Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2003 Sistina Software (UK) Limited. |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 3 | * Copyright (C) 2004, 2010-2011 Red Hat, Inc. All rights reserved. |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 4 | * |
| 5 | * This file is released under the GPL. |
| 6 | */ |
| 7 | |
| 8 | #include <linux/device-mapper.h> |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/blkdev.h> |
| 13 | #include <linux/bio.h> |
| 14 | #include <linux/slab.h> |
| 15 | |
| 16 | #define DM_MSG_PREFIX "flakey" |
| 17 | |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 18 | #define all_corrupt_bio_flags_match(bio, fc) \ |
| 19 | (((bio)->bi_rw & (fc)->corrupt_bio_flags) == (fc)->corrupt_bio_flags) |
| 20 | |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 21 | /* |
| 22 | * Flakey: Used for testing only, simulates intermittent, |
| 23 | * catastrophic device failure. |
| 24 | */ |
| 25 | struct flakey_c { |
| 26 | struct dm_dev *dev; |
| 27 | unsigned long start_time; |
| 28 | sector_t start; |
| 29 | unsigned up_interval; |
| 30 | unsigned down_interval; |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 31 | unsigned long flags; |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 32 | unsigned corrupt_bio_byte; |
| 33 | unsigned corrupt_bio_rw; |
| 34 | unsigned corrupt_bio_value; |
| 35 | unsigned corrupt_bio_flags; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 36 | }; |
| 37 | |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 38 | enum feature_flag_bits { |
| 39 | DROP_WRITES |
| 40 | }; |
| 41 | |
Mikulas Patocka | c7cfdf5 | 2012-12-21 20:23:39 +0000 | [diff] [blame] | 42 | struct per_bio_data { |
| 43 | bool bio_submitted; |
| 44 | }; |
| 45 | |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 46 | static int parse_features(struct dm_arg_set *as, struct flakey_c *fc, |
| 47 | struct dm_target *ti) |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 48 | { |
| 49 | int r; |
| 50 | unsigned argc; |
| 51 | const char *arg_name; |
| 52 | |
| 53 | static struct dm_arg _args[] = { |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 54 | {0, 6, "Invalid number of feature args"}, |
| 55 | {1, UINT_MAX, "Invalid corrupt bio byte"}, |
| 56 | {0, 255, "Invalid corrupt value to write into bio byte (0-255)"}, |
| 57 | {0, UINT_MAX, "Invalid corrupt bio flags mask"}, |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 58 | }; |
| 59 | |
| 60 | /* No feature arguments supplied. */ |
| 61 | if (!as->argc) |
| 62 | return 0; |
| 63 | |
| 64 | r = dm_read_arg_group(_args, as, &argc, &ti->error); |
| 65 | if (r) |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 66 | return r; |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 67 | |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 68 | while (argc) { |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 69 | arg_name = dm_shift_arg(as); |
| 70 | argc--; |
| 71 | |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 72 | /* |
| 73 | * drop_writes |
| 74 | */ |
| 75 | if (!strcasecmp(arg_name, "drop_writes")) { |
| 76 | if (test_and_set_bit(DROP_WRITES, &fc->flags)) { |
| 77 | ti->error = "Feature drop_writes duplicated"; |
| 78 | return -EINVAL; |
| 79 | } |
| 80 | |
| 81 | continue; |
| 82 | } |
| 83 | |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 84 | /* |
| 85 | * corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags> |
| 86 | */ |
| 87 | if (!strcasecmp(arg_name, "corrupt_bio_byte")) { |
Mike Snitzer | 68e58a2 | 2011-09-25 23:26:15 +0100 | [diff] [blame] | 88 | if (!argc) { |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 89 | ti->error = "Feature corrupt_bio_byte requires parameters"; |
Mike Snitzer | 68e58a2 | 2011-09-25 23:26:15 +0100 | [diff] [blame] | 90 | return -EINVAL; |
| 91 | } |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 92 | |
| 93 | r = dm_read_arg(_args + 1, as, &fc->corrupt_bio_byte, &ti->error); |
| 94 | if (r) |
| 95 | return r; |
