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/*
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* xen paravirt block device backend
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*
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* (c) Gerd Hoffmann <kraxel@redhat.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; under version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, see <http://www.gnu.org/licenses/>.
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*
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* Contributions after 2012-01-13 are licensed under the terms of the
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* GNU GPL, version 2 or (at your option) any later version.
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*/
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <stdarg.h> |
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#include <string.h> |
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#include <unistd.h> |
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#include <signal.h> |
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#include <inttypes.h> |
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#include <time.h> |
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#include <fcntl.h> |
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#include <errno.h> |
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#include <sys/ioctl.h> |
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#include <sys/types.h> |
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#include <sys/stat.h> |
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#include <sys/mman.h> |
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#include <sys/uio.h> |
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|
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#include "hw.h" |
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#include "xen_backend.h" |
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#include "xen_blkif.h" |
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#include "sysemu/blockdev.h" |
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/* ------------------------------------------------------------- */
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static int batch_maps = 0; |
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static int max_requests = 32; |
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/* ------------------------------------------------------------- */
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#define BLOCK_SIZE 512 |
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#define IOCB_COUNT (BLKIF_MAX_SEGMENTS_PER_REQUEST + 2) |
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|
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struct ioreq {
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blkif_request_t req; |
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int16_t status; |
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/* parsed request */
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off_t start; |
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QEMUIOVector v; |
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int presync;
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int postsync;
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uint8_t mapped; |
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/* grant mapping */
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uint32_t domids[BLKIF_MAX_SEGMENTS_PER_REQUEST]; |
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uint32_t refs[BLKIF_MAX_SEGMENTS_PER_REQUEST]; |
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int prot;
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void *page[BLKIF_MAX_SEGMENTS_PER_REQUEST];
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void *pages;
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|
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/* aio status */
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int aio_inflight;
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int aio_errors;
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|
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struct XenBlkDev *blkdev;
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QLIST_ENTRY(ioreq) list; |
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BlockAcctCookie acct; |
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}; |
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|
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struct XenBlkDev {
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struct XenDevice xendev; /* must be first */ |
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char *params;
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char *mode;
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char *type;
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char *dev;
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char *devtype;
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const char *fileproto; |
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const char *filename; |
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int ring_ref;
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void *sring;
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int64_t file_blk; |
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int64_t file_size; |
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int protocol;
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blkif_back_rings_t rings; |
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int more_work;
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int cnt_map;
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|
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/* request lists */
