Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2002 Sistina Software (UK) Limited. |
Milan Broz | 373a392 | 2007-05-09 02:33:02 -0700 | [diff] [blame] | 3 | * Copyright (C) 2006 Red Hat GmbH |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * |
| 5 | * This file is released under the GPL. |
| 6 | * |
| 7 | * Kcopyd provides a simple interface for copying an area of one |
| 8 | * block-device to one or more other block-devices, with an asynchronous |
| 9 | * completion notification. |
| 10 | */ |
| 11 | |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 12 | #include <linux/types.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <asm/atomic.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/blkdev.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/fs.h> |
| 16 | #include <linux/init.h> |
| 17 | #include <linux/list.h> |
| 18 | #include <linux/mempool.h> |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/pagemap.h> |
| 21 | #include <linux/slab.h> |
| 22 | #include <linux/vmalloc.h> |
| 23 | #include <linux/workqueue.h> |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 24 | #include <linux/mutex.h> |
Mikulas Patocka | 586e80e | 2008-10-21 17:44:59 +0100 | [diff] [blame] | 25 | #include <linux/device-mapper.h> |
Alasdair G Kergon | a765e20 | 2008-04-24 22:02:01 +0100 | [diff] [blame] | 26 | #include <linux/dm-kcopyd.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | |
Heinz Mauelshagen | 22a1ceb | 2008-04-24 21:43:17 +0100 | [diff] [blame] | 28 | #include "dm.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 30 | #define SUB_JOB_SIZE 128 |
| 31 | #define SPLIT_COUNT 8 |
| 32 | #define MIN_JOBS 8 |
| 33 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | /*----------------------------------------------------------------- |
| 35 | * Each kcopyd client has its own little pool of preallocated |
| 36 | * pages for kcopyd io. |
| 37 | *---------------------------------------------------------------*/ |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 38 | struct dm_kcopyd_client { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | struct page_list *pages; |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 40 | unsigned nr_reserved_pages; |
| 41 | unsigned nr_free_pages; |
Alasdair G Kergon | 138728dc | 2006-03-27 01:17:50 -0800 | [diff] [blame] | 42 | |
Milan Broz | 373a392 | 2007-05-09 02:33:02 -0700 | [diff] [blame] | 43 | struct dm_io_client *io_client; |
| 44 | |
Alasdair G Kergon | 138728dc | 2006-03-27 01:17:50 -0800 | [diff] [blame] | 45 | wait_queue_head_t destroyq; |
| 46 | atomic_t nr_jobs; |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 47 | |
Mikulas Patocka | 08d8757 | 2008-04-24 21:43:46 +0100 | [diff] [blame] | 48 | mempool_t *job_pool; |
| 49 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 50 | struct workqueue_struct *kcopyd_wq; |
| 51 | struct work_struct kcopyd_work; |
| 52 | |
| 53 | /* |
| 54 | * We maintain three lists of jobs: |
| 55 | * |
| 56 | * i) jobs waiting for pages |
| 57 | * ii) jobs that have pages, and are waiting for the io to be issued. |
| 58 | * iii) jobs that have completed. |
| 59 | * |
| 60 | * All three of these are protected by job_lock. |
| 61 | */ |
| 62 | spinlock_t job_lock; |
| 63 | struct list_head complete_jobs; |
| 64 | struct list_head io_jobs; |
| 65 | struct list_head pages_jobs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | }; |
| 67 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 68 | static void wake(struct dm_kcopyd_client *kc) |
| 69 | { |
| 70 | queue_work(kc->kcopyd_wq, &kc->kcopyd_work); |
| 71 | } |
| 72 | |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 73 | /* |
| 74 | * Obtain one page for the use of kcopyd. |
| 75 | */ |
Mikulas Patocka | f99b55e | 2011-05-29 13:03:04 +0100 | [diff] [blame] | 76 | static struct page_list *alloc_pl(gfp_t gfp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | { |
| 78 | struct page_list *pl; |
| 79 | |
Mikulas Patocka | f99b55e | 2011-05-29 13:03:04 +0100 | [diff] [blame] | 80 | pl = kmalloc(sizeof(*pl), gfp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | if (!pl) |
| 82 | return NULL; |
| 83 | |
