466138dc68
"werror=report" would free the req in virtio_blk_handle_rw_error, we mustn't write to it in that case. Reported-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com> Message-id: 1448239280-15025-1-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
1025 lines
32 KiB
C
1025 lines
32 KiB
C
/*
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* Virtio Block Device
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*
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* Copyright IBM, Corp. 2007
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*
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* Authors:
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* Anthony Liguori <aliguori@us.ibm.com>
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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*
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*/
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#include "qemu-common.h"
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#include "qemu/iov.h"
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#include "qemu/error-report.h"
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#include "trace.h"
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#include "hw/block/block.h"
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#include "sysemu/block-backend.h"
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#include "sysemu/blockdev.h"
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#include "hw/virtio/virtio-blk.h"
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#include "dataplane/virtio-blk.h"
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#include "migration/migration.h"
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#include "block/scsi.h"
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#ifdef __linux__
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# include <scsi/sg.h>
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#endif
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#include "hw/virtio/virtio-bus.h"
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#include "hw/virtio/virtio-access.h"
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VirtIOBlockReq *virtio_blk_alloc_request(VirtIOBlock *s)
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{
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VirtIOBlockReq *req = g_new(VirtIOBlockReq, 1);
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req->dev = s;
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req->qiov.size = 0;
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req->in_len = 0;
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req->next = NULL;
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req->mr_next = NULL;
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return req;
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}
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void virtio_blk_free_request(VirtIOBlockReq *req)
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{
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if (req) {
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g_free(req);
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}
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}
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static void virtio_blk_complete_request(VirtIOBlockReq *req,
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unsigned char status)
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{
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VirtIOBlock *s = req->dev;
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VirtIODevice *vdev = VIRTIO_DEVICE(s);
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trace_virtio_blk_req_complete(req, status);
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stb_p(&req->in->status, status);
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virtqueue_push(s->vq, &req->elem, req->in_len);
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virtio_notify(vdev, s->vq);
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}
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static void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char status)
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{
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req->dev->complete_request(req, status);
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}
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static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error,
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bool is_read)
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{
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BlockErrorAction action = blk_get_error_action(req->dev->blk,
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is_read, error);
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VirtIOBlock *s = req->dev;
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if (action == BLOCK_ERROR_ACTION_STOP) {
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/* Break the link as the next request is going to be parsed from the
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* ring again. Otherwise we may end up doing a double completion! */
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req->mr_next = NULL;
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req->next = s->rq;
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s->rq = req;
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} else if (action == BLOCK_ERROR_ACTION_REPORT) {
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virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
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block_acct_failed(blk_get_stats(s->blk), &req->acct);
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virtio_blk_free_request(req);
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}
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blk_error_action(s->blk, action, is_read, error);
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return action != BLOCK_ERROR_ACTION_IGNORE;
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}
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static void virtio_blk_rw_complete(void *opaque, int ret)
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{
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VirtIOBlockReq *next = opaque;
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while (next) {
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VirtIOBlockReq *req = next;
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next = req->mr_next;
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trace_virtio_blk_rw_complete(req, ret);
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if (req->qiov.nalloc != -1) {
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/* If nalloc is != 1 req->qiov is a local copy of the original
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* external iovec. It was allocated in submit_merged_requests
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* to be able to merge requests. */
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qemu_iovec_destroy(&req->qiov);
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}
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if (ret) {
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int p = virtio_ldl_p(VIRTIO_DEVICE(req->dev), &req->out.type);
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bool is_read = !(p & VIRTIO_BLK_T_OUT);
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/* Note that memory may be dirtied on read failure. If the
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* virtio request is not completed here, as is the case for
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* BLOCK_ERROR_ACTION_STOP, the memory may not be copied
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* correctly during live migration. While this is ugly,
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* it is acceptable because the device is free to write to
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* the memory until the request is completed (which will
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* happen on the other side of the migration).
