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d5b93ddfef
qemu/hw/xen_disk.c
Anthony PERARD d5b93ddfef xen: Support new libxc calls from xen unstable. 
This patch updates the libxenctrl calls in Qemu to use the new interface,
otherwise Qemu wouldn't be able to build against new versions of the
library.

We check libxenctrl version in configure, from Xen 3.3.0 to Xen
unstable.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-05-08 10:09:59 +02:00

833 lines
25 KiB
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/*
* xen paravirt block device backend
*
* (c) Gerd Hoffmann <kraxel@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; under version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <inttypes.h>
#include <time.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/uio.h>
#include <xs.h>
#include <xenctrl.h>
#include <xen/io/xenbus.h>
#include "hw.h"
#include "block_int.h"
#include "qemu-char.h"
#include "xen_blkif.h"
#include "xen_backend.h"
#include "blockdev.h"
/* ------------------------------------------------------------- */
static int syncwrite = 0;
static int batch_maps = 0;
static int max_requests = 32;
static int use_aio = 1;
/* ------------------------------------------------------------- */
#define BLOCK_SIZE 512
#define IOCB_COUNT (BLKIF_MAX_SEGMENTS_PER_REQUEST + 2)
struct ioreq {
blkif_request_t req;
int16_t status;
/* parsed request */
off_t start;
QEMUIOVector v;
int presync;
int postsync;
/* grant mapping */
uint32_t domids[BLKIF_MAX_SEGMENTS_PER_REQUEST];
uint32_t refs[BLKIF_MAX_SEGMENTS_PER_REQUEST];
int prot;
void *page[BLKIF_MAX_SEGMENTS_PER_REQUEST];
void *pages;
/* aio status */
int aio_inflight;
int aio_errors;
struct XenBlkDev *blkdev;
QLIST_ENTRY(ioreq) list;
};
struct XenBlkDev {
struct XenDevice xendev; /* must be first */
char *params;
char *mode;
char *type;
char *dev;
char *devtype;
const char *fileproto;
const char *filename;
int ring_ref;
void *sring;
int64_t file_blk;
int64_t file_size;
int protocol;
blkif_back_rings_t rings;
int more_work;
int cnt_map;
/* request lists */
QLIST_HEAD(inflight_head, ioreq) inflight;
QLIST_HEAD(finished_head, ioreq) finished;
QLIST_HEAD(freelist_head, ioreq) freelist;
int requests_total;
int requests_inflight;
int requests_finished;
/* qemu block driver */
DriveInfo *dinfo;
BlockDriverState *bs;
QEMUBH *bh;
};
/* ------------------------------------------------------------- */
static struct ioreq *ioreq_start(struct XenBlkDev *blkdev)
{
struct ioreq *ioreq = NULL;
if (QLIST_EMPTY(&blkdev->freelist)) {
if (blkdev->requests_total >= max_requests) {
goto out;
}
/* allocate new struct */
ioreq = qemu_mallocz(sizeof(*ioreq));
ioreq->blkdev = blkdev;
blkdev->requests_total++;
qemu_iovec_init(&ioreq->v, BLKIF_MAX_SEGMENTS_PER_REQUEST);
} else {
/* get one from freelist */
ioreq = QLIST_FIRST(&blkdev->freelist);
QLIST_REMOVE(ioreq, list);
