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/*
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* Block driver for Connectix / Microsoft Virtual PC images
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*
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* Copyright (c) 2005 Alex Beregszaszi
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* Copyright (c) 2009 Kevin Wolf <kwolf@suse.de>
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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" |
26 |
#include "block/block_int.h" |
27 |
#include "qemu/module.h" |
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#include "migration/migration.h" |
29 |
#if defined(CONFIG_UUID)
|
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#include <uuid/uuid.h> |
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#endif
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|
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/**************************************************************/
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|
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#define HEADER_SIZE 512 |
36 |
|
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//#define CACHE
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|
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enum vhd_type {
|
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VHD_FIXED = 2,
|
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VHD_DYNAMIC = 3,
|
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VHD_DIFFERENCING = 4,
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}; |
44 |
|
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// Seconds since Jan 1, 2000 0:00:00 (UTC)
|
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#define VHD_TIMESTAMP_BASE 946684800 |
47 |
|
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// always big-endian
|
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typedef struct vhd_footer { |
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char creator[8]; // "conectix" |
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uint32_t features; |
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uint32_t version; |
53 |
|
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// Offset of next header structure, 0xFFFFFFFF if none
|
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uint64_t data_offset; |
56 |
|
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// Seconds since Jan 1, 2000 0:00:00 (UTC)
|
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uint32_t timestamp; |
59 |
|
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char creator_app[4]; // "vpc " |
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uint16_t major; |
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uint16_t minor; |
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char creator_os[4]; // "Wi2k" |
64 |
|
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uint64_t orig_size; |
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uint64_t size; |
67 |
|
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uint16_t cyls; |
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uint8_t heads; |
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uint8_t secs_per_cyl; |
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|
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uint32_t type; |
73 |
|
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// Checksum of the Hard Disk Footer ("one's complement of the sum of all
|
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// the bytes in the footer without the checksum field")
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uint32_t checksum; |
77 |
|
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// UUID used to identify a parent hard disk (backing file)
|
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uint8_t uuid[16];
|
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|
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uint8_t in_saved_state; |
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} QEMU_PACKED VHDFooter; |
83 |
|
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typedef struct vhd_dyndisk_header { |
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char magic[8]; // "cxsparse" |
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|
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// Offset of next header structure, 0xFFFFFFFF if none
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uint64_t data_offset; |
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|
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// Offset of the Block Allocation Table (BAT)
|
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uint64_t table_offset; |
92 |
|
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uint32_t version; |
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uint32_t max_table_entries; // 32bit/entry
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|
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// 2 MB by default, must be a power of two
|
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uint32_t block_size; |
98 |
|
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uint32_t checksum; |
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uint8_t parent_uuid[16];
|
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uint32_t parent_timestamp; |
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uint32_t reserved; |
103 |
|
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// Backing file name (in UTF-16)
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uint8_t parent_name[512];
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|
