diff options
Diffstat (limited to 'hw/xen_disk.c')
| -rw-r--r-- | hw/xen_disk.c | 972 |
1 files changed, 0 insertions, 972 deletions
diff --git a/hw/xen_disk.c b/hw/xen_disk.c deleted file mode 100644 index 47a51cf014..0000000000 --- a/hw/xen_disk.c +++ /dev/null @@ -1,972 +0,0 @@ -/* - * 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/>. - * - * Contributions after 2012-01-13 are licensed under the terms of the - * GNU GPL, version 2 or (at your option) any later version. - */ - -#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 "hw/hw.h" -#include "hw/xen_backend.h" -#include "hw/xen_blkif.h" -#include "sysemu/blockdev.h" - -/* ------------------------------------------------------------- */ - -static int batch_maps = 0; - -static int max_requests = 32; - -/* ------------------------------------------------------------- */ - -#define BLOCK_SIZE 512 -#define IOCB_COUNT (BLKIF_MAX_SEGMENTS_PER_REQUEST + 2) - -struct PersistentGrant { - void *page; - struct XenBlkDev *blkdev; -}; - -typedef struct PersistentGrant PersistentGrant; - -struct ioreq { - blkif_request_t req; - int16_t status; - - /* parsed request */ - off_t start; - QEMUIOVector v; - int presync; - int postsync; - uint8_t mapped; - - /* 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; - int num_unmap; - - /* aio status */ - int aio_inflight; - int aio_errors; - - struct XenBlkDev *blkdev; - QLIST_ENTRY(ioreq) list; - BlockAcctCookie acct; -}; - -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; - - /* Persistent grants extension */ - gboolean feature_persistent; - GTree *persistent_gnts; - unsigned int persistent_gnt_count; - unsigned int max_grants; - - /* qemu block driver */ - DriveInfo *dinfo; - 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 gint int_cmp(gconstpointer a, gconstpointer b, gpointer user_data) -{ - uint ua = GPOINTER_TO_UINT(a); - uint ub = GPOINTER_TO_UINT(b); - return (ua > ub) - (ua < ub); -} - -static void destroy_grant(gpointer pgnt) -{ - PersistentGrant *grant = pgnt; - XenGnttab gnt = grant->blkdev->xendev.gnttabdev; - - if (xc_gnttab_munmap(gnt, grant->page, 1) != 0) { - xen_be_printf(&grant->blkdev->xendev, 0, - "xc_gnttab_munmap failed: %s\n", - strerror(errno)); - } - grant->blkdev->persistent_gnt_count--; - xen_be_printf(&grant->blkdev->xendev, 3, - "unmapped grant %p\n", grant->page); - g_free(grant); -} - -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 = g_malloc0(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); - } - 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, bool finish) -{ - struct XenBlkDev *blkdev = ioreq->blkdev; - - QLIST_REMOVE(ioreq, list); - ioreq_reset(ioreq); - ioreq->blkdev = blkdev; - QLIST_INSERT_HEAD(&blkdev->freelist, ioreq, list); - if (finish) { - blkdev->requests_finished--; - } else { - blkdev->requests_inflight--; - } -} - -/* - * 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_FLUSH_DISKCACHE: - ioreq->presync = 1; - if (!ioreq->req.nr_segments) { - return 0; - } - /* fall through */ - case BLKIF_OP_WRITE: - ioreq->prot = PROT_READ; /* from memory */ - 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->num_unmap == 0 || ioreq->mapped == 0) { - return; - } - if (batch_maps) { - if (!ioreq->pages) { - return; - } - if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->num_unmap) != 0) { - xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n", - strerror(errno)); - } - ioreq->blkdev->cnt_map -= ioreq->num_unmap; - ioreq->pages = NULL; - } else { - for (i = 0; i < ioreq->num_unmap; 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; - } - } - ioreq->mapped = 0; -} - -static int ioreq_map(struct ioreq *ioreq) -{ - XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev; - uint32_t domids[BLKIF_MAX_SEGMENTS_PER_REQUEST]; - uint32_t refs[BLKIF_MAX_SEGMENTS_PER_REQUEST]; - void *page[BLKIF_MAX_SEGMENTS_PER_REQUEST]; - int i, j, new_maps = 0; - PersistentGrant *grant; - /* domids and refs variables will contain the information necessary - * to map the grants that are needed to fulfill this request. - * - * After mapping the needed grants, the page array will contain the - * memory address of each