[PATCH v4 00/14] block/nvme: Various cleanups required to use multiple queues

[PATCH v4 00/14] block/nvme: Various cleanups required to use multiple queues

[Philippe Mathieu-Daudé]

Hi,

This series is mostly code rearrangement (cleanups) to be
able to split the hardware code from the block driver code,
to be able to use multiple queues on the same hardware, or
multiple block drivers on the same hardware.

All this series is reviewed.

Since v3:
- renamed QUEUE_INDEX_{ADMIN/IO} -> INDEX{ADMIN/IO}
- added stefanha tags

Since v2:
- addressed stefanha review comments
- added 4 trivial patches (to simplify the last one)
- register IRQ notifier for each queuepair (admin and io)

Since v1:
- rebased
- use SCALE_MS definition
- added Stefan's R-b
- addressed Stefan's review comments
  - use union { NvmeIdCtrl / NvmeIdNs }
  - move irq_notifier to NVMeQueuePair
  - removed patches depending on "a tracable hardware stateo
    object instead of BDRVNVMeState".

Phil.

Philippe Mathieu-Daudé (14):
  block/nvme: Replace magic value by SCALE_MS definition
  block/nvme: Avoid further processing if trace event not enabled
  block/nvme: Let nvme_create_queue_pair() fail gracefully
  block/nvme: Define INDEX macros to ease code review
  block/nvme: Improve error message when IO queue creation failed
  block/nvme: Use common error path in nvme_add_io_queue()
  block/nvme: Rename local variable
  block/nvme: Use union of NvmeIdCtrl / NvmeIdNs structures
  block/nvme: Replace qemu_try_blockalign0 by qemu_try_blockalign/memset
  block/nvme: Replace qemu_try_blockalign(bs) by
    qemu_try_memalign(pg_sz)
  block/nvme: Simplify nvme_init_queue() arguments
  block/nvme: Replace BDRV_POLL_WHILE by AIO_WAIT_WHILE
  block/nvme: Simplify nvme_create_queue_pair() arguments
  block/nvme: Extract nvme_poll_queue()

 block/nvme.c | 180 +++++++++++++++++++++++++++++----------------------
 1 file changed, 104 insertions(+), 76 deletions(-)

-- 
2.21.3

[PATCH v4 01/14] block/nvme: Replace magic value by SCALE_MS definition

[Philippe Mathieu-Daudé]

Use self-explicit SCALE_MS definition instead of magic value.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/nvme.c b/block/nvme.c
index 374e268915..2f5e3c2adf 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -715,7 +715,7 @@ static int nvme_init(BlockDriverState *bs, const char *device, int namespace,
     /* Reset device to get a clean state. */
     s->regs->cc = cpu_to_le32(le32_to_cpu(s->regs->cc) & 0xFE);
     /* Wait for CSTS.RDY = 0. */
-    deadline = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ms * 1000000ULL;
+    deadline = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ms * SCALE_MS;
     while (le32_to_cpu(s->regs->csts) & 0x1) {
         if (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) > deadline) {
             error_setg(errp, "Timeout while waiting for device to reset (%"
-- 
2.21.3

[PATCH v4 02/14] block/nvme: Avoid further processing if trace event not enabled

[Philippe Mathieu-Daudé]

Avoid further processing if TRACE_NVME_SUBMIT_COMMAND_RAW is
not enabled. This is an untested intend of performance optimization.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/block/nvme.c b/block/nvme.c
index 2f5e3c2adf..8c30a5fee2 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -441,6 +441,9 @@ static void nvme_trace_command(const NvmeCmd *cmd)
 {
     int i;
 
+    if (!trace_event_get_state_backends(TRACE_NVME_SUBMIT_COMMAND_RAW)) {
+        return;
+    }
     for (i = 0; i < 8; ++i) {
         uint8_t *cmdp = (uint8_t *)cmd + i * 8;
         trace_nvme_submit_command_raw(cmdp[0], cmdp[1], cmdp[2], cmdp[3],
-- 
2.21.3

[PATCH v4 03/14] block/nvme: Let nvme_create_queue_pair() fail gracefully

[Philippe Mathieu-Daudé]

