Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. |
Milan Broz | 784aae7 | 2009-01-06 03:05:12 +0000 | [diff] [blame] | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * |
| 5 | * This file is released under the GPL. |
| 6 | */ |
| 7 | |
| 8 | #include "dm.h" |
Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 9 | #include "dm-uevent.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/module.h> |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 13 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/moduleparam.h> |
| 15 | #include <linux/blkpg.h> |
| 16 | #include <linux/bio.h> |
| 17 | #include <linux/buffer_head.h> |
| 18 | #include <linux/mempool.h> |
| 19 | #include <linux/slab.h> |
| 20 | #include <linux/idr.h> |
Darrick J. Wong | 3ac51e7 | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 21 | #include <linux/hdreg.h> |
Li Zefan | 5578213 | 2009-06-09 13:43:05 +0800 | [diff] [blame] | 22 | |
| 23 | #include <trace/events/block.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 25 | #define DM_MSG_PREFIX "core" |
| 26 | |
Milan Broz | 60935eb | 2009-06-22 10:12:30 +0100 | [diff] [blame^] | 27 | /* |
| 28 | * Cookies are numeric values sent with CHANGE and REMOVE |
| 29 | * uevents while resuming, removing or renaming the device. |
| 30 | */ |
| 31 | #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" |
| 32 | #define DM_COOKIE_LENGTH 24 |
| 33 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | static const char *_name = DM_NAME; |
| 35 | |
| 36 | static unsigned int major = 0; |
| 37 | static unsigned int _major = 0; |
| 38 | |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 39 | static DEFINE_SPINLOCK(_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | /* |
Kiyoshi Ueda | 8fbf26a | 2009-01-06 03:05:06 +0000 | [diff] [blame] | 41 | * For bio-based dm. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | * One of these is allocated per bio. |
| 43 | */ |
| 44 | struct dm_io { |
| 45 | struct mapped_device *md; |
| 46 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | atomic_t io_count; |
Richard Kennedy | 6ae2fa6 | 2008-07-21 12:00:28 +0100 | [diff] [blame] | 48 | struct bio *bio; |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 49 | unsigned long start_time; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | }; |
| 51 | |
| 52 | /* |
Kiyoshi Ueda | 8fbf26a | 2009-01-06 03:05:06 +0000 | [diff] [blame] | 53 | * For bio-based dm. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | * One of these is allocated per target within a bio. Hopefully |
| 55 | * this will be simplified out one day. |
| 56 | */ |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 57 | struct dm_target_io { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | struct dm_io *io; |
| 59 | struct dm_target *ti; |
| 60 | union map_info info; |
| 61 | }; |
| 62 | |
Kiyoshi Ueda | 8fbf26a | 2009-01-06 03:05:06 +0000 | [diff] [blame] | 63 | /* |
| 64 | * For request-based dm. |
| 65 | * One of these is allocated per request. |
| 66 | */ |
| 67 | struct dm_rq_target_io { |
| 68 | struct mapped_device *md; |
| 69 | struct dm_target *ti; |
| 70 | struct request *orig, clone; |
| 71 | int error; |
| 72 | union map_info info; |
| 73 | }; |
| 74 | |
| 75 | /* |
| 76 | * For request-based dm. |
| 77 | * One of these is allocated per bio. |
| 78 | */ |
| 79 | struct dm_rq_clone_bio_info { |
| 80 | struct bio *orig; |
| 81 | struct request *rq; |
| 82 | }; |
| 83 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | union map_info *dm_get_mapinfo(struct bio *bio) |
| 85 | { |
Alasdair G Kergon | 17b2f66 | 2006-06-26 00:27:33 -0700 | [diff] [blame] | 86 | if (bio && bio->bi_private) |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 87 | return &((struct dm_target_io *)bio->bi_private)->info; |
Alasdair G Kergon | 17b2f66 | 2006-06-26 00:27:33 -0700 | [diff] [blame] | 88 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | } |
| 90 | |
Jeff Mahoney | ba61fdd | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 91 | #define MINOR_ALLOCED ((void *)-1) |
| 92 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | /* |
| 94 | * Bits for the md->flags field. |
| 95 | */ |
Alasdair G Kergon | 1eb787e | 2009-04-09 00:27:14 +0100 | [diff] [blame] | 96 | #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | #define DMF_SUSPENDED 1 |
Alasdair G Kergon | aa8d7c2 | 2006-01-06 00:20:06 -0800 | [diff] [blame] | 98 | #define DMF_FROZEN 2 |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 99 | #define DMF_FREEING 3 |
Alasdair G Kergon | 5c6bd75 | 2006-06-26 00:27:34 -0700 | [diff] [blame] | 100 | #define DMF_DELETING 4 |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 101 | #define DMF_NOFLUSH_SUSPENDING 5 |
Alasdair G Kergon | 1eb787e | 2009-04-09 00:27:14 +0100 | [diff] [blame] | 102 | #define DMF_QUEUE_IO_TO_THREAD 6 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | |
Milan Broz | 304f3f6 | 2008-02-08 02:11:17 +0000 | [diff] [blame] | 104 | /* |
| 105 | * Work processed by per-device workqueue. |
| 106 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | struct mapped_device { |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 108 | struct rw_semaphore io_lock; |
Daniel Walker | e61290a | 2008-02-08 02:10:08 +0000 | [diff] [blame] | 109 | struct mutex suspend_lock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | rwlock_t map_lock; |
| 111 | atomic_t holders; |
Alasdair G Kergon | 5c6bd75 | 2006-06-26 00:27:34 -0700 | [diff] [blame] | 112 | atomic_t open_count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | |
| 114 | unsigned long flags; |
| 115 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 116 | struct request_queue *queue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | struct gendisk *disk; |
Mike Anderson | 7e51f25 | 2006-03-27 01:17:52 -0800 | [diff] [blame] | 118 | char name[16]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | |
| 120 | void *interface_ptr; |
| 121 | |
| 122 | /* |
| 123 | * A list of ios that arrived while we were suspended. |
| 124 | */ |
| 125 | atomic_t pending; |
| 126 | wait_queue_head_t wait; |
Mikulas Patocka | 53d5914 | 2009-04-02 19:55:37 +0100 | [diff] [blame] | 127 | struct work_struct work; |
Kiyoshi Ueda | 7485936 | 2006-12-08 02:41:02 -0800 | [diff] [blame] | 128 | struct bio_list deferred; |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 129 | spinlock_t deferred_lock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | |
| 131 | /* |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 132 | * An error from the barrier request currently being processed. |
| 133 | */ |
| 134 | int barrier_error; |
| 135 | |
| 136 | /* |
Milan Broz | 304f3f6 | 2008-02-08 02:11:17 +0000 | [diff] [blame] | 137 | * Processing queue (flush/barriers) |
| 138 | */ |
| 139 | struct workqueue_struct *wq; |
| 140 | |
| 141 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | * The current mapping. |
| 143 | */ |
| 144 | struct dm_table *map; |
| 145 | |
| 146 | /* |
| 147 | * io objects are allocated from here. |
| 148 | */ |
| 149 | mempool_t *io_pool; |
| 150 | mempool_t *tio_pool; |
| 151 | |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 152 | struct bio_set *bs; |
| 153 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | /* |
| 155 | * Event handling. |
| 156 | */ |
| 157 | atomic_t event_nr; |
| 158 | wait_queue_head_t eventq; |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 159 | atomic_t uevent_seq; |
| 160 | struct list_head uevent_list; |
| 161 | spinlock_t uevent_lock; /* Protect access to uevent_list */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | |
| 163 | /* |
| 164 | * freeze/thaw support require holding onto a super block |
| 165 | */ |
| 166 | struct super_block *frozen_sb; |
Mikulas Patocka | db8fef4 | 2009-06-22 10:12:15 +0100 | [diff] [blame] | 167 | struct block_device *bdev; |
Darrick J. Wong | 3ac51e7 | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 168 | |
| 169 | /* forced geometry settings */ |
| 170 | struct hd_geometry geometry; |
Milan Broz | 784aae7 | 2009-01-06 03:05:12 +0000 | [diff] [blame] | 171 | |
| 172 | /* sysfs handle */ |
| 173 | struct kobject kobj; |
Mikulas Patocka | 52b1fd5 | 2009-06-22 10:12:21 +0100 | [diff] [blame] | 174 | |
| 175 | /* zero-length barrier that will be cloned and submitted to targets */ |
| 176 | struct bio barrier_bio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 177 | }; |
| 178 | |
| 179 | #define MIN_IOS 256 |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 180 | static struct kmem_cache *_io_cache; |
| 181 | static struct kmem_cache *_tio_cache; |
Kiyoshi Ueda | 8fbf26a | 2009-01-06 03:05:06 +0000 | [diff] [blame] | 182 | static struct kmem_cache *_rq_tio_cache; |
| 183 | static struct kmem_cache *_rq_bio_info_cache; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | static int __init local_init(void) |
| 186 | { |
Kiyoshi Ueda | 51157b4 | 2008-10-21 17:45:08 +0100 | [diff] [blame] | 187 | int r = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | /* allocate a slab for the dm_ios */ |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 190 | _io_cache = KMEM_CACHE(dm_io, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | if (!_io_cache) |
Kiyoshi Ueda | 51157b4 | 2008-10-21 17:45:08 +0100 | [diff] [blame] | 192 | return r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | |
| 194 | /* allocate a slab for the target ios */ |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 195 | _tio_cache = KMEM_CACHE(dm_target_io, 0); |
Kiyoshi Ueda | 51157b4 | 2008-10-21 17:45:08 +0100 | [diff] [blame] | 196 | if (!_tio_cache) |
| 197 | goto out_free_io_cache; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | |
Kiyoshi Ueda | 8fbf26a | 2009-01-06 03:05:06 +0000 | [diff] [blame] | 199 | _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
| 200 | if (!_rq_tio_cache) |
| 201 | goto out_free_tio_cache; |
| 202 | |
| 203 | _rq_bio_info_cache = KMEM_CACHE(dm_rq_clone_bio_info, 0); |
| 204 | if (!_rq_bio_info_cache) |
| 205 | goto out_free_rq_tio_cache; |
| 206 | |
Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 207 | r = dm_uevent_init(); |
Kiyoshi Ueda | 51157b4 | 2008-10-21 17:45:08 +0100 | [diff] [blame] | 208 | if (r) |
Kiyoshi Ueda | 8fbf26a | 2009-01-06 03:05:06 +0000 | [diff] [blame] | 209 | goto out_free_rq_bio_info_cache; |
Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 210 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | _major = major; |
| 212 | r = register_blkdev(_major, _name); |
Kiyoshi Ueda | 51157b4 | 2008-10-21 17:45:08 +0100 | [diff] [blame] | 213 | if (r < 0) |
| 214 | goto out_uevent_exit; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | |
| 216 | if (!_major) |
| 217 | _major = r; |
| 218 | |
| 219 | return 0; |
Kiyoshi Ueda | 51157b4 | 2008-10-21 17:45:08 +0100 | [diff] [blame] | 220 | |
| 221 | out_uevent_exit: |
| 222 | dm_uevent_exit(); |
Kiyoshi Ueda | 8fbf26a | 2009-01-06 03:05:06 +0000 | [diff] [blame] | 223 | out_free_rq_bio_info_cache: |
| 224 | kmem_cache_destroy(_rq_bio_info_cache); |
| 225 | out_free_rq_tio_cache: |
| 226 | kmem_cache_destroy(_rq_tio_cache); |
Kiyoshi Ueda | 51157b4 | 2008-10-21 17:45:08 +0100 | [diff] [blame] | 227 | out_free_tio_cache: |
| 228 | kmem_cache_destroy(_tio_cache); |
| 229 | out_free_io_cache: |
| 230 | kmem_cache_destroy(_io_cache); |
| 231 | |
| 232 | return r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | } |
| 234 | |
| 235 | static void local_exit(void) |
| 236 | { |
Kiyoshi Ueda | 8fbf26a | 2009-01-06 03:05:06 +0000 | [diff] [blame] | 237 | kmem_cache_destroy(_rq_bio_info_cache); |
| 238 | kmem_cache_destroy(_rq_tio_cache); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | kmem_cache_destroy(_tio_cache); |
| 240 | kmem_cache_destroy(_io_cache); |
Akinobu Mita | 00d5940 | 2007-07-17 04:03:46 -0700 | [diff] [blame] | 241 | unregister_blkdev(_major, _name); |
Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 242 | dm_uevent_exit(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 243 | |
| 244 | _major = 0; |
| 245 | |
| 246 | DMINFO("cleaned up"); |
| 247 | } |
| 248 | |
