Example #1
0
static void blk_handle_requests(struct XenBlkDev *blkdev)
{
    RING_IDX rc, rp;
    struct ioreq *ioreq;

    blkdev->more_work = 0;

    rc = blkdev->rings.common.req_cons;
    rp = blkdev->rings.common.sring->req_prod;
    xen_rmb(); /* Ensure we see queued requests up to 'rp'. */

    if (use_aio) {
        blk_send_response_all(blkdev);
    }
    while (rc != rp) {
        /* pull request from ring */
        if (RING_REQUEST_CONS_OVERFLOW(&blkdev->rings.common, rc)) {
            break;
        }
        ioreq = ioreq_start(blkdev);
        if (ioreq == NULL) {
            blkdev->more_work++;
            break;
        }
        blk_get_request(blkdev, ioreq, rc);
        blkdev->rings.common.req_cons = ++rc;

        /* parse them */
        if (ioreq_parse(ioreq) != 0) {
            if (blk_send_response_one(ioreq)) {
                xen_be_send_notify(&blkdev->xendev);
            }
            ioreq_release(ioreq);
            continue;
        }

        if (use_aio) {
            /* run i/o in aio mode */
            ioreq_runio_qemu_aio(ioreq);
        } else {
            /* run i/o in sync mode */
            ioreq_runio_qemu_sync(ioreq);
        }
    }
    if (!use_aio) {
        blk_send_response_all(blkdev);
    }

    if (blkdev->more_work && blkdev->requests_inflight < max_requests) {
        qemu_bh_schedule(blkdev->bh);
    }
}
Example #2
0
static void blk_handle_requests(struct XenBlkDev *blkdev)
{
    RING_IDX rc, rp;
    struct ioreq *ioreq;

    blkdev->more_work = 0;

    rc = blkdev->rings.common.req_cons;
    rp = blkdev->rings.common.sring->req_prod;
    xen_rmb(); /* Ensure we see queued requests up to 'rp'. */

    blk_send_response_all(blkdev);
    while (rc != rp) {
        /* pull request from ring */
        if (RING_REQUEST_CONS_OVERFLOW(&blkdev->rings.common, rc)) {
            break;
        }
        ioreq = ioreq_start(blkdev);
        if (ioreq == NULL) {
            blkdev->more_work++;
            break;
        }
        blk_get_request(blkdev, ioreq, rc);
        blkdev->rings.common.req_cons = ++rc;

        /* parse them */
        if (ioreq_parse(ioreq) != 0) {

            switch (ioreq->req.operation) {
            case BLKIF_OP_READ:
                block_acct_invalid(blk_get_stats(blkdev->blk),
                                   BLOCK_ACCT_READ);
                break;
            case BLKIF_OP_WRITE:
                block_acct_invalid(blk_get_stats(blkdev->blk),
                                   BLOCK_ACCT_WRITE);
                break;
            case BLKIF_OP_FLUSH_DISKCACHE:
                block_acct_invalid(blk_get_stats(blkdev->blk),
                                   BLOCK_ACCT_FLUSH);
            default:
                break;
            };

            if (blk_send_response_one(ioreq)) {
                xen_pv_send_notify(&blkdev->xendev);
            }
            ioreq_release(ioreq, false);
            continue;
        }

        ioreq_runio_qemu_aio(ioreq);
    }

    if (blkdev->more_work && blkdev->requests_inflight < blkdev->max_requests) {
        qemu_bh_schedule(blkdev->bh);
    }
}