Christoph Hellwig | 8c16567 | 2019-04-30 14:42:39 -0400 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* |
Jens Axboe | 0fe2347 | 2006-09-04 15:41:16 +0200 | [diff] [blame] | 3 | * Copyright (C) 2001 Jens Axboe <axboe@kernel.dk> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | */ |
| 5 | #include <linux/mm.h> |
| 6 | #include <linux/swap.h> |
| 7 | #include <linux/bio.h> |
| 8 | #include <linux/blkdev.h> |
Kent Overstreet | a27bb33 | 2013-05-07 16:19:08 -0700 | [diff] [blame] | 9 | #include <linux/uio.h> |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 10 | #include <linux/iocontext.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/slab.h> |
| 12 | #include <linux/init.h> |
| 13 | #include <linux/kernel.h> |
Paul Gortmaker | 630d9c4 | 2011-11-16 23:57:37 -0500 | [diff] [blame] | 14 | #include <linux/export.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/mempool.h> |
| 16 | #include <linux/workqueue.h> |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 17 | #include <linux/cgroup.h> |
Josef Bacik | 08e18ea | 2018-07-03 11:14:50 -0400 | [diff] [blame] | 18 | #include <linux/blk-cgroup.h> |
Damien Le Moal | b4c5875 | 2019-07-01 14:09:15 +0900 | [diff] [blame] | 19 | #include <linux/highmem.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | |
Li Zefan | 5578213 | 2009-06-09 13:43:05 +0800 | [diff] [blame] | 21 | #include <trace/events/block.h> |
Shaohua Li | 9e234ee | 2017-03-27 10:51:41 -0700 | [diff] [blame] | 22 | #include "blk.h" |
Josef Bacik | 67b42d0 | 2018-07-03 11:15:00 -0400 | [diff] [blame] | 23 | #include "blk-rq-qos.h" |
Ingo Molnar | 0bfc245 | 2008-11-26 11:59:56 +0100 | [diff] [blame] | 24 | |
Jens Axboe | 392ddc3 | 2008-12-23 12:42:54 +0100 | [diff] [blame] | 25 | /* |
| 26 | * Test patch to inline a certain number of bi_io_vec's inside the bio |
| 27 | * itself, to shrink a bio data allocation from two mempool calls to one |
| 28 | */ |
| 29 | #define BIO_INLINE_VECS 4 |
| 30 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | /* |
| 32 | * if you change this list, also change bvec_alloc or things will |
| 33 | * break badly! cannot be bigger than what you can fit into an |
| 34 | * unsigned short |
| 35 | */ |
Mikulas Patocka | bd5c4fa | 2018-03-21 12:49:29 -0400 | [diff] [blame] | 36 | #define BV(x, n) { .nr_vecs = x, .name = "biovec-"#n } |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 37 | static struct biovec_slab bvec_slabs[BVEC_POOL_NR] __read_mostly = { |
Mikulas Patocka | bd5c4fa | 2018-03-21 12:49:29 -0400 | [diff] [blame] | 38 | BV(1, 1), BV(4, 4), BV(16, 16), BV(64, 64), BV(128, 128), BV(BIO_MAX_PAGES, max), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | }; |
| 40 | #undef BV |
| 41 | |
| 42 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | * fs_bio_set is the bio_set containing bio and iovec memory pools used by |
| 44 | * IO code that does not need private memory pools. |
| 45 | */ |
Kent Overstreet | f4f8154 | 2018-05-08 21:33:52 -0400 | [diff] [blame] | 46 | struct bio_set fs_bio_set; |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 47 | EXPORT_SYMBOL(fs_bio_set); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 49 | /* |
| 50 | * Our slab pool management |
| 51 | */ |
| 52 | struct bio_slab { |
| 53 | struct kmem_cache *slab; |
| 54 | unsigned int slab_ref; |
| 55 | unsigned int slab_size; |
| 56 | char name[8]; |
| 57 | }; |
| 58 | static DEFINE_MUTEX(bio_slab_lock); |
| 59 | static struct bio_slab *bio_slabs; |
| 60 | static unsigned int bio_slab_nr, bio_slab_max; |
| 61 | |
| 62 | static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size) |
| 63 | { |
| 64 | unsigned int sz = sizeof(struct bio) + extra_size; |
| 65 | struct kmem_cache *slab = NULL; |
Alexey Khoroshilov | 389d7b2 | 2012-08-09 15:19:25 +0200 | [diff] [blame] | 66 | struct bio_slab *bslab, *new_bio_slabs; |
Anna Leuschner | 386bc35 | 2012-10-22 21:53:36 +0200 | [diff] [blame] | 67 | unsigned int new_bio_slab_max; |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 68 | unsigned int i, entry = -1; |
| 69 | |
| 70 | mutex_lock(&bio_slab_lock); |
| 71 | |
| 72 | i = 0; |
| 73 | while (i < bio_slab_nr) { |
Thiago Farina | f06f135 | 2010-01-19 14:07:09 +0100 | [diff] [blame] | 74 | bslab = &bio_slabs[i]; |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 75 | |
| 76 | if (!bslab->slab && entry == -1) |
| 77 | entry = i; |
| 78 | else if (bslab->slab_size == sz) { |
| 79 | slab = bslab->slab; |
| 80 | bslab->slab_ref++; |
| 81 | break; |
| 82 | } |
| 83 | i++; |
| 84 | } |
| 85 | |
| 86 | if (slab) |
| 87 | goto out_unlock; |
| 88 | |
| 89 | if (bio_slab_nr == bio_slab_max && entry == -1) { |
Anna Leuschner | 386bc35 | 2012-10-22 21:53:36 +0200 | [diff] [blame] | 90 | new_bio_slab_max = bio_slab_max << 1; |
Alexey Khoroshilov | 389d7b2 | 2012-08-09 15:19:25 +0200 | [diff] [blame] | 91 | new_bio_slabs = krealloc(bio_slabs, |
Anna Leuschner | 386bc35 | 2012-10-22 21:53:36 +0200 | [diff] [blame] | 92 | new_bio_slab_max * sizeof(struct bio_slab), |
Alexey Khoroshilov | 389d7b2 | 2012-08-09 15:19:25 +0200 | [diff] [blame] | 93 | GFP_KERNEL); |