qemu_iovec_reset(&ioreq->v);
}
QLIST_INSERT_HEAD(&blkdev->inflight, ioreq, list);
blkdev->requests_inflight++;
out:
return ioreq;
}
static void ioreq_finish(struct ioreq *ioreq)
{
struct XenBlkDev *blkdev = ioreq->blkdev;
QLIST_REMOVE(ioreq, list);
QLIST_INSERT_HEAD(&blkdev->finished, ioreq, list);
blkdev->requests_inflight--;
blkdev->requests_finished++;
}
static void ioreq_release(struct ioreq *ioreq)
{
struct XenBlkDev *blkdev = ioreq->blkdev;
QLIST_REMOVE(ioreq, list);
memset(ioreq, 0, sizeof(*ioreq));
ioreq->blkdev = blkdev;
QLIST_INSERT_HEAD(&blkdev->freelist, ioreq, list);
blkdev->requests_finished--;
}
/*
* translate request into iovec + start offset
* do sanity checks along the way
*/
static int ioreq_parse(struct ioreq *ioreq)
{
struct XenBlkDev *blkdev = ioreq->blkdev;
uintptr_t mem;
size_t len;
int i;
xen_be_printf(&blkdev->xendev, 3,
"op %d, nr %d, handle %d, id %" PRId64 ", sector %" PRId64 "\n",
ioreq->req.operation, ioreq->req.nr_segments,
ioreq->req.handle, ioreq->req.id, ioreq->req.sector_number);
switch (ioreq->req.operation) {
case BLKIF_OP_READ:
ioreq->prot = PROT_WRITE; /* to memory */
break;
case BLKIF_OP_WRITE_BARRIER:
if (!ioreq->req.nr_segments) {
ioreq->presync = 1;
return 0;
}
if (!syncwrite) {
ioreq->presync = ioreq->postsync = 1;
}
/* fall through */
case BLKIF_OP_WRITE:
ioreq->prot = PROT_READ; /* from memory */
if (syncwrite) {
ioreq->postsync = 1;
}
break;
default:
xen_be_printf(&blkdev->xendev, 0, "error: unknown operation (%d)\n",
ioreq->req.operation);
goto err;
};
if (ioreq->req.operation != BLKIF_OP_READ && blkdev->mode[0] != 'w') {
xen_be_printf(&blkdev->xendev, 0, "error: write req for ro device\n");
goto err;
}
ioreq->start = ioreq->req.sector_number * blkdev->file_blk;
for (i = 0; i < ioreq->req.nr_segments; i++) {
if (i == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
xen_be_printf(&blkdev->xendev, 0, "error: nr_segments too big\n");
goto err;
}
if (ioreq->req.seg[i].first_sect > ioreq->req.seg[i].last_sect) {
xen_be_printf(&blkdev->xendev, 0, "error: first > last sector\n");
goto err;
}
if (ioreq->req.seg[i].last_sect * BLOCK_SIZE >= XC_PAGE_SIZE) {
xen_be_printf(&blkdev->xendev, 0, "error: page crossing\n");
goto err;
}
ioreq->domids[i] = blkdev->xendev.dom;
ioreq->refs[i] = ioreq->req.seg[i].gref;
mem = ioreq->req.seg[i].first_sect * blkdev->file_blk;
len = (ioreq->req.seg[i].last_sect - ioreq->req.seg[i].first_sect + 1) * blkdev->file_blk;
qemu_iovec_add(&ioreq->v, (void*)mem, len);
}
if (ioreq->start + ioreq->v.size > blkdev->file_size) {
xen_be_printf(&blkdev->xendev, 0, "error: access beyond end of file\n");
goto err;
}
return 0;
err:
ioreq->status = BLKIF_RSP_ERROR;
return -1;
}
static void ioreq_unmap(struct ioreq *ioreq)
{
XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
int i;
if (ioreq->v.niov == 0) {
return;
}
if (batch_maps) {