Alasdair G Kergon | b9249e5 | 2008-02-08 02:09:51 +0000 | [diff] [blame] | 249 | static int (*_inits[])(void) __initdata = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | local_init, |
| 251 | dm_target_init, |
| 252 | dm_linear_init, |
| 253 | dm_stripe_init, |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 254 | dm_kcopyd_init, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | dm_interface_init, |
| 256 | }; |
| 257 | |
Alasdair G Kergon | b9249e5 | 2008-02-08 02:09:51 +0000 | [diff] [blame] | 258 | static void (*_exits[])(void) = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | local_exit, |
| 260 | dm_target_exit, |
| 261 | dm_linear_exit, |
| 262 | dm_stripe_exit, |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 263 | dm_kcopyd_exit, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | dm_interface_exit, |
| 265 | }; |
| 266 | |
| 267 | static int __init dm_init(void) |
| 268 | { |
| 269 | const int count = ARRAY_SIZE(_inits); |
| 270 | |
| 271 | int r, i; |
| 272 | |
| 273 | for (i = 0; i < count; i++) { |
| 274 | r = _inits[i](); |
| 275 | if (r) |
| 276 | goto bad; |
| 277 | } |
| 278 | |
| 279 | return 0; |
| 280 | |
| 281 | bad: |
| 282 | while (i--) |
| 283 | _exits[i](); |
| 284 | |
| 285 | return r; |
| 286 | } |
| 287 | |
| 288 | static void __exit dm_exit(void) |
| 289 | { |
| 290 | int i = ARRAY_SIZE(_exits); |
| 291 | |
| 292 | while (i--) |
| 293 | _exits[i](); |
| 294 | } |
| 295 | |
| 296 | /* |
| 297 | * Block device functions |
| 298 | */ |
Al Viro | fe5f9f2 | 2008-03-02 10:29:31 -0500 | [diff] [blame] | 299 | static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | { |
| 301 | struct mapped_device *md; |
| 302 | |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 303 | spin_lock(&_minor_lock); |
| 304 | |
Al Viro | fe5f9f2 | 2008-03-02 10:29:31 -0500 | [diff] [blame] | 305 | md = bdev->bd_disk->private_data; |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 306 | if (!md) |
| 307 | goto out; |
| 308 | |
Alasdair G Kergon | 5c6bd75 | 2006-06-26 00:27:34 -0700 | [diff] [blame] | 309 | if (test_bit(DMF_FREEING, &md->flags) || |
| 310 | test_bit(DMF_DELETING, &md->flags)) { |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 311 | md = NULL; |
| 312 | goto out; |
| 313 | } |
| 314 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 315 | dm_get(md); |
Alasdair G Kergon | 5c6bd75 | 2006-06-26 00:27:34 -0700 | [diff] [blame] | 316 | atomic_inc(&md->open_count); |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 317 | |
| 318 | out: |
| 319 | spin_unlock(&_minor_lock); |
| 320 | |
| 321 | return md ? 0 : -ENXIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | } |
| 323 | |
Al Viro | fe5f9f2 | 2008-03-02 10:29:31 -0500 | [diff] [blame] | 324 | static int dm_blk_close(struct gendisk *disk, fmode_t mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | { |
Al Viro | fe5f9f2 | 2008-03-02 10:29:31 -0500 | [diff] [blame] | 326 | struct mapped_device *md = disk->private_data; |
Alasdair G Kergon | 5c6bd75 | 2006-06-26 00:27:34 -0700 | [diff] [blame] | 327 | atomic_dec(&md->open_count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 328 | dm_put(md); |
| 329 | return 0; |
| 330 | } |
| 331 | |
Alasdair G Kergon | 5c6bd75 | 2006-06-26 00:27:34 -0700 | [diff] [blame] | 332 | int dm_open_count(struct mapped_device *md) |
| 333 | { |
| 334 | return atomic_read(&md->open_count); |
| 335 | } |
| 336 | |
| 337 | /* |
| 338 | * Guarantees nothing is using the device before it's deleted. |
| 339 | */ |
| 340 | int dm_lock_for_deletion(struct mapped_device *md) |
| 341 | { |
| 342 | int r = 0; |
| 343 | |
| 344 | spin_lock(&_minor_lock); |
| 345 | |
| 346 | if (dm_open_count(md)) |
| 347 | r = -EBUSY; |
| 348 | else |
| 349 | set_bit(DMF_DELETING, &md->flags); |
| 350 | |
| 351 | spin_unlock(&_minor_lock); |
| 352 | |
| 353 | return r; |
| 354 | } |
| 355 | |
Darrick J. Wong | 3ac51e7 | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 356 | static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
| 357 | { |
| 358 | struct mapped_device *md = bdev->bd_disk->private_data; |
| 359 | |
| 360 | return dm_get_geometry(md, geo); |
| 361 | } |
| 362 | |
Al Viro | fe5f9f2 | 2008-03-02 10:29:31 -0500 | [diff] [blame] | 363 | static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
Milan Broz | aa129a2 | 2006-10-03 01:15:15 -0700 | [diff] [blame] | 364 | unsigned int cmd, unsigned long arg) |
| 365 | { |
Al Viro | fe5f9f2 | 2008-03-02 10:29:31 -0500 | [diff] [blame] | 366 | struct mapped_device *md = bdev->bd_disk->private_data; |
| 367 | struct dm_table *map = dm_get_table(md); |
Milan Broz | aa129a2 | 2006-10-03 01:15:15 -0700 | [diff] [blame] | 368 | struct dm_target *tgt; |
| 369 | int r = -ENOTTY; |
| 370 | |
Milan Broz | aa129a2 | 2006-10-03 01:15:15 -0700 | [diff] [blame] | 371 | if (!map || !dm_table_get_size(map)) |
| 372 | goto out; |
| 373 | |
| 374 | /* We only support devices that have a single target */ |
| 375 | if (dm_table_get_num_targets(map) != 1) |
| 376 | goto out; |
| 377 | |
| 378 | tgt = dm_table_get_target(map, 0); |
| 379 | |
| 380 | if (dm_suspended(md)) { |
| 381 | r = -EAGAIN; |
| 382 | goto out; |
| 383 | } |
| 384 | |
| 385 | if (tgt->type->ioctl) |
Al Viro | 647b3d0 | 2007-08-28 22:15:59 -0400 | [diff] [blame] | 386 | r = tgt->type->ioctl(tgt, cmd, arg); |
Milan Broz | aa129a2 | 2006-10-03 01:15:15 -0700 | [diff] [blame] | 387 | |
| 388 | out: |
| 389 | dm_table_put(map); |
| 390 | |
Milan Broz | aa129a2 | 2006-10-03 01:15:15 -0700 | [diff] [blame] | 391 | return r; |
| 392 | } |
| 393 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 394 | static struct dm_io *alloc_io(struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | { |
| 396 | return mempool_alloc(md->io_pool, GFP_NOIO); |
| 397 | } |
| 398 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 399 | static void free_io(struct mapped_device *md, struct dm_io *io) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 400 | { |
| 401 | mempool_free(io, md->io_pool); |
| 402 | } |
| 403 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 404 | static void free_tio(struct mapped_device *md, struct dm_target_io *tio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 405 | { |
| 406 | mempool_free(tio, md->tio_pool); |
| 407 | } |
| 408 | |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 409 | static void start_io_acct(struct dm_io *io) |
| 410 | { |
| 411 | struct mapped_device *md = io->md; |
Tejun Heo | c995905 | 2008-08-25 19:47:21 +0900 | [diff] [blame] | 412 | int cpu; |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 413 | |
| 414 | io->start_time = jiffies; |
| 415 | |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 416 | cpu = part_stat_lock(); |
| 417 | part_round_stats(cpu, &dm_disk(md)->part0); |
| 418 | part_stat_unlock(); |
| 419 | dm_disk(md)->part0.in_flight = atomic_inc_return(&md->pending); |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 420 | } |
| 421 | |
Mikulas Patocka | d221d2e | 2008-11-13 23:39:10 +0000 | [diff] [blame] | 422 | static void end_io_acct(struct dm_io *io) |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 423 | { |
| 424 | struct mapped_device *md = io->md; |
| 425 | struct bio *bio = io->bio; |
| 426 | unsigned long duration = jiffies - io->start_time; |
Tejun Heo | c995905 | 2008-08-25 19:47:21 +0900 | [diff] [blame] | 427 | int pending, cpu; |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 428 | int rw = bio_data_dir(bio); |
| 429 | |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 430 | cpu = part_stat_lock(); |
| 431 | part_round_stats(cpu, &dm_disk(md)->part0); |
| 432 | part_stat_add(cpu, &dm_disk(md)->part0, ticks[rw], duration); |
| 433 | part_stat_unlock(); |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 434 | |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 435 | /* |
| 436 | * After this is decremented the bio must not be touched if it is |
| 437 | * a barrier. |
| 438 | */ |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 439 | dm_disk(md)->part0.in_flight = pending = |
| 440 | atomic_dec_return(&md->pending); |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 441 | |
Mikulas Patocka | d221d2e | 2008-11-13 23:39:10 +0000 | [diff] [blame] | 442 | /* nudge anyone waiting on suspend queue */ |
| 443 | if (!pending) |
| 444 | wake_up(&md->wait); |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 445 | } |
| 446 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | /* |
| 448 | * Add the bio to the list of deferred io. |
| 449 | */ |
Mikulas Patocka | 92c6390 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 450 | static void queue_io(struct mapped_device *md, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | { |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 452 | down_write(&md->io_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 453 | |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 454 | spin_lock_irq(&md->deferred_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | bio_list_add(&md->deferred, bio); |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 456 | spin_unlock_irq(&md->deferred_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | |
Mikulas Patocka | 92c6390 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 458 | if (!test_and_set_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags)) |
| 459 | queue_work(md->wq, &md->work); |
| 460 | |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 461 | up_write(&md->io_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | } |
| 463 | |
| 464 | /* |
| 465 | * Everyone (including functions in this file), should use this |
| 466 | * function to access the md->map field, and make sure they call |
| 467 | * dm_table_put() when finished. |
| 468 | */ |
| 469 | struct dm_table *dm_get_table(struct mapped_device *md) |
| 470 | { |
| 471 | struct dm_table *t; |
| 472 | |
| 473 | read_lock(&md->map_lock); |
| 474 | t = md->map; |
| 475 | if (t) |
| 476 | dm_table_get(t); |
| 477 | read_unlock(&md->map_lock); |
| 478 | |
| 479 | return t; |
| 480 | } |
| 481 | |
Darrick J. Wong | 3ac51e7 | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 482 | /* |
| 483 | * Get the geometry associated with a dm device |
| 484 | */ |
| 485 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) |
| 486 | { |
| 487 | *geo = md->geometry; |
| 488 | |
| 489 | return 0; |
| 490 | } |
| 491 | |
| 492 | /* |
| 493 | * Set the geometry of a device. |
| 494 | */ |
| 495 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) |
| 496 | { |
| 497 | sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; |
| 498 | |
| 499 | if (geo->start > sz) { |
| 500 | DMWARN("Start sector is beyond the geometry limits."); |
| 501 | return -EINVAL; |
| 502 | } |
| 503 | |
| 504 | md->geometry = *geo; |
| 505 | |
| 506 | return 0; |
| 507 | } |
| 508 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | /*----------------------------------------------------------------- |
| 510 | * CRUD START: |
| 511 | * A more elegant soln is in the works that uses the queue |
| 512 | * merge fn, unfortunately there are a couple of changes to |
| 513 | * the block layer that I want to make for this. So in the |
| 514 | * interests of getting something for people to use I give |
| 515 | * you this clearly demarcated crap. |
| 516 | *---------------------------------------------------------------*/ |
| 517 | |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 518 | static int __noflush_suspending(struct mapped_device *md) |
| 519 | { |
| 520 | return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
| 521 | } |
| 522 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | /* |
| 524 | * Decrements the number of outstanding ios that a bio has been |
| 525 | * cloned into, completing the original io if necc. |
| 526 | */ |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 527 | static void dec_pending(struct dm_io *io, int error) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 528 | { |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 529 | unsigned long flags; |
Milan Broz | b35f8ca | 2009-03-16 17:44:36 +0000 | [diff] [blame] | 530 | int io_error; |
| 531 | struct bio *bio; |
| 532 | struct mapped_device *md = io->md; |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 533 | |