| 94 | if (!new_bio_slabs) |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 95 | goto out_unlock; |
Anna Leuschner | 386bc35 | 2012-10-22 21:53:36 +0200 | [diff] [blame] | 96 | bio_slab_max = new_bio_slab_max; |
Alexey Khoroshilov | 389d7b2 | 2012-08-09 15:19:25 +0200 | [diff] [blame] | 97 | bio_slabs = new_bio_slabs; |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 98 | } |
| 99 | if (entry == -1) |
| 100 | entry = bio_slab_nr++; |
| 101 | |
| 102 | bslab = &bio_slabs[entry]; |
| 103 | |
| 104 | snprintf(bslab->name, sizeof(bslab->name), "bio-%d", entry); |
Mikulas Patocka | 6a24148 | 2014-03-28 15:51:55 -0400 | [diff] [blame] | 105 | slab = kmem_cache_create(bslab->name, sz, ARCH_KMALLOC_MINALIGN, |
| 106 | SLAB_HWCACHE_ALIGN, NULL); |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 107 | if (!slab) |
| 108 | goto out_unlock; |
| 109 | |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 110 | bslab->slab = slab; |
| 111 | bslab->slab_ref = 1; |
| 112 | bslab->slab_size = sz; |
| 113 | out_unlock: |
| 114 | mutex_unlock(&bio_slab_lock); |
| 115 | return slab; |
| 116 | } |
| 117 | |
| 118 | static void bio_put_slab(struct bio_set *bs) |
| 119 | { |
| 120 | struct bio_slab *bslab = NULL; |
| 121 | unsigned int i; |
| 122 | |
| 123 | mutex_lock(&bio_slab_lock); |
| 124 | |
| 125 | for (i = 0; i < bio_slab_nr; i++) { |
| 126 | if (bs->bio_slab == bio_slabs[i].slab) { |
| 127 | bslab = &bio_slabs[i]; |
| 128 | break; |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | if (WARN(!bslab, KERN_ERR "bio: unable to find slab!\n")) |
| 133 | goto out; |
| 134 | |
| 135 | WARN_ON(!bslab->slab_ref); |
| 136 | |
| 137 | if (--bslab->slab_ref) |
| 138 | goto out; |
| 139 | |
| 140 | kmem_cache_destroy(bslab->slab); |
| 141 | bslab->slab = NULL; |
| 142 | |
| 143 | out: |
| 144 | mutex_unlock(&bio_slab_lock); |
| 145 | } |
| 146 | |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 147 | unsigned int bvec_nr_vecs(unsigned short idx) |
| 148 | { |
Greg Edwards | d6c02a9 | 2018-08-08 13:27:53 -0600 | [diff] [blame] | 149 | return bvec_slabs[--idx].nr_vecs; |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 150 | } |
| 151 | |
Kent Overstreet | 9f060e2 | 2012-10-12 15:29:33 -0700 | [diff] [blame] | 152 | void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned int idx) |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 153 | { |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 154 | if (!idx) |
| 155 | return; |
| 156 | idx--; |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 157 | |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 158 | BIO_BUG_ON(idx >= BVEC_POOL_NR); |
| 159 | |
| 160 | if (idx == BVEC_POOL_MAX) { |
Kent Overstreet | 9f060e2 | 2012-10-12 15:29:33 -0700 | [diff] [blame] | 161 | mempool_free(bv, pool); |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 162 | } else { |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 163 | struct biovec_slab *bvs = bvec_slabs + idx; |
| 164 | |
| 165 | kmem_cache_free(bvs->slab, bv); |
| 166 | } |
| 167 | } |
| 168 | |
Kent Overstreet | 9f060e2 | 2012-10-12 15:29:33 -0700 | [diff] [blame] | 169 | struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx, |
| 170 | mempool_t *pool) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | { |
| 172 | struct bio_vec *bvl; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | |
| 174 | /* |
Jens Axboe | 7ff9345 | 2008-12-11 11:53:43 +0100 | [diff] [blame] | 175 | * see comment near bvec_array define! |
| 176 | */ |
| 177 | switch (nr) { |
| 178 | case 1: |
| 179 | *idx = 0; |
| 180 | break; |
| 181 | case 2 ... 4: |
| 182 | *idx = 1; |
| 183 | break; |
| 184 | case 5 ... 16: |
| 185 | *idx = 2; |
| 186 | break; |
| 187 | case 17 ... 64: |
| 188 | *idx = 3; |
| 189 | break; |
| 190 | case 65 ... 128: |
| 191 | *idx = 4; |
| 192 | break; |
| 193 | case 129 ... BIO_MAX_PAGES: |
| 194 | *idx = 5; |
| 195 | break; |
| 196 | default: |
| 197 | return NULL; |
| 198 | } |
| 199 | |
| 200 | /* |
| 201 | * idx now points to the pool we want to allocate from. only the |
| 202 | * 1-vec entry pool is mempool backed. |
| 203 | */ |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 204 | if (*idx == BVEC_POOL_MAX) { |
Jens Axboe | 7ff9345 | 2008-12-11 11:53:43 +0100 | [diff] [blame] | 205 | fallback: |
Kent Overstreet | 9f060e2 | 2012-10-12 15:29:33 -0700 | [diff] [blame] | 206 | bvl = mempool_alloc(pool, gfp_mask); |
Jens Axboe | 7ff9345 | 2008-12-11 11:53:43 +0100 | [diff] [blame] | 207 | } else { |
| 208 | struct biovec_slab *bvs = bvec_slabs + *idx; |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 209 | gfp_t __gfp_mask = gfp_mask & ~(__GFP_DIRECT_RECLAIM | __GFP_IO); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | |
Jens Axboe | 0a0d96b | 2008-09-11 13:17:37 +0200 | [diff] [blame] | 211 | /* |
Jens Axboe | 7ff9345 | 2008-12-11 11:53:43 +0100 | [diff] [blame] | 212 | * Make this allocation restricted and don't dump info on |
| 213 | * allocation failures, since we'll fallback to the mempool |
| 214 | * in case of failure. |
Jens Axboe | 0a0d96b | 2008-09-11 13:17:37 +0200 | [diff] [blame] | 215 | */ |
