David 'Digit' Turner | cb42a1b | 2010-12-23 02:54:08 +0100 | [diff] [blame] | 1 | |
| 2 | #include "qemu-common.h" |
David 'Digit' Turner | e1e03df | 2013-12-15 00:42:21 +0100 | [diff] [blame] | 3 | #include "block/block_int.h" |
David 'Digit' Turner | e90d665 | 2013-12-14 14:55:12 +0100 | [diff] [blame] | 4 | #include "qemu/module.h" |
David 'Digit' Turner | cb42a1b | 2010-12-23 02:54:08 +0100 | [diff] [blame] | 5 | |
| 6 | static int raw_open(BlockDriverState *bs, int flags) |
| 7 | { |
| 8 | bs->sg = bs->file->sg; |
| 9 | return 0; |
| 10 | } |
| 11 | |
| 12 | /* check for the user attempting to write something that looks like a |
| 13 | block format header to the beginning of the image and fail out. |
| 14 | */ |
| 15 | static int check_for_block_signature(BlockDriverState *bs, const uint8_t *buf) |
| 16 | { |
| 17 | static const uint8_t signatures[][4] = { |
| 18 | { 'Q', 'F', 'I', 0xfb }, /* qcow/qcow2 */ |
| 19 | { 'C', 'O', 'W', 'D' }, /* VMDK3 */ |
| 20 | { 'V', 'M', 'D', 'K' }, /* VMDK4 */ |
| 21 | { 'O', 'O', 'O', 'M' }, /* UML COW */ |
| 22 | {} |
| 23 | }; |
| 24 | int i; |
| 25 | |
| 26 | for (i = 0; signatures[i][0] != 0; i++) { |
| 27 | if (memcmp(buf, signatures[i], 4) == 0) { |
| 28 | return 1; |
| 29 | } |
| 30 | } |
| 31 | |
| 32 | return 0; |
| 33 | } |
| 34 | |
| 35 | static int check_write_unsafe(BlockDriverState *bs, int64_t sector_num, |
| 36 | const uint8_t *buf, int nb_sectors) |
| 37 | { |
| 38 | /* assume that if the user specifies the format explicitly, then assume |
| 39 | that they will continue to do so and provide no safety net */ |
| 40 | if (!bs->probed) { |
| 41 | return 0; |
| 42 | } |
| 43 | |
| 44 | if (sector_num == 0 && nb_sectors > 0) { |
| 45 | return check_for_block_signature(bs, buf); |
| 46 | } |
| 47 | |
| 48 | return 0; |
| 49 | } |
| 50 | |
| 51 | static int raw_read(BlockDriverState *bs, int64_t sector_num, |
| 52 | uint8_t *buf, int nb_sectors) |
| 53 | { |
| 54 | return bdrv_read(bs->file, sector_num, buf, nb_sectors); |
| 55 | } |
| 56 | |
| 57 | static int raw_write_scrubbed_bootsect(BlockDriverState *bs, |
| 58 | const uint8_t *buf) |
| 59 | { |
| 60 | uint8_t bootsect[512]; |
| 61 | |
| 62 | /* scrub the dangerous signature */ |
| 63 | memcpy(bootsect, buf, 512); |
| 64 | memset(bootsect, 0, 4); |
| 65 | |
| 66 | return bdrv_write(bs->file, 0, bootsect, 1); |
| 67 | } |
| 68 | |
| 69 | static int raw_write(BlockDriverState *bs, int64_t sector_num, |
| 70 | const uint8_t *buf, int nb_sectors) |
| 71 | { |
| 72 | if (check_write_unsafe(bs, sector_num, buf, nb_sectors)) { |
| 73 | int ret; |
| 74 | |
| 75 | ret = raw_write_scrubbed_bootsect(bs, buf); |
| 76 | if (ret < 0) { |
| 77 | return ret; |
| 78 | } |
| 79 | |
| 80 | ret = bdrv_write(bs->file, 1, buf + 512, nb_sectors - 1); |
| 81 | if (ret < 0) { |
| 82 | return ret; |
| 83 | } |
| 84 | |
| 85 | return ret + 512; |
| 86 | } |
| 87 | |
| 88 | return bdrv_write(bs->file, sector_num, buf, nb_sectors); |
| 89 | } |
| 90 | |
| 91 | static BlockDriverAIOCB *raw_aio_readv(BlockDriverState *bs, |
| 92 | int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, |
| 93 | BlockDriverCompletionFunc *cb, void *opaque) |
| 94 | { |
| 95 | return bdrv_aio_readv(bs->file, sector_num, qiov, nb_sectors, cb, opaque); |
| 96 | } |
| 97 | |
| 98 | typedef struct RawScrubberBounce |
| 99 | { |
| 100 | BlockDriverCompletionFunc *cb; |
| 101 | void *opaque; |
| 102 | QEMUIOVector qiov; |
| 103 | } RawScrubberBounce; |
| 104 | |
| 105 | static void raw_aio_writev_scrubbed(void *opaque, int ret) |
| 106 | { |
| 107 | RawScrubberBounce *b = opaque; |
| 108 | |
| 109 | if (ret < 0) { |
| 110 | b->cb(b->opaque, ret); |
| 111 | } else { |
| 112 | b->cb(b->opaque, ret + 512); |
| 113 | } |
| 114 | |
| 115 | qemu_iovec_destroy(&b->qiov); |
David 'Digit' Turner | aa8236d | 2014-01-10 17:02:29 +0100 | [diff] [blame] | 116 | g_free(b); |
David 'Digit' Turner | cb42a1b | 2010-12-23 02:54:08 +0100 | [diff] [blame] | 117 | } |
| 118 | |
| 119 | static BlockDriverAIOCB *raw_aio_writev(BlockDriverState *bs, |
| 120 | int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, |
| 121 | BlockDriverCompletionFunc *cb, void *opaque) |
| 122 | { |
| 123 | const uint8_t *first_buf; |
| 124 | int first_buf_index = 0, i; |
| 125 | |
| 126 | /* This is probably being paranoid, but handle cases of zero size |
| 127 | vectors. */ |
| 128 | for (i = 0; i < qiov->niov; i++) { |
| 129 | if (qiov->iov[i].iov_len) { |
| 130 | assert(qiov->iov[i].iov_len >= 512); |
| 131 | first_buf_index = i; |
| 132 | break; |
| 133 | } |
| 134 | } |
| 135 | |
| 136 | first_buf = qiov->iov[first_buf_index].iov_base; |
| 137 | |
| 138 | if (check_write_unsafe(bs, sector_num, first_buf, nb_sectors)) { |
| 139 | RawScrubberBounce *b; |
| 140 | int ret; |
| 141 | |
| 142 | /* write the first sector using sync I/O */ |
| 143 | ret = raw_write_scrubbed_bootsect(bs, first_buf); |
| 144 | if (ret < 0) { |
| 145 | return NULL; |
| 146 | } |
| 147 | |
| 148 | /* adjust request to be everything but first sector */ |
| 149 | |
David 'Digit' Turner | aa8236d | 2014-01-10 17:02:29 +0100 | [diff] [blame] | 150 | b = g_malloc(sizeof(*b)); |
David 'Digit' Turner | cb42a1b | 2010-12-23 02:54:08 +0100 | [diff] [blame] | 151 | b->cb = cb; |
| 152 | b->opaque = opaque; |
| 153 | |
| 154 | qemu_iovec_init(&b->qiov, qiov->nalloc); |
David 'Digit' Turner | 1befd34 | 2014-01-15 17:56:45 +0100 | [diff] [blame] | 155 | qemu_iovec_concat(&b->qiov, qiov, 0, qiov->size); |
David 'Digit' Turner | cb42a1b | 2010-12-23 02:54:08 +0100 | [diff] [blame] | 156 | |
| 157 | b->qiov.size -= 512; |
| 158 | b->qiov.iov[first_buf_index].iov_base += 512; |
| 159 | b->qiov.iov[first_buf_index].iov_len -= 512; |
| 160 | |
| 161 | return bdrv_aio_writev(bs->file, sector_num + 1, &b->qiov, |
| 162 | nb_sectors - 1, raw_aio_writev_scrubbed, b); |
| 163 | } |
| 164 | |
| 165 | return bdrv_aio_writev(bs->file, sector_num, qiov, nb_sectors, cb, opaque); |
| 166 | } |
| 167 | |
| 168 | static void raw_close(BlockDriverState *bs) |
| 169 | { |
| 170 | } |
| 171 | |
| 172 | static void raw_flush(BlockDriverState *bs) |
| 173 | { |
| 174 | bdrv_flush(bs->file); |
| 175 | } |
| 176 | |
| 177 | static BlockDriverAIOCB *raw_aio_flush(BlockDriverState *bs, |
| 178 | BlockDriverCompletionFunc *cb, void *opaque) |
| 179 | { |
| 180 | return bdrv_aio_flush(bs->file, cb, opaque); |
| 181 | } |
| 182 | |