Mikulas Patocka | f99b55e | 2011-05-29 13:03:04 +0100 | [diff] [blame] | 84 | pl->page = alloc_page(gfp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | if (!pl->page) { |
| 86 | kfree(pl); |
| 87 | return NULL; |
| 88 | } |
| 89 | |
| 90 | return pl; |
| 91 | } |
| 92 | |
| 93 | static void free_pl(struct page_list *pl) |
| 94 | { |
| 95 | __free_page(pl->page); |
| 96 | kfree(pl); |
| 97 | } |
| 98 | |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 99 | /* |
| 100 | * Add the provided pages to a client's free page list, releasing |
| 101 | * back to the system any beyond the reserved_pages limit. |
| 102 | */ |
| 103 | static void kcopyd_put_pages(struct dm_kcopyd_client *kc, struct page_list *pl) |
| 104 | { |
| 105 | struct page_list *next; |
| 106 | |
| 107 | do { |
| 108 | next = pl->next; |
| 109 | |
| 110 | if (kc->nr_free_pages >= kc->nr_reserved_pages) |
| 111 | free_pl(pl); |
| 112 | else { |
| 113 | pl->next = kc->pages; |
| 114 | kc->pages = pl; |
| 115 | kc->nr_free_pages++; |
| 116 | } |
| 117 | |
| 118 | pl = next; |
| 119 | } while (pl); |
| 120 | } |
| 121 | |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 122 | static int kcopyd_get_pages(struct dm_kcopyd_client *kc, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | unsigned int nr, struct page_list **pages) |
| 124 | { |
| 125 | struct page_list *pl; |
| 126 | |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 127 | *pages = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 129 | do { |
| 130 | pl = alloc_pl(__GFP_NOWARN | __GFP_NORETRY); |
| 131 | if (unlikely(!pl)) { |
| 132 | /* Use reserved pages */ |
| 133 | pl = kc->pages; |
| 134 | if (unlikely(!pl)) |
| 135 | goto out_of_memory; |
| 136 | kc->pages = pl->next; |
| 137 | kc->nr_free_pages--; |
| 138 | } |
| 139 | pl->next = *pages; |
| 140 | *pages = pl; |
| 141 | } while (--nr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 145 | out_of_memory: |
| 146 | if (*pages) |
| 147 | kcopyd_put_pages(kc, *pages); |
| 148 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | } |
| 150 | |
| 151 | /* |
| 152 | * These three functions resize the page pool. |
| 153 | */ |
| 154 | static void drop_pages(struct page_list *pl) |
| 155 | { |
| 156 | struct page_list *next; |
| 157 | |
| 158 | while (pl) { |
| 159 | next = pl->next; |
| 160 | free_pl(pl); |
| 161 | pl = next; |
| 162 | } |
| 163 | } |
| 164 | |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 165 | /* |
| 166 | * Allocate and reserve nr_pages for the use of a specific client. |
| 167 | */ |
| 168 | static int client_reserve_pages(struct dm_kcopyd_client *kc, unsigned nr_pages) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | { |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 170 | unsigned i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | struct page_list *pl = NULL, *next; |
| 172 | |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 173 | for (i = 0; i < nr_pages; i++) { |
Mikulas Patocka | f99b55e | 2011-05-29 13:03:04 +0100 | [diff] [blame] | 174 | next = alloc_pl(GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 175 | if (!next) { |
| 176 | if (pl) |
| 177 | drop_pages(pl); |
| 178 | return -ENOMEM; |
| 179 | } |
| 180 | next->next = pl; |
| 181 | pl = next; |
| 182 | } |
| 183 | |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 184 | kc->nr_reserved_pages += nr_pages; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | kcopyd_put_pages(kc, pl); |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 186 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | return 0; |
| 188 | } |
| 189 | |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 190 | static void client_free_pages(struct dm_kcopyd_client *kc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | { |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 192 | BUG_ON(kc->nr_free_pages != kc->nr_reserved_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | drop_pages(kc->pages); |
| 194 | kc->pages = NULL; |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 195 | kc->nr_free_pages = kc->nr_reserved_pages = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | } |
| 197 | |
| 198 | /*----------------------------------------------------------------- |
