Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2001-2003 Sistina Software (UK) Limited. |
| 3 | * |
| 4 | * This file is released under the GPL. |
| 5 | */ |
| 6 | |
Mikulas Patocka | 586e80e | 2008-10-21 17:44:59 +0100 | [diff] [blame] | 7 | #include <linux/device-mapper.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | |
| 9 | #include <linux/module.h> |
| 10 | #include <linux/init.h> |
| 11 | #include <linux/blkdev.h> |
| 12 | #include <linux/bio.h> |
| 13 | #include <linux/slab.h> |
vignesh babu | 6f3c3f0 | 2007-10-19 22:38:44 +0100 | [diff] [blame] | 14 | #include <linux/log2.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 16 | #define DM_MSG_PREFIX "striped" |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 17 | #define DM_IO_ERROR_THRESHOLD 15 |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 18 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | struct stripe { |
| 20 | struct dm_dev *dev; |
| 21 | sector_t physical_start; |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 22 | |
| 23 | atomic_t error_count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | }; |
| 25 | |
| 26 | struct stripe_c { |
| 27 | uint32_t stripes; |
Mikulas Patocka | c96053b | 2010-08-12 04:14:21 +0100 | [diff] [blame] | 28 | int stripes_shift; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | |
| 30 | /* The size of this target / num. stripes */ |
| 31 | sector_t stripe_width; |
| 32 | |
| 33 | /* stripe chunk size */ |
| 34 | uint32_t chunk_shift; |
| 35 | sector_t chunk_mask; |
| 36 | |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 37 | /* Needed for handling events */ |
| 38 | struct dm_target *ti; |
| 39 | |
| 40 | /* Work struct used for triggering events*/ |
Tejun Heo | f521f07 | 2011-01-13 19:59:57 +0000 | [diff] [blame] | 41 | struct work_struct trigger_event; |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 42 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | struct stripe stripe[0]; |
| 44 | }; |
| 45 | |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 46 | /* |
| 47 | * An event is triggered whenever a drive |
| 48 | * drops out of a stripe volume. |
| 49 | */ |
| 50 | static void trigger_event(struct work_struct *work) |
| 51 | { |
Tejun Heo | f521f07 | 2011-01-13 19:59:57 +0000 | [diff] [blame] | 52 | struct stripe_c *sc = container_of(work, struct stripe_c, |
| 53 | trigger_event); |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 54 | dm_table_event(sc->ti->table); |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 55 | } |
| 56 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | static inline struct stripe_c *alloc_context(unsigned int stripes) |
| 58 | { |
| 59 | size_t len; |
| 60 | |
Mikulas Patocka | d63a5ce | 2008-10-21 17:44:57 +0100 | [diff] [blame] | 61 | if (dm_array_too_big(sizeof(struct stripe_c), sizeof(struct stripe), |
| 62 | stripes)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | return NULL; |
| 64 | |
| 65 | len = sizeof(struct stripe_c) + (sizeof(struct stripe) * stripes); |
| 66 | |
| 67 | return kmalloc(len, GFP_KERNEL); |
| 68 | } |
| 69 | |
| 70 | /* |
| 71 | * Parse a single <dev> <sector> pair |
| 72 | */ |
| 73 | static int get_stripe(struct dm_target *ti, struct stripe_c *sc, |
| 74 | unsigned int stripe, char **argv) |
| 75 | { |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 76 | unsigned long long start; |
Mikulas Patocka | 31998ef | 2012-03-28 18:41:26 +0100 | [diff] [blame] | 77 | char dummy; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | |
Mikulas Patocka | 31998ef | 2012-03-28 18:41:26 +0100 | [diff] [blame] | 79 | if (sscanf(argv[1], "%llu%c", &start, &dummy) != 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | return -EINVAL; |
| 81 | |
Nikanth Karthikesan | 8215d6e | 2010-03-06 02:32:27 +0000 | [diff] [blame] | 82 | if (dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | &sc->stripe[stripe].dev)) |
| 84 | return -ENXIO; |
| 85 | |
| 86 | sc->stripe[stripe].physical_start = start; |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 87 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | /* |
| 92 | * Construct a striped mapping. |
| 93 | * <number of stripes> <chunk size (2^^n)> [<dev_path> <offset>]+ |
| 94 | */ |
| 95 | static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
| 96 | { |
| 97 | struct stripe_c *sc; |
| 98 | sector_t width; |
| 99 | uint32_t stripes; |
| 100 | uint32_t chunk_size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | int r; |
| 102 | unsigned int i; |
| 103 | |
| 104 | if (argc < 2) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 105 | ti->error = "Not enough arguments"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | return -EINVAL; |
| 107 | } |
| 108 | |
majianpeng | 1a66a08 | 2012-07-27 15:07:59 +0100 | [diff] [blame] | 109 | if (kstrtouint(argv[0], 10, &stripes) || !stripes) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 110 | ti->error = "Invalid stripe count"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | return -EINVAL; |
| 112 | } |
| 113 | |
majianpeng | 1a66a08 | 2012-07-27 15:07:59 +0100 | [diff] [blame] | 114 | if (kstrtouint(argv[1], 10, &chunk_size)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 115 | ti->error = "Invalid chunk_size"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | return -EINVAL; |
| 117 | } |
| 118 | |
| 119 | /* |
| 120 | * chunk_size is a power of two |
| 121 | */ |
vignesh babu | 6f3c3f0 | 2007-10-19 22:38:44 +0100 | [diff] [blame] | 122 | if (!is_power_of_2(chunk_size) || |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | (chunk_size < (PAGE_SIZE >> SECTOR_SHIFT))) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 124 | ti->error = "Invalid chunk size"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | return -EINVAL; |
| 126 | } |
| 127 | |
Kevin Corry | a22c96c | 2006-03-27 01:18:01 -0800 | [diff] [blame] | 128 | if (ti->len & (chunk_size - 1)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 129 | ti->error = "Target length not divisible by " |
Kevin Corry | 8ba32fd | 2006-03-16 23:04:03 -0800 | [diff] [blame] | 130 | "chunk size"; |
| 131 | return -EINVAL; |
| 132 | } |
| 133 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | if (sector_div(width, stripes)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 135 | ti->error = "Target length not divisible by " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | "number of stripes"; |
| 137 | return -EINVAL; |
| 138 | } |
| 139 | |
| 140 | /* |
| 141 | * Do we have enough arguments for that many stripes ? |
| 142 | */ |
| 143 | if (argc != (2 + 2 * stripes)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 144 | ti->error = "Not enough destinations " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | "specified"; |
| 146 | return -EINVAL; |
| 147 | } |
| 148 | |
| 149 | sc = alloc_context(stripes); |
| 150 | if (!sc) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 151 | ti->error = "Memory allocation for striped context " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | "failed"; |
| 153 | return -ENOMEM; |
| 154 | } |
| 155 | |
Tejun Heo | f521f07 | 2011-01-13 19:59:57 +0000 | [diff] [blame] | 156 | INIT_WORK(&sc->trigger_event, trigger_event); |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 157 | |