| 96 | argc--; |
| 97 | |
| 98 | /* |
| 99 | * Direction r or w? |
| 100 | */ |
| 101 | arg_name = dm_shift_arg(as); |
| 102 | if (!strcasecmp(arg_name, "w")) |
| 103 | fc->corrupt_bio_rw = WRITE; |
| 104 | else if (!strcasecmp(arg_name, "r")) |
| 105 | fc->corrupt_bio_rw = READ; |
| 106 | else { |
| 107 | ti->error = "Invalid corrupt bio direction (r or w)"; |
| 108 | return -EINVAL; |
| 109 | } |
| 110 | argc--; |
| 111 | |
| 112 | /* |
| 113 | * Value of byte (0-255) to write in place of correct one. |
| 114 | */ |
| 115 | r = dm_read_arg(_args + 2, as, &fc->corrupt_bio_value, &ti->error); |
| 116 | if (r) |
| 117 | return r; |
| 118 | argc--; |
| 119 | |
| 120 | /* |
| 121 | * Only corrupt bios with these flags set. |
| 122 | */ |
| 123 | r = dm_read_arg(_args + 3, as, &fc->corrupt_bio_flags, &ti->error); |
| 124 | if (r) |
| 125 | return r; |
| 126 | argc--; |
| 127 | |
| 128 | continue; |
| 129 | } |
| 130 | |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 131 | ti->error = "Unrecognised flakey feature requested"; |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 132 | return -EINVAL; |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 133 | } |
| 134 | |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 135 | if (test_bit(DROP_WRITES, &fc->flags) && (fc->corrupt_bio_rw == WRITE)) { |
| 136 | ti->error = "drop_writes is incompatible with corrupt_bio_byte with the WRITE flag set"; |
| 137 | return -EINVAL; |
| 138 | } |
| 139 | |
| 140 | return 0; |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 141 | } |
| 142 | |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 143 | /* |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 144 | * Construct a flakey mapping: |
| 145 | * <dev_path> <offset> <up interval> <down interval> [<#feature args> [<arg>]*] |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 146 | * |
| 147 | * Feature args: |
| 148 | * [drop_writes] |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 149 | * [corrupt_bio_byte <Nth_byte> <direction> <value> <bio_flags>] |
| 150 | * |
| 151 | * Nth_byte starts from 1 for the first byte. |
| 152 | * Direction is r for READ or w for WRITE. |
| 153 | * bio_flags is ignored if 0. |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 154 | */ |
| 155 | static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
| 156 | { |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 157 | static struct dm_arg _args[] = { |
| 158 | {0, UINT_MAX, "Invalid up interval"}, |
| 159 | {0, UINT_MAX, "Invalid down interval"}, |
| 160 | }; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 161 | |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 162 | int r; |
| 163 | struct flakey_c *fc; |
| 164 | unsigned long long tmpll; |
| 165 | struct dm_arg_set as; |
| 166 | const char *devname; |
Mikulas Patocka | 31998ef | 2012-03-28 18:41:26 +0100 | [diff] [blame] | 167 | char dummy; |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 168 | |
| 169 | as.argc = argc; |
| 170 | as.argv = argv; |
| 171 | |
| 172 | if (argc < 4) { |
| 173 | ti->error = "Invalid argument count"; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 174 | return -EINVAL; |
| 175 | } |
| 176 | |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 177 | fc = kzalloc(sizeof(*fc), GFP_KERNEL); |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 178 | if (!fc) { |
Alasdair G Kergon | 75e3a0f | 2013-07-10 23:41:17 +0100 | [diff] [blame] | 179 | ti->error = "Cannot allocate context"; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 180 | return -ENOMEM; |
| 181 | } |
| 182 | fc->start_time = jiffies; |
| 183 | |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 184 | devname = dm_shift_arg(&as); |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 185 | |
Mikulas Patocka | 31998ef | 2012-03-28 18:41:26 +0100 | [diff] [blame] | 186 | if (sscanf(dm_shift_arg(&as), "%llu%c", &tmpll, &dummy) != 1) { |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 187 | ti->error = "Invalid device sector"; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 188 | goto bad; |