Jens Axboe | 7ff9345 | 2008-12-11 11:53:43 +0100 | [diff] [blame] | 216 | __gfp_mask |= __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN; |
| 217 | |
| 218 | /* |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 219 | * Try a slab allocation. If this fails and __GFP_DIRECT_RECLAIM |
Jens Axboe | 7ff9345 | 2008-12-11 11:53:43 +0100 | [diff] [blame] | 220 | * is set, retry with the 1-entry mempool |
| 221 | */ |
| 222 | bvl = kmem_cache_alloc(bvs->slab, __gfp_mask); |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 223 | if (unlikely(!bvl && (gfp_mask & __GFP_DIRECT_RECLAIM))) { |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 224 | *idx = BVEC_POOL_MAX; |
Jens Axboe | 7ff9345 | 2008-12-11 11:53:43 +0100 | [diff] [blame] | 225 | goto fallback; |
| 226 | } |
| 227 | } |
| 228 | |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 229 | (*idx)++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | return bvl; |
| 231 | } |
| 232 | |
Jens Axboe | 9ae3b3f5 | 2017-06-28 15:30:13 -0600 | [diff] [blame] | 233 | void bio_uninit(struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | { |
Dennis Zhou | 6f70fb6 | 2018-12-05 12:10:37 -0500 | [diff] [blame] | 235 | bio_disassociate_blkg(bio); |
Justin Tee | ece841a | 2019-12-05 10:09:01 +0800 | [diff] [blame] | 236 | |
| 237 | if (bio_integrity(bio)) |
| 238 | bio_integrity_free(bio); |
Kent Overstreet | 4254bba | 2012-09-06 15:35:00 -0700 | [diff] [blame] | 239 | } |
Jens Axboe | 9ae3b3f5 | 2017-06-28 15:30:13 -0600 | [diff] [blame] | 240 | EXPORT_SYMBOL(bio_uninit); |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 241 | |
Kent Overstreet | 4254bba | 2012-09-06 15:35:00 -0700 | [diff] [blame] | 242 | static void bio_free(struct bio *bio) |
| 243 | { |
| 244 | struct bio_set *bs = bio->bi_pool; |
| 245 | void *p; |
| 246 | |
Jens Axboe | 9ae3b3f5 | 2017-06-28 15:30:13 -0600 | [diff] [blame] | 247 | bio_uninit(bio); |
Kent Overstreet | 4254bba | 2012-09-06 15:35:00 -0700 | [diff] [blame] | 248 | |
| 249 | if (bs) { |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 250 | bvec_free(&bs->bvec_pool, bio->bi_io_vec, BVEC_POOL_IDX(bio)); |
Kent Overstreet | 4254bba | 2012-09-06 15:35:00 -0700 | [diff] [blame] | 251 | |
| 252 | /* |
| 253 | * If we have front padding, adjust the bio pointer before freeing |
| 254 | */ |
| 255 | p = bio; |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 256 | p -= bs->front_pad; |
| 257 | |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 258 | mempool_free(p, &bs->bio_pool); |
Kent Overstreet | 4254bba | 2012-09-06 15:35:00 -0700 | [diff] [blame] | 259 | } else { |
| 260 | /* Bio was allocated by bio_kmalloc() */ |
| 261 | kfree(bio); |
| 262 | } |
Peter Osterlund | 3676347 | 2005-09-06 15:16:42 -0700 | [diff] [blame] | 263 | } |
| 264 | |
Jens Axboe | 9ae3b3f5 | 2017-06-28 15:30:13 -0600 | [diff] [blame] | 265 | /* |
| 266 | * Users of this function have their own bio allocation. Subsequently, |
| 267 | * they must remember to pair any call to bio_init() with bio_uninit() |
| 268 | * when IO has completed, or when the bio is released. |
| 269 | */ |
Ming Lei | 3a83f46 | 2016-11-22 08:57:21 -0700 | [diff] [blame] | 270 | void bio_init(struct bio *bio, struct bio_vec *table, |
| 271 | unsigned short max_vecs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | { |
Jens Axboe | 2b94de5 | 2007-07-18 13:14:03 +0200 | [diff] [blame] | 273 | memset(bio, 0, sizeof(*bio)); |
Jens Axboe | c4cf526 | 2015-04-17 16:15:18 -0600 | [diff] [blame] | 274 | atomic_set(&bio->__bi_remaining, 1); |
Jens Axboe | dac5621 | 2015-04-17 16:23:59 -0600 | [diff] [blame] | 275 | atomic_set(&bio->__bi_cnt, 1); |
Ming Lei | 3a83f46 | 2016-11-22 08:57:21 -0700 | [diff] [blame] | 276 | |
| 277 | bio->bi_io_vec = table; |
| 278 | bio->bi_max_vecs = max_vecs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | } |
H Hartley Sweeten | a112a71 | 2009-09-26 16:19:21 +0200 | [diff] [blame] | 280 | EXPORT_SYMBOL(bio_init); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | |
| 282 | /** |
Kent Overstreet | f44b48c | 2012-09-06 15:34:58 -0700 | [diff] [blame] | 283 | * bio_reset - reinitialize a bio |
| 284 | * @bio: bio to reset |
| 285 | * |
| 286 | * Description: |
| 287 | * After calling bio_reset(), @bio will be in the same state as a freshly |
| 288 | * allocated bio returned bio bio_alloc_bioset() - the only fields that are |
| 289 | * preserved are the ones that are initialized by bio_alloc_bioset(). See |
| 290 | * comment in struct bio. |
| 291 | */ |
| 292 | void bio_reset(struct bio *bio) |
| 293 | { |
| 294 | unsigned long flags = bio->bi_flags & (~0UL << BIO_RESET_BITS); |
| 295 | |
Jens Axboe | 9ae3b3f5 | 2017-06-28 15:30:13 -0600 | [diff] [blame] | 296 | bio_uninit(bio); |
Kent Overstreet | f44b48c | 2012-09-06 15:34:58 -0700 | [diff] [blame] | 297 | |
| 298 | memset(bio, 0, BIO_RESET_BYTES); |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 299 | bio->bi_flags = flags; |
Jens Axboe | c4cf526 | 2015-04-17 16:15:18 -0600 | [diff] [blame] | 300 | atomic_set(&bio->__bi_remaining, 1); |