| 158 | /* Set pointer to dm target; used in trigger_event */ |
| 159 | sc->ti = ti; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | sc->stripes = stripes; |
| 161 | sc->stripe_width = width; |
Mikulas Patocka | c96053b | 2010-08-12 04:14:21 +0100 | [diff] [blame] | 162 | |
| 163 | if (stripes & (stripes - 1)) |
| 164 | sc->stripes_shift = -1; |
Mikulas Patocka | 1df0548 | 2012-07-27 15:08:00 +0100 | [diff] [blame^] | 165 | else |
| 166 | sc->stripes_shift = __ffs(stripes); |
Mikulas Patocka | c96053b | 2010-08-12 04:14:21 +0100 | [diff] [blame] | 167 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | ti->split_io = chunk_size; |
Mikulas Patocka | 374bf7e | 2009-06-22 10:12:22 +0100 | [diff] [blame] | 169 | ti->num_flush_requests = stripes; |
Mikulas Patocka | 7b76ec1 | 2010-08-12 04:14:26 +0100 | [diff] [blame] | 170 | ti->num_discard_requests = stripes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | |
Mikulas Patocka | c96053b | 2010-08-12 04:14:21 +0100 | [diff] [blame] | 172 | sc->chunk_shift = ffs(chunk_size) - 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | sc->chunk_mask = ((sector_t) chunk_size) - 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | |
| 175 | /* |
| 176 | * Get the stripe destinations. |
| 177 | */ |
| 178 | for (i = 0; i < stripes; i++) { |
| 179 | argv += 2; |
| 180 | |
| 181 | r = get_stripe(ti, sc, i, argv); |
| 182 | if (r < 0) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 183 | ti->error = "Couldn't parse stripe destination"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | while (i--) |
| 185 | dm_put_device(ti, sc->stripe[i].dev); |
| 186 | kfree(sc); |
| 187 | return r; |
| 188 | } |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 189 | atomic_set(&(sc->stripe[i].error_count), 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | } |
| 191 | |
| 192 | ti->private = sc; |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 193 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | return 0; |
| 195 | } |
| 196 | |
| 197 | static void stripe_dtr(struct dm_target *ti) |
| 198 | { |
| 199 | unsigned int i; |
| 200 | struct stripe_c *sc = (struct stripe_c *) ti->private; |
| 201 | |
| 202 | for (i = 0; i < sc->stripes; i++) |
| 203 | dm_put_device(ti, sc->stripe[i].dev); |
| 204 | |
Tejun Heo | f521f07 | 2011-01-13 19:59:57 +0000 | [diff] [blame] | 205 | flush_work_sync(&sc->trigger_event); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | kfree(sc); |
| 207 | } |
| 208 | |
Mikulas Patocka | 6598852 | 2010-08-12 04:14:14 +0100 | [diff] [blame] | 209 | static void stripe_map_sector(struct stripe_c *sc, sector_t sector, |
| 210 | uint32_t *stripe, sector_t *result) |
| 211 | { |
| 212 | sector_t offset = dm_target_offset(sc->ti, sector); |
| 213 | sector_t chunk = offset >> sc->chunk_shift; |
| 214 | |
Mikulas Patocka | c96053b | 2010-08-12 04:14:21 +0100 | [diff] [blame] | 215 | if (sc->stripes_shift < 0) |
| 216 | *stripe = sector_div(chunk, sc->stripes); |
| 217 | else { |
Mikulas Patocka | 1df0548 | 2012-07-27 15:08:00 +0100 | [diff] [blame^] | 218 | *stripe = chunk & (sc->stripes - 1); |
Mikulas Patocka | c96053b | 2010-08-12 04:14:21 +0100 | [diff] [blame] | 219 | chunk >>= sc->stripes_shift; |
| 220 | } |
| 221 | |
Mikulas Patocka | 6598852 | 2010-08-12 04:14:14 +0100 | [diff] [blame] | 222 | *result = (chunk << sc->chunk_shift) | (offset & sc->chunk_mask); |
| 223 | } |
| 224 | |
Mikulas Patocka | 7b76ec1 | 2010-08-12 04:14:26 +0100 | [diff] [blame] | 225 | static void stripe_map_range_sector(struct stripe_c *sc, sector_t sector, |
