[PATCH 21/23] vfs: Teach fsync to use file_hotplug_lock

Eric W. Biederman
2009-06-01T21:57:00Z

From: Eric W. Biederman <ebiederm@maxwell.aristanetworks.com>

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
---
fs/sync.c | 9 ++++++++-
1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/fs/sync.c b/fs/sync.c
index e9d56f6..ac6da60 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -197,6 +197,9 @@ int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
* don't have a struct file available. Damn nfsd..
*/
if (file) {
+ ret = -EIO;
+ if (!file_hotplug_read_trylock(file))
+ goto out;
mapping = file->f_mapping;
fop = file->f_op;
} else {
@@ -206,7 +209,7 @@ int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)

if (!fop || !fop->fsync) {
ret = -EINVAL;
- goto out;
+ goto out_unlock;
}

ret = filemap_fdatawrite(mapping);
@@ -223,6 +226,10 @@ int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
err = filemap_fdatawait(mapping);
if (!ret)
ret = err;
+
+out_unlock:
+ if (file)
+ file_hotplug_read_unlock(file);
out:
return ret;
}
--
1.6.3.1.54.g99dd.dirty