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virtio-blk.c
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virtio-blk.c
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/*
* Virtio Block Device
*
* Copyright IBM, Corp. 2007
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/iov.h"
#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"
#include "sysemu/blockdev.h"
#include "sysemu/block-ram-registrar.h"
#include "sysemu/sysemu.h"
#include "sysemu/runstate.h"
#include "hw/virtio/virtio-blk.h"
#include "dataplane/virtio-blk.h"
#include "scsi/constants.h"
#ifdef __linux__
# include <scsi/sg.h>
#endif
#include "hw/virtio/virtio-bus.h"
#include "migration/qemu-file-types.h"
#include "hw/virtio/virtio-access.h"
#include "hw/virtio/virtio-blk-common.h"
#include "qemu/coroutine.h"
static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq,
VirtIOBlockReq *req)
{
req->dev = s;
req->vq = vq;
req->qiov.size = 0;
req->in_len = 0;
req->next = NULL;
req->mr_next = NULL;
}
static void virtio_blk_free_request(VirtIOBlockReq *req)
{
g_free(req);
}
static void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char status)
{
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
trace_virtio_blk_req_complete(vdev, req, status);
stb_p(&req->in->status, status);
iov_discard_undo(&req->inhdr_undo);
iov_discard_undo(&req->outhdr_undo);
virtqueue_push(req->vq, &req->elem, req->in_len);
if (s->dataplane_started && !s->dataplane_disabled) {
virtio_blk_data_plane_notify(s->dataplane, req->vq);
} else {
virtio_notify(vdev, req->vq);
}
}
static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error,
bool is_read, bool acct_failed)
{
VirtIOBlock *s = req->dev;
BlockErrorAction action = blk_get_error_action(s->blk, is_read, error);
if (action == BLOCK_ERROR_ACTION_STOP) {
/* Break the link as the next request is going to be parsed from the
* ring again. Otherwise we may end up doing a double completion! */
req->mr_next = NULL;
req->next = s->rq;
s->rq = req;
} else if (action == BLOCK_ERROR_ACTION_REPORT) {
virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
if (acct_failed) {
block_acct_failed(blk_get_stats(s->blk), &req->acct);
}
virtio_blk_free_request(req);
}
blk_error_action(s->blk, action, is_read, error);
return action != BLOCK_ERROR_ACTION_IGNORE;
}
static void virtio_blk_rw_complete(void *opaque, int ret)
{
VirtIOBlockReq *next = opaque;
VirtIOBlock *s = next->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
while (next) {
VirtIOBlockReq *req = next;
next = req->mr_next;
trace_virtio_blk_rw_complete(vdev, req, ret);
if (req->qiov.nalloc != -1) {
/* If nalloc is != -1 req->qiov is a local copy of the original
* external iovec. It was allocated in submit_requests to be
* able to merge requests. */
qemu_iovec_destroy(&req->qiov);
}
if (ret) {
int p = virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type);
bool is_read = !(p & VIRTIO_BLK_T_OUT);
/* Note that memory may be dirtied on read failure. If the
* virtio request is not completed here, as is the case for
* BLOCK_ERROR_ACTION_STOP, the memory may not be copied
* correctly during live migration. While this is ugly,
* it is acceptable because the device is free to write to
* the memory until the request is completed (which will
* happen on the other side of the migration).
*/
if (virtio_blk_handle_rw_error(req, -ret, is_read, true)) {
continue;
}
}
virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
block_acct_done(blk_get_stats(s->blk), &req->acct);
virtio_blk_free_request(req);
}
aio_context_release(blk_get_aio_context(s->conf.conf.blk));
}
static void virtio_blk_flush_complete(void *opaque, int ret)
{
VirtIOBlockReq *req = opaque;
VirtIOBlock *s = req->dev;
aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
if (ret) {
if (virtio_blk_handle_rw_error(req, -ret, 0, true)) {
goto out;
}
}
virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
block_acct_done(blk_get_stats(s->blk), &req->acct);
virtio_blk_free_request(req);
out:
aio_context_release(blk_get_aio_context(s->conf.conf.blk));
}
static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret)
{
VirtIOBlockReq *req = opaque;
VirtIOBlock *s = req->dev;
bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) &
~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES;
aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
if (ret) {
if (virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) {
goto out;
}
}
virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
if (is_write_zeroes) {
block_acct_done(blk_get_stats(s->blk), &req->acct);
}
virtio_blk_free_request(req);
out:
aio_context_release(blk_get_aio_context(s->conf.conf.blk));
}
#ifdef __linux__
typedef struct {
VirtIOBlockReq *req;
struct sg_io_hdr hdr;
} VirtIOBlockIoctlReq;
static void virtio_blk_ioctl_complete(void *opaque, int status)
{
VirtIOBlockIoctlReq *ioctl_req = opaque;
VirtIOBlockReq *req = ioctl_req->req;
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
struct virtio_scsi_inhdr *scsi;
struct sg_io_hdr *hdr;
scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base;
if (status) {
status = VIRTIO_BLK_S_UNSUPP;
virtio_stl_p(vdev, &scsi->errors, 255);
goto out;
}
hdr = &ioctl_req->hdr;
/*
* From SCSI-Generic-HOWTO: "Some lower level drivers (e.g. ide-scsi)
* clear the masked_status field [hence status gets cleared too, see
* block/scsi_ioctl.c] even when a CHECK_CONDITION or COMMAND_TERMINATED
* status has occurred. However they do set DRIVER_SENSE in driver_status
* field. Also a (sb_len_wr > 0) indicates there is a sense buffer.