| 199 | * kcopyd_jobs need to be allocated by the *clients* of kcopyd, |
| 200 | * for this reason we use a mempool to prevent the client from |
| 201 | * ever having to do io (which could cause a deadlock). |
| 202 | *---------------------------------------------------------------*/ |
| 203 | struct kcopyd_job { |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 204 | struct dm_kcopyd_client *kc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | struct list_head list; |
| 206 | unsigned long flags; |
| 207 | |
| 208 | /* |
| 209 | * Error state of the job. |
| 210 | */ |
| 211 | int read_err; |
Alasdair G Kergon | 4cdc1d1 | 2008-03-28 14:16:10 -0700 | [diff] [blame] | 212 | unsigned long write_err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | |
| 214 | /* |
| 215 | * Either READ or WRITE |
| 216 | */ |
| 217 | int rw; |
Heinz Mauelshagen | 22a1ceb | 2008-04-24 21:43:17 +0100 | [diff] [blame] | 218 | struct dm_io_region source; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | |
| 220 | /* |
| 221 | * The destinations for the transfer. |
| 222 | */ |
| 223 | unsigned int num_dests; |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 224 | struct dm_io_region dests[DM_KCOPYD_MAX_REGIONS]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | |
| 226 | sector_t offset; |
| 227 | unsigned int nr_pages; |
| 228 | struct page_list *pages; |
| 229 | |
| 230 | /* |
| 231 | * Set this to ensure you are notified when the job has |
| 232 | * completed. 'context' is for callback to use. |
| 233 | */ |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 234 | dm_kcopyd_notify_fn fn; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | void *context; |
| 236 | |
| 237 | /* |
| 238 | * These fields are only used if the job has been split |
| 239 | * into more manageable parts. |
| 240 | */ |
Matthias Kaehlcke | def5b5b | 2007-10-19 22:38:52 +0100 | [diff] [blame] | 241 | struct mutex lock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | atomic_t sub_jobs; |
| 243 | sector_t progress; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 245 | struct kcopyd_job *master_job; |
| 246 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 248 | static struct kmem_cache *_job_cache; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 250 | int __init dm_kcopyd_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | { |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 252 | _job_cache = kmem_cache_create("kcopyd_job", |
| 253 | sizeof(struct kcopyd_job) * (SPLIT_COUNT + 1), |
| 254 | __alignof__(struct kcopyd_job), 0, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | if (!_job_cache) |
| 256 | return -ENOMEM; |
| 257 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | return 0; |
| 259 | } |
| 260 | |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 261 | void dm_kcopyd_exit(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 262 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | kmem_cache_destroy(_job_cache); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | _job_cache = NULL; |
| 265 | } |
| 266 | |
| 267 | /* |
| 268 | * Functions to push and pop a job onto the head of a given job |
| 269 | * list. |
| 270 | */ |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 271 | static struct kcopyd_job *pop(struct list_head *jobs, |
| 272 | struct dm_kcopyd_client *kc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | { |
| 274 | struct kcopyd_job *job = NULL; |
| 275 | unsigned long flags; |
| 276 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 277 | spin_lock_irqsave(&kc->job_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | |
| 279 | if (!list_empty(jobs)) { |
| 280 | job = list_entry(jobs->next, struct kcopyd_job, list); |
| 281 | list_del(&job->list); |
| 282 | } |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 283 | spin_unlock_irqrestore(&kc->job_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | |
| 285 | return job; |
| 286 | } |
| 287 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 288 | static void push(struct list_head *jobs, struct kcopyd_job *job) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | { |
| 290 | unsigned long flags; |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 291 | struct dm_kcopyd_client *kc = job->kc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 293 | spin_lock_irqsave(&kc->job_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | list_add_tail(&job->list, jobs); |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 295 | spin_unlock_irqrestore(&kc->job_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | } |
| 297 | |
Kazuo Ito | b673c3a | 2008-10-21 17:44:50 +0100 | [diff] [blame] | 298 | |
| 299 | static void push_head(struct list_head *jobs, struct kcopyd_job *job) |
| 300 | { |
| 301 | unsigned long flags; |
| 302 | struct dm_kcopyd_client *kc = job->kc; |
| 303 | |
| 304 | spin_lock_irqsave(&kc->job_lock, flags); |
| 305 | list_add(&job->list, jobs); |
| 306 | spin_unlock_irqrestore(&kc->job_lock, flags); |
| 307 | } |
| 308 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | /* |
| 310 | * These three functions process 1 item from the corresponding |
| 311 | * job list. |
| 312 | * |
| 313 | * They return: |
| 314 | * < 0: error |
| 315 | * 0: success |
| 316 | * > 0: can't process yet. |
| 317 | */ |
| 318 | static int run_complete_job(struct kcopyd_job *job) |
| 319 | { |
| 320 | void *context = job->context; |
| 321 | int read_err = job->read_err; |
Alasdair G Kergon | 4cdc1d1 | 2008-03-28 14:16:10 -0700 | [diff] [blame] | 322 | unsigned long write_err = job->write_err; |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 323 | dm_kcopyd_notify_fn fn = job->fn; |
| 324 | struct dm_kcopyd_client *kc = job->kc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | |
Mikulas Patocka | 7383085 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 326 | if (job->pages) |
| 327 | kcopyd_put_pages(kc, job->pages); |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 328 | /* |
| 329 | * If this is the master job, the sub jobs have already |
| 330 | * completed so we can free everything. |
| 331 | */ |
| 332 | if (job->master_job == job) |
| 333 | mempool_free(job, kc->job_pool); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | fn(read_err, write_err, context); |
Alasdair G Kergon | 138728dc | 2006-03-27 01:17:50 -0800 | [diff] [blame] | 335 | |
| 336 | if (atomic_dec_and_test(&kc->nr_jobs)) |
| 337 | wake_up(&kc->destroyq); |
| 338 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | return 0; |
| 340 | } |
| 341 | |
| 342 | static void complete_io(unsigned long error, void *context) |
| 343 | { |
| 344 | struct kcopyd_job *job = (struct kcopyd_job *) context; |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 345 | struct dm_kcopyd_client *kc = job->kc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | |
| 347 | if (error) { |
| 348 | if (job->rw == WRITE) |
Jonathan Brassow | ce503f5 | 2006-06-26 00:27:30 -0700 | [diff] [blame] | 349 | job->write_err |= error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 350 | else |
| 351 | job->read_err = 1; |
| 352 | |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 353 | if (!test_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags)) { |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 354 | push(&kc->complete_jobs, job); |
| 355 | wake(kc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | return; |
| 357 | } |
| 358 | } |
| 359 | |
| 360 | if (job->rw == WRITE) |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 361 | push(&kc->complete_jobs, job); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | |
| 363 | else { |
| 364 | job->rw = WRITE; |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 365 | push(&kc->io_jobs, job); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 366 | } |
| 367 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 368 | wake(kc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 369 | } |
| 370 | |
| 371 | /* |
| 372 | * Request io on as many buffer heads as we can currently get for |
| 373 | * a particular job. |
| 374 | */ |
| 375 | static int run_io_job(struct kcopyd_job *job) |
| 376 | { |
| 377 | int r; |
Milan Broz | 373a392 | 2007-05-09 02:33:02 -0700 | [diff] [blame] | 378 | struct dm_io_request io_req = { |
