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/*
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* Block driver for the VMDK format
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*
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* Copyright (c) 2004 Fabrice Bellard
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* Copyright (c) 2005 Filip Navara
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h" |
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#include "block_int.h" |
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|
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#define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D') |
30 |
#define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V') |
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|
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typedef struct { |
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uint32_t version; |
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uint32_t flags; |
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uint32_t disk_sectors; |
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uint32_t granularity; |
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uint32_t l1dir_offset; |
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uint32_t l1dir_size; |
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uint32_t file_sectors; |
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uint32_t cylinders; |
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uint32_t heads; |
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uint32_t sectors_per_track; |
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} VMDK3Header; |
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|
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typedef struct { |
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uint32_t version; |
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uint32_t flags; |
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int64_t capacity; |
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int64_t granularity; |
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int64_t desc_offset; |
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int64_t desc_size; |
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int32_t num_gtes_per_gte; |
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int64_t rgd_offset; |
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int64_t gd_offset; |
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int64_t grain_offset; |
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char filler[1]; |
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char check_bytes[4]; |
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} __attribute__((packed)) VMDK4Header; |
59 |
|
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#define L2_CACHE_SIZE 16 |
61 |
|
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typedef struct BDRVVmdkState { |
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BlockDriverState *hd; |
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int64_t l1_table_offset; |
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int64_t l1_backup_table_offset; |
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uint32_t *l1_table; |
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uint32_t *l1_backup_table; |
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unsigned int l1_size; |
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uint32_t l1_entry_sectors; |
70 |
|
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unsigned int l2_size; |
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uint32_t *l2_cache; |
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uint32_t l2_cache_offsets[L2_CACHE_SIZE]; |
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uint32_t l2_cache_counts[L2_CACHE_SIZE]; |
75 |
|
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unsigned int cluster_sectors; |
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uint32_t parent_cid; |
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int is_parent;
|
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} BDRVVmdkState; |
80 |
|
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typedef struct VmdkMetaData { |
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uint32_t offset; |
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unsigned int l1_index; |
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unsigned int l2_index; |
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unsigned int l2_offset; |
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int valid;
|
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} VmdkMetaData; |
88 |
|
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typedef struct ActiveBDRVState{ |
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BlockDriverState *hd; // active image handler
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uint64_t cluster_offset; // current write offset
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}ActiveBDRVState; |
93 |
|
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static ActiveBDRVState activeBDRV;
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|
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|
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static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename) |
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{ |
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uint32_t magic; |
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|
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if (buf_size < 4) |
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return 0; |
103 |
magic = be32_to_cpu(*(uint32_t *)buf); |
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if (magic == VMDK3_MAGIC ||
|
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magic == VMDK4_MAGIC) |
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return 100; |
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else
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return 0; |
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} |
110 |
|
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#define CHECK_CID 1 |
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|
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#define SECTOR_SIZE 512 |
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#define DESC_SIZE 20*SECTOR_SIZE // 20 sectors of 512 bytes each |
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#define HEADER_SIZE 512 // first sector of 512 bytes |
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|
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static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent) |