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*/
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if (virtio_blk_handle_rw_error(req, -ret, is_read)) {
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continue;
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}
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}
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virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
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block_acct_done(blk_get_stats(req->dev->blk), &req->acct);
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virtio_blk_free_request(req);
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}
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}
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static void virtio_blk_flush_complete(void *opaque, int ret)
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{
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VirtIOBlockReq *req = opaque;
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if (ret) {
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if (virtio_blk_handle_rw_error(req, -ret, 0)) {
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return;
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}
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}
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virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
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block_acct_done(blk_get_stats(req->dev->blk), &req->acct);
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virtio_blk_free_request(req);
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}
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#ifdef __linux__
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typedef struct {
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VirtIOBlockReq *req;
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struct sg_io_hdr hdr;
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} VirtIOBlockIoctlReq;
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static void virtio_blk_ioctl_complete(void *opaque, int status)
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{
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VirtIOBlockIoctlReq *ioctl_req = opaque;
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VirtIOBlockReq *req = ioctl_req->req;
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VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
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struct virtio_scsi_inhdr *scsi;
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struct sg_io_hdr *hdr;
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scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base;
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if (status) {
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status = VIRTIO_BLK_S_UNSUPP;
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virtio_stl_p(vdev, &scsi->errors, 255);
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goto out;
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}
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hdr = &ioctl_req->hdr;
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/*
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* From SCSI-Generic-HOWTO: "Some lower level drivers (e.g. ide-scsi)
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* clear the masked_status field [hence status gets cleared too, see
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* block/scsi_ioctl.c] even when a CHECK_CONDITION or COMMAND_TERMINATED
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* status has occurred. However they do set DRIVER_SENSE in driver_status
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* field. Also a (sb_len_wr > 0) indicates there is a sense buffer.
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*/
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if (hdr->status == 0 && hdr->sb_len_wr > 0) {
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hdr->status = CHECK_CONDITION;
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}
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virtio_stl_p(vdev, &scsi->errors,
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hdr->status | (hdr->msg_status << 8) |
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(hdr->host_status << 16) | (hdr->driver_status << 24));
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virtio_stl_p(vdev, &scsi->residual, hdr->resid);
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virtio_stl_p(vdev, &scsi->sense_len, hdr->sb_len_wr);
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virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len);
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out:
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virtio_blk_req_complete(req, status);
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virtio_blk_free_request(req);
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g_free(ioctl_req);
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}
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#endif
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static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s)
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{
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VirtIOBlockReq *req = virtio_blk_alloc_request(s);
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if (!virtqueue_pop(s->vq, &req->elem)) {
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virtio_blk_free_request(req);
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return NULL;
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}
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return req;
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}
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static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req)
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{
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int status = VIRTIO_BLK_S_OK;
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struct virtio_scsi_inhdr *scsi = NULL;
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VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
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VirtQueueElement *elem = &req->elem;
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VirtIOBlock *blk = req->dev;
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#ifdef __linux__
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int i;
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VirtIOBlockIoctlReq *ioctl_req;
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BlockAIOCB *acb;
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#endif
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/*
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* We require at least one output segment each for the virtio_blk_outhdr
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* and the SCSI command block.
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*
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* We also at least require the virtio_blk_inhdr, the virtio_scsi_inhdr
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* and the sense buffer pointer in the input segments.
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*/
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if (elem->out_num < 2 || elem->in_num < 3) {
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status = VIRTIO_BLK_S_IOERR;
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goto fail;
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}
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/*
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* The scsi inhdr is placed in the second-to-last input segment, just
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* before the regular inhdr.
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*/
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scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base;
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if (!blk->conf.scsi) {
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status = VIRTIO_BLK_S_UNSUPP;
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goto fail;
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}
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/*
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* No support for bidirection commands yet.
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*/
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if (elem->out_num > 2 && elem->in_num > 3) {
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status = VIRTIO_BLK_S_UNSUPP;
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goto fail;
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}
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#ifdef __linux__
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ioctl_req = g_new0(VirtIOBlockIoctlReq, 1);
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ioctl_req->req = req;
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ioctl_req->hdr.interface_id = 'S';
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ioctl_req->hdr.cmd_len = elem->out_sg[1].iov_len;
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ioctl_req->hdr.cmdp = elem->out_sg[1].iov_base;
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ioctl_req->hdr.dxfer_len = 0;
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if (elem->out_num > 2) {
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/*
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* If there are more than the minimally required 2 output segments
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* there is write payload starting from the third iovec.
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*/
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ioctl_req->hdr.dxfer_direction = SG_DXFER_TO_DEV;
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ioctl_req->hdr.iovec_count = elem->out_num - 2;
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for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
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ioctl_req->hdr.dxfer_len += elem->out_sg[i + 2].iov_len;
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}
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ioctl_req->hdr.dxferp = elem->out_sg + 2;
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} else if (elem->in_num > 3) {
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/*
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* If we have more than 3 input segments the guest wants to actually
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* read data.
