nfsd: Push mnt_want_write() outside of i_mutex
When mnt_want_write() starts to handle freezing it will get a full lock
semantics requiring proper lock ordering. So push mnt_want_write() call
consistently outside of i_mutex.
CC: linux-nfs@vger.kernel.org
CC: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index ec0611b..359594c 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -110,12 +110,19 @@
static inline int fh_want_write(struct svc_fh *fh)
{
- return mnt_want_write(fh->fh_export->ex_path.mnt);
+ int ret = mnt_want_write(fh->fh_export->ex_path.mnt);
+
+ if (!ret)
+ fh->fh_want_write = 1;
+ return ret;
}
static inline void fh_drop_write(struct svc_fh *fh)
{
- mnt_drop_write(fh->fh_export->ex_path.mnt);
+ if (fh->fh_want_write) {
+ fh->fh_want_write = 0;
+ mnt_drop_write(fh->fh_export->ex_path.mnt);
+ }
}
#endif /* LINUX_NFSD_VFS_H */