Initial import of abandoned HQEMU version 2.5.2HEADmaster

1 files changed, 283 insertions, 0 deletions

diff --git a/src/block/cloop.c b/src/block/cloop.c
new file mode 100644
index 0000000..4190ae0
--- /dev/null
+++ b/src/block/cloop.c
@@ -0,0 +1,283 @@
+/*
+ * QEMU Block driver for CLOOP 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/module.h"
+#include <zlib.h>
+
+/* Maximum compressed block size */
+#define MAX_BLOCK_SIZE (64 * 1024 * 1024)
+
+typedef struct BDRVCloopState {
+    CoMutex lock;
+    uint32_t block_size;
+    uint32_t n_blocks;
+    uint64_t *offsets;
+    uint32_t sectors_per_block;
+    uint32_t current_block;
+    uint8_t *compressed_block;
+    uint8_t *uncompressed_block;
+    z_stream zstream;
+} BDRVCloopState;
+
+static int cloop_probe(const uint8_t *buf, int buf_size, const char *filename)
+{
+    const char *magic_version_2_0 = "#!/bin/sh\n"
+        "#V2.0 Format\n"
+        "modprobe cloop file=$0 && mount -r -t iso9660 /dev/cloop $1\n";
+    int length = strlen(magic_version_2_0);
+    if (length > buf_size) {
+        length = buf_size;
+    }
+    if (!memcmp(magic_version_2_0, buf, length)) {
+        return 2;
+    }
+    return 0;
+}
+
+static int cloop_open(BlockDriverState *bs, QDict *options, int flags,
+                      Error **errp)
+{
+    BDRVCloopState *s = bs->opaque;
+    uint32_t offsets_size, max_compressed_block_size = 1, i;
+    int ret;
+
+    bs->read_only = 1;
+
+    /* read header */
+    ret = bdrv_pread(bs->file->bs, 128, &s->block_size, 4);
+    if (ret < 0) {
+        return ret;
+    }
+    s->block_size = be32_to_cpu(s->block_size);
+    if (s->block_size % 512) {
+        error_setg(errp, "block_size %" PRIu32 " must be a multiple of 512",
+                   s->block_size);
+        return -EINVAL;
+    }
+    if (s->block_size == 0) {
+        error_setg(errp, "block_size cannot be zero");
+        return -EINVAL;
+    }
+
+    /* cloop's create_compressed_fs.c warns about block sizes beyond 256 KB but
+     * we can accept more.  Prevent ridiculous values like 4 GB - 1 since we
+     * need a buffer this big.
+     */
+    if (s->block_size > MAX_BLOCK_SIZE) {
+        error_setg(errp, "block_size %" PRIu32 " must be %u MB or less",
+                   s->block_size,
+                   MAX_BLOCK_SIZE / (1024 * 1024));
+        return -EINVAL;
+    }
+
+    ret = bdrv_pread(bs->file->bs, 128 + 4, &s->n_blocks, 4);
+    if (ret < 0) {
+        return ret;
+    }
+    s->n_blocks = be32_to_cpu(s->n_blocks);
+
+    /* read offsets */
+    if (s->n_blocks > (UINT32_MAX - 1) / sizeof(uint64_t)) {
+        /* Prevent integer overflow */
+        error_setg(errp, "n_blocks %" PRIu32 " must be %zu or less",
+                   s->n_blocks,
+                   (UINT32_MAX - 1) / sizeof(uint64_t));
+        return -EINVAL;
+    }
+    offsets_size = (s->n_blocks + 1) * sizeof(uint64_t);
+    if (offsets_size > 512 * 1024 * 1024) {
+        /* Prevent ridiculous offsets_size which causes memory allocation to
+         * fail or overflows bdrv_pread() size.  In practice the 512 MB
+         * offsets[] limit supports 16 TB images at 256 KB block size.
+         */
+        error_setg(errp, "image requires too many offsets, "
+                   "try increasing block size");
+        return -EINVAL;
+    }
+
+    s->offsets = g_try_malloc(offsets_size);
+    if (s->offsets == NULL) {
+        error_setg(errp, "Could not allocate offsets table");
+        return -ENOMEM;
+    }
+
+    ret = bdrv_pread(bs->file->bs, 128 + 4 + 4, s->offsets, offsets_size);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    for (i = 0; i < s->n_blocks + 1; i++) {
+        uint64_t size;
+
+        s->offsets[i] = be64_to_cpu(s->offsets[i]);
+        if (i == 0) {
+            continue;
+        }
+
+        if (s->offsets[i] < s->offsets[i - 1]) {
+            error_setg(errp, "offsets not monotonically increasing at "
+                       "index %" PRIu32 ", image file is corrupt", i);
+            ret = -EINVAL;
+            goto fail;
+        }
+
+        size = s->offsets[i] - s->offsets[i - 1];
+
+        /* Compressed blocks should be smaller than the uncompressed block size
+         * but maybe compression performed poorly so the compressed block is
+         * actually bigger.  Clamp down on unrealistic values to prevent
+         * ridiculous s->compressed_block allocation.