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*/
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ioctl_req->hdr.dxfer_direction = SG_DXFER_FROM_DEV;
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ioctl_req->hdr.iovec_count = elem->in_num - 3;
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for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
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ioctl_req->hdr.dxfer_len += elem->in_sg[i].iov_len;
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}
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ioctl_req->hdr.dxferp = elem->in_sg;
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} else {
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/*
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* Some SCSI commands don't actually transfer any data.
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*/
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ioctl_req->hdr.dxfer_direction = SG_DXFER_NONE;
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}
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ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base;
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ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len;
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acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr,
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virtio_blk_ioctl_complete, ioctl_req);
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if (!acb) {
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g_free(ioctl_req);
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status = VIRTIO_BLK_S_UNSUPP;
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goto fail;
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}
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return -EINPROGRESS;
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#else
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abort();
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#endif
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fail:
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/* Just put anything nonzero so that the ioctl fails in the guest. */
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if (scsi) {
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virtio_stl_p(vdev, &scsi->errors, 255);
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}
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return status;
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}
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static void virtio_blk_handle_scsi(VirtIOBlockReq *req)
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{
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int status;
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status = virtio_blk_handle_scsi_req(req);
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if (status != -EINPROGRESS) {
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virtio_blk_req_complete(req, status);
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virtio_blk_free_request(req);
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}
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}
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static inline void submit_requests(BlockBackend *blk, MultiReqBuffer *mrb,
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int start, int num_reqs, int niov)
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{
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QEMUIOVector *qiov = &mrb->reqs[start]->qiov;
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int64_t sector_num = mrb->reqs[start]->sector_num;
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int nb_sectors = mrb->reqs[start]->qiov.size / BDRV_SECTOR_SIZE;
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bool is_write = mrb->is_write;
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if (num_reqs > 1) {
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int i;
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struct iovec *tmp_iov = qiov->iov;
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int tmp_niov = qiov->niov;
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/* mrb->reqs[start]->qiov was initialized from external so we can't
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* modifiy it here. We need to initialize it locally and then add the
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* external iovecs. */
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qemu_iovec_init(qiov, niov);
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for (i = 0; i < tmp_niov; i++) {
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qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len);
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}
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for (i = start + 1; i < start + num_reqs; i++) {
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qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0,
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mrb->reqs[i]->qiov.size);
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mrb->reqs[i - 1]->mr_next = mrb->reqs[i];
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nb_sectors += mrb->reqs[i]->qiov.size / BDRV_SECTOR_SIZE;
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}
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assert(nb_sectors == qiov->size / BDRV_SECTOR_SIZE);
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trace_virtio_blk_submit_multireq(mrb, start, num_reqs, sector_num,
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nb_sectors, is_write);
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block_acct_merge_done(blk_get_stats(blk),
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is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ,
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num_reqs - 1);
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}
|
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if (is_write) {
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blk_aio_writev(blk, sector_num, qiov, nb_sectors,
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virtio_blk_rw_complete, mrb->reqs[start]);
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} else {
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blk_aio_readv(blk, sector_num, qiov, nb_sectors,
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virtio_blk_rw_complete, mrb->reqs[start]);
|
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}
|
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}
|
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|
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static int multireq_compare(const void *a, const void *b)
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{
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const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a,
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*req2 = *(VirtIOBlockReq **)b;
|
|
|
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/*
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* Note that we can't simply subtract sector_num1 from sector_num2
|
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* here as that could overflow the return value.
