--- /dev/null
+/*
+ * Block driver for the Virtual Disk Image (VDI) format
+ *
+ * Copyright (c) 2009 Stefan Weil
+ *
+ * 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, either version 2 of the License, or
+ * (at your option) version 3 or any later version.
+ *
+ * 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/>.
+ *
+ * Reference:
+ * http://forums.virtualbox.org/viewtopic.php?t=8046
+ *
+ * This driver supports create / read / write operations on VDI images.
+ *
+ * Todo (see also TODO in code):
+ *
+ * Some features like snapshots are still missing.
+ *
+ * Deallocation of zero-filled blocks and shrinking images are missing, too
+ * (might be added to common block layer).
+ *
+ * Allocation of blocks could be optimized (less writes to block map and
+ * header).
+ *
+ * Read and write of adjacents blocks could be done in one operation
+ * (current code uses one operation per block (1 MiB).
+ *
+ * The code is not thread safe (missing locks for changes in header and
+ * block table, no problem with current QEMU).
+ *
+ * Hints:
+ *
+ * Blocks (VDI documentation) correspond to clusters (QEMU).
+ * QEMU's backing files could be implemented using VDI snapshot files (TODO).
+ * VDI snapshot files may also contain the complete machine state.
+ * Maybe this machine state can be converted to QEMU PC machine snapshot data.
+ *
+ * The driver keeps a block cache (little endian entries) in memory.
+ * For the standard block size (1 MiB), a 1 TiB disk will use 4 MiB RAM,
+ * so this seems to be reasonable.
+ */
+
+#include "qemu-common.h"
+#include "block_int.h"
+#include "module.h"
+
+#if defined(HAVE_UUID_H)
+#include <uuid/uuid.h>
+#else
+/* TODO: move uuid emulation to some central place in QEMU. */
+#include "sysemu.h" /* UUID_FMT */
+typedef unsigned char uuid_t[16];
+void uuid_generate(uuid_t out);
+int uuid_is_null(const uuid_t uu);
+void uuid_unparse(const uuid_t uu, char *out);
+#endif
+
+/* Code configuration options. */
+
+/* Enable debug messages. */
+//~ #define CONFIG_VDI_DEBUG
+
+/* Support write operations on VDI images. */
+#define CONFIG_VDI_WRITE
+
+/* Support non-standard block (cluster) size. This is untested.
+ * Maybe it will be needed for very large images.
+ */
+//~ #define CONFIG_VDI_BLOCK_SIZE
+
+/* Support static (fixed, pre-allocated) images. */
+#define CONFIG_VDI_STATIC_IMAGE
+
+/* Command line option for static images. */
+#define BLOCK_OPT_STATIC "static"
+
+#define KiB 1024
+#define MiB (KiB * KiB)
+
+#define SECTOR_SIZE 512
+
+#if defined(CONFIG_VDI_DEBUG)
+#define logout(fmt, ...) \
+ fprintf(stderr, "vdi\t%-24s" fmt, __func__, ##__VA_ARGS__)
+#else
+#define logout(fmt, ...) ((void)0)
+#endif
+
+/* Image signature. */
+#define VDI_SIGNATURE 0xbeda107f
+
+/* Image version. */
+#define VDI_VERSION_1_1 0x00010001
+
+/* Image type. */
+#define VDI_TYPE_DYNAMIC 1
+#define VDI_TYPE_STATIC 2
+
+/* Innotek / SUN images use these strings in header.text:
+ * "<<< innotek VirtualBox Disk Image >>>\n"
+ * "<<< Sun xVM VirtualBox Disk Image >>>\n"
+ * "<<< Sun VirtualBox Disk Image >>>\n"
+ * The value does not matter, so QEMU created images use a different text.