*/
if (hdr->status == 0 && hdr->sb_len_wr > 0) {
hdr->status = CHECK_CONDITION;
}
virtio_stl_p(vdev, &scsi->errors,
hdr->status | (hdr->msg_status << 8) |
(hdr->host_status << 16) | (hdr->driver_status << 24));
virtio_stl_p(vdev, &scsi->residual, hdr->resid);
virtio_stl_p(vdev, &scsi->sense_len, hdr->sb_len_wr);
virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len);
out:
aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
virtio_blk_req_complete(req, status);
virtio_blk_free_request(req);
aio_context_release(blk_get_aio_context(s->conf.conf.blk));
g_free(ioctl_req);
}
#endif
static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s, VirtQueue *vq)
{
VirtIOBlockReq *req = virtqueue_pop(vq, sizeof(VirtIOBlockReq));
if (req) {
virtio_blk_init_request(s, vq, req);
}
return req;
}
static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req)
{
int status = VIRTIO_BLK_S_OK;
struct virtio_scsi_inhdr *scsi = NULL;
VirtIOBlock *blk = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(blk);
VirtQueueElement *elem = &req->elem;
#ifdef __linux__
int i;
VirtIOBlockIoctlReq *ioctl_req;
BlockAIOCB *acb;
#endif
/*
* We require at least one output segment each for the virtio_blk_outhdr
* and the SCSI command block.
*
* We also at least require the virtio_blk_inhdr, the virtio_scsi_inhdr
* and the sense buffer pointer in the input segments.
*/
if (elem->out_num < 2 || elem->in_num < 3) {
status = VIRTIO_BLK_S_IOERR;
goto fail;
}
/*
* The scsi inhdr is placed in the second-to-last input segment, just
* before the regular inhdr.
*/
scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base;
if (!virtio_has_feature(blk->host_features, VIRTIO_BLK_F_SCSI)) {
status = VIRTIO_BLK_S_UNSUPP;
goto fail;
}
/*
* No support for bidirection commands yet.
*/
if (elem->out_num > 2 && elem->in_num > 3) {
status = VIRTIO_BLK_S_UNSUPP;
goto fail;
}
#ifdef __linux__
ioctl_req = g_new0(VirtIOBlockIoctlReq, 1);
ioctl_req->req = req;
ioctl_req->hdr.interface_id = 'S';
ioctl_req->hdr.cmd_len = elem->out_sg[1].iov_len;
ioctl_req->hdr.cmdp = elem->out_sg[1].iov_base;
ioctl_req->hdr.dxfer_len = 0;
if (elem->out_num > 2) {
/*
* If there are more than the minimally required 2 output segments
* there is write payload starting from the third iovec.
*/
ioctl_req->hdr.dxfer_direction = SG_DXFER_TO_DEV;
ioctl_req->hdr.iovec_count = elem->out_num - 2;
for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
ioctl_req->hdr.dxfer_len += elem->out_sg[i + 2].iov_len;
}
ioctl_req->hdr.dxferp = elem->out_sg + 2;
} else if (elem->in_num > 3) {
/*
* If we have more than 3 input segments the guest wants to actually
* read data.
*/
ioctl_req->hdr.dxfer_direction = SG_DXFER_FROM_DEV;
ioctl_req->hdr.iovec_count = elem->in_num - 3;
for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
ioctl_req->hdr.dxfer_len += elem->in_sg[i].iov_len;
}
ioctl_req->hdr.dxferp = elem->in_sg;
} else {
/*
* Some SCSI commands don't actually transfer any data.
