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-rw-r--r--qemu/block/dmg.c725
1 files changed, 725 insertions, 0 deletions
diff --git a/qemu/block/dmg.c b/qemu/block/dmg.c
new file mode 100644
index 000000000..9f2528169
--- /dev/null
+++ b/qemu/block/dmg.c
@@ -0,0 +1,725 @@
+/*
+ * QEMU Block driver for DMG images
+ *
+ * Copyright (c) 2004 Johannes E. Schindelin
+ *
+ * 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/bswap.h"
+#include "qemu/error-report.h"
+#include "qemu/module.h"
+#include <zlib.h>
+#ifdef CONFIG_BZIP2
+#include <bzlib.h>
+#endif
+#include <glib.h>
+
+enum {
+ /* Limit chunk sizes to prevent unreasonable amounts of memory being used
+ * or truncating when converting to 32-bit types
+ */
+ DMG_LENGTHS_MAX = 64 * 1024 * 1024, /* 64 MB */
+ DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512,
+};
+
+typedef struct BDRVDMGState {
+ CoMutex lock;
+ /* each chunk contains a certain number of sectors,
+ * offsets[i] is the offset in the .dmg file,
+ * lengths[i] is the length of the compressed chunk,
+ * sectors[i] is the sector beginning at offsets[i],
+ * sectorcounts[i] is the number of sectors in that chunk,
+ * the sectors array is ordered
+ * 0<=i<n_chunks */
+
+ uint32_t n_chunks;
+ uint32_t* types;
+ uint64_t* offsets;
+ uint64_t* lengths;
+ uint64_t* sectors;
+ uint64_t* sectorcounts;
+ uint32_t current_chunk;
+ uint8_t *compressed_chunk;
+ uint8_t *uncompressed_chunk;
+ z_stream zstream;
+#ifdef CONFIG_BZIP2
+ bz_stream bzstream;
+#endif
+} BDRVDMGState;
+
+static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename)
+{
+ int len;
+
+ if (!filename) {
+ return 0;
+ }
+
+ len = strlen(filename);
+ if (len > 4 && !strcmp(filename + len - 4, ".dmg")) {
+ return 2;
+ }
+ return 0;
+}
+
+static int read_uint64(BlockDriverState *bs, int64_t offset, uint64_t *result)
+{
+ uint64_t buffer;
+ int ret;
+
+ ret = bdrv_pread(bs->file, offset, &buffer, 8);
+ if (ret < 0) {
+ return ret;
+ }
+
+ *result = be64_to_cpu(buffer);
+ return 0;
+}
+
+static int read_uint32(BlockDriverState *bs, int64_t offset, uint32_t *result)
+{
+ uint32_t buffer;
+ int ret;
+
+ ret = bdrv_pread(bs->file, offset, &buffer, 4);
+ if (ret < 0) {
+ return ret;
+ }
+
+ *result = be32_to_cpu(buffer);
+ return 0;
+}
+
+static inline uint64_t buff_read_uint64(const uint8_t *buffer, int64_t offset)
+{
+ return be64_to_cpu(*(uint64_t *)&buffer[offset]);
+}
+
+static inline uint32_t buff_read_uint32(const uint8_t *buffer, int64_t offset)
+{
+ return be32_to_cpu(*(uint32_t *)&buffer[offset]);
+}
+
+/* Increase max chunk sizes, if necessary. This function is used to calculate
+ * the buffer sizes needed for compressed/uncompressed chunk I/O.
