[PATCH] v9fs: fix races in fid allocation
Fid management cleanup. The patch attempts to fix the races in dentry's
fid management.
Dentries don't keep the opened fids anymore, they are moved to the file
structs. Ideally there should be no more than one fid with fidcreate equal
to zero in the dentry's list of fids.
v9fs_fid_create initializes the important fields (fid, fidcreated) before
v9fs_fid is added to the list. v9fs_fid_lookup returns only fids that are
not created by v9fs_create. v9fs_fid_get_created returns the fid created
by the same process by v9fs_create (if any) and removes it from dentry's
list
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/9p/fid.h b/fs/9p/fid.h
index 7db478c..84c673a 100644
--- a/fs/9p/fid.h
+++ b/fs/9p/fid.h
@@ -25,6 +25,7 @@
#define FID_OP 0
#define FID_WALK 1
+#define FID_CREATE 2
struct v9fs_fid {
struct list_head list; /* list of fids associated with a dentry */
@@ -52,6 +53,8 @@
struct v9fs_session_info *v9ses; /* session info for this FID */
};
-struct v9fs_fid *v9fs_fid_lookup(struct dentry *dentry, int type);
+struct v9fs_fid *v9fs_fid_lookup(struct dentry *dentry);
+struct v9fs_fid *v9fs_fid_get_created(struct dentry *);
void v9fs_fid_destroy(struct v9fs_fid *fid);
-struct v9fs_fid *v9fs_fid_create(struct dentry *);
+struct v9fs_fid *v9fs_fid_create(struct dentry *,
+ struct v9fs_session_info *v9ses, int fid, int create);