+ */
+#define VDI_TEXT "<<< QEMU VM Virtual Disk Image >>>\n"
+
+/* Unallocated blocks use this index (no need to convert endianess). */
+#define VDI_UNALLOCATED UINT32_MAX
+
+#if !defined(HAVE_UUID_H)
+void uuid_generate(uuid_t out)
+{
+ memset(out, 0, sizeof(out));
+}
+
+int uuid_is_null(const uuid_t uu)
+{
+ uuid_t null_uuid = { 0 };
+ return memcmp(uu, null_uuid, sizeof(uu)) == 0;
+}
+
+void uuid_unparse(const uuid_t uu, char *out)
+{
+ snprintf(out, 37, UUID_FMT,
+ uu[0], uu[1], uu[2], uu[3], uu[4], uu[5], uu[6], uu[7],
+ uu[8], uu[9], uu[10], uu[11], uu[12], uu[13], uu[14], uu[15]);
+}
+#endif
+
+typedef struct {
+ BlockDriverAIOCB common;
+ int64_t sector_num;
+ QEMUIOVector *qiov;
+ uint8_t *buf;
+ /* Total number of sectors. */
+ int nb_sectors;
+ /* Number of sectors for current AIO. */
+ int n_sectors;
+ /* New allocated block map entry. */
+ uint32_t bmap_first;
+ uint32_t bmap_last;
+ /* Buffer for new allocated block. */
+ void *block_buffer;
+ void *orig_buf;
+ int header_modified;
+ BlockDriverAIOCB *hd_aiocb;
+ struct iovec hd_iov;
+ QEMUIOVector hd_qiov;
+ QEMUBH *bh;
+} VdiAIOCB;
+
+typedef struct {
+ char text[0x40];
+ uint32_t signature;
+ uint32_t version;
+ uint32_t header_size;
+ uint32_t image_type;
+ uint32_t image_flags;
+ char description[256];
+ uint32_t offset_bmap;
+ uint32_t offset_data;
+ uint32_t cylinders; /* disk geometry, unused here */
+ uint32_t heads; /* disk geometry, unused here */
+ uint32_t sectors; /* disk geometry, unused here */
+ uint32_t sector_size;
+ uint32_t unused1;
+ uint64_t disk_size;
+ uint32_t block_size;
+ uint32_t block_extra; /* unused here */
+ uint32_t blocks_in_image;
+ uint32_t blocks_allocated;
+ uuid_t uuid_image;
+ uuid_t uuid_last_snap;
+ uuid_t uuid_link;
+ uuid_t uuid_parent;
+ uint64_t unused2[7];
+} VdiHeader;
+
+typedef struct {
+ BlockDriverState *hd;
+ /* The block map entries are little endian (even in memory). */
+ uint32_t *bmap;
+ /* Size of block (bytes). */
+ uint32_t block_size;
+ /* Size of block (sectors). */
+ uint32_t block_sectors;
+ /* First sector of block map. */
+ uint32_t bmap_sector;
+ /* VDI header (converted to host endianess). */
+ VdiHeader header;
+} BDRVVdiState;
+
+/* Change UUID from little endian (IPRT = VirtualBox format) to big endian
+ * format (network byte order, standard, see RFC 4122) and vice versa.
+ */
+static void uuid_convert(uuid_t uuid)
+{
+ bswap32s((uint32_t *)&uuid[0]);
+ bswap16s((uint16_t *)&uuid[4]);
+ bswap16s((uint16_t *)&uuid[6]);
+}
+
+static void vdi_header_to_cpu(VdiHeader *header)
+{
+ le32_to_cpus(&header->signature);
+ le32_to_cpus(&header->version);
+ le32_to_cpus(&header->header_size);
+ le32_to_cpus(&header->image_type);
+ le32_to_cpus(&header->image_flags);
+ le32_to_cpus(&header->offset_bmap);
+ le32_to_cpus(&header->offset_data);
+ le32_to_cpus(&header->cylinders);
+ le32_to_cpus(&header->heads);
+ le32_to_cpus(&header->sectors);
+ le32_to_cpus(&header->sector_size);
+ le64_to_cpus(&header->disk_size);
+ le32_to_cpus(&header->block_size);
+ le32_to_cpus(&header->block_extra);
+ le32_to_cpus(&header->blocks_in_image);
+ le32_to_cpus(&header->blocks_allocated);
+ uuid_convert(header->uuid_image);
+ uuid_convert(header->uuid_last_snap);
+ uuid_convert(header->uuid_link);
+ uuid_convert(header->uuid_parent);
+}
+
+static void vdi_header_to_le(VdiHeader *header)
+{
+ cpu_to_le32s(&header->signature);
+ cpu_to_le32s(&header->version);
+ cpu_to_le32s(&header->header_size);