+ */
+static void update_max_chunk_size(BDRVDMGState *s, uint32_t chunk,
+ uint32_t *max_compressed_size,
+ uint32_t *max_sectors_per_chunk)
+{
+ uint32_t compressed_size = 0;
+ uint32_t uncompressed_sectors = 0;
+
+ switch (s->types[chunk]) {
+ case 0x80000005: /* zlib compressed */
+ case 0x80000006: /* bzip2 compressed */
+ compressed_size = s->lengths[chunk];
+ uncompressed_sectors = s->sectorcounts[chunk];
+ break;
+ case 1: /* copy */
+ uncompressed_sectors = (s->lengths[chunk] + 511) / 512;
+ break;
+ case 2: /* zero */
+ /* as the all-zeroes block may be large, it is treated specially: the
+ * sector is not copied from a large buffer, a simple memset is used
+ * instead. Therefore uncompressed_sectors does not need to be set. */
+ break;
+ }
+
+ if (compressed_size > *max_compressed_size) {
+ *max_compressed_size = compressed_size;
+ }
+ if (uncompressed_sectors > *max_sectors_per_chunk) {
+ *max_sectors_per_chunk = uncompressed_sectors;
+ }
+}
+
+static int64_t dmg_find_koly_offset(BlockDriverState *file_bs, Error **errp)
+{
+ int64_t length;
+ int64_t offset = 0;
+ uint8_t buffer[515];
+ int i, ret;
+
+ /* bdrv_getlength returns a multiple of block size (512), rounded up. Since
+ * dmg images can have odd sizes, try to look for the "koly" magic which
+ * marks the begin of the UDIF trailer (512 bytes). This magic can be found
+ * in the last 511 bytes of the second-last sector or the first 4 bytes of
+ * the last sector (search space: 515 bytes) */
+ length = bdrv_getlength(file_bs);
+ if (length < 0) {
+ error_setg_errno(errp, -length,
+ "Failed to get file size while reading UDIF trailer");
+ return length;
+ } else if (length < 512) {
+ error_setg(errp, "dmg file must be at least 512 bytes long");
+ return -EINVAL;
+ }
+ if (length > 511 + 512) {
+ offset = length - 511 - 512;
+ }
+ length = length < 515 ? length : 515;
+ ret = bdrv_pread(file_bs, offset, buffer, length);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "Failed while reading UDIF trailer");
+ return ret;
+ }
+ for (i = 0; i < length - 3; i++) {
+ if (buffer[i] == 'k' && buffer[i+1] == 'o' &&
+ buffer[i+2] == 'l' && buffer[i+3] == 'y') {
+ return offset + i;
+ }
+ }
+ error_setg(errp, "Could not locate UDIF trailer in dmg file");
+ return -EINVAL;
+}
+
+/* used when building the sector table */
+typedef struct DmgHeaderState {
+ /* used internally by dmg_read_mish_block to remember offsets of blocks
+ * across calls */
+ uint64_t data_fork_offset;
+ /* exported for dmg_open */
+ uint32_t max_compressed_size;
+ uint32_t max_sectors_per_chunk;
+} DmgHeaderState;
+
+static bool dmg_is_known_block_type(uint32_t entry_type)
+{
+ switch (entry_type) {
+ case 0x00000001: /* uncompressed */
+ case 0x00000002: /* zeroes */
+ case 0x80000005: /* zlib */
+#ifdef CONFIG_BZIP2
+ case 0x80000006: /* bzip2 */
+#endif
+ return true;
+ default:
+ return false;
+ }
+}
+
+static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds,
+ uint8_t *buffer, uint32_t count)
+{
+ uint32_t type, i;
+ int ret;
+ size_t new_size;
+ uint32_t chunk_count;
+ int64_t offset = 0;
+ uint64_t data_offset;
+ uint64_t in_offset = ds->data_fork_offset;
+ uint64_t out_offset;
+
+ type = buff_read_uint32(buffer, offset);