| 226 | uint32_t target_stripe, sector_t *result) |
| 227 | { |
| 228 | uint32_t stripe; |
| 229 | |
| 230 | stripe_map_sector(sc, sector, &stripe, result); |
| 231 | if (stripe == target_stripe) |
| 232 | return; |
| 233 | *result &= ~sc->chunk_mask; /* round down */ |
| 234 | if (target_stripe < stripe) |
| 235 | *result += sc->chunk_mask + 1; /* next chunk */ |
| 236 | } |
| 237 | |
| 238 | static int stripe_map_discard(struct stripe_c *sc, struct bio *bio, |
| 239 | uint32_t target_stripe) |
| 240 | { |
| 241 | sector_t begin, end; |
| 242 | |
| 243 | stripe_map_range_sector(sc, bio->bi_sector, target_stripe, &begin); |
| 244 | stripe_map_range_sector(sc, bio->bi_sector + bio_sectors(bio), |
| 245 | target_stripe, &end); |
| 246 | if (begin < end) { |
| 247 | bio->bi_bdev = sc->stripe[target_stripe].dev->bdev; |
| 248 | bio->bi_sector = begin + sc->stripe[target_stripe].physical_start; |
| 249 | bio->bi_size = to_bytes(end - begin); |
| 250 | return DM_MAPIO_REMAPPED; |
| 251 | } else { |
| 252 | /* The range doesn't map to the target stripe */ |
| 253 | bio_endio(bio, 0); |
| 254 | return DM_MAPIO_SUBMITTED; |
| 255 | } |
| 256 | } |
| 257 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | static int stripe_map(struct dm_target *ti, struct bio *bio, |
| 259 | union map_info *map_context) |
| 260 | { |
Mikulas Patocka | 6598852 | 2010-08-12 04:14:14 +0100 | [diff] [blame] | 261 | struct stripe_c *sc = ti->private; |
Mikulas Patocka | 374bf7e | 2009-06-22 10:12:22 +0100 | [diff] [blame] | 262 | uint32_t stripe; |
Mike Snitzer | 57cba5d | 2010-08-12 04:14:04 +0100 | [diff] [blame] | 263 | unsigned target_request_nr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | |
Tejun Heo | d87f4c1 | 2010-09-03 11:56:19 +0200 | [diff] [blame] | 265 | if (bio->bi_rw & REQ_FLUSH) { |
Mike Snitzer | 57cba5d | 2010-08-12 04:14:04 +0100 | [diff] [blame] | 266 | target_request_nr = map_context->target_request_nr; |
| 267 | BUG_ON(target_request_nr >= sc->stripes); |
| 268 | bio->bi_bdev = sc->stripe[target_request_nr].dev->bdev; |
Mikulas Patocka | 374bf7e | 2009-06-22 10:12:22 +0100 | [diff] [blame] | 269 | return DM_MAPIO_REMAPPED; |
| 270 | } |
Mikulas Patocka | 7b76ec1 | 2010-08-12 04:14:26 +0100 | [diff] [blame] | 271 | if (unlikely(bio->bi_rw & REQ_DISCARD)) { |
| 272 | target_request_nr = map_context->target_request_nr; |
| 273 | BUG_ON(target_request_nr >= sc->stripes); |
| 274 | return stripe_map_discard(sc, bio, target_request_nr); |
| 275 | } |
Mikulas Patocka | 374bf7e | 2009-06-22 10:12:22 +0100 | [diff] [blame] | 276 | |
Mikulas Patocka | 6598852 | 2010-08-12 04:14:14 +0100 | [diff] [blame] | 277 | stripe_map_sector(sc, bio->bi_sector, &stripe, &bio->bi_sector); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | |
Mikulas Patocka | 6598852 | 2010-08-12 04:14:14 +0100 | [diff] [blame] | 279 | bio->bi_sector += sc->stripe[stripe].physical_start; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | bio->bi_bdev = sc->stripe[stripe].dev->bdev; |
Mikulas Patocka | 6598852 | 2010-08-12 04:14:14 +0100 | [diff] [blame] | 281 | |
Kiyoshi Ueda | d2a7ad2 | 2006-12-08 02:41:06 -0800 | [diff] [blame] | 282 | return DM_MAPIO_REMAPPED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | } |
| 284 | |
Brian Wood | 4f7f5c6 | 2008-02-08 02:11:24 +0000 | [diff] [blame] | 285 | /* |
| 286 | * Stripe status: |
| 287 | * |
| 288 | * INFO |
| 289 | * #stripes [stripe_name <stripe_name>] [group word count] |
| 290 | * [error count 'A|D' <error count 'A|D'>] |
| 291 | * |
| 292 | * TABLE |
| 293 | * #stripes [stripe chunk size] |
| 294 | * [stripe_name physical_start <stripe_name physical_start>] |