| 534 | /* Push-back supersedes any I/O errors */ |
Milan Broz | b35f8ca | 2009-03-16 17:44:36 +0000 | [diff] [blame] | 535 | if (error && !(io->error > 0 && __noflush_suspending(md))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 536 | io->error = error; |
| 537 | |
| 538 | if (atomic_dec_and_test(&io->io_count)) { |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 539 | if (io->error == DM_ENDIO_REQUEUE) { |
| 540 | /* |
| 541 | * Target requested pushing back the I/O. |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 542 | */ |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 543 | spin_lock_irqsave(&md->deferred_lock, flags); |
Mikulas Patocka | 2761e95 | 2009-06-22 10:12:18 +0100 | [diff] [blame] | 544 | if (__noflush_suspending(md)) { |
| 545 | if (!bio_barrier(io->bio)) |
| 546 | bio_list_add_head(&md->deferred, |
| 547 | io->bio); |
| 548 | } else |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 549 | /* noflush suspend was interrupted. */ |
| 550 | io->error = -EIO; |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 551 | spin_unlock_irqrestore(&md->deferred_lock, flags); |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 552 | } |
| 553 | |
Milan Broz | b35f8ca | 2009-03-16 17:44:36 +0000 | [diff] [blame] | 554 | io_error = io->error; |
| 555 | bio = io->bio; |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 556 | |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 557 | if (bio_barrier(bio)) { |
| 558 | /* |
| 559 | * There can be just one barrier request so we use |
| 560 | * a per-device variable for error reporting. |
| 561 | * Note that you can't touch the bio after end_io_acct |
| 562 | */ |
Mikulas Patocka | fdb9572 | 2009-06-22 10:12:19 +0100 | [diff] [blame] | 563 | if (!md->barrier_error && io_error != -EOPNOTSUPP) |
Mikulas Patocka | 5aa2781 | 2009-06-22 10:12:18 +0100 | [diff] [blame] | 564 | md->barrier_error = io_error; |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 565 | end_io_acct(io); |
| 566 | } else { |
| 567 | end_io_acct(io); |
Milan Broz | b35f8ca | 2009-03-16 17:44:36 +0000 | [diff] [blame] | 568 | |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 569 | if (io_error != DM_ENDIO_REQUEUE) { |
| 570 | trace_block_bio_complete(md->queue, bio); |
Milan Broz | b35f8ca | 2009-03-16 17:44:36 +0000 | [diff] [blame] | 571 | |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 572 | bio_endio(bio, io_error); |
| 573 | } |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 574 | } |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 575 | |
| 576 | free_io(md, io); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | } |
| 578 | } |
| 579 | |
NeilBrown | 6712ecf | 2007-09-27 12:47:43 +0200 | [diff] [blame] | 580 | static void clone_endio(struct bio *bio, int error) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 581 | { |
| 582 | int r = 0; |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 583 | struct dm_target_io *tio = bio->bi_private; |
Milan Broz | b35f8ca | 2009-03-16 17:44:36 +0000 | [diff] [blame] | 584 | struct dm_io *io = tio->io; |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 585 | struct mapped_device *md = tio->io->md; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 586 | dm_endio_fn endio = tio->ti->type->end_io; |
| 587 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 588 | if (!bio_flagged(bio, BIO_UPTODATE) && !error) |
| 589 | error = -EIO; |
| 590 | |
| 591 | if (endio) { |
| 592 | r = endio(tio->ti, bio, error, &tio->info); |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 593 | if (r < 0 || r == DM_ENDIO_REQUEUE) |
| 594 | /* |
| 595 | * error and requeue request are handled |
| 596 | * in dec_pending(). |
| 597 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 598 | error = r; |
Kiyoshi Ueda | 45cbcd7 | 2006-12-08 02:41:05 -0800 | [diff] [blame] | 599 | else if (r == DM_ENDIO_INCOMPLETE) |
| 600 | /* The target will handle the io */ |
NeilBrown | 6712ecf | 2007-09-27 12:47:43 +0200 | [diff] [blame] | 601 | return; |
Kiyoshi Ueda | 45cbcd7 | 2006-12-08 02:41:05 -0800 | [diff] [blame] | 602 | else if (r) { |
| 603 | DMWARN("unimplemented target endio return value: %d", r); |
| 604 | BUG(); |
| 605 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 606 | } |
| 607 | |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 608 | /* |
| 609 | * Store md for cleanup instead of tio which is about to get freed. |
| 610 | */ |
| 611 | bio->bi_private = md->bs; |
| 612 | |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 613 | free_tio(md, tio); |
Milan Broz | b35f8ca | 2009-03-16 17:44:36 +0000 | [diff] [blame] | 614 | bio_put(bio); |
| 615 | dec_pending(io, error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | } |
| 617 | |
| 618 | static sector_t max_io_len(struct mapped_device *md, |
| 619 | sector_t sector, struct dm_target *ti) |
| 620 | { |
| 621 | sector_t offset = sector - ti->begin; |
| 622 | sector_t len = ti->len - offset; |
| 623 | |
| 624 | /* |
| 625 | * Does the target need to split even further ? |
| 626 | */ |
| 627 | if (ti->split_io) { |
| 628 | sector_t boundary; |
| 629 | boundary = ((offset + ti->split_io) & ~(ti->split_io - 1)) |
| 630 | - offset; |
| 631 | if (len > boundary) |
| 632 | len = boundary; |
| 633 | } |
| 634 | |
| 635 | return len; |
| 636 | } |
| 637 | |
| 638 | static void __map_bio(struct dm_target *ti, struct bio *clone, |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 639 | struct dm_target_io *tio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 640 | { |
| 641 | int r; |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 642 | sector_t sector; |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 643 | struct mapped_device *md; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 644 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 645 | clone->bi_end_io = clone_endio; |
| 646 | clone->bi_private = tio; |
| 647 | |
| 648 | /* |
| 649 | * Map the clone. If r == 0 we don't need to do |
| 650 | * anything, the target has assumed ownership of |
| 651 | * this io. |
| 652 | */ |
| 653 | atomic_inc(&tio->io->io_count); |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 654 | sector = clone->bi_sector; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | r = ti->type->map(ti, clone, &tio->info); |
Kiyoshi Ueda | 45cbcd7 | 2006-12-08 02:41:05 -0800 | [diff] [blame] | 656 | if (r == DM_MAPIO_REMAPPED) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | /* the bio has been remapped so dispatch it */ |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 658 | |
Arnaldo Carvalho de Melo | 5f3ea37 | 2008-10-30 08:34:33 +0100 | [diff] [blame] | 659 | trace_block_remap(bdev_get_queue(clone->bi_bdev), clone, |
Alan D. Brunelle | 22a7c31 | 2009-05-04 16:35:08 -0400 | [diff] [blame] | 660 | tio->io->bio->bi_bdev->bd_dev, sector); |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 661 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 662 | generic_make_request(clone); |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 663 | } else if (r < 0 || r == DM_MAPIO_REQUEUE) { |
| 664 | /* error the io and bail out, or requeue it if needed */ |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 665 | md = tio->io->md; |
| 666 | dec_pending(tio->io, r); |
| 667 | /* |
| 668 | * Store bio_set for cleanup. |
| 669 | */ |
| 670 | clone->bi_private = md->bs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | bio_put(clone); |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 672 | free_tio(md, tio); |
Kiyoshi Ueda | 45cbcd7 | 2006-12-08 02:41:05 -0800 | [diff] [blame] | 673 | } else if (r) { |
| 674 | DMWARN("unimplemented target map return value: %d", r); |
| 675 | BUG(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 676 | } |
| 677 | } |
| 678 | |
| 679 | struct clone_info { |
| 680 | struct mapped_device *md; |
| 681 | struct dm_table *map; |
| 682 | struct bio *bio; |
| 683 | struct dm_io *io; |
| 684 | sector_t sector; |
| 685 | sector_t sector_count; |
| 686 | unsigned short idx; |
| 687 | }; |
| 688 | |
Peter Osterlund | 3676347 | 2005-09-06 15:16:42 -0700 | [diff] [blame] | 689 | static void dm_bio_destructor(struct bio *bio) |
| 690 | { |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 691 | struct bio_set *bs = bio->bi_private; |
| 692 | |
| 693 | bio_free(bio, bs); |
Peter Osterlund | 3676347 | 2005-09-06 15:16:42 -0700 | [diff] [blame] | 694 | } |
| 695 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | /* |
| 697 | * Creates a little bio that is just does part of a bvec. |
| 698 | */ |
| 699 | static struct bio *split_bvec(struct bio *bio, sector_t sector, |
| 700 | unsigned short idx, unsigned int offset, |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 701 | unsigned int len, struct bio_set *bs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | { |
| 703 | struct bio *clone; |
| 704 | struct bio_vec *bv = bio->bi_io_vec + idx; |
| 705 | |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 706 | clone = bio_alloc_bioset(GFP_NOIO, 1, bs); |
Peter Osterlund | 3676347 | 2005-09-06 15:16:42 -0700 | [diff] [blame] | 707 | clone->bi_destructor = dm_bio_destructor; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | *clone->bi_io_vec = *bv; |
| 709 | |
| 710 | clone->bi_sector = sector; |
| 711 | clone->bi_bdev = bio->bi_bdev; |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 712 | clone->bi_rw = bio->bi_rw & ~(1 << BIO_RW_BARRIER); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | clone->bi_vcnt = 1; |
| 714 | clone->bi_size = to_bytes(len); |
| 715 | clone->bi_io_vec->bv_offset = offset; |
| 716 | clone->bi_io_vec->bv_len = clone->bi_size; |
Martin K. Petersen | f3e1d26 | 2008-10-21 17:45:04 +0100 | [diff] [blame] | 717 | clone->bi_flags |= 1 << BIO_CLONED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 718 | |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 719 | if (bio_integrity(bio)) { |
| 720 | bio_integrity_clone(clone, bio, GFP_NOIO); |
| 721 | bio_integrity_trim(clone, |
| 722 | bio_sector_offset(bio, idx, offset), len); |
| 723 | } |
| 724 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 725 | return clone; |
| 726 | } |
| 727 | |
| 728 | /* |
| 729 | * Creates a bio that consists of range of complete bvecs. |
| 730 | */ |
| 731 | static struct bio *clone_bio(struct bio *bio, sector_t sector, |
| 732 | unsigned short idx, unsigned short bv_count, |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 733 | unsigned int len, struct bio_set *bs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 734 | { |
| 735 | struct bio *clone; |
| 736 | |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 737 | clone = bio_alloc_bioset(GFP_NOIO, bio->bi_max_vecs, bs); |
| 738 | __bio_clone(clone, bio); |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 739 | clone->bi_rw &= ~(1 << BIO_RW_BARRIER); |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 740 | clone->bi_destructor = dm_bio_destructor; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 741 | clone->bi_sector = sector; |
| 742 | clone->bi_idx = idx; |
| 743 | clone->bi_vcnt = idx + bv_count; |
| 744 | clone->bi_size = to_bytes(len); |
| 745 | clone->bi_flags &= ~(1 << BIO_SEG_VALID); |
| 746 | |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 747 | if (bio_integrity(bio)) { |
| 748 | bio_integrity_clone(clone, bio, GFP_NOIO); |
| 749 | |
| 750 | if (idx != bio->bi_idx || clone->bi_size < bio->bi_size) |
| 751 | bio_integrity_trim(clone, |
| 752 | bio_sector_offset(bio, idx, 0), len); |
| 753 | } |
| 754 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 755 | return clone; |
| 756 | } |
| 757 | |
Alasdair G Kergon | 9015df2 | 2009-06-22 10:12:21 +0100 | [diff] [blame] | 758 | static struct dm_target_io *alloc_tio(struct clone_info *ci, |
| 759 | struct dm_target *ti) |
Mikulas Patocka | f9ab94c | 2009-06-22 10:12:20 +0100 | [diff] [blame] | 760 | { |
Alasdair G Kergon | 9015df2 | 2009-06-22 10:12:21 +0100 | [diff] [blame] | 761 | struct dm_target_io *tio = mempool_alloc(ci->md->tio_pool, GFP_NOIO); |
Mikulas Patocka | f9ab94c | 2009-06-22 10:12:20 +0100 | [diff] [blame] | 762 | |
