[PATCH 01/12] ubd: untagle discard vs write zeroes not support handling

[Christoph Hellwig <hch@xxxxxx>]

Discard and Write Zeroes are different operation and implemented
by different fallocate opcodes for ubd.  If one fails the other one
can work and vice versa.

Split the code to disable the operations in ubd_handler to only
disable the operation that actually failed.

Fixes: 50109b5a03b4 ("um: Add support for DISCARD in the UBD Driver")
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 arch/um/drivers/ubd_kern.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index ef805eaa9e013d..a79a3b7c33a647 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -471,9 +471,14 @@ static void ubd_handler(void)
                for (count = 0; count < n/sizeof(struct io_thread_req *); 
count++) {
                        struct io_thread_req *io_req = (*irq_req_buffer)[count];
 
-                       if ((io_req->error == BLK_STS_NOTSUPP) && 
(req_op(io_req->req) == REQ_OP_DISCARD)) {
-                               blk_queue_max_discard_sectors(io_req->req->q, 
0);
-                               
blk_queue_max_write_zeroes_sectors(io_req->req->q, 0);
+                       if (io_req->error == BLK_STS_NOTSUPP) {
+                               struct request_queue *q = io_req->req->q;
+
+                               if (req_op(io_req->req) == REQ_OP_DISCARD)
+                                       blk_queue_max_discard_sectors(q, 0);
+                               if (req_op(io_req->req) == REQ_OP_WRITE_ZEROES)
+                                       blk_queue_max_write_zeroes_sectors(q,
+                                                       0);
                        }
                        blk_mq_end_request(io_req->req, io_req->error);
                        kfree(io_req);
-- 
2.43.0