+         */
+        if (size > 2 * MAX_BLOCK_SIZE) {
+            error_setg(errp, "invalid compressed block size at index %" PRIu32
+                       ", image file is corrupt", i);
+            ret = -EINVAL;
+            goto fail;
+        }
+
+        if (size > max_compressed_block_size) {
+            max_compressed_block_size = size;
+        }
+    }
+
+    /* initialize zlib engine */
+    s->compressed_block = g_try_malloc(max_compressed_block_size + 1);
+    if (s->compressed_block == NULL) {
+        error_setg(errp, "Could not allocate compressed_block");
+        ret = -ENOMEM;
+        goto fail;
+    }
+
+    s->uncompressed_block = g_try_malloc(s->block_size);
+    if (s->uncompressed_block == NULL) {
+        error_setg(errp, "Could not allocate uncompressed_block");
+        ret = -ENOMEM;
+        goto fail;
+    }
+
+    if (inflateInit(&s->zstream) != Z_OK) {
+        ret = -EINVAL;
+        goto fail;
+    }
+    s->current_block = s->n_blocks;
+
+    s->sectors_per_block = s->block_size/512;
+    bs->total_sectors = s->n_blocks * s->sectors_per_block;
+    qemu_co_mutex_init(&s->lock);
+    return 0;
+
+fail:
+    g_free(s->offsets);
+    g_free(s->compressed_block);
+    g_free(s->uncompressed_block);
+    return ret;
+}
+
+static inline int cloop_read_block(BlockDriverState *bs, int block_num)
+{
+    BDRVCloopState *s = bs->opaque;
+
+    if (s->current_block != block_num) {
+        int ret;
+        uint32_t bytes = s->offsets[block_num + 1] - s->offsets[block_num];
+
+        ret = bdrv_pread(bs->file->bs, s->offsets[block_num],
+                         s->compressed_block, bytes);
+        if (ret != bytes) {
+            return -1;
+        }
+
+        s->zstream.next_in = s->compressed_block;
+        s->zstream.avail_in = bytes;
+        s->zstream.next_out = s->uncompressed_block;
+        s->zstream.avail_out = s->block_size;
+        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 != s->block_size) {
+            return -1;
+        }
+
+        s->current_block = block_num;
+    }
+    return 0;
+}
+
+static int cloop_read(BlockDriverState *bs, int64_t sector_num,
+                    uint8_t *buf, int nb_sectors)
+{
+    BDRVCloopState *s = bs->opaque;
+    int i;
+
+    for (i = 0; i < nb_sectors; i++) {
+        uint32_t sector_offset_in_block =
+            ((sector_num + i) % s->sectors_per_block),
+            block_num = (sector_num + i) / s->sectors_per_block;
+        if (cloop_read_block(bs, block_num) != 0) {
+            return -1;
+        }
+        memcpy(buf + i * 512,
+            s->uncompressed_block + sector_offset_in_block * 512, 512);
+    }
+    return 0;
+}
+
+static coroutine_fn int cloop_co_read(BlockDriverState *bs, int64_t sector_num,
+                                      uint8_t *buf, int nb_sectors)
+{
+    int ret;
+    BDRVCloopState *s = bs->opaque;
+    qemu_co_mutex_lock(&s->lock);
+    ret = cloop_read(bs, sector_num, buf, nb_sectors);
+    qemu_co_mutex_unlock(&s->lock);
+    return ret;
+}
+
+static void cloop_close(BlockDriverState *bs)
+{
+    BDRVCloopState *s = bs->opaque;
+    g_free(s->offsets);
+    g_free(s->compressed_block);
+    g_free(s->uncompressed_block);
+    inflateEnd(&s->zstream);
+}
+
+static BlockDriver bdrv_cloop = {
+    .format_name    = "cloop",
+    .instance_size  = sizeof(BDRVCloopState),
+    .bdrv_probe     = cloop_probe,
+    .bdrv_open      = cloop_open,
+    .bdrv_read      = cloop_co_read,
+    .bdrv_close     = cloop_close,
+};
+
+static void bdrv_cloop_init(void)
+{
+    bdrv_register(&bdrv_cloop);
+}
+
+block_init(bdrv_cloop_init);