| 189 | } |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 190 | fc->start = tmpll; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 191 | |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 192 | r = dm_read_arg(_args, &as, &fc->up_interval, &ti->error); |
| 193 | if (r) |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 194 | goto bad; |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 195 | |
| 196 | r = dm_read_arg(_args, &as, &fc->down_interval, &ti->error); |
| 197 | if (r) |
| 198 | goto bad; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 199 | |
| 200 | if (!(fc->up_interval + fc->down_interval)) { |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 201 | ti->error = "Total (up + down) interval is zero"; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 202 | goto bad; |
| 203 | } |
| 204 | |
| 205 | if (fc->up_interval + fc->down_interval < fc->up_interval) { |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 206 | ti->error = "Interval overflow"; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 207 | goto bad; |
| 208 | } |
| 209 | |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 210 | r = parse_features(&as, fc, ti); |
Mike Snitzer | dfd068b | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 211 | if (r) |
| 212 | goto bad; |
| 213 | |
| 214 | if (dm_get_device(ti, devname, dm_table_get_mode(ti->table), &fc->dev)) { |
| 215 | ti->error = "Device lookup failed"; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 216 | goto bad; |
| 217 | } |
| 218 | |
Alasdair G Kergon | 55a62ee | 2013-03-01 22:45:47 +0000 | [diff] [blame] | 219 | ti->num_flush_bios = 1; |
| 220 | ti->num_discard_bios = 1; |
Mikulas Patocka | c7cfdf5 | 2012-12-21 20:23:39 +0000 | [diff] [blame] | 221 | ti->per_bio_data_size = sizeof(struct per_bio_data); |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 222 | ti->private = fc; |
| 223 | return 0; |
| 224 | |
| 225 | bad: |
| 226 | kfree(fc); |
| 227 | return -EINVAL; |
| 228 | } |
| 229 | |
| 230 | static void flakey_dtr(struct dm_target *ti) |
| 231 | { |
| 232 | struct flakey_c *fc = ti->private; |
| 233 | |
| 234 | dm_put_device(ti, fc->dev); |
| 235 | kfree(fc); |
| 236 | } |
| 237 | |
| 238 | static sector_t flakey_map_sector(struct dm_target *ti, sector_t bi_sector) |
| 239 | { |
| 240 | struct flakey_c *fc = ti->private; |
| 241 | |
Mike Snitzer | 30e4171 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 242 | return fc->start + dm_target_offset(ti, bi_sector); |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 243 | } |
| 244 | |
| 245 | static void flakey_map_bio(struct dm_target *ti, struct bio *bio) |
| 246 | { |
| 247 | struct flakey_c *fc = ti->private; |
| 248 | |
| 249 | bio->bi_bdev = fc->dev->bdev; |
| 250 | if (bio_sectors(bio)) |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 251 | bio->bi_iter.bi_sector = |
| 252 | flakey_map_sector(ti, bio->bi_iter.bi_sector); |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 253 | } |
| 254 | |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 255 | static void corrupt_bio_data(struct bio *bio, struct flakey_c *fc) |
| 256 | { |
| 257 | unsigned bio_bytes = bio_cur_bytes(bio); |
| 258 | char *data = bio_data(bio); |
| 259 | |
| 260 | /* |
| 261 | * Overwrite the Nth byte of the data returned. |
| 262 | */ |
| 263 | if (data && bio_bytes >= fc->corrupt_bio_byte) { |
| 264 | data[fc->corrupt_bio_byte - 1] = fc->corrupt_bio_value; |
| 265 | |
| 266 | DMDEBUG("Corrupting data bio=%p by writing %u to byte %u " |
| 267 | "(rw=%c bi_rw=%lu bi_sector=%llu cur_bytes=%u)\n", |
| 268 | bio, fc->corrupt_bio_value, fc->corrupt_bio_byte, |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 269 | (bio_data_dir(bio) == WRITE) ? 'w' : 'r', bio->bi_rw, |
| 270 | (unsigned long long)bio->bi_iter.bi_sector, bio_bytes); |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 271 | } |