if (!ioreq->pages) {
return;
}
if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->v.niov) != 0) {
xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
strerror(errno));
}
ioreq->blkdev->cnt_map -= ioreq->v.niov;
ioreq->pages = NULL;
} else {
for (i = 0; i < ioreq->v.niov; i++) {
if (!ioreq->page[i]) {
continue;
}
if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0) {
xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
strerror(errno));
}
ioreq->blkdev->cnt_map--;
ioreq->page[i] = NULL;
}
}
}
static int ioreq_map(struct ioreq *ioreq)
{
XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
int i;
if (ioreq->v.niov == 0) {
return 0;
}
if (batch_maps) {
ioreq->pages = xc_gnttab_map_grant_refs
(gnt, ioreq->v.niov, ioreq->domids, ioreq->refs, ioreq->prot);
if (ioreq->pages == NULL) {
xen_be_printf(&ioreq->blkdev->xendev, 0,
"can't map %d grant refs (%s, %d maps)\n",
ioreq->v.niov, strerror(errno), ioreq->blkdev->cnt_map);
return -1;
}
for (i = 0; i < ioreq->v.niov; i++) {
ioreq->v.iov[i].iov_base = ioreq->pages + i * XC_PAGE_SIZE +
(uintptr_t)ioreq->v.iov[i].iov_base;
}
ioreq->blkdev->cnt_map += ioreq->v.niov;
} else {
for (i = 0; i < ioreq->v.niov; i++) {
ioreq->page[i] = xc_gnttab_map_grant_ref
(gnt, ioreq->domids[i], ioreq->refs[i], ioreq->prot);
if (ioreq->page[i] == NULL) {
xen_be_printf(&ioreq->blkdev->xendev, 0,
"can't map grant ref %d (%s, %d maps)\n",
ioreq->refs[i], strerror(errno), ioreq->blkdev->cnt_map);
ioreq_unmap(ioreq);
return -1;
}
ioreq->v.iov[i].iov_base = ioreq->page[i] + (uintptr_t)ioreq->v.iov[i].iov_base;
ioreq->blkdev->cnt_map++;
}
}
return 0;
}
static int ioreq_runio_qemu_sync(struct ioreq *ioreq)
{
struct XenBlkDev *blkdev = ioreq->blkdev;
int i, rc, len = 0;
off_t pos;
if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1) {
goto err_no_map;
}
if (ioreq->presync) {
bdrv_flush(blkdev->bs);
}
switch (ioreq->req.operation) {
case BLKIF_OP_READ:
pos = ioreq->start;
for (i = 0; i < ioreq->v.niov; i++) {
rc = bdrv_read(blkdev->bs, pos / BLOCK_SIZE,
ioreq->v.iov[i].iov_base,
ioreq->v.iov[i].iov_len / BLOCK_SIZE);
if (rc != 0) {
xen_be_printf(&blkdev->xendev, 0, "rd I/O error (%p, len %zd)\n",
ioreq->v.iov[i].iov_base,
ioreq->v.iov[i].iov_len);
goto err;
}
len += ioreq->v.iov[i].iov_len;
pos += ioreq->v.iov[i].iov_len;
}
break;
case BLKIF_OP_WRITE:
case BLKIF_OP_WRITE_BARRIER:
if (!ioreq->req.nr_segments) {
break;
}
pos = ioreq->start;
for (i = 0; i < ioreq->v.niov; i++) {
rc = bdrv_write(blkdev->bs, pos / BLOCK_SIZE,
ioreq->v.iov[i].iov_base,
ioreq->v.iov[i].iov_len / BLOCK_SIZE);
if (rc != 0) {
xen_be_printf(&blkdev->xendev, 0, "wr I/O error (%p, len %zd)\n",
ioreq->v.iov[i].iov_base,
ioreq->v.iov[i].iov_len);
goto err;
}
len += ioreq->v.iov[i].iov_len;
pos += ioreq->v.iov[i].iov_len;
}
break;
default:
/* unknown operation (shouldn't happen -- parse catches this) */
goto err;
}