*/
ioctl_req->hdr.dxfer_direction = SG_DXFER_NONE;
}
ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base;
ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len;
acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr,
virtio_blk_ioctl_complete, ioctl_req);
if (!acb) {
g_free(ioctl_req);
status = VIRTIO_BLK_S_UNSUPP;
goto fail;
}
return -EINPROGRESS;
#else
abort();
#endif
fail:
/* Just put anything nonzero so that the ioctl fails in the guest. */
if (scsi) {
virtio_stl_p(vdev, &scsi->errors, 255);
}
return status;
}
static void virtio_blk_handle_scsi(VirtIOBlockReq *req)
{
int status;
status = virtio_blk_handle_scsi_req(req);
if (status != -EINPROGRESS) {
virtio_blk_req_complete(req, status);
virtio_blk_free_request(req);
}
}
static inline void submit_requests(VirtIOBlock *s, MultiReqBuffer *mrb,
int start, int num_reqs, int niov)
{
BlockBackend *blk = s->blk;
QEMUIOVector *qiov = &mrb->reqs[start]->qiov;
int64_t sector_num = mrb->reqs[start]->sector_num;
bool is_write = mrb->is_write;
BdrvRequestFlags flags = 0;
if (num_reqs > 1) {
int i;
struct iovec *tmp_iov = qiov->iov;
int tmp_niov = qiov->niov;
/* mrb->reqs[start]->qiov was initialized from external so we can't
* modify it here. We need to initialize it locally and then add the
* external iovecs. */
qemu_iovec_init(qiov, niov);
for (i = 0; i < tmp_niov; i++) {
qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len);
}
for (i = start + 1; i < start + num_reqs; i++) {
qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0,
mrb->reqs[i]->qiov.size);
mrb->reqs[i - 1]->mr_next = mrb->reqs[i];
}
trace_virtio_blk_submit_multireq(VIRTIO_DEVICE(mrb->reqs[start]->dev),
mrb, start, num_reqs,
sector_num << BDRV_SECTOR_BITS,
qiov->size, is_write);
block_acct_merge_done(blk_get_stats(blk),
is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ,
num_reqs - 1);
}
if (blk_ram_registrar_ok(&s->blk_ram_registrar)) {
flags |= BDRV_REQ_REGISTERED_BUF;
}
if (is_write) {
blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov,
flags, virtio_blk_rw_complete,
mrb->reqs[start]);
} else {
blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov,
flags, virtio_blk_rw_complete,
mrb->reqs[start]);
}
}
static int multireq_compare(const void *a, const void *b)
{
const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a,
*req2 = *(VirtIOBlockReq **)b;
/*
* Note that we can't simply subtract sector_num1 from sector_num2
* here as that could overflow the return value.
*/
if (req1->sector_num > req2->sector_num) {
return 1;
} else if (req1->sector_num < req2->sector_num) {
return -1;
} else {
return 0;
}
}
static void virtio_blk_submit_multireq(VirtIOBlock *s, MultiReqBuffer *mrb)
{
int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0;
uint32_t max_transfer;
int64_t sector_num = 0;
if (mrb->num_reqs == 1) {
submit_requests(s, mrb, 0, 1, -1);
mrb->num_reqs = 0;
return;
}
max_transfer = blk_get_max_transfer(mrb->reqs[0]->dev->blk);
qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs),
&multireq_compare);
for (i = 0; i < mrb->num_reqs; i++) {
VirtIOBlockReq *req = mrb->reqs[i];
if (num_reqs > 0) {
/*
* NOTE: We cannot merge the requests in below situations:
* 1. requests are not sequential
* 2. merge would exceed maximum number of IOVs
* 3. merge would exceed maximum transfer length of backend device
*/
if (sector_num + nb_sectors != req->sector_num ||
niov > blk_get_max_iov(s->blk) - req->qiov.niov ||
req->qiov.size > max_transfer ||
nb_sectors > (max_transfer -
req->qiov.size) / BDRV_SECTOR_SIZE) {
submit_requests(s, mrb, start, num_reqs, niov);
num_reqs = 0;
}
}
if (num_reqs == 0) {
sector_num = req->sector_num;
nb_sectors = niov = 0;
start = i;
}
nb_sectors += req->qiov.size / BDRV_SECTOR_SIZE;
niov += req->qiov.niov;
num_reqs++;
}
submit_requests(s, mrb, start, num_reqs, niov);
mrb->num_reqs = 0;
}
static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb)
{
VirtIOBlock *s = req->dev;
block_acct_start(blk_get_stats(s->blk), &req->acct, 0,
BLOCK_ACCT_FLUSH);
/*
* Make sure all outstanding writes are posted to the backing device.
