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- /*
- * xen paravirt block device backend
- *
- * (c) Gerd Hoffmann <[email protected]>
- *
- * 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, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- */
- #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 "sysemu.h"
- /* ------------------------------------------------------------- */
- static int syncwrite = 0;
- static int batch_maps = 1;
- 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;
- LIST_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 */
- LIST_HEAD(inflight_head, ioreq) inflight;
- LIST_HEAD(finished_head, ioreq) finished;
- LIST_HEAD(freelist_head, ioreq) freelist;
- int requests_total;
- int requests_inflight;
- int requests_finished;
- /* qemu block driver */
- int index;
- BlockDriverState *bs;
- QEMUBH *bh;
- };
- /* ------------------------------------------------------------- */
- static void ioreq_reset(struct ioreq *ioreq)
- {
- memset(&ioreq->req, 0, sizeof(ioreq->req));
- ioreq->status = 0;
- ioreq->start = 0;
- ioreq->presync = 0;
- ioreq->postsync = 0;
- ioreq->mapped = 0;
- memset(ioreq->domids, 0, sizeof(ioreq->domids));
- memset(ioreq->refs, 0, sizeof(ioreq->refs));
- ioreq->prot = 0;
- memset(ioreq->page, 0, sizeof(ioreq->page));
- ioreq->pages = NULL;
- ioreq->aio_inflight = 0;
- ioreq->aio_errors = 0;
- ioreq->blkdev = NULL;
- memset(&ioreq->list, 0, sizeof(ioreq->list));
- memset(&ioreq->acct, 0, sizeof(ioreq->acct));
- qemu_iovec_reset(&ioreq->v);
- }
- static struct ioreq *ioreq_start(struct XenBlkDev *blkdev)
- {
- struct ioreq *ioreq = NULL;
- if (LIST_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 = LIST_FIRST(&blkdev->freelist);
- LIST_REMOVE(ioreq, list);
- qemu_iovec_reset(&ioreq->v);
- }
- LIST_INSERT_HEAD(&blkdev->inflight, ioreq, list);
- blkdev->requests_inflight++;
- out:
- return ioreq;
- }
- static void ioreq_finish(struct ioreq *ioreq)
- {
- struct XenBlkDev *blkdev = ioreq->blkdev;
- LIST_REMOVE(ioreq, list);
- LIST_INSERT_HEAD(&blkdev->finished, ioreq, list);
- blkdev->requests_inflight--;
- blkdev->requests_finished++;
- }
- static void ioreq_release(struct ioreq *ioreq)
- {
- struct XenBlkDev *blkdev = ioreq->blkdev;
- LIST_REMOVE(ioreq, list);
- /*memset(ioreq, 0, sizeof(*ioreq)); */
- ioreq_reset(ioreq);
- ioreq->blkdev = blkdev;
- LIST_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)
- {
- xc_gnttab *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)
- {
- xc_gnttab *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;
- 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->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;
- if (ioreq->postsync)
- bdrv_flush(ioreq->blkdev->bs);
- 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;
- 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;
- }
- qemu_aio_complete(ioreq, 0);
- return 0;
- err:
- 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, blkdev->rings.x86_32.rsp_prod_pvt);
- break;
- case BLKIF_PROTOCOL_X86_64:
- dst = RING_GET_RESPONSE(&blkdev->rings.x86_64, blkdev->rings.x86_64.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 (!LIST_EMPTY(&blkdev->finished)) {
- ioreq = LIST_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, rc));
- break;
- case BLKIF_PROTOCOL_X86_64:
- blkif_get_x86_64_req(&ioreq->req, RING_GET_REQUEST(&blkdev->rings.x86_64, 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);
- LIST_INIT(&blkdev->inflight);
- LIST_INIT(&blkdev->finished);
- LIST_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 mode, qflags, have_barriers, info = 0;
- char *h = NULL;
- /* read xenstore entries */
- if (blkdev->params == NULL) {
- blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params");
- if (blkdev->params != NULL)
- 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 (!strcmp("aio", blkdev->fileproto))
- blkdev->fileproto = "raw";
- 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 ? */
- qflags = BDRV_O_NOCACHE;
- if (strcmp(blkdev->mode, "w") == 0) {
- mode = O_RDWR;
- qflags |= BDRV_O_RDWR;
- } else {
- mode = O_RDONLY;
- qflags |= BDRV_O_RDONLY;
- info |= VDISK_READONLY;
- }
- /* cdrom ? */
- if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom"))
- info |= VDISK_CDROM;
- /* init qemu block driver */
- blkdev->index = (blkdev->xendev.dev - 202 * 256) / 16;
- blkdev->index = drive_get_index(IF_XEN, 0, blkdev->index);
- if (blkdev->index == -1) {
- /* 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 (blkdev->bs) {
- if (bdrv_open2(blkdev->bs, blkdev->filename, qflags,
- bdrv_find_format(blkdev->fileproto)) != 0) {
- bdrv_delete(blkdev->bs);
- blkdev->bs = NULL;
- }
- }
- if (!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 = drives_table[blkdev->index].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, 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, 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->index == -1) {
- /* 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 (!LIST_EMPTY(&blkdev->freelist)) {
- ioreq = LIST_FIRST(&blkdev->freelist);
- LIST_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,
- .initialise = blk_connect,
- .disconnect = blk_disconnect,
- .event = blk_event,
- .free = blk_free,
- };
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