|
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*/
|
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if (req1->sector_num > req2->sector_num) {
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return 1;
|
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} else if (req1->sector_num < req2->sector_num) {
|
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return -1;
|
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} else {
|
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return 0;
|
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}
|
|
}
|
|
|
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void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb)
|
|
{
|
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int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0;
|
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int max_xfer_len = 0;
|
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int64_t sector_num = 0;
|
|
|
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if (mrb->num_reqs == 1) {
|
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submit_requests(blk, mrb, 0, 1, -1);
|
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mrb->num_reqs = 0;
|
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return;
|
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}
|
|
|
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max_xfer_len = blk_get_max_transfer_length(mrb->reqs[0]->dev->blk);
|
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max_xfer_len = MIN_NON_ZERO(max_xfer_len, BDRV_REQUEST_MAX_SECTORS);
|
|
|
|
qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs),
|
|
&multireq_compare);
|
|
|
|
for (i = 0; i < mrb->num_reqs; i++) {
|
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VirtIOBlockReq *req = mrb->reqs[i];
|
|
if (num_reqs > 0) {
|
|
bool merge = true;
|
|
|
|
/* merge would exceed maximum number of IOVs */
|
|
if (niov + req->qiov.niov > IOV_MAX) {
|
|
merge = false;
|
|
}
|
|
|
|
/* merge would exceed maximum transfer length of backend device */
|
|
if (req->qiov.size / BDRV_SECTOR_SIZE + nb_sectors > max_xfer_len) {
|
|
merge = false;
|
|
}
|
|
|
|
/* requests are not sequential */
|
|
if (sector_num + nb_sectors != req->sector_num) {
|
|
merge = false;
|
|
}
|
|
|
|
if (!merge) {
|
|
submit_requests(blk, 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(blk, mrb, start, num_reqs, niov);
|
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mrb->num_reqs = 0;
|
|
}
|
|
|
|
static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb)
|
|
{
|
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block_acct_start(blk_get_stats(req->dev->blk), &req->acct, 0,
|
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BLOCK_ACCT_FLUSH);
|
|
|
|
/*
|
|
* Make sure all outstanding writes are posted to the backing device.
|
|
*/
|
|
if (mrb->is_write && mrb->num_reqs > 0) {
|
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virtio_blk_submit_multireq(req->dev->blk, mrb);
|
|
}
|
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blk_aio_flush(req->dev->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;
|
|
}
|
|
|
|
void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
|
|
{
|
|
uint32_t type;
|
|
struct iovec *in_iov = req->elem.in_sg;
|
|
struct iovec *iov = req->elem.out_sg;
|
|
unsigned in_num = req->elem.in_num;
|
|
unsigned out_num = req->elem.out_num;
|
|
|
|
if (req->elem.out_num < 1 || req->elem.in_num < 1) {
|
|
error_report("virtio-blk missing headers");
|
|
exit(1);
|
|
}
|
|
|
|
if (unlikely(iov_to_buf(iov, out_num, 0, &req->out,
|
|
sizeof(req->out)) != sizeof(req->out))) {
|
|
error_report("virtio-blk request outhdr too short");
|
|
exit(1);
|
|
}
|
|
|
|
iov_discard_front(&iov, &out_num, sizeof(req->out));
|
|
|
|
if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
|
|
error_report("virtio-blk request inhdr too short");
|
|
exit(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(in_iov, &in_num, sizeof(struct virtio_blk_inhdr));
|
|
|
|
type = virtio_ldl_p(VIRTIO_DEVICE(req->dev), &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(VIRTIO_DEVICE(req->dev),
|
|
&req->out.sector);
|
|
|
|
if (is_write) {
|
|
qemu_iovec_init_external(&req->qiov, iov, out_num);
|
|
trace_virtio_blk_handle_write(req, req->sector_num,
|
|
req->qiov.size / BDRV_SECTOR_SIZE);
|
|
} else {
|
|
qemu_iovec_init_external(&req->qiov, in_iov, in_num);
|
|
trace_virtio_blk_handle_read(req, req->sector_num,
|
|
req->qiov.size / BDRV_SECTOR_SIZE);
|
|
}
|
|
|
|
if (!virtio_blk_sect_range_ok(req->dev, req->sector_num,
|
|
req->qiov.size)) {
|
|
virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
|
|
block_acct_invalid(blk_get_stats(req->dev->blk),
|
|
is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
|
|
virtio_blk_free_request(req);
|
|
return;
|
|
}
|
|
|
|
block_acct_start(blk_get_stats(req->dev->blk),
|
|
&req->acct, req->qiov.size,
|
|
is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
|
|
|
|
/* merge would exceed maximum number of requests or IO direction
|
|
* changes */
|
|
if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS ||
|
|
is_write != mrb->is_write ||
|
|
!req->dev->conf.request_merging)) {
|
|
virtio_blk_submit_multireq(req->dev->blk, mrb);
|
|
}
|
|
|
|
assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS);
|
|
mrb->reqs[mrb->num_reqs++] = req;
|
|
mrb->is_write = is_write;
|
|
break;
|
|
}
|
|
case VIRTIO_BLK_T_FLUSH:
|
|
virtio_blk_handle_flush(req, mrb);
|
|
break;
|
|
case VIRTIO_BLK_T_SCSI_CMD:
|
|
virtio_blk_handle_scsi(req);
|
|
break;
|
|
case VIRTIO_BLK_T_GET_ID:
|
|
{
|
|
VirtIOBlock *s = req->dev;
|
|
|
|
/*
|
|
* NB: per existing s/n string convention the string is
|
|
* terminated by '\0' only when shorter than buffer.