Mikulas Patocka | 8d35d3e | 2011-01-13 19:59:50 +0000 | [diff] [blame] | 379 | .bi_rw = job->rw, |
Milan Broz | 373a392 | 2007-05-09 02:33:02 -0700 | [diff] [blame] | 380 | .mem.type = DM_IO_PAGE_LIST, |
| 381 | .mem.ptr.pl = job->pages, |
| 382 | .mem.offset = job->offset, |
| 383 | .notify.fn = complete_io, |
| 384 | .notify.context = job, |
| 385 | .client = job->kc->io_client, |
| 386 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | |
Jens Axboe | 7eaceac | 2011-03-10 08:52:07 +0100 | [diff] [blame] | 388 | if (job->rw == READ) |
Milan Broz | 373a392 | 2007-05-09 02:33:02 -0700 | [diff] [blame] | 389 | r = dm_io(&io_req, 1, &job->source, NULL); |
Jens Axboe | 721a960 | 2011-03-09 11:56:30 +0100 | [diff] [blame] | 390 | else |
Milan Broz | 373a392 | 2007-05-09 02:33:02 -0700 | [diff] [blame] | 391 | r = dm_io(&io_req, job->num_dests, job->dests, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 392 | |
| 393 | return r; |
| 394 | } |
| 395 | |
| 396 | static int run_pages_job(struct kcopyd_job *job) |
| 397 | { |
| 398 | int r; |
| 399 | |
| 400 | job->nr_pages = dm_div_up(job->dests[0].count + job->offset, |
| 401 | PAGE_SIZE >> 9); |
| 402 | r = kcopyd_get_pages(job->kc, job->nr_pages, &job->pages); |
| 403 | if (!r) { |
| 404 | /* this job is ready for io */ |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 405 | push(&job->kc->io_jobs, job); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | return 0; |
| 407 | } |
| 408 | |
| 409 | if (r == -ENOMEM) |
| 410 | /* can't complete now */ |
| 411 | return 1; |
| 412 | |
| 413 | return r; |
| 414 | } |
| 415 | |
| 416 | /* |
| 417 | * Run through a list for as long as possible. Returns the count |
| 418 | * of successful jobs. |
| 419 | */ |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 420 | static int process_jobs(struct list_head *jobs, struct dm_kcopyd_client *kc, |
| 421 | int (*fn) (struct kcopyd_job *)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | { |
| 423 | struct kcopyd_job *job; |
| 424 | int r, count = 0; |
| 425 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 426 | while ((job = pop(jobs, kc))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | |
| 428 | r = fn(job); |
| 429 | |
| 430 | if (r < 0) { |
| 431 | /* error this rogue job */ |
| 432 | if (job->rw == WRITE) |
Alasdair G Kergon | 4cdc1d1 | 2008-03-28 14:16:10 -0700 | [diff] [blame] | 433 | job->write_err = (unsigned long) -1L; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | else |
| 435 | job->read_err = 1; |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 436 | push(&kc->complete_jobs, job); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | break; |
| 438 | } |
| 439 | |
| 440 | if (r > 0) { |
| 441 | /* |
| 442 | * We couldn't service this job ATM, so |
| 443 | * push this job back onto the list. |
| 444 | */ |
Kazuo Ito | b673c3a | 2008-10-21 17:44:50 +0100 | [diff] [blame] | 445 | push_head(jobs, job); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | break; |
| 447 | } |
| 448 | |
| 449 | count++; |
| 450 | } |
| 451 | |
| 452 | return count; |
| 453 | } |
| 454 | |
| 455 | /* |
| 456 | * kcopyd does this every time it's woken up. |
| 457 | */ |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 458 | static void do_work(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 459 | { |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 460 | struct dm_kcopyd_client *kc = container_of(work, |
| 461 | struct dm_kcopyd_client, kcopyd_work); |
Jens Axboe | 7eaceac | 2011-03-10 08:52:07 +0100 | [diff] [blame] | 462 | struct blk_plug plug; |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 463 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | /* |
| 465 | * The order that these are called is *very* important. |
| 466 | * complete jobs can free some pages for pages jobs. |
| 467 | * Pages jobs when successful will jump onto the io jobs |
| 468 | * list. io jobs call wake when they complete and it all |
| 469 | * starts again. |
| 470 | */ |
Jens Axboe | 7eaceac | 2011-03-10 08:52:07 +0100 | [diff] [blame] | 471 | blk_start_plug(&plug); |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 472 | process_jobs(&kc->complete_jobs, kc, run_complete_job); |