As nvme_create_queue_pair() is allowed to fail, replace the
alloc() calls by try_alloc() to avoid aborting QEMU.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index 8c30a5fee2..e1893b4e79 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -213,14 +213,22 @@ static NVMeQueuePair *nvme_create_queue_pair(BlockDriverState *bs,
     int i, r;
     BDRVNVMeState *s = bs->opaque;
     Error *local_err = NULL;
-    NVMeQueuePair *q = g_new0(NVMeQueuePair, 1);
+    NVMeQueuePair *q;
     uint64_t prp_list_iova;
 
+    q = g_try_new0(NVMeQueuePair, 1);
+    if (!q) {
+        return NULL;
+    }
+    q->prp_list_pages = qemu_try_blockalign0(bs,
+                                          s->page_size * NVME_QUEUE_SIZE);
+    if (!q->prp_list_pages) {
+        goto fail;
+    }
     qemu_mutex_init(&q->lock);
     q->s = s;
     q->index = idx;
     qemu_co_queue_init(&q->free_req_queue);
-    q->prp_list_pages = qemu_blockalign0(bs, s->page_size * NVME_NUM_REQS);
     q->completion_bh = aio_bh_new(bdrv_get_aio_context(bs),
                                   nvme_process_completion_bh, q);
     r = qemu_vfio_dma_map(s->vfio, q->prp_list_pages,
-- 
2.21.3

[PATCH v4 04/14] block/nvme: Define INDEX macros to ease code review

[Philippe Mathieu-Daudé]

Use definitions instead of '0' or '1' indexes. Also this will
be useful when using multi-queues later.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 33 +++++++++++++++++++--------------
 1 file changed, 19 insertions(+), 14 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index e1893b4e79..003809fbd8 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -103,6 +103,9 @@ typedef volatile struct {
 
 QEMU_BUILD_BUG_ON(offsetof(NVMeRegs, doorbells) != 0x1000);
 
+#define INDEX_ADMIN     0
+#define INDEX_IO(n)     (1 + n)
+
 struct BDRVNVMeState {
     AioContext *aio_context;
     QEMUVFIOState *vfio;
@@ -531,7 +534,7 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
     }
     cmd.prp1 = cpu_to_le64(iova);
 
-    if (nvme_cmd_sync(bs, s->queues[0], &cmd)) {
+    if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
         error_setg(errp, "Failed to identify controller");
         goto out;
     }
@@ -555,7 +558,7 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
 
     cmd.cdw10 = 0;
     cmd.nsid = cpu_to_le32(namespace);
-    if (nvme_cmd_sync(bs, s->queues[0], &cmd)) {
+    if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
         error_setg(errp, "Failed to identify namespace");
         goto out;
     }
@@ -644,7 +647,7 @@ static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp)
         .cdw10 = cpu_to_le32(((queue_size - 1) << 16) | (n & 0xFFFF)),
         .cdw11 = cpu_to_le32(0x3),
     };
-    if (nvme_cmd_sync(bs, s->queues[0], &cmd)) {
+    if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
         error_setg(errp, "Failed to create io queue [%d]", n);
         nvme_free_queue_pair(q);
         return false;
@@ -655,7 +658,7 @@ static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp)
         .cdw10 = cpu_to_le32(((queue_size - 1) << 16) | (n & 0xFFFF)),
         .cdw11 = cpu_to_le32(0x1 | (n << 16)),
     };
-    if (nvme_cmd_sync(bs, s->queues[0], &cmd)) {
+    if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
         error_setg(errp, "Failed to create io queue [%d]", n);
         nvme_free_queue_pair(q);
         return false;
@@ -739,16 +742,18 @@ static int nvme_init(BlockDriverState *bs, const char *device, int namespace,
 
     /* Set up admin queue. */
     s->queues = g_new(NVMeQueuePair *, 1);
-    s->queues[0] = nvme_create_queue_pair(bs, 0, NVME_QUEUE_SIZE, errp);
-    if (!s->queues[0]) {
+    s->queues[INDEX_ADMIN] = nvme_create_queue_pair(bs, 0,
+                                                          NVME_QUEUE_SIZE,
+                                                          errp);
+    if (!s->queues[INDEX_ADMIN]) {
         ret = -EINVAL;
         goto out;
     }
     s->nr_queues = 1;
     QEMU_BUILD_BUG_ON(NVME_QUEUE_SIZE & 0xF000);
     s->regs->aqa = cpu_to_le32((NVME_QUEUE_SIZE << 16) | NVME_QUEUE_SIZE);
-    s->regs->asq = cpu_to_le64(s->queues[0]->sq.iova);
-    s->regs->acq = cpu_to_le64(s->queues[0]->cq.iova);
+    s->regs->asq = cpu_to_le64(s->queues[INDEX_ADMIN]->sq.iova);
+    s->regs->acq = cpu_to_le64(s->queues[INDEX_ADMIN]->cq.iova);
 