| 763 | tio->io = ci->io; |
| 764 | tio->ti = ti; |
Mikulas Patocka | f9ab94c | 2009-06-22 10:12:20 +0100 | [diff] [blame] | 765 | memset(&tio->info, 0, sizeof(tio->info)); |
Alasdair G Kergon | 9015df2 | 2009-06-22 10:12:21 +0100 | [diff] [blame] | 766 | |
| 767 | return tio; |
| 768 | } |
| 769 | |
| 770 | static void __flush_target(struct clone_info *ci, struct dm_target *ti, |
| 771 | unsigned flush_nr) |
| 772 | { |
| 773 | struct dm_target_io *tio = alloc_tio(ci, ti); |
| 774 | struct bio *clone; |
| 775 | |
Mikulas Patocka | f9ab94c | 2009-06-22 10:12:20 +0100 | [diff] [blame] | 776 | tio->info.flush_request = flush_nr; |
| 777 | |
| 778 | clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs); |
| 779 | __bio_clone(clone, ci->bio); |
| 780 | clone->bi_destructor = dm_bio_destructor; |
| 781 | |
| 782 | __map_bio(ti, clone, tio); |
| 783 | } |
| 784 | |
| 785 | static int __clone_and_map_empty_barrier(struct clone_info *ci) |
| 786 | { |
| 787 | unsigned target_nr = 0, flush_nr; |
| 788 | struct dm_target *ti; |
| 789 | |
| 790 | while ((ti = dm_table_get_target(ci->map, target_nr++))) |
| 791 | for (flush_nr = 0; flush_nr < ti->num_flush_requests; |
| 792 | flush_nr++) |
| 793 | __flush_target(ci, ti, flush_nr); |
| 794 | |
| 795 | ci->sector_count = 0; |
| 796 | |
| 797 | return 0; |
| 798 | } |
| 799 | |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 800 | static int __clone_and_map(struct clone_info *ci) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 801 | { |
| 802 | struct bio *clone, *bio = ci->bio; |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 803 | struct dm_target *ti; |
| 804 | sector_t len = 0, max; |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 805 | struct dm_target_io *tio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 806 | |
Mikulas Patocka | f9ab94c | 2009-06-22 10:12:20 +0100 | [diff] [blame] | 807 | if (unlikely(bio_empty_barrier(bio))) |
| 808 | return __clone_and_map_empty_barrier(ci); |
| 809 | |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 810 | ti = dm_table_find_target(ci->map, ci->sector); |
| 811 | if (!dm_target_is_valid(ti)) |
| 812 | return -EIO; |
| 813 | |
| 814 | max = max_io_len(ci->md, ci->sector, ti); |
| 815 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | /* |
| 817 | * Allocate a target io object. |
| 818 | */ |
Alasdair G Kergon | 9015df2 | 2009-06-22 10:12:21 +0100 | [diff] [blame] | 819 | tio = alloc_tio(ci, ti); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | |
| 821 | if (ci->sector_count <= max) { |
| 822 | /* |
| 823 | * Optimise for the simple case where we can do all of |
| 824 | * the remaining io with a single clone. |
| 825 | */ |
| 826 | clone = clone_bio(bio, ci->sector, ci->idx, |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 827 | bio->bi_vcnt - ci->idx, ci->sector_count, |
| 828 | ci->md->bs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 829 | __map_bio(ti, clone, tio); |
| 830 | ci->sector_count = 0; |
| 831 | |
| 832 | } else if (to_sector(bio->bi_io_vec[ci->idx].bv_len) <= max) { |
| 833 | /* |
| 834 | * There are some bvecs that don't span targets. |
| 835 | * Do as many of these as possible. |
| 836 | */ |
| 837 | int i; |
| 838 | sector_t remaining = max; |
| 839 | sector_t bv_len; |
| 840 | |
| 841 | for (i = ci->idx; remaining && (i < bio->bi_vcnt); i++) { |
| 842 | bv_len = to_sector(bio->bi_io_vec[i].bv_len); |
| 843 | |
| 844 | if (bv_len > remaining) |
| 845 | break; |
| 846 | |
| 847 | remaining -= bv_len; |
| 848 | len += bv_len; |
| 849 | } |
| 850 | |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 851 | clone = clone_bio(bio, ci->sector, ci->idx, i - ci->idx, len, |
| 852 | ci->md->bs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | __map_bio(ti, clone, tio); |
| 854 | |
| 855 | ci->sector += len; |
| 856 | ci->sector_count -= len; |
| 857 | ci->idx = i; |
| 858 | |
| 859 | } else { |
| 860 | /* |
Alasdair G Kergon | d2044a9 | 2006-03-22 00:07:42 -0800 | [diff] [blame] | 861 | * Handle a bvec that must be split between two or more targets. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 862 | */ |
| 863 | struct bio_vec *bv = bio->bi_io_vec + ci->idx; |
Alasdair G Kergon | d2044a9 | 2006-03-22 00:07:42 -0800 | [diff] [blame] | 864 | sector_t remaining = to_sector(bv->bv_len); |
| 865 | unsigned int offset = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 866 | |
Alasdair G Kergon | d2044a9 | 2006-03-22 00:07:42 -0800 | [diff] [blame] | 867 | do { |
| 868 | if (offset) { |
| 869 | ti = dm_table_find_target(ci->map, ci->sector); |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 870 | if (!dm_target_is_valid(ti)) |
| 871 | return -EIO; |
| 872 | |
Alasdair G Kergon | d2044a9 | 2006-03-22 00:07:42 -0800 | [diff] [blame] | 873 | max = max_io_len(ci->md, ci->sector, ti); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 874 | |
Alasdair G Kergon | 9015df2 | 2009-06-22 10:12:21 +0100 | [diff] [blame] | 875 | tio = alloc_tio(ci, ti); |
Alasdair G Kergon | d2044a9 | 2006-03-22 00:07:42 -0800 | [diff] [blame] | 876 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 877 | |
Alasdair G Kergon | d2044a9 | 2006-03-22 00:07:42 -0800 | [diff] [blame] | 878 | len = min(remaining, max); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 879 | |
Alasdair G Kergon | d2044a9 | 2006-03-22 00:07:42 -0800 | [diff] [blame] | 880 | clone = split_bvec(bio, ci->sector, ci->idx, |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 881 | bv->bv_offset + offset, len, |
| 882 | ci->md->bs); |
Alasdair G Kergon | d2044a9 | 2006-03-22 00:07:42 -0800 | [diff] [blame] | 883 | |
| 884 | __map_bio(ti, clone, tio); |
| 885 | |
| 886 | ci->sector += len; |
| 887 | ci->sector_count -= len; |
| 888 | offset += to_bytes(len); |
| 889 | } while (remaining -= len); |
| 890 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 891 | ci->idx++; |
| 892 | } |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 893 | |
| 894 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | } |
| 896 | |
| 897 | /* |
Mikulas Patocka | 8a53c28 | 2009-04-02 19:55:37 +0100 | [diff] [blame] | 898 | * Split the bio into several clones and submit it to targets. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 899 | */ |
Mikulas Patocka | f0b9a45 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 900 | static void __split_and_process_bio(struct mapped_device *md, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 901 | { |
| 902 | struct clone_info ci; |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 903 | int error = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 904 | |
| 905 | ci.map = dm_get_table(md); |
Mikulas Patocka | f0b9a45 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 906 | if (unlikely(!ci.map)) { |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 907 | if (!bio_barrier(bio)) |
| 908 | bio_io_error(bio); |
| 909 | else |
Mikulas Patocka | 5aa2781 | 2009-06-22 10:12:18 +0100 | [diff] [blame] | 910 | if (!md->barrier_error) |
| 911 | md->barrier_error = -EIO; |
Mikulas Patocka | f0b9a45 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 912 | return; |
| 913 | } |
Mikulas Patocka | 692d0eb | 2009-04-09 00:27:13 +0100 | [diff] [blame] | 914 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 915 | ci.md = md; |
| 916 | ci.bio = bio; |
| 917 | ci.io = alloc_io(md); |
| 918 | ci.io->error = 0; |
| 919 | atomic_set(&ci.io->io_count, 1); |
| 920 | ci.io->bio = bio; |
| 921 | ci.io->md = md; |
| 922 | ci.sector = bio->bi_sector; |
| 923 | ci.sector_count = bio_sectors(bio); |
Mikulas Patocka | f9ab94c | 2009-06-22 10:12:20 +0100 | [diff] [blame] | 924 | if (unlikely(bio_empty_barrier(bio))) |
| 925 | ci.sector_count = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 926 | ci.idx = bio->bi_idx; |
| 927 | |
Jun'ichi "Nick" Nomura | 3eaf840 | 2006-02-01 03:04:53 -0800 | [diff] [blame] | 928 | start_io_acct(ci.io); |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 929 | while (ci.sector_count && !error) |
| 930 | error = __clone_and_map(&ci); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | |
| 932 | /* drop the extra reference count */ |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 933 | dec_pending(ci.io, error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 934 | dm_table_put(ci.map); |
| 935 | } |
| 936 | /*----------------------------------------------------------------- |
| 937 | * CRUD END |
| 938 | *---------------------------------------------------------------*/ |
| 939 | |
Milan Broz | f6fccb1 | 2008-07-21 12:00:37 +0100 | [diff] [blame] | 940 | static int dm_merge_bvec(struct request_queue *q, |
| 941 | struct bvec_merge_data *bvm, |
| 942 | struct bio_vec *biovec) |
| 943 | { |
| 944 | struct mapped_device *md = q->queuedata; |
| 945 | struct dm_table *map = dm_get_table(md); |
| 946 | struct dm_target *ti; |
| 947 | sector_t max_sectors; |
Mikulas Patocka | 5037108 | 2008-10-01 14:39:17 +0100 | [diff] [blame] | 948 | int max_size = 0; |
Milan Broz | f6fccb1 | 2008-07-21 12:00:37 +0100 | [diff] [blame] | 949 | |
| 950 | if (unlikely(!map)) |
Mikulas Patocka | 5037108 | 2008-10-01 14:39:17 +0100 | [diff] [blame] | 951 | goto out; |
Milan Broz | f6fccb1 | 2008-07-21 12:00:37 +0100 | [diff] [blame] | 952 | |
| 953 | ti = dm_table_find_target(map, bvm->bi_sector); |
Mikulas Patocka | b01cd5a | 2008-10-01 14:39:24 +0100 | [diff] [blame] | 954 | if (!dm_target_is_valid(ti)) |
| 955 | goto out_table; |
Milan Broz | f6fccb1 | 2008-07-21 12:00:37 +0100 | [diff] [blame] | 956 | |
| 957 | /* |
| 958 | * Find maximum amount of I/O that won't need splitting |
| 959 | */ |
| 960 | max_sectors = min(max_io_len(md, bvm->bi_sector, ti), |
| 961 | (sector_t) BIO_MAX_SECTORS); |
| 962 | max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size; |
| 963 | if (max_size < 0) |
| 964 | max_size = 0; |
| 965 | |
| 966 | /* |
| 967 | * merge_bvec_fn() returns number of bytes |
| 968 | * it can accept at this offset |
| 969 | * max is precomputed maximal io size |
| 970 | */ |
| 971 | if (max_size && ti->type->merge) |
| 972 | max_size = ti->type->merge(ti, bvm, biovec, max_size); |
Mikulas Patocka | 8cbeb67 | 2009-06-22 10:12:14 +0100 | [diff] [blame] | 973 | /* |
| 974 | * If the target doesn't support merge method and some of the devices |
| 975 | * provided their merge_bvec method (we know this by looking at |
| 976 | * queue_max_hw_sectors), then we can't allow bios with multiple vector |
| 977 | * entries. So always set max_size to 0, and the code below allows |
| 978 | * just one page. |
| 979 | */ |
| 980 | else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9) |
| 981 | |
| 982 | max_size = 0; |
Milan Broz | f6fccb1 | 2008-07-21 12:00:37 +0100 | [diff] [blame] | 983 | |
Mikulas Patocka | b01cd5a | 2008-10-01 14:39:24 +0100 | [diff] [blame] | 984 | out_table: |
Mikulas Patocka | 5037108 | 2008-10-01 14:39:17 +0100 | [diff] [blame] | 985 | dm_table_put(map); |
| 986 | |
| 987 | out: |
Milan Broz | f6fccb1 | 2008-07-21 12:00:37 +0100 | [diff] [blame] | 988 | /* |
| 989 | * Always allow an entire first page |
| 990 | */ |
| 991 | if (max_size <= biovec->bv_len && !(bvm->bi_size >> SECTOR_SHIFT)) |
| 992 | max_size = biovec->bv_len; |
| 993 | |
Milan Broz | f6fccb1 | 2008-07-21 12:00:37 +0100 | [diff] [blame] | 994 | return max_size; |
| 995 | } |
| 996 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 997 | /* |
| 998 | * The request function that just remaps the bio built up by |
| 999 | * dm_merge_bvec. |
| 1000 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1001 | static int dm_request(struct request_queue *q, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1002 | { |
Kevin Corry | 12f03a4 | 2006-02-01 03:04:52 -0800 | [diff] [blame] | 1003 | int rw = bio_data_dir(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1004 | struct mapped_device *md = q->queuedata; |
Tejun Heo | c995905 | 2008-08-25 19:47:21 +0900 | [diff] [blame] | 1005 | int cpu; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1006 | |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1007 | down_read(&md->io_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1008 | |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 1009 | cpu = part_stat_lock(); |
