From 7d8cb26d7dcb911f110b7762bd5941e8f009d6c3 Mon Sep 17 00:00:00 2001 From: Sage Weil Date: Tue, 24 Aug 2010 08:44:16 -0700 Subject: ceph: maintain i_head_snapc when any caps are dirty, not just for data We used to use i_head_snapc to keep track of which snapc the current epoch of dirty data was dirtied under. It is used by queue_cap_snap to set up the cap_snap. However, since we queue cap snaps for any dirty caps, not just for dirty file data, we need to keep a valid i_head_snapc anytime we have dirty|flushing caps. This fixes a NULL pointer deref in queue_cap_snap when writing back dirty caps without data (e.g., snaptest-authwb.sh). Signed-off-by: Sage Weil --- fs/ceph/addr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/ceph/addr.c') diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 420d46974ec..4cfce1ee31f 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -87,7 +87,7 @@ static int ceph_set_page_dirty(struct page *page) /* dirty the head */ spin_lock(&inode->i_lock); - if (ci->i_wrbuffer_ref_head == 0) + if (ci->i_head_snapc == NULL) ci->i_head_snapc = ceph_get_snap_context(snapc); ++ci->i_wrbuffer_ref_head; if (ci->i_wrbuffer_ref == 0) @@ -346,7 +346,7 @@ static struct ceph_snap_context *get_oldest_context(struct inode *inode, break; } } - if (!snapc && ci->i_head_snapc) { + if (!snapc && ci->i_wrbuffer_ref_head) { snapc = ceph_get_snap_context(ci->i_head_snapc); dout(" head snapc %p has %d dirty pages\n", snapc, ci->i_wrbuffer_ref_head); -- cgit v1.2.3