+ cpu_to_le32s(&header->image_type);
+ cpu_to_le32s(&header->image_flags);
+ cpu_to_le32s(&header->offset_bmap);
+ cpu_to_le32s(&header->offset_data);
+ cpu_to_le32s(&header->cylinders);
+ cpu_to_le32s(&header->heads);
+ cpu_to_le32s(&header->sectors);
+ cpu_to_le32s(&header->sector_size);
+ cpu_to_le64s(&header->disk_size);
+ cpu_to_le32s(&header->block_size);
+ cpu_to_le32s(&header->block_extra);
+ cpu_to_le32s(&header->blocks_in_image);
+ cpu_to_le32s(&header->blocks_allocated);
+ cpu_to_le32s(&header->blocks_allocated);
+ uuid_convert(header->uuid_image);
+ uuid_convert(header->uuid_last_snap);
+ uuid_convert(header->uuid_link);
+ uuid_convert(header->uuid_parent);
+}
+
+#if defined(CONFIG_VDI_DEBUG)
+static void vdi_header_print(VdiHeader *header)
+{
+ char uuid[37];
+ logout("text %s", header->text);
+ logout("signature 0x%04x\n", header->signature);
+ logout("header size 0x%04x\n", header->header_size);
+ logout("image type 0x%04x\n", header->image_type);
+ logout("image flags 0x%04x\n", header->image_flags);
+ logout("description %s\n", header->description);
+ logout("offset bmap 0x%04x\n", header->offset_bmap);
+ logout("offset data 0x%04x\n", header->offset_data);
+ logout("cylinders 0x%04x\n", header->cylinders);
+ logout("heads 0x%04x\n", header->heads);
+ logout("sectors 0x%04x\n", header->sectors);
+ logout("sector size 0x%04x\n", header->sector_size);
+ logout("image size 0x%" PRIx64 " B (%" PRIu64 " MiB)\n",
+ header->disk_size, header->disk_size / MiB);
+ logout("block size 0x%04x\n", header->block_size);
+ logout("block extra 0x%04x\n", header->block_extra);
+ logout("blocks tot. 0x%04x\n", header->blocks_in_image);
+ logout("blocks all. 0x%04x\n", header->blocks_allocated);
+ uuid_unparse(header->uuid_image, uuid);
+ logout("uuid image %s\n", uuid);
+ uuid_unparse(header->uuid_last_snap, uuid);
+ logout("uuid snap %s\n", uuid);
+ uuid_unparse(header->uuid_link, uuid);
+ logout("uuid link %s\n", uuid);
+ uuid_unparse(header->uuid_parent, uuid);
+ logout("uuid parent %s\n", uuid);
+}
+#endif
+
+static int vdi_check(BlockDriverState *bs)
+{
+ /* TODO: additional checks possible. */
+ BDRVVdiState *s = (BDRVVdiState *)bs->opaque;
+ int n_errors = 0;
+ uint32_t blocks_allocated = 0;
+ uint32_t block;
+ uint32_t *bmap;
+ logout("\n");
+
+ bmap = qemu_malloc(s->header.blocks_in_image * sizeof(uint32_t));
+ memset(bmap, 0xff, s->header.blocks_in_image * sizeof(uint32_t));
+
+ /* Check block map and value of blocks_allocated. */
+ for (block = 0; block < s->header.blocks_in_image; block++) {
+ uint32_t bmap_entry = le32_to_cpu(s->bmap[block]);
+ if (bmap_entry != VDI_UNALLOCATED) {
+ if (bmap_entry < s->header.blocks_in_image) {
+ blocks_allocated++;
+ if (bmap[bmap_entry] == VDI_UNALLOCATED) {
+ bmap[bmap_entry] = bmap_entry;
+ } else {
+ fprintf(stderr, "ERROR: block index %" PRIu32
+ " also used by %" PRIu32 "\n", bmap[bmap_entry], bmap_entry);
+ }
+ } else {
+ fprintf(stderr, "ERROR: block index %" PRIu32
+ " too large, is %" PRIu32 "\n", block, bmap_entry);
+ n_errors++;
+ }
+ }
+ }
+ if (blocks_allocated != s->header.blocks_allocated) {
+ fprintf(stderr, "ERROR: allocated blocks mismatch, is %" PRIu32
+ ", should be %" PRIu32 "\n",
+ blocks_allocated, s->header.blocks_allocated);
+ n_errors++;
+ }
+
+ qemu_free(bmap);
+
+ return n_errors;
+}
+
+static int vdi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
+{
+ /* TODO: vdi_get_info would be needed for machine snapshots.