| 1010 | part_stat_inc(cpu, &dm_disk(md)->part0, ios[rw]); |
| 1011 | part_stat_add(cpu, &dm_disk(md)->part0, sectors[rw], bio_sectors(bio)); |
| 1012 | part_stat_unlock(); |
Kevin Corry | 12f03a4 | 2006-02-01 03:04:52 -0800 | [diff] [blame] | 1013 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1014 | /* |
Alasdair G Kergon | 1eb787e | 2009-04-09 00:27:14 +0100 | [diff] [blame] | 1015 | * If we're suspended or the thread is processing barriers |
| 1016 | * we have to queue this io for later. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1017 | */ |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 1018 | if (unlikely(test_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags)) || |
| 1019 | unlikely(bio_barrier(bio))) { |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1020 | up_read(&md->io_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1021 | |
Alasdair G Kergon | 54d9a1b | 2009-04-09 00:27:14 +0100 | [diff] [blame] | 1022 | if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) && |
| 1023 | bio_rw(bio) == READA) { |
| 1024 | bio_io_error(bio); |
| 1025 | return 0; |
| 1026 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1027 | |
Mikulas Patocka | 92c6390 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1028 | queue_io(md, bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1029 | |
Mikulas Patocka | 92c6390 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1030 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1031 | } |
| 1032 | |
Mikulas Patocka | f0b9a45 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1033 | __split_and_process_bio(md, bio); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1034 | up_read(&md->io_lock); |
Mikulas Patocka | f0b9a45 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1035 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1036 | } |
| 1037 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1038 | static void dm_unplug_all(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1039 | { |
| 1040 | struct mapped_device *md = q->queuedata; |
| 1041 | struct dm_table *map = dm_get_table(md); |
| 1042 | |
| 1043 | if (map) { |
| 1044 | dm_table_unplug_all(map); |
| 1045 | dm_table_put(map); |
| 1046 | } |
| 1047 | } |
| 1048 | |
| 1049 | static int dm_any_congested(void *congested_data, int bdi_bits) |
| 1050 | { |
Chandra Seetharaman | 8a57dfc | 2008-11-13 23:39:14 +0000 | [diff] [blame] | 1051 | int r = bdi_bits; |
| 1052 | struct mapped_device *md = congested_data; |
| 1053 | struct dm_table *map; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1054 | |
Alasdair G Kergon | 1eb787e | 2009-04-09 00:27:14 +0100 | [diff] [blame] | 1055 | if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
Chandra Seetharaman | 8a57dfc | 2008-11-13 23:39:14 +0000 | [diff] [blame] | 1056 | map = dm_get_table(md); |
| 1057 | if (map) { |
| 1058 | r = dm_table_any_congested(map, bdi_bits); |
| 1059 | dm_table_put(map); |
| 1060 | } |
| 1061 | } |
| 1062 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1063 | return r; |
| 1064 | } |
| 1065 | |
| 1066 | /*----------------------------------------------------------------- |
| 1067 | * An IDR is used to keep track of allocated minor numbers. |
| 1068 | *---------------------------------------------------------------*/ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1069 | static DEFINE_IDR(_minor_idr); |
| 1070 | |
Alasdair G Kergon | 2b06cff | 2006-06-26 00:27:32 -0700 | [diff] [blame] | 1071 | static void free_minor(int minor) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1072 | { |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1073 | spin_lock(&_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1074 | idr_remove(&_minor_idr, minor); |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1075 | spin_unlock(&_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1076 | } |
| 1077 | |
| 1078 | /* |
| 1079 | * See if the device with a specific minor # is free. |
| 1080 | */ |
Frederik Deweerdt | cf13ab8 | 2008-04-24 22:10:59 +0100 | [diff] [blame] | 1081 | static int specific_minor(int minor) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1082 | { |
| 1083 | int r, m; |
| 1084 | |
| 1085 | if (minor >= (1 << MINORBITS)) |
| 1086 | return -EINVAL; |
| 1087 | |
Jeff Mahoney | 62f75c2 | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1088 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
| 1089 | if (!r) |
| 1090 | return -ENOMEM; |
| 1091 | |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1092 | spin_lock(&_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1093 | |
| 1094 | if (idr_find(&_minor_idr, minor)) { |
| 1095 | r = -EBUSY; |
| 1096 | goto out; |
| 1097 | } |
| 1098 | |
Jeff Mahoney | ba61fdd | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1099 | r = idr_get_new_above(&_minor_idr, MINOR_ALLOCED, minor, &m); |
Jeff Mahoney | 62f75c2 | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1100 | if (r) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1101 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1102 | |
| 1103 | if (m != minor) { |
| 1104 | idr_remove(&_minor_idr, m); |
| 1105 | r = -EBUSY; |
| 1106 | goto out; |
| 1107 | } |
| 1108 | |
| 1109 | out: |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1110 | spin_unlock(&_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1111 | return r; |
| 1112 | } |
| 1113 | |
Frederik Deweerdt | cf13ab8 | 2008-04-24 22:10:59 +0100 | [diff] [blame] | 1114 | static int next_free_minor(int *minor) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1115 | { |
Alasdair G Kergon | 2b06cff | 2006-06-26 00:27:32 -0700 | [diff] [blame] | 1116 | int r, m; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1117 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1118 | r = idr_pre_get(&_minor_idr, GFP_KERNEL); |
Jeff Mahoney | 62f75c2 | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1119 | if (!r) |
| 1120 | return -ENOMEM; |
| 1121 | |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1122 | spin_lock(&_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1123 | |
Jeff Mahoney | ba61fdd | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1124 | r = idr_get_new(&_minor_idr, MINOR_ALLOCED, &m); |
Frederik Deweerdt | cf13ab8 | 2008-04-24 22:10:59 +0100 | [diff] [blame] | 1125 | if (r) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1126 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1127 | |
| 1128 | if (m >= (1 << MINORBITS)) { |
| 1129 | idr_remove(&_minor_idr, m); |
| 1130 | r = -ENOSPC; |
| 1131 | goto out; |
| 1132 | } |
| 1133 | |
| 1134 | *minor = m; |
| 1135 | |
| 1136 | out: |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1137 | spin_unlock(&_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1138 | return r; |
| 1139 | } |
| 1140 | |
| 1141 | static struct block_device_operations dm_blk_dops; |
| 1142 | |
Mikulas Patocka | 53d5914 | 2009-04-02 19:55:37 +0100 | [diff] [blame] | 1143 | static void dm_wq_work(struct work_struct *work); |
| 1144 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1145 | /* |
| 1146 | * Allocate and initialise a blank device with a given minor. |
| 1147 | */ |
Alasdair G Kergon | 2b06cff | 2006-06-26 00:27:32 -0700 | [diff] [blame] | 1148 | static struct mapped_device *alloc_dev(int minor) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1149 | { |
| 1150 | int r; |
Frederik Deweerdt | cf13ab8 | 2008-04-24 22:10:59 +0100 | [diff] [blame] | 1151 | struct mapped_device *md = kzalloc(sizeof(*md), GFP_KERNEL); |
Jeff Mahoney | ba61fdd | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1152 | void *old_md; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1153 | |
| 1154 | if (!md) { |
| 1155 | DMWARN("unable to allocate device, out of memory."); |
| 1156 | return NULL; |
| 1157 | } |
| 1158 | |
Jeff Mahoney | 10da4f7 | 2006-06-26 00:27:25 -0700 | [diff] [blame] | 1159 | if (!try_module_get(THIS_MODULE)) |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1160 | goto bad_module_get; |
Jeff Mahoney | 10da4f7 | 2006-06-26 00:27:25 -0700 | [diff] [blame] | 1161 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1162 | /* get a minor number for the dev */ |
Alasdair G Kergon | 2b06cff | 2006-06-26 00:27:32 -0700 | [diff] [blame] | 1163 | if (minor == DM_ANY_MINOR) |
Frederik Deweerdt | cf13ab8 | 2008-04-24 22:10:59 +0100 | [diff] [blame] | 1164 | r = next_free_minor(&minor); |
Alasdair G Kergon | 2b06cff | 2006-06-26 00:27:32 -0700 | [diff] [blame] | 1165 | else |
Frederik Deweerdt | cf13ab8 | 2008-04-24 22:10:59 +0100 | [diff] [blame] | 1166 | r = specific_minor(minor); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1167 | if (r < 0) |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1168 | goto bad_minor; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1169 | |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1170 | init_rwsem(&md->io_lock); |
Daniel Walker | e61290a | 2008-02-08 02:10:08 +0000 | [diff] [blame] | 1171 | mutex_init(&md->suspend_lock); |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 1172 | spin_lock_init(&md->deferred_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1173 | rwlock_init(&md->map_lock); |
| 1174 | atomic_set(&md->holders, 1); |
Alasdair G Kergon | 5c6bd75 | 2006-06-26 00:27:34 -0700 | [diff] [blame] | 1175 | atomic_set(&md->open_count, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1176 | atomic_set(&md->event_nr, 0); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 1177 | atomic_set(&md->uevent_seq, 0); |
| 1178 | INIT_LIST_HEAD(&md->uevent_list); |
| 1179 | spin_lock_init(&md->uevent_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1180 | |
| 1181 | md->queue = blk_alloc_queue(GFP_KERNEL); |
| 1182 | if (!md->queue) |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1183 | goto bad_queue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1184 | |
| 1185 | md->queue->queuedata = md; |
| 1186 | md->queue->backing_dev_info.congested_fn = dm_any_congested; |
| 1187 | md->queue->backing_dev_info.congested_data = md; |
| 1188 | blk_queue_make_request(md->queue, dm_request); |
Mikulas Patocka | 99360b4 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 1189 | blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN, NULL); |
Jens Axboe | daef265 | 2006-01-10 10:48:02 +0100 | [diff] [blame] | 1190 | blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1191 | md->queue->unplug_fn = dm_unplug_all; |
Milan Broz | f6fccb1 | 2008-07-21 12:00:37 +0100 | [diff] [blame] | 1192 | blk_queue_merge_bvec(md->queue, dm_merge_bvec); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1193 | |
Matthew Dobson | 93d2341 | 2006-03-26 01:37:50 -0800 | [diff] [blame] | 1194 | md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache); |
Kiyoshi Ueda | 7485936 | 2006-12-08 02:41:02 -0800 | [diff] [blame] | 1195 | if (!md->io_pool) |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1196 | goto bad_io_pool; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1197 | |
Matthew Dobson | 93d2341 | 2006-03-26 01:37:50 -0800 | [diff] [blame] | 1198 | md->tio_pool = mempool_create_slab_pool(MIN_IOS, _tio_cache); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1199 | if (!md->tio_pool) |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1200 | goto bad_tio_pool; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1201 | |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 1202 | md->bs = bioset_create(16, 0); |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 1203 | if (!md->bs) |
| 1204 | goto bad_no_bioset; |
| 1205 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1206 | md->disk = alloc_disk(1); |
| 1207 | if (!md->disk) |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1208 | goto bad_disk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1209 | |
Jeff Mahoney | f0b0411 | 2006-06-26 00:27:25 -0700 | [diff] [blame] | 1210 | atomic_set(&md->pending, 0); |
| 1211 | init_waitqueue_head(&md->wait); |
Mikulas Patocka | 53d5914 | 2009-04-02 19:55:37 +0100 | [diff] [blame] | 1212 | INIT_WORK(&md->work, dm_wq_work); |
