[PATCH for-7.2 v2 5/6] hw/nvme: fix cancellation handling in dsm

[Klaus Jensen <its@irrelevant.dk>]

From: Klaus Jensen <k.jensen@samsung.com>

When the DSM operation is cancelled asynchronously, we set iocb->ret to
-ECANCELED. However, the callback function only checks the return value
of the completed aio, which may have completed succesfully prior to the
cancellation and thus the callback ends up continuing the dsm operation
instead of bailing out. Fix this.

Fixes: d7d1474fd85d ("hw/nvme: reimplement dsm to allow cancellation")
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
---
 hw/nvme/ctrl.c | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index fa8e4b8dd53a..6f217c3951bd 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -2384,16 +2384,10 @@ static void nvme_dsm_md_cb(void *opaque, int ret)
     uint64_t slba;
     uint32_t nlb;
 
-    if (ret < 0) {
-        iocb->ret = ret;
+    if (ret < 0 || iocb->ret < 0 || !ns->lbaf.ms) {
         goto done;
     }
 
-    if (!ns->lbaf.ms) {
-        nvme_dsm_cb(iocb, 0);
-        return;
-    }
-
     range = &iocb->range[iocb->idx - 1];
     slba = le64_to_cpu(range->slba);
     nlb = le32_to_cpu(range->nlb);
@@ -2406,7 +2400,6 @@ static void nvme_dsm_md_cb(void *opaque, int ret)
     ret = nvme_block_status_all(ns, slba, nlb, BDRV_BLOCK_ZERO);
     if (ret) {
         if (ret < 0) {
-            iocb->ret = ret;
             goto done;
         }
 
@@ -2420,8 +2413,7 @@ static void nvme_dsm_md_cb(void *opaque, int ret)
     return;
 
 done:
-    iocb->aiocb = NULL;
-    qemu_bh_schedule(iocb->bh);
+    nvme_dsm_cb(iocb, ret);
 }
 
 static void nvme_dsm_cb(void *opaque, int ret)
@@ -2434,7 +2426,9 @@ static void nvme_dsm_cb(void *opaque, int ret)
     uint64_t slba;
     uint32_t nlb;
 
-    if (ret < 0) {
+    if (iocb->ret < 0) {
+        goto done;
+    } else if (ret < 0) {
         iocb->ret = ret;
         goto done;
     }
-- 
2.38.1