+ /* skip data that is not a valid MISH block (invalid magic or too small) */
+ if (type != 0x6d697368 || count < 244) {
+ /* assume success for now */
+ return 0;
+ }
+
+ /* chunk offsets are relative to this sector number */
+ out_offset = buff_read_uint64(buffer, offset + 8);
+
+ /* location in data fork for (compressed) blob (in bytes) */
+ data_offset = buff_read_uint64(buffer, offset + 0x18);
+ in_offset += data_offset;
+
+ /* move to begin of chunk entries */
+ offset += 204;
+
+ chunk_count = (count - 204) / 40;
+ new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
+ s->types = g_realloc(s->types, new_size / 2);
+ s->offsets = g_realloc(s->offsets, new_size);
+ s->lengths = g_realloc(s->lengths, new_size);
+ s->sectors = g_realloc(s->sectors, new_size);
+ s->sectorcounts = g_realloc(s->sectorcounts, new_size);
+
+ for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
+ s->types[i] = buff_read_uint32(buffer, offset);
+ if (!dmg_is_known_block_type(s->types[i])) {
+ chunk_count--;
+ i--;
+ offset += 40;
+ continue;
+ }
+
+ /* sector number */
+ s->sectors[i] = buff_read_uint64(buffer, offset + 8);
+ s->sectors[i] += out_offset;
+
+ /* sector count */
+ s->sectorcounts[i] = buff_read_uint64(buffer, offset + 0x10);
+
+ /* all-zeroes sector (type 2) does not need to be "uncompressed" and can
+ * therefore be unbounded. */
+ if (s->types[i] != 2 && s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) {
+ error_report("sector count %" PRIu64 " for chunk %" PRIu32
+ " is larger than max (%u)",
+ s->sectorcounts[i], i, DMG_SECTORCOUNTS_MAX);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ /* offset in (compressed) data fork */
+ s->offsets[i] = buff_read_uint64(buffer, offset + 0x18);
+ s->offsets[i] += in_offset;
+
+ /* length in (compressed) data fork */
+ s->lengths[i] = buff_read_uint64(buffer, offset + 0x20);
+
+ if (s->lengths[i] > DMG_LENGTHS_MAX) {
+ error_report("length %" PRIu64 " for chunk %" PRIu32
+ " is larger than max (%u)",
+ s->lengths[i], i, DMG_LENGTHS_MAX);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ update_max_chunk_size(s, i, &ds->max_compressed_size,
+ &ds->max_sectors_per_chunk);
+ offset += 40;
+ }
+ s->n_chunks += chunk_count;
+ return 0;
+
+fail:
+ return ret;
+}
+
+static int dmg_read_resource_fork(BlockDriverState *bs, DmgHeaderState *ds,
+ uint64_t info_begin, uint64_t info_length)
+{
+ BDRVDMGState *s = bs->opaque;
+ int ret;
+ uint32_t count, rsrc_data_offset;
+ uint8_t *buffer = NULL;
+ uint64_t info_end;
+ uint64_t offset;
+
+ /* read offset from begin of resource fork (info_begin) to resource data */
+ ret = read_uint32(bs, info_begin, &rsrc_data_offset);
+ if (ret < 0) {
+ goto fail;
+ } else if (rsrc_data_offset > info_length) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ /* read length of resource data */
+ ret = read_uint32(bs, info_begin + 8, &count);
+ if (ret < 0) {
+ goto fail;
+ } else if (count == 0 || rsrc_data_offset + count > info_length) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ /* begin of resource data (consisting of one or more resources) */
+ offset = info_begin + rsrc_data_offset;
+
+ /* end of resource data (there is possibly a following resource map
+ * which will be ignored). */