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QLIST_HEAD(inflight_head, ioreq) inflight; |
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QLIST_HEAD(finished_head, ioreq) finished; |
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QLIST_HEAD(freelist_head, ioreq) freelist; |
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int requests_total;
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int requests_inflight;
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int requests_finished;
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/* qemu block driver */
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DriveInfo *dinfo; |
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BlockDriverState *bs; |
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QEMUBH *bh; |
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}; |
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|
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/* ------------------------------------------------------------- */
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|
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static struct ioreq *ioreq_start(struct XenBlkDev *blkdev) |
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{ |
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struct ioreq *ioreq = NULL; |
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if (QLIST_EMPTY(&blkdev->freelist)) {
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if (blkdev->requests_total >= max_requests) {
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goto out;
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} |
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/* allocate new struct */
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ioreq = g_malloc0(sizeof(*ioreq));
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ioreq->blkdev = blkdev; |
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blkdev->requests_total++; |
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qemu_iovec_init(&ioreq->v, BLKIF_MAX_SEGMENTS_PER_REQUEST); |
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} else {
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/* get one from freelist */
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ioreq = QLIST_FIRST(&blkdev->freelist); |
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QLIST_REMOVE(ioreq, list); |
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qemu_iovec_reset(&ioreq->v); |
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} |
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QLIST_INSERT_HEAD(&blkdev->inflight, ioreq, list); |
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blkdev->requests_inflight++; |
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out:
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return ioreq;
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} |
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static void ioreq_finish(struct ioreq *ioreq) |
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{ |
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struct XenBlkDev *blkdev = ioreq->blkdev;
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QLIST_REMOVE(ioreq, list); |
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QLIST_INSERT_HEAD(&blkdev->finished, ioreq, list); |
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blkdev->requests_inflight--; |
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blkdev->requests_finished++; |
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} |
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static void ioreq_release(struct ioreq *ioreq, bool finish) |
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{ |
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struct XenBlkDev *blkdev = ioreq->blkdev;
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|
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QLIST_REMOVE(ioreq, list); |
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memset(ioreq, 0, sizeof(*ioreq)); |
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ioreq->blkdev = blkdev; |
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QLIST_INSERT_HEAD(&blkdev->freelist, ioreq, list); |
159 |
if (finish) {
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blkdev->requests_finished--; |
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} else {
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blkdev->requests_inflight--; |
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} |
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} |
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/*
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* translate request into iovec + start offset
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* do sanity checks along the way
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*/
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static int ioreq_parse(struct ioreq *ioreq) |
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{ |
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struct XenBlkDev *blkdev = ioreq->blkdev;
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uintptr_t mem; |
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size_t len; |
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int i;
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xen_be_printf(&blkdev->xendev, 3,
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"op %d, nr %d, handle %d, id %" PRId64 ", sector %" PRId64 "\n", |
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ioreq->req.operation, ioreq->req.nr_segments, |
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ioreq->req.handle, ioreq->req.id, ioreq->req.sector_number); |
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switch (ioreq->req.operation) {
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case BLKIF_OP_READ:
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ioreq->prot = PROT_WRITE; /* to memory */
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break;
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case BLKIF_OP_WRITE_BARRIER:
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if (!ioreq->req.nr_segments) {
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ioreq->presync = 1;
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return 0; |
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} |
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ioreq->presync = ioreq->postsync = 1;
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/* fall through */
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case BLKIF_OP_WRITE:
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ioreq->prot = PROT_READ; /* from memory */
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break;
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default:
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xen_be_printf(&blkdev->xendev, 0, "error: unknown operation (%d)\n", |
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ioreq->req.operation); |
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goto err;
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}; |
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if (ioreq->req.operation != BLKIF_OP_READ && blkdev->mode[0] != 'w') { |
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xen_be_printf(&blkdev->xendev, 0, "error: write req for ro device\n"); |
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goto err;
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} |
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ioreq->start = ioreq->req.sector_number * blkdev->file_blk; |
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for (i = 0; i < ioreq->req.nr_segments; i++) { |
208 |
if (i == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
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xen_be_printf(&blkdev->xendev, 0, "error: nr_segments too big\n"); |
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goto err;
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} |
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if (ioreq->req.seg[i].first_sect > ioreq->req.seg[i].last_sect) {
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xen_be_printf(&blkdev->xendev, 0, "error: first > last sector\n"); |
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goto err;
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} |
216 |
if (ioreq->req.seg[i].last_sect * BLOCK_SIZE >= XC_PAGE_SIZE) {
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xen_be_printf(&blkdev->xendev, 0, "error: page crossing\n"); |
218 |
goto err;
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} |
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ioreq->domids[i] = blkdev->xendev.dom; |
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ioreq->refs[i] = ioreq->req.seg[i].gref; |
223 |
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mem = ioreq->req.seg[i].first_sect * blkdev->file_blk; |
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len = (ioreq->req.seg[i].last_sect - ioreq->req.seg[i].first_sect + 1) * blkdev->file_blk;
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qemu_iovec_add(&ioreq->v, (void*)mem, len);
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} |
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if (ioreq->start + ioreq->v.size > blkdev->file_size) {
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xen_be_printf(&blkdev->xendev, 0, "error: access beyond end of file\n"); |
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goto err;
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} |
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return 0; |
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err:
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ioreq->status = BLKIF_RSP_ERROR; |
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return -1; |
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} |
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static void ioreq_unmap(struct ioreq *ioreq) |
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{ |
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XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev; |
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int i;
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if (ioreq->v.niov == 0 || ioreq->mapped == 0) { |
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return;
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} |
247 |
if (batch_maps) {
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if (!ioreq->pages) {
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return;
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} |
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if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->v.niov) != 0) { |
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xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n", |
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strerror(errno)); |
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} |
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ioreq->blkdev->cnt_map -= ioreq->v.niov; |
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ioreq->pages = NULL;
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} else {
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for (i = 0; i < ioreq->v.niov; i++) { |
259 |
if (!ioreq->page[i]) {
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continue;
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} |
262 |
if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0) { |
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xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n", |
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strerror(errno)); |
265 |
} |
266 |
ioreq->blkdev->cnt_map--; |
267 |
ioreq->page[i] = NULL;
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} |
269 |
} |
270 |
ioreq->mapped = 0;
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} |
272 |
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static int ioreq_map(struct ioreq *ioreq) |
274 |
{ |
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XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev; |
276 |
int i;
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277 |
|
278 |
if (ioreq->v.niov == 0 || ioreq->mapped == 1) { |
279 |
return 0; |
280 |
} |
281 |
if (batch_maps) {
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ioreq->pages = xc_gnttab_map_grant_refs |
283 |
(gnt, ioreq->v.niov, ioreq->domids, ioreq->refs, ioreq->prot); |
284 |
if (ioreq->pages == NULL) { |
285 |
xen_be_printf(&ioreq->blkdev->xendev, 0,
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"can't map %d grant refs (%s, %d maps)\n",
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ioreq->v.niov, strerror(errno), ioreq->blkdev->cnt_map); |
288 |
return -1; |
289 |
} |
290 |
for (i = 0; i < ioreq->v.niov; i++) { |
291 |
ioreq->v.iov[i].iov_base = ioreq->pages + i * XC_PAGE_SIZE + |
292 |
(uintptr_t)ioreq->v.iov[i].iov_base; |
293 |
} |
294 |
ioreq->blkdev->cnt_map += ioreq->v.niov; |
295 |
} else {
|
296 |
for (i = 0; i < ioreq->v.niov; i++) { |
297 |
ioreq->page[i] = xc_gnttab_map_grant_ref |
298 |
(gnt, ioreq->domids[i], ioreq->refs[i], ioreq->prot); |
299 |
if (ioreq->page[i] == NULL) { |
300 |
xen_be_printf(&ioreq->blkdev->xendev, 0,
|
301 |
"can't map grant ref %d (%s, %d maps)\n",
|
302 |
ioreq->refs[i], strerror(errno), ioreq->blkdev->cnt_map); |
303 |
ioreq_unmap(ioreq); |
304 |
return -1; |
305 |
} |
306 |
ioreq->v.iov[i].iov_base = ioreq->page[i] + (uintptr_t)ioreq->v.iov[i].iov_base; |
307 |
ioreq->blkdev->cnt_map++; |
308 |
} |
309 |
} |
310 |
ioreq->mapped = 1;
|
311 |
return 0; |
312 |
} |
313 |
|
314 |
static int ioreq_runio_qemu_aio(struct ioreq *ioreq); |
315 |
|
316 |
static void qemu_aio_complete(void *opaque, int ret) |
317 |
{ |
318 |
struct ioreq *ioreq = opaque;
|
319 |
|
320 |
if (ret != 0) { |
321 |
xen_be_printf(&ioreq->blkdev->xendev, 0, "%s I/O error\n", |
322 |
ioreq->req.operation == BLKIF_OP_READ ? "read" : "write"); |
323 |
ioreq->aio_errors++; |
324 |
} |
325 |
|
326 |
ioreq->aio_inflight--; |
327 |
if (ioreq->presync) {
|
328 |
ioreq->presync = 0;
|
329 |
ioreq_runio_qemu_aio(ioreq); |
330 |
return;
|
331 |
} |
332 |
if (ioreq->aio_inflight > 0) { |
333 |
return;
|
334 |
} |
335 |
if (ioreq->postsync) {
|
336 |
ioreq->postsync = 0;
|
337 |
ioreq->aio_inflight++; |
338 |
bdrv_aio_flush(ioreq->blkdev->bs, qemu_aio_complete, ioreq); |
339 |
return;
|
340 |
} |
341 |
|
342 |
ioreq->status = ioreq->aio_errors ? BLKIF_RSP_ERROR : BLKIF_RSP_OKAY; |
343 |
ioreq_unmap(ioreq); |
344 |
ioreq_finish(ioreq); |
345 |
bdrv_acct_done(ioreq->blkdev->bs, &ioreq->acct); |
346 |
qemu_bh_schedule(ioreq->blkdev->bh); |
347 |
} |
348 |
|
349 |
static int ioreq_runio_qemu_aio(struct ioreq *ioreq) |
350 |
{ |
351 |
struct XenBlkDev *blkdev = ioreq->blkdev;
|
352 |
|
353 |
if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1) { |
354 |
goto err_no_map;
|
355 |
} |
356 |
|
357 |
ioreq->aio_inflight++; |
358 |
if (ioreq->presync) {
|
359 |
bdrv_aio_flush(ioreq->blkdev->bs, qemu_aio_complete, ioreq); |
360 |
return 0; |
361 |
} |
362 |
|
363 |
switch (ioreq->req.operation) {
|
364 |
case BLKIF_OP_READ:
|
365 |
bdrv_acct_start(blkdev->bs, &ioreq->acct, ioreq->v.size, BDRV_ACCT_READ); |
366 |
ioreq->aio_inflight++; |
367 |
bdrv_aio_readv(blkdev->bs, ioreq->start / BLOCK_SIZE, |
368 |
&ioreq->v, ioreq->v.size / BLOCK_SIZE, |
369 |
qemu_aio_complete, ioreq); |
370 |
break;
|
371 |
case BLKIF_OP_WRITE:
|
372 |
case BLKIF_OP_WRITE_BARRIER:
|
373 |
if (!ioreq->req.nr_segments) {
|
374 |
break;
|
375 |
} |
376 |
|
377 |
bdrv_acct_start(blkdev->bs, &ioreq->acct, ioreq->v.size, BDRV_ACCT_WRITE); |
378 |
ioreq->aio_inflight++; |
379 |
bdrv_aio_writev(blkdev->bs, ioreq->start / BLOCK_SIZE, |
380 |
&ioreq->v, ioreq->v.size / BLOCK_SIZE, |
381 |
qemu_aio_complete, ioreq); |
382 |
break;
|
383 |
default:
|
384 |
/* unknown operation (shouldn't happen -- parse catches this) */
|
385 |
goto err;
|
386 |
} |
387 |
|
388 |
qemu_aio_complete(ioreq, 0);
|
389 |
|
390 |
return 0; |
391 |
|
392 |
err:
|
393 |
ioreq_unmap(ioreq); |
394 |
err_no_map:
|
395 |
ioreq_finish(ioreq); |
396 |
ioreq->status = BLKIF_RSP_ERROR; |
397 |
return -1; |
398 |
} |
399 |
|
400 |
static int blk_send_response_one(struct ioreq *ioreq) |
401 |
{ |
402 |
struct XenBlkDev *blkdev = ioreq->blkdev;
|
403 |
int send_notify = 0; |
404 |
int have_requests = 0; |
405 |
blkif_response_t resp; |
406 |
void *dst;
|
407 |
|
408 |
resp.id = ioreq->req.id; |
409 |
resp.operation = ioreq->req.operation; |
410 |
resp.status = ioreq->status; |
411 |
|
412 |
/* Place on the response ring for the relevant domain. */
|
413 |
switch (blkdev->protocol) {
|
414 |
case BLKIF_PROTOCOL_NATIVE:
|
415 |
dst = RING_GET_RESPONSE(&blkdev->rings.native, blkdev->rings.native.rsp_prod_pvt); |
416 |
break;
|
417 |
case BLKIF_PROTOCOL_X86_32:
|
418 |
dst = RING_GET_RESPONSE(&blkdev->rings.x86_32_part, |
419 |
blkdev->rings.x86_32_part.rsp_prod_pvt); |
420 |
break;
|
421 |
case BLKIF_PROTOCOL_X86_64:
|
422 |
dst = RING_GET_RESPONSE(&blkdev->rings.x86_64_part, |
423 |
blkdev->rings.x86_64_part.rsp_prod_pvt); |
424 |
break;
|
425 |
default:
|
426 |
dst = NULL;
|
427 |
} |
428 |
memcpy(dst, &resp, sizeof(resp));
|
429 |
blkdev->rings.common.rsp_prod_pvt++; |
430 |
|
431 |
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&blkdev->rings.common, send_notify); |
432 |
if (blkdev->rings.common.rsp_prod_pvt == blkdev->rings.common.req_cons) {
|
433 |
/*
|
434 |
* Tail check for pending requests. Allows frontend to avoid
|
435 |
* notifications if requests are already in flight (lower
|
436 |
* overheads and promotes batching).
|
437 |
*/
|
438 |
RING_FINAL_CHECK_FOR_REQUESTS(&blkdev->rings.common, have_requests); |
439 |
} else if (RING_HAS_UNCONSUMED_REQUESTS(&blkdev->rings.common)) { |
440 |
have_requests = 1;
|
441 |
} |
442 |
|
443 |
if (have_requests) {
|
444 |
blkdev->more_work++; |
445 |
} |
446 |
return send_notify;
|
447 |
} |
448 |
|
449 |
/* walk finished list, send outstanding responses, free requests */
|
450 |
static void blk_send_response_all(struct XenBlkDev *blkdev) |
451 |
{ |
452 |
struct ioreq *ioreq;
|
453 |
int send_notify = 0; |
454 |
|
455 |
while (!QLIST_EMPTY(&blkdev->finished)) {
|
456 |
ioreq = QLIST_FIRST(&blkdev->finished); |
457 |
send_notify += blk_send_response_one(ioreq); |
458 |
ioreq_release(ioreq, true);
|
459 |
} |
460 |
if (send_notify) {
|
461 |
xen_be_send_notify(&blkdev->xendev); |
462 |
} |
463 |
} |
464 |
|
465 |
static int blk_get_request(struct XenBlkDev *blkdev, struct ioreq *ioreq, RING_IDX rc) |
466 |
{ |
467 |
switch (blkdev->protocol) {
|
468 |
case BLKIF_PROTOCOL_NATIVE:
|
469 |
memcpy(&ioreq->req, RING_GET_REQUEST(&blkdev->rings.native, rc), |
470 |
sizeof(ioreq->req));
|
471 |
break;
|
472 |
case BLKIF_PROTOCOL_X86_32:
|
473 |
blkif_get_x86_32_req(&ioreq->req, |
474 |
RING_GET_REQUEST(&blkdev->rings.x86_32_part, rc)); |
475 |
break;
|
476 |
case BLKIF_PROTOCOL_X86_64:
|
477 |
blkif_get_x86_64_req(&ioreq->req, |
478 |
RING_GET_REQUEST(&blkdev->rings.x86_64_part, rc)); |
479 |
break;
|
480 |
} |
481 |
return 0; |
482 |
} |
483 |
|
484 |
static void blk_handle_requests(struct XenBlkDev *blkdev) |
485 |
{ |
486 |
RING_IDX rc, rp; |
487 |
struct ioreq *ioreq;
|
488 |
|
489 |
blkdev->more_work = 0;
|
490 |
|
491 |
rc = blkdev->rings.common.req_cons; |
492 |
rp = blkdev->rings.common.sring->req_prod; |
493 |
xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
|
494 |
|
495 |
blk_send_response_all(blkdev); |
496 |
while (rc != rp) {
|
497 |
/* pull request from ring */
|
498 |
if (RING_REQUEST_CONS_OVERFLOW(&blkdev->rings.common, rc)) {
|
499 |
break;
|
500 |
} |
501 |
ioreq = ioreq_start(blkdev); |
502 |
if (ioreq == NULL) { |
503 |
blkdev->more_work++; |
504 |
break;
|
505 |
} |
506 |
blk_get_request(blkdev, ioreq, rc); |
507 |
blkdev->rings.common.req_cons = ++rc; |
508 |
|
509 |
/* parse them */
|
510 |
if (ioreq_parse(ioreq) != 0) { |
511 |
if (blk_send_response_one(ioreq)) {
|
512 |
xen_be_send_notify(&blkdev->xendev); |
513 |
} |
514 |
ioreq_release(ioreq, false);
|
515 |
continue;
|
516 |
} |
517 |
|
518 |
ioreq_runio_qemu_aio(ioreq); |
519 |
} |
520 |
|
521 |
if (blkdev->more_work && blkdev->requests_inflight < max_requests) {
|
522 |
qemu_bh_schedule(blkdev->bh); |
523 |
} |
524 |
} |
525 |
|
526 |
/* ------------------------------------------------------------- */
|
527 |
|
528 |
static void blk_bh(void *opaque) |
529 |
{ |
530 |
struct XenBlkDev *blkdev = opaque;
|
531 |
blk_handle_requests(blkdev); |
532 |
} |
533 |
|
534 |
/*
|
535 |
* We need to account for the grant allocations requiring contiguous
|
536 |
* chunks; the worst case number would be
|
537 |
* max_req * max_seg + (max_req - 1) * (max_seg - 1) + 1,
|
538 |
* but in order to keep things simple just use
|
539 |
* 2 * max_req * max_seg.