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{ |
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BDRVVmdkState *s = bs->opaque; |
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char desc[DESC_SIZE];
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uint32_t cid; |
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char *p_name, *cid_str;
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size_t cid_str_size; |
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|
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/* the descriptor offset = 0x200 */
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if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE) |
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return 0; |
128 |
|
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if (parent) {
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cid_str = "parentCID";
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cid_str_size = sizeof("parentCID"); |
132 |
} else {
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cid_str = "CID";
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cid_str_size = sizeof("CID"); |
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} |
136 |
|
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if ((p_name = strstr(desc,cid_str)) != 0) { |
138 |
p_name += cid_str_size; |
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sscanf(p_name,"%x",&cid);
|
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} |
141 |
|
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return cid;
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} |
144 |
|
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static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid) |
146 |
{ |
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BDRVVmdkState *s = bs->opaque; |
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char desc[DESC_SIZE], tmp_desc[DESC_SIZE];
|
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char *p_name, *tmp_str;
|
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|
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/* the descriptor offset = 0x200 */
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if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE) |
153 |
return -1; |
154 |
|
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tmp_str = strstr(desc,"parentCID");
|
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strcpy(tmp_desc, tmp_str); |
157 |
if ((p_name = strstr(desc,"CID")) != 0) { |
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p_name += sizeof("CID"); |
159 |
sprintf(p_name,"%x\n",cid);
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strcat(desc,tmp_desc); |
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} |
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|
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if (bdrv_pwrite(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE) |
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return -1; |
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return 0; |
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} |
167 |
|
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static int vmdk_is_cid_valid(BlockDriverState *bs) |
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{ |
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#ifdef CHECK_CID
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BDRVVmdkState *s = bs->opaque; |
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BlockDriverState *p_bs = s->hd->backing_hd; |
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uint32_t cur_pcid; |
174 |
|
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if (p_bs) {
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cur_pcid = vmdk_read_cid(p_bs,0);
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if (s->parent_cid != cur_pcid)
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// CID not valid
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return 0; |
180 |
} |
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#endif
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// CID valid
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return 1; |
184 |
} |
185 |
|
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static int vmdk_snapshot_create(const char *filename, const char *backing_file) |
187 |
{ |
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int snp_fd, p_fd;
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uint32_t p_cid; |
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char *p_name, *gd_buf, *rgd_buf;
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const char *real_filename, *temp_str; |
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VMDK4Header header; |
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uint32_t gde_entries, gd_size; |
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int64_t gd_offset, rgd_offset, capacity, gt_size; |
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char p_desc[DESC_SIZE], s_desc[DESC_SIZE], hdr[HEADER_SIZE];
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char *desc_template =
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"# Disk DescriptorFile\n"
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"version=1\n"
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"CID=%x\n"
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"parentCID=%x\n"
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"createType=\"monolithicSparse\"\n"
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"parentFileNameHint=\"%s\"\n"
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"\n"
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"# Extent description\n"
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"RW %lu SPARSE \"%s\"\n"
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"\n"
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"# The Disk Data Base \n"
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"#DDB\n"
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"\n";
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snp_fd = open(filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, 0644);
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if (snp_fd < 0) |
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return -1; |
214 |
p_fd = open(backing_file, O_RDONLY | O_BINARY | O_LARGEFILE); |
215 |
if (p_fd < 0) { |
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close(snp_fd); |
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return -1; |
218 |
} |
219 |
|
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/* read the header */
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if (lseek(p_fd, 0x0, SEEK_SET) == -1) |