+ info_end = offset + count;
+
+ /* read offsets (mish blocks) from one or more resources in resource data */
+ while (offset < info_end) {
+ /* size of following resource */
+ ret = read_uint32(bs, offset, &count);
+ if (ret < 0) {
+ goto fail;
+ } else if (count == 0 || count > info_end - offset) {
+ ret = -EINVAL;
+ goto fail;
+ }
+ offset += 4;
+
+ buffer = g_realloc(buffer, count);
+ ret = bdrv_pread(bs->file, offset, buffer, count);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ ret = dmg_read_mish_block(s, ds, buffer, count);
+ if (ret < 0) {
+ goto fail;
+ }
+ /* advance offset by size of resource */
+ offset += count;
+ }
+ ret = 0;
+
+fail:
+ g_free(buffer);
+ return ret;
+}
+
+static int dmg_read_plist_xml(BlockDriverState *bs, DmgHeaderState *ds,
+ uint64_t info_begin, uint64_t info_length)
+{
+ BDRVDMGState *s = bs->opaque;
+ int ret;
+ uint8_t *buffer = NULL;
+ char *data_begin, *data_end;
+
+ /* Have at least some length to avoid NULL for g_malloc. Attempt to set a
+ * safe upper cap on the data length. A test sample had a XML length of
+ * about 1 MiB. */
+ if (info_length == 0 || info_length > 16 * 1024 * 1024) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ buffer = g_malloc(info_length + 1);
+ buffer[info_length] = '\0';
+ ret = bdrv_pread(bs->file, info_begin, buffer, info_length);
+ if (ret != info_length) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ /* look for <data>...</data>. The data is 284 (0x11c) bytes after base64
+ * decode. The actual data element has 431 (0x1af) bytes which includes tabs
+ * and line feeds. */
+ data_end = (char *)buffer;
+ while ((data_begin = strstr(data_end, "<data>")) != NULL) {
+ guchar *mish;
+ gsize out_len = 0;
+
+ data_begin += 6;
+ data_end = strstr(data_begin, "</data>");
+ /* malformed XML? */
+ if (data_end == NULL) {
+ ret = -EINVAL;
+ goto fail;
+ }
+ *data_end++ = '\0';
+ mish = g_base64_decode(data_begin, &out_len);
+ ret = dmg_read_mish_block(s, ds, mish, (uint32_t)out_len);
+ g_free(mish);
+ if (ret < 0) {
+ goto fail;
+ }
+ }
+ ret = 0;
+
+fail:
+ g_free(buffer);
+ return ret;
+}
+
+static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ BDRVDMGState *s = bs->opaque;
+ DmgHeaderState ds;
+ uint64_t rsrc_fork_offset, rsrc_fork_length;
+ uint64_t plist_xml_offset, plist_xml_length;
+ int64_t offset;
+ int ret;
+
+ bs->read_only = 1;
+ s->n_chunks = 0;
+ s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
+ /* used by dmg_read_mish_block to keep track of the current I/O position */
+ ds.data_fork_offset = 0;
+ ds.max_compressed_size = 1;
+ ds.max_sectors_per_chunk = 1;
+
+ /* locate the UDIF trailer */
+ offset = dmg_find_koly_offset(bs->file, errp);
+ if (offset < 0) {
+ ret = offset;
+ goto fail;
+ }
+
+ /* offset of data fork (DataForkOffset) */
+ ret = read_uint64(bs, offset + 0x18, &ds.data_fork_offset);
+ if (ret < 0) {
+ goto fail;
+ } else if (ds.data_fork_offset > offset) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ /* offset of resource fork (RsrcForkOffset) */
+ ret = read_uint64(bs, offset + 0x28, &rsrc_fork_offset);
+ if (ret < 0) {
+ goto fail;
+ }
+ ret = read_uint64(bs, offset + 0x30, &rsrc_fork_length);
+ if (ret < 0) {
+ goto fail;
+ }