*/
if (mrb->is_write && mrb->num_reqs > 0) {
virtio_blk_submit_multireq(s, mrb);
}
blk_aio_flush(s->blk, virtio_blk_flush_complete, req);
}
static bool virtio_blk_sect_range_ok(VirtIOBlock *dev,
uint64_t sector, size_t size)
{
uint64_t nb_sectors = size >> BDRV_SECTOR_BITS;
uint64_t total_sectors;
if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) {
return false;
}
if (sector & dev->sector_mask) {
return false;
}
if (size % dev->conf.conf.logical_block_size) {
return false;
}
blk_get_geometry(dev->blk, &total_sectors);
if (sector > total_sectors || nb_sectors > total_sectors - sector) {
return false;
}
return true;
}
static uint8_t virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq *req,
struct virtio_blk_discard_write_zeroes *dwz_hdr, bool is_write_zeroes)
{
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
uint64_t sector;
uint32_t num_sectors, flags, max_sectors;
uint8_t err_status;
int bytes;
sector = virtio_ldq_p(vdev, &dwz_hdr->sector);
num_sectors = virtio_ldl_p(vdev, &dwz_hdr->num_sectors);
flags = virtio_ldl_p(vdev, &dwz_hdr->flags);
max_sectors = is_write_zeroes ? s->conf.max_write_zeroes_sectors :
s->conf.max_discard_sectors;
/*
* max_sectors is at most BDRV_REQUEST_MAX_SECTORS, this check
* make us sure that "num_sectors << BDRV_SECTOR_BITS" can fit in
* the integer variable.
*/
if (unlikely(num_sectors > max_sectors)) {
err_status = VIRTIO_BLK_S_IOERR;
goto err;
}
bytes = num_sectors << BDRV_SECTOR_BITS;
if (unlikely(!virtio_blk_sect_range_ok(s, sector, bytes))) {
err_status = VIRTIO_BLK_S_IOERR;
goto err;
}
/*
* The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for discard
* and write zeroes commands if any unknown flag is set.
*/
if (unlikely(flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
err_status = VIRTIO_BLK_S_UNSUPP;
goto err;
}
if (is_write_zeroes) { /* VIRTIO_BLK_T_WRITE_ZEROES */
int blk_aio_flags = 0;
if (flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) {
blk_aio_flags |= BDRV_REQ_MAY_UNMAP;
}
block_acct_start(blk_get_stats(s->blk), &req->acct, bytes,
BLOCK_ACCT_WRITE);
blk_aio_pwrite_zeroes(s->blk, sector << BDRV_SECTOR_BITS,
bytes, blk_aio_flags,
virtio_blk_discard_write_zeroes_complete, req);
} else { /* VIRTIO_BLK_T_DISCARD */
/*
* The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for
* discard commands if the unmap flag is set.
*/
if (unlikely(flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
err_status = VIRTIO_BLK_S_UNSUPP;
goto err;
}
blk_aio_pdiscard(s->blk, sector << BDRV_SECTOR_BITS, bytes,
virtio_blk_discard_write_zeroes_complete, req);
}
return VIRTIO_BLK_S_OK;
err:
if (is_write_zeroes) {
block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_WRITE);
}
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;
struct iovec *in_iov = req->elem.in_sg;
struct iovec *out_iov = req->elem.out_sg;
unsigned in_num = req->elem.in_num;
unsigned out_num = req->elem.out_num;
VirtIOBlock *s = req->dev;
VirtIODevice *vdev = VIRTIO_DEVICE(s);
if (req->elem.out_num < 1 || req->elem.in_num < 1) {
virtio_error(vdev, "virtio-blk missing headers");
return -1;
}
if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
sizeof(req->out)) != sizeof(req->out))) {
virtio_error(vdev, "virtio-blk request outhdr too short");
return -1;
}
iov_discard_front_undoable(&out_iov, &out_num, sizeof(req->out),
&req->outhdr_undo);
if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
virtio_error(vdev, "virtio-blk request inhdr too short");
iov_discard_undo(&req->outhdr_undo);
return -1;
}
/* We always touch the last byte, so just see how big in_iov is. */
req->in_len = iov_size(in_iov, in_num);
req->in = (void *)in_iov[in_num - 1].iov_base
+ in_iov[in_num - 1].iov_len
- sizeof(struct virtio_blk_inhdr);
iov_discard_back_undoable(in_iov, &in_num, sizeof(struct virtio_blk_inhdr),
&req->inhdr_undo);
type = virtio_ldl_p(vdev, &req->out.type);
/* VIRTIO_BLK_T_OUT defines the command direction. VIRTIO_BLK_T_BARRIER
* is an optional flag. Although a guest should not send this flag if
* not negotiated we ignored it in the past. So keep ignoring it. */
switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) {
case VIRTIO_BLK_T_IN:
{
bool is_write = type & VIRTIO_BLK_T_OUT;
req->sector_num = virtio_ldq_p(vdev, &req->out.sector);
if (is_write) {
qemu_iovec_init_external(&req->qiov, out_iov, out_num);