Kent Overstreet | f44b48c | 2012-09-06 15:34:58 -0700 | [diff] [blame] | 301 | } |
| 302 | EXPORT_SYMBOL(bio_reset); |
| 303 | |
Christoph Hellwig | 38f8baa | 2016-03-11 17:34:51 +0100 | [diff] [blame] | 304 | static struct bio *__bio_chain_endio(struct bio *bio) |
Kent Overstreet | 196d38bc | 2013-11-23 18:34:15 -0800 | [diff] [blame] | 305 | { |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 306 | struct bio *parent = bio->bi_private; |
| 307 | |
Christoph Hellwig | 4e4cbee | 2017-06-03 09:38:06 +0200 | [diff] [blame] | 308 | if (!parent->bi_status) |
| 309 | parent->bi_status = bio->bi_status; |
Kent Overstreet | 196d38bc | 2013-11-23 18:34:15 -0800 | [diff] [blame] | 310 | bio_put(bio); |
Christoph Hellwig | 38f8baa | 2016-03-11 17:34:51 +0100 | [diff] [blame] | 311 | return parent; |
| 312 | } |
| 313 | |
| 314 | static void bio_chain_endio(struct bio *bio) |
| 315 | { |
| 316 | bio_endio(__bio_chain_endio(bio)); |
Kent Overstreet | 196d38bc | 2013-11-23 18:34:15 -0800 | [diff] [blame] | 317 | } |
| 318 | |
| 319 | /** |
| 320 | * bio_chain - chain bio completions |
Randy Dunlap | 1051a90 | 2014-04-20 16:03:31 -0700 | [diff] [blame] | 321 | * @bio: the target bio |
| 322 | * @parent: the @bio's parent bio |
Kent Overstreet | 196d38bc | 2013-11-23 18:34:15 -0800 | [diff] [blame] | 323 | * |
| 324 | * The caller won't have a bi_end_io called when @bio completes - instead, |
| 325 | * @parent's bi_end_io won't be called until both @parent and @bio have |
| 326 | * completed; the chained bio will also be freed when it completes. |
| 327 | * |
| 328 | * The caller must not set bi_private or bi_end_io in @bio. |
| 329 | */ |
| 330 | void bio_chain(struct bio *bio, struct bio *parent) |
| 331 | { |
| 332 | BUG_ON(bio->bi_private || bio->bi_end_io); |
| 333 | |
| 334 | bio->bi_private = parent; |
| 335 | bio->bi_end_io = bio_chain_endio; |
Jens Axboe | c4cf526 | 2015-04-17 16:15:18 -0600 | [diff] [blame] | 336 | bio_inc_remaining(parent); |
Kent Overstreet | 196d38bc | 2013-11-23 18:34:15 -0800 | [diff] [blame] | 337 | } |
| 338 | EXPORT_SYMBOL(bio_chain); |
| 339 | |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 340 | static void bio_alloc_rescue(struct work_struct *work) |
| 341 | { |
| 342 | struct bio_set *bs = container_of(work, struct bio_set, rescue_work); |
| 343 | struct bio *bio; |
| 344 | |
| 345 | while (1) { |
| 346 | spin_lock(&bs->rescue_lock); |
| 347 | bio = bio_list_pop(&bs->rescue_list); |
| 348 | spin_unlock(&bs->rescue_lock); |
| 349 | |
| 350 | if (!bio) |
| 351 | break; |
| 352 | |
| 353 | generic_make_request(bio); |
| 354 | } |
| 355 | } |
| 356 | |
| 357 | static void punt_bios_to_rescuer(struct bio_set *bs) |
| 358 | { |
| 359 | struct bio_list punt, nopunt; |
| 360 | struct bio *bio; |
| 361 | |
NeilBrown | 47e0fb4 | 2017-06-18 14:38:57 +1000 | [diff] [blame] | 362 | if (WARN_ON_ONCE(!bs->rescue_workqueue)) |
| 363 | return; |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 364 | /* |
| 365 | * In order to guarantee forward progress we must punt only bios that |
| 366 | * were allocated from this bio_set; otherwise, if there was a bio on |
| 367 | * there for a stacking driver higher up in the stack, processing it |
| 368 | * could require allocating bios from this bio_set, and doing that from |
| 369 | * our own rescuer would be bad. |
| 370 | * |
| 371 | * Since bio lists are singly linked, pop them all instead of trying to |
| 372 | * remove from the middle of the list: |
| 373 | */ |
| 374 | |
| 375 | bio_list_init(&punt); |
| 376 | bio_list_init(&nopunt); |
| 377 | |
NeilBrown | f5fe1b5 | 2017-03-10 17:00:47 +1100 | [diff] [blame] | 378 | while ((bio = bio_list_pop(¤t->bio_list[0]))) |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 379 | bio_list_add(bio->bi_pool == bs ? &punt : &nopunt, bio); |
NeilBrown | f5fe1b5 | 2017-03-10 17:00:47 +1100 | [diff] [blame] | 380 | current->bio_list[0] = nopunt; |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 381 | |
NeilBrown | f5fe1b5 | 2017-03-10 17:00:47 +1100 | [diff] [blame] | 382 | bio_list_init(&nopunt); |
| 383 | while ((bio = bio_list_pop(¤t->bio_list[1]))) |
| 384 | bio_list_add(bio->bi_pool == bs ? &punt : &nopunt, bio); |
| 385 | current->bio_list[1] = nopunt; |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 386 | |
| 387 | spin_lock(&bs->rescue_lock); |
| 388 | bio_list_merge(&bs->rescue_list, &punt); |
| 389 | spin_unlock(&bs->rescue_lock); |
| 390 | |
| 391 | queue_work(bs->rescue_workqueue, &bs->rescue_work); |
| 392 | } |
| 393 | |
Kent Overstreet | f44b48c | 2012-09-06 15:34:58 -0700 | [diff] [blame] | 394 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | * bio_alloc_bioset - allocate a bio for I/O |
Randy Dunlap | 519c8e9 | 2017-10-16 11:01:00 -0700 | [diff] [blame] | 396 | * @gfp_mask: the GFP_* mask given to the slab allocator |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | * @nr_iovecs: number of iovecs to pre-allocate |
Jaak Ristioja | db18efa | 2010-01-15 12:05:07 +0200 | [diff] [blame] | 398 | * @bs: the bio_set to allocate from. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 399 | * |