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goto fail;
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if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE)
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goto fail;
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|
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/* write the header */
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if (lseek(snp_fd, 0x0, SEEK_SET) == -1) |
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goto fail;
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if (write(snp_fd, hdr, HEADER_SIZE) == -1) |
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goto fail;
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231 |
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memset(&header, 0, sizeof(header)); |
233 |
memcpy(&header,&hdr[4], sizeof(header)); // skip the VMDK4_MAGIC |
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|
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ftruncate(snp_fd, header.grain_offset << 9);
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/* the descriptor offset = 0x200 */
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if (lseek(p_fd, 0x200, SEEK_SET) == -1) |
238 |
goto fail;
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if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE)
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goto fail;
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241 |
|
242 |
if ((p_name = strstr(p_desc,"CID")) != 0) { |
243 |
p_name += sizeof("CID"); |
244 |
sscanf(p_name,"%x",&p_cid);
|
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} |
246 |
|
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real_filename = filename; |
248 |
if ((temp_str = strrchr(real_filename, '\\')) != NULL) |
249 |
real_filename = temp_str + 1;
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if ((temp_str = strrchr(real_filename, '/')) != NULL) |
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real_filename = temp_str + 1;
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if ((temp_str = strrchr(real_filename, ':')) != NULL) |
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real_filename = temp_str + 1;
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|
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sprintf(s_desc, desc_template, p_cid, p_cid, backing_file |
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, (uint32_t)header.capacity, real_filename); |
257 |
|
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/* write the descriptor */
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if (lseek(snp_fd, 0x200, SEEK_SET) == -1) |
260 |
goto fail;
|
261 |
if (write(snp_fd, s_desc, strlen(s_desc)) == -1) |
262 |
goto fail;
|
263 |
|
264 |
gd_offset = header.gd_offset * SECTOR_SIZE; // offset of GD table
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rgd_offset = header.rgd_offset * SECTOR_SIZE; // offset of RGD table
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capacity = header.capacity * SECTOR_SIZE; // Extent size
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/*
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* Each GDE span 32M disk, means:
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* 512 GTE per GT, each GTE points to grain
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270 |
*/
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gt_size = (int64_t)header.num_gtes_per_gte * header.granularity * SECTOR_SIZE; |
272 |
if (!gt_size)
|
273 |
goto fail;
|
274 |
gde_entries = (uint32_t)(capacity / gt_size); // number of gde/rgde
|
275 |
gd_size = gde_entries * sizeof(uint32_t);
|
276 |
|
277 |
/* write RGD */
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278 |
rgd_buf = qemu_malloc(gd_size); |
279 |
if (!rgd_buf)
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280 |
goto fail;
|
281 |
if (lseek(p_fd, rgd_offset, SEEK_SET) == -1) |
282 |
goto fail_rgd;
|
283 |
if (read(p_fd, rgd_buf, gd_size) != gd_size)
|
284 |
goto fail_rgd;
|
285 |
if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1) |
286 |
goto fail_rgd;
|
287 |
if (write(snp_fd, rgd_buf, gd_size) == -1) |
288 |
goto fail_rgd;
|
289 |
qemu_free(rgd_buf); |
290 |
|
291 |
/* write GD */
|
292 |
gd_buf = qemu_malloc(gd_size); |
293 |
if (!gd_buf)
|
294 |
goto fail_rgd;
|
295 |
if (lseek(p_fd, gd_offset, SEEK_SET) == -1) |
296 |
goto fail_gd;
|
297 |
if (read(p_fd, gd_buf, gd_size) != gd_size)
|
298 |
goto fail_gd;
|
299 |
if (lseek(snp_fd, gd_offset, SEEK_SET) == -1) |
300 |
goto fail_gd;
|
301 |
if (write(snp_fd, gd_buf, gd_size) == -1) |
302 |
goto fail_gd;
|
303 |
qemu_free(gd_buf); |
304 |
|
305 |
close(p_fd); |
306 |
close(snp_fd); |
307 |
return 0; |
308 |
|
309 |
fail_gd:
|
310 |
qemu_free(gd_buf); |
311 |
fail_rgd:
|
312 |
qemu_free(rgd_buf); |
313 |
fail:
|
314 |
close(p_fd); |
315 |
close(snp_fd); |
316 |
return -1; |
317 |
} |
318 |
|
319 |
static void vmdk_parent_close(BlockDriverState *bs) |
320 |
{ |
321 |
if (bs->backing_hd)
|
322 |
bdrv_close(bs->backing_hd); |
323 |
} |
324 |
|
325 |
int parent_open = 0; |
326 |
static int vmdk_parent_open(BlockDriverState *bs, const char * filename) |
327 |
{ |
328 |
BDRVVmdkState *s = bs->opaque; |
329 |
char *p_name;
|
330 |
char desc[DESC_SIZE];
|
331 |
char parent_img_name[1024]; |
332 |
|
333 |
/* the descriptor offset = 0x200 */
|
334 |
if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE) |
335 |
return -1; |
336 |
|
337 |
if ((p_name = strstr(desc,"parentFileNameHint")) != 0) { |
338 |
char *end_name;
|
339 |
struct stat file_buf;
|
340 |
|
341 |
p_name += sizeof("parentFileNameHint") + 1; |
342 |
if ((end_name = strchr(p_name,'\"')) == 0) |
343 |
return -1; |
344 |
if ((end_name - p_name) > sizeof (s->hd->backing_file) - 1) |
345 |
return -1; |
346 |
|
347 |
strncpy(s->hd->backing_file, p_name, end_name - p_name); |
348 |
if (stat(s->hd->backing_file, &file_buf) != 0) { |
349 |
path_combine(parent_img_name, sizeof(parent_img_name),
|
350 |
filename, s->hd->backing_file); |
351 |
} else {
|
352 |
strcpy(parent_img_name, s->hd->backing_file); |
353 |
} |
354 |
|
355 |
s->hd->backing_hd = bdrv_new("");
|
356 |
if (!s->hd->backing_hd) {
|
357 |
failure:
|
358 |
bdrv_close(s->hd); |
359 |
return -1; |
360 |
} |
361 |
parent_open = 1;
|
362 |
if (bdrv_open(s->hd->backing_hd, parent_img_name, BDRV_O_RDONLY) < 0) |
363 |
goto failure;
|
364 |
parent_open = 0;
|
365 |
} |
366 |
|
367 |
return 0; |
368 |
} |
369 |
|
370 |
static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) |
371 |
{ |
372 |
BDRVVmdkState *s = bs->opaque; |
373 |
uint32_t magic; |
374 |
int l1_size, i, ret;
|
375 |
|
376 |
if (parent_open)
|
377 |
// Parent must be opened as RO.