|
|
*/
|
|
const char *serial = s->conf.serial ? s->conf.serial : "";
|
|
size_t size = MIN(strlen(serial) + 1,
|
|
MIN(iov_size(in_iov, in_num),
|
|
VIRTIO_BLK_ID_BYTES));
|
|
iov_from_buf(in_iov, in_num, 0, serial, size);
|
|
virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
|
|
virtio_blk_free_request(req);
|
|
break;
|
|
}
|
|
default:
|
|
virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
|
|
virtio_blk_free_request(req);
|
|
}
|
|
}
|
|
|
|
static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
VirtIOBlockReq *req;
|
|
MultiReqBuffer mrb = {};
|
|
|
|
/* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
|
|
* dataplane here instead of waiting for .set_status().
|
|
*/
|
|
if (s->dataplane) {
|
|
virtio_blk_data_plane_start(s->dataplane);
|
|
return;
|
|
}
|
|
|
|
blk_io_plug(s->blk);
|
|
|
|
while ((req = virtio_blk_get_request(s))) {
|
|
virtio_blk_handle_request(req, &mrb);
|
|
}
|
|
|
|
if (mrb.num_reqs) {
|
|
virtio_blk_submit_multireq(s->blk, &mrb);
|
|
}
|
|
|
|
blk_io_unplug(s->blk);
|
|
}
|
|
|
|
static void virtio_blk_dma_restart_bh(void *opaque)
|
|
{
|
|
VirtIOBlock *s = opaque;
|
|
VirtIOBlockReq *req = s->rq;
|
|
MultiReqBuffer mrb = {};
|
|
|
|
qemu_bh_delete(s->bh);
|
|
s->bh = NULL;
|
|
|
|
s->rq = NULL;
|
|
|
|
while (req) {
|
|
VirtIOBlockReq *next = req->next;
|
|
virtio_blk_handle_request(req, &mrb);
|
|
req = next;
|
|
}
|
|
|
|
if (mrb.num_reqs) {
|
|
virtio_blk_submit_multireq(s->blk, &mrb);
|
|
}
|
|
}
|
|
|
|
static void virtio_blk_dma_restart_cb(void *opaque, int running,
|
|
RunState state)
|
|
{
|
|
VirtIOBlock *s = opaque;
|
|
|
|
if (!running) {
|
|
return;
|
|
}
|
|
|
|
if (!s->bh) {
|
|
s->bh = aio_bh_new(blk_get_aio_context(s->conf.conf.blk),
|
|
virtio_blk_dma_restart_bh, s);
|
|
qemu_bh_schedule(s->bh);
|
|
}
|
|
}
|
|
|
|
static void virtio_blk_reset(VirtIODevice *vdev)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
AioContext *ctx;
|
|
|
|
/*
|
|
* This should cancel pending requests, but can't do nicely until there
|
|
* are per-device request lists.
|
|
*/
|
|
ctx = blk_get_aio_context(s->blk);
|
|
aio_context_acquire(ctx);
|
|
blk_drain(s->blk);
|
|
|
|
if (s->dataplane) {
|
|
virtio_blk_data_plane_stop(s->dataplane);
|
|
}
|
|
aio_context_release(ctx);
|
|
|
|
blk_set_enable_write_cache(s->blk, s->original_wce);
|
|
}
|
|
|
|
/* coalesce internal state, copy to pci i/o region 0
|
|
*/
|
|
static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
BlockConf *conf = &s->conf.conf;
|
|
struct virtio_blk_config blkcfg;
|
|
uint64_t capacity;
|
|
int blk_size = conf->logical_block_size;
|
|
|
|
blk_get_geometry(s->blk, &capacity);
|
|
memset(&blkcfg, 0, sizeof(blkcfg));
|
|
virtio_stq_p(vdev, &blkcfg.capacity, capacity);
|
|
virtio_stl_p(vdev, &blkcfg.seg_max, 128 - 2);
|
|
virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls);
|
|
virtio_stl_p(vdev, &blkcfg.blk_size, blk_size);
|
|
virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size);
|
|
virtio_stw_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size);
|
|
blkcfg.geometry.heads = conf->heads;
|
|
/*
|
|
* We must ensure that the block device capacity is a multiple of
|
|
* the logical block size. If that is not the case, let's use
|
|
* sector_mask to adopt the geometry to have a correct picture.