     /* After setting up all control registers we can enable device now. */
     s->regs->cc = cpu_to_le32((ctz32(NVME_CQ_ENTRY_BYTES) << 20) |
@@ -839,7 +844,7 @@ static int nvme_enable_disable_write_cache(BlockDriverState *bs, bool enable,
         .cdw11 = cpu_to_le32(enable ? 0x01 : 0x00),
     };
 
-    ret = nvme_cmd_sync(bs, s->queues[0], &cmd);
+    ret = nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd);
     if (ret) {
         error_setg(errp, "Failed to configure NVMe write cache");
     }
@@ -1056,7 +1061,7 @@ static coroutine_fn int nvme_co_prw_aligned(BlockDriverState *bs,
 {
     int r;
     BDRVNVMeState *s = bs->opaque;
-    NVMeQueuePair *ioq = s->queues[1];
+    NVMeQueuePair *ioq = s->queues[INDEX_IO(0)];
     NVMeRequest *req;
 
     uint32_t cdw12 = (((bytes >> s->blkshift) - 1) & 0xFFFF) |
@@ -1171,7 +1176,7 @@ static coroutine_fn int nvme_co_pwritev(BlockDriverState *bs,
 static coroutine_fn int nvme_co_flush(BlockDriverState *bs)
 {
     BDRVNVMeState *s = bs->opaque;
-    NVMeQueuePair *ioq = s->queues[1];
+    NVMeQueuePair *ioq = s->queues[INDEX_IO(0)];
     NVMeRequest *req;
     NvmeCmd cmd = {
         .opcode = NVME_CMD_FLUSH,
@@ -1202,7 +1207,7 @@ static coroutine_fn int nvme_co_pwrite_zeroes(BlockDriverState *bs,
                                               BdrvRequestFlags flags)
 {
     BDRVNVMeState *s = bs->opaque;
-    NVMeQueuePair *ioq = s->queues[1];
+    NVMeQueuePair *ioq = s->queues[INDEX_IO(0)];
     NVMeRequest *req;
 
     uint32_t cdw12 = ((bytes >> s->blkshift) - 1) & 0xFFFF;
@@ -1255,7 +1260,7 @@ static int coroutine_fn nvme_co_pdiscard(BlockDriverState *bs,
                                          int bytes)
 {
     BDRVNVMeState *s = bs->opaque;
-    NVMeQueuePair *ioq = s->queues[1];
+    NVMeQueuePair *ioq = s->queues[INDEX_IO(0)];
     NVMeRequest *req;
     NvmeDsmRange *buf;
     QEMUIOVector local_qiov;
@@ -1398,7 +1403,7 @@ static void nvme_aio_unplug(BlockDriverState *bs)
     BDRVNVMeState *s = bs->opaque;
     assert(s->plugged);
     s->plugged = false;
-    for (i = 1; i < s->nr_queues; i++) {
+    for (i = INDEX_IO(0); i < s->nr_queues; i++) {
         NVMeQueuePair *q = s->queues[i];
         qemu_mutex_lock(&q->lock);
         nvme_kick(q);
-- 
2.21.3

[PATCH v4 05/14] block/nvme: Improve error message when IO queue creation failed

[Philippe Mathieu-Daudé]

Do not use the same error message for different failures.
Display a different error whether it is the CQ or the SQ.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index 003809fbd8..53448b7d23 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -648,7 +648,7 @@ static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp)
         .cdw11 = cpu_to_le32(0x3),
     };
     if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
-        error_setg(errp, "Failed to create io queue [%d]", n);
+        error_setg(errp, "Failed to create CQ io queue [%d]", n);
         nvme_free_queue_pair(q);
         return false;
     }
@@ -659,7 +659,7 @@ static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp)
         .cdw11 = cpu_to_le32(0x1 | (n << 16)),
     };
     if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
-        error_setg(errp, "Failed to create io queue [%d]", n);
+        error_setg(errp, "Failed to create SQ io queue [%d]", n);
         nvme_free_queue_pair(q);
         return false;
     }
-- 
2.21.3

[PATCH v4 06/14] block/nvme: Use common error path in nvme_add_io_queue()

[Philippe Mathieu-Daudé]

Rearrange nvme_add_io_queue() by using a common error path.
This will be proven useful in few commits where we add IRQ
notification to the IO queues.

