From e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb Mon Sep 17 00:00:00 2001 From: Yang Zhang Date: Fri, 28 Aug 2015 09:58:54 +0800 Subject: Add qemu 2.4.0 Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang --- qemu/block/bochs.c | 277 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 277 insertions(+) create mode 100644 qemu/block/bochs.c (limited to 'qemu/block/bochs.c') diff --git a/qemu/block/bochs.c b/qemu/block/bochs.c new file mode 100644 index 000000000..199ac2b9a --- /dev/null +++ b/qemu/block/bochs.c @@ -0,0 +1,277 @@ +/* + * Block driver for the various disk image formats used by Bochs + * Currently only for "growing" type in read-only mode + * + * Copyright (c) 2005 Alex Beregszaszi + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#include "qemu-common.h" +#include "block/block_int.h" +#include "qemu/module.h" + +/**************************************************************/ + +#define HEADER_MAGIC "Bochs Virtual HD Image" +#define HEADER_VERSION 0x00020000 +#define HEADER_V1 0x00010000 +#define HEADER_SIZE 512 + +#define REDOLOG_TYPE "Redolog" +#define GROWING_TYPE "Growing" + +// not allocated: 0xffffffff + +// always little-endian +struct bochs_header { + char magic[32]; /* "Bochs Virtual HD Image" */ + char type[16]; /* "Redolog" */ + char subtype[16]; /* "Undoable" / "Volatile" / "Growing" */ + uint32_t version; + uint32_t header; /* size of header */ + + uint32_t catalog; /* num of entries */ + uint32_t bitmap; /* bitmap size */ + uint32_t extent; /* extent size */ + + union { + struct { + uint32_t reserved; /* for ??? */ + uint64_t disk; /* disk size */ + char padding[HEADER_SIZE - 64 - 20 - 12]; + } QEMU_PACKED redolog; + struct { + uint64_t disk; /* disk size */ + char padding[HEADER_SIZE - 64 - 20 - 8]; + } QEMU_PACKED redolog_v1; + char padding[HEADER_SIZE - 64 - 20]; + } extra; +} QEMU_PACKED; + +typedef struct BDRVBochsState { + CoMutex lock; + uint32_t *catalog_bitmap; + uint32_t catalog_size; + + uint32_t data_offset; + + uint32_t bitmap_blocks; + uint32_t extent_blocks; + uint32_t extent_size; +} BDRVBochsState; + +static int bochs_probe(const uint8_t *buf, int buf_size, const char *filename) +{ + const struct bochs_header *bochs = (const void *)buf; + + if (buf_size < HEADER_SIZE) + return 0; + + if (!strcmp(bochs->magic, HEADER_MAGIC) && + !strcmp(bochs->type, REDOLOG_TYPE) && + !strcmp(bochs->subtype, GROWING_TYPE) && + ((le32_to_cpu(bochs->version) == HEADER_VERSION) || + (le32_to_cpu(bochs->version) == HEADER_V1))) + return 100; + + return 0; +} + +static int bochs_open(BlockDriverState *bs, QDict *options, int flags, + Error **errp) +{ + BDRVBochsState *s = bs->opaque; + uint32_t i; + struct bochs_header bochs; + int ret; + + bs->read_only = 1; // no write support yet + + ret = bdrv_pread(bs->file, 0, &bochs, sizeof(bochs)); + if (ret < 0) { + return ret; + } + + if (strcmp(bochs.magic, HEADER_MAGIC) || + strcmp(bochs.type, REDOLOG_TYPE) || + strcmp(bochs.subtype, GROWING_TYPE) || + ((le32_to_cpu(bochs.version) != HEADER_VERSION) && + (le32_to_cpu(bochs.version) != HEADER_V1))) { + error_setg(errp, "Image not in Bochs format"); + return -EINVAL; + } + + if (le32_to_cpu(bochs.version) == HEADER_V1) { + bs->total_sectors = le64_to_cpu(bochs.extra.redolog_v1.disk) / 512; + } else { + bs->total_sectors = le64_to_cpu(bochs.extra.redolog.disk) / 512; + } + + /* Limit to 1M entries to avoid unbounded allocation. This is what is + * needed for the largest image that bximage can create (~8 TB). */ + s->catalog_size = le32_to_cpu(bochs.catalog); + if (s->catalog_size > 0x100000) { + error_setg(errp, "Catalog size is too