|
540 |
*/
|
541 |
#define MAX_GRANTS(max_req, max_seg) (2 * (max_req) * (max_seg)) |
542 |
|
543 |
static void blk_alloc(struct XenDevice *xendev) |
544 |
{ |
545 |
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); |
546 |
|
547 |
QLIST_INIT(&blkdev->inflight); |
548 |
QLIST_INIT(&blkdev->finished); |
549 |
QLIST_INIT(&blkdev->freelist); |
550 |
blkdev->bh = qemu_bh_new(blk_bh, blkdev); |
551 |
if (xen_mode != XEN_EMULATE) {
|
552 |
batch_maps = 1;
|
553 |
} |
554 |
if (xc_gnttab_set_max_grants(xendev->gnttabdev,
|
555 |
MAX_GRANTS(max_requests, BLKIF_MAX_SEGMENTS_PER_REQUEST)) < 0) {
|
556 |
xen_be_printf(xendev, 0, "xc_gnttab_set_max_grants failed: %s\n", |
557 |
strerror(errno)); |
558 |
} |
559 |
} |
560 |
|
561 |
static int blk_init(struct XenDevice *xendev) |
562 |
{ |
563 |
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); |
564 |
int index, qflags, info = 0; |
565 |
|
566 |
/* read xenstore entries */
|
567 |
if (blkdev->params == NULL) { |
568 |
char *h = NULL; |
569 |
blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params");
|
570 |
if (blkdev->params != NULL) { |
571 |
h = strchr(blkdev->params, ':');
|
572 |
} |
573 |
if (h != NULL) { |
574 |
blkdev->fileproto = blkdev->params; |
575 |
blkdev->filename = h+1;
|
576 |
*h = 0;
|
577 |
} else {
|
578 |
blkdev->fileproto = "<unset>";
|
579 |
blkdev->filename = blkdev->params; |
580 |
} |
581 |
} |
582 |
if (!strcmp("aio", blkdev->fileproto)) { |
583 |
blkdev->fileproto = "raw";
|
584 |
} |
585 |
if (blkdev->mode == NULL) { |
586 |
blkdev->mode = xenstore_read_be_str(&blkdev->xendev, "mode");
|
587 |
} |
588 |
if (blkdev->type == NULL) { |
589 |
blkdev->type = xenstore_read_be_str(&blkdev->xendev, "type");
|
590 |
} |
591 |
if (blkdev->dev == NULL) { |
592 |
blkdev->dev = xenstore_read_be_str(&blkdev->xendev, "dev");
|
593 |
} |
594 |
if (blkdev->devtype == NULL) { |
595 |
blkdev->devtype = xenstore_read_be_str(&blkdev->xendev, "device-type");
|
596 |
} |
597 |
|
598 |
/* do we have all we need? */
|
599 |
if (blkdev->params == NULL || |
600 |
blkdev->mode == NULL ||
|
601 |
blkdev->type == NULL ||
|
602 |
blkdev->dev == NULL) {
|
603 |
goto out_error;
|
604 |
} |
605 |
|
606 |
/* read-only ? */
|
607 |
qflags = BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NATIVE_AIO; |
608 |
if (strcmp(blkdev->mode, "w") == 0) { |
609 |
qflags |= BDRV_O_RDWR; |
610 |
} else {
|
611 |
info |= VDISK_READONLY; |
612 |
} |
613 |
|
614 |
/* cdrom ? */
|
615 |
if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom")) { |
616 |
info |= VDISK_CDROM; |
617 |
} |
618 |
|
619 |
/* init qemu block driver */
|
620 |
index = (blkdev->xendev.dev - 202 * 256) / 16; |
621 |
blkdev->dinfo = drive_get(IF_XEN, 0, index);
|
622 |
if (!blkdev->dinfo) {
|
623 |
/* setup via xenbus -> create new block driver instance */
|
624 |
xen_be_printf(&blkdev->xendev, 2, "create new bdrv (xenbus setup)\n"); |
625 |