|
|
* For those devices where the capacity is ok for the given geometry
|
|
* we don't touch the sector value of the geometry, since some devices
|
|
* (like s390 dasd) need a specific value. Here the capacity is already
|
|
* cyls*heads*secs*blk_size and the sector value is not block size
|
|
* divided by 512 - instead it is the amount of blk_size blocks
|
|
* per track (cylinder).
|
|
*/
|
|
if (blk_getlength(s->blk) / conf->heads / conf->secs % blk_size) {
|
|
blkcfg.geometry.sectors = conf->secs & ~s->sector_mask;
|
|
} else {
|
|
blkcfg.geometry.sectors = conf->secs;
|
|
}
|
|
blkcfg.size_max = 0;
|
|
blkcfg.physical_block_exp = get_physical_block_exp(conf);
|
|
blkcfg.alignment_offset = 0;
|
|
blkcfg.wce = blk_enable_write_cache(s->blk);
|
|
memcpy(config, &blkcfg, sizeof(struct virtio_blk_config));
|
|
}
|
|
|
|
static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
struct virtio_blk_config blkcfg;
|
|
|
|
memcpy(&blkcfg, config, sizeof(blkcfg));
|
|
|
|
aio_context_acquire(blk_get_aio_context(s->blk));
|
|
blk_set_enable_write_cache(s->blk, blkcfg.wce != 0);
|
|
aio_context_release(blk_get_aio_context(s->blk));
|
|
}
|
|
|
|
static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features,
|
|
Error **errp)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
|
|
virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX);
|
|
virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY);
|
|
virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY);
|
|
virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE);
|
|
if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) {
|
|
if (s->conf.scsi) {
|
|
error_setg(errp, "Please set scsi=off for virtio-blk devices in order to use virtio 1.0");
|
|
return 0;
|
|
}
|
|
} else {
|
|
virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT);
|
|
virtio_add_feature(&features, VIRTIO_BLK_F_SCSI);
|
|
}
|
|
|
|
if (s->conf.config_wce) {
|
|
virtio_add_feature(&features, VIRTIO_BLK_F_CONFIG_WCE);
|
|
}
|
|
if (blk_enable_write_cache(s->blk)) {
|
|
virtio_add_feature(&features, VIRTIO_BLK_F_WCE);
|
|
}
|
|
if (blk_is_read_only(s->blk)) {
|
|
virtio_add_feature(&features, VIRTIO_BLK_F_RO);
|
|
}
|
|
|
|
return features;
|
|
}
|
|
|
|
static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
|
|
if (s->dataplane && !(status & (VIRTIO_CONFIG_S_DRIVER |
|
|
VIRTIO_CONFIG_S_DRIVER_OK))) {
|
|
virtio_blk_data_plane_stop(s->dataplane);
|
|
}
|
|
|
|
if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
|
|
return;
|
|
}
|
|
|
|
/* A guest that supports VIRTIO_BLK_F_CONFIG_WCE must be able to send
|
|
* cache flushes. Thus, the "auto writethrough" behavior is never
|
|
* necessary for guests that support the VIRTIO_BLK_F_CONFIG_WCE feature.
|
|
* Leaving it enabled would break the following sequence:
|
|
*
|
|
* Guest started with "-drive cache=writethrough"
|
|
* Guest sets status to 0
|
|
* Guest sets DRIVER bit in status field
|
|
* Guest reads host features (WCE=0, CONFIG_WCE=1)
|
|
* Guest writes guest features (WCE=0, CONFIG_WCE=1)
|
|
* Guest writes 1 to the WCE configuration field (writeback mode)
|
|
* Guest sets DRIVER_OK bit in status field
|
|
*
|
|
* s->blk would erroneously be placed in writethrough mode.