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struct {
|
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uint32_t platform; |
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uint32_t data_space; |
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uint32_t data_length; |
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uint32_t reserved; |
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uint64_t data_offset; |
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} parent_locator[8];
|
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} QEMU_PACKED VHDDynDiskHeader; |
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|
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typedef struct BDRVVPCState { |
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CoMutex lock; |
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uint8_t footer_buf[HEADER_SIZE]; |
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uint64_t free_data_block_offset; |
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int max_table_entries;
|
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uint32_t *pagetable; |
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uint64_t bat_offset; |
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uint64_t last_bitmap_offset; |
124 |
|
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uint32_t block_size; |
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uint32_t bitmap_size; |
127 |
|
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#ifdef CACHE
|
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uint8_t *pageentry_u8; |
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uint32_t *pageentry_u32; |
131 |
uint16_t *pageentry_u16; |
132 |
|
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uint64_t last_bitmap; |
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#endif
|
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|
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Error *migration_blocker; |
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} BDRVVPCState; |
138 |
|
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static uint32_t vpc_checksum(uint8_t* buf, size_t size)
|
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{ |
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uint32_t res = 0;
|
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int i;
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143 |
|
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for (i = 0; i < size; i++) |
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res += buf[i]; |
146 |
|
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return ~res;
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} |
149 |
|
150 |
|
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static int vpc_probe(const uint8_t *buf, int buf_size, const char *filename) |
152 |
{ |
153 |
if (buf_size >= 8 && !strncmp((char *)buf, "conectix", 8)) |
154 |
return 100; |
155 |
return 0; |
156 |
} |
157 |
|
158 |
static int vpc_open(BlockDriverState *bs, QDict *options, int flags, |
159 |
Error **errp) |
160 |
{ |
161 |
BDRVVPCState *s = bs->opaque; |
162 |
int i;
|
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VHDFooter *footer; |
164 |
VHDDynDiskHeader *dyndisk_header; |
165 |
uint8_t buf[HEADER_SIZE]; |
166 |
uint32_t checksum; |
167 |
int disk_type = VHD_DYNAMIC;
|
168 |
int ret;
|
169 |
|
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ret = bdrv_pread(bs->file, 0, s->footer_buf, HEADER_SIZE);
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if (ret < 0) { |
172 |
goto fail;
|
173 |
} |
174 |
|
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footer = (VHDFooter *) s->footer_buf; |
176 |
if (strncmp(footer->creator, "conectix", 8)) { |
177 |
int64_t offset = bdrv_getlength(bs->file); |
178 |
if (offset < 0) { |
179 |
ret = offset; |
180 |
goto fail;
|
181 |
} else if (offset < HEADER_SIZE) { |
182 |
ret = -EINVAL; |
183 |
goto fail;
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184 |
} |
185 |
|
186 |
/* If a fixed disk, the footer is found only at the end of the file */
|
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ret = bdrv_pread(bs->file, offset-HEADER_SIZE, s->footer_buf, |
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HEADER_SIZE); |
189 |
if (ret < 0) { |
190 |
goto fail;
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} |
192 |
if (strncmp(footer->creator, "conectix", 8)) { |
193 |
error_setg(errp, "invalid VPC image");
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ret = -EINVAL; |
195 |
goto fail;
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} |
197 |
disk_type = VHD_FIXED; |
198 |
} |
199 |
|
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checksum = be32_to_cpu(footer->checksum); |
201 |
footer->checksum = 0;
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if (vpc_checksum(s->footer_buf, HEADER_SIZE) != checksum)
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fprintf(stderr, "block-vpc: The header checksum of '%s' is "
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"incorrect.\n", bs->filename);
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205 |
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/* Write 'checksum' back to footer, or else will leave it with zero. */
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footer->checksum = be32_to_cpu(checksum); |
208 |
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// The visible size of a image in Virtual PC depends on the geometry
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// rather than on the size stored in the footer (the size in the footer