Jeff Mahoney | f0b0411 | 2006-06-26 00:27:25 -0700 | [diff] [blame] | 1213 | init_waitqueue_head(&md->eventq); |
| 1214 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1215 | md->disk->major = _major; |
| 1216 | md->disk->first_minor = minor; |
| 1217 | md->disk->fops = &dm_blk_dops; |
| 1218 | md->disk->queue = md->queue; |
| 1219 | md->disk->private_data = md; |
| 1220 | sprintf(md->disk->disk_name, "dm-%d", minor); |
| 1221 | add_disk(md->disk); |
Mike Anderson | 7e51f25 | 2006-03-27 01:17:52 -0800 | [diff] [blame] | 1222 | format_dev_t(md->name, MKDEV(_major, minor)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1223 | |
Milan Broz | 304f3f6 | 2008-02-08 02:11:17 +0000 | [diff] [blame] | 1224 | md->wq = create_singlethread_workqueue("kdmflush"); |
| 1225 | if (!md->wq) |
| 1226 | goto bad_thread; |
| 1227 | |
Mikulas Patocka | 32a926d | 2009-06-22 10:12:17 +0100 | [diff] [blame] | 1228 | md->bdev = bdget_disk(md->disk, 0); |
| 1229 | if (!md->bdev) |
| 1230 | goto bad_bdev; |
| 1231 | |
Jeff Mahoney | ba61fdd | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1232 | /* Populate the mapping, nobody knows we exist yet */ |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1233 | spin_lock(&_minor_lock); |
Jeff Mahoney | ba61fdd | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1234 | old_md = idr_replace(&_minor_idr, md, minor); |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1235 | spin_unlock(&_minor_lock); |
Jeff Mahoney | ba61fdd | 2006-06-26 00:27:21 -0700 | [diff] [blame] | 1236 | |
| 1237 | BUG_ON(old_md != MINOR_ALLOCED); |
| 1238 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1239 | return md; |
| 1240 | |
Mikulas Patocka | 32a926d | 2009-06-22 10:12:17 +0100 | [diff] [blame] | 1241 | bad_bdev: |
| 1242 | destroy_workqueue(md->wq); |
Milan Broz | 304f3f6 | 2008-02-08 02:11:17 +0000 | [diff] [blame] | 1243 | bad_thread: |
| 1244 | put_disk(md->disk); |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1245 | bad_disk: |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 1246 | bioset_free(md->bs); |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1247 | bad_no_bioset: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1248 | mempool_destroy(md->tio_pool); |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1249 | bad_tio_pool: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1250 | mempool_destroy(md->io_pool); |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1251 | bad_io_pool: |
Al Viro | 1312f40 | 2006-03-12 11:02:03 -0500 | [diff] [blame] | 1252 | blk_cleanup_queue(md->queue); |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1253 | bad_queue: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1254 | free_minor(minor); |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1255 | bad_minor: |
Jeff Mahoney | 10da4f7 | 2006-06-26 00:27:25 -0700 | [diff] [blame] | 1256 | module_put(THIS_MODULE); |
Milan Broz | 6ed7ade | 2008-02-08 02:10:19 +0000 | [diff] [blame] | 1257 | bad_module_get: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1258 | kfree(md); |
| 1259 | return NULL; |
| 1260 | } |
| 1261 | |
Jun'ichi Nomura | ae9da83 | 2007-10-19 22:38:43 +0100 | [diff] [blame] | 1262 | static void unlock_fs(struct mapped_device *md); |
| 1263 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1264 | static void free_dev(struct mapped_device *md) |
| 1265 | { |
Tejun Heo | f331c02 | 2008-09-03 09:01:48 +0200 | [diff] [blame] | 1266 | int minor = MINOR(disk_devt(md->disk)); |
Jun'ichi Nomura | 63d94e4 | 2006-02-24 13:04:25 -0800 | [diff] [blame] | 1267 | |
Mikulas Patocka | 32a926d | 2009-06-22 10:12:17 +0100 | [diff] [blame] | 1268 | unlock_fs(md); |
| 1269 | bdput(md->bdev); |
Milan Broz | 304f3f6 | 2008-02-08 02:11:17 +0000 | [diff] [blame] | 1270 | destroy_workqueue(md->wq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1271 | mempool_destroy(md->tio_pool); |
| 1272 | mempool_destroy(md->io_pool); |
Stefan Bader | 9faf400 | 2006-10-03 01:15:41 -0700 | [diff] [blame] | 1273 | bioset_free(md->bs); |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 1274 | blk_integrity_unregister(md->disk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1275 | del_gendisk(md->disk); |
Jun'ichi Nomura | 63d94e4 | 2006-02-24 13:04:25 -0800 | [diff] [blame] | 1276 | free_minor(minor); |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 1277 | |
| 1278 | spin_lock(&_minor_lock); |
| 1279 | md->disk->private_data = NULL; |
| 1280 | spin_unlock(&_minor_lock); |
| 1281 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1282 | put_disk(md->disk); |
Al Viro | 1312f40 | 2006-03-12 11:02:03 -0500 | [diff] [blame] | 1283 | blk_cleanup_queue(md->queue); |
Jeff Mahoney | 10da4f7 | 2006-06-26 00:27:25 -0700 | [diff] [blame] | 1284 | module_put(THIS_MODULE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1285 | kfree(md); |
| 1286 | } |
| 1287 | |
| 1288 | /* |
| 1289 | * Bind a table to the device. |
| 1290 | */ |
| 1291 | static void event_callback(void *context) |
| 1292 | { |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 1293 | unsigned long flags; |
| 1294 | LIST_HEAD(uevents); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1295 | struct mapped_device *md = (struct mapped_device *) context; |
| 1296 | |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 1297 | spin_lock_irqsave(&md->uevent_lock, flags); |
| 1298 | list_splice_init(&md->uevent_list, &uevents); |
| 1299 | spin_unlock_irqrestore(&md->uevent_lock, flags); |
| 1300 | |
Tejun Heo | ed9e198 | 2008-08-25 19:56:05 +0900 | [diff] [blame] | 1301 | dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 1302 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1303 | atomic_inc(&md->event_nr); |
| 1304 | wake_up(&md->eventq); |
| 1305 | } |
| 1306 | |
Alasdair G Kergon | 4e90188be | 2005-07-28 21:15:59 -0700 | [diff] [blame] | 1307 | static void __set_size(struct mapped_device *md, sector_t size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1308 | { |
Alasdair G Kergon | 4e90188be | 2005-07-28 21:15:59 -0700 | [diff] [blame] | 1309 | set_capacity(md->disk, size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1310 | |
Mikulas Patocka | db8fef4 | 2009-06-22 10:12:15 +0100 | [diff] [blame] | 1311 | mutex_lock(&md->bdev->bd_inode->i_mutex); |
| 1312 | i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
| 1313 | mutex_unlock(&md->bdev->bd_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1314 | } |
| 1315 | |
| 1316 | static int __bind(struct mapped_device *md, struct dm_table *t) |
| 1317 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1318 | struct request_queue *q = md->queue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1319 | sector_t size; |
| 1320 | |
| 1321 | size = dm_table_get_size(t); |
Darrick J. Wong | 3ac51e7 | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1322 | |
| 1323 | /* |
| 1324 | * Wipe any geometry if the size of the table changed. |
| 1325 | */ |
| 1326 | if (size != get_capacity(md->disk)) |
| 1327 | memset(&md->geometry, 0, sizeof(md->geometry)); |
| 1328 | |
Mikulas Patocka | 32a926d | 2009-06-22 10:12:17 +0100 | [diff] [blame] | 1329 | __set_size(md, size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1330 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 1331 | if (!size) { |
| 1332 | dm_table_destroy(t); |
| 1333 | return 0; |
| 1334 | } |
| 1335 | |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1336 | dm_table_event_callback(t, event_callback, md); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1337 | |
| 1338 | write_lock(&md->map_lock); |
| 1339 | md->map = t; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1340 | dm_table_set_restrictions(t, q); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1341 | write_unlock(&md->map_lock); |
| 1342 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1343 | return 0; |
| 1344 | } |
| 1345 | |
| 1346 | static void __unbind(struct mapped_device *md) |
| 1347 | { |
| 1348 | struct dm_table *map = md->map; |
| 1349 | |
| 1350 | if (!map) |
| 1351 | return; |
| 1352 | |
| 1353 | dm_table_event_callback(map, NULL, NULL); |
| 1354 | write_lock(&md->map_lock); |
| 1355 | md->map = NULL; |
| 1356 | write_unlock(&md->map_lock); |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 1357 | dm_table_destroy(map); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1358 | } |
| 1359 | |
| 1360 | /* |
| 1361 | * Constructor for a new device. |
| 1362 | */ |
Alasdair G Kergon | 2b06cff | 2006-06-26 00:27:32 -0700 | [diff] [blame] | 1363 | int dm_create(int minor, struct mapped_device **result) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1364 | { |
| 1365 | struct mapped_device *md; |
| 1366 | |
Alasdair G Kergon | 2b06cff | 2006-06-26 00:27:32 -0700 | [diff] [blame] | 1367 | md = alloc_dev(minor); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1368 | if (!md) |
| 1369 | return -ENXIO; |
| 1370 | |
Milan Broz | 784aae7 | 2009-01-06 03:05:12 +0000 | [diff] [blame] | 1371 | dm_sysfs_init(md); |
| 1372 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1373 | *result = md; |
| 1374 | return 0; |
| 1375 | } |
| 1376 | |
David Teigland | 637842c | 2006-01-06 00:20:00 -0800 | [diff] [blame] | 1377 | static struct mapped_device *dm_find_md(dev_t dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1378 | { |
| 1379 | struct mapped_device *md; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1380 | unsigned minor = MINOR(dev); |
| 1381 | |
| 1382 | if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) |
| 1383 | return NULL; |
| 1384 | |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1385 | spin_lock(&_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1386 | |
| 1387 | md = idr_find(&_minor_idr, minor); |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 1388 | if (md && (md == MINOR_ALLOCED || |
Tejun Heo | f331c02 | 2008-09-03 09:01:48 +0200 | [diff] [blame] | 1389 | (MINOR(disk_devt(dm_disk(md))) != minor) || |
Alasdair G Kergon | 17b2f66 | 2006-06-26 00:27:33 -0700 | [diff] [blame] | 1390 | test_bit(DMF_FREEING, &md->flags))) { |
David Teigland | 637842c | 2006-01-06 00:20:00 -0800 | [diff] [blame] | 1391 | md = NULL; |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 1392 | goto out; |
| 1393 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1394 | |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 1395 | out: |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1396 | spin_unlock(&_minor_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1397 | |
David Teigland | 637842c | 2006-01-06 00:20:00 -0800 | [diff] [blame] | 1398 | return md; |
| 1399 | } |
| 1400 | |
David Teigland | d229a95 | 2006-01-06 00:20:01 -0800 | [diff] [blame] | 1401 | struct mapped_device *dm_get_md(dev_t dev) |
| 1402 | { |
| 1403 | struct mapped_device *md = dm_find_md(dev); |
| 1404 | |
| 1405 | if (md) |
| 1406 | dm_get(md); |
| 1407 | |
| 1408 | return md; |
| 1409 | } |
| 1410 | |
Alasdair G Kergon | 9ade92a | 2006-03-27 01:17:53 -0800 | [diff] [blame] | 1411 | void *dm_get_mdptr(struct mapped_device *md) |
David Teigland | 637842c | 2006-01-06 00:20:00 -0800 | [diff] [blame] | 1412 | { |
Alasdair G Kergon | 9ade92a | 2006-03-27 01:17:53 -0800 | [diff] [blame] | 1413 | return md->interface_ptr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1414 | } |
| 1415 | |
| 1416 | void dm_set_mdptr(struct mapped_device *md, void *ptr) |
| 1417 | { |
| 1418 | md->interface_ptr = ptr; |
| 1419 | } |
| 1420 | |
| 1421 | void dm_get(struct mapped_device *md) |
| 1422 | { |
| 1423 | atomic_inc(&md->holders); |
| 1424 | } |
| 1425 | |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 1426 | const char *dm_device_name(struct mapped_device *md) |
| 1427 | { |
| 1428 | return md->name; |
| 1429 | } |
| 1430 | EXPORT_SYMBOL_GPL(dm_device_name); |
| 1431 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1432 | void dm_put(struct mapped_device *md) |
| 1433 | { |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1434 | struct dm_table *map; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1435 | |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 1436 | BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