| 473 | process_jobs(&kc->pages_jobs, kc, run_pages_job); |
| 474 | process_jobs(&kc->io_jobs, kc, run_io_job); |
Jens Axboe | 7eaceac | 2011-03-10 08:52:07 +0100 | [diff] [blame] | 475 | blk_finish_plug(&plug); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | } |
| 477 | |
| 478 | /* |
| 479 | * If we are copying a small region we just dispatch a single job |
| 480 | * to do the copy, otherwise the io has to be split up into many |
| 481 | * jobs. |
| 482 | */ |
| 483 | static void dispatch_job(struct kcopyd_job *job) |
| 484 | { |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 485 | struct dm_kcopyd_client *kc = job->kc; |
| 486 | atomic_inc(&kc->nr_jobs); |
Mikulas Patocka | 9ca170a | 2009-12-10 23:52:13 +0000 | [diff] [blame] | 487 | if (unlikely(!job->source.count)) |
| 488 | push(&kc->complete_jobs, job); |
| 489 | else |
| 490 | push(&kc->pages_jobs, job); |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 491 | wake(kc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 492 | } |
| 493 | |
Alasdair G Kergon | 4cdc1d1 | 2008-03-28 14:16:10 -0700 | [diff] [blame] | 494 | static void segment_complete(int read_err, unsigned long write_err, |
| 495 | void *context) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 496 | { |
| 497 | /* FIXME: tidy this function */ |
| 498 | sector_t progress = 0; |
| 499 | sector_t count = 0; |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 500 | struct kcopyd_job *sub_job = (struct kcopyd_job *) context; |
| 501 | struct kcopyd_job *job = sub_job->master_job; |
Mikulas Patocka | 7383085 | 2009-04-09 00:27:16 +0100 | [diff] [blame] | 502 | struct dm_kcopyd_client *kc = job->kc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 503 | |
Matthias Kaehlcke | def5b5b | 2007-10-19 22:38:52 +0100 | [diff] [blame] | 504 | mutex_lock(&job->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | |
| 506 | /* update the error */ |
| 507 | if (read_err) |
| 508 | job->read_err = 1; |
| 509 | |
| 510 | if (write_err) |
Jonathan Brassow | ce503f5 | 2006-06-26 00:27:30 -0700 | [diff] [blame] | 511 | job->write_err |= write_err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 512 | |
| 513 | /* |
| 514 | * Only dispatch more work if there hasn't been an error. |
| 515 | */ |
| 516 | if ((!job->read_err && !job->write_err) || |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 517 | test_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | /* get the next chunk of work */ |
| 519 | progress = job->progress; |
| 520 | count = job->source.count - progress; |
| 521 | if (count) { |
| 522 | if (count > SUB_JOB_SIZE) |
| 523 | count = SUB_JOB_SIZE; |
| 524 | |
| 525 | job->progress += count; |
| 526 | } |
| 527 | } |
Matthias Kaehlcke | def5b5b | 2007-10-19 22:38:52 +0100 | [diff] [blame] | 528 | mutex_unlock(&job->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 529 | |
| 530 | if (count) { |
| 531 | int i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | |
| 533 | *sub_job = *job; |
| 534 | sub_job->source.sector += progress; |
| 535 | sub_job->source.count = count; |
| 536 | |
| 537 | for (i = 0; i < job->num_dests; i++) { |
| 538 | sub_job->dests[i].sector += progress; |
| 539 | sub_job->dests[i].count = count; |
| 540 | } |
| 541 | |
| 542 | sub_job->fn = segment_complete; |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 543 | sub_job->context = sub_job; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | dispatch_job(sub_job); |
| 545 | |
| 546 | } else if (atomic_dec_and_test(&job->sub_jobs)) { |
| 547 | |
| 548 | /* |
Mikulas Patocka | 340cd44 | 2009-04-09 00:27:17 +0100 | [diff] [blame] | 549 | * Queue the completion callback to the kcopyd thread. |
| 550 | * |
| 551 | * Some callers assume that all the completions are called |
| 552 | * from a single thread and don't race with each other. |
| 553 | * |
| 554 | * We must not call the callback directly here because this |
| 555 | * code may not be executing in the thread. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 556 | */ |
Mikulas Patocka | 340cd44 | 2009-04-09 00:27:17 +0100 | [diff] [blame] | 557 | push(&kc->complete_jobs, job); |
