[PATCH 6/9] sysfs: use check_submounts_and_drop()

From: Miklos Szeredi
Date: Thu Aug 08 2013 - 11:26:56 EST


From: Miklos Szeredi <mszeredi@xxxxxxx>

Do have_submounts(), shrink_dcache_parent() and d_drop() atomically.

check_submounts_and_drop() can deal with negative dentries and
non-directories as well.

Non-directories can also be mounted on. And just like directories we don't
want these to disappear with invalidation.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxx>
---
fs/sysfs/dir.c | 20 ++++++++------------
1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index e068e74..fde8856 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -297,7 +297,6 @@ static int sysfs_dentry_delete(const struct dentry *dentry)
static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags)
{
struct sysfs_dirent *sd;
- int is_dir;
int type;

if (flags & LOOKUP_RCU)
@@ -341,18 +340,15 @@ out_bad:
* is performed at its new name the dentry will be readded
* to the dcache hashes.
*/
- is_dir = (sysfs_type(sd) == SYSFS_DIR);
mutex_unlock(&sysfs_mutex);
- if (is_dir) {
- /* If we have submounts we must allow the vfs caches
- * to lie about the state of the filesystem to prevent
- * leaks and other nasty things.
- */
- if (have_submounts(dentry))
- goto out_valid;
- shrink_dcache_parent(dentry);
- }
- d_drop(dentry);
+
+ /* If we have submounts we must allow the vfs caches
+ * to lie about the state of the filesystem to prevent
+ * leaks and other nasty things.
+ */
+ if (check_submounts_and_drop(dentry) != 0)
+ goto out_valid;
+
return 0;
}

--
1.8.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/