|
|
*/
|
|
if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) {
|
|
aio_context_acquire(blk_get_aio_context(s->blk));
|
|
blk_set_enable_write_cache(s->blk,
|
|
virtio_vdev_has_feature(vdev,
|
|
VIRTIO_BLK_F_WCE));
|
|
aio_context_release(blk_get_aio_context(s->blk));
|
|
}
|
|
}
|
|
|
|
static void virtio_blk_save(QEMUFile *f, void *opaque)
|
|
{
|
|
VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
|
|
if (s->dataplane) {
|
|
virtio_blk_data_plane_stop(s->dataplane);
|
|
}
|
|
|
|
virtio_save(vdev, f);
|
|
}
|
|
|
|
static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
VirtIOBlockReq *req = s->rq;
|
|
|
|
while (req) {
|
|
qemu_put_sbyte(f, 1);
|
|
qemu_put_buffer(f, (unsigned char *)&req->elem,
|
|
sizeof(VirtQueueElement));
|
|
req = req->next;
|
|
}
|
|
qemu_put_sbyte(f, 0);
|
|
}
|
|
|
|
static int virtio_blk_load(QEMUFile *f, void *opaque, int version_id)
|
|
{
|
|
VirtIOBlock *s = opaque;
|
|
VirtIODevice *vdev = VIRTIO_DEVICE(s);
|
|
|
|
if (version_id != 2)
|
|
return -EINVAL;
|
|
|
|
return virtio_load(vdev, f, version_id);
|
|
}
|
|
|
|
static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f,
|
|
int version_id)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
|
|
while (qemu_get_sbyte(f)) {
|
|
VirtIOBlockReq *req = virtio_blk_alloc_request(s);
|
|
qemu_get_buffer(f, (unsigned char *)&req->elem,
|
|
sizeof(VirtQueueElement));
|
|
req->next = s->rq;
|
|
s->rq = req;
|
|
|
|
virtqueue_map(&req->elem);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void virtio_blk_resize(void *opaque)
|
|
{
|
|
VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
|
|
|
|
virtio_notify_config(vdev);
|
|
}
|
|
|
|
static const BlockDevOps virtio_block_ops = {
|
|
.resize_cb = virtio_blk_resize,
|
|
};
|
|
|
|
/* Disable dataplane thread during live migration since it does not
|
|
* update the dirty memory bitmap yet.
|
|
*/
|
|
static void virtio_blk_migration_state_changed(Notifier *notifier, void *data)
|
|
{
|
|
VirtIOBlock *s = container_of(notifier, VirtIOBlock,
|
|
migration_state_notifier);
|
|
MigrationState *mig = data;
|
|
Error *err = NULL;
|
|
|
|
if (migration_in_setup(mig)) {
|
|
if (!s->dataplane) {
|
|
return;
|
|
}
|
|
virtio_blk_data_plane_destroy(s->dataplane);
|
|
s->dataplane = NULL;
|
|
} else if (migration_has_finished(mig) ||
|
|
migration_has_failed(mig)) {
|
|
if (s->dataplane) {
|
|
return;
|
|
}
|
|
blk_drain_all(); /* complete in-flight non-dataplane requests */
|
|
virtio_blk_data_plane_create(VIRTIO_DEVICE(s), &s->conf,
|
|
&s->dataplane, &err);
|
|
if (err != NULL) {
|
|
error_report_err(err);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
|
|
{
|
|
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
|
|
VirtIOBlock *s = VIRTIO_BLK(dev);
|
|
VirtIOBlkConf *conf = &s->conf;
|
|
Error *err = NULL;
|
|
static int virtio_blk_id;
|
|
|
|
if (!conf->conf.blk) {
|
|
error_setg(errp, "drive property not set");
|
|
return;
|
|
}
|
|
if (!blk_is_inserted(conf->conf.blk)) {
|
|
error_setg(errp, "Device needs media, but drive is empty");
|
|
return;
|
|
}
|
|
|
|
blkconf_serial(&conf->conf, &conf->serial);
|
|
s->original_wce = blk_enable_write_cache(conf->conf.blk);
|
|
blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, &err);
|
|
if (err) {
|
|
error_propagate(errp, err);
|
|
return;
|
|
}
|
|
blkconf_blocksizes(&conf->conf);
|
|
|
|
virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK,
|
|
sizeof(struct virtio_blk_config));
|
|
|
|
s->blk = conf->conf.blk;
