qemu-kvm/kvm-block-Add-flags-parameter-to-blk_-_pdiscard.patch

From 9a2d6f97d94f24ad7bfc83aea06d3324cbd46424 Mon Sep 17 00:00:00 2001
From: Kevin Wolf <kwolf@redhat.com>
Date: Tue, 21 Apr 2026 18:11:28 +0200
Subject: [PATCH 03/52] block: Add flags parameter to blk_*_pdiscard()

RH-Author: Kevin Wolf <kwolf@redhat.com>
RH-MergeRequest: 503: ide: Fix deadlock between TRIM and drain
RH-Jira: RHEL-121686
RH-Acked-by: Hanna Czenczek <hreitz@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Commit: [3/7] 40ce25b1169cccc9c655eeb59827f8bf7daf75f4 (kmwolf/centos-qemu-kvm)

All existing callers pass 0, but we need a way to pass BDRV_REQ_NO_QUEUE
for discard requests.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20260421161132.99878-4-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 53074ba0330ae8831abbae2521c012e1d9072ed3)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/block-backend.c             | 11 ++++++-----
 block/export/virtio-blk-handler.c |  2 +-
 block/mirror.c                    |  4 ++--
 include/system/block-backend-io.h |  4 ++--
 nbd/server.c                      |  2 +-
 qemu-io-cmds.c                    |  2 +-
 tests/unit/test-block-iothread.c  |  4 ++--
 7 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/block/block-backend.c b/block/block-backend.c
index a0f4c841da..d97b26b743 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -1803,12 +1803,13 @@ BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
 
 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
 static int coroutine_fn
-blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes)
+blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes,
+                   BdrvRequestFlags flags)
 {
     int ret;
     IO_CODE();
 
-    blk_wait_while_drained(blk, 0);
+    blk_wait_while_drained(blk, flags);
     GRAPH_RDLOCK_GUARD();
 
     ret = blk_check_byte_request(blk, offset, bytes);
@@ -1824,7 +1825,7 @@ static void coroutine_fn blk_aio_pdiscard_entry(void *opaque)
     BlkAioEmAIOCB *acb = opaque;
     BlkRwCo *rwco = &acb->rwco;
 
-    rwco->ret = blk_co_do_pdiscard(rwco->blk, rwco->offset, acb->bytes);
+    rwco->ret = blk_co_do_pdiscard(rwco->blk, rwco->offset, acb->bytes, 0);
     blk_aio_complete(acb);
 }
 
@@ -1838,13 +1839,13 @@ BlockAIOCB *blk_aio_pdiscard(BlockBackend *blk,
 }
 
 int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset,
-                                 int64_t bytes)
+                                 int64_t bytes, BdrvRequestFlags flags)
 {
     int ret;
     IO_OR_GS_CODE();
 
     blk_inc_in_flight(blk);
-    ret = blk_co_do_pdiscard(blk, offset, bytes);
+    ret = blk_co_do_pdiscard(blk, offset, bytes, flags);
     blk_dec_in_flight(blk);
 
     return ret;
diff --git a/block/export/virtio-blk-handler.c b/block/export/virtio-blk-handler.c
index bc1cec6757..b82baae553 100644
--- a/block/export/virtio-blk-handler.c
+++ b/block/export/virtio-blk-handler.c
@@ -121,7 +121,7 @@ virtio_blk_discard_write_zeroes(VirtioBlkHandler *handler, struct iovec *iov,
         }
 
         if (blk_co_pdiscard(blk, sector << VIRTIO_BLK_SECTOR_BITS,
-                            bytes) == 0) {
+                            bytes, 0) == 0) {
             return VIRTIO_BLK_S_OK;
         }
     }
diff --git a/block/mirror.c b/block/mirror.c
index f01be99b55..c87f1e205b 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -454,7 +454,7 @@ static void coroutine_fn mirror_co_discard(void *opaque)
     *op->bytes_handled = op->bytes;
     op->is_in_flight = true;
 
-    ret = blk_co_pdiscard(op->s->target, op->offset, op->bytes);
+    ret = blk_co_pdiscard(op->s->target, op->offset, op->bytes, 0);
     mirror_write_complete(op, ret);
 }
 
@@ -1527,7 +1527,7 @@ do_sync_target_write(MirrorBlockJob *job, MirrorMethod method,
                          zero_bitmap_end - zero_bitmap_offset);
         }
         assert(!qiov);
-        ret = blk_co_pdiscard(job->target, offset, bytes);
+        ret = blk_co_pdiscard(job->target, offset, bytes, 0);
         break;
 
     default:
diff --git a/include/system/block-backend-io.h b/include/system/block-backend-io.h
index 59841e04a8..91c48299b7 100644
--- a/include/system/block-backend-io.h
+++ b/include/system/block-backend-io.h
@@ -217,9 +217,9 @@ int co_wrapper_mixed blk_zone_append(BlockBackend *blk, int64_t *offset,
                                          BdrvRequestFlags flags);
 
 int co_wrapper_mixed blk_pdiscard(BlockBackend *blk, int64_t offset,
-                                  int64_t bytes);
+                                  int64_t bytes, BdrvRequestFlags flags);
 int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset,
-                                 int64_t bytes);
+                                 int64_t bytes, BdrvRequestFlags flags);
 
 int co_wrapper_mixed blk_flush(BlockBackend *blk);
 int coroutine_fn blk_co_flush(BlockBackend *blk);
diff --git a/nbd/server.c b/nbd/server.c
index acec0487a8..bd103a8840 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -2984,7 +2984,7 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
                                       "flush failed", errp);
 
     case NBD_CMD_TRIM:
-        ret = blk_co_pdiscard(exp->common.blk, request->from, request->len);
+        ret = blk_co_pdiscard(exp->common.blk, request->from, request->len, 0);
         if (ret >= 0 && request->flags & NBD_CMD_FLAG_FUA) {
             ret = blk_co_flush(exp->common.blk);
         }
diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index 13e0330162..f6d077908f 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -2201,7 +2201,7 @@ static int discard_f(BlockBackend *blk, int argc, char **argv)
     }
 
     clock_gettime(CLOCK_MONOTONIC, &t1);
-    ret = blk_pdiscard(blk, offset, bytes);
+    ret = blk_pdiscard(blk, offset, bytes, 0);
     clock_gettime(CLOCK_MONOTONIC, &t2);
 
     if (ret < 0) {
diff --git a/tests/unit/test-block-iothread.c b/tests/unit/test-block-iothread.c
index e26b3be593..5273ff235a 100644
--- a/tests/unit/test-block-iothread.c
+++ b/tests/unit/test-block-iothread.c
@@ -270,11 +270,11 @@ static void test_sync_op_blk_pdiscard(BlockBackend *blk)
     int ret;
 
     /* Early success: UNMAP not supported */
-    ret = blk_pdiscard(blk, 0, 512);
+    ret = blk_pdiscard(blk, 0, 512, 0);
     g_assert_cmpint(ret, ==, 0);
 
     /* Early error: Negative offset */
-    ret = blk_pdiscard(blk, -2, 512);
+    ret = blk_pdiscard(blk, -2, 512, 0);
     g_assert_cmpint(ret, ==, -EIO);
 }
 
-- 
2.52.0