Reviewed-by: Stefan Hajnoczi <stefanha@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 53448b7d23..3101f1ad55 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -649,8 +649,7 @@ static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp)
     };
     if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
         error_setg(errp, "Failed to create CQ io queue [%d]", n);
-        nvme_free_queue_pair(q);
-        return false;
+        goto out_error;
     }
     cmd = (NvmeCmd) {
         .opcode = NVME_ADM_CMD_CREATE_SQ,
@@ -660,13 +659,15 @@ static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp)
     };
     if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
         error_setg(errp, "Failed to create SQ io queue [%d]", n);
-        nvme_free_queue_pair(q);
-        return false;
+        goto out_error;
     }
     s->queues = g_renew(NVMeQueuePair *, s->queues, n + 1);
     s->queues[n] = q;
     s->nr_queues++;
     return true;
+out_error:
+    nvme_free_queue_pair(q);
+    return false;
 }
 
 static bool nvme_poll_cb(void *opaque)
-- 
2.21.3

[PATCH v4 07/14] block/nvme: Rename local variable

[Philippe Mathieu-Daudé]

We are going to modify the code in the next commit. Renaming
the 'resp' variable to 'id' first makes the next commit easier
to review. No logical changes.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index 3101f1ad55..99822d9fd3 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -510,8 +510,8 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
     BDRVNVMeState *s = bs->opaque;
     NvmeIdCtrl *idctrl;
     NvmeIdNs *idns;
+    uint8_t *id;
     NvmeLBAF *lbaf;
-    uint8_t *resp;
     uint16_t oncs;
     int r;
     uint64_t iova;
@@ -520,14 +520,14 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
         .cdw10 = cpu_to_le32(0x1),
     };
 
-    resp = qemu_try_blockalign0(bs, sizeof(NvmeIdCtrl));
-    if (!resp) {
+    id = qemu_try_blockalign0(bs, sizeof(NvmeIdCtrl));
+    if (!id) {
         error_setg(errp, "Cannot allocate buffer for identify response");
         goto out;
     }
-    idctrl = (NvmeIdCtrl *)resp;
-    idns = (NvmeIdNs *)resp;
-    r = qemu_vfio_dma_map(s->vfio, resp, sizeof(NvmeIdCtrl), true, &iova);
+    idctrl = (NvmeIdCtrl *)id;
+    idns = (NvmeIdNs *)id;
+    r = qemu_vfio_dma_map(s->vfio, id, sizeof(NvmeIdCtrl), true, &iova);
     if (r) {
         error_setg(errp, "Cannot map buffer for DMA");
         goto out;
@@ -554,8 +554,7 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
     s->supports_write_zeroes = !!(oncs & NVME_ONCS_WRITE_ZEROS);
     s->supports_discard = !!(oncs & NVME_ONCS_DSM);
 
-    memset(resp, 0, 4096);
-
+    memset(id, 0, 4096);
     cmd.cdw10 = 0;
     cmd.nsid = cpu_to_le32(namespace);
     if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
@@ -587,8 +586,8 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
 
     s->blkshift = lbaf->ds;
 out:
-    qemu_vfio_dma_unmap(s->vfio, resp);
-    qemu_vfree(resp);
+    qemu_vfio_dma_unmap(s->vfio, id);
+    qemu_vfree(id);
 }
 
 static bool nvme_poll_queues(BDRVNVMeState *s)
-- 
2.21.3

[PATCH v4 08/14] block/nvme: Use union of NvmeIdCtrl / NvmeIdNs structures

[Philippe Mathieu-Daudé]

We allocate an unique chunk of memory then use it for two
different structures. By using an union, we make it clear
the data is overlapping (and we can remove the casts).

Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 31 +++++++++++++++----------------
 1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index 99822d9fd3..2bd1935f95 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -508,9 +508,10 @@ static int nvme_cmd_sync(BlockDriverState *bs, NVMeQueuePair *q,
 static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
 {
     BDRVNVMeState *s = bs->opaque;
-    NvmeIdCtrl *idctrl;
-    NvmeIdNs *idns;
-    uint8_t *id;
+    union {
+        NvmeIdCtrl ctrl;
+        NvmeIdNs ns;
+    } *id;
     NvmeLBAF *lbaf;
     uint16_t oncs;
     int r;
@@ -520,14 +521,12 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
         .cdw10 = cpu_to_le32(0x1),
     };
 
-    id = qemu_try_blockalign0(bs, sizeof(NvmeIdCtrl));
+    id = qemu_try_blockalign0(bs, sizeof(*id));
     if (!id) {
         error_setg(errp, "Cannot allocate buffer for identify response");
         goto out;
     }
-    idctrl = (NvmeIdCtrl *)id;
-    idns = (NvmeIdNs *)id;
-    r = qemu_vfio_dma_map(s->vfio, id, sizeof(NvmeIdCtrl), true, &iova);
+    r = qemu_vfio_dma_map(s->vfio, id, sizeof(*id), true, &iova);
     if (r) {
         error_setg(errp, "Cannot map buffer for DMA");
         goto out;
@@ -539,22 +538,22 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
         goto out;
     }
 
-    if (le32_to_cpu(idctrl->nn) < namespace) {
+    if (le32_to_cpu(id->ctrl.nn) < namespace) {
         error_setg(errp, "Invalid namespace");
         goto out;
     }
-    s->write_cache_supported = le32_to_cpu(idctrl->vwc) & 0x1;
-    s->max_transfer = (idctrl->mdts ? 1 << idctrl->mdts : 0) * s->page_size;
+    s->write_cache_supported = le32_to_cpu(id->ctrl.vwc) & 0x1;
+    s->max_transfer = (id->ctrl.mdts ? 1 << id->ctrl.mdts : 0) * s->page_size;
     /* For now the page list buffer per command is one page, to hold at most
      * s->page_size / sizeof(uint64_t) entries. */
     s->max_transfer = MIN_NON_ZERO(s->max_transfer,
                           s->page_size / sizeof(uint64_t) * s->page_size);
 
-    oncs = le16_to_cpu(idctrl->oncs);
+    oncs = le16_to_cpu(id->ctrl.oncs);
     s->supports_write_zeroes = !!(oncs & NVME_ONCS_WRITE_ZEROS);
     s->supports_discard = !!(oncs & NVME_ONCS_DSM);
 
-    memset(id, 0, 4096);
+    memset(id, 0, sizeof(*id));
     cmd.cdw10 = 0;
     cmd.nsid = cpu_to_le32(namespace);
     if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
@@ -562,11 +561,11 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
         goto out;
     }
 
-    s->nsze = le64_to_cpu(idns->nsze);
-    lbaf = &idns->lbaf[NVME_ID_NS_FLBAS_INDEX(idns->flbas)];
+    s->nsze = le64_to_cpu(id->ns.nsze);
+    lbaf = &id->ns.lbaf[NVME_ID_NS_FLBAS_INDEX(id->ns.flbas)];
 
-    if (NVME_ID_NS_DLFEAT_WRITE_ZEROES(idns->dlfeat) &&
-            NVME_ID_NS_DLFEAT_READ_BEHAVIOR(idns->dlfeat) ==
+    if (NVME_ID_NS_DLFEAT_WRITE_ZEROES(id->ns.dlfeat) &&
+            NVME_ID_NS_DLFEAT_READ_BEHAVIOR(id->ns.dlfeat) ==
                     NVME_ID_NS_DLFEAT_READ_BEHAVIOR_ZEROES) {
         bs->supported_write_flags |= BDRV_REQ_MAY_UNMAP;
     }
-- 
2.21.3

[PATCH v4 09/14] block/nvme: Replace qemu_try_blockalign0 by qemu_try_blockalign/memset

[Philippe Mathieu-Daudé]

In the next commit we'll get rid of qemu_try_blockalign().
To ease review, first replace qemu_try_blockalign0() by explicit
calls to qemu_try_blockalign() and memset().

