The following sequence happens: - the SeaBIOS virtio-blk driver does not support the WCE feature, which causes QEMU to disable writeback caching - the Linux virtio-blk driver resets the device, finds WCE is available but writeback caching is disabled; tells block layer to not send cache flush commands - the Linux virtio-blk driver sets the DRIVER_OK bit, which causes writeback caching to be re-enabled, but the Linux virtio-blk driver does not know of this side effect and cache flushes remain disabled The bug is at the third step. If the guest does know about CONFIG_WCE, QEMU should ignore the WCE feature's state. The guest will control the cache mode solely using configuration space. This change makes Linux do flushes correctly, but Linux will keep SeaBIOS's writethrough mode. Hence, whenever the guest is reset, the cache mode of the disk should be reset to whatever was specified in the "-drive" option. With this change, the Linux virtio-blk driver finds that writeback caching is enabled, and tells the block layer to send cache flush commands appropriately. Reported-by: Rusty Russell <rusty@au1.ibm.com Cc: qemu-stable@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
781 lines
22 KiB
C
781 lines
22 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/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/blockdev.h"
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#include "hw/virtio/virtio-blk.h"
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#ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
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# include "dataplane/virtio-blk.h"
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# include "migration/migration.h"
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#endif
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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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typedef struct VirtIOBlockReq
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{
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VirtIOBlock *dev;
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VirtQueueElement elem;
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struct virtio_blk_inhdr *in;
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struct virtio_blk_outhdr *out;
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struct virtio_scsi_inhdr *scsi;
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QEMUIOVector qiov;
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struct VirtIOBlockReq *next;
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BlockAcctCookie acct;
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} VirtIOBlockReq;
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static void virtio_blk_req_complete(VirtIOBlockReq *req, int 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->qiov.size + sizeof(*req->in));
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virtio_notify(vdev, s->vq);
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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 = bdrv_get_error_action(req->dev->bs, is_read, error);
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VirtIOBlock *s = req->dev;
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if (action == BDRV_ACTION_STOP) {
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req->next = s->rq;
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s->rq = req;
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} else if (action == BDRV_ACTION_REPORT) {
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virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
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bdrv_acct_done(s->bs, &req->acct);
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g_free(req);
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}
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bdrv_error_action(s->bs, action, is_read, error);
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return action != BDRV_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 *req = opaque;
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trace_virtio_blk_rw_complete(req, ret);
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if (ret) {
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bool is_read = !(ldl_p(&req->out->type) & VIRTIO_BLK_T_OUT);
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if (virtio_blk_handle_rw_error(req, -ret, is_read))
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return;
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}
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virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
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bdrv_acct_done(req->dev->bs, &req->acct);
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g_free(req);
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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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bdrv_acct_done(req->dev->bs, &req->acct);
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g_free(req);
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}
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static VirtIOBlockReq *virtio_blk_alloc_request(VirtIOBlock *s)
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{
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VirtIOBlockReq *req = g_malloc(sizeof(*req));
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req->dev = s;
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req->qiov.size = 0;
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req->next = NULL;
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return req;
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}
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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 (req != NULL) {
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if (!virtqueue_pop(s->vq, &req->elem)) {
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g_free(req);
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return NULL;
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}
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}
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return req;
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}
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static void virtio_blk_handle_scsi(VirtIOBlockReq *req)
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{
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#ifdef __linux__
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int ret;
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int i;
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#endif
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int status = VIRTIO_BLK_S_OK;
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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 (req->elem.out_num < 2 || req->elem.in_num < 3) {
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virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
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g_free(req);
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return;
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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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req->scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base;
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if (!req->dev->blk.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 (req->elem.out_num > 2 && req->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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struct sg_io_hdr hdr;
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memset(&hdr, 0, sizeof(struct sg_io_hdr));
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hdr.interface_id = 'S';
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hdr.cmd_len = req->elem.out_sg[1].iov_len;
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hdr.cmdp = req->elem.out_sg[1].iov_base;
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hdr.dxfer_len = 0;
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if (req->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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hdr.dxfer_direction = SG_DXFER_TO_DEV;
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hdr.iovec_count = req->elem.out_num - 2;
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for (i = 0; i < hdr.iovec_count; i++)
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hdr.dxfer_len += req->elem.out_sg[i + 2].iov_len;
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hdr.dxferp = req->elem.out_sg + 2;
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} else if (req->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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hdr.dxfer_direction = SG_DXFER_FROM_DEV;
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hdr.iovec_count = req->elem.in_num - 3;
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for (i = 0; i < hdr.iovec_count; i++)
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hdr.dxfer_len += req->elem.in_sg[i].iov_len;
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hdr.dxferp = req->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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hdr.dxfer_direction = SG_DXFER_NONE;
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}
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hdr.sbp = req->elem.in_sg[req->elem.in_num - 3].iov_base;