| 400 | * Description: |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 401 | * If @bs is NULL, uses kmalloc() to allocate the bio; else the allocation is |
| 402 | * backed by the @bs's mempool. |
| 403 | * |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 404 | * When @bs is not NULL, if %__GFP_DIRECT_RECLAIM is set then bio_alloc will |
| 405 | * always be able to allocate a bio. This is due to the mempool guarantees. |
| 406 | * To make this work, callers must never allocate more than 1 bio at a time |
| 407 | * from this pool. Callers that need to allocate more than 1 bio must always |
| 408 | * submit the previously allocated bio for IO before attempting to allocate |
| 409 | * a new one. Failure to do so can cause deadlocks under memory pressure. |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 410 | * |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 411 | * Note that when running under generic_make_request() (i.e. any block |
| 412 | * driver), bios are not submitted until after you return - see the code in |
| 413 | * generic_make_request() that converts recursion into iteration, to prevent |
| 414 | * stack overflows. |
| 415 | * |
| 416 | * This would normally mean allocating multiple bios under |
| 417 | * generic_make_request() would be susceptible to deadlocks, but we have |
| 418 | * deadlock avoidance code that resubmits any blocked bios from a rescuer |
| 419 | * thread. |
| 420 | * |
| 421 | * However, we do not guarantee forward progress for allocations from other |
| 422 | * mempools. Doing multiple allocations from the same mempool under |
| 423 | * generic_make_request() should be avoided - instead, use bio_set's front_pad |
| 424 | * for per bio allocations. |
| 425 | * |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 426 | * RETURNS: |
| 427 | * Pointer to new bio on success, NULL on failure. |
| 428 | */ |
Dan Carpenter | 7a88fa1 | 2017-03-23 13:24:55 +0300 | [diff] [blame] | 429 | struct bio *bio_alloc_bioset(gfp_t gfp_mask, unsigned int nr_iovecs, |
| 430 | struct bio_set *bs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | { |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 432 | gfp_t saved_gfp = gfp_mask; |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 433 | unsigned front_pad; |
| 434 | unsigned inline_vecs; |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 435 | struct bio_vec *bvl = NULL; |
Tejun Heo | 451a9eb | 2009-04-15 19:50:51 +0200 | [diff] [blame] | 436 | struct bio *bio; |
| 437 | void *p; |
Jens Axboe | 0a0d96b | 2008-09-11 13:17:37 +0200 | [diff] [blame] | 438 | |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 439 | if (!bs) { |
| 440 | if (nr_iovecs > UIO_MAXIOV) |
| 441 | return NULL; |
| 442 | |
| 443 | p = kmalloc(sizeof(struct bio) + |
| 444 | nr_iovecs * sizeof(struct bio_vec), |
| 445 | gfp_mask); |
| 446 | front_pad = 0; |
| 447 | inline_vecs = nr_iovecs; |
| 448 | } else { |
Junichi Nomura | d8f429e | 2014-10-03 17:27:12 -0400 | [diff] [blame] | 449 | /* should not use nobvec bioset for nr_iovecs > 0 */ |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 450 | if (WARN_ON_ONCE(!mempool_initialized(&bs->bvec_pool) && |
| 451 | nr_iovecs > 0)) |
Junichi Nomura | d8f429e | 2014-10-03 17:27:12 -0400 | [diff] [blame] | 452 | return NULL; |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 453 | /* |
| 454 | * generic_make_request() converts recursion to iteration; this |
| 455 | * means if we're running beneath it, any bios we allocate and |
| 456 | * submit will not be submitted (and thus freed) until after we |
| 457 | * return. |
| 458 | * |
| 459 | * This exposes us to a potential deadlock if we allocate |
| 460 | * multiple bios from the same bio_set() while running |
| 461 | * underneath generic_make_request(). If we were to allocate |
| 462 | * multiple bios (say a stacking block driver that was splitting |
| 463 | * bios), we would deadlock if we exhausted the mempool's |
| 464 | * reserve. |
| 465 | * |
| 466 | * We solve this, and guarantee forward progress, with a rescuer |
| 467 | * workqueue per bio_set. If we go to allocate and there are |
| 468 | * bios on current->bio_list, we first try the allocation |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 469 | * without __GFP_DIRECT_RECLAIM; if that fails, we punt those |
| 470 | * bios we would be blocking to the rescuer workqueue before |
| 471 | * we retry with the original gfp_flags. |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 472 | */ |
| 473 | |
NeilBrown | f5fe1b5 | 2017-03-10 17:00:47 +1100 | [diff] [blame] | 474 | if (current->bio_list && |
| 475 | (!bio_list_empty(¤t->bio_list[0]) || |
NeilBrown | 47e0fb4 | 2017-06-18 14:38:57 +1000 | [diff] [blame] | 476 | !bio_list_empty(¤t->bio_list[1])) && |
| 477 | bs->rescue_workqueue) |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 478 | gfp_mask &= ~__GFP_DIRECT_RECLAIM; |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 479 | |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 480 | p = mempool_alloc(&bs->bio_pool, gfp_mask); |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 481 | if (!p && gfp_mask != saved_gfp) { |