if (ioreq->postsync) {
bdrv_flush(blkdev->bs);
}
ioreq->status = BLKIF_RSP_OKAY;
ioreq_unmap(ioreq);
ioreq_finish(ioreq);
return 0;
err:
ioreq_unmap(ioreq);
err_no_map:
ioreq_finish(ioreq);
ioreq->status = BLKIF_RSP_ERROR;
return -1;
}
static void qemu_aio_complete(void *opaque, int ret)
{
struct ioreq *ioreq = opaque;
if (ret != 0) {
xen_be_printf(&ioreq->blkdev->xendev, 0, "%s I/O error\n",
ioreq->req.operation == BLKIF_OP_READ ? "read" : "write");
ioreq->aio_errors++;
}
ioreq->aio_inflight--;
if (ioreq->aio_inflight > 0) {
return;
}
ioreq->status = ioreq->aio_errors ? BLKIF_RSP_ERROR : BLKIF_RSP_OKAY;
ioreq_unmap(ioreq);
ioreq_finish(ioreq);
qemu_bh_schedule(ioreq->blkdev->bh);
}
static int ioreq_runio_qemu_aio(struct ioreq *ioreq)
{
struct XenBlkDev *blkdev = ioreq->blkdev;
if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1) {
goto err_no_map;
}
ioreq->aio_inflight++;
if (ioreq->presync) {
bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
}
switch (ioreq->req.operation) {
case BLKIF_OP_READ:
ioreq->aio_inflight++;
bdrv_aio_readv(blkdev->bs, ioreq->start / BLOCK_SIZE,
&ioreq->v, ioreq->v.size / BLOCK_SIZE,
qemu_aio_complete, ioreq);
break;
case BLKIF_OP_WRITE:
case BLKIF_OP_WRITE_BARRIER:
if (!ioreq->req.nr_segments) {
break;
}
ioreq->aio_inflight++;
bdrv_aio_writev(blkdev->bs, ioreq->start / BLOCK_SIZE,
&ioreq->v, ioreq->v.size / BLOCK_SIZE,
qemu_aio_complete, ioreq);
break;
default:
/* unknown operation (shouldn't happen -- parse catches this) */
goto err;
}
if (ioreq->postsync) {
bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
}
qemu_aio_complete(ioreq, 0);
return 0;
err:
ioreq_unmap(ioreq);
err_no_map:
ioreq_finish(ioreq);
ioreq->status = BLKIF_RSP_ERROR;
return -1;
}
static int blk_send_response_one(struct ioreq *ioreq)
{
struct XenBlkDev *blkdev = ioreq->blkdev;
int send_notify = 0;
int have_requests = 0;
blkif_response_t resp;
void *dst;
resp.id = ioreq->req.id;
resp.operation = ioreq->req.operation;
resp.status = ioreq->status;
/* Place on the response ring for the relevant domain. */
switch (blkdev->protocol) {
case BLKIF_PROTOCOL_NATIVE:
dst = RING_GET_RESPONSE(&blkdev->rings.native, blkdev->rings.native.rsp_prod_pvt);
break;
case BLKIF_PROTOCOL_X86_32:
dst = RING_GET_RESPONSE(&blkdev->rings.x86_32_part,
blkdev->rings.x86_32_part.rsp_prod_pvt);
break;
case BLKIF_PROTOCOL_X86_64:
dst = RING_GET_RESPONSE(&blkdev->rings.x86_64_part,
blkdev->rings.x86_64_part.rsp_prod_pvt);
break;
default:
dst = NULL;
}
memcpy(dst, &resp, sizeof(resp));
blkdev->rings.common.rsp_prod_pvt++;
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&blkdev->rings.common, send_notify);
if (blkdev->rings.common.rsp_prod_pvt == blkdev->rings.common.req_cons) {
/*
* Tail check for pending requests. Allows frontend to avoid
* notifications if requests are already in flight (lower
* overheads and promotes batching).