| 295 | * |
| 296 | */ |
| 297 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | static int stripe_status(struct dm_target *ti, |
| 299 | status_type_t type, char *result, unsigned int maxlen) |
| 300 | { |
| 301 | struct stripe_c *sc = (struct stripe_c *) ti->private; |
Brian Wood | 4f7f5c6 | 2008-02-08 02:11:24 +0000 | [diff] [blame] | 302 | char buffer[sc->stripes + 1]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | unsigned int sz = 0; |
| 304 | unsigned int i; |
| 305 | |
| 306 | switch (type) { |
| 307 | case STATUSTYPE_INFO: |
Brian Wood | 4f7f5c6 | 2008-02-08 02:11:24 +0000 | [diff] [blame] | 308 | DMEMIT("%d ", sc->stripes); |
| 309 | for (i = 0; i < sc->stripes; i++) { |
| 310 | DMEMIT("%s ", sc->stripe[i].dev->name); |
| 311 | buffer[i] = atomic_read(&(sc->stripe[i].error_count)) ? |
| 312 | 'D' : 'A'; |
| 313 | } |
| 314 | buffer[i] = '\0'; |
| 315 | DMEMIT("1 %s", buffer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | break; |
| 317 | |
| 318 | case STATUSTYPE_TABLE: |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 319 | DMEMIT("%d %llu", sc->stripes, |
| 320 | (unsigned long long)sc->chunk_mask + 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | for (i = 0; i < sc->stripes; i++) |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 322 | DMEMIT(" %s %llu", sc->stripe[i].dev->name, |
| 323 | (unsigned long long)sc->stripe[i].physical_start); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | break; |
| 325 | } |
| 326 | return 0; |
| 327 | } |
| 328 | |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 329 | static int stripe_end_io(struct dm_target *ti, struct bio *bio, |
| 330 | int error, union map_info *map_context) |
| 331 | { |
| 332 | unsigned i; |
| 333 | char major_minor[16]; |
| 334 | struct stripe_c *sc = ti->private; |
| 335 | |
| 336 | if (!error) |
| 337 | return 0; /* I/O complete */ |
| 338 | |
Christoph Hellwig | 7b6d91d | 2010-08-07 18:20:39 +0200 | [diff] [blame] | 339 | if ((error == -EWOULDBLOCK) && (bio->bi_rw & REQ_RAHEAD)) |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 340 | return error; |
| 341 | |
| 342 | if (error == -EOPNOTSUPP) |
| 343 | return error; |
| 344 | |
| 345 | memset(major_minor, 0, sizeof(major_minor)); |
| 346 | sprintf(major_minor, "%d:%d", |
Tejun Heo | f331c02 | 2008-09-03 09:01:48 +0200 | [diff] [blame] | 347 | MAJOR(disk_devt(bio->bi_bdev->bd_disk)), |
| 348 | MINOR(disk_devt(bio->bi_bdev->bd_disk))); |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 349 | |
| 350 | /* |
| 351 | * Test to see which stripe drive triggered the event |
| 352 | * and increment error count for all stripes on that device. |
| 353 | * If the error count for a given device exceeds the threshold |
| 354 | * value we will no longer trigger any further events. |
| 355 | */ |
| 356 | for (i = 0; i < sc->stripes; i++) |
| 357 | if (!strcmp(sc->stripe[i].dev->name, major_minor)) { |
| 358 | atomic_inc(&(sc->stripe[i].error_count)); |
| 359 | if (atomic_read(&(sc->stripe[i].error_count)) < |
| 360 | DM_IO_ERROR_THRESHOLD) |
Tejun Heo | f521f07 | 2011-01-13 19:59:57 +0000 | [diff] [blame] | 361 | schedule_work(&sc->trigger_event); |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 362 | } |
| 363 | |
| 364 | return error; |
| 365 | } |
| 366 | |
Mike Snitzer | af4874e | 2009-06-22 10:12:33 +0100 | [diff] [blame] | 367 | static int stripe_iterate_devices(struct dm_target *ti, |
| 368 | iterate_devices_callout_fn fn, void *data) |
| 369 | { |
| 370 | struct stripe_c *sc = ti->private; |
| 371 | int ret = 0; |
| 372 | unsigned i = 0; |
| 373 | |
