Pull request

This pull request contain's Sam Li's zoned storage support in the QEMU block
 layer and virtio-blk emulation.
 
 v2:
 - Sam fixed the CI failures. CI passes for me now. [Richard]
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Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging

Pull request

This pull request contain's Sam Li's zoned storage support in the QEMU block
layer and virtio-blk emulation.

v2:
- Sam fixed the CI failures. CI passes for me now. [Richard]

# -----BEGIN PGP SIGNATURE-----
#
# iQEzBAABCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmRiWCgACgkQnKSrs4Gr
# c8h/7gf+MMm2cGEaf376t8HMwTc6wbXVfbmAlZrge2EXPZfFvEaxj7HClcEraOgV
# yJsGWeU6mOw4r68ICJ/4KhrY1cdv+VZym/LsMLMcFUTXFHnyX4pyU3am31FPOI4K
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# gpg: Signature made Mon 15 May 2023 09:04:56 AM PDT
# gpg:                using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]

* tag 'block-pull-request' of https://gitlab.com/stefanha/qemu:
  docs/zoned-storage:add zoned emulation use case
  virtio-blk: add some trace events for zoned emulation
  block: add accounting for zone append operation
  virtio-blk: add zoned storage emulation for zoned devices
  block: add some trace events for zone append
  qemu-iotests: test zone append operation
  block: introduce zone append write for zoned devices
  file-posix: add tracking of the zone write pointers
  docs/zoned-storage: add zoned device documentation
  block: add some trace events for new block layer APIs
  iotests: test new zone operations
  block: add zoned BlockDriver check to block layer
  block/raw-format: add zone operations to pass through requests
  block/block-backend: add block layer APIs resembling Linux ZonedBlockDevice ioctls
  block/file-posix: introduce helper functions for sysfs attributes
  block/block-common: add zoned device structs

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2023-05-15 13:54:33 -07:00
commit ab4c44d657
30 changed files with 2106 additions and 58 deletions

View file

@ -44,9 +44,16 @@ pflash_write_unknown(const char *name, uint8_t cmd) "%s: unknown command 0x%02x"
# virtio-blk.c
virtio_blk_req_complete(void *vdev, void *req, int status) "vdev %p req %p status %d"
virtio_blk_rw_complete(void *vdev, void *req, int ret) "vdev %p req %p ret %d"
virtio_blk_zone_report_complete(void *vdev, void *req, unsigned int nr_zones, int ret) "vdev %p req %p nr_zones %u ret %d"
virtio_blk_zone_mgmt_complete(void *vdev, void *req, int ret) "vdev %p req %p ret %d"
virtio_blk_zone_append_complete(void *vdev, void *req, int64_t sector, int ret) "vdev %p req %p, append sector 0x%" PRIx64 " ret %d"
virtio_blk_handle_write(void *vdev, void *req, uint64_t sector, size_t nsectors) "vdev %p req %p sector %"PRIu64" nsectors %zu"
virtio_blk_handle_read(void *vdev, void *req, uint64_t sector, size_t nsectors) "vdev %p req %p sector %"PRIu64" nsectors %zu"
virtio_blk_submit_multireq(void *vdev, void *mrb, int start, int num_reqs, uint64_t offset, size_t size, bool is_write) "vdev %p mrb %p start %d num_reqs %d offset %"PRIu64" size %zu is_write %d"
virtio_blk_handle_zone_report(void *vdev, void *req, int64_t sector, unsigned int nr_zones) "vdev %p req %p sector 0x%" PRIx64 " nr_zones %u"
virtio_blk_handle_zone_mgmt(void *vdev, void *req, uint8_t op, int64_t sector, int64_t len) "vdev %p req %p op 0x%x sector 0x%" PRIx64 " len 0x%" PRIx64 ""
virtio_blk_handle_zone_reset_all(void *vdev, void *req, int64_t sector, int64_t len) "vdev %p req %p sector 0x%" PRIx64 " cap 0x%" PRIx64 ""
virtio_blk_handle_zone_append(void *vdev, void *req, int64_t sector) "vdev %p req %p, append sector 0x%" PRIx64 ""
# hd-geometry.c
hd_geometry_lchs_guess(void *blk, int cyls, int heads, int secs) "blk %p LCHS %d %d %d"