|
378 |
flags = BDRV_O_RDONLY; |
379 |
fprintf(stderr, "(VMDK) image open: flags=0x%x filename=%s\n", flags, bs->filename);
|
380 |
|
381 |
ret = bdrv_file_open(&s->hd, filename, flags); |
382 |
if (ret < 0) |
383 |
return ret;
|
384 |
if (bdrv_pread(s->hd, 0, &magic, sizeof(magic)) != sizeof(magic)) |
385 |
goto fail;
|
386 |
|
387 |
magic = be32_to_cpu(magic); |
388 |
if (magic == VMDK3_MAGIC) {
|
389 |
VMDK3Header header; |
390 |
|
391 |
if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header)) |
392 |
goto fail;
|
393 |
s->cluster_sectors = le32_to_cpu(header.granularity); |
394 |
s->l2_size = 1 << 9; |
395 |
s->l1_size = 1 << 6; |
396 |
bs->total_sectors = le32_to_cpu(header.disk_sectors); |
397 |
s->l1_table_offset = le32_to_cpu(header.l1dir_offset) << 9;
|
398 |
s->l1_backup_table_offset = 0;
|
399 |
s->l1_entry_sectors = s->l2_size * s->cluster_sectors; |
400 |
} else if (magic == VMDK4_MAGIC) { |
401 |
VMDK4Header header; |
402 |
|
403 |
if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header)) |
404 |
goto fail;
|
405 |
bs->total_sectors = le64_to_cpu(header.capacity); |
406 |
s->cluster_sectors = le64_to_cpu(header.granularity); |
407 |
s->l2_size = le32_to_cpu(header.num_gtes_per_gte); |
408 |
s->l1_entry_sectors = s->l2_size * s->cluster_sectors; |
409 |
if (s->l1_entry_sectors <= 0) |
410 |
goto fail;
|
411 |
s->l1_size = (bs->total_sectors + s->l1_entry_sectors - 1)
|
412 |
/ s->l1_entry_sectors; |
413 |
s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9;
|
414 |
s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
|
415 |
|
416 |
if (parent_open)
|
417 |
s->is_parent = 1;
|
418 |
else
|
419 |
s->is_parent = 0;
|
420 |
|
421 |
// try to open parent images, if exist
|
422 |
if (vmdk_parent_open(bs, filename) != 0) |
423 |
goto fail;
|
424 |
// write the CID once after the image creation
|
425 |
s->parent_cid = vmdk_read_cid(bs,1);
|
426 |
} else {
|
427 |
goto fail;
|
428 |
} |
429 |
|
430 |
/* read the L1 table */
|
431 |
l1_size = s->l1_size * sizeof(uint32_t);
|
432 |
s->l1_table = qemu_malloc(l1_size); |
433 |
if (!s->l1_table)
|
434 |
goto fail;
|
435 |
if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, l1_size) != l1_size)
|
436 |
goto fail;
|
437 |
for(i = 0; i < s->l1_size; i++) { |
438 |
le32_to_cpus(&s->l1_table[i]); |
439 |
} |
440 |
|
441 |
if (s->l1_backup_table_offset) {
|
442 |
s->l1_backup_table = qemu_malloc(l1_size); |
443 |
if (!s->l1_backup_table)
|
444 |
goto fail;
|
445 |
if (bdrv_pread(s->hd, s->l1_backup_table_offset, s->l1_backup_table, l1_size) != l1_size)
|
446 |
goto fail;
|
447 |
for(i = 0; i < s->l1_size; i++) { |
448 |
le32_to_cpus(&s->l1_backup_table[i]); |
449 |
} |
450 |
} |
451 |
|
452 |
s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint32_t));
|
453 |
if (!s->l2_cache)
|
454 |
goto fail;
|
455 |
return 0; |
456 |
fail:
|
457 |
qemu_free(s->l1_backup_table); |
458 |
qemu_free(s->l1_table); |
459 |
qemu_free(s->l2_cache); |
460 |
bdrv_delete(s->hd); |
461 |
return -1; |
462 |
} |
463 |
|
464 |
static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data,
|
465 |
uint64_t offset, int allocate);
|
466 |
|
467 |
static int get_whole_cluster(BlockDriverState *bs, uint64_t cluster_offset, |
468 |
uint64_t offset, int allocate)
|
469 |
{ |
470 |
uint64_t parent_cluster_offset; |
471 |
BDRVVmdkState *s = bs->opaque; |
472 |
uint8_t whole_grain[s->cluster_sectors*512]; // 128 sectors * 512 bytes each = grain size 64KB |
473 |
|
474 |
// we will be here if it's first write on non-exist grain(cluster).