Mike Snitzer | 5dea271 | 2009-07-23 20:30:42 +0100 | [diff] [blame] | 374 | do { |
Mike Snitzer | af4874e | 2009-06-22 10:12:33 +0100 | [diff] [blame] | 375 | ret = fn(ti, sc->stripe[i].dev, |
Mike Snitzer | 5dea271 | 2009-07-23 20:30:42 +0100 | [diff] [blame] | 376 | sc->stripe[i].physical_start, |
| 377 | sc->stripe_width, data); |
| 378 | } while (!ret && ++i < sc->stripes); |
Mike Snitzer | af4874e | 2009-06-22 10:12:33 +0100 | [diff] [blame] | 379 | |
| 380 | return ret; |
| 381 | } |
| 382 | |
Mike Snitzer | 40bea43 | 2009-09-04 20:40:25 +0100 | [diff] [blame] | 383 | static void stripe_io_hints(struct dm_target *ti, |
| 384 | struct queue_limits *limits) |
| 385 | { |
| 386 | struct stripe_c *sc = ti->private; |
| 387 | unsigned chunk_size = (sc->chunk_mask + 1) << 9; |
| 388 | |
| 389 | blk_limits_io_min(limits, chunk_size); |
Martin K. Petersen | 3c5820c | 2009-09-11 21:54:52 +0200 | [diff] [blame] | 390 | blk_limits_io_opt(limits, chunk_size * sc->stripes); |
Mike Snitzer | 40bea43 | 2009-09-04 20:40:25 +0100 | [diff] [blame] | 391 | } |
| 392 | |
Mustafa Mesanovic | 2991520 | 2011-03-24 13:54:35 +0000 | [diff] [blame] | 393 | static int stripe_merge(struct dm_target *ti, struct bvec_merge_data *bvm, |
| 394 | struct bio_vec *biovec, int max_size) |
| 395 | { |
| 396 | struct stripe_c *sc = ti->private; |
| 397 | sector_t bvm_sector = bvm->bi_sector; |
| 398 | uint32_t stripe; |
| 399 | struct request_queue *q; |
| 400 | |
| 401 | stripe_map_sector(sc, bvm_sector, &stripe, &bvm_sector); |
| 402 | |
| 403 | q = bdev_get_queue(sc->stripe[stripe].dev->bdev); |
| 404 | if (!q->merge_bvec_fn) |
| 405 | return max_size; |
| 406 | |
| 407 | bvm->bi_bdev = sc->stripe[stripe].dev->bdev; |
| 408 | bvm->bi_sector = sc->stripe[stripe].physical_start + bvm_sector; |
| 409 | |
| 410 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); |
| 411 | } |
| 412 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | static struct target_type stripe_target = { |
| 414 | .name = "striped", |
Mustafa Mesanovic | 2991520 | 2011-03-24 13:54:35 +0000 | [diff] [blame] | 415 | .version = {1, 4, 0}, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 416 | .module = THIS_MODULE, |
| 417 | .ctr = stripe_ctr, |
| 418 | .dtr = stripe_dtr, |
| 419 | .map = stripe_map, |
Brian Wood | a25eb94 | 2008-02-08 02:11:22 +0000 | [diff] [blame] | 420 | .end_io = stripe_end_io, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | .status = stripe_status, |
Mike Snitzer | af4874e | 2009-06-22 10:12:33 +0100 | [diff] [blame] | 422 | .iterate_devices = stripe_iterate_devices, |
Mike Snitzer | 40bea43 | 2009-09-04 20:40:25 +0100 | [diff] [blame] | 423 | .io_hints = stripe_io_hints, |
Mustafa Mesanovic | 2991520 | 2011-03-24 13:54:35 +0000 | [diff] [blame] | 424 | .merge = stripe_merge, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | }; |
| 426 | |
| 427 | int __init dm_stripe_init(void) |
| 428 | { |
| 429 | int r; |
| 430 | |
| 431 | r = dm_register_target(&stripe_target); |
Heinz Mauelshagen | 6edebde | 2008-11-13 23:38:56 +0000 | [diff] [blame] | 432 | if (r < 0) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 433 | DMWARN("target registration failed"); |
Heinz Mauelshagen | 6edebde | 2008-11-13 23:38:56 +0000 | [diff] [blame] | 434 | return r; |
| 435 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 436 | |
| 437 | return r; |
| 438 | } |
| 439 | |
| 440 | void dm_stripe_exit(void) |
| 441 | { |
Mikulas Patocka | 10d3bd0 | 2009-01-06 03:04:58 +0000 | [diff] [blame] | 442 | dm_unregister_target(&stripe_target); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | } |