virtio-blk: Drop bounce buffer from dataplane code

The block layer will handle the unaligned request.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Fam Zheng 2014-06-11 12:11:44 +08:00 committed by Kevin Wolf
parent 671ec3f056
commit 0bcb34472d

View File

@ -29,8 +29,6 @@ typedef struct {
QEMUIOVector *inhdr; /* iovecs for virtio_blk_inhdr */ QEMUIOVector *inhdr; /* iovecs for virtio_blk_inhdr */
VirtQueueElement *elem; /* saved data from the virtqueue */ VirtQueueElement *elem; /* saved data from the virtqueue */
QEMUIOVector qiov; /* original request iovecs */ QEMUIOVector qiov; /* original request iovecs */
struct iovec bounce_iov; /* used if guest buffers are unaligned */
QEMUIOVector bounce_qiov; /* bounce buffer iovecs */
bool read; /* read or write? */ bool read; /* read or write? */
} VirtIOBlockRequest; } VirtIOBlockRequest;
@ -85,14 +83,6 @@ static void complete_rdwr(void *opaque, int ret)
trace_virtio_blk_data_plane_complete_request(req->s, req->elem->index, ret); trace_virtio_blk_data_plane_complete_request(req->s, req->elem->index, ret);
if (req->read && req->bounce_iov.iov_base) {
qemu_iovec_from_buf(&req->qiov, 0, req->bounce_iov.iov_base, len);
}
if (req->bounce_iov.iov_base) {
qemu_vfree(req->bounce_iov.iov_base);
}
qemu_iovec_from_buf(req->inhdr, 0, &hdr, sizeof(hdr)); qemu_iovec_from_buf(req->inhdr, 0, &hdr, sizeof(hdr));
qemu_iovec_destroy(req->inhdr); qemu_iovec_destroy(req->inhdr);
g_slice_free(QEMUIOVector, req->inhdr); g_slice_free(QEMUIOVector, req->inhdr);
@ -152,21 +142,6 @@ static void do_rdwr_cmd(VirtIOBlockDataPlane *s, bool read,
qiov = &req->qiov; qiov = &req->qiov;
if (!bdrv_qiov_is_aligned(s->blk->conf.bs, qiov)) {
void *bounce_buffer = qemu_blockalign(s->blk->conf.bs, qiov->size);
/* Populate bounce buffer with data for writes */
if (!read) {
qemu_iovec_to_buf(qiov, 0, bounce_buffer, qiov->size);
}
/* Redirect I/O to aligned bounce buffer */
req->bounce_iov.iov_base = bounce_buffer;
req->bounce_iov.iov_len = qiov->size;
qemu_iovec_init_external(&req->bounce_qiov, &req->bounce_iov, 1);
qiov = &req->bounce_qiov;
}
nb_sectors = qiov->size / BDRV_SECTOR_SIZE; nb_sectors = qiov->size / BDRV_SECTOR_SIZE;
if (read) { if (read) {