| 482 | punt_bios_to_rescuer(bs); |
| 483 | gfp_mask = saved_gfp; |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 484 | p = mempool_alloc(&bs->bio_pool, gfp_mask); |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 485 | } |
| 486 | |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 487 | front_pad = bs->front_pad; |
| 488 | inline_vecs = BIO_INLINE_VECS; |
| 489 | } |
| 490 | |
Tejun Heo | 451a9eb | 2009-04-15 19:50:51 +0200 | [diff] [blame] | 491 | if (unlikely(!p)) |
| 492 | return NULL; |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 493 | |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 494 | bio = p + front_pad; |
Ming Lei | 3a83f46 | 2016-11-22 08:57:21 -0700 | [diff] [blame] | 495 | bio_init(bio, NULL, 0); |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 496 | |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 497 | if (nr_iovecs > inline_vecs) { |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 498 | unsigned long idx = 0; |
| 499 | |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 500 | bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx, &bs->bvec_pool); |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 501 | if (!bvl && gfp_mask != saved_gfp) { |
| 502 | punt_bios_to_rescuer(bs); |
| 503 | gfp_mask = saved_gfp; |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 504 | bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx, &bs->bvec_pool); |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 505 | } |
| 506 | |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 507 | if (unlikely(!bvl)) |
| 508 | goto err_free; |
Kent Overstreet | a38352e | 2012-05-25 13:03:11 -0700 | [diff] [blame] | 509 | |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 510 | bio->bi_flags |= idx << BVEC_POOL_OFFSET; |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 511 | } else if (nr_iovecs) { |
| 512 | bvl = bio->bi_inline_vecs; |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 513 | } |
Kent Overstreet | 3f86a82 | 2012-09-06 15:35:01 -0700 | [diff] [blame] | 514 | |
| 515 | bio->bi_pool = bs; |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 516 | bio->bi_max_vecs = nr_iovecs; |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 517 | bio->bi_io_vec = bvl; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | return bio; |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 519 | |
| 520 | err_free: |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 521 | mempool_free(p, &bs->bio_pool); |
Ingo Molnar | 3405397 | 2009-02-21 11:16:36 +0100 | [diff] [blame] | 522 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | } |
H Hartley Sweeten | a112a71 | 2009-09-26 16:19:21 +0200 | [diff] [blame] | 524 | EXPORT_SYMBOL(bio_alloc_bioset); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 525 | |
Kent Overstreet | 38a72da | 2018-05-08 21:33:53 -0400 | [diff] [blame] | 526 | void zero_fill_bio_iter(struct bio *bio, struct bvec_iter start) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 527 | { |
| 528 | unsigned long flags; |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 529 | struct bio_vec bv; |
| 530 | struct bvec_iter iter; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 531 | |
Kent Overstreet | 38a72da | 2018-05-08 21:33:53 -0400 | [diff] [blame] | 532 | __bio_for_each_segment(bv, bio, iter, start) { |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 533 | char *data = bvec_kmap_irq(&bv, &flags); |
| 534 | memset(data, 0, bv.bv_len); |
| 535 | flush_dcache_page(bv.bv_page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 536 | bvec_kunmap_irq(data, &flags); |
| 537 | } |
| 538 | } |
Kent Overstreet | 38a72da | 2018-05-08 21:33:53 -0400 | [diff] [blame] | 539 | EXPORT_SYMBOL(zero_fill_bio_iter); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 540 | |
Ming Lei | 85a8ce6 | 2019-12-28 07:05:48 +0800 | [diff] [blame^] | 541 | void bio_truncate(struct bio *bio, unsigned new_size) |
| 542 | { |
| 543 | struct bio_vec bv; |
| 544 | struct bvec_iter iter; |
| 545 | unsigned int done = 0; |
| 546 | bool truncated = false; |
| 547 | |
| 548 | if (new_size >= bio->bi_iter.bi_size) |
| 549 | return; |
| 550 | |
| 551 | if (bio_data_dir(bio) != READ) |
| 552 | goto exit; |
| 553 | |
| 554 | bio_for_each_segment(bv, bio, iter) { |
| 555 | if (done + bv.bv_len > new_size) { |
| 556 | unsigned offset; |
| 557 | |
| 558 | if (!truncated) |
| 559 | offset = new_size - done; |
| 560 | else |
| 561 | offset = 0; |
| 562 | zero_user(bv.bv_page, offset, bv.bv_len - offset); |
| 563 | truncated = true; |
| 564 | } |
| 565 | done += bv.bv_len; |
| 566 | } |
| 567 | |
| 568 | exit: |
| 569 | /* |
| 570 | * Don't touch bvec table here and make it really immutable, since |
| 571 | * fs bio user has to retrieve all pages via bio_for_each_segment_all |
| 572 | * in its .end_bio() callback. |
| 573 | * |
| 574 | * It is enough to truncate bio by updating .bi_size since we can make |
| 575 | * correct bvec with the updated .bi_size for drivers. |
| 576 | */ |
| 577 | bio->bi_iter.bi_size = new_size; |
| 578 | } |
