Hi Klaus,
On 10/22/20 8:49 PM, Klaus Jensen wrote:
From: Klaus Jensen <k.jen...@samsung.com>
Add support for the Dataset Management command and the Deallocate
attribute. Deallocation results in discards being sent to the underlying
block device. Whether of not the blocks are actually deallocated is
affected by the same factors as Write Zeroes (see previous commit).
format | discard | dsm (512b) dsm (4kb) dsm (64kb)
Please use B/KiB units which are unambiguous (kb is for kbits)
(if you queue this yourself, you can fix when applying, no need
to repost).
------------------------------------------------------
qcow2 ignore n n n
qcow2 unmap n n y
raw ignore n n n
raw unmap n y y
Again, a raw format and 4kb LBAs are preferable.
In order to set the Namespace Preferred Deallocate Granularity and
Alignment fields (NPDG and NPDA), choose a sane minimum discard
granularity of 4kb. If we are using a passthru device supporting discard
at a 512b granularity, user should set the discard_granularity property
Ditto.
explicitly. NPDG and NPDA will also account for the cluster_size of the
block driver if required (i.e. for QCOW2).
See NVM Express 1.3d, Section 6.7 ("Dataset Management command").
Signed-off-by: Klaus Jensen <k.jen...@samsung.com>
---
hw/block/nvme.h | 2 +
include/block/nvme.h | 7 ++-
hw/block/nvme-ns.c | 36 +++++++++++++--
hw/block/nvme.c | 101 ++++++++++++++++++++++++++++++++++++++++++-
4 files changed, 140 insertions(+), 6 deletions(-)
diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index e080a2318a50..574333caa3f9 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -28,6 +28,7 @@ typedef struct NvmeRequest {
struct NvmeNamespace *ns;
BlockAIOCB *aiocb;
uint16_t status;
+ void *opaque;
NvmeCqe cqe;
NvmeCmd cmd;
BlockAcctCookie acct;
@@ -60,6 +61,7 @@ static inline const char *nvme_io_opc_str(uint8_t opc)
case NVME_CMD_WRITE: return "NVME_NVM_CMD_WRITE";
case NVME_CMD_READ: return "NVME_NVM_CMD_READ";
case NVME_CMD_WRITE_ZEROES: return "NVME_NVM_CMD_WRITE_ZEROES";
+ case NVME_CMD_DSM: return "NVME_NVM_CMD_DSM";
default: return "NVME_NVM_CMD_UNKNOWN";
}
}
diff --git a/include/block/nvme.h b/include/block/nvme.h
index 966c3bb304bd..e95ff6ca9b37 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -990,7 +990,12 @@ typedef struct QEMU_PACKED NvmeIdNs {
uint16_t nabspf;
uint16_t noiob;
uint8_t nvmcap[16];
- uint8_t rsvd64[40];
+ uint16_t npwg;
+ uint16_t npwa;
+ uint16_t npdg;
+ uint16_t npda;
+ uint16_t nows;
+ uint8_t rsvd74[30];
uint8_t nguid[16];
uint64_t eui64;
NvmeLBAF lbaf[16];
If you consider "block/nvme.h" shared by 2 different subsystems,
it is better to add the changes in a separate patch. That way
the changes can be acked individually.
diff --git a/hw/block/nvme-ns.c b/hw/block/nvme-ns.c
index f1cc734c60f5..840651db7256 100644
--- a/hw/block/nvme-ns.c
+++ b/hw/block/nvme-ns.c
@@ -28,10 +28,14 @@
#include "nvme.h"
#include "nvme-ns.h"
-static void nvme_ns_init(NvmeNamespace *ns)
+#define MIN_DISCARD_GRANULARITY (4 * KiB)
+
+static int nvme_ns_init(NvmeNamespace *ns, Error **errp)
Hmm the Error* argument could be squashed in "hw/block/nvme:
support multiple namespaces". Else better split patch in dumb
units IMHO (maybe a reviewer's taste).
{
+ BlockDriverInfo bdi;
NvmeIdNs *id_ns = &ns->id_ns;
int lba_index = NVME_ID_NS_FLBAS_INDEX(ns->id_ns.flbas);
+ int npdg, ret;
ns->id_ns.dlfeat = 0x9;
@@ -43,8 +47,25 @@ static void nvme_ns_init(NvmeNamespace *ns)
id_ns->ncap = id_ns->nsze;
id_ns->nuse = id_ns->ncap;
- /* support DULBE */
- id_ns->nsfeat |= 0x4;
+ /* support DULBE and I/O optimization fields */
+ id_ns->nsfeat |= (0x4 | 0x10);
The comment helps, but isn't needed if you use explicit definitions
for these flags. You already introduced the NVME_ID_NS_NSFEAT_DULBE
and NVME_ID_NS_FLBAS_EXTENDED but they are restricted to extract bits.
This is why I personally prefer the registerfields API (see
"hw/registerfields.h").