granted page in the order specified in ioreq - * (disregarding if it's a persistent grant or not). - */ - - if (ioreq->v.niov == 0 || ioreq->mapped == 1) { - return 0; - } - if (ioreq->blkdev->feature_persistent) { - for (i = 0; i < ioreq->v.niov; i++) { - grant = g_tree_lookup(ioreq->blkdev->persistent_gnts, - GUINT_TO_POINTER(ioreq->refs[i])); - - if (grant != NULL) { - page[i] = grant->page; - xen_be_printf(&ioreq->blkdev->xendev, 3, - "using persistent-grant %" PRIu32 "\n", - ioreq->refs[i]); - } else { - /* Add the grant to the list of grants that - * should be mapped - */ - domids[new_maps] = ioreq->domids[i]; - refs[new_maps] = ioreq->refs[i]; - page[i] = NULL; - new_maps++; - } - } - /* Set the protection to RW, since grants may be reused later - * with a different protection than the one needed for this request - */ - ioreq->prot = PROT_WRITE | PROT_READ; - } else { - /* All grants in the request should be mapped */ - memcpy(refs, ioreq->refs, sizeof(refs)); - memcpy(domids, ioreq->domids, sizeof(domids)); - memset(page, 0, sizeof(page)); - new_maps = ioreq->v.niov; - } - - if (batch_maps && new_maps) { - ioreq->pages = xc_gnttab_map_grant_refs - (gnt, new_maps, domids, refs, ioreq->prot); - if (ioreq->pages == NULL) { - xen_be_printf(&ioreq->blkdev->xendev, 0, - "can't map %d grant refs (%s, %d maps)\n", - new_maps, strerror(errno), ioreq->blkdev->cnt_map); - return -1; - } - for (i = 0, j = 0; i < ioreq->v.niov; i++) { - if (page[i] == NULL) { - page[i] = ioreq->pages + (j++) * XC_PAGE_SIZE; - } - } - ioreq->blkdev->cnt_map += new_maps; - } else if (new_maps) { - for (i = 0; i < new_maps; i++) { - ioreq->page[i] = xc_gnttab_map_grant_ref - (gnt, domids[i], 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", - refs[i], strerror(errno), ioreq->blkdev->cnt_map); - ioreq_unmap(ioreq); - return -1; - } - ioreq->blkdev->cnt_map++; - } - for (i = 0, j = 0; i < ioreq->v.niov; i++) { - if (page[i] == NULL) { - page[i] = ioreq->page[j++]; - } - } - } - if (ioreq->blkdev->feature_persistent) { - while ((ioreq->blkdev->persistent_gnt_count < ioreq->blkdev->max_grants) - && new_maps) { - /* Go through the list of newly mapped grants and add as many - * as possible to the list of persistently mapped grants. - * - * Since we start at the end of ioreq->page(s), we only need - * to decrease new_maps to prevent this granted pages from - * being unmapped in ioreq_unmap. - */ - grant = g_malloc0(sizeof(*grant)); - new_maps--; - if (batch_maps) { - grant->page = ioreq->pages + (new_maps) * XC_PAGE_SIZE; - } else { - grant->page = ioreq->page[new_maps]; - } - grant->blkdev = ioreq->blkdev; - xen_be_printf(&ioreq->blkdev->xendev, 3, - "adding grant %" PRIu32 " page: %p\n", - refs[new_maps], grant->page); - g_tree_insert(ioreq->blkdev->persistent_gnts, - GUINT_TO_POINTER(refs[new_maps]), - grant); - ioreq->blkdev->persistent_gnt_count++; - } - } - for (i = 0; i < ioreq->v.niov; i++) { - ioreq->v.iov[i].iov_base += (uintptr_t)page[i]; - } - ioreq->mapped = 1; - ioreq->num_unmap = new_maps; - return 0; -} - -static int ioreq_runio_qemu_aio(struct ioreq *ioreq); - -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->presync) { - ioreq->presync = 0; - ioreq_runio_qemu_aio(ioreq); - return; - } - if (ioreq->aio_inflight > 0) { - return; - } - if (ioreq->postsync) { - ioreq->postsync = 0; - ioreq->aio_inflight++; - bdrv_aio_flush(ioreq->blkdev->bs, qemu_aio_complete, ioreq); - return; - } - - ioreq->status = ioreq->aio_errors ? BLKIF_RSP_ERROR : BLKIF_RSP_OKAY; - ioreq_unmap(ioreq); - ioreq_finish(ioreq); - bdrv_acct_done(ioreq->blkdev->bs, &ioreq->acct); - 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_aio_flush(ioreq->blkdev->bs, qemu_aio_complete, ioreq); - return 0; - } - - switch (ioreq->req.operation) { - case BLKIF_OP_READ: - bdrv_acct_start(blkdev->bs, &ioreq->acct, ioreq->v.size, BDRV_ACCT_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_FLUSH_DISKCACHE: - if (!ioreq->req.nr_segments) { - break; - } - - bdrv_acct_start(blkdev->bs, &ioreq->acct, ioreq->v.size, BDRV_ACCT_WRITE); - 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_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, true); - } - 