+ vm_state_offset is still missing. */
+ BDRVVdiState *s = (BDRVVdiState *)bs->opaque;
+ logout("\n");
+ bdi->cluster_size = s->block_size;
+ bdi->vm_state_offset = 0;
+ return 0;
+}
+
+static int vdi_make_empty(BlockDriverState *bs)
+{
+ /* TODO: missing code. */
+ logout("\n");
+ /* The return value for missing code must be 0, see block.c. */
+ return 0;
+}
+
+static int vdi_probe(const uint8_t *buf, int buf_size, const char *filename)
+{
+ const VdiHeader *header = (const VdiHeader *)buf;
+ int result = 0;
+
+ logout("\n");
+
+ if (buf_size < sizeof(*header)) {
+ /* Header too small, no VDI. */
+ } else if (le32_to_cpu(header->signature) == VDI_SIGNATURE) {
+ result = 100;
+ }
+
+ if (result == 0) {
+ logout("no vdi image\n");
+ } else {
+ logout("%s", header->text);
+ }
+
+ return result;
+}
+
+static int vdi_open(BlockDriverState *bs, const char *filename, int flags)
+{
+ BDRVVdiState *s = bs->opaque;
+ VdiHeader header;
+ size_t bmap_size;
+ int ret;
+
+ logout("\n");
+
+ ret = bdrv_file_open(&s->hd, filename, flags);
+ if (ret < 0) {
+ return ret;
+ }
+
+ if (bdrv_read(s->hd, 0, (uint8_t *)&header, 1) < 0) {
+ goto fail;
+ }
+
+ vdi_header_to_cpu(&header);
+#if defined(CONFIG_VDI_DEBUG)
+ vdi_header_print(&header);
+#endif
+
+ if (header.version != VDI_VERSION_1_1) {
+ logout("unsupported version %u.%u\n",
+ header.version >> 16, header.version & 0xffff);
+ goto fail;
+ } else if (header.offset_bmap % SECTOR_SIZE != 0) {
+ /* We only support block maps which start on a sector boundary. */
+ logout("unsupported block map offset 0x%x B\n", header.offset_bmap);
+ goto fail;
+ } else if (header.offset_data % SECTOR_SIZE != 0) {
+ /* We only support data blocks which start on a sector boundary. */
+ logout("unsupported data offset 0x%x B\n", header.offset_data);
+ goto fail;
+ } else if (header.sector_size != SECTOR_SIZE) {
+ logout("unsupported sector size %u B\n", header.sector_size);
+ goto fail;
+ } else if (header.block_size != 1 * MiB) {
+ logout("unsupported block size %u B\n", header.block_size);
+ goto fail;
+ } else if (header.disk_size !=
+ (uint64_t)header.blocks_in_image * header.block_size) {
+ logout("unexpected block number %u B\n", header.blocks_in_image);
+ goto fail;
+ } else if (!uuid_is_null(header.uuid_link)) {
+ logout("link uuid != 0, unsupported\n");
+ goto fail;
+ } else if (!uuid_is_null(header.uuid_parent)) {
+ logout("parent uuid != 0, unsupported\n");
+ goto fail;
+ }
+
+ bs->total_sectors = header.disk_size / SECTOR_SIZE;
+
+ s->block_size = header.block_size;
+ s->block_sectors = header.block_size / SECTOR_SIZE;
+ s->bmap_sector = header.offset_bmap / SECTOR_SIZE;
+ s->header = header;
+
+ bmap_size = header.blocks_in_image * sizeof(uint32_t);
+ s->bmap = qemu_malloc(bmap_size);
+ if (bdrv_read(s->hd, s->bmap_sector,
+ (uint8_t *)s->bmap, bmap_size / SECTOR_SIZE) < 0) {
+ goto fail_free_bmap;
+ }
+
+ return 0;
+
+ fail_free_bmap:
+ qemu_free(s->bmap);
+
+ fail:
+ bdrv_delete(s->hd);
+ return -1;
+}
+
+static int vdi_is_allocated(BlockDriverState *bs, int64_t sector_num,
+ int nb_sectors, int *pnum)
+{
+ /* TODO: Check for too large sector_num (in bdrv_is_allocated or here). */