| 272 | } |
| 273 | |
Mikulas Patocka | 7de3ee5 | 2012-12-21 20:23:41 +0000 | [diff] [blame] | 274 | static int flakey_map(struct dm_target *ti, struct bio *bio) |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 275 | { |
| 276 | struct flakey_c *fc = ti->private; |
| 277 | unsigned elapsed; |
Mikulas Patocka | c7cfdf5 | 2012-12-21 20:23:39 +0000 | [diff] [blame] | 278 | struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data)); |
| 279 | pb->bio_submitted = false; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 280 | |
| 281 | /* Are we alive ? */ |
| 282 | elapsed = (jiffies - fc->start_time) / HZ; |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 283 | if (elapsed % (fc->up_interval + fc->down_interval) >= fc->up_interval) { |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 284 | /* |
| 285 | * Flag this bio as submitted while down. |
| 286 | */ |
Mikulas Patocka | c7cfdf5 | 2012-12-21 20:23:39 +0000 | [diff] [blame] | 287 | pb->bio_submitted = true; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 288 | |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 289 | /* |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 290 | * Map reads as normal. |
| 291 | */ |
| 292 | if (bio_data_dir(bio) == READ) |
| 293 | goto map_bio; |
| 294 | |
| 295 | /* |
| 296 | * Drop writes? |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 297 | */ |
| 298 | if (test_bit(DROP_WRITES, &fc->flags)) { |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 299 | bio_endio(bio, 0); |
| 300 | return DM_MAPIO_SUBMITTED; |
| 301 | } |
| 302 | |
| 303 | /* |
| 304 | * Corrupt matching writes. |
| 305 | */ |
| 306 | if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == WRITE)) { |
| 307 | if (all_corrupt_bio_flags_match(bio, fc)) |
| 308 | corrupt_bio_data(bio, fc); |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 309 | goto map_bio; |
| 310 | } |
| 311 | |
| 312 | /* |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 313 | * By default, error all I/O. |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 314 | */ |
| 315 | return -EIO; |
| 316 | } |
| 317 | |
| 318 | map_bio: |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 319 | flakey_map_bio(ti, bio); |
| 320 | |
| 321 | return DM_MAPIO_REMAPPED; |
| 322 | } |
| 323 | |
Mikulas Patocka | 7de3ee5 | 2012-12-21 20:23:41 +0000 | [diff] [blame] | 324 | static int flakey_end_io(struct dm_target *ti, struct bio *bio, int error) |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 325 | { |
| 326 | struct flakey_c *fc = ti->private; |
Mikulas Patocka | c7cfdf5 | 2012-12-21 20:23:39 +0000 | [diff] [blame] | 327 | struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data)); |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 328 | |
| 329 | /* |
| 330 | * Corrupt successful READs while in down state. |
| 331 | * If flags were specified, only corrupt those that match. |
| 332 | */ |
Mikulas Patocka | c7cfdf5 | 2012-12-21 20:23:39 +0000 | [diff] [blame] | 333 | if (fc->corrupt_bio_byte && !error && pb->bio_submitted && |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 334 | (bio_data_dir(bio) == READ) && (fc->corrupt_bio_rw == READ) && |
| 335 | all_corrupt_bio_flags_match(bio, fc)) |
| 336 | corrupt_bio_data(bio, fc); |
| 337 | |
| 338 | return error; |
| 339 | } |
| 340 | |
Mikulas Patocka | fd7c092 | 2013-03-01 22:45:44 +0000 | [diff] [blame] | 341 | static void flakey_status(struct dm_target *ti, status_type_t type, |
| 342 | unsigned status_flags, char *result, unsigned maxlen) |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 343 | { |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 344 | unsigned sz = 0; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 345 | struct flakey_c *fc = ti->private; |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 346 | unsigned drop_writes; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 347 | |
| 348 | switch (type) { |
| 349 | case STATUSTYPE_INFO: |