|
475 |
// try to read from parent image, if exist
|
476 |
if (s->hd->backing_hd) {
|
477 |
BDRVVmdkState *ps = s->hd->backing_hd->opaque; |
478 |
|
479 |
if (!vmdk_is_cid_valid(bs))
|
480 |
return -1; |
481 |
|
482 |
parent_cluster_offset = get_cluster_offset(s->hd->backing_hd, NULL, offset, allocate);
|
483 |
|
484 |
if (parent_cluster_offset) {
|
485 |
BDRVVmdkState *act_s = activeBDRV.hd->opaque; |
486 |
|
487 |
if (bdrv_pread(ps->hd, parent_cluster_offset, whole_grain, ps->cluster_sectors*512) != ps->cluster_sectors*512) |
488 |
return -1; |
489 |
|
490 |
//Write grain only into the active image
|
491 |
if (bdrv_pwrite(act_s->hd, activeBDRV.cluster_offset << 9, whole_grain, sizeof(whole_grain)) != sizeof(whole_grain)) |
492 |
return -1; |
493 |
} |
494 |
} |
495 |
return 0; |
496 |
} |
497 |
|
498 |
static int vmdk_L2update(BlockDriverState *bs, VmdkMetaData *m_data) |
499 |
{ |
500 |
BDRVVmdkState *s = bs->opaque; |
501 |
|
502 |
/* update L2 table */
|
503 |
if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)), |
504 |
&(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset)) |
505 |
return -1; |
506 |
/* update backup L2 table */
|
507 |
if (s->l1_backup_table_offset != 0) { |
508 |
m_data->l2_offset = s->l1_backup_table[m_data->l1_index]; |
509 |
if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)), |
510 |
&(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset)) |
511 |
return -1; |
512 |
} |
513 |
|
514 |
return 0; |
515 |
} |
516 |
|
517 |
static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data,
|
518 |
uint64_t offset, int allocate)
|
519 |
{ |
520 |
BDRVVmdkState *s = bs->opaque; |
521 |
unsigned int l1_index, l2_offset, l2_index; |
522 |
int min_index, i, j;
|
523 |
uint32_t min_count, *l2_table, tmp = 0;
|
524 |
uint64_t cluster_offset; |
525 |
|
526 |
if (m_data)
|
527 |
m_data->valid = 0;
|
528 |
|
529 |
l1_index = (offset >> 9) / s->l1_entry_sectors;
|
530 |
if (l1_index >= s->l1_size)
|
531 |
return 0; |
532 |
l2_offset = s->l1_table[l1_index]; |
533 |
if (!l2_offset)
|
534 |
return 0; |
535 |
for(i = 0; i < L2_CACHE_SIZE; i++) { |
536 |
if (l2_offset == s->l2_cache_offsets[i]) {
|
537 |
/* increment the hit count */
|
538 |
if (++s->l2_cache_counts[i] == 0xffffffff) { |
539 |
for(j = 0; j < L2_CACHE_SIZE; j++) { |
540 |
s->l2_cache_counts[j] >>= 1;
|
541 |
} |
542 |
} |
543 |
l2_table = s->l2_cache + (i * s->l2_size); |
544 |
goto found;
|
545 |
} |
546 |
} |
547 |
/* not found: load a new entry in the least used one */
|
548 |
min_index = 0;
|
549 |
min_count = 0xffffffff;
|
550 |
for(i = 0; i < L2_CACHE_SIZE; i++) { |
551 |
if (s->l2_cache_counts[i] < min_count) {
|
552 |
min_count = s->l2_cache_counts[i]; |
553 |
min_index = i; |
554 |
} |
555 |
} |
556 |
l2_table = s->l2_cache + (min_index * s->l2_size); |
557 |
if (bdrv_pread(s->hd, (int64_t)l2_offset * 512, l2_table, s->l2_size * sizeof(uint32_t)) != |
558 |
s->l2_size * sizeof(uint32_t))
|
559 |
return 0; |
560 |
|
561 |
s->l2_cache_offsets[min_index] = l2_offset; |
562 |
s->l2_cache_counts[min_index] = 1;
|
563 |
found:
|
564 |
l2_index = ((offset >> 9) / s->cluster_sectors) % s->l2_size;
|
565 |
cluster_offset = le32_to_cpu(l2_table[l2_index]); |
566 |
|
567 |
if (!cluster_offset) {
|
568 |
if (!allocate)
|
569 |
return 0; |
570 |
// Avoid the L2 tables update for the images that have snapshots.