blkdev->bs = bdrv_new(blkdev->dev); |
626 |
if (blkdev->bs) {
|
627 |
if (bdrv_open(blkdev->bs, blkdev->filename, qflags,
|
628 |
bdrv_find_whitelisted_format(blkdev->fileproto)) != 0) {
|
629 |
bdrv_delete(blkdev->bs); |
630 |
blkdev->bs = NULL;
|
631 |
} |
632 |
} |
633 |
if (!blkdev->bs) {
|
634 |
goto out_error;
|
635 |
} |
636 |
} else {
|
637 |
/* setup via qemu cmdline -> already setup for us */
|
638 |
xen_be_printf(&blkdev->xendev, 2, "get configured bdrv (cmdline setup)\n"); |
639 |
blkdev->bs = blkdev->dinfo->bdrv; |
640 |
} |
641 |
bdrv_attach_dev_nofail(blkdev->bs, blkdev); |
642 |
blkdev->file_blk = BLOCK_SIZE; |
643 |
blkdev->file_size = bdrv_getlength(blkdev->bs); |
644 |
if (blkdev->file_size < 0) { |
645 |
xen_be_printf(&blkdev->xendev, 1, "bdrv_getlength: %d (%s) | drv %s\n", |
646 |
(int)blkdev->file_size, strerror(-blkdev->file_size),
|
647 |
bdrv_get_format_name(blkdev->bs) ?: "-");
|
648 |
blkdev->file_size = 0;
|
649 |
} |
650 |
|
651 |
xen_be_printf(xendev, 1, "type \"%s\", fileproto \"%s\", filename \"%s\"," |
652 |
" size %" PRId64 " (%" PRId64 " MB)\n", |
653 |
blkdev->type, blkdev->fileproto, blkdev->filename, |
654 |
blkdev->file_size, blkdev->file_size >> 20);
|
655 |
|
656 |
/* fill info */
|
657 |
xenstore_write_be_int(&blkdev->xendev, "feature-barrier", 1); |
658 |
xenstore_write_be_int(&blkdev->xendev, "info", info);
|
659 |
xenstore_write_be_int(&blkdev->xendev, "sector-size", blkdev->file_blk);
|
660 |
xenstore_write_be_int(&blkdev->xendev, "sectors",
|
661 |
blkdev->file_size / blkdev->file_blk); |
662 |
return 0; |
663 |
|
664 |
out_error:
|
665 |
g_free(blkdev->params); |
666 |
blkdev->params = NULL;
|
667 |
g_free(blkdev->mode); |
668 |
blkdev->mode = NULL;
|
669 |
g_free(blkdev->type); |
670 |
blkdev->type = NULL;
|
671 |
g_free(blkdev->dev); |
672 |
blkdev->dev = NULL;
|
673 |
g_free(blkdev->devtype); |
674 |
blkdev->devtype = NULL;
|
675 |
return -1; |
676 |
} |
677 |
|
678 |
static int blk_connect(struct XenDevice *xendev) |
679 |
{ |
680 |
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); |
681 |
|
682 |
if (xenstore_read_fe_int(&blkdev->xendev, "ring-ref", &blkdev->ring_ref) == -1) { |
683 |
return -1; |
684 |
} |
685 |
if (xenstore_read_fe_int(&blkdev->xendev, "event-channel", |
686 |
&blkdev->xendev.remote_port) == -1) {
|
687 |
return -1; |
688 |
} |
689 |
|
690 |
blkdev->protocol = BLKIF_PROTOCOL_NATIVE; |
691 |
if (blkdev->xendev.protocol) {
|
692 |
if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_32) == 0) { |
693 |
blkdev->protocol = BLKIF_PROTOCOL_X86_32; |
694 |
} |
695 |
if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_64) == 0) { |
696 |
blkdev->protocol = BLKIF_PROTOCOL_X86_64; |
697 |
} |
698 |
} |
699 |
|
700 |
blkdev->sring = xc_gnttab_map_grant_ref(blkdev->xendev.gnttabdev, |
701 |
blkdev->xendev.dom, |
702 |
blkdev->ring_ref, |
703 |
PROT_READ | PROT_WRITE); |
704 |
if (!blkdev->sring) {
|
705 |
