[PATCH 21/25] block/nvme: Change size and alignment of IDENTIFY response buffer

[Philippe Mathieu-Daudé]

From: Eric Auger <eric.auger@redhat.com>

In preparation of 64kB host page support, let's change the size
and alignment of the IDENTIFY command response buffer so that
the VFIO DMA MAP succeeds. We align on the host page size.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index d2d57a287cc..ad70303c5c1 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -521,19 +521,20 @@ static bool nvme_identify(BlockDriverState *bs, int 
namespace, Error **errp)
         .opcode = NVME_ADM_CMD_IDENTIFY,
         .cdw10 = cpu_to_le32(0x1),
     };
+    size_t id_size = QEMU_ALIGN_UP(sizeof(*id), qemu_real_host_page_size);
 
-    id = qemu_try_memalign(s->page_size, sizeof(*id));
+    id = qemu_try_memalign(qemu_real_host_page_size, id_size);
     if (!id) {
         error_setg(errp, "Cannot allocate buffer for identify response");
         goto out;
     }
-    r = qemu_vfio_dma_map(s->vfio, id, sizeof(*id), true, &iova);
+    r = qemu_vfio_dma_map(s->vfio, id, id_size, true, &iova);
     if (r) {
         error_setg(errp, "Cannot map buffer for DMA");
         goto out;
     }
 
-    memset(id, 0, sizeof(*id));
+    memset(id, 0, id_size);
     cmd.dptr.prp1 = cpu_to_le64(iova);
     if (nvme_cmd_sync(bs, &cmd)) {
         error_setg(errp, "Failed to identify controller");
@@ -555,7 +556,7 @@ static bool nvme_identify(BlockDriverState *bs, int 
namespace, Error **errp)
     s->supports_write_zeroes = !!(oncs & NVME_ONCS_WRITE_ZEROES);
     s->supports_discard = !!(oncs & NVME_ONCS_DSM);
 
-    memset(id, 0, sizeof(*id));
+    memset(id, 0, id_size);
     cmd.cdw10 = 0;
     cmd.nsid = cpu_to_le32(namespace);
     if (nvme_cmd_sync(bs, &cmd)) {
-- 
2.26.2