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// is too large usually)
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bs->total_sectors = (int64_t) |
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be16_to_cpu(footer->cyls) * footer->heads * footer->secs_per_cyl; |
214 |
|
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/* images created with disk2vhd report a far higher virtual size
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* than expected with the cyls * heads * sectors_per_cyl formula.
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* use the footer->size instead if the image was created with
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* disk2vhd.
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*/
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if (!strncmp(footer->creator_app, "d2v", 4)) { |
221 |
bs->total_sectors = be64_to_cpu(footer->size) / BDRV_SECTOR_SIZE; |
222 |
} |
223 |
|
224 |
/* Allow a maximum disk size of approximately 2 TB */
|
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if (bs->total_sectors >= 65535LL * 255 * 255) { |
226 |
ret = -EFBIG; |
227 |
goto fail;
|
228 |
} |
229 |
|
230 |
if (disk_type == VHD_DYNAMIC) {
|
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ret = bdrv_pread(bs->file, be64_to_cpu(footer->data_offset), buf, |
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HEADER_SIZE); |
233 |
if (ret < 0) { |
234 |
goto fail;
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} |
236 |
|
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dyndisk_header = (VHDDynDiskHeader *) buf; |
238 |
|
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if (strncmp(dyndisk_header->magic, "cxsparse", 8)) { |
240 |
ret = -EINVAL; |
241 |
goto fail;
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242 |
} |
243 |
|
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s->block_size = be32_to_cpu(dyndisk_header->block_size); |
245 |
s->bitmap_size = ((s->block_size / (8 * 512)) + 511) & ~511; |
246 |
|
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s->max_table_entries = be32_to_cpu(dyndisk_header->max_table_entries); |
248 |
s->pagetable = g_malloc(s->max_table_entries * 4);
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249 |
|
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s->bat_offset = be64_to_cpu(dyndisk_header->table_offset); |
251 |
|
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ret = bdrv_pread(bs->file, s->bat_offset, s->pagetable, |
253 |
s->max_table_entries * 4);
|
254 |
if (ret < 0) { |
255 |
goto fail;
|
256 |
} |
257 |
|
258 |
s->free_data_block_offset = |
259 |
(s->bat_offset + (s->max_table_entries * 4) + 511) & ~511; |
260 |
|
261 |
for (i = 0; i < s->max_table_entries; i++) { |
262 |
be32_to_cpus(&s->pagetable[i]); |
263 |
if (s->pagetable[i] != 0xFFFFFFFF) { |
264 |
int64_t next = (512 * (int64_t) s->pagetable[i]) +
|
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s->bitmap_size + s->block_size; |
266 |
|
267 |
if (next > s->free_data_block_offset) {
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s->free_data_block_offset = next; |
269 |
} |
270 |
} |
271 |
} |
272 |
|
273 |
if (s->free_data_block_offset > bdrv_getlength(bs->file)) {
|
274 |
error_setg(errp, "block-vpc: free_data_block_offset points after "
|
275 |
"the end of file. The image has been truncated.");
|
276 |
ret = -EINVAL; |
277 |
goto fail;
|
278 |
} |
279 |
|
280 |
s->last_bitmap_offset = (int64_t) -1;
|
281 |
|
282 |
#ifdef CACHE
|
283 |
s->pageentry_u8 = g_malloc(512);
|
284 |
s->pageentry_u32 = s->pageentry_u8; |
285 |
s->pageentry_u16 = s->pageentry_u8; |
286 |
s->last_pagetable = -1;
|
287 |
#endif
|
288 |
} |
289 |
|
290 |
qemu_co_mutex_init(&s->lock); |
291 |
|
292 |
/* Disable migration when VHD images are used */
|
293 |
error_set(&s->migration_blocker, |
294 |
QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED, |
295 |
"vpc", bs->device_name, "live migration"); |
296 |
migrate_add_blocker(s->migration_blocker); |
297 |
|
298 |
return 0; |
299 |
|
300 |
fail:
|
301 |
g_free(s->pagetable); |
302 |
#ifdef CACHE
|
303 |
g_free(s->pageentry_u8); |
304 |
#endif
|
305 |
return ret;
|
306 |
} |
307 |
|
308 |
static int vpc_reopen_prepare(BDRVReopenState *state, |
309 |
BlockReopenQueue *queue, Error **errp) |
310 |
{ |
311 |
return 0; |
312 |
} |
313 |
|
314 |
/*
|
315 |
* Returns the absolute byte offset of the given sector in the image file.
|
316 |
* If the sector is not allocated, -1 is returned instead.
|
317 |
*
|
318 |
* The parameter write must be 1 if the offset will be used for a write
|
319 |
* operation (the block bitmaps is updated then), 0 otherwise.
|
320 |
*/
|
321 |
static inline int64_t get_sector_offset(BlockDriverState *bs, |
322 |
int64_t sector_num, int write)
|
323 |
{ |
324 |
BDRVVPCState *s = bs->opaque; |
325 |
uint64_t offset = sector_num * 512;
|
326 |
uint64_t bitmap_offset, block_offset; |
327 |
uint32_t pagetable_index, pageentry_index; |
328 |
|
329 |
pagetable_index = offset / s->block_size; |
330 |
pageentry_index = (offset % s->block_size) / 512;
|
331 |
|
332 |
if (pagetable_index >= s->max_table_entries || s->pagetable[pagetable_index] == 0xffffffff) |
333 |
return -1; // not allocated |
334 |
|
335 |
bitmap_offset = 512 * (uint64_t) s->pagetable[pagetable_index];
|
336 |
block_offset = bitmap_offset + s->bitmap_size + (512 * pageentry_index);
|
337 |
|
338 |
// We must ensure that we don't write to any sectors which are marked as
|
339 |
// unused in the bitmap. We get away with setting all bits in the block
|
340 |
// bitmap each time we write to a new block. This might cause Virtual PC to
|
341 |
// miss sparse read optimization, but it's not a problem in terms of
|
342 |
// correctness.