| 579 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | /** |
| 581 | * bio_put - release a reference to a bio |
| 582 | * @bio: bio to release reference to |
| 583 | * |
| 584 | * Description: |
| 585 | * Put a reference to a &struct bio, either one you have gotten with |
NeilBrown | 9b10f6a | 2017-06-18 14:38:59 +1000 | [diff] [blame] | 586 | * bio_alloc, bio_get or bio_clone_*. The last put of a bio will free it. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | **/ |
| 588 | void bio_put(struct bio *bio) |
| 589 | { |
Jens Axboe | dac5621 | 2015-04-17 16:23:59 -0600 | [diff] [blame] | 590 | if (!bio_flagged(bio, BIO_REFFED)) |
Kent Overstreet | 4254bba | 2012-09-06 15:35:00 -0700 | [diff] [blame] | 591 | bio_free(bio); |
Jens Axboe | dac5621 | 2015-04-17 16:23:59 -0600 | [diff] [blame] | 592 | else { |
| 593 | BIO_BUG_ON(!atomic_read(&bio->__bi_cnt)); |
| 594 | |
| 595 | /* |
| 596 | * last put frees it |
| 597 | */ |
| 598 | if (atomic_dec_and_test(&bio->__bi_cnt)) |
| 599 | bio_free(bio); |
| 600 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 601 | } |
H Hartley Sweeten | a112a71 | 2009-09-26 16:19:21 +0200 | [diff] [blame] | 602 | EXPORT_SYMBOL(bio_put); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 603 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 604 | /** |
Kent Overstreet | 59d276f | 2013-11-23 18:19:27 -0800 | [diff] [blame] | 605 | * __bio_clone_fast - clone a bio that shares the original bio's biovec |
| 606 | * @bio: destination bio |
| 607 | * @bio_src: bio to clone |
| 608 | * |
| 609 | * Clone a &bio. Caller will own the returned bio, but not |
| 610 | * the actual data it points to. Reference count of returned |
| 611 | * bio will be one. |
| 612 | * |
| 613 | * Caller must ensure that @bio_src is not freed before @bio. |
| 614 | */ |
| 615 | void __bio_clone_fast(struct bio *bio, struct bio *bio_src) |
| 616 | { |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 617 | BUG_ON(bio->bi_pool && BVEC_POOL_IDX(bio)); |
Kent Overstreet | 59d276f | 2013-11-23 18:19:27 -0800 | [diff] [blame] | 618 | |
| 619 | /* |
Christoph Hellwig | 74d4699 | 2017-08-23 19:10:32 +0200 | [diff] [blame] | 620 | * most users will be overriding ->bi_disk with a new target, |
Kent Overstreet | 59d276f | 2013-11-23 18:19:27 -0800 | [diff] [blame] | 621 | * so we don't set nor calculate new physical/hw segment counts here |
| 622 | */ |
Christoph Hellwig | 74d4699 | 2017-08-23 19:10:32 +0200 | [diff] [blame] | 623 | bio->bi_disk = bio_src->bi_disk; |
Michael Lyle | 62530ed | 2017-11-16 23:47:25 -0800 | [diff] [blame] | 624 | bio->bi_partno = bio_src->bi_partno; |
Jens Axboe | b7c44ed | 2015-07-24 12:37:59 -0600 | [diff] [blame] | 625 | bio_set_flag(bio, BIO_CLONED); |
Shaohua Li | 111be88 | 2017-12-20 11:10:17 -0700 | [diff] [blame] | 626 | if (bio_flagged(bio_src, BIO_THROTTLED)) |
| 627 | bio_set_flag(bio, BIO_THROTTLED); |
Jens Axboe | 1eff9d3 | 2016-08-05 15:35:16 -0600 | [diff] [blame] | 628 | bio->bi_opf = bio_src->bi_opf; |
Hannes Reinecke | ca474b7 | 2018-11-12 10:35:25 -0700 | [diff] [blame] | 629 | bio->bi_ioprio = bio_src->bi_ioprio; |
Jens Axboe | cb6934f | 2017-06-27 09:22:02 -0600 | [diff] [blame] | 630 | bio->bi_write_hint = bio_src->bi_write_hint; |
Kent Overstreet | 59d276f | 2013-11-23 18:19:27 -0800 | [diff] [blame] | 631 | bio->bi_iter = bio_src->bi_iter; |
| 632 | bio->bi_io_vec = bio_src->bi_io_vec; |
Paolo Valente | 20bd723 | 2016-07-27 07:22:05 +0200 | [diff] [blame] | 633 | |
Dennis Zhou | db6638d | 2018-12-05 12:10:35 -0500 | [diff] [blame] | 634 | bio_clone_blkg_association(bio, bio_src); |
Dennis Zhou | e439bed | 2018-12-05 12:10:32 -0500 | [diff] [blame] | 635 | blkcg_bio_issue_init(bio); |
Kent Overstreet | 59d276f | 2013-11-23 18:19:27 -0800 | [diff] [blame] | 636 | } |
| 637 | EXPORT_SYMBOL(__bio_clone_fast); |
| 638 | |
| 639 | /** |
| 640 | * bio_clone_fast - clone a bio that shares the original bio's biovec |
| 641 | * @bio: bio to clone |
| 642 | * @gfp_mask: allocation priority |
| 643 | * @bs: bio_set to allocate from |
| 644 | * |
| 645 | * Like __bio_clone_fast, only also allocates the returned bio |
| 646 | */ |
| 647 | struct bio *bio_clone_fast(struct bio *bio, gfp_t gfp_mask, struct bio_set *bs) |
| 648 | { |
| 649 | struct bio *b; |
| 650 | |
| 651 | b = bio_alloc_bioset(gfp_mask, 0, bs); |
| 652 | if (!b) |
| 653 | return NULL; |
| 654 | |
| 655 | __bio_clone_fast(b, bio); |
| 656 | |
| 657 | if (bio_integrity(bio)) { |
| 658 | int ret; |
| 659 | |
| 660 | ret = bio_integrity_clone(b, bio, gfp_mask); |
| 661 | |
| 662 | if (ret < 0) { |
| 663 | bio_put(b); |
| 664 | return NULL; |
| 665 | } |
| 666 | } |
| 667 | |
| 668 | return b; |
| 669 | } |
| 670 | EXPORT_SYMBOL(bio_clone_fast); |
| 671 | |
Ming Lei | 5919482 | 2019-03-17 18:01:07 +0800 | [diff] [blame] | 672 | static inline bool page_is_mergeable(const struct bio_vec *bv, |
| 673 | struct page *page, unsigned int len, unsigned int off, |
Christoph Hellwig | ff89673 | 2019-06-17 11:14:11 +0200 | [diff] [blame] | 674 | bool *same_page) |
Ming Lei | 5919482 | 2019-03-17 18:01:07 +0800 | [diff] [blame] | 675 | { |