+
+ npdg = ns->blkconf.discard_granularity / ns->blkconf.logical_block_size;
+
+ ret = bdrv_get_info(blk_bs(ns->blkconf.blk), &bdi);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "could not get block driver info");
+ return ret;
+ }
+
+ if (bdi.cluster_size &&
+ bdi.cluster_size > ns->blkconf.discard_granularity) {
+ npdg = bdi.cluster_size / ns->blkconf.logical_block_size;
+ }
+
+ id_ns->npda = id_ns->npdg = npdg - 1;
+
+ return 0;
}
static int nvme_ns_init_blk(NvmeCtrl *n, NvmeNamespace *ns, Error **errp)
@@ -59,6 +80,11 @@ static int nvme_ns_init_blk(NvmeCtrl *n, NvmeNamespace *ns,
Error **errp)
return -1;
}
+ if (ns->blkconf.discard_granularity == -1) {
+ ns->blkconf.discard_granularity =
+ MAX(ns->blkconf.logical_block_size, MIN_DISCARD_GRANULARITY);
+ }
+
ns->size = blk_getlength(ns->blkconf.blk);
if (ns->size < 0) {
error_setg_errno(errp, -ns->size, "could not get blockdev size");
@@ -92,7 +118,9 @@ int nvme_ns_setup(NvmeCtrl *n, NvmeNamespace *ns, Error
**errp)
return -1;
}
- nvme_ns_init(ns);
+ if (nvme_ns_init(ns, errp)) {
+ return -1;
+ }
if (nvme_register_namespace(n, ns, errp)) {
return -1;
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 4ab0705f5a92..7acb9e9dc38a 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -959,6 +959,103 @@ static void nvme_rw_cb(void *opaque, int ret)
nvme_enqueue_req_completion(nvme_cq(req), req);
}
+static void nvme_aio_discard_cb(void *opaque, int ret)
+{
+ NvmeRequest *req = opaque;
+ int *discards = req->opaque;
+
+ trace_pci_nvme_aio_discard_cb(nvme_cid(req));
+
+ if (ret) {
+ req->status = NVME_INTERNAL_DEV_ERROR;
+ trace_pci_nvme_err_aio(nvme_cid(req), strerror(ret),
+ req->status);
+ }
+
+ if (discards && --(*discards) > 0) {
This line is hard to read.
+ return;
+ }
+
+ g_free(req->opaque);
+ req->opaque = NULL;
+
+ nvme_enqueue_req_completion(nvme_cq(req), req);
+}
+
+static uint16_t nvme_dsm(NvmeCtrl *n, NvmeRequest *req)
+{
+ NvmeNamespace *ns = req->ns;
+ NvmeDsmCmd *dsm = (NvmeDsmCmd *) &req->cmd;
+ NvmeDsmRange *range = NULL;
g_autofree?
+ int *discards = NULL;
+
+ uint32_t attr = le32_to_cpu(dsm->attributes);
+ uint32_t nr = (le32_to_cpu(dsm->nr) & 0xff) + 1;
+
+ uint16_t status = NVME_SUCCESS;
+
+ trace_pci_nvme_dsm(nvme_cid(req), nvme_nsid(ns), nr, attr);
+
+ if (attr & NVME_DSMGMT_AD) {
+ int64_t offset;
+ size_t len;
+
+ range = g_new(NvmeDsmRange, nr);
+
+ status = nvme_dma(n, (uint8_t *)range, nr * sizeof(NvmeDsmRange),
+ DMA_DIRECTION_TO_DEVICE, req);
+ if (status) {
+ goto out;
+ }
+
+ discards = g_new(int, 1);
+ *discards = 1;
+ req->opaque = discards;
If opaque is a pointer, why not instead using it as an uintptr_t
discards directly without using the heap?
+
+ for (int i = 0; i < nr; i++) {
+ uint64_t slba = le64_to_cpu(range[i].slba);
+ uint32_t nlb = le32_to_cpu(range[i].nlb);
+
+ if (nvme_check_bounds(n, ns, slba, nlb)) {
+ trace_pci_nvme_err_invalid_lba_range(slba, nlb,
+ ns->id_ns.nsze);
+ continue;
+ }
+
+ trace_pci_nvme_dsm_deallocate(nvme_cid(req), nvme_nsid(ns), slba,
+ nlb);
+
+ offset = nvme_l2b(ns, slba);
+ len = nvme_l2b(ns, nlb);
+
+ while (len) {
+ size_t bytes = MIN(BDRV_REQUEST_MAX_BYTES, len);
+
+ (*discards)++;
+
+ blk_aio_pdiscard(ns->blkconf.blk, offset, bytes,
+ nvme_aio_discard_cb, req);
+
+ offset += bytes;
+ len -= bytes;
+ }
+ }
+
+ if (--(*discards)) {
+ status = NVME_NO_COMPLETE;
+ } else {
+ g_free(discards);
+ req->opaque = NULL;
+ status = req->status;
+ }
+ }
+
+out:
+ g_free(range);
+
+ return status;
+}
[...]