|
343 |
if (write && (s->last_bitmap_offset != bitmap_offset)) {
|
344 |
uint8_t bitmap[s->bitmap_size]; |
345 |
|
346 |
s->last_bitmap_offset = bitmap_offset; |
347 |
memset(bitmap, 0xff, s->bitmap_size);
|
348 |
bdrv_pwrite_sync(bs->file, bitmap_offset, bitmap, s->bitmap_size); |
349 |
} |
350 |
|
351 |
// printf("sector: %" PRIx64 ", index: %x, offset: %x, bioff: %" PRIx64 ", bloff: %" PRIx64 "\n",
|
352 |
// sector_num, pagetable_index, pageentry_index,
|
353 |
// bitmap_offset, block_offset);
|
354 |
|
355 |
// disabled by reason
|
356 |
#if 0
|
357 |
#ifdef CACHE
|
358 |
if (bitmap_offset != s->last_bitmap)
|
359 |
{
|
360 |
lseek(s->fd, bitmap_offset, SEEK_SET);
|
361 |
|
362 |
s->last_bitmap = bitmap_offset;
|
363 |
|
364 |
// Scary! Bitmap is stored as big endian 32bit entries,
|
365 |
// while we used to look it up byte by byte
|
366 |
read(s->fd, s->pageentry_u8, 512);
|
367 |
for (i = 0; i < 128; i++)
|
368 |
be32_to_cpus(&s->pageentry_u32[i]);
|
369 |
}
|
370 |
|
371 |
if ((s->pageentry_u8[pageentry_index / 8] >> (pageentry_index % 8)) & 1)
|
372 |
return -1;
|
373 |
#else
|
374 |
lseek(s->fd, bitmap_offset + (pageentry_index / 8), SEEK_SET);
|
375 |
|
376 |
read(s->fd, &bitmap_entry, 1);
|
377 |
|
378 |
if ((bitmap_entry >> (pageentry_index % 8)) & 1) |
379 |
return -1; // not allocated |
380 |
#endif
|
381 |
#endif
|
382 |
|
383 |
return block_offset;
|
384 |
} |
385 |
|
386 |
/*
|
387 |
* Writes the footer to the end of the image file. This is needed when the
|
388 |
* file grows as it overwrites the old footer
|
389 |
*
|
390 |
* Returns 0 on success and < 0 on error
|
391 |
*/
|
392 |
static int rewrite_footer(BlockDriverState* bs) |
393 |
{ |
394 |
int ret;
|
395 |
BDRVVPCState *s = bs->opaque; |
396 |
int64_t offset = s->free_data_block_offset; |
397 |
|
398 |
ret = bdrv_pwrite_sync(bs->file, offset, s->footer_buf, HEADER_SIZE); |
399 |
if (ret < 0) |
400 |
return ret;
|
401 |
|
402 |
return 0; |
403 |
} |
404 |
|
405 |
/*
|
406 |
* Allocates a new block. This involves writing a new footer and updating
|
407 |
* the Block Allocation Table to use the space at the old end of the image
|
408 |
* file (overwriting the old footer)
|
409 |
*
|
410 |
* Returns the sectors' offset in the image file on success and < 0 on error
|
411 |
*/
|
412 |
static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num)
|
413 |
{ |
414 |
BDRVVPCState *s = bs->opaque; |
415 |
int64_t bat_offset; |
416 |
uint32_t index, bat_value; |
417 |
int ret;
|
418 |
uint8_t bitmap[s->bitmap_size]; |
419 |
|
420 |
// Check if sector_num is valid
|
421 |
if ((sector_num < 0) || (sector_num > bs->total_sectors)) |
422 |
return -1; |
423 |
|
424 |
// Write entry into in-memory BAT
|
425 |
index = (sector_num * 512) / s->block_size;
|
426 |
if (s->pagetable[index] != 0xFFFFFFFF) |
427 |
return -1; |
428 |
|
429 |
s->pagetable[index] = s->free_data_block_offset / 512;
|
430 |
|
431 |
// Initialize the block's bitmap
|
432 |
memset(bitmap, 0xff, s->bitmap_size);
|
433 |
ret = bdrv_pwrite_sync(bs->file, s->free_data_block_offset, bitmap, |
434 |
s->bitmap_size); |
435 |
if (ret < 0) { |
436 |
return ret;
|
437 |
} |
438 |
|
439 |
// Write new footer (the old one will be overwritten)
|
440 |
s->free_data_block_offset += s->block_size + s->bitmap_size; |
441 |
ret = rewrite_footer(bs); |
442 |
if (ret < 0) |
443 |
goto fail;
|
444 |
|
445 |
// Write BAT entry to disk
|
446 |
bat_offset = s->bat_offset + (4 * index);
|
447 |
bat_value = be32_to_cpu(s->pagetable[index]); |
448 |
ret = bdrv_pwrite_sync(bs->file, bat_offset, &bat_value, 4);
|
449 |
if (ret < 0) |
450 |
goto fail;
|
451 |
|
452 |
return get_sector_offset(bs, sector_num, 0); |
453 |
|
454 |
fail:
|
455 |
s->free_data_block_offset -= (s->block_size + s->bitmap_size); |
