GFS2: Prevent delete work from occurring on glocks used for create

This patch tries to prevent delete work (queued via iopen callback)
from executing if the glock is currently being used to create
a new inode.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 5788ebff716a..7f0257309b3e 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -572,6 +572,12 @@ static void delete_work_func(struct work_struct *work)
 	struct inode *inode;
 	u64 no_addr = gl->gl_name.ln_number;
 
+	/* If someone's using this glock to create a new dinode, the block must
+	   have been freed by another node, then re-used, in which case our
+	   iopen callback is too late after the fact. Ignore it. */
+	if (test_bit(GLF_INODE_CREATING, &gl->gl_flags))
+		goto out;
+
 	ip = gl->gl_object;
 	/* Note: Unsafe to dereference ip as we don't hold right refs/locks */
 
@@ -583,6 +589,7 @@ static void delete_work_func(struct work_struct *work)
 		d_prune_aliases(inode);
 		iput(inode);
 	}
+out:
 	gfs2_glock_put(gl);
 }