large"); + return -EFBIG; + } + + s->catalog_bitmap = g_try_new(uint32_t, s->catalog_size); + if (s->catalog_size && s->catalog_bitmap == NULL) { + error_setg(errp, "Could not allocate memory for catalog"); + return -ENOMEM; + } + + ret = bdrv_pread(bs->file, le32_to_cpu(bochs.header), s->catalog_bitmap, + s->catalog_size * 4); + if (ret < 0) { + goto fail; + } + + for (i = 0; i < s->catalog_size; i++) + le32_to_cpus(&s->catalog_bitmap[i]); + + s->data_offset = le32_to_cpu(bochs.header) + (s->catalog_size * 4); + + s->bitmap_blocks = 1 + (le32_to_cpu(bochs.bitmap) - 1) / 512; + s->extent_blocks = 1 + (le32_to_cpu(bochs.extent) - 1) / 512; + + s->extent_size = le32_to_cpu(bochs.extent); + if (s->extent_size < BDRV_SECTOR_SIZE) { + /* bximage actually never creates extents smaller than 4k */ + error_setg(errp, "Extent size must be at least 512"); + ret = -EINVAL; + goto fail; + } else if (!is_power_of_2(s->extent_size)) { + error_setg(errp, "Extent size %" PRIu32 " is not a power of two", + s->extent_size); + ret = -EINVAL; + goto fail; + } else if (s->extent_size > 0x800000) { + error_setg(errp, "Extent size %" PRIu32 " is too large", + s->extent_size); + ret = -EINVAL; + goto fail; + } + + if (s->catalog_size < DIV_ROUND_UP(bs->total_sectors, + s->extent_size / BDRV_SECTOR_SIZE)) + { + error_setg(errp, "Catalog size is too small for this disk size"); + ret = -EINVAL; + goto fail; + } + + qemu_co_mutex_init(&s->lock); + return 0; + +fail: + g_free(s->catalog_bitmap); + return ret; +} + +static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num) +{ + BDRVBochsState *s = bs->opaque; + uint64_t offset = sector_num * 512; + uint64_t extent_index, extent_offset, bitmap_offset; + char bitmap_entry; + int ret; + + // seek to sector + extent_index = offset / s->extent_size; + extent_offset = (offset % s->extent_size) / 512; + + if (s->catalog_bitmap[extent_index] == 0xffffffff) { + return 0; /* not allocated */ + } + + bitmap_offset = s->data_offset + + (512 * (uint64_t) s->catalog_bitmap[extent_index] * + (s->extent_blocks + s->bitmap_blocks)); + + /* read in bitmap for current extent */ + ret = bdrv_pread(bs->file, bitmap_offset + (extent_offset / 8), + &bitmap_entry, 1); + if (ret < 0) { + return ret; + } + + if (!((bitmap_entry >> (extent_offset % 8)) & 1)) { + return 0; /* not allocated */ + } + + return bitmap_offset + (512 * (s->bitmap_blocks + extent_offset)); +} + +static int bochs_read(BlockDriverState *bs, int64_t sector_num, + uint8_t *buf, int nb_sectors) +{ + int ret; + + while (nb_sectors > 0) { + int64_t block_offset = seek_to_sector(bs, sector_num); + if (block_offset < 0) { + return block_offset; + } else if (block_offset > 0) { + ret = bdrv_pread(bs->file, block_offset, buf, 512); + if (ret < 0) { + return ret; + } + } else { + memset(buf, 0, 512); + } + nb_sectors--; + sector_num++; + buf += 512; + } + return 0; +} + +static coroutine_fn int bochs_co_read(BlockDriverState *bs, int64_t sector_num, + uint8_t *buf, int nb_sectors) +{ + int ret; + BDRVBochsState *s = bs->opaque; + qemu_co_mutex_lock(&s->lock); + ret = bochs_read(bs, sector_num, buf, nb_sectors); + qemu_co_mutex_unlock(&s->lock); + return ret; +} + +static void bochs_close(BlockDriverState *bs) +{ + BDRVBochsState *s = bs->opaque; + g_free(s->catalog_bitmap); +} + +static BlockDriver bdrv_bochs = { + .format_name = "bochs", + .instance_size = sizeof(BDRVBochsState), + .bdrv_probe = bochs_probe, + .bdrv_open = bochs_open, + .bdrv_read = bochs_co_read, + .bdrv_close = bochs_close, +}; + +static void bdrv_bochs_init(void) +{ + bdrv_register(&bdrv_bochs); +} + +block_init(bdrv_bochs_init); -- cgit 1.2.3-korg