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hdr.mx_sb_len = req->elem.in_sg[req->elem.in_num - 3].iov_len;
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ret = bdrv_ioctl(req->dev->bs, SG_IO, &hdr);
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if (ret) {
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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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* 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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stl_p(&req->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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stl_p(&req->scsi->residual, hdr.resid);
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stl_p(&req->scsi->sense_len, hdr.sb_len_wr);
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stl_p(&req->scsi->data_len, hdr.dxfer_len);
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virtio_blk_req_complete(req, status);
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g_free(req);
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return;
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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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stl_p(&req->scsi->errors, 255);
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virtio_blk_req_complete(req, status);
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g_free(req);
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}
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typedef struct MultiReqBuffer {
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BlockRequest blkreq[32];
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unsigned int num_writes;
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} MultiReqBuffer;
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static void virtio_submit_multiwrite(BlockDriverState *bs, MultiReqBuffer *mrb)
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{
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int i, ret;
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if (!mrb->num_writes) {
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return;
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}
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ret = bdrv_aio_multiwrite(bs, mrb->blkreq, mrb->num_writes);
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if (ret != 0) {
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for (i = 0; i < mrb->num_writes; i++) {
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if (mrb->blkreq[i].error) {
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virtio_blk_rw_complete(mrb->blkreq[i].opaque, -EIO);
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}
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}
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}
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mrb->num_writes = 0;
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}
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static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb)
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{
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bdrv_acct_start(req->dev->bs, &req->acct, 0, BDRV_ACCT_FLUSH);
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/*
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* Make sure all outstanding writes are posted to the backing device.
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*/
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virtio_submit_multiwrite(req->dev->bs, mrb);
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bdrv_aio_flush(req->dev->bs, virtio_blk_flush_complete, req);
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}
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static void virtio_blk_handle_write(VirtIOBlockReq *req, MultiReqBuffer *mrb)
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{
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BlockRequest *blkreq;
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uint64_t sector;
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sector = ldq_p(&req->out->sector);
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bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_WRITE);
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trace_virtio_blk_handle_write(req, sector, req->qiov.size / 512);
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if (sector & req->dev->sector_mask) {
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virtio_blk_rw_complete(req, -EIO);
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return;
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}
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if (req->qiov.size % req->dev->conf->logical_block_size) {
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virtio_blk_rw_complete(req, -EIO);
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return;
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}
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if (mrb->num_writes == 32) {
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virtio_submit_multiwrite(req->dev->bs, mrb);
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}
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blkreq = &mrb->blkreq[mrb->num_writes];
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blkreq->sector = sector;
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blkreq->nb_sectors = req->qiov.size / BDRV_SECTOR_SIZE;
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blkreq->qiov = &req->qiov;
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blkreq->cb = virtio_blk_rw_complete;
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blkreq->opaque = req;
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blkreq->error = 0;
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mrb->num_writes++;
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}
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static void virtio_blk_handle_read(VirtIOBlockReq *req)
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{
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uint64_t sector;
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sector = ldq_p(&req->out->sector);
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bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_READ);
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trace_virtio_blk_handle_read(req, sector, req->qiov.size / 512);
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if (sector & req->dev->sector_mask) {
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virtio_blk_rw_complete(req, -EIO);
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return;
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}
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if (req->qiov.size % req->dev->conf->logical_block_size) {
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virtio_blk_rw_complete(req, -EIO);
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return;
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}
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bdrv_aio_readv(req->dev->bs, sector, &req->qiov,
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req->qiov.size / BDRV_SECTOR_SIZE,
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virtio_blk_rw_complete, req);
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}
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static void virtio_blk_handle_request(VirtIOBlockReq *req,
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MultiReqBuffer *mrb)
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{
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uint32_t type;
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if (req->elem.out_num < 1 || req->elem.in_num < 1) {
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error_report("virtio-blk missing headers");
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exit(1);
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}
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if (req->elem.out_sg[0].iov_len < sizeof(*req->out) ||
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req->elem.in_sg[req->elem.in_num - 1].iov_len < sizeof(*req->in)) {
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error_report("virtio-blk header not in correct element");
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exit(1);
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}
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req->out = (void *)req->elem.out_sg[0].iov_base;
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req->in = (void *)req->elem.in_sg[req->elem.in_num - 1].iov_base;
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type = ldl_p(&req->out->type);
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if (type & VIRTIO_BLK_T_FLUSH) {
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virtio_blk_handle_flush(req, mrb);
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} else if (type & VIRTIO_BLK_T_SCSI_CMD) {
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virtio_blk_handle_scsi(req);
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} else if (type & VIRTIO_BLK_T_GET_ID) {
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VirtIOBlock *s = req->dev;
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/*
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* NB: per existing s/n string convention the string is
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* terminated by '\0' only when shorter than buffer.