return -1; |
706 |
} |
707 |
blkdev->cnt_map++; |
708 |
|
709 |
switch (blkdev->protocol) {
|
710 |
case BLKIF_PROTOCOL_NATIVE:
|
711 |
{ |
712 |
blkif_sring_t *sring_native = blkdev->sring; |
713 |
BACK_RING_INIT(&blkdev->rings.native, sring_native, XC_PAGE_SIZE); |
714 |
break;
|
715 |
} |
716 |
case BLKIF_PROTOCOL_X86_32:
|
717 |
{ |
718 |
blkif_x86_32_sring_t *sring_x86_32 = blkdev->sring; |
719 |
|
720 |
BACK_RING_INIT(&blkdev->rings.x86_32_part, sring_x86_32, XC_PAGE_SIZE); |
721 |
break;
|
722 |
} |
723 |
case BLKIF_PROTOCOL_X86_64:
|
724 |
{ |
725 |
blkif_x86_64_sring_t *sring_x86_64 = blkdev->sring; |
726 |
|
727 |
BACK_RING_INIT(&blkdev->rings.x86_64_part, sring_x86_64, XC_PAGE_SIZE); |
728 |
break;
|
729 |
} |
730 |
} |
731 |
|
732 |
xen_be_bind_evtchn(&blkdev->xendev); |
733 |
|
734 |
xen_be_printf(&blkdev->xendev, 1, "ok: proto %s, ring-ref %d, " |
735 |
"remote port %d, local port %d\n",
|
736 |
blkdev->xendev.protocol, blkdev->ring_ref, |
737 |
blkdev->xendev.remote_port, blkdev->xendev.local_port); |
738 |
return 0; |
739 |
} |
740 |
|
741 |
static void blk_disconnect(struct XenDevice *xendev) |
742 |
{ |
743 |
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); |
744 |
|
745 |
if (blkdev->bs) {
|
746 |
if (!blkdev->dinfo) {
|
747 |
/* close/delete only if we created it ourself */
|
748 |
bdrv_close(blkdev->bs); |
749 |
bdrv_detach_dev(blkdev->bs, blkdev); |
750 |
bdrv_delete(blkdev->bs); |
751 |
} |
752 |
blkdev->bs = NULL;
|
753 |
} |
754 |
xen_be_unbind_evtchn(&blkdev->xendev); |
755 |
|
756 |
if (blkdev->sring) {
|
757 |
xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
|
758 |
blkdev->cnt_map--; |
759 |
blkdev->sring = NULL;
|
760 |
} |
761 |
} |
762 |
|
763 |
static int blk_free(struct XenDevice *xendev) |
764 |
{ |
765 |
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); |
766 |
struct ioreq *ioreq;
|
767 |
|
768 |
if (blkdev->bs || blkdev->sring) {
|
769 |
blk_disconnect(xendev); |
770 |
} |
771 |
|
772 |
while (!QLIST_EMPTY(&blkdev->freelist)) {
|
773 |
ioreq = QLIST_FIRST(&blkdev->freelist); |
774 |
QLIST_REMOVE(ioreq, list); |
775 |
qemu_iovec_destroy(&ioreq->v); |
776 |
g_free(ioreq); |
777 |
} |
778 |
|
779 |
g_free(blkdev->params); |
780 |
g_free(blkdev->mode); |
781 |
g_free(blkdev->type); |
782 |
g_free(blkdev->dev); |
783 |
g_free(blkdev->devtype); |
784 |
qemu_bh_delete(blkdev->bh); |
785 |
return 0; |
786 |
} |
787 |
|
788 |
static void blk_event(struct XenDevice *xendev) |
789 |
{ |
790 |
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); |
791 |
|
792 |
qemu_bh_schedule(blkdev->bh); |
793 |
} |
794 |
|
795 |
struct XenDevOps xen_blkdev_ops = {
|
796 |
.size = sizeof(struct XenBlkDev), |
797 |
.flags = DEVOPS_FLAG_NEED_GNTDEV, |
798 |
.alloc = blk_alloc, |
799 |
.init = blk_init, |
800 |
.initialise = blk_connect, |
801 |
.disconnect = blk_disconnect, |
802 |
.event = blk_event, |
803 |
.free = blk_free, |
804 |
}; |