View file

@ -29,6 +29,8 @@ static const VirtIOFeature feature_sizes[] = {
.end = endof(struct virtio_blk_config, discard_sector_alignment)},
{.flags = 1ULL << VIRTIO_BLK_F_WRITE_ZEROES,
.end = endof(struct virtio_blk_config, write_zeroes_may_unmap)},
{.flags = 1ULL << VIRTIO_BLK_F_ZONED,
.end = endof(struct virtio_blk_config, zoned)},
{}
};

View file

@ -17,6 +17,7 @@
#include "qemu/module.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "block/block_int.h"
#include "trace.h"
#include "hw/block/block.h"
#include "hw/qdev-properties.h"
@ -601,6 +602,351 @@ err:
return err_status;
}
typedef struct ZoneCmdData {
VirtIOBlockReq *req;
struct iovec *in_iov;
unsigned in_num;
union {
struct {
unsigned int nr_zones;
BlockZoneDescriptor *zones;
} zone_report_data;
struct {
int64_t offset;
} zone_append_data;
};
} ZoneCmdData;
/*
* check zoned_request: error checking before issuing requests. If all checks
* passed, return true.
* append: true if only zone append requests issued.
*/
static bool check_zoned_request(VirtIOBlock *s, int64_t offset, int64_t len,
bool append, uint8_t *status) {
BlockDriverState *bs = blk_bs(s->blk);
int index;
if (!virtio_has_feature(s->host_features, VIRTIO_BLK_F_ZONED)) {
*status = VIRTIO_BLK_S_UNSUPP;
return false;
}
if (offset < 0 || len < 0 || len > (bs->total_sectors << BDRV_SECTOR_BITS)
|| offset > (bs->total_sectors << BDRV_SECTOR_BITS) - len) {
*status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
return false;
}
if (append) {
if (bs->bl.write_granularity) {
if ((offset % bs->bl.write_granularity) != 0) {
*status = VIRTIO_BLK_S_ZONE_UNALIGNED_WP;
return false;
}
}
index = offset / bs->bl.zone_size;
if (BDRV_ZT_IS_CONV(bs->wps->wp[index])) {
*status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
return false;
}
if (len / 512 > bs->bl.max_append_sectors) {
if (bs->bl.max_append_sectors == 0) {
*status = VIRTIO_BLK_S_UNSUPP;
} else {
*status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
}
return false;
}
}
return true;
}
static void virtio_blk_zone_report_complete(void *opaque, int ret)
{
ZoneCmdData *data = opaque;
VirtIOBlockReq *req = data->req;
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
struct iovec *in_iov = data->in_iov;
unsigned in_num = data->in_num;
int64_t zrp_size, n, j = 0;
int64_t nz = data->zone_report_data.nr_zones;
int8_t err_status = VIRTIO_BLK_S_OK;
trace_virtio_blk_zone_report_complete(vdev, req, nz, ret);
if (ret) {
err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
goto out;
}
struct virtio_blk_zone_report zrp_hdr = (struct virtio_blk_zone_report) {
.nr_zones = cpu_to_le64(nz),
};
zrp_size = sizeof(struct virtio_blk_zone_report)
+ sizeof(struct virtio_blk_zone_descriptor) * nz;
n = iov_from_buf(in_iov, in_num, 0, &zrp_hdr, sizeof(zrp_hdr));
if (n != sizeof(zrp_hdr)) {
virtio_error(vdev, "Driver provided input buffer that is too small!");
err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
goto out;
}
for (size_t i = sizeof(zrp_hdr); i < zrp_size;
i += sizeof(struct virtio_blk_zone_descriptor), ++j) {
struct virtio_blk_zone_descriptor desc =
(struct virtio_blk_zone_descriptor) {
.z_start = cpu_to_le64(data->zone_report_data.zones[j].start
>> BDRV_SECTOR_BITS),
.z_cap = cpu_to_le64(data->zone_report_data.zones[j].cap
>> BDRV_SECTOR_BITS),