+ BDRVVdiState *s = (BDRVVdiState *)bs->opaque;
+ size_t bmap_index = sector_num / s->block_sectors;
+ size_t sector_in_block = sector_num % s->block_sectors;
+ int n_sectors = s->block_sectors - sector_in_block;
+ uint32_t bmap_entry = le32_to_cpu(s->bmap[bmap_index]);
+ logout("%p, %" PRId64 ", %d, %p\n", bs, sector_num, nb_sectors, pnum);
+ if (n_sectors > nb_sectors) {
+ n_sectors = nb_sectors;
+ }
+ *pnum = n_sectors;
+ return bmap_entry != VDI_UNALLOCATED;
+}
+
+static void vdi_aio_cancel(BlockDriverAIOCB *blockacb)
+{
+ /* TODO: This code is untested. How can I get it executed? */
+ VdiAIOCB *acb = (VdiAIOCB *)blockacb;
+ logout("\n");
+ if (acb->hd_aiocb) {
+ bdrv_aio_cancel(acb->hd_aiocb);
+ }
+ qemu_aio_release(acb);
+}
+
+static AIOPool vdi_aio_pool = {
+ .aiocb_size = sizeof(VdiAIOCB),
+ .cancel = vdi_aio_cancel,
+};
+
+static VdiAIOCB *vdi_aio_setup(BlockDriverState *bs, int64_t sector_num,
+ QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque, int is_write)
+{
+ VdiAIOCB *acb;
+
+ logout("%p, %" PRId64 ", %p, %d, %p, %p, %d\n",
+ bs, sector_num, qiov, nb_sectors, cb, opaque, is_write);
+
+ acb = qemu_aio_get(&vdi_aio_pool, bs, cb, opaque);
+ if (acb) {
+ acb->hd_aiocb = NULL;
+ acb->sector_num = sector_num;
+ acb->qiov = qiov;
+ if (qiov->niov > 1) {
+ acb->buf = qemu_blockalign(bs, qiov->size);
+ acb->orig_buf = acb->buf;
+ if (is_write) {
+ qemu_iovec_to_buffer(qiov, acb->buf);
+ }
+ } else {
+ acb->buf = (uint8_t *)qiov->iov->iov_base;
+ }
+ acb->nb_sectors = nb_sectors;
+ acb->n_sectors = 0;
+ acb->bmap_first = VDI_UNALLOCATED;
+ acb->bmap_last = VDI_UNALLOCATED;
+ acb->block_buffer = NULL;
+ acb->header_modified = 0;
+ }
+ return acb;
+}
+
+static int vdi_schedule_bh(QEMUBHFunc *cb, VdiAIOCB *acb)
+{
+ logout("\n");
+
+ if (acb->bh) {
+ return -EIO;
+ }
+
+ acb->bh = qemu_bh_new(cb, acb);
+ if (!acb->bh) {
+ return -EIO;
+ }
+
+ qemu_bh_schedule(acb->bh);
+
+ return 0;
+}
+
+static void vdi_aio_read_cb(void *opaque, int ret);
+
+static void vdi_aio_read_bh(void *opaque)
+{
+ VdiAIOCB *acb = opaque;
+ logout("\n");
+ qemu_bh_delete(acb->bh);
+ acb->bh = NULL;
+ vdi_aio_read_cb(opaque, 0);
+}
+
+static void vdi_aio_read_cb(void *opaque, int ret)
+{
+ VdiAIOCB *acb = opaque;
+ BlockDriverState *bs = acb->common.bs;
+ BDRVVdiState *s = bs->opaque;
+ uint32_t bmap_entry;
+ uint32_t block_index;
+ uint32_t sector_in_block;
+ uint32_t n_sectors;
+
+ logout("%u sectors read\n", acb->n_sectors);
+
+ acb->hd_aiocb = NULL;
+
+ if (ret < 0) {
+ goto done;
+ }
+
+ acb->nb_sectors -= acb->n_sectors;
+
+ if (acb->nb_sectors == 0) {
+ /* request completed */
+ ret = 0;
+ goto done;
+ }
+
+ acb->sector_num += acb->n_sectors;
+ acb->buf += acb->n_sectors * SECTOR_SIZE;
+
+ block_index = acb->sector_num / s->block_sectors;
+ sector_in_block = acb->sector_num % s->block_sectors;
+ n_sectors = s->block_sectors - sector_in_block;
+ if (n_sectors > acb->nb_sectors) {
+ n_sectors = acb->nb_sectors;
+ }
+
+ logout("will read %u sectors starting at sector %" PRIu64 "\n",
+ n_sectors, acb->sector_num);
+
+ /* prepare next AIO request */
+ acb->n_sectors = n_sectors;
+ bmap_entry = le32_to_cpu(s->bmap[block_index]);