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*/
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strncpy(req->elem.in_sg[0].iov_base,
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s->blk.serial ? s->blk.serial : "",
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MIN(req->elem.in_sg[0].iov_len, VIRTIO_BLK_ID_BYTES));
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virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
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g_free(req);
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} else if (type & VIRTIO_BLK_T_OUT) {
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qemu_iovec_init_external(&req->qiov, &req->elem.out_sg[1],
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req->elem.out_num - 1);
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virtio_blk_handle_write(req, mrb);
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} else if (type == VIRTIO_BLK_T_IN || type == VIRTIO_BLK_T_BARRIER) {
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/* VIRTIO_BLK_T_IN is 0, so we can't just & it. */
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qemu_iovec_init_external(&req->qiov, &req->elem.in_sg[0],
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req->elem.in_num - 1);
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virtio_blk_handle_read(req);
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} else {
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virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
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g_free(req);
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}
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}
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static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
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{
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VirtIOBlock *s = VIRTIO_BLK(vdev);
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VirtIOBlockReq *req;
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MultiReqBuffer mrb = {
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.num_writes = 0,
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};
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#ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
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/* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
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* dataplane here instead of waiting for .set_status().
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*/
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if (s->dataplane) {
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virtio_blk_data_plane_start(s->dataplane);
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return;
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}
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#endif
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while ((req = virtio_blk_get_request(s))) {
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virtio_blk_handle_request(req, &mrb);
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}
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virtio_submit_multiwrite(s->bs, &mrb);
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/*
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* FIXME: Want to check for completions before returning to guest mode,
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* so cached reads and writes are reported as quickly as possible. But
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* that should be done in the generic block layer.
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*/
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}
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static void virtio_blk_dma_restart_bh(void *opaque)
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{
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VirtIOBlock *s = opaque;
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VirtIOBlockReq *req = s->rq;
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MultiReqBuffer mrb = {
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.num_writes = 0,
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};
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qemu_bh_delete(s->bh);
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s->bh = NULL;
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s->rq = NULL;
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while (req) {
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virtio_blk_handle_request(req, &mrb);
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req = req->next;
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}
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virtio_submit_multiwrite(s->bs, &mrb);
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}
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static void virtio_blk_dma_restart_cb(void *opaque, int running,
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RunState state)
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{
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VirtIOBlock *s = opaque;
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if (!running) {
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return;
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}
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if (!s->bh) {
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s->bh = qemu_bh_new(virtio_blk_dma_restart_bh, s);
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qemu_bh_schedule(s->bh);
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}
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}
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static void virtio_blk_reset(VirtIODevice *vdev)
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{
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VirtIOBlock *s = VIRTIO_BLK(vdev);
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#ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
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if (s->dataplane) {
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virtio_blk_data_plane_stop(s->dataplane);
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}
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#endif
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/*
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* This should cancel pending requests, but can't do nicely until there
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* are per-device request lists.