| 350 | result[0] = '\0'; |
| 351 | break; |
| 352 | |
| 353 | case STATUSTYPE_TABLE: |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 354 | DMEMIT("%s %llu %u %u ", fc->dev->name, |
| 355 | (unsigned long long)fc->start, fc->up_interval, |
| 356 | fc->down_interval); |
| 357 | |
| 358 | drop_writes = test_bit(DROP_WRITES, &fc->flags); |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 359 | DMEMIT("%u ", drop_writes + (fc->corrupt_bio_byte > 0) * 5); |
| 360 | |
Mike Snitzer | b26f5e3 | 2011-08-02 12:32:05 +0100 | [diff] [blame] | 361 | if (drop_writes) |
| 362 | DMEMIT("drop_writes "); |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 363 | |
| 364 | if (fc->corrupt_bio_byte) |
| 365 | DMEMIT("corrupt_bio_byte %u %c %u %u ", |
| 366 | fc->corrupt_bio_byte, |
| 367 | (fc->corrupt_bio_rw == WRITE) ? 'w' : 'r', |
| 368 | fc->corrupt_bio_value, fc->corrupt_bio_flags); |
| 369 | |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 370 | break; |
| 371 | } |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 372 | } |
| 373 | |
| 374 | static int flakey_ioctl(struct dm_target *ti, unsigned int cmd, unsigned long arg) |
| 375 | { |
| 376 | struct flakey_c *fc = ti->private; |
Paolo Bonzini | ec8013b | 2012-01-12 16:01:29 +0100 | [diff] [blame] | 377 | struct dm_dev *dev = fc->dev; |
| 378 | int r = 0; |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 379 | |
Paolo Bonzini | ec8013b | 2012-01-12 16:01:29 +0100 | [diff] [blame] | 380 | /* |
| 381 | * Only pass ioctls through if the device sizes match exactly. |
| 382 | */ |
| 383 | if (fc->start || |
| 384 | ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT) |
| 385 | r = scsi_verify_blk_ioctl(NULL, cmd); |
| 386 | |
| 387 | return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg); |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 388 | } |
| 389 | |
| 390 | static int flakey_merge(struct dm_target *ti, struct bvec_merge_data *bvm, |
| 391 | struct bio_vec *biovec, int max_size) |
| 392 | { |
| 393 | struct flakey_c *fc = ti->private; |
| 394 | struct request_queue *q = bdev_get_queue(fc->dev->bdev); |
| 395 | |
| 396 | if (!q->merge_bvec_fn) |
| 397 | return max_size; |
| 398 | |
| 399 | bvm->bi_bdev = fc->dev->bdev; |
| 400 | bvm->bi_sector = flakey_map_sector(ti, bvm->bi_sector); |
| 401 | |
| 402 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); |
| 403 | } |
| 404 | |
| 405 | static int flakey_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data) |
| 406 | { |
| 407 | struct flakey_c *fc = ti->private; |
| 408 | |
| 409 | return fn(ti, fc->dev, fc->start, ti->len, data); |
| 410 | } |
| 411 | |
| 412 | static struct target_type flakey_target = { |
| 413 | .name = "flakey", |
Mikulas Patocka | fd7c092 | 2013-03-01 22:45:44 +0000 | [diff] [blame] | 414 | .version = {1, 3, 1}, |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 415 | .module = THIS_MODULE, |
| 416 | .ctr = flakey_ctr, |
| 417 | .dtr = flakey_dtr, |
| 418 | .map = flakey_map, |
Mike Snitzer | a399879 | 2011-08-02 12:32:06 +0100 | [diff] [blame] | 419 | .end_io = flakey_end_io, |
Josef Bacik | 3407ef5 | 2011-03-24 13:54:24 +0000 | [diff] [blame] | 420 | .status = flakey_status, |
| 421 | .ioctl = flakey_ioctl, |
| 422 | .merge = flakey_merge, |
| 423 | .iterate_devices = flakey_iterate_devices, |
| 424 | }; |
| 425 | |
| 426 | static int __init dm_flakey_init(void) |
| 427 | { |
| 428 | int r = dm_register_target(&flakey_target); |
| 429 | |
| 430 | if (r < 0) |
| 431 | DMERR("register failed %d", r); |
| 432 | |
| 433 | return r; |
| 434 | } |
| 435 | |
| 436 | static void __exit dm_flakey_exit(void) |
| 437 | { |
| 438 | dm_unregister_target(&flakey_target); |
| 439 | } |
| 440 | |
| 441 | /* Module hooks */ |
| 442 | module_init(dm_flakey_init); |
| 443 | module_exit(dm_flakey_exit); |
| 444 | |
| 445 | MODULE_DESCRIPTION(DM_NAME " flakey target"); |
| 446 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); |
| 447 | MODULE_LICENSE("GPL"); |