|
571 |
if (!s->is_parent) {
|
572 |
cluster_offset = bdrv_getlength(s->hd); |
573 |
bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9));
|
574 |
|
575 |
cluster_offset >>= 9;
|
576 |
tmp = cpu_to_le32(cluster_offset); |
577 |
l2_table[l2_index] = tmp; |
578 |
// Save the active image state
|
579 |
activeBDRV.cluster_offset = cluster_offset; |
580 |
activeBDRV.hd = bs; |
581 |
} |
582 |
/* First of all we write grain itself, to avoid race condition
|
583 |
* that may to corrupt the image.
|
584 |
* This problem may occur because of insufficient space on host disk
|
585 |
* or inappropriate VM shutdown.
|
586 |
*/
|
587 |
if (get_whole_cluster(bs, cluster_offset, offset, allocate) == -1) |
588 |
return 0; |
589 |
|
590 |
if (m_data) {
|
591 |
m_data->offset = tmp; |
592 |
m_data->l1_index = l1_index; |
593 |
m_data->l2_index = l2_index; |
594 |
m_data->l2_offset = l2_offset; |
595 |
m_data->valid = 1;
|
596 |
} |
597 |
} |
598 |
cluster_offset <<= 9;
|
599 |
return cluster_offset;
|
600 |
} |
601 |
|
602 |
static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num, |
603 |
int nb_sectors, int *pnum) |
604 |
{ |
605 |
BDRVVmdkState *s = bs->opaque; |
606 |
int index_in_cluster, n;
|
607 |
uint64_t cluster_offset; |
608 |
|
609 |
cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0); |
610 |
index_in_cluster = sector_num % s->cluster_sectors; |
611 |
n = s->cluster_sectors - index_in_cluster; |
612 |
if (n > nb_sectors)
|
613 |
n = nb_sectors; |
614 |
*pnum = n; |
615 |
return (cluster_offset != 0); |
616 |
} |
617 |
|
618 |
static int vmdk_read(BlockDriverState *bs, int64_t sector_num, |
619 |
uint8_t *buf, int nb_sectors)
|
620 |
{ |
621 |
BDRVVmdkState *s = bs->opaque; |
622 |
int index_in_cluster, n, ret;
|
623 |
uint64_t cluster_offset; |
624 |
|
625 |
while (nb_sectors > 0) { |
626 |
cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0); |
627 |
index_in_cluster = sector_num % s->cluster_sectors; |
628 |
n = s->cluster_sectors - index_in_cluster; |
629 |
if (n > nb_sectors)
|
630 |
n = nb_sectors; |
631 |
if (!cluster_offset) {
|
632 |
// try to read from parent image, if exist
|
633 |
if (s->hd->backing_hd) {
|
634 |
if (!vmdk_is_cid_valid(bs))
|
635 |
return -1; |
636 |
ret = bdrv_read(s->hd->backing_hd, sector_num, buf, n); |
637 |
if (ret < 0) |
638 |
return -1; |
639 |
} else {
|
640 |
memset(buf, 0, 512 * n); |
641 |
} |
642 |
} else {
|
643 |
if(bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512) |
644 |
return -1; |
645 |
} |
646 |
nb_sectors -= n; |
647 |
sector_num += n; |
648 |
buf += n * 512;
|
649 |
} |
650 |
return 0; |
651 |
} |
652 |
|
653 |
static int vmdk_write(BlockDriverState *bs, int64_t sector_num, |
654 |
const uint8_t *buf, int nb_sectors) |
655 |
{ |
656 |
BDRVVmdkState *s = bs->opaque; |
657 |
VmdkMetaData m_data; |
658 |
int index_in_cluster, n;
|
659 |
uint64_t cluster_offset; |
660 |
static int cid_update = 0; |
661 |
|
662 |