.z_wp = cpu_to_le64(data->zone_report_data.zones[j].wp
>> BDRV_SECTOR_BITS),
};
switch (data->zone_report_data.zones[j].type) {
case BLK_ZT_CONV:
desc.z_type = VIRTIO_BLK_ZT_CONV;
break;
case BLK_ZT_SWR:
desc.z_type = VIRTIO_BLK_ZT_SWR;
break;
case BLK_ZT_SWP:
desc.z_type = VIRTIO_BLK_ZT_SWP;
break;
default:
g_assert_not_reached();
}
switch (data->zone_report_data.zones[j].state) {
case BLK_ZS_RDONLY:
desc.z_state = VIRTIO_BLK_ZS_RDONLY;
break;
case BLK_ZS_OFFLINE:
desc.z_state = VIRTIO_BLK_ZS_OFFLINE;
break;
case BLK_ZS_EMPTY:
desc.z_state = VIRTIO_BLK_ZS_EMPTY;
break;
case BLK_ZS_CLOSED:
desc.z_state = VIRTIO_BLK_ZS_CLOSED;
break;
case BLK_ZS_FULL:
desc.z_state = VIRTIO_BLK_ZS_FULL;
break;
case BLK_ZS_EOPEN:
desc.z_state = VIRTIO_BLK_ZS_EOPEN;
break;
case BLK_ZS_IOPEN:
desc.z_state = VIRTIO_BLK_ZS_IOPEN;
break;
case BLK_ZS_NOT_WP:
desc.z_state = VIRTIO_BLK_ZS_NOT_WP;
break;
default:
g_assert_not_reached();
}
/* TODO: it takes O(n^2) time complexity. Optimizations required. */
n = iov_from_buf(in_iov, in_num, i, &desc, sizeof(desc));
if (n != sizeof(desc)) {
virtio_error(vdev, "Driver provided input buffer "
"for descriptors that is too small!");
err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
}
}
out:
aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
virtio_blk_req_complete(req, err_status);
virtio_blk_free_request(req);
aio_context_release(blk_get_aio_context(s->conf.conf.blk));
g_free(data->zone_report_data.zones);
g_free(data);
}
static void virtio_blk_handle_zone_report(VirtIOBlockReq *req,
struct iovec *in_iov,
unsigned in_num)
{
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
unsigned int nr_zones;
ZoneCmdData *data;
int64_t zone_size, offset;
uint8_t err_status;
if (req->in_len < sizeof(struct virtio_blk_inhdr) +
sizeof(struct virtio_blk_zone_report) +
sizeof(struct virtio_blk_zone_descriptor)) {
virtio_error(vdev, "in buffer too small for zone report");
return;
}
/* start byte offset of the zone report */
offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
if (!check_zoned_request(s, offset, 0, false, &err_status)) {
goto out;
}
nr_zones = (req->in_len - sizeof(struct virtio_blk_inhdr) -
sizeof(struct virtio_blk_zone_report)) /
sizeof(struct virtio_blk_zone_descriptor);
trace_virtio_blk_handle_zone_report(vdev, req,
offset >> BDRV_SECTOR_BITS, nr_zones);
zone_size = sizeof(BlockZoneDescriptor) * nr_zones;
data = g_malloc(sizeof(ZoneCmdData));
data->req = req;
data->in_iov = in_iov;
data->in_num = in_num;
data->zone_report_data.nr_zones = nr_zones;
data->zone_report_data.zones = g_malloc(zone_size),
blk_aio_zone_report(s->blk, offset, &data->zone_report_data.nr_zones,
data->zone_report_data.zones,
virtio_blk_zone_report_complete, data);
return;
out:
virtio_blk_req_complete(req, err_status);
virtio_blk_free_request(req);
}
static void virtio_blk_zone_mgmt_complete(void *opaque, int ret)
{
VirtIOBlockReq *req = opaque;
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
int8_t err_status = VIRTIO_BLK_S_OK;
trace_virtio_blk_zone_mgmt_complete(vdev, req,ret);
if (ret) {
err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
}
aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
virtio_blk_req_complete(req, err_status);
virtio_blk_free_request(req);
aio_context_release(blk_get_aio_context(s->conf.conf.blk));
}