+ if (bmap_entry == VDI_UNALLOCATED) {
+ /* Block not allocated, return zeros, no need to wait. */
+ memset(acb->buf, 0, n_sectors * SECTOR_SIZE);
+ ret = vdi_schedule_bh(vdi_aio_read_bh, acb);
+ if (ret < 0) {
+ goto done;
+ }
+ } else {
+ uint64_t offset = s->header.offset_data / SECTOR_SIZE +
+ (uint64_t)bmap_entry * s->block_sectors +
+ sector_in_block;
+ acb->hd_iov.iov_base = (void *)acb->buf;
+ acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE;
+ qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
+ acb->hd_aiocb = bdrv_aio_readv(s->hd, offset, &acb->hd_qiov,
+ n_sectors, vdi_aio_read_cb, acb);
+ if (acb->hd_aiocb == NULL) {
+ goto done;
+ }
+ }
+ return;
+done:
+ if (acb->qiov->niov > 1) {
+ qemu_iovec_from_buffer(acb->qiov, acb->orig_buf, acb->qiov->size);
+ qemu_vfree(acb->orig_buf);
+ }
+ acb->common.cb(acb->common.opaque, ret);
+ qemu_aio_release(acb);
+}
+
+static BlockDriverAIOCB *vdi_aio_readv(BlockDriverState *bs,
+ int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ VdiAIOCB *acb;
+ logout("\n");
+ acb = vdi_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
+ if (!acb) {
+ return NULL;
+ }
+ vdi_aio_read_cb(acb, 0);
+ return &acb->common;
+}
+
+static void vdi_aio_write_cb(void *opaque, int ret)
+{
+ VdiAIOCB *acb = opaque;
+ BlockDriverState *bs = acb->common.bs;
+ BDRVVdiState *s = bs->opaque;
+ uint32_t bmap_entry;
+ uint32_t block_index;
+ uint32_t sector_in_block;
+ uint32_t n_sectors;
+
+ acb->hd_aiocb = NULL;
+
+ if (ret < 0) {
+ goto done;
+ }
+
+ acb->nb_sectors -= acb->n_sectors;
+ acb->sector_num += acb->n_sectors;
+ acb->buf += acb->n_sectors * SECTOR_SIZE;
+
+ if (acb->nb_sectors == 0) {
+ logout("finished data write\n");
+ acb->n_sectors = 0;
+ if (acb->header_modified) {
+ VdiHeader *header = acb->block_buffer;
+ logout("now writing modified header\n");
+ assert(acb->bmap_first != VDI_UNALLOCATED);
+ *header = s->header;
+ vdi_header_to_le(header);
+ acb->header_modified = 0;
+ acb->hd_iov.iov_base = acb->block_buffer;
+ acb->hd_iov.iov_len = SECTOR_SIZE;
+ qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
+ acb->hd_aiocb = bdrv_aio_writev(s->hd, 0, &acb->hd_qiov, 1,
+ vdi_aio_write_cb, acb);
+ if (acb->hd_aiocb == NULL) {
+ goto done;
+ }
+ return;
+ } else if (acb->bmap_first != VDI_UNALLOCATED) {
+ /* One or more new blocks were allocated. */
+ uint64_t offset;
+ uint32_t bmap_first;
+ uint32_t bmap_last;
+ qemu_free(acb->block_buffer);
+ acb->block_buffer = NULL;
+ bmap_first = acb->bmap_first;
+ bmap_last = acb->bmap_last;
+ logout("now writing modified block map entry %u...%u\n",
+ bmap_first, bmap_last);
+ /* Write modified sectors from block map. */
+ bmap_first /= (SECTOR_SIZE / sizeof(uint32_t));
+ bmap_last /= (SECTOR_SIZE / sizeof(uint32_t));
+ n_sectors = bmap_last - bmap_first + 1;
+ offset = s->bmap_sector + bmap_first;
+ acb->bmap_first = VDI_UNALLOCATED;
+ acb->hd_iov.iov_base = (uint8_t *)&s->bmap[0] +
+ bmap_first * SECTOR_SIZE;
+ acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE;
+ qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
+ logout("will write %u block map sectors starting from entry %u\n",