+ if (rsrc_fork_offset >= offset ||
+ rsrc_fork_length > offset - rsrc_fork_offset) {
+ ret = -EINVAL;
+ goto fail;
+ }
+ /* offset of property list (XMLOffset) */
+ ret = read_uint64(bs, offset + 0xd8, &plist_xml_offset);
+ if (ret < 0) {
+ goto fail;
+ }
+ ret = read_uint64(bs, offset + 0xe0, &plist_xml_length);
+ if (ret < 0) {
+ goto fail;
+ }
+ if (plist_xml_offset >= offset ||
+ plist_xml_length > offset - plist_xml_offset) {
+ ret = -EINVAL;
+ goto fail;
+ }
+ ret = read_uint64(bs, offset + 0x1ec, (uint64_t *)&bs->total_sectors);
+ if (ret < 0) {
+ goto fail;
+ }
+ if (bs->total_sectors < 0) {
+ ret = -EINVAL;
+ goto fail;
+ }
+ if (rsrc_fork_length != 0) {
+ ret = dmg_read_resource_fork(bs, &ds,
+ rsrc_fork_offset, rsrc_fork_length);
+ if (ret < 0) {
+ goto fail;
+ }
+ } else if (plist_xml_length != 0) {
+ ret = dmg_read_plist_xml(bs, &ds, plist_xml_offset, plist_xml_length);
+ if (ret < 0) {
+ goto fail;
+ }
+ } else {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ /* initialize zlib engine */
+ s->compressed_chunk = qemu_try_blockalign(bs->file,
+ ds.max_compressed_size + 1);
+ s->uncompressed_chunk = qemu_try_blockalign(bs->file,
+ 512 * ds.max_sectors_per_chunk);
+ if (s->compressed_chunk == NULL || s->uncompressed_chunk == NULL) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ if (inflateInit(&s->zstream) != Z_OK) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ s->current_chunk = s->n_chunks;
+
+ qemu_co_mutex_init(&s->lock);
+ return 0;
+
+fail:
+ g_free(s->types);
+ g_free(s->offsets);
+ g_free(s->lengths);
+ g_free(s->sectors);
+ g_free(s->sectorcounts);
+ qemu_vfree(s->compressed_chunk);
+ qemu_vfree(s->uncompressed_chunk);
+ return ret;
+}
+
+static inline int is_sector_in_chunk(BDRVDMGState* s,
+ uint32_t chunk_num, uint64_t sector_num)
+{
+ if (chunk_num >= s->n_chunks || s->sectors[chunk_num] > sector_num ||
+ s->sectors[chunk_num] + s->sectorcounts[chunk_num] <= sector_num) {
+ return 0;
+ } else {
+ return -1;
+ }
+}
+
+static inline uint32_t search_chunk(BDRVDMGState *s, uint64_t sector_num)
+{
+ /* binary search */
+ uint32_t chunk1 = 0, chunk2 = s->n_chunks, chunk3;
+ while (chunk1 != chunk2) {
+ chunk3 = (chunk1 + chunk2) / 2;
+ if (s->sectors[chunk3] > sector_num) {
+ chunk2 = chunk3;
+ } else if (s->sectors[chunk3] + s->sectorcounts[chunk3] > sector_num) {
+ return chunk3;
+ } else {
+ chunk1 = chunk3;
+ }
+ }
+ return s->n_chunks; /* error */
+}
+
+static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
+{
+ BDRVDMGState *s = bs->opaque;
+
+ if (!is_sector_in_chunk(s, s->current_chunk, sector_num)) {
+ int ret;
+ uint32_t chunk = search_chunk(s, sector_num);
+#ifdef CONFIG_BZIP2
+ uint64_t total_out;
+#endif
+
+ if (chunk >= s->n_chunks) {
+ return -1;
+ }
+
+ s->current_chunk = s->n_chunks;
+ switch (s->types[chunk]) { /* block entry type */
+ case 0x80000005: { /* zlib compressed */
+ /* we need to buffer, because only the chunk as whole can be
+ * inflated. */
+ ret = bdrv_pread(bs->file, s->offsets[chunk],
+ s->compressed_chunk, s->lengths[chunk]);
+ if (ret != s->lengths[chunk]) {
+ return -1;
+ }
+
+ s->zstream.next_in = s->compressed_chunk;
+ s->zstream.avail_in = s->lengths[chunk];
+ s->zstream.next_out = s->uncompressed_chunk;