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index 2bd1935f95..ac6bb52043 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -174,12 +174,12 @@ static void nvme_init_queue(BlockDriverState *bs, NVMeQueue *q,
 
     bytes = ROUND_UP(nentries * entry_bytes, s->page_size);
     q->head = q->tail = 0;
-    q->queue = qemu_try_blockalign0(bs, bytes);
-
+    q->queue = qemu_try_blockalign(bs, bytes);
     if (!q->queue) {
         error_setg(errp, "Cannot allocate queue");
         return;
     }
+    memset(q->queue, 0, bytes);
     r = qemu_vfio_dma_map(s->vfio, q->queue, bytes, false, &q->iova);
     if (r) {
         error_setg(errp, "Cannot map queue");
@@ -223,11 +223,12 @@ static NVMeQueuePair *nvme_create_queue_pair(BlockDriverState *bs,
     if (!q) {
         return NULL;
     }
-    q->prp_list_pages = qemu_try_blockalign0(bs,
+    q->prp_list_pages = qemu_try_blockalign(bs,
                                           s->page_size * NVME_QUEUE_SIZE);
     if (!q->prp_list_pages) {
         goto fail;
     }
+    memset(q->prp_list_pages, 0, s->page_size * NVME_QUEUE_SIZE);
     qemu_mutex_init(&q->lock);
     q->s = s;
     q->index = idx;
@@ -521,7 +522,7 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
         .cdw10 = cpu_to_le32(0x1),
     };
 
-    id = qemu_try_blockalign0(bs, sizeof(*id));
+    id = qemu_try_blockalign(bs, sizeof(*id));
     if (!id) {
         error_setg(errp, "Cannot allocate buffer for identify response");
         goto out;
@@ -531,8 +532,9 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
         error_setg(errp, "Cannot map buffer for DMA");
         goto out;
     }
-    cmd.prp1 = cpu_to_le64(iova);
 
+    memset(id, 0, sizeof(*id));
+    cmd.prp1 = cpu_to_le64(iova);
     if (nvme_cmd_sync(bs, s->queues[INDEX_ADMIN], &cmd)) {
         error_setg(errp, "Failed to identify controller");
         goto out;
@@ -1283,11 +1285,11 @@ static int coroutine_fn nvme_co_pdiscard(BlockDriverState *bs,
 
     assert(s->nr_queues > 1);
 
-    buf = qemu_try_blockalign0(bs, s->page_size);
+    buf = qemu_try_blockalign(bs, s->page_size);
     if (!buf) {
         return -ENOMEM;
     }
-
+    memset(buf, 0, s->page_size);
     buf->nlb = cpu_to_le32(bytes >> s->blkshift);
     buf->slba = cpu_to_le64(offset >> s->blkshift);
     buf->cattr = 0;
-- 
2.21.3

[PATCH v4 10/14] block/nvme: Replace qemu_try_blockalign(bs) by qemu_try_memalign(pg_sz)

[Philippe Mathieu-Daudé]

qemu_try_blockalign() is a generic API that call back to the
block driver to return its page alignment. As we call from
within the very same driver, we already know to page alignment
stored in our state. Remove indirections and use the value from
BDRVNVMeState.
This change is required to later remove the BlockDriverState
argument, to make nvme_init_queue() per hardware, and not per
block driver.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index ac6bb52043..f180078e78 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -174,7 +174,7 @@ static void nvme_init_queue(BlockDriverState *bs, NVMeQueue *q,
 
     bytes = ROUND_UP(nentries * entry_bytes, s->page_size);
     q->head = q->tail = 0;
-    q->queue = qemu_try_blockalign(bs, bytes);
+    q->queue = qemu_try_memalign(s->page_size, bytes);
     if (!q->queue) {
         error_setg(errp, "Cannot allocate queue");
         return;
@@ -223,7 +223,7 @@ static NVMeQueuePair *nvme_create_queue_pair(BlockDriverState *bs,
     if (!q) {
         return NULL;
     }
-    q->prp_list_pages = qemu_try_blockalign(bs,
+    q->prp_list_pages = qemu_try_memalign(s->page_size,
                                           s->page_size * NVME_QUEUE_SIZE);
     if (!q->prp_list_pages) {
         goto fail;
@@ -522,7 +522,7 @@ static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp)
         .cdw10 = cpu_to_le32(0x1),
     };
 
-    id = qemu_try_blockalign(bs, sizeof(*id));
+    id = qemu_try_memalign(s->page_size, sizeof(*id));
     if (!id) {
         error_setg(errp, "Cannot allocate buffer for identify response");
         goto out;
@@ -1141,7 +1141,7 @@ static int nvme_co_prw(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
         return nvme_co_prw_aligned(bs, offset, bytes, qiov, is_write, flags);
     }
     trace_nvme_prw_buffered(s, offset, bytes, qiov->niov, is_write);
-    buf = qemu_try_blockalign(bs, bytes);
+    buf = qemu_try_memalign(s->page_size, bytes);
 
     if (!buf) {
         return -ENOMEM;
@@ -1285,7 +1285,7 @@ static int coroutine_fn nvme_co_pdiscard(BlockDriverState *bs,
 
     assert(s->nr_queues > 1);
 