456 |
return -1; |
457 |
} |
458 |
|
459 |
static int vpc_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
460 |
{ |
461 |
BDRVVPCState *s = (BDRVVPCState *)bs->opaque; |
462 |
VHDFooter *footer = (VHDFooter *) s->footer_buf; |
463 |
|
464 |
if (cpu_to_be32(footer->type) != VHD_FIXED) {
|
465 |
bdi->cluster_size = s->block_size; |
466 |
} |
467 |
|
468 |
bdi->unallocated_blocks_are_zero = true;
|
469 |
return 0; |
470 |
} |
471 |
|
472 |
static int vpc_read(BlockDriverState *bs, int64_t sector_num, |
473 |
uint8_t *buf, int nb_sectors)
|
474 |
{ |
475 |
BDRVVPCState *s = bs->opaque; |
476 |
int ret;
|
477 |
int64_t offset; |
478 |
int64_t sectors, sectors_per_block; |
479 |
VHDFooter *footer = (VHDFooter *) s->footer_buf; |
480 |
|
481 |
if (cpu_to_be32(footer->type) == VHD_FIXED) {
|
482 |
return bdrv_read(bs->file, sector_num, buf, nb_sectors);
|
483 |
} |
484 |
while (nb_sectors > 0) { |
485 |
offset = get_sector_offset(bs, sector_num, 0);
|
486 |
|
487 |
sectors_per_block = s->block_size >> BDRV_SECTOR_BITS; |
488 |
sectors = sectors_per_block - (sector_num % sectors_per_block); |
489 |
if (sectors > nb_sectors) {
|
490 |
sectors = nb_sectors; |
491 |
} |
492 |
|
493 |
if (offset == -1) { |
494 |
memset(buf, 0, sectors * BDRV_SECTOR_SIZE);
|
495 |
} else {
|
496 |
ret = bdrv_pread(bs->file, offset, buf, |
497 |
sectors * BDRV_SECTOR_SIZE); |
498 |
if (ret != sectors * BDRV_SECTOR_SIZE) {
|
499 |
return -1; |
500 |
} |
501 |
} |
502 |
|
503 |
nb_sectors -= sectors; |
504 |
sector_num += sectors; |
505 |
buf += sectors * BDRV_SECTOR_SIZE; |
506 |
} |
507 |
return 0; |
508 |
} |
509 |
|
510 |
static coroutine_fn int vpc_co_read(BlockDriverState *bs, int64_t sector_num, |
511 |
uint8_t *buf, int nb_sectors)
|
512 |
{ |
513 |
int ret;
|
514 |
BDRVVPCState *s = bs->opaque; |
515 |
qemu_co_mutex_lock(&s->lock); |
516 |
ret = vpc_read(bs, sector_num, buf, nb_sectors); |
517 |
qemu_co_mutex_unlock(&s->lock); |
518 |
return ret;
|
519 |
} |
520 |
|
521 |
static int vpc_write(BlockDriverState *bs, int64_t sector_num, |
522 |
const uint8_t *buf, int nb_sectors) |
523 |
{ |
524 |
BDRVVPCState *s = bs->opaque; |
525 |
int64_t offset; |
526 |
int64_t sectors, sectors_per_block; |
527 |
int ret;
|
528 |
VHDFooter *footer = (VHDFooter *) s->footer_buf; |
529 |
|
530 |
if (cpu_to_be32(footer->type) == VHD_FIXED) {
|
531 |
return bdrv_write(bs->file, sector_num, buf, nb_sectors);
|
532 |
} |
533 |
while (nb_sectors > 0) { |
534 |
offset = get_sector_offset(bs, sector_num, 1);
|
535 |
|
536 |
sectors_per_block = s->block_size >> BDRV_SECTOR_BITS; |
537 |
sectors = sectors_per_block - (sector_num % sectors_per_block); |
538 |
if (sectors > nb_sectors) {
|
539 |
sectors = nb_sectors; |
540 |
} |
541 |
|
542 |
if (offset == -1) { |
543 |
offset = alloc_block(bs, sector_num); |
544 |
if (offset < 0) |
545 |
return -1; |
546 |
} |
547 |
|
548 |
ret = bdrv_pwrite(bs->file, offset, buf, sectors * BDRV_SECTOR_SIZE); |
549 |
if (ret != sectors * BDRV_SECTOR_SIZE) {
|
550 |
return -1; |
551 |
} |
552 |
|
553 |
nb_sectors -= sectors; |
554 |
sector_num += sectors; |
555 |
buf += sectors * BDRV_SECTOR_SIZE; |
556 |
} |
557 |
|
558 |
return 0; |
559 |
} |
560 |
|
561 |
static coroutine_fn int vpc_co_write(BlockDriverState *bs, int64_t sector_num, |
562 |
const uint8_t *buf, int nb_sectors) |
563 |
{ |
564 |
int ret;
|
565 |
BDRVVPCState *s = bs->opaque; |
566 |
qemu_co_mutex_lock(&s->lock); |
567 |
ret = vpc_write(bs, sector_num, buf, nb_sectors); |
568 |
qemu_co_mutex_unlock(&s->lock); |
569 |
return ret;
|
570 |
} |
571 |
|
572 |
/*
|
573 |
* Calculates the number of cylinders, heads and sectors per cylinder
|
574 |
* based on a given number of sectors. This is the algorithm described
|
575 |
* in the VHD specification.