+ s->zstream.avail_out = 512 * s->sectorcounts[chunk];
+ ret = inflateReset(&s->zstream);
+ if (ret != Z_OK) {
+ return -1;
+ }
+ ret = inflate(&s->zstream, Z_FINISH);
+ if (ret != Z_STREAM_END ||
+ s->zstream.total_out != 512 * s->sectorcounts[chunk]) {
+ return -1;
+ }
+ break; }
+#ifdef CONFIG_BZIP2
+ case 0x80000006: /* bzip2 compressed */
+ /* we need to buffer, because only the chunk as whole can be
+ * inflated. */
+ ret = bdrv_pread(bs->file, s->offsets[chunk],
+ s->compressed_chunk, s->lengths[chunk]);
+ if (ret != s->lengths[chunk]) {
+ return -1;
+ }
+
+ ret = BZ2_bzDecompressInit(&s->bzstream, 0, 0);
+ if (ret != BZ_OK) {
+ return -1;
+ }
+ s->bzstream.next_in = (char *)s->compressed_chunk;
+ s->bzstream.avail_in = (unsigned int) s->lengths[chunk];
+ s->bzstream.next_out = (char *)s->uncompressed_chunk;
+ s->bzstream.avail_out = (unsigned int) 512 * s->sectorcounts[chunk];
+ ret = BZ2_bzDecompress(&s->bzstream);
+ total_out = ((uint64_t)s->bzstream.total_out_hi32 << 32) +
+ s->bzstream.total_out_lo32;
+ BZ2_bzDecompressEnd(&s->bzstream);
+ if (ret != BZ_STREAM_END ||
+ total_out != 512 * s->sectorcounts[chunk]) {
+ return -1;
+ }
+ break;
+#endif /* CONFIG_BZIP2 */
+ case 1: /* copy */
+ ret = bdrv_pread(bs->file, s->offsets[chunk],
+ s->uncompressed_chunk, s->lengths[chunk]);
+ if (ret != s->lengths[chunk]) {
+ return -1;
+ }
+ break;
+ case 2: /* zero */
+ /* see dmg_read, it is treated specially. No buffer needs to be
+ * pre-filled, the zeroes can be set directly. */
+ break;
+ }
+ s->current_chunk = chunk;
+ }
+ return 0;
+}
+
+static int dmg_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ BDRVDMGState *s = bs->opaque;
+ int i;
+
+ for (i = 0; i < nb_sectors; i++) {
+ uint32_t sector_offset_in_chunk;
+ if (dmg_read_chunk(bs, sector_num + i) != 0) {
+ return -1;
+ }
+ /* Special case: current chunk is all zeroes. Do not perform a memcpy as
+ * s->uncompressed_chunk may be too small to cover the large all-zeroes
+ * section. dmg_read_chunk is called to find s->current_chunk */
+ if (s->types[s->current_chunk] == 2) { /* all zeroes block entry */
+ memset(buf + i * 512, 0, 512);
+ continue;
+ }
+ sector_offset_in_chunk = sector_num + i - s->sectors[s->current_chunk];
+ memcpy(buf + i * 512,
+ s->uncompressed_chunk + sector_offset_in_chunk * 512, 512);
+ }
+ return 0;
+}
+
+static coroutine_fn int dmg_co_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ int ret;
+ BDRVDMGState *s = bs->opaque;
+ qemu_co_mutex_lock(&s->lock);
+ ret = dmg_read(bs, sector_num, buf, nb_sectors);
+ qemu_co_mutex_unlock(&s->lock);
+ return ret;
+}
+
+static void dmg_close(BlockDriverState *bs)
+{
+ BDRVDMGState *s = bs->opaque;
+
+ g_free(s->types);
+ g_free(s->offsets);
+ g_free(s->lengths);
+ g_free(s->sectors);
+ g_free(s->sectorcounts);
+ qemu_vfree(s->compressed_chunk);
+ qemu_vfree(s->uncompressed_chunk);
+
+ inflateEnd(&s->zstream);
+}
+
+static BlockDriver bdrv_dmg = {
+ .format_name = "dmg",
+ .instance_size = sizeof(BDRVDMGState),
+ .bdrv_probe = dmg_probe,
+ .bdrv_open = dmg_open,
+ .bdrv_read = dmg_co_read,
+ .bdrv_close = dmg_close,
+};
+
+static void bdrv_dmg_init(void)
+{
+ bdrv_register(&bdrv_dmg);
+}
+
+block_init(bdrv_dmg_init);