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*/
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bdrv_drain_all();
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bdrv_set_enable_write_cache(s->bs, s->original_wce);
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}
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|
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/* 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);
|
|
struct virtio_blk_config blkcfg;
|
|
uint64_t capacity;
|
|
int blk_size = s->conf->logical_block_size;
|
|
|
|
bdrv_get_geometry(s->bs, &capacity);
|
|
memset(&blkcfg, 0, sizeof(blkcfg));
|
|
stq_raw(&blkcfg.capacity, capacity);
|
|
stl_raw(&blkcfg.seg_max, 128 - 2);
|
|
stw_raw(&blkcfg.cylinders, s->conf->cyls);
|
|
stl_raw(&blkcfg.blk_size, blk_size);
|
|
stw_raw(&blkcfg.min_io_size, s->conf->min_io_size / blk_size);
|
|
stw_raw(&blkcfg.opt_io_size, s->conf->opt_io_size / blk_size);
|
|
blkcfg.heads = s->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 (bdrv_getlength(s->bs) / s->conf->heads / s->conf->secs % blk_size) {
|
|
blkcfg.sectors = s->conf->secs & ~s->sector_mask;
|
|
} else {
|
|
blkcfg.sectors = s->conf->secs;
|
|
}
|
|
blkcfg.size_max = 0;
|
|
blkcfg.physical_block_exp = get_physical_block_exp(s->conf);
|
|
blkcfg.alignment_offset = 0;
|
|
blkcfg.wce = bdrv_enable_write_cache(s->bs);
|
|
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));
|
|
bdrv_set_enable_write_cache(s->bs, blkcfg.wce != 0);
|
|
}
|
|
|
|
static uint32_t virtio_blk_get_features(VirtIODevice *vdev, uint32_t features)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
|
|
features |= (1 << VIRTIO_BLK_F_SEG_MAX);
|
|
features |= (1 << VIRTIO_BLK_F_GEOMETRY);
|
|
features |= (1 << VIRTIO_BLK_F_TOPOLOGY);
|
|
features |= (1 << VIRTIO_BLK_F_BLK_SIZE);
|
|
features |= (1 << VIRTIO_BLK_F_SCSI);
|
|
|
|
if (s->blk.config_wce) {
|
|
features |= (1 << VIRTIO_BLK_F_CONFIG_WCE);
|
|
}
|
|
if (bdrv_enable_write_cache(s->bs))
|
|
features |= (1 << VIRTIO_BLK_F_WCE);
|
|
|
|
if (bdrv_is_read_only(s->bs))
|
|
features |= 1 << VIRTIO_BLK_F_RO;
|
|
|
|
return features;
|
|
}
|
|
|
|
static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
uint32_t features;
|
|
|
|
#ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
|
|
if (s->dataplane && !(status & (VIRTIO_CONFIG_S_DRIVER |
|
|
VIRTIO_CONFIG_S_DRIVER_OK))) {
|
|
virtio_blk_data_plane_stop(s->dataplane);
|
|
}
|
|
#endif
|
|
|
|
if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
|
|
return;
|
|
}
|
|
|
|
features = vdev->guest_features;
|
|
|
|
/* 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->bs would erroneously be placed in writethrough mode.
|
|
*/
|
|
if (!(features & (1 << VIRTIO_BLK_F_CONFIG_WCE))) {
|
|
bdrv_set_enable_write_cache(s->bs, !!(features & (1 << VIRTIO_BLK_F_WCE)));
|
|
}
|
|
}
|
|
|
|
static void virtio_blk_save(QEMUFile *f, void *opaque)
|
|
{
|
|
VirtIOBlock *s = opaque;
|
|
VirtIODevice *vdev = VIRTIO_DEVICE(s);
|
|
VirtIOBlockReq *req = s->rq;
|
|
|
|
virtio_save(vdev, f);
|
|
|
|
while (req) {
|
|
qemu_put_sbyte(f, 1);
|
|
qemu_put_buffer(f, (unsigned char*)&req->elem, sizeof(req->elem));
|
|
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);
|
|
int ret;
|
|
|
|
if (version_id != 2)
|
|
return -EINVAL;
|
|
|
|
ret = virtio_load(vdev, f);
|
|
if (ret) {
|
|
return ret;
|
|
}
|
|
|
|
while (qemu_get_sbyte(f)) {
|
|
VirtIOBlockReq *req = virtio_blk_alloc_request(s);
|
|
qemu_get_buffer(f, (unsigned char*)&req->elem, sizeof(req->elem));
|
|
req->next = s->rq;
|
|
s->rq = req;
|
|
|
|
virtqueue_map_sg(req->elem.in_sg, req->elem.in_addr,
|
|
req->elem.in_num, 1);
|
|
virtqueue_map_sg(req->elem.out_sg, req->elem.out_addr,
|
|
req->elem.out_num, 0);