|
576 |
*
|
577 |
* Note that the geometry doesn't always exactly match total_sectors but
|
578 |
* may round it down.
|
579 |
*
|
580 |
* Returns 0 on success, -EFBIG if the size is larger than ~2 TB. Override
|
581 |
* the hardware EIDE and ATA-2 limit of 16 heads (max disk size of 127 GB)
|
582 |
* and instead allow up to 255 heads.
|
583 |
*/
|
584 |
static int calculate_geometry(int64_t total_sectors, uint16_t* cyls, |
585 |
uint8_t* heads, uint8_t* secs_per_cyl) |
586 |
{ |
587 |
uint32_t cyls_times_heads; |
588 |
|
589 |
/* Allow a maximum disk size of approximately 2 TB */
|
590 |
if (total_sectors > 65535LL * 255 * 255) { |
591 |
return -EFBIG;
|
592 |
} |
593 |
|
594 |
if (total_sectors > 65535 * 16 * 63) { |
595 |
*secs_per_cyl = 255;
|
596 |
if (total_sectors > 65535 * 16 * 255) { |
597 |
*heads = 255;
|
598 |
} else {
|
599 |
*heads = 16;
|
600 |
} |
601 |
cyls_times_heads = total_sectors / *secs_per_cyl; |
602 |
} else {
|
603 |
*secs_per_cyl = 17;
|
604 |
cyls_times_heads = total_sectors / *secs_per_cyl; |
605 |
*heads = (cyls_times_heads + 1023) / 1024; |
606 |
|
607 |
if (*heads < 4) |
608 |
*heads = 4;
|
609 |
|
610 |
if (cyls_times_heads >= (*heads * 1024) || *heads > 16) { |
611 |
*secs_per_cyl = 31;
|
612 |
*heads = 16;
|
613 |
cyls_times_heads = total_sectors / *secs_per_cyl; |
614 |
} |
615 |
|
616 |
if (cyls_times_heads >= (*heads * 1024)) { |
617 |
*secs_per_cyl = 63;
|
618 |
*heads = 16;
|
619 |
cyls_times_heads = total_sectors / *secs_per_cyl; |
620 |
} |
621 |
} |
622 |
|
623 |
*cyls = cyls_times_heads / *heads; |
624 |
|
625 |
return 0; |
626 |
} |
627 |
|
628 |
static int create_dynamic_disk(int fd, uint8_t *buf, int64_t total_sectors) |
629 |
{ |
630 |
VHDDynDiskHeader *dyndisk_header = |
631 |
(VHDDynDiskHeader *) buf; |
632 |
size_t block_size, num_bat_entries; |
633 |
int i;
|
634 |
int ret = -EIO;
|
635 |
|
636 |
// Write the footer (twice: at the beginning and at the end)
|
637 |
block_size = 0x200000;
|
638 |
num_bat_entries = (total_sectors + block_size / 512) / (block_size / 512); |
639 |
|
640 |
if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) {
|
641 |
goto fail;
|
642 |
} |
643 |
|
644 |
if (lseek(fd, 1536 + ((num_bat_entries * 4 + 511) & ~511), SEEK_SET) < 0) { |
645 |
goto fail;
|
646 |
} |
647 |
if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) {
|
648 |
goto fail;
|
649 |
} |
650 |
|
651 |
// Write the initial BAT
|
652 |
if (lseek(fd, 3 * 512, SEEK_SET) < 0) { |
653 |
goto fail;
|
654 |
} |
655 |
|
656 |
memset(buf, 0xFF, 512); |
657 |
for (i = 0; i < (num_bat_entries * 4 + 511) / 512; i++) { |
658 |
if (write(fd, buf, 512) != 512) { |
659 |
goto fail;
|
660 |
} |
661 |
} |
662 |
|
663 |
// Prepare the Dynamic Disk Header
|
664 |
memset(buf, 0, 1024); |
665 |
|
666 |
memcpy(dyndisk_header->magic, "cxsparse", 8); |
667 |
|
668 |
/*
|
669 |
* Note: The spec is actually wrong here for data_offset, it says
|
670 |
* 0xFFFFFFFF, but MS tools expect all 64 bits to be set.