-    buf = qemu_try_blockalign(bs, s->page_size);
+    buf = qemu_try_memalign(s->page_size, s->page_size);
     if (!buf) {
         return -ENOMEM;
     }
-- 
2.21.3

[PATCH v4 11/14] block/nvme: Simplify nvme_init_queue() arguments

[Philippe Mathieu-Daudé]

nvme_init_queue() doesn't require BlockDriverState anymore.
Replace it by BDRVNVMeState to simplify.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index f180078e78..5b69fc75a6 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -165,10 +165,9 @@ static QemuOptsList runtime_opts = {
     },
 };
 
-static void nvme_init_queue(BlockDriverState *bs, NVMeQueue *q,
+static void nvme_init_queue(BDRVNVMeState *s, NVMeQueue *q,
                             int nentries, int entry_bytes, Error **errp)
 {
-    BDRVNVMeState *s = bs->opaque;
     size_t bytes;
     int r;
 
@@ -251,14 +250,14 @@ static NVMeQueuePair *nvme_create_queue_pair(BlockDriverState *bs,
         req->prp_list_iova = prp_list_iova + i * s->page_size;
     }
 
-    nvme_init_queue(bs, &q->sq, size, NVME_SQ_ENTRY_BYTES, &local_err);
+    nvme_init_queue(s, &q->sq, size, NVME_SQ_ENTRY_BYTES, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         goto fail;
     }
     q->sq.doorbell = &s->regs->doorbells[idx * 2 * s->doorbell_scale];
 
-    nvme_init_queue(bs, &q->cq, size, NVME_CQ_ENTRY_BYTES, &local_err);
+    nvme_init_queue(s, &q->cq, size, NVME_CQ_ENTRY_BYTES, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         goto fail;
-- 
2.21.3

[PATCH v4 12/14] block/nvme: Replace BDRV_POLL_WHILE by AIO_WAIT_WHILE

[Philippe Mathieu-Daudé]

BDRV_POLL_WHILE() is defined as:

  #define BDRV_POLL_WHILE(bs, cond) ({          \
      BlockDriverState *bs_ = (bs);             \
      AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \
                     cond); })

As we will remove the BlockDriverState use in the next commit,
start by using the exploded version of BDRV_POLL_WHILE().

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/nvme.c b/block/nvme.c
index 5b69fc75a6..456fe61f5e 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -493,6 +493,7 @@ static void nvme_cmd_sync_cb(void *opaque, int ret)
 static int nvme_cmd_sync(BlockDriverState *bs, NVMeQueuePair *q,
                          NvmeCmd *cmd)
 {
+    AioContext *aio_context = bdrv_get_aio_context(bs);
     NVMeRequest *req;
     int ret = -EINPROGRESS;
     req = nvme_get_free_req(q);
@@ -501,7 +502,7 @@ static int nvme_cmd_sync(BlockDriverState *bs, NVMeQueuePair *q,
     }
     nvme_submit_command(q, req, cmd, nvme_cmd_sync_cb, &ret);
 
-    BDRV_POLL_WHILE(bs, ret == -EINPROGRESS);
+    AIO_WAIT_WHILE(aio_context, ret == -EINPROGRESS);
     return ret;
 }
 
-- 
2.21.3

[PATCH v4 13/14] block/nvme: Simplify nvme_create_queue_pair() arguments

[Philippe Mathieu-Daudé]

nvme_create_queue_pair() doesn't require BlockDriverState anymore.
Replace it by BDRVNVMeState and AioContext to simplify.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index 456fe61f5e..1f67e888c8 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -208,12 +208,12 @@ static void nvme_free_req_queue_cb(void *opaque)
     qemu_mutex_unlock(&q->lock);
 }
 
