
struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent * sd)
{
struct inode * inode = new_inode(sysfs_sb);
if (inode) {
- inode->i_blksize = PAGE_CACHE_SIZE;
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;
+ lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key);
if (sd->s_iattr) {
/* sysfs_dirent has non-default attributes
@@ -222,17 +234,18 @@ void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent)
}
}
-void sysfs_hash_and_remove(struct dentry * dir, const char * name)
+int sysfs_hash_and_remove(struct dentry * dir, const char * name)
{
struct sysfs_dirent * sd;
struct sysfs_dirent * parent_sd;
+ int found = 0;
if (!dir)
- return;
+ return -ENOENT;
if (dir->d_inode == NULL)
/* no inode means this hasn't been made visible yet */
- return;
+ return -ENOENT;
parent_sd = dir->d_fsdata;
mutex_lock(&dir->d_inode->i_mutex);
@@ -243,8 +256,11 @@ void sysfs_hash_and_remove(struct dentry * dir, const char * name)
list_del_init(&sd->s_sibling);
sysfs_drop_dentry(sd, dir);
sysfs_put(sd);
+ found = 1;
break;
}
}
mutex_unlock(&dir->d_inode->i_mutex);
+
+ return found ? 0 : -ENOENT;
}
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index d2eac3ceed5..f50e3cc2ded 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -3,6 +3,7 @@
*/
#include <linux/fs.h>
+#include <linux/mount.h>
#include <linux/module.h>
#include <linux/kobject.h>
#include <linux/namei.h>
@@ -82,10 +83,19 @@ exit1:
*/
int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char * name)
{
- struct dentry * dentry = kobj->dentry;
+ struct dentry *dentry = NULL;
int error = -EEXIST;
- BUG_ON(!kobj || !kobj->dentry || !name);
+ BUG_ON(!name);
+
+ if (!kobj) {
+ if (sysfs_mount && sysfs_mount->mnt_sb)
+ dentry = sysfs_mount->mnt_sb->s_root;
+ } else
+ dentry = kobj->dentry;
+
+ if (!dentry)
+ return -EFAULT;
mutex_lock(&dentry->d_inode->i_mutex);
if (!sysfs_dirent_exist(dentry->d_fsdata, name))
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 3651ffb5ec0..6f3d6bd5288 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -10,7 +10,7 @@ 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 void sysfs_hash_and_remove(struct dentry * dir, const char * name);
+extern int sysfs_hash_and_remove(struct dentry * dir, 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 **);