|
|
s->rq = NULL;
|
|
s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1;
|
|
|
|
s->vq = virtio_add_queue(vdev, 128, virtio_blk_handle_output);
|
|
s->complete_request = virtio_blk_complete_request;
|
|
virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err);
|
|
if (err != NULL) {
|
|
error_propagate(errp, err);
|
|
virtio_cleanup(vdev);
|
|
return;
|
|
}
|
|
s->migration_state_notifier.notify = virtio_blk_migration_state_changed;
|
|
add_migration_state_change_notifier(&s->migration_state_notifier);
|
|
|
|
s->change = qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s);
|
|
register_savevm(dev, "virtio-blk", virtio_blk_id++, 2,
|
|
virtio_blk_save, virtio_blk_load, s);
|
|
blk_set_dev_ops(s->blk, &virtio_block_ops, s);
|
|
blk_set_guest_block_size(s->blk, s->conf.conf.logical_block_size);
|
|
|
|
blk_iostatus_enable(s->blk);
|
|
}
|
|
|
|
static void virtio_blk_device_unrealize(DeviceState *dev, Error **errp)
|
|
{
|
|
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
|
|
VirtIOBlock *s = VIRTIO_BLK(dev);
|
|
|
|
remove_migration_state_change_notifier(&s->migration_state_notifier);
|
|
virtio_blk_data_plane_destroy(s->dataplane);
|
|
s->dataplane = NULL;
|
|
qemu_del_vm_change_state_handler(s->change);
|
|
unregister_savevm(dev, "virtio-blk", s);
|
|
blockdev_mark_auto_del(s->blk);
|
|
virtio_cleanup(vdev);
|
|
}
|
|
|
|
static void virtio_blk_instance_init(Object *obj)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(obj);
|
|
|
|
object_property_add_link(obj, "iothread", TYPE_IOTHREAD,
|
|
(Object **)&s->conf.iothread,
|
|
qdev_prop_allow_set_link_before_realize,
|
|
OBJ_PROP_LINK_UNREF_ON_RELEASE, NULL);
|
|
device_add_bootindex_property(obj, &s->conf.conf.bootindex,
|
|
"bootindex", "/disk@0,0",
|
|
DEVICE(obj), NULL);
|
|
}
|
|
|
|
static Property virtio_blk_properties[] = {
|
|
DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf),
|
|
DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf),
|
|
DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial),
|
|
DEFINE_PROP_BIT("config-wce", VirtIOBlock, conf.config_wce, 0, true),
|
|
#ifdef __linux__
|
|
DEFINE_PROP_BIT("scsi", VirtIOBlock, conf.scsi, 0, false),
|
|
#endif
|
|
DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0,
|
|
true),
|
|
DEFINE_PROP_BIT("x-data-plane", VirtIOBlock, conf.data_plane, 0, false),
|
|
DEFINE_PROP_END_OF_LIST(),
|
|
};
|
|
|
|
static void virtio_blk_class_init(ObjectClass *klass, void *data)
|
|
{
|
|
DeviceClass *dc = DEVICE_CLASS(klass);
|
|
VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
|
|
|
|
dc->props = virtio_blk_properties;
|
|
set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
|
|
vdc->realize = virtio_blk_device_realize;
|
|
vdc->unrealize = virtio_blk_device_unrealize;
|
|
vdc->get_config = virtio_blk_update_config;
|
|
vdc->set_config = virtio_blk_set_config;
|
|
vdc->get_features = virtio_blk_get_features;
|
|
vdc->set_status = virtio_blk_set_status;
|
|
vdc->reset = virtio_blk_reset;
|
|
vdc->save = virtio_blk_save_device;
|
|
vdc->load = virtio_blk_load_device;
|
|
}
|
|
|
|
static const TypeInfo virtio_device_info = {
|
|
.name = TYPE_VIRTIO_BLK,
|
|
.parent = TYPE_VIRTIO_DEVICE,
|
|
.instance_size = sizeof(VirtIOBlock),
|
|
.instance_init = virtio_blk_instance_init,
|
|
.class_init = virtio_blk_class_init,
|
|
};
|
|
|
|
static void virtio_register_types(void)
|
|
{
|
|
type_register_static(&virtio_device_info);
|
|
}
|
|
|
|
type_init(virtio_register_types)
|