-static NVMeQueuePair *nvme_create_queue_pair(BlockDriverState *bs,
+static NVMeQueuePair *nvme_create_queue_pair(BDRVNVMeState *s,
+                                             AioContext *aio_context,
                                              int idx, int size,
                                              Error **errp)
 {
     int i, r;
-    BDRVNVMeState *s = bs->opaque;
     Error *local_err = NULL;
     NVMeQueuePair *q;
     uint64_t prp_list_iova;
@@ -232,8 +232,7 @@ static NVMeQueuePair *nvme_create_queue_pair(BlockDriverState *bs,
     q->s = s;
     q->index = idx;
     qemu_co_queue_init(&q->free_req_queue);
-    q->completion_bh = aio_bh_new(bdrv_get_aio_context(bs),
-                                  nvme_process_completion_bh, q);
+    q->completion_bh = aio_bh_new(aio_context, nvme_process_completion_bh, q);
     r = qemu_vfio_dma_map(s->vfio, q->prp_list_pages,
                           s->page_size * NVME_NUM_REQS,
                           false, &prp_list_iova);
@@ -637,7 +636,8 @@ static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp)
     NvmeCmd cmd;
     int queue_size = NVME_QUEUE_SIZE;
 
-    q = nvme_create_queue_pair(bs, n, queue_size, errp);
+    q = nvme_create_queue_pair(s, bdrv_get_aio_context(bs),
+                               n, queue_size, errp);
     if (!q) {
         return false;
     }
@@ -683,6 +683,7 @@ static int nvme_init(BlockDriverState *bs, const char *device, int namespace,
                      Error **errp)
 {
     BDRVNVMeState *s = bs->opaque;
+    AioContext *aio_context = bdrv_get_aio_context(bs);
     int ret;
     uint64_t cap;
     uint64_t timeout_ms;
@@ -743,7 +744,7 @@ static int nvme_init(BlockDriverState *bs, const char *device, int namespace,
 
     /* Set up admin queue. */
     s->queues = g_new(NVMeQueuePair *, 1);
-    s->queues[INDEX_ADMIN] = nvme_create_queue_pair(bs, 0,
+    s->queues[INDEX_ADMIN] = nvme_create_queue_pair(s, aio_context, 0,
                                                           NVME_QUEUE_SIZE,
                                                           errp);
     if (!s->queues[INDEX_ADMIN]) {
-- 
2.21.3

[PATCH v4 14/14] block/nvme: Extract nvme_poll_queue()

[Philippe Mathieu-Daudé]

As we want to do per-queue polling, extract the nvme_poll_queue()
method which operates on a single queue.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 block/nvme.c | 44 +++++++++++++++++++++++++++-----------------
 1 file changed, 27 insertions(+), 17 deletions(-)

diff --git a/block/nvme.c b/block/nvme.c
index 1f67e888c8..a61e86a83e 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -590,31 +590,41 @@ out:
     qemu_vfree(id);
 }
 
+static bool nvme_poll_queue(NVMeQueuePair *q)
+{
+    bool progress = false;
+
+    const size_t cqe_offset = q->cq.head * NVME_CQ_ENTRY_BYTES;
+    NvmeCqe *cqe = (NvmeCqe *)&q->cq.queue[cqe_offset];
+
+    /*
+     * Do an early check for completions. q->lock isn't needed because
+     * nvme_process_completion() only runs in the event loop thread and
+     * cannot race with itself.
+     */
+    if ((le16_to_cpu(cqe->status) & 0x1) == q->cq_phase) {
+        return false;
+    }
+
+    qemu_mutex_lock(&q->lock);
+    while (nvme_process_completion(q)) {
+        /* Keep polling */
+        progress = true;
+    }
+    qemu_mutex_unlock(&q->lock);
+
+    return progress;
+}
+
 static bool nvme_poll_queues(BDRVNVMeState *s)
 {
     bool progress = false;
     int i;
 
     for (i = 0; i < s->nr_queues; i++) {
-        NVMeQueuePair *q = s->queues[i];
-        const size_t cqe_offset = q->cq.head * NVME_CQ_ENTRY_BYTES;
-        NvmeCqe *cqe = (NvmeCqe *)&q->cq.queue[cqe_offset];
-
-        /*
-         * Do an early check for completions. q->lock isn't needed because
-         * nvme_process_completion() only runs in the event loop thread and
-         * cannot race with itself.
-         */
-        if ((le16_to_cpu(cqe->status) & 0x1) == q->cq_phase) {
-            continue;
-        }
-
-        qemu_mutex_lock(&q->lock);
-        while (nvme_process_completion(q)) {
-            /* Keep polling */
+        if (nvme_poll_queue(s->queues[i])) {
             progress = true;
         }
-        qemu_mutex_unlock(&q->lock);
     }
     return progress;
 }
-- 
2.21.3