*/
RING_FINAL_CHECK_FOR_REQUESTS(&blkdev->rings.common, have_requests);
} else if (RING_HAS_UNCONSUMED_REQUESTS(&blkdev->rings.common)) {
have_requests = 1;
}
if (have_requests) {
blkdev->more_work++;
}
return send_notify;
}
/* walk finished list, send outstanding responses, free requests */
static void blk_send_response_all(struct XenBlkDev *blkdev)
{
struct ioreq *ioreq;
int send_notify = 0;
while (!QLIST_EMPTY(&blkdev->finished)) {
ioreq = QLIST_FIRST(&blkdev->finished);
send_notify += blk_send_response_one(ioreq);
ioreq_release(ioreq);
}
if (send_notify) {
xen_be_send_notify(&blkdev->xendev);
}
}
static int blk_get_request(struct XenBlkDev *blkdev, struct ioreq *ioreq, RING_IDX rc)
{
switch (blkdev->protocol) {
case BLKIF_PROTOCOL_NATIVE:
memcpy(&ioreq->req, RING_GET_REQUEST(&blkdev->rings.native, rc),
sizeof(ioreq->req));
break;
case BLKIF_PROTOCOL_X86_32:
blkif_get_x86_32_req(&ioreq->req,
RING_GET_REQUEST(&blkdev->rings.x86_32_part, rc));
break;
case BLKIF_PROTOCOL_X86_64:
blkif_get_x86_64_req(&ioreq->req,
RING_GET_REQUEST(&blkdev->rings.x86_64_part, rc));
break;
}
return 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);
}
}
/* ------------------------------------------------------------- */
static void blk_bh(void *opaque)
{
struct XenBlkDev *blkdev = opaque;
blk_handle_requests(blkdev);
}
static void blk_alloc(struct XenDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
QLIST_INIT(&blkdev->inflight);
QLIST_INIT(&blkdev->finished);
QLIST_INIT(&blkdev->freelist);
blkdev->bh = qemu_bh_new(blk_bh, blkdev);
if (xen_mode != XEN_EMULATE) {
batch_maps = 1;
}
}
static int blk_init(struct XenDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
int index, qflags, have_barriers, info = 0;
char *h;
/* read xenstore entries */
if (blkdev->params == NULL) {
blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params");
h = strchr(blkdev->params, ':');
if (h != NULL) {
blkdev->fileproto = blkdev->params;
blkdev->filename = h+1;
*h = 0;
} else {
blkdev->fileproto = "<unset>";
blkdev->filename = blkdev->params;
}
}
if (blkdev->mode == NULL) {
blkdev->mode = xenstore_read_be_str(&blkdev->xendev, "mode");
}
if (blkdev->type == NULL) {
blkdev->type = xenstore_read_be_str(&blkdev->xendev, "type");
}
if (blkdev->dev == NULL) {
blkdev->dev = xenstore_read_be_str(&blkdev->xendev, "dev");
}
if (blkdev->devtype == NULL) {
blkdev->devtype = xenstore_read_be_str(&blkdev->xendev, "device-type");
}
/* do we have all we need? */
if (blkdev->params == NULL ||
blkdev->mode == NULL ||
blkdev->type == NULL ||
blkdev->dev == NULL) {
return -1;
}
/* read-only ? */
if (strcmp(blkdev->mode, "w") == 0) {
qflags = BDRV_O_RDWR;
} else {
qflags = 0;
info |= VDISK_READONLY;
}
/* cdrom ? */
if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom")) {
info |= VDISK_CDROM;
}
/* init qemu block driver */
index = (blkdev->xendev.dev - 202 * 256) / 16;
blkdev->dinfo = drive_get(IF_XEN, 0, index);
if (!blkdev->dinfo) {
/* setup via xenbus -> create new block driver instance */
xen_be_printf(&blkdev->xendev, 2, "create new bdrv (xenbus setup)\n");
blkdev->bs = bdrv_new(blkdev->dev);
if (bdrv_open(blkdev->bs, blkdev->filename, qflags,
bdrv_find_whitelisted_format(blkdev->fileproto)) != 0) {
bdrv_delete(blkdev->bs);
return -1;
}
} else {
/* setup via qemu cmdline -> already setup for us */
xen_be_printf(&blkdev->xendev, 2, "get configured bdrv (cmdline setup)\n");
blkdev->bs = blkdev->dinfo->bdrv;
}
blkdev->file_blk = BLOCK_SIZE;
blkdev->file_size = bdrv_getlength(blkdev->bs);
if (blkdev->file_size < 0) {