+ n_sectors, bmap_first);
+ acb->hd_aiocb = bdrv_aio_writev(s->hd, offset, &acb->hd_qiov,
+ n_sectors, vdi_aio_write_cb, acb);
+ if (acb->hd_aiocb == NULL) {
+ goto done;
+ }
+ return;
+ }
+ ret = 0;
+ goto done;
+ }
+
+ logout("%u sectors written\n", acb->n_sectors);
+
+ block_index = acb->sector_num / s->block_sectors;
+ sector_in_block = acb->sector_num % s->block_sectors;
+ n_sectors = s->block_sectors - sector_in_block;
+ if (n_sectors > acb->nb_sectors) {
+ n_sectors = acb->nb_sectors;
+ }
+
+ logout("will write %u sectors starting at sector %" PRIu64 "\n",
+ n_sectors, acb->sector_num);
+
+ /* prepare next AIO request */
+ acb->n_sectors = n_sectors;
+ bmap_entry = le32_to_cpu(s->bmap[block_index]);
+ if (bmap_entry == VDI_UNALLOCATED) {
+ /* Allocate new block and write to it. */
+ uint64_t offset;
+ uint8_t *block;
+ bmap_entry = s->header.blocks_allocated;
+ s->bmap[block_index] = cpu_to_le32(bmap_entry);
+ s->header.blocks_allocated++;
+ offset = s->header.offset_data / SECTOR_SIZE +
+ (uint64_t)bmap_entry * s->block_sectors;
+ block = acb->block_buffer;
+ if (block == NULL) {
+ block = qemu_mallocz(s->block_size);
+ acb->block_buffer = block;
+ acb->bmap_first = block_index;
+ assert(!acb->header_modified);
+ acb->header_modified = 1;
+ }
+ acb->bmap_last = block_index;
+ memcpy(block + sector_in_block * SECTOR_SIZE,
+ acb->buf, n_sectors * SECTOR_SIZE);
+ acb->hd_iov.iov_base = block;
+ acb->hd_iov.iov_len = s->block_size;
+ qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
+ acb->hd_aiocb = bdrv_aio_writev(s->hd, offset,
+ &acb->hd_qiov, s->block_sectors,
+ vdi_aio_write_cb, acb);
+ if (acb->hd_aiocb == NULL) {
+ goto done;
+ }
+ } else {
+ uint64_t offset = s->header.offset_data / SECTOR_SIZE +
+ (uint64_t)bmap_entry * s->block_sectors +
+ sector_in_block;
+ acb->hd_iov.iov_base = acb->buf;
+ acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE;
+ qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
+ acb->hd_aiocb = bdrv_aio_writev(s->hd, offset, &acb->hd_qiov,
+ n_sectors, vdi_aio_write_cb, acb);
+ if (acb->hd_aiocb == NULL) {
+ goto done;
+ }
+ }
+
+ return;
+
+done:
+ if (acb->qiov->niov > 1) {
+ qemu_vfree(acb->orig_buf);
+ }
+ acb->common.cb(acb->common.opaque, ret);
+ qemu_aio_release(acb);
+}
+
+static BlockDriverAIOCB *vdi_aio_writev(BlockDriverState *bs,
+ int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ VdiAIOCB *acb;
+ logout("\n");
+ acb = vdi_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
+ if (!acb) {
+ return NULL;
+ }
+ vdi_aio_write_cb(acb, 0);
+ return &acb->common;
+}
+
+static int vdi_create(const char *filename, QEMUOptionParameter *options)
+{
+ int fd;
+ int result = 0;
+ uint64_t bytes = 0;
+ uint32_t blocks;
+ size_t block_size = 1 * MiB;
+ uint32_t image_type = VDI_TYPE_DYNAMIC;
+ VdiHeader header;
+ size_t i;
+ size_t bmap_size;
+ uint32_t *bmap;
+
+ logout("\n");
+
+ /* Read out options. */
+ while (options && options->name) {
+ if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
+ bytes = options->value.n;
+#if defined(CONFIG_VDI_BLOCK_SIZE)
+ } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) {
+ if (options->value.n) {
