[PATCH 4.4 27/80] fscache: Allow cancelled operations to be enqueued

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Kiran Kumar Modukuri <kiran.modukuri@xxxxxxxxx>

[ Upstream commit d0eb06afe712b7b103b6361f40a9a0c638524669 ]

Alter the state-check assertion in fscache_enqueue_operation() to allow
cancelled operations to be given processing time so they can be cleaned up.

Also fix a debugging statement that was requiring such operations to have
an object assigned.

Fixes: 9ae326a69004 ("CacheFiles: A cache that backs onto a mounted filesystem")
Reported-by: Kiran Kumar Modukuri <kiran.modukuri@xxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 fs/fscache/operation.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/fs/fscache/operation.c
+++ b/fs/fscache/operation.c
@@ -66,7 +66,8 @@ void fscache_enqueue_operation(struct fs
 	ASSERT(op->processor != NULL);
 	ASSERT(fscache_object_is_available(op->object));
 	ASSERTCMP(atomic_read(&op->usage), >, 0);
-	ASSERTCMP(op->state, ==, FSCACHE_OP_ST_IN_PROGRESS);
+	ASSERTIFCMP(op->state != FSCACHE_OP_ST_IN_PROGRESS,
+		    op->state, ==,  FSCACHE_OP_ST_CANCELLED);
 
 	fscache_stat(&fscache_n_op_enqueue);
 	switch (op->flags & FSCACHE_OP_TYPE) {
@@ -481,7 +482,8 @@ void fscache_put_operation(struct fscach
 	struct fscache_cache *cache;
 
 	_enter("{OBJ%x OP%x,%d}",
-	       op->object->debug_id, op->debug_id, atomic_read(&op->usage));
+	       op->object ? op->object->debug_id : 0,
+	       op->debug_id, atomic_read(&op->usage));
 
 	ASSERTCMP(atomic_read(&op->usage), >, 0);