|
671 |
*/
|
672 |
dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFFFFFFFFFFULL);
|
673 |
dyndisk_header->table_offset = be64_to_cpu(3 * 512); |
674 |
dyndisk_header->version = be32_to_cpu(0x00010000);
|
675 |
dyndisk_header->block_size = be32_to_cpu(block_size); |
676 |
dyndisk_header->max_table_entries = be32_to_cpu(num_bat_entries); |
677 |
|
678 |
dyndisk_header->checksum = be32_to_cpu(vpc_checksum(buf, 1024));
|
679 |
|
680 |
// Write the header
|
681 |
if (lseek(fd, 512, SEEK_SET) < 0) { |
682 |
goto fail;
|
683 |
} |
684 |
|
685 |
if (write(fd, buf, 1024) != 1024) { |
686 |
goto fail;
|
687 |
} |
688 |
ret = 0;
|
689 |
|
690 |
fail:
|
691 |
return ret;
|
692 |
} |
693 |
|
694 |
static int create_fixed_disk(int fd, uint8_t *buf, int64_t total_size) |
695 |
{ |
696 |
int ret = -EIO;
|
697 |
|
698 |
/* Add footer to total size */
|
699 |
total_size += 512;
|
700 |
if (ftruncate(fd, total_size) != 0) { |
701 |
ret = -errno; |
702 |
goto fail;
|
703 |
} |
704 |
if (lseek(fd, -512, SEEK_END) < 0) { |
705 |
goto fail;
|
706 |
} |
707 |
if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) {
|
708 |
goto fail;
|
709 |
} |
710 |
|
711 |
ret = 0;
|
712 |
|
713 |
fail:
|
714 |
return ret;
|
715 |
} |
716 |
|
717 |
static int vpc_create(const char *filename, QEMUOptionParameter *options, |
718 |
Error **errp) |
719 |
{ |
720 |
uint8_t buf[1024];
|
721 |
VHDFooter *footer = (VHDFooter *) buf; |
722 |
QEMUOptionParameter *disk_type_param; |
723 |
int fd, i;
|
724 |
uint16_t cyls = 0;
|
725 |
uint8_t heads = 0;
|
726 |
uint8_t secs_per_cyl = 0;
|
727 |
int64_t total_sectors; |
728 |
int64_t total_size; |
729 |
int disk_type;
|
730 |
int ret = -EIO;
|
731 |
|
732 |
/* Read out options */
|
733 |
total_size = get_option_parameter(options, BLOCK_OPT_SIZE)->value.n; |
734 |
|
735 |
disk_type_param = get_option_parameter(options, BLOCK_OPT_SUBFMT); |
736 |
if (disk_type_param && disk_type_param->value.s) {
|
737 |
if (!strcmp(disk_type_param->value.s, "dynamic")) { |
738 |
disk_type = VHD_DYNAMIC; |
739 |
} else if (!strcmp(disk_type_param->value.s, "fixed")) { |
740 |
disk_type = VHD_FIXED; |
741 |
} else {
|
742 |
return -EINVAL;
|
743 |
} |
744 |
} else {
|
745 |
disk_type = VHD_DYNAMIC; |
746 |
} |
747 |
|
748 |
/* Create the file */
|
749 |
fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644);
|
750 |
if (fd < 0) { |
751 |
return -EIO;
|
752 |
} |
753 |
|
754 |
/*
|
755 |
* Calculate matching total_size and geometry. Increase the number of
|
756 |
* sectors requested until we get enough (or fail). This ensures that
|
757 |
* qemu-img convert doesn't truncate images, but rather rounds up.