| 558 | wake(kc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 559 | } |
| 560 | } |
| 561 | |
| 562 | /* |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 563 | * Create some sub jobs to share the work between them. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 564 | */ |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 565 | static void split_job(struct kcopyd_job *master_job) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | { |
| 567 | int i; |
| 568 | |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 569 | atomic_inc(&master_job->kc->nr_jobs); |
Mikulas Patocka | 340cd44 | 2009-04-09 00:27:17 +0100 | [diff] [blame] | 570 | |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 571 | atomic_set(&master_job->sub_jobs, SPLIT_COUNT); |
| 572 | for (i = 0; i < SPLIT_COUNT; i++) { |
| 573 | master_job[i + 1].master_job = master_job; |
| 574 | segment_complete(0, 0u, &master_job[i + 1]); |
| 575 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 576 | } |
| 577 | |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 578 | int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from, |
| 579 | unsigned int num_dests, struct dm_io_region *dests, |
| 580 | unsigned int flags, dm_kcopyd_notify_fn fn, void *context) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 581 | { |
| 582 | struct kcopyd_job *job; |
| 583 | |
| 584 | /* |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 585 | * Allocate an array of jobs consisting of one master job |
| 586 | * followed by SPLIT_COUNT sub jobs. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | */ |
Mikulas Patocka | 08d8757 | 2008-04-24 21:43:46 +0100 | [diff] [blame] | 588 | job = mempool_alloc(kc->job_pool, GFP_NOIO); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | |
| 590 | /* |
| 591 | * set up for the read. |
| 592 | */ |
| 593 | job->kc = kc; |
| 594 | job->flags = flags; |
| 595 | job->read_err = 0; |
| 596 | job->write_err = 0; |
| 597 | job->rw = READ; |
| 598 | |
| 599 | job->source = *from; |
| 600 | |
| 601 | job->num_dests = num_dests; |
| 602 | memcpy(&job->dests, dests, sizeof(*dests) * num_dests); |
| 603 | |
| 604 | job->offset = 0; |
| 605 | job->nr_pages = 0; |
| 606 | job->pages = NULL; |
| 607 | |
| 608 | job->fn = fn; |
| 609 | job->context = context; |
Mikulas Patocka | c6ea41f | 2011-05-29 13:03:00 +0100 | [diff] [blame] | 610 | job->master_job = job; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | |
Mikulas Patocka | a705a34 | 2011-05-29 13:02:58 +0100 | [diff] [blame] | 612 | if (job->source.count <= SUB_JOB_SIZE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 613 | dispatch_job(job); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 614 | else { |
Matthias Kaehlcke | def5b5b | 2007-10-19 22:38:52 +0100 | [diff] [blame] | 615 | mutex_init(&job->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | job->progress = 0; |
| 617 | split_job(job); |
| 618 | } |
| 619 | |
| 620 | return 0; |
| 621 | } |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 622 | EXPORT_SYMBOL(dm_kcopyd_copy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | |
| 624 | /* |
| 625 | * Cancels a kcopyd job, eg. someone might be deactivating a |
| 626 | * mirror. |
| 627 | */ |
Adrian Bunk | 0b56306 | 2006-01-06 00:20:08 -0800 | [diff] [blame] | 628 | #if 0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | int kcopyd_cancel(struct kcopyd_job *job, int block) |
| 630 | { |
| 631 | /* FIXME: finish */ |
| 632 | return -1; |
| 633 | } |
Adrian Bunk | 0b56306 | 2006-01-06 00:20:08 -0800 | [diff] [blame] | 634 | #endif /* 0 */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | |
| 636 | /*----------------------------------------------------------------- |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 637 | * Client setup |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | *---------------------------------------------------------------*/ |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 639 | int dm_kcopyd_client_create(unsigned min_pages, |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 640 | struct dm_kcopyd_client **result) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | { |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 642 | int r = -ENOMEM; |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 643 | struct dm_kcopyd_client *kc; |