xen_be_printf(&blkdev->xendev, 1, "bdrv_getlength: %d (%s) | drv %s\n",
(int)blkdev->file_size, strerror(-blkdev->file_size),
blkdev->bs->drv ? blkdev->bs->drv->format_name : "-");
blkdev->file_size = 0;
}
have_barriers = blkdev->bs->drv && blkdev->bs->drv->bdrv_flush ? 1 : 0;
xen_be_printf(xendev, 1, "type \"%s\", fileproto \"%s\", filename \"%s\","
" size %" PRId64 " (%" PRId64 " MB)\n",
blkdev->type, blkdev->fileproto, blkdev->filename,
blkdev->file_size, blkdev->file_size >> 20);
/* fill info */
xenstore_write_be_int(&blkdev->xendev, "feature-barrier", have_barriers);
xenstore_write_be_int(&blkdev->xendev, "info", info);
xenstore_write_be_int(&blkdev->xendev, "sector-size", blkdev->file_blk);
xenstore_write_be_int(&blkdev->xendev, "sectors",
blkdev->file_size / blkdev->file_blk);
return 0;
}
static int blk_connect(struct XenDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
if (xenstore_read_fe_int(&blkdev->xendev, "ring-ref", &blkdev->ring_ref) == -1) {
return -1;
}
if (xenstore_read_fe_int(&blkdev->xendev, "event-channel",
&blkdev->xendev.remote_port) == -1) {
return -1;
}
blkdev->protocol = BLKIF_PROTOCOL_NATIVE;
if (blkdev->xendev.protocol) {
if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_32) == 0) {
blkdev->protocol = BLKIF_PROTOCOL_X86_32;
}
if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_64) == 0) {
blkdev->protocol = BLKIF_PROTOCOL_X86_64;
}
}
blkdev->sring = xc_gnttab_map_grant_ref(blkdev->xendev.gnttabdev,
blkdev->xendev.dom,
blkdev->ring_ref,
PROT_READ | PROT_WRITE);
if (!blkdev->sring) {
return -1;
}
blkdev->cnt_map++;
switch (blkdev->protocol) {
case BLKIF_PROTOCOL_NATIVE:
{
blkif_sring_t *sring_native = blkdev->sring;
BACK_RING_INIT(&blkdev->rings.native, sring_native, XC_PAGE_SIZE);
break;
}
case BLKIF_PROTOCOL_X86_32:
{
blkif_x86_32_sring_t *sring_x86_32 = blkdev->sring;
BACK_RING_INIT(&blkdev->rings.x86_32_part, sring_x86_32, XC_PAGE_SIZE);
break;
}
case BLKIF_PROTOCOL_X86_64:
{
blkif_x86_64_sring_t *sring_x86_64 = blkdev->sring;
BACK_RING_INIT(&blkdev->rings.x86_64_part, sring_x86_64, XC_PAGE_SIZE);
break;
}
}
xen_be_bind_evtchn(&blkdev->xendev);
xen_be_printf(&blkdev->xendev, 1, "ok: proto %s, ring-ref %d, "
"remote port %d, local port %d\n",
blkdev->xendev.protocol, blkdev->ring_ref,
blkdev->xendev.remote_port, blkdev->xendev.local_port);
return 0;
}
static void blk_disconnect(struct XenDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
if (blkdev->bs) {
if (!blkdev->dinfo) {
/* close/delete only if we created it ourself */
bdrv_close(blkdev->bs);
bdrv_delete(blkdev->bs);
}
blkdev->bs = NULL;
}
xen_be_unbind_evtchn(&blkdev->xendev);
if (blkdev->sring) {
xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
blkdev->cnt_map--;
blkdev->sring = NULL;
}
}
static int blk_free(struct XenDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
struct ioreq *ioreq;
while (!QLIST_EMPTY(&blkdev->freelist)) {
ioreq = QLIST_FIRST(&blkdev->freelist);
QLIST_REMOVE(ioreq, list);
qemu_iovec_destroy(&ioreq->v);
qemu_free(ioreq);
}
qemu_free(blkdev->params);
qemu_free(blkdev->mode);
qemu_free(blkdev->type);
qemu_free(blkdev->dev);
qemu_free(blkdev->devtype);
qemu_bh_delete(blkdev->bh);
return 0;
}
static void blk_event(struct XenDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
qemu_bh_schedule(blkdev->bh);
}
struct XenDevOps xen_blkdev_ops = {
.size = sizeof(struct XenBlkDev),
.flags = DEVOPS_FLAG_NEED_GNTDEV,
.alloc = blk_alloc,
.init = blk_init,
.connect = blk_connect,
.disconnect = blk_disconnect,
.event = blk_event,
.free = blk_free,
};
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