diff options
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/xen_backend.h | 2 | ||||
| -rw-r--r-- | hw/xen_blkif.h | 103 | ||||
| -rw-r--r-- | hw/xen_disk.c | 779 | ||||
| -rw-r--r-- | hw/xen_machine_pv.c | 1 |
4 files changed, 885 insertions, 0 deletions
diff --git a/hw/xen_backend.h b/hw/xen_backend.h index e9a4e2d..dd426dd 100644 --- a/hw/xen_backend.h +++ b/hw/xen_backend.h @@ -2,6 +2,7 @@ #define QEMU_HW_XEN_BACKEND_H 1 #include "xen_common.h" +#include "sysemu.h" /* ------------------------------------------------------------- */ @@ -87,6 +88,7 @@ void xen_be_printf(struct XenDevice *xendev, int msg_level, const char *fmt, ... extern struct XenDevOps xen_console_ops; /* xen_console.c */ extern struct XenDevOps xen_kbdmouse_ops; /* xen_framebuffer.c */ extern struct XenDevOps xen_framebuffer_ops; /* xen_framebuffer.c */ +extern struct XenDevOps xen_blkdev_ops; /* xen_disk.c */ void xen_init_display(int domid); diff --git a/hw/xen_blkif.h b/hw/xen_blkif.h new file mode 100644 index 0000000..254a5fd --- /dev/null +++ b/hw/xen_blkif.h @@ -0,0 +1,103 @@ +#ifndef __XEN_BLKIF_H__ +#define __XEN_BLKIF_H__ + +#include <xen/io/ring.h> +#include <xen/io/blkif.h> +#include <xen/io/protocols.h> + +/* Not a real protocol. Used to generate ring structs which contain + * the elements common to all protocols only. This way we get a + * compiler-checkable way to use common struct elements, so we can + * avoid using switch(protocol) in a number of places. */ +struct blkif_common_request { + char dummy; +}; +struct blkif_common_response { + char dummy; +}; + +/* i386 protocol version */ +#pragma pack(push, 4) +struct blkif_x86_32_request { + uint8_t operation; /* BLKIF_OP_??? */ + uint8_t nr_segments; /* number of segments */ + blkif_vdev_t handle; /* only for read/write requests */ + uint64_t id; /* private guest value, echoed in resp */ + blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */ + struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; +}; +struct blkif_x86_32_response { + uint64_t id; /* copied from request */ + uint8_t operation; /* copied from request */ + int16_t status; /* BLKIF_RSP_??? */ +}; +typedef struct blkif_x86_32_request blkif_x86_32_request_t; +typedef struct blkif_x86_32_response blkif_x86_32_response_t; +#pragma pack(pop) + +/* x86_64 protocol version */ +struct blkif_x86_64_request { + uint8_t operation; /* BLKIF_OP_??? */ + uint8_t nr_segments; /* number of segments */ + blkif_vdev_t handle; /* only for read/write requests */ + uint64_t __attribute__((__aligned__(8))) id; + blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */ + struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; +}; +struct blkif_x86_64_response { + uint64_t __attribute__((__aligned__(8))) id; + uint8_t operation; /* copied from request */ + int16_t status; /* BLKIF_RSP_??? */ +}; +typedef struct blkif_x86_64_request blkif_x86_64_request_t; +typedef struct blkif_x86_64_response blkif_x86_64_response_t; + +DEFINE_RING_TYPES(blkif_common, struct blkif_common_request, struct blkif_common_response); +DEFINE_RING_TYPES(blkif_x86_32, struct blkif_x86_32_request, struct blkif_x86_32_response); +DEFINE_RING_TYPES(blkif_x86_64, struct blkif_x86_64_request, struct blkif_x86_64_response); + +union blkif_back_rings { + blkif_back_ring_t native; + blkif_common_back_ring_t common; + blkif_x86_32_back_ring_t x86_32; + blkif_x86_64_back_ring_t x86_64; +}; +typedef union blkif_back_rings blkif_back_rings_t; + +enum blkif_protocol { + BLKIF_PROTOCOL_NATIVE = 1, + BLKIF_PROTOCOL_X86_32 = 2, + BLKIF_PROTOCOL_X86_64 = 3, +}; + +static void inline blkif_get_x86_32_req(blkif_request_t *dst, blkif_x86_32_request_t *src) +{ + int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST; + + dst->operation = src->operation; + dst->nr_segments = src->nr_segments; + dst->handle = src->handle; + dst->id = src->id; + dst->sector_number = src->sector_number; + if (n > src->nr_segments) + n = src->nr_segments; + for (i = 0; i < n; i++) + dst->seg[i] = src->seg[i]; +} + +static void inline blkif_get_x86_64_req(blkif_request_t *dst, blkif_x86_64_request_t *src) +{ + int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST; + + dst->operation = src->operation; + dst->nr_segments = src->nr_segments; + dst->handle = src->handle; + dst->id = src->id; + dst->sector_number = src->sector_number; + if (n > src->nr_segments) + n = src->nr_segments; + for (i = 0; i < n; i++) + dst->seg[i] = src->seg[i]; +} + +#endif /* __XEN_BLKIF_H__ */ diff --git a/hw/xen_disk.c b/hw/xen_disk.c new file mode 100644 index 0000000..527f84b --- /dev/null +++ b/hw/xen_disk.c @@ -0,0 +1,779 @@ +/* + * 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, 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" + +/* ------------------------------------------------------------- */ + +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; + 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 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->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 */ + if (BLKIF_OP_READ != ioreq->req.operation && blkdev->mode[0] != 'w') { + xen_be_printf(&blkdev->xendev, 0, "error: write req for ro device\n"); + goto err; + } + break; + case BLKIF_OP_WRITE_BARRIER: + 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; + }; + + 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) +{ + int 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) +{ + int 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_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: + 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; + + 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_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: + 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->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; + + /* 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) { + 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, + .connect = blk_connect, + .disconnect = blk_disconnect, + .event = blk_event, + .free = blk_free, +}; diff --git a/hw/xen_machine_pv.c b/hw/xen_machine_pv.c index 1f0b3ec..c764bea 100644 --- a/hw/xen_machine_pv.c +++ b/hw/xen_machine_pv.c @@ -59,6 +59,7 @@ static void xen_init_pv(ram_addr_t ram_size, int vga_ram_size, xen_be_register("console", &xen_console_ops); xen_be_register("vkbd", &xen_kbdmouse_ops); xen_be_register("vfb", &xen_framebuffer_ops); + xen_be_register("qdisk", &xen_blkdev_ops); /* setup framebuffer */ xen_init_display(xen_domid); |