GFS2: Post-VFS scale update for RCU path walk

We can allow a few more cases to use RCU path walking than
originally allowed. It should be possible to also enable
RCU path walking when the glock is already cached. Thats
a bit more complicated though, so left for a future patch.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Nick Piggin <npiggin@gmail.com>
This commit is contained in:
Steven Whitehouse 2011-01-19 09:42:40 +00:00
parent bc015cb841
commit 75d5cfbe4b
2 changed files with 10 additions and 7 deletions

View file

@ -80,8 +80,11 @@ int gfs2_check_acl(struct inode *inode, int mask, unsigned int flags)
struct posix_acl *acl;
int error;
if (flags & IPERM_FLAG_RCU)
return -ECHILD;
if (flags & IPERM_FLAG_RCU) {
if (!negative_cached_acl(inode, ACL_TYPE_ACCESS))
return -ECHILD;
return -EAGAIN;
}
acl = gfs2_acl_get(GFS2_I(inode), ACL_TYPE_ACCESS);
if (IS_ERR(acl))

View file

@ -1026,9 +1026,9 @@ static void gfs2_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
/**
* gfs2_permission -
* @inode:
* @mask:
* @nd: passed from Linux VFS, ignored by us
* @inode: The inode
* @mask: The mask to be tested
* @flags: Indicates whether this is an RCU path walk or not
*
* This may be called from the VFS directly, or from within GFS2 with the
* inode locked, so we look to see if the glock is already locked and only
@ -1044,11 +1044,11 @@ int gfs2_permission(struct inode *inode, int mask, unsigned int flags)
int error;
int unlock = 0;
if (flags & IPERM_FLAG_RCU)
return -ECHILD;
ip = GFS2_I(inode);
if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
if (flags & IPERM_FLAG_RCU)
return -ECHILD;
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
if (error)
return error;