if (sector_num > bs->total_sectors) {
|
663 |
fprintf(stderr, |
664 |
"(VMDK) Wrong offset: sector_num=0x%" PRIx64
|
665 |
" total_sectors=0x%" PRIx64 "\n", |
666 |
sector_num, bs->total_sectors); |
667 |
return -1; |
668 |
} |
669 |
|
670 |
while (nb_sectors > 0) { |
671 |
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
672 |
n = s->cluster_sectors - index_in_cluster; |
673 |
if (n > nb_sectors)
|
674 |
n = nb_sectors; |
675 |
cluster_offset = get_cluster_offset(bs, &m_data, sector_num << 9, 1); |
676 |
if (!cluster_offset)
|
677 |
return -1; |
678 |
|
679 |
if (bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512) |
680 |
return -1; |
681 |
if (m_data.valid) {
|
682 |
/* update L2 tables */
|
683 |
if (vmdk_L2update(bs, &m_data) == -1) |
684 |
return -1; |
685 |
} |
686 |
nb_sectors -= n; |
687 |
sector_num += n; |
688 |
buf += n * 512;
|
689 |
|
690 |
// update CID on the first write every time the virtual disk is opened
|
691 |
if (!cid_update) {
|
692 |
vmdk_write_cid(bs, time(NULL));
|
693 |
cid_update++; |
694 |
} |
695 |
} |
696 |
return 0; |
697 |
} |
698 |
|
699 |
static int vmdk_create(const char *filename, int64_t total_size, |
700 |
const char *backing_file, int flags) |
701 |
{ |
702 |
int fd, i;
|
703 |
VMDK4Header header; |
704 |
uint32_t tmp, magic, grains, gd_size, gt_size, gt_count; |
705 |
char *desc_template =
|
706 |
"# Disk DescriptorFile\n"
|
707 |
"version=1\n"
|
708 |
"CID=%x\n"
|
709 |
"parentCID=ffffffff\n"
|
710 |
"createType=\"monolithicSparse\"\n"
|
711 |
"\n"
|
712 |
"# Extent description\n"
|
713 |
"RW %lu SPARSE \"%s\"\n"
|
714 |
"\n"
|
715 |
"# The Disk Data Base \n"
|
716 |
"#DDB\n"
|
717 |
"\n"
|
718 |
"ddb.virtualHWVersion = \"%d\"\n"
|
719 |
"ddb.geometry.cylinders = \"%lu\"\n"
|
720 |
"ddb.geometry.heads = \"16\"\n"
|
721 |
"ddb.geometry.sectors = \"63\"\n"
|
722 |
"ddb.adapterType = \"ide\"\n";
|
723 |
char desc[1024]; |
724 |
const char *real_filename, *temp_str; |
725 |
|
726 |
/* XXX: add support for backing file */
|
727 |
if (backing_file) {
|
728 |
return vmdk_snapshot_create(filename, backing_file);
|
729 |
} |
730 |
|
731 |
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, |
732 |
0644);
|
733 |
if (fd < 0) |
734 |
return -1; |
735 |
magic = cpu_to_be32(VMDK4_MAGIC); |
736 |
memset(&header, 0, sizeof(header)); |
737 |
header.version = cpu_to_le32(1);
|
738 |
header.flags = cpu_to_le32(3); /* ?? */ |
739 |
header.capacity = cpu_to_le64(total_size); |
740 |
header.granularity = cpu_to_le64(128);
|
741 |
header.num_gtes_per_gte = cpu_to_le32(512);
|
742 |
|
743 |
grains = (total_size + header.granularity - 1) / header.granularity;
|
744 |
gt_size = ((header.num_gtes_per_gte * sizeof(uint32_t)) + 511) >> 9; |
745 |
gt_count = (grains + header.num_gtes_per_gte - 1) / header.num_gtes_per_gte;
|
746 |
gd_size = (gt_count * sizeof(uint32_t) + 511) >> 9; |
747 |
|
748 |
header.desc_offset = 1;
|
749 |
header.desc_size = 20;
