diff options
author | Tejun Heo <htejun@gmail.com> | 2007-06-14 03:45:15 +0900 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-07-11 16:09:04 -0700 |
commit | aecdcedaab49ca40620dc7dd70f67ee7269a66c9 (patch) | |
tree | df1faa0302e6fb428b7ae0a14d443626fd73b121 | |
parent | 3e5190380ebef77f2b015c9e7a4ca225a3d75021 (diff) | |
download | op-kernel-dev-aecdcedaab49ca40620dc7dd70f67ee7269a66c9.zip op-kernel-dev-aecdcedaab49ca40620dc7dd70f67ee7269a66c9.tar.gz |
sysfs: implement kobj_sysfs_assoc_lock
kobj->dentry can go away anytime unless the user controls when the
associated sysfs node is deleted. This patch implements
kobj_sysfs_assoc_lock which protects kobj->dentry. This will be used
to maintain kobj based API when converting sysfs to use sysfs_dirent
tree instead of dentry/kobject.
Note that this lock belongs to kobject/driver-model not sysfs. Once
sysfs is converted to not use kobject in its interface, this can be
removed from sysfs.
This is in preparation of object reference simplification.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | fs/sysfs/dir.c | 8 | ||||
-rw-r--r-- | fs/sysfs/sysfs.h | 1 |
2 files changed, 8 insertions, 1 deletions
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 0791226..e9fddcc 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -15,6 +15,7 @@ DECLARE_RWSEM(sysfs_rename_sem); spinlock_t sysfs_lock = SPIN_LOCK_UNLOCKED; +spinlock_t kobj_sysfs_assoc_lock = SPIN_LOCK_UNLOCKED; static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED; static DEFINE_IDA(sysfs_ino_ida); @@ -426,8 +427,13 @@ static void __sysfs_remove_dir(struct dentry *dentry) void sysfs_remove_dir(struct kobject * kobj) { - __sysfs_remove_dir(kobj->dentry); + struct dentry *d = kobj->dentry; + + spin_lock(&kobj_sysfs_assoc_lock); kobj->dentry = NULL; + spin_unlock(&kobj_sysfs_assoc_lock); + + __sysfs_remove_dir(d); } int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent, diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index 39ab048..718e2e1 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -62,6 +62,7 @@ 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 spinlock_t kobj_sysfs_assoc_lock; extern struct rw_semaphore sysfs_rename_sem; extern struct super_block * sysfs_sb; extern const struct file_operations sysfs_dir_operations; |