diff options
| -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 7dfcc3317490..499cff8554fc 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);  } | 