static int virtio_blk_handle_zone_mgmt(VirtIOBlockReq *req, BlockZoneOp op)
{
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
BlockDriverState *bs = blk_bs(s->blk);
int64_t offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
uint64_t len;
uint64_t capacity = bs->total_sectors << BDRV_SECTOR_BITS;
uint8_t err_status = VIRTIO_BLK_S_OK;
uint32_t type = virtio_ldl_p(vdev, &req->out.type);
if (type == VIRTIO_BLK_T_ZONE_RESET_ALL) {
/* Entire drive capacity */
offset = 0;
len = capacity;
trace_virtio_blk_handle_zone_reset_all(vdev, req, 0,
bs->total_sectors);
} else {
if (bs->bl.zone_size > capacity - offset) {
/* The zoned device allows the last smaller zone. */
len = capacity - bs->bl.zone_size * (bs->bl.nr_zones - 1);
} else {
len = bs->bl.zone_size;
}
trace_virtio_blk_handle_zone_mgmt(vdev, req, op,
offset >> BDRV_SECTOR_BITS,
len >> BDRV_SECTOR_BITS);
}
if (!check_zoned_request(s, offset, len, false, &err_status)) {
goto out;
}
blk_aio_zone_mgmt(s->blk, op, offset, len,
virtio_blk_zone_mgmt_complete, req);
return 0;
out:
virtio_blk_req_complete(req, err_status);
virtio_blk_free_request(req);
return err_status;
}
static void virtio_blk_zone_append_complete(void *opaque, int ret)
{
ZoneCmdData *data = opaque;
VirtIOBlockReq *req = data->req;
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
int64_t append_sector, n;
uint8_t err_status = VIRTIO_BLK_S_OK;
if (ret) {
err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
goto out;
}
virtio_stq_p(vdev, &append_sector,
data->zone_append_data.offset >> BDRV_SECTOR_BITS);
n = iov_from_buf(data->in_iov, data->in_num, 0, &append_sector,
sizeof(append_sector));
if (n != sizeof(append_sector)) {
virtio_error(vdev, "Driver provided input buffer less than size of "
"append_sector");
err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
goto out;
}
trace_virtio_blk_zone_append_complete(vdev, req, append_sector, ret);
out:
aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
virtio_blk_req_complete(req, err_status);
virtio_blk_free_request(req);
aio_context_release(blk_get_aio_context(s->conf.conf.blk));
g_free(data);
}
static int virtio_blk_handle_zone_append(VirtIOBlockReq *req,
struct iovec *out_iov,
struct iovec *in_iov,
uint64_t out_num,
unsigned in_num) {
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
uint8_t err_status = VIRTIO_BLK_S_OK;
int64_t offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
int64_t len = iov_size(out_iov, out_num);
trace_virtio_blk_handle_zone_append(vdev, req, offset >> BDRV_SECTOR_BITS);
if (!check_zoned_request(s, offset, len, true, &err_status)) {
goto out;
}
ZoneCmdData *data = g_malloc(sizeof(ZoneCmdData));
data->req = req;
data->in_iov = in_iov;
data->in_num = in_num;
data->zone_append_data.offset = offset;
qemu_iovec_init_external(&req->qiov, out_iov, out_num);
block_acct_start(blk_get_stats(s->blk), &req->acct, len,
BLOCK_ACCT_ZONE_APPEND);
blk_aio_zone_append(s->blk, &data->zone_append_data.offset, &req->qiov, 0,
virtio_blk_zone_append_complete, data);
return 0;
out:
aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
virtio_blk_req_complete(req, err_status);
virtio_blk_free_request(req);
aio_context_release(blk_get_aio_context(s->conf.conf.blk));
return err_status;
}
static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
{
uint32_t type;