| 183 | static int64_t raw_getlength(BlockDriverState *bs) |
| 184 | { |
| 185 | return bdrv_getlength(bs->file); |
| 186 | } |
| 187 | |
| 188 | static int raw_truncate(BlockDriverState *bs, int64_t offset) |
| 189 | { |
| 190 | return bdrv_truncate(bs->file, offset); |
| 191 | } |
| 192 | |
| 193 | static int raw_probe(const uint8_t *buf, int buf_size, const char *filename) |
| 194 | { |
| 195 | return 1; /* everything can be opened as raw image */ |
| 196 | } |
| 197 | |
| 198 | static int raw_is_inserted(BlockDriverState *bs) |
| 199 | { |
| 200 | return bdrv_is_inserted(bs->file); |
| 201 | } |
| 202 | |
| 203 | static int raw_eject(BlockDriverState *bs, int eject_flag) |
| 204 | { |
| 205 | return bdrv_eject(bs->file, eject_flag); |
| 206 | } |
| 207 | |
| 208 | static int raw_set_locked(BlockDriverState *bs, int locked) |
| 209 | { |
| 210 | bdrv_set_locked(bs->file, locked); |
| 211 | return 0; |
| 212 | } |
| 213 | |
| 214 | static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) |
| 215 | { |
| 216 | return bdrv_ioctl(bs->file, req, buf); |
| 217 | } |
| 218 | |
| 219 | static BlockDriverAIOCB *raw_aio_ioctl(BlockDriverState *bs, |
| 220 | unsigned long int req, void *buf, |
| 221 | BlockDriverCompletionFunc *cb, void *opaque) |
| 222 | { |
| 223 | return bdrv_aio_ioctl(bs->file, req, buf, cb, opaque); |
| 224 | } |
| 225 | |
| 226 | static int raw_create(const char *filename, QEMUOptionParameter *options) |
| 227 | { |
| 228 | return bdrv_create_file(filename, options); |
| 229 | } |
| 230 | |
| 231 | static QEMUOptionParameter raw_create_options[] = { |
| 232 | { |
| 233 | .name = BLOCK_OPT_SIZE, |
| 234 | .type = OPT_SIZE, |
| 235 | .help = "Virtual disk size" |
| 236 | }, |
| 237 | { NULL } |
| 238 | }; |
| 239 | |
| 240 | static int raw_has_zero_init(BlockDriverState *bs) |
| 241 | { |
| 242 | return bdrv_has_zero_init(bs->file); |
| 243 | } |
| 244 | |
| 245 | static BlockDriver bdrv_raw = { |
| 246 | .format_name = "raw", |
| 247 | |
David 'Digit' Turner | aa8236d | 2014-01-10 17:02:29 +0100 | [diff] [blame] | 248 | /* It's really 0, but we need to make g_malloc() happy */ |
David 'Digit' Turner | cb42a1b | 2010-12-23 02:54:08 +0100 | [diff] [blame] | 249 | .instance_size = 1, |
| 250 | |
| 251 | .bdrv_open = raw_open, |
| 252 | .bdrv_close = raw_close, |
| 253 | .bdrv_read = raw_read, |
| 254 | .bdrv_write = raw_write, |
| 255 | .bdrv_flush = raw_flush, |
| 256 | .bdrv_probe = raw_probe, |
| 257 | .bdrv_getlength = raw_getlength, |
| 258 | .bdrv_truncate = raw_truncate, |
| 259 | |
| 260 | .bdrv_aio_readv = raw_aio_readv, |
| 261 | .bdrv_aio_writev = raw_aio_writev, |
| 262 | .bdrv_aio_flush = raw_aio_flush, |
| 263 | |
| 264 | .bdrv_is_inserted = raw_is_inserted, |
| 265 | .bdrv_eject = raw_eject, |
| 266 | .bdrv_set_locked = raw_set_locked, |
| 267 | .bdrv_ioctl = raw_ioctl, |
| 268 | .bdrv_aio_ioctl = raw_aio_ioctl, |
| 269 | |
| 270 | .bdrv_create = raw_create, |
| 271 | .create_options = raw_create_options, |
| 272 | .bdrv_has_zero_init = raw_has_zero_init, |
| 273 | }; |
| 274 | |
| 275 | static void bdrv_raw_init(void) |
| 276 | { |
| 277 | bdrv_register(&bdrv_raw); |
| 278 | } |
| 279 | |
| 280 | block_init(bdrv_raw_init); |