+ /* TODO: Additional checks (SECTOR_SIZE * 2^n, ...). */
+ block_size = options->value.n;
+ }
+#endif
+#if defined(CONFIG_VDI_STATIC_IMAGE)
+ } else if (!strcmp(options->name, BLOCK_OPT_STATIC)) {
+ image_type = VDI_TYPE_STATIC;
+#endif
+ }
+ options++;
+ }
+
+ fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE,
+ 0644);
+ if (fd < 0) {
+ return -errno;
+ }
+
+ blocks = bytes / block_size;
+ bmap_size = blocks * sizeof(uint32_t);
+ bmap_size = ((bmap_size + SECTOR_SIZE - 1) & ~(SECTOR_SIZE -1));
+
+ memset(&header, 0, sizeof(header));
+ strcpy(header.text, VDI_TEXT);
+ header.signature = VDI_SIGNATURE;
+ header.version = VDI_VERSION_1_1;
+ header.header_size = 0x180;
+ header.image_type = image_type;
+ header.offset_bmap = 0x200;
+ header.offset_data = 0x200 + bmap_size;
+ header.sector_size = SECTOR_SIZE;
+ header.disk_size = bytes;
+ header.block_size = block_size;
+ header.blocks_in_image = blocks;
+ uuid_generate(header.uuid_image);
+ uuid_generate(header.uuid_last_snap);
+ /* There is no need to set header.uuid_link or header.uuid_parent here. */
+#if defined(CONFIG_VDI_DEBUG)
+ vdi_header_print(&header);
+#endif
+ vdi_header_to_le(&header);
+ if (write(fd, &header, sizeof(header)) < 0) {
+ result = -errno;
+ }
+
+ bmap = (uint32_t *)qemu_mallocz(bmap_size);
+ for (i = 0; i < blocks; i++) {
+ if (image_type == VDI_TYPE_STATIC) {
+ bmap[i] = i;
+ } else {
+ bmap[i] = VDI_UNALLOCATED;
+ }
+ }
+ if (write(fd, bmap, bmap_size) < 0) {
+ result = -errno;
+ }
+ qemu_free(bmap);
+ if (image_type == VDI_TYPE_STATIC) {
+ if (ftruncate(fd, sizeof(header) + bmap_size + blocks * block_size)) {
+ result = -errno;
+ }
+ }
+
+ if (close(fd) < 0) {
+ result = -errno;
+ }
+
+ return result;
+}
+
+static void vdi_close(BlockDriverState *bs)
+{
+ BDRVVdiState *s = bs->opaque;
+ logout("\n");
+ bdrv_delete(s->hd);
+}
+
+static void vdi_flush(BlockDriverState *bs)
+{
+ BDRVVdiState *s = bs->opaque;
+ logout("\n");
+ bdrv_flush(s->hd);
+}
+
+
+static QEMUOptionParameter vdi_create_options[] = {
+ {
+ .name = BLOCK_OPT_SIZE,
+ .type = OPT_SIZE,
+ .help = "Virtual disk size"
+ },
+#if defined(CONFIG_VDI_BLOCK_SIZE)
+ {
+ .name = BLOCK_OPT_CLUSTER_SIZE,
+ .type = OPT_SIZE,
+ .help = "VDI cluster (block) size"
+ },
+#endif
+#if defined(CONFIG_VDI_STATIC_IMAGE)
+ {
+ .name = BLOCK_OPT_STATIC,
+ .type = OPT_FLAG,
+ .help = "VDI static (pre-allocated) image"
+ },
+#endif
+ /* TODO: An additional option to set UUID values might be useful. */
+ { NULL }
+};
+
+static BlockDriver bdrv_vdi = {
+ .format_name = "vdi",
+ .instance_size = sizeof(BDRVVdiState),
+ .bdrv_probe = vdi_probe,
+ .bdrv_open = vdi_open,
+ .bdrv_close = vdi_close,
+ .bdrv_create = vdi_create,
+ .bdrv_flush = vdi_flush,
+ .bdrv_is_allocated = vdi_is_allocated,
+ .bdrv_make_empty = vdi_make_empty,
+
+ .bdrv_aio_readv = vdi_aio_readv,
+#if defined(CONFIG_VDI_WRITE)
+ .bdrv_aio_writev = vdi_aio_writev,
+#endif
+
+ .bdrv_get_info = vdi_get_info,
+
+ .create_options = vdi_create_options,
+ .bdrv_check = vdi_check,
+};
+
+static void bdrv_vdi_init(void)
+{
+ logout("\n");
+ bdrv_register(&bdrv_vdi);
+}
+
+block_init(bdrv_vdi_init);
projects / sdk / emulator / qemu.git / commitdiff