|
758 |
*/
|
759 |
total_sectors = total_size / BDRV_SECTOR_SIZE; |
760 |
for (i = 0; total_sectors > (int64_t)cyls * heads * secs_per_cyl; i++) { |
761 |
if (calculate_geometry(total_sectors + i, &cyls, &heads,
|
762 |
&secs_per_cyl)) |
763 |
{ |
764 |
ret = -EFBIG; |
765 |
goto fail;
|
766 |
} |
767 |
} |
768 |
|
769 |
total_sectors = (int64_t) cyls * heads * secs_per_cyl; |
770 |
|
771 |
/* Prepare the Hard Disk Footer */
|
772 |
memset(buf, 0, 1024); |
773 |
|
774 |
memcpy(footer->creator, "conectix", 8); |
775 |
/* TODO Check if "qemu" creator_app is ok for VPC */
|
776 |
memcpy(footer->creator_app, "qemu", 4); |
777 |
memcpy(footer->creator_os, "Wi2k", 4); |
778 |
|
779 |
footer->features = be32_to_cpu(0x02);
|
780 |
footer->version = be32_to_cpu(0x00010000);
|
781 |
if (disk_type == VHD_DYNAMIC) {
|
782 |
footer->data_offset = be64_to_cpu(HEADER_SIZE); |
783 |
} else {
|
784 |
footer->data_offset = be64_to_cpu(0xFFFFFFFFFFFFFFFFULL);
|
785 |
} |
786 |
footer->timestamp = be32_to_cpu(time(NULL) - VHD_TIMESTAMP_BASE);
|
787 |
|
788 |
/* Version of Virtual PC 2007 */
|
789 |
footer->major = be16_to_cpu(0x0005);
|
790 |
footer->minor = be16_to_cpu(0x0003);
|
791 |
if (disk_type == VHD_DYNAMIC) {
|
792 |
footer->orig_size = be64_to_cpu(total_sectors * 512);
|
793 |
footer->size = be64_to_cpu(total_sectors * 512);
|
794 |
} else {
|
795 |
footer->orig_size = be64_to_cpu(total_size); |
796 |
footer->size = be64_to_cpu(total_size); |
797 |
} |
798 |
footer->cyls = be16_to_cpu(cyls); |
799 |
footer->heads = heads; |
800 |
footer->secs_per_cyl = secs_per_cyl; |
801 |
|
802 |
footer->type = be32_to_cpu(disk_type); |
803 |
|
804 |
#if defined(CONFIG_UUID)
|
805 |
uuid_generate(footer->uuid); |
806 |
#endif
|
807 |
|
808 |
footer->checksum = be32_to_cpu(vpc_checksum(buf, HEADER_SIZE)); |
809 |
|
810 |
if (disk_type == VHD_DYNAMIC) {
|
811 |
ret = create_dynamic_disk(fd, buf, total_sectors); |
812 |
} else {
|
813 |
ret = create_fixed_disk(fd, buf, total_size); |
814 |
} |
815 |
|
816 |
fail:
|
817 |
qemu_close(fd); |
818 |
return ret;
|
819 |
} |
820 |
|
821 |
static int vpc_has_zero_init(BlockDriverState *bs) |
822 |
{ |
823 |
BDRVVPCState *s = bs->opaque; |
824 |
VHDFooter *footer = (VHDFooter *) s->footer_buf; |
825 |
|
826 |
if (cpu_to_be32(footer->type) == VHD_FIXED) {
|
827 |
return bdrv_has_zero_init(bs->file);
|
828 |
} else {
|
829 |
return 1; |
830 |
} |
831 |
} |
832 |
|
833 |
static void vpc_close(BlockDriverState *bs) |
834 |
{ |
835 |
BDRVVPCState *s = bs->opaque; |
836 |
g_free(s->pagetable); |
837 |
#ifdef CACHE
|
838 |
g_free(s->pageentry_u8); |
839 |
#endif
|
840 |
|
841 |
migrate_del_blocker(s->migration_blocker); |
842 |
error_free(s->migration_blocker); |
843 |
} |
844 |
|
845 |
static QEMUOptionParameter vpc_create_options[] = {
|
846 |
{ |
847 |
.name = BLOCK_OPT_SIZE, |
848 |
.type = OPT_SIZE, |
849 |
.help = "Virtual disk size"
|
850 |
}, |
851 |
{ |
852 |
.name = BLOCK_OPT_SUBFMT, |
853 |
.type = OPT_STRING, |
854 |
.help = |
855 |
"Type of virtual hard disk format. Supported formats are "
|
856 |
"{dynamic (default) | fixed} "
|
857 |
}, |
858 |
{ NULL }
|
859 |
}; |
860 |
|
861 |
static BlockDriver bdrv_vpc = {
|
862 |
.format_name = "vpc",
|
863 |
.instance_size = sizeof(BDRVVPCState),
|
864 |
|
865 |
.bdrv_probe = vpc_probe, |
866 |
.bdrv_open = vpc_open, |
867 |
.bdrv_close = vpc_close, |
868 |
.bdrv_reopen_prepare = vpc_reopen_prepare, |
869 |
.bdrv_create = vpc_create, |
870 |
|
871 |
.bdrv_read = vpc_co_read, |
872 |
.bdrv_write = vpc_co_write, |
873 |
|
874 |
.bdrv_get_info = vpc_get_info, |
875 |
|
876 |
.create_options = vpc_create_options, |
877 |
.bdrv_has_zero_init = vpc_has_zero_init, |
878 |
}; |
879 |
|
880 |
static void bdrv_vpc_init(void) |
881 |
{ |
882 |
bdrv_register(&bdrv_vpc); |
883 |
} |
884 |
|
885 |
block_init(bdrv_vpc_init); |