| 1437 | |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1438 | if (atomic_dec_and_lock(&md->holders, &_minor_lock)) { |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1439 | map = dm_get_table(md); |
Tejun Heo | f331c02 | 2008-09-03 09:01:48 +0200 | [diff] [blame] | 1440 | idr_replace(&_minor_idr, MINOR_ALLOCED, |
| 1441 | MINOR(disk_devt(dm_disk(md)))); |
Jeff Mahoney | fba9f90 | 2006-06-26 00:27:23 -0700 | [diff] [blame] | 1442 | set_bit(DMF_FREEING, &md->flags); |
Jeff Mahoney | f32c10b | 2006-06-26 00:27:22 -0700 | [diff] [blame] | 1443 | spin_unlock(&_minor_lock); |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1444 | if (!dm_suspended(md)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1445 | dm_table_presuspend_targets(map); |
| 1446 | dm_table_postsuspend_targets(map); |
| 1447 | } |
Milan Broz | 784aae7 | 2009-01-06 03:05:12 +0000 | [diff] [blame] | 1448 | dm_sysfs_exit(md); |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1449 | dm_table_put(map); |
Mikulas Patocka | a1b51e9 | 2009-01-06 03:04:53 +0000 | [diff] [blame] | 1450 | __unbind(md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1451 | free_dev(md); |
| 1452 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1453 | } |
Edward Goggin | 79eb885 | 2007-05-09 02:32:56 -0700 | [diff] [blame] | 1454 | EXPORT_SYMBOL_GPL(dm_put); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1455 | |
Mikulas Patocka | 401600d | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1456 | static int dm_wait_for_completion(struct mapped_device *md, int interruptible) |
Milan Broz | 46125c1 | 2008-02-08 02:10:30 +0000 | [diff] [blame] | 1457 | { |
| 1458 | int r = 0; |
Mikulas Patocka | b44ebeb | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 1459 | DECLARE_WAITQUEUE(wait, current); |
| 1460 | |
| 1461 | dm_unplug_all(md->queue); |
| 1462 | |
| 1463 | add_wait_queue(&md->wait, &wait); |
Milan Broz | 46125c1 | 2008-02-08 02:10:30 +0000 | [diff] [blame] | 1464 | |
| 1465 | while (1) { |
Mikulas Patocka | 401600d | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1466 | set_current_state(interruptible); |
Milan Broz | 46125c1 | 2008-02-08 02:10:30 +0000 | [diff] [blame] | 1467 | |
| 1468 | smp_mb(); |
| 1469 | if (!atomic_read(&md->pending)) |
| 1470 | break; |
| 1471 | |
Mikulas Patocka | 401600d | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1472 | if (interruptible == TASK_INTERRUPTIBLE && |
| 1473 | signal_pending(current)) { |
Milan Broz | 46125c1 | 2008-02-08 02:10:30 +0000 | [diff] [blame] | 1474 | r = -EINTR; |
| 1475 | break; |
| 1476 | } |
| 1477 | |
| 1478 | io_schedule(); |
| 1479 | } |
| 1480 | set_current_state(TASK_RUNNING); |
| 1481 | |
Mikulas Patocka | b44ebeb | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 1482 | remove_wait_queue(&md->wait, &wait); |
| 1483 | |
Milan Broz | 46125c1 | 2008-02-08 02:10:30 +0000 | [diff] [blame] | 1484 | return r; |
| 1485 | } |
| 1486 | |
Mikulas Patocka | 531fe96 | 2009-06-22 10:12:17 +0100 | [diff] [blame] | 1487 | static void dm_flush(struct mapped_device *md) |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 1488 | { |
| 1489 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); |
Mikulas Patocka | 52b1fd5 | 2009-06-22 10:12:21 +0100 | [diff] [blame] | 1490 | |
| 1491 | bio_init(&md->barrier_bio); |
| 1492 | md->barrier_bio.bi_bdev = md->bdev; |
| 1493 | md->barrier_bio.bi_rw = WRITE_BARRIER; |
| 1494 | __split_and_process_bio(md, &md->barrier_bio); |
| 1495 | |
| 1496 | dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 1497 | } |
| 1498 | |
| 1499 | static void process_barrier(struct mapped_device *md, struct bio *bio) |
| 1500 | { |
Mikulas Patocka | 5aa2781 | 2009-06-22 10:12:18 +0100 | [diff] [blame] | 1501 | md->barrier_error = 0; |
| 1502 | |
Mikulas Patocka | 531fe96 | 2009-06-22 10:12:17 +0100 | [diff] [blame] | 1503 | dm_flush(md); |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 1504 | |
Mikulas Patocka | 5aa2781 | 2009-06-22 10:12:18 +0100 | [diff] [blame] | 1505 | if (!bio_empty_barrier(bio)) { |
| 1506 | __split_and_process_bio(md, bio); |
| 1507 | dm_flush(md); |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 1508 | } |
| 1509 | |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 1510 | if (md->barrier_error != DM_ENDIO_REQUEUE) |
Mikulas Patocka | 531fe96 | 2009-06-22 10:12:17 +0100 | [diff] [blame] | 1511 | bio_endio(bio, md->barrier_error); |
Mikulas Patocka | 2761e95 | 2009-06-22 10:12:18 +0100 | [diff] [blame] | 1512 | else { |
| 1513 | spin_lock_irq(&md->deferred_lock); |
| 1514 | bio_list_add_head(&md->deferred, bio); |
| 1515 | spin_unlock_irq(&md->deferred_lock); |
| 1516 | } |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 1517 | } |
| 1518 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1519 | /* |
| 1520 | * Process the deferred bios |
| 1521 | */ |
Mikulas Patocka | ef20858 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1522 | static void dm_wq_work(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1523 | { |
Mikulas Patocka | ef20858 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1524 | struct mapped_device *md = container_of(work, struct mapped_device, |
| 1525 | work); |
Milan Broz | 6d6f10d | 2008-02-08 02:10:22 +0000 | [diff] [blame] | 1526 | struct bio *c; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1527 | |
Mikulas Patocka | ef20858 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1528 | down_write(&md->io_lock); |
| 1529 | |
Mikulas Patocka | 3b00b20 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1530 | while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
Alasdair G Kergon | df12ee9 | 2009-04-09 00:27:13 +0100 | [diff] [blame] | 1531 | spin_lock_irq(&md->deferred_lock); |
| 1532 | c = bio_list_pop(&md->deferred); |
| 1533 | spin_unlock_irq(&md->deferred_lock); |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 1534 | |
Alasdair G Kergon | df12ee9 | 2009-04-09 00:27:13 +0100 | [diff] [blame] | 1535 | if (!c) { |
Alasdair G Kergon | 1eb787e | 2009-04-09 00:27:14 +0100 | [diff] [blame] | 1536 | clear_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags); |
Alasdair G Kergon | df12ee9 | 2009-04-09 00:27:13 +0100 | [diff] [blame] | 1537 | break; |
| 1538 | } |
| 1539 | |
Mikulas Patocka | 3b00b20 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1540 | up_write(&md->io_lock); |
| 1541 | |
Mikulas Patocka | af7e466 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 1542 | if (bio_barrier(c)) |
| 1543 | process_barrier(md, c); |
| 1544 | else |
| 1545 | __split_and_process_bio(md, c); |
Mikulas Patocka | 3b00b20 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1546 | |
| 1547 | down_write(&md->io_lock); |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 1548 | } |
Milan Broz | 73d410c | 2008-02-08 02:10:25 +0000 | [diff] [blame] | 1549 | |
Mikulas Patocka | ef20858 | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1550 | up_write(&md->io_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1551 | } |
| 1552 | |
Mikulas Patocka | 9a1fb46 | 2009-04-02 19:55:36 +0100 | [diff] [blame] | 1553 | static void dm_queue_flush(struct mapped_device *md) |
Milan Broz | 304f3f6 | 2008-02-08 02:11:17 +0000 | [diff] [blame] | 1554 | { |
Mikulas Patocka | 3b00b20 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1555 | clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
| 1556 | smp_mb__after_clear_bit(); |
Mikulas Patocka | 53d5914 | 2009-04-02 19:55:37 +0100 | [diff] [blame] | 1557 | queue_work(md->wq, &md->work); |
Milan Broz | 304f3f6 | 2008-02-08 02:11:17 +0000 | [diff] [blame] | 1558 | } |
| 1559 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1560 | /* |
| 1561 | * Swap in a new table (destroying old one). |
| 1562 | */ |
| 1563 | int dm_swap_table(struct mapped_device *md, struct dm_table *table) |
| 1564 | { |
Alasdair G Kergon | 93c534a | 2005-07-12 15:53:05 -0700 | [diff] [blame] | 1565 | int r = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1566 | |
Daniel Walker | e61290a | 2008-02-08 02:10:08 +0000 | [diff] [blame] | 1567 | mutex_lock(&md->suspend_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1568 | |
| 1569 | /* device must be suspended */ |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1570 | if (!dm_suspended(md)) |
Alasdair G Kergon | 93c534a | 2005-07-12 15:53:05 -0700 | [diff] [blame] | 1571 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1572 | |
| 1573 | __unbind(md); |
| 1574 | r = __bind(md, table); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1575 | |
Alasdair G Kergon | 93c534a | 2005-07-12 15:53:05 -0700 | [diff] [blame] | 1576 | out: |
Daniel Walker | e61290a | 2008-02-08 02:10:08 +0000 | [diff] [blame] | 1577 | mutex_unlock(&md->suspend_lock); |
Alasdair G Kergon | 93c534a | 2005-07-12 15:53:05 -0700 | [diff] [blame] | 1578 | return r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1579 | } |
| 1580 | |
| 1581 | /* |
| 1582 | * Functions to lock and unlock any filesystem running on the |
| 1583 | * device. |
| 1584 | */ |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1585 | static int lock_fs(struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1586 | { |
Alasdair G Kergon | e39e2e9 | 2006-01-06 00:20:05 -0800 | [diff] [blame] | 1587 | int r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1588 | |
| 1589 | WARN_ON(md->frozen_sb); |
Alasdair G Kergon | dfbe03f | 2005-05-05 16:16:04 -0700 | [diff] [blame] | 1590 | |
Mikulas Patocka | db8fef4 | 2009-06-22 10:12:15 +0100 | [diff] [blame] | 1591 | md->frozen_sb = freeze_bdev(md->bdev); |
Alasdair G Kergon | dfbe03f | 2005-05-05 16:16:04 -0700 | [diff] [blame] | 1592 | if (IS_ERR(md->frozen_sb)) { |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1593 | r = PTR_ERR(md->frozen_sb); |
Alasdair G Kergon | e39e2e9 | 2006-01-06 00:20:05 -0800 | [diff] [blame] | 1594 | md->frozen_sb = NULL; |
| 1595 | return r; |
Alasdair G Kergon | dfbe03f | 2005-05-05 16:16:04 -0700 | [diff] [blame] | 1596 | } |
| 1597 | |
Alasdair G Kergon | aa8d7c2 | 2006-01-06 00:20:06 -0800 | [diff] [blame] | 1598 | set_bit(DMF_FROZEN, &md->flags); |
| 1599 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1600 | return 0; |
| 1601 | } |
| 1602 | |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1603 | static void unlock_fs(struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1604 | { |
Alasdair G Kergon | aa8d7c2 | 2006-01-06 00:20:06 -0800 | [diff] [blame] | 1605 | if (!test_bit(DMF_FROZEN, &md->flags)) |
| 1606 | return; |
| 1607 | |
Mikulas Patocka | db8fef4 | 2009-06-22 10:12:15 +0100 | [diff] [blame] | 1608 | thaw_bdev(md->bdev, md->frozen_sb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1609 | md->frozen_sb = NULL; |
Alasdair G Kergon | aa8d7c2 | 2006-01-06 00:20:06 -0800 | [diff] [blame] | 1610 | clear_bit(DMF_FROZEN, &md->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1611 | } |
| 1612 | |
| 1613 | /* |
| 1614 | * We need to be able to change a mapping table under a mounted |
| 1615 | * filesystem. For example we might want to move some data in |
| 1616 | * the background. Before the table can be swapped with |
| 1617 | * dm_bind_table, dm_suspend must be called to flush any in |
| 1618 | * flight bios and ensure that any further io gets deferred. |
| 1619 | */ |
Kiyoshi Ueda | a3d77d3 | 2006-12-08 02:41:04 -0800 | [diff] [blame] | 1620 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1621 | { |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1622 | struct dm_table *map = NULL; |
Milan Broz | 46125c1 | 2008-02-08 02:10:30 +0000 | [diff] [blame] | 1623 | int r = 0; |
Kiyoshi Ueda | a3d77d3 | 2006-12-08 02:41:04 -0800 | [diff] [blame] | 1624 | int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0; |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 1625 | int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1626 | |
Daniel Walker | e61290a | 2008-02-08 02:10:08 +0000 | [diff] [blame] | 1627 | mutex_lock(&md->suspend_lock); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1628 | |
Milan Broz | 73d410c | 2008-02-08 02:10:25 +0000 | [diff] [blame] | 1629 | if (dm_suspended(md)) { |
| 1630 | r = -EINVAL; |
Alasdair G Kergon | d287483 | 2006-11-08 17:44:43 -0800 | [diff] [blame] | 1631 | goto out_unlock; |
