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 <[email protected]> Cc: Nick Piggin <[email protected]> diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c index 7118f1a..cbc0715 100644 --- a/fs/gfs2/acl.c +++ b/fs/gfs2/acl.c @@ -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)) diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c index d8b26ac..09e436a 100644 --- a/fs/gfs2/ops_inode.c +++ b/fs/gfs2/ops_inode.c @@ -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; -- 1.7.4