|
|
}
|
|
|
|
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,
|
|
};
|
|
|
|
void virtio_blk_set_conf(DeviceState *dev, VirtIOBlkConf *blk)
|
|
{
|
|
VirtIOBlock *s = VIRTIO_BLK(dev);
|
|
memcpy(&(s->blk), blk, sizeof(struct VirtIOBlkConf));
|
|
}
|
|
|
|
#ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
|
|
/* 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;
|
|
|
|
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;
|
|
}
|
|
bdrv_drain_all(); /* complete in-flight non-dataplane requests */
|
|
virtio_blk_data_plane_create(VIRTIO_DEVICE(s), &s->blk,
|
|
&s->dataplane);
|
|
}
|
|
}
|
|
#endif /* CONFIG_VIRTIO_BLK_DATA_PLANE */
|
|
|
|
static int virtio_blk_device_init(VirtIODevice *vdev)
|
|
{
|
|
DeviceState *qdev = DEVICE(vdev);
|
|
VirtIOBlock *s = VIRTIO_BLK(vdev);
|
|
VirtIOBlkConf *blk = &(s->blk);
|
|
static int virtio_blk_id;
|
|
|
|
if (!blk->conf.bs) {
|
|
error_report("drive property not set");
|
|
return -1;
|
|
}
|
|
if (!bdrv_is_inserted(blk->conf.bs)) {
|
|
error_report("Device needs media, but drive is empty");
|
|
return -1;
|
|
}
|
|
|
|
blkconf_serial(&blk->conf, &blk->serial);
|
|
s->original_wce = bdrv_enable_write_cache(blk->conf.bs);
|
|
if (blkconf_geometry(&blk->conf, NULL, 65535, 255, 255) < 0) {
|
|
return -1;
|
|
}
|
|
|
|
virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK,
|
|
sizeof(struct virtio_blk_config));
|
|
|
|
s->bs = blk->conf.bs;
|
|
s->conf = &blk->conf;
|
|
memcpy(&(s->blk), blk, sizeof(struct VirtIOBlkConf));
|
|
s->rq = NULL;
|
|
s->sector_mask = (s->conf->logical_block_size / BDRV_SECTOR_SIZE) - 1;
|
|
|
|
s->vq = virtio_add_queue(vdev, 128, virtio_blk_handle_output);
|
|
#ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
|
|
if (!virtio_blk_data_plane_create(vdev, blk, &s->dataplane)) {
|
|
virtio_cleanup(vdev);
|
|
return -1;
|
|
}
|
|
s->migration_state_notifier.notify = virtio_blk_migration_state_changed;
|
|
add_migration_state_change_notifier(&s->migration_state_notifier);
|
|
#endif
|
|
|
|
s->change = qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s);
|
|
register_savevm(qdev, "virtio-blk", virtio_blk_id++, 2,
|
|
virtio_blk_save, virtio_blk_load, s);
|
|
bdrv_set_dev_ops(s->bs, &virtio_block_ops, s);
|
|
bdrv_set_buffer_alignment(s->bs, s->conf->logical_block_size);
|
|
|
|
bdrv_iostatus_enable(s->bs);
|
|
|
|
add_boot_device_path(s->conf->bootindex, qdev, "/disk@0,0");
|
|
return 0;
|
|
}
|
|
|
|
static int virtio_blk_device_exit(DeviceState *dev)
|
|
{
|
|
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
|
|
VirtIOBlock *s = VIRTIO_BLK(dev);
|
|
#ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
|
|
remove_migration_state_change_notifier(&s->migration_state_notifier);
|
|
virtio_blk_data_plane_destroy(s->dataplane);
|
|
s->dataplane = NULL;
|
|
#endif
|
|
qemu_del_vm_change_state_handler(s->change);
|
|
unregister_savevm(dev, "virtio-blk", s);
|
|
blockdev_mark_auto_del(s->bs);
|
|
virtio_cleanup(vdev);
|
|
return 0;
|
|
}
|
|
|
|
static Property virtio_blk_properties[] = {
|
|
DEFINE_VIRTIO_BLK_PROPERTIES(VirtIOBlock, blk),
|
|
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->exit = virtio_blk_device_exit;
|
|
dc->props = virtio_blk_properties;
|
|
set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
|
|
vdc->init = virtio_blk_device_init;
|
|
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;
|
|
}
|
|
|
|
static const TypeInfo virtio_device_info = {
|
|
.name = TYPE_VIRTIO_BLK,
|
|
.parent = TYPE_VIRTIO_DEVICE,
|
|
.instance_size = sizeof(VirtIOBlock),
|
|
.class_init = virtio_blk_class_init,
|
|
};
|
|
|
|
static void virtio_register_types(void)
|
|
{
|
|
type_register_static(&virtio_device_info);
|
|
}
|
|
|
|
type_init(virtio_register_types)
|