Milan Broz | 73d410c | 2008-02-08 02:10:25 +0000 | [diff] [blame] | 1632 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1633 | |
| 1634 | map = dm_get_table(md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1635 | |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 1636 | /* |
| 1637 | * DMF_NOFLUSH_SUSPENDING must be set before presuspend. |
| 1638 | * This flag is cleared before dm_suspend returns. |
| 1639 | */ |
| 1640 | if (noflush) |
| 1641 | set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
| 1642 | |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1643 | /* This does not get reverted if there's an error later. */ |
| 1644 | dm_table_presuspend_targets(map); |
| 1645 | |
Mikulas Patocka | 32a926d | 2009-06-22 10:12:17 +0100 | [diff] [blame] | 1646 | /* |
| 1647 | * Flush I/O to the device. noflush supersedes do_lockfs, |
| 1648 | * because lock_fs() needs to flush I/Os. |
| 1649 | */ |
| 1650 | if (!noflush && do_lockfs) { |
| 1651 | r = lock_fs(md); |
| 1652 | if (r) |
Kiyoshi Ueda | f431d96 | 2008-10-21 17:45:07 +0100 | [diff] [blame] | 1653 | goto out; |
Alasdair G Kergon | aa8d7c2 | 2006-01-06 00:20:06 -0800 | [diff] [blame] | 1654 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1655 | |
| 1656 | /* |
Mikulas Patocka | 3b00b20 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1657 | * Here we must make sure that no processes are submitting requests |
| 1658 | * to target drivers i.e. no one may be executing |
| 1659 | * __split_and_process_bio. This is called from dm_request and |
| 1660 | * dm_wq_work. |
| 1661 | * |
| 1662 | * To get all processes out of __split_and_process_bio in dm_request, |
| 1663 | * we take the write lock. To prevent any process from reentering |
| 1664 | * __split_and_process_bio from dm_request, we set |
| 1665 | * DMF_QUEUE_IO_TO_THREAD. |
| 1666 | * |
| 1667 | * To quiesce the thread (dm_wq_work), we set DMF_BLOCK_IO_FOR_SUSPEND |
| 1668 | * and call flush_workqueue(md->wq). flush_workqueue will wait until |
| 1669 | * dm_wq_work exits and DMF_BLOCK_IO_FOR_SUSPEND will prevent any |
| 1670 | * further calls to __split_and_process_bio from dm_wq_work. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1671 | */ |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1672 | down_write(&md->io_lock); |
Alasdair G Kergon | 1eb787e | 2009-04-09 00:27:14 +0100 | [diff] [blame] | 1673 | set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
| 1674 | set_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1675 | up_write(&md->io_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1676 | |
Mikulas Patocka | 3b00b20 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1677 | flush_workqueue(md->wq); |
| 1678 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1679 | /* |
Mikulas Patocka | 3b00b20 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1680 | * At this point no more requests are entering target request routines. |
| 1681 | * We call dm_wait_for_completion to wait for all existing requests |
| 1682 | * to finish. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1683 | */ |
Mikulas Patocka | 401600d | 2009-04-02 19:55:38 +0100 | [diff] [blame] | 1684 | r = dm_wait_for_completion(md, TASK_INTERRUPTIBLE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1685 | |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1686 | down_write(&md->io_lock); |
Milan Broz | 6d6f10d | 2008-02-08 02:10:22 +0000 | [diff] [blame] | 1687 | if (noflush) |
Mikulas Patocka | 022c261 | 2009-04-02 19:55:39 +0100 | [diff] [blame] | 1688 | clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
Milan Broz | 94d6351 | 2008-02-08 02:10:27 +0000 | [diff] [blame] | 1689 | up_write(&md->io_lock); |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 1690 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1691 | /* were we interrupted ? */ |
Milan Broz | 46125c1 | 2008-02-08 02:10:30 +0000 | [diff] [blame] | 1692 | if (r < 0) { |
Mikulas Patocka | 9a1fb46 | 2009-04-02 19:55:36 +0100 | [diff] [blame] | 1693 | dm_queue_flush(md); |
Milan Broz | 73d410c | 2008-02-08 02:10:25 +0000 | [diff] [blame] | 1694 | |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1695 | unlock_fs(md); |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 1696 | goto out; /* pushback list is already flushed, so skip flush */ |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1697 | } |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1698 | |
Mikulas Patocka | 3b00b20 | 2009-04-09 00:27:15 +0100 | [diff] [blame] | 1699 | /* |
| 1700 | * If dm_wait_for_completion returned 0, the device is completely |
| 1701 | * quiescent now. There is no request-processing activity. All new |
| 1702 | * requests are being added to md->deferred list. |
| 1703 | */ |
| 1704 | |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1705 | dm_table_postsuspend_targets(map); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1706 | |
| 1707 | set_bit(DMF_SUSPENDED, &md->flags); |
| 1708 | |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1709 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1710 | dm_table_put(map); |
Alasdair G Kergon | d287483 | 2006-11-08 17:44:43 -0800 | [diff] [blame] | 1711 | |
| 1712 | out_unlock: |
Daniel Walker | e61290a | 2008-02-08 02:10:08 +0000 | [diff] [blame] | 1713 | mutex_unlock(&md->suspend_lock); |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1714 | return r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1715 | } |
| 1716 | |
| 1717 | int dm_resume(struct mapped_device *md) |
| 1718 | { |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1719 | int r = -EINVAL; |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1720 | struct dm_table *map = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1721 | |
Daniel Walker | e61290a | 2008-02-08 02:10:08 +0000 | [diff] [blame] | 1722 | mutex_lock(&md->suspend_lock); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1723 | if (!dm_suspended(md)) |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1724 | goto out; |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1725 | |
| 1726 | map = dm_get_table(md); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1727 | if (!map || !dm_table_get_size(map)) |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1728 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1729 | |
Milan Broz | 8757b77 | 2006-10-03 01:15:36 -0700 | [diff] [blame] | 1730 | r = dm_table_resume_targets(map); |
| 1731 | if (r) |
| 1732 | goto out; |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1733 | |
Mikulas Patocka | 9a1fb46 | 2009-04-02 19:55:36 +0100 | [diff] [blame] | 1734 | dm_queue_flush(md); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1735 | |
| 1736 | unlock_fs(md); |
| 1737 | |
| 1738 | clear_bit(DMF_SUSPENDED, &md->flags); |
| 1739 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1740 | dm_table_unplug_all(map); |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1741 | r = 0; |
| 1742 | out: |
| 1743 | dm_table_put(map); |
Daniel Walker | e61290a | 2008-02-08 02:10:08 +0000 | [diff] [blame] | 1744 | mutex_unlock(&md->suspend_lock); |
Alasdair G Kergon | 2ca3310 | 2005-07-28 21:16:00 -0700 | [diff] [blame] | 1745 | |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1746 | return r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1747 | } |
| 1748 | |
| 1749 | /*----------------------------------------------------------------- |
| 1750 | * Event notification. |
| 1751 | *---------------------------------------------------------------*/ |
Milan Broz | 60935eb | 2009-06-22 10:12:30 +0100 | [diff] [blame^] | 1752 | void dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
| 1753 | unsigned cookie) |
Alasdair G Kergon | 69267a3 | 2007-12-13 14:15:57 +0000 | [diff] [blame] | 1754 | { |
Milan Broz | 60935eb | 2009-06-22 10:12:30 +0100 | [diff] [blame^] | 1755 | char udev_cookie[DM_COOKIE_LENGTH]; |
| 1756 | char *envp[] = { udev_cookie, NULL }; |
| 1757 | |
| 1758 | if (!cookie) |
| 1759 | kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
| 1760 | else { |
| 1761 | snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", |
| 1762 | DM_COOKIE_ENV_VAR_NAME, cookie); |
| 1763 | kobject_uevent_env(&disk_to_dev(md->disk)->kobj, action, envp); |
| 1764 | } |
Alasdair G Kergon | 69267a3 | 2007-12-13 14:15:57 +0000 | [diff] [blame] | 1765 | } |
| 1766 | |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 1767 | uint32_t dm_next_uevent_seq(struct mapped_device *md) |
| 1768 | { |
| 1769 | return atomic_add_return(1, &md->uevent_seq); |
| 1770 | } |
| 1771 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1772 | uint32_t dm_get_event_nr(struct mapped_device *md) |
| 1773 | { |
| 1774 | return atomic_read(&md->event_nr); |
| 1775 | } |
| 1776 | |
| 1777 | int dm_wait_event(struct mapped_device *md, int event_nr) |
| 1778 | { |
| 1779 | return wait_event_interruptible(md->eventq, |
| 1780 | (event_nr != atomic_read(&md->event_nr))); |
| 1781 | } |
| 1782 | |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 1783 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
| 1784 | { |
| 1785 | unsigned long flags; |
| 1786 | |
| 1787 | spin_lock_irqsave(&md->uevent_lock, flags); |
| 1788 | list_add(elist, &md->uevent_list); |
| 1789 | spin_unlock_irqrestore(&md->uevent_lock, flags); |
| 1790 | } |
| 1791 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1792 | /* |
| 1793 | * The gendisk is only valid as long as you have a reference |
| 1794 | * count on 'md'. |
| 1795 | */ |
| 1796 | struct gendisk *dm_disk(struct mapped_device *md) |
| 1797 | { |
| 1798 | return md->disk; |
| 1799 | } |
| 1800 | |
Milan Broz | 784aae7 | 2009-01-06 03:05:12 +0000 | [diff] [blame] | 1801 | struct kobject *dm_kobject(struct mapped_device *md) |
| 1802 | { |
| 1803 | return &md->kobj; |
| 1804 | } |
| 1805 | |
| 1806 | /* |
| 1807 | * struct mapped_device should not be exported outside of dm.c |
| 1808 | * so use this check to verify that kobj is part of md structure |
| 1809 | */ |
| 1810 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj) |
| 1811 | { |
| 1812 | struct mapped_device *md; |
| 1813 | |
| 1814 | md = container_of(kobj, struct mapped_device, kobj); |
| 1815 | if (&md->kobj != kobj) |
| 1816 | return NULL; |
| 1817 | |
Milan Broz | 4d89b7b | 2009-06-22 10:12:11 +0100 | [diff] [blame] | 1818 | if (test_bit(DMF_FREEING, &md->flags) || |
| 1819 | test_bit(DMF_DELETING, &md->flags)) |
| 1820 | return NULL; |
| 1821 | |
Milan Broz | 784aae7 | 2009-01-06 03:05:12 +0000 | [diff] [blame] | 1822 | dm_get(md); |
| 1823 | return md; |
| 1824 | } |
| 1825 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1826 | int dm_suspended(struct mapped_device *md) |
| 1827 | { |
| 1828 | return test_bit(DMF_SUSPENDED, &md->flags); |
| 1829 | } |
| 1830 | |
Kiyoshi Ueda | 2e93ccc | 2006-12-08 02:41:09 -0800 | [diff] [blame] | 1831 | int dm_noflush_suspending(struct dm_target *ti) |
| 1832 | { |
| 1833 | struct mapped_device *md = dm_table_get_md(ti->table); |
| 1834 | int r = __noflush_suspending(md); |
| 1835 | |
| 1836 | dm_put(md); |
| 1837 | |
| 1838 | return r; |
| 1839 | } |
| 1840 | EXPORT_SYMBOL_GPL(dm_noflush_suspending); |
| 1841 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1842 | static struct block_device_operations dm_blk_dops = { |
| 1843 | .open = dm_blk_open, |
| 1844 | .release = dm_blk_close, |
Milan Broz | aa129a2 | 2006-10-03 01:15:15 -0700 | [diff] [blame] | 1845 | .ioctl = dm_blk_ioctl, |
Darrick J. Wong | 3ac51e7 | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1846 | .getgeo = dm_blk_getgeo, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1847 | .owner = THIS_MODULE |
| 1848 | }; |
| 1849 | |
| 1850 | EXPORT_SYMBOL(dm_get_mapinfo); |
| 1851 | |
| 1852 | /* |
| 1853 | * module hooks |
| 1854 | */ |
| 1855 | module_init(dm_init); |
| 1856 | module_exit(dm_exit); |
| 1857 | |
| 1858 | module_param(major, uint, 0); |
| 1859 | MODULE_PARM_DESC(major, "The major number of the device mapper"); |
| 1860 | MODULE_DESCRIPTION(DM_NAME " driver"); |
| 1861 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); |
| 1862 | MODULE_LICENSE("GPL"); |