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 | kc = kmalloc(sizeof(*kc), GFP_KERNEL); |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 646 | if (!kc) |
| 647 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 648 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 649 | spin_lock_init(&kc->job_lock); |
| 650 | INIT_LIST_HEAD(&kc->complete_jobs); |
| 651 | INIT_LIST_HEAD(&kc->io_jobs); |
| 652 | INIT_LIST_HEAD(&kc->pages_jobs); |
| 653 | |
Mikulas Patocka | 08d8757 | 2008-04-24 21:43:46 +0100 | [diff] [blame] | 654 | kc->job_pool = mempool_create_slab_pool(MIN_JOBS, _job_cache); |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 655 | if (!kc->job_pool) |
| 656 | goto bad_slab; |
Mikulas Patocka | 08d8757 | 2008-04-24 21:43:46 +0100 | [diff] [blame] | 657 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 658 | INIT_WORK(&kc->kcopyd_work, do_work); |
Tejun Heo | 9c4376d | 2011-01-13 19:59:58 +0000 | [diff] [blame] | 659 | kc->kcopyd_wq = alloc_workqueue("kcopyd", |
| 660 | WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0); |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 661 | if (!kc->kcopyd_wq) |
| 662 | goto bad_workqueue; |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 663 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | kc->pages = NULL; |
Mikulas Patocka | d047145 | 2011-05-29 13:03:07 +0100 | [diff] [blame] | 665 | kc->nr_reserved_pages = kc->nr_free_pages = 0; |
| 666 | r = client_reserve_pages(kc, min_pages); |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 667 | if (r) |
| 668 | goto bad_client_pages; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | |
Mikulas Patocka | bda8efe | 2011-05-29 13:03:09 +0100 | [diff] [blame^] | 670 | kc->io_client = dm_io_client_create(); |
Milan Broz | 373a392 | 2007-05-09 02:33:02 -0700 | [diff] [blame] | 671 | if (IS_ERR(kc->io_client)) { |
| 672 | r = PTR_ERR(kc->io_client); |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 673 | goto bad_io_client; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 674 | } |
| 675 | |
Alasdair G Kergon | 138728dc | 2006-03-27 01:17:50 -0800 | [diff] [blame] | 676 | init_waitqueue_head(&kc->destroyq); |
| 677 | atomic_set(&kc->nr_jobs, 0); |
| 678 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 679 | *result = kc; |
| 680 | return 0; |
Mikulas Patocka | 945fa4d | 2008-04-24 21:43:49 +0100 | [diff] [blame] | 681 | |
| 682 | bad_io_client: |
| 683 | client_free_pages(kc); |
| 684 | bad_client_pages: |
| 685 | destroy_workqueue(kc->kcopyd_wq); |
| 686 | bad_workqueue: |
| 687 | mempool_destroy(kc->job_pool); |
| 688 | bad_slab: |
| 689 | kfree(kc); |
| 690 | |
| 691 | return r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | } |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 693 | EXPORT_SYMBOL(dm_kcopyd_client_create); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 694 | |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 695 | void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | { |
Alasdair G Kergon | 138728dc | 2006-03-27 01:17:50 -0800 | [diff] [blame] | 697 | /* Wait for completion of all jobs submitted by this client. */ |
| 698 | wait_event(kc->destroyq, !atomic_read(&kc->nr_jobs)); |
| 699 | |
Mikulas Patocka | 8c0cbc2 | 2008-04-24 21:43:44 +0100 | [diff] [blame] | 700 | BUG_ON(!list_empty(&kc->complete_jobs)); |
| 701 | BUG_ON(!list_empty(&kc->io_jobs)); |
| 702 | BUG_ON(!list_empty(&kc->pages_jobs)); |
| 703 | destroy_workqueue(kc->kcopyd_wq); |
Milan Broz | 373a392 | 2007-05-09 02:33:02 -0700 | [diff] [blame] | 704 | dm_io_client_destroy(kc->io_client); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | client_free_pages(kc); |
Mikulas Patocka | 08d8757 | 2008-04-24 21:43:46 +0100 | [diff] [blame] | 706 | mempool_destroy(kc->job_pool); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | kfree(kc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | } |
Heinz Mauelshagen | eb69aca | 2008-04-24 21:43:19 +0100 | [diff] [blame] | 709 | EXPORT_SYMBOL(dm_kcopyd_client_destroy); |