diff options
Diffstat (limited to 'fs/sysfs')
| -rw-r--r-- | fs/sysfs/file.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 7dfcc331749..499cff8554f 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -25,15 +25,17 @@ #include "sysfs.h" /* - * There's one sysfs_buffer for each open file and one - * sysfs_open_dirent for each sysfs_dirent with one or more open - * files. + * There's one sysfs_buffer for each open file and one sysfs_open_dirent + * for each sysfs_dirent with one or more open files. * - * filp->private_data points to sysfs_buffer and - * sysfs_dirent->s_attr.open points to sysfs_open_dirent. s_attr.open - * is protected by sysfs_open_dirent_lock. + * sysfs_dirent->s_attr.open points to sysfs_open_dirent. s_attr.open is + * protected by sysfs_open_dirent_lock. + * + * filp->private_data points to sysfs_buffer which is chained at + * sysfs_open_dirent->buffers, which is protected by sysfs_open_file_mutex. */ static DEFINE_SPINLOCK(sysfs_open_dirent_lock); +static DEFINE_MUTEX(sysfs_open_file_mutex); struct sysfs_open_dirent { atomic_t refcnt; @@ -272,6 +274,7 @@ static int sysfs_get_open_dirent(struct sysfs_dirent *sd, struct sysfs_open_dirent *od, *new_od = NULL; retry: + mutex_lock(&sysfs_open_file_mutex); spin_lock_irq(&sysfs_open_dirent_lock); if (!sd->s_attr.open && new_od) { @@ -286,6 +289,7 @@ static int sysfs_get_open_dirent(struct sysfs_dirent *sd, } spin_unlock_irq(&sysfs_open_dirent_lock); + mutex_unlock(&sysfs_open_file_mutex); if (od) { kfree(new_od); @@ -321,6 +325,7 @@ static void sysfs_put_open_dirent(struct sysfs_dirent *sd, struct sysfs_open_dirent *od = sd->s_attr.open; unsigned long flags; + mutex_lock(&sysfs_open_file_mutex); spin_lock_irqsave(&sysfs_open_dirent_lock, flags); list_del(&buffer->list); @@ -330,6 +335,7 @@ static void sysfs_put_open_dirent(struct sysfs_dirent *sd, od = NULL; spin_unlock_irqrestore(&sysfs_open_dirent_lock, flags); + mutex_unlock(&sysfs_open_file_mutex); kfree(od); } |