[PATCH] 9p: fix segfault caused by race condition in meta-data operations

Running dbench multithreaded exposed a race condition where fid structures
were removed while in use.  This patch adds semaphores to meta-data operations
to protect the fid structure.  Some cleanup of error-case handling in the
inode operations is also included.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Eric Van Hensbergen
2007-01-26 00:57:06 -08:00
committed by Linus Torvalds
parent ff76e1dfc8
commit da977b2c7e
4 changed files with 196 additions and 129 deletions
+5
View File
@@ -30,6 +30,8 @@ struct v9fs_fid {
struct list_head list; /* list of fids associated with a dentry */
struct list_head active; /* XXX - debug */
struct semaphore lock;
u32 fid;
unsigned char fidopen; /* set when fid is opened */
unsigned char fidclunked; /* set when fid has already been clunked */
@@ -55,3 +57,6 @@ struct v9fs_fid *v9fs_fid_get_created(struct dentry *);
void v9fs_fid_destroy(struct v9fs_fid *fid);
struct v9fs_fid *v9fs_fid_create(struct v9fs_session_info *, int fid);
int v9fs_fid_insert(struct v9fs_fid *fid, struct dentry *dentry);
struct v9fs_fid *v9fs_fid_clone(struct dentry *dentry);
void v9fs_fid_clunk(struct v9fs_session_info *v9ses, struct v9fs_fid *fid);