@ -687,6 +1033,24 @@ static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
case VIRTIO_BLK_T_FLUSH:
virtio_blk_handle_flush(req, mrb);
break;
case VIRTIO_BLK_T_ZONE_REPORT:
virtio_blk_handle_zone_report(req, in_iov, in_num);
break;
case VIRTIO_BLK_T_ZONE_OPEN:
virtio_blk_handle_zone_mgmt(req, BLK_ZO_OPEN);
break;
case VIRTIO_BLK_T_ZONE_CLOSE:
virtio_blk_handle_zone_mgmt(req, BLK_ZO_CLOSE);
break;
case VIRTIO_BLK_T_ZONE_FINISH:
virtio_blk_handle_zone_mgmt(req, BLK_ZO_FINISH);
break;
case VIRTIO_BLK_T_ZONE_RESET:
virtio_blk_handle_zone_mgmt(req, BLK_ZO_RESET);
break;
case VIRTIO_BLK_T_ZONE_RESET_ALL:
virtio_blk_handle_zone_mgmt(req, BLK_ZO_RESET);
break;
case VIRTIO_BLK_T_SCSI_CMD:
virtio_blk_handle_scsi(req);
break;
@ -705,6 +1069,14 @@ static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
virtio_blk_free_request(req);
break;
}
case VIRTIO_BLK_T_ZONE_APPEND & ~VIRTIO_BLK_T_OUT:
/*
* Passing out_iov/out_num and in_iov/in_num is not safe
* to access req->elem.out_sg directly because it may be
* modified by virtio_blk_handle_request().
*/
virtio_blk_handle_zone_append(req, out_iov, in_iov, out_num, in_num);
break;
/*
* VIRTIO_BLK_T_DISCARD and VIRTIO_BLK_T_WRITE_ZEROES are defined with
* VIRTIO_BLK_T_OUT flag set. We masked this flag in the switch statement,
@ -890,6 +1262,7 @@ static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
{
VirtIOBlock *s = VIRTIO_BLK(vdev);
BlockConf *conf = &s->conf.conf;
BlockDriverState *bs = blk_bs(s->blk);
struct virtio_blk_config blkcfg;
uint64_t capacity;
int64_t length;
@ -954,6 +1327,30 @@ static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
blkcfg.write_zeroes_may_unmap = 1;
virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1);
}
if (bs->bl.zoned != BLK_Z_NONE) {
switch (bs->bl.zoned) {
case BLK_Z_HM:
blkcfg.zoned.model = VIRTIO_BLK_Z_HM;
break;
case BLK_Z_HA:
blkcfg.zoned.model = VIRTIO_BLK_Z_HA;
break;
default:
g_assert_not_reached();
}
virtio_stl_p(vdev, &blkcfg.zoned.zone_sectors,
bs->bl.zone_size / 512);
virtio_stl_p(vdev, &blkcfg.zoned.max_active_zones,
bs->bl.max_active_zones);
virtio_stl_p(vdev, &blkcfg.zoned.max_open_zones,
bs->bl.max_open_zones);
virtio_stl_p(vdev, &blkcfg.zoned.write_granularity, blk_size);
virtio_stl_p(vdev, &blkcfg.zoned.max_append_sectors,
bs->bl.max_append_sectors);
} else {
blkcfg.zoned.model = VIRTIO_BLK_Z_NONE;
}
memcpy(config, &blkcfg, s->config_size);
}
@ -1163,6 +1560,14 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
return;
}
BlockDriverState *bs = blk_bs(conf->conf.blk);
if (bs->bl.zoned != BLK_Z_NONE) {
virtio_add_feature(&s->host_features, VIRTIO_BLK_F_ZONED);
if (bs->bl.zoned == BLK_Z_HM) {
virtio_clear_feature(&s->host_features, VIRTIO_BLK_F_DISCARD);
}
}
if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) &&
(!conf->max_discard_sectors ||
conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) {

View file

@ -176,6 +176,8 @@ static const qmp_virtio_feature_map_t virtio_blk_feature_map[] = {
"VIRTIO_BLK_F_DISCARD: Discard command supported"),
FEATURE_ENTRY(VIRTIO_BLK_F_WRITE_ZEROES, \
"VIRTIO_BLK_F_WRITE_ZEROES: Write zeroes command supported"),
FEATURE_ENTRY(VIRTIO_BLK_F_ZONED, \
"VIRTIO_BLK_F_ZONED: Zoned block devices"),
#ifndef VIRTIO_BLK_NO_LEGACY
FEATURE_ENTRY(VIRTIO_BLK_F_BARRIER, \
"VIRTIO_BLK_F_BARRIER: Request barriers supported"),