|
750 |
header.rgd_offset = header.desc_offset + header.desc_size; |
751 |
header.gd_offset = header.rgd_offset + gd_size + (gt_size * gt_count); |
752 |
header.grain_offset = |
753 |
((header.gd_offset + gd_size + (gt_size * gt_count) + |
754 |
header.granularity - 1) / header.granularity) *
|
755 |
header.granularity; |
756 |
|
757 |
header.desc_offset = cpu_to_le64(header.desc_offset); |
758 |
header.desc_size = cpu_to_le64(header.desc_size); |
759 |
header.rgd_offset = cpu_to_le64(header.rgd_offset); |
760 |
header.gd_offset = cpu_to_le64(header.gd_offset); |
761 |
header.grain_offset = cpu_to_le64(header.grain_offset); |
762 |
|
763 |
header.check_bytes[0] = 0xa; |
764 |
header.check_bytes[1] = 0x20; |
765 |
header.check_bytes[2] = 0xd; |
766 |
header.check_bytes[3] = 0xa; |
767 |
|
768 |
/* write all the data */
|
769 |
write(fd, &magic, sizeof(magic));
|
770 |
write(fd, &header, sizeof(header));
|
771 |
|
772 |
ftruncate(fd, header.grain_offset << 9);
|
773 |
|
774 |
/* write grain directory */
|
775 |
lseek(fd, le64_to_cpu(header.rgd_offset) << 9, SEEK_SET);
|
776 |
for (i = 0, tmp = header.rgd_offset + gd_size; |
777 |
i < gt_count; i++, tmp += gt_size) |
778 |
write(fd, &tmp, sizeof(tmp));
|
779 |
|
780 |
/* write backup grain directory */
|
781 |
lseek(fd, le64_to_cpu(header.gd_offset) << 9, SEEK_SET);
|
782 |
for (i = 0, tmp = header.gd_offset + gd_size; |
783 |
i < gt_count; i++, tmp += gt_size) |
784 |
write(fd, &tmp, sizeof(tmp));
|
785 |
|
786 |
/* compose the descriptor */
|
787 |
real_filename = filename; |
788 |
if ((temp_str = strrchr(real_filename, '\\')) != NULL) |
789 |
real_filename = temp_str + 1;
|
790 |
if ((temp_str = strrchr(real_filename, '/')) != NULL) |
791 |
real_filename = temp_str + 1;
|
792 |
if ((temp_str = strrchr(real_filename, ':')) != NULL) |
793 |
real_filename = temp_str + 1;
|
794 |
sprintf(desc, desc_template, time(NULL), (unsigned long)total_size, |
795 |
real_filename, (flags & BLOCK_FLAG_COMPAT6 ? 6 : 4), total_size / (63 * 16)); |
796 |
|
797 |
/* write the descriptor */
|
798 |
lseek(fd, le64_to_cpu(header.desc_offset) << 9, SEEK_SET);
|
799 |
write(fd, desc, strlen(desc)); |
800 |
|
801 |
close(fd); |
802 |
return 0; |
803 |
} |
804 |
|
805 |
static void vmdk_close(BlockDriverState *bs) |
806 |
{ |
807 |
BDRVVmdkState *s = bs->opaque; |
808 |
|
809 |
qemu_free(s->l1_table); |
810 |
qemu_free(s->l2_cache); |
811 |
bdrv_delete(s->hd); |
812 |
// try to close parent image, if exist
|
813 |
vmdk_parent_close(s->hd); |
814 |
} |
815 |
|
816 |
static void vmdk_flush(BlockDriverState *bs) |
817 |
{ |
818 |
BDRVVmdkState *s = bs->opaque; |
819 |
bdrv_flush(s->hd); |
820 |
} |
821 |
|
822 |
BlockDriver bdrv_vmdk = { |
823 |
"vmdk",
|
824 |
sizeof(BDRVVmdkState),
|
825 |
vmdk_probe, |
826 |
vmdk_open, |
827 |
vmdk_read, |
828 |
vmdk_write, |
829 |
vmdk_close, |
830 |
vmdk_create, |
831 |
vmdk_flush, |
832 |
vmdk_is_allocated, |
833 |
}; |