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'. */ - - 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, false); - continue; - } - - ioreq_runio_qemu_aio(ioreq); - } - - 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); -} - -/* - * We need to account for the grant allocations requiring contiguous - * chunks; the worst case number would be - * max_req * max_seg + (max_req - 1) * (max_seg - 1) + 1, - * but in order to keep things simple just use - * 2 * max_req * max_seg. - */ -#define MAX_GRANTS(max_req, max_seg) (2 * (max_req) * (max_seg)) - -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; - } - if (xc_gnttab_set_max_grants(xendev->gnttabdev, - MAX_GRANTS(max_requests, BLKIF_MAX_SEGMENTS_PER_REQUEST)) < 0) { - xen_be_printf(xendev, 0, "xc_gnttab_set_max_grants failed: %s\n", - strerror(errno)); - } -} - -static int blk_init(struct XenDevice *xendev) -{ - struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); - int info = 0; - - /* read xenstore entries */ - if (blkdev->params == NULL) { - char *h = 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) { - goto out_error; - } - - /* read-only ? */ - if (strcmp(blkdev->mode, "w")) { - info |= VDISK_READONLY; - } - - /* cdrom ? */ - if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom")) { - info |= VDISK_CDROM; - } - - blkdev->file_blk = BLOCK_SIZE; - - /* fill info - * blk_connect supplies sector-size and sectors - */ - xenstore_write_be_int(&blkdev->xendev, "feature-flush-cache", 1); - xenstore_write_be_int(&blkdev->xendev, "feature-persistent", 1); - xenstore_write_be_int(&blkdev->xendev, "info", info); - return 0; - -out_error: - g_free(blkdev->params); - blkdev->params = NULL; - g_free(blkdev->mode); - blkdev->mode = NULL; - g_free(blkdev->type); - blkdev->type = NULL; - g_free(blkdev->dev); - blkdev->dev = NULL; - g_free(blkdev->devtype); - blkdev->devtype = NULL; - return -1; -} - -static int blk_connect(struct XenDevice *xendev) -{ - struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); - int pers, index, qflags; - - /* read-only ? */ - qflags = BDRV_O_CACHE_WB | BDRV_O_NATIVE_AIO; - if (strcmp(blkdev->mode, "w") == 0) { - qflags |= BDRV_O_RDWR; - } - - /* 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 (blkdev->bs) { - if (bdrv_open(blkdev->bs, blkdev->filename, NULL, qflags, - bdrv_find_whitelisted_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 = blkdev->dinfo->bdrv; - } - bdrv_attach_dev_nofail(blkdev->bs, blkdev); - 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), - bdrv_get_format_name(blkdev->bs) ?: "-"); - blkdev->file_size = 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 in number of sector size and number of sectors */ - xenstore_write_be_int(&blkdev->xendev, "sector-size", blkdev->file_blk); - xenstore_write_be_int64(&blkdev->xendev, "sectors", - blkdev->file_size / blkdev->file_blk); - - 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; - } - if (xenstore_read_fe_int(&blkdev->xendev, "feature-persistent", &pers)) { - blkdev->feature_persistent = FALSE; - } else { - blkdev->feature_persistent = !!pers; - } - - 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; - } - } - - if (blkdev->feature_persistent) { - /* Init persistent grants */ - blkdev->max_grants = max_requests * BLKIF_MAX_SEGMENTS_PER_REQUEST; - blkdev->persistent_gnts = g_tree_new_full((GCompareDataFunc)int_cmp, - NULL, NULL, - (GDestroyNotify)destroy_grant); - blkdev->persistent_gnt_count = 0; - } - - 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_detach_dev(blkdev->bs, blkdev); - 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; - - if (blkdev->bs || blkdev->sring) { - blk_disconnect(xendev); - } - - /* Free persistent grants */ - if (blkdev->feature_persistent) { - g_tree_destroy(blkdev->persistent_gnts); - } - - while (!QLIST_EMPTY(&blkdev->freelist)) { - ioreq = QLIST_FIRST(&blkdev->freelist); - QLIST_REMOVE(ioreq, list); - qemu_iovec_destroy(&ioreq->v); - g_free(ioreq); - } - - g_free(blkdev->params); - g_free(blkdev->mode); - g_free(blkdev->type); - g_free(blkdev->dev); - g_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, -}; |