| 676 | phys_addr_t vec_end_addr = page_to_phys(bv->bv_page) + |
| 677 | bv->bv_offset + bv->bv_len - 1; |
| 678 | phys_addr_t page_addr = page_to_phys(page); |
| 679 | |
| 680 | if (vec_end_addr + 1 != page_addr + off) |
| 681 | return false; |
| 682 | if (xen_domain() && !xen_biovec_phys_mergeable(bv, page)) |
| 683 | return false; |
Christoph Hellwig | 52d52d1 | 2019-04-11 08:23:31 +0200 | [diff] [blame] | 684 | |
Christoph Hellwig | ff89673 | 2019-06-17 11:14:11 +0200 | [diff] [blame] | 685 | *same_page = ((vec_end_addr & PAGE_MASK) == page_addr); |
| 686 | if (!*same_page && pfn_to_page(PFN_DOWN(vec_end_addr)) + 1 != page) |
| 687 | return false; |
Ming Lei | 5919482 | 2019-03-17 18:01:07 +0800 | [diff] [blame] | 688 | return true; |
| 689 | } |
| 690 | |
Christoph Hellwig | 384209c | 2019-08-12 17:39:57 +0200 | [diff] [blame] | 691 | static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio, |
| 692 | struct page *page, unsigned len, unsigned offset, |
| 693 | bool *same_page) |
Ming Lei | 489fbbc | 2019-03-29 15:08:00 +0800 | [diff] [blame] | 694 | { |
Christoph Hellwig | 384209c | 2019-08-12 17:39:57 +0200 | [diff] [blame] | 695 | struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; |
Ming Lei | 489fbbc | 2019-03-29 15:08:00 +0800 | [diff] [blame] | 696 | unsigned long mask = queue_segment_boundary(q); |
| 697 | phys_addr_t addr1 = page_to_phys(bv->bv_page) + bv->bv_offset; |
| 698 | phys_addr_t addr2 = page_to_phys(page) + offset + len - 1; |
| 699 | |
| 700 | if ((addr1 | mask) != (addr2 | mask)) |
| 701 | return false; |
Ming Lei | 489fbbc | 2019-03-29 15:08:00 +0800 | [diff] [blame] | 702 | if (bv->bv_len + len > queue_max_segment_size(q)) |
| 703 | return false; |
Christoph Hellwig | 384209c | 2019-08-12 17:39:57 +0200 | [diff] [blame] | 704 | return __bio_try_merge_page(bio, page, len, offset, same_page); |
Ming Lei | 489fbbc | 2019-03-29 15:08:00 +0800 | [diff] [blame] | 705 | } |
| 706 | |
Shaohua Li | f459587 | 2017-03-24 10:34:43 -0700 | [diff] [blame] | 707 | /** |
Ming Lei | 1904708 | 2019-03-17 18:01:08 +0800 | [diff] [blame] | 708 | * __bio_add_pc_page - attempt to add page to passthrough bio |
Kent Overstreet | c66a14d | 2013-11-23 22:30:22 -0800 | [diff] [blame] | 709 | * @q: the target queue |
| 710 | * @bio: destination bio |
| 711 | * @page: page to add |
| 712 | * @len: vec entry length |
| 713 | * @offset: vec entry offset |
Christoph Hellwig | d1916c8 | 2019-08-12 17:39:58 +0200 | [diff] [blame] | 714 | * @same_page: return if the merge happen inside the same page |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 715 | * |
Kent Overstreet | c66a14d | 2013-11-23 22:30:22 -0800 | [diff] [blame] | 716 | * Attempt to add a page to the bio_vec maplist. This can fail for a |
| 717 | * number of reasons, such as the bio being full or target block device |
| 718 | * limitations. The target block device must allow bio's up to PAGE_SIZE, |
| 719 | * so it is always possible to add a single page to an empty bio. |
| 720 | * |
Ming Lei | 5a8ce24 | 2019-03-17 18:01:06 +0800 | [diff] [blame] | 721 | * This should only be used by passthrough bios. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 722 | */ |
Christoph Hellwig | 4713839 | 2019-04-25 09:04:33 +0200 | [diff] [blame] | 723 | static int __bio_add_pc_page(struct request_queue *q, struct bio *bio, |
Ming Lei | 1904708 | 2019-03-17 18:01:08 +0800 | [diff] [blame] | 724 | struct page *page, unsigned int len, unsigned int offset, |
Christoph Hellwig | d1916c8 | 2019-08-12 17:39:58 +0200 | [diff] [blame] | 725 | bool *same_page) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 726 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | struct bio_vec *bvec; |
| 728 | |
| 729 | /* |
| 730 | * cloned bio must not modify vec list |
| 731 | */ |
| 732 | if (unlikely(bio_flagged(bio, BIO_CLONED))) |
| 733 | return 0; |
| 734 | |
Kent Overstreet | c66a14d | 2013-11-23 22:30:22 -0800 | [diff] [blame] | 735 | if (((bio->bi_iter.bi_size + len) >> 9) > queue_max_hw_sectors(q)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 736 | return 0; |
| 737 | |
Jens Axboe | 80cfd54 | 2006-01-06 09:43:28 +0100 | [diff] [blame] | 738 | if (bio->bi_vcnt > 0) { |
Christoph Hellwig | d1916c8 | 2019-08-12 17:39:58 +0200 | [diff] [blame] | 739 | if (bio_try_merge_pc_page(q, bio, page, len, offset, same_page)) |
Christoph Hellwig | 384209c | 2019-08-12 17:39:57 +0200 | [diff] [blame] | 740 | return len; |
Christoph Hellwig | 320ea86 | 2019-08-12 17:39:56 +0200 | [diff] [blame] | 741 | |
| 742 | /* |
| 743 | * If the queue doesn't support SG gaps and adding this segment |
| 744 | * would create a gap, disallow it. |
| 745 | */ |
Christoph Hellwig | 384209c | 2019-08-12 17:39:57 +0200 | [diff] [blame] | 746 | bvec = &bio->bi_io_vec[bio->bi_vcnt - 1]; |
Christoph Hellwig | 320ea86 | 2019-08-12 17:39:56 +0200 | [diff] [blame] | 747 | if (bvec_gap_to_prev(q, bvec, offset)) |
| 748 | return 0; |
Jens Axboe | 80cfd54 | 2006-01-06 09:43:28 +0100 | [diff] [blame] | 749 | } |
| 750 | |
Ming Lei | 79d08f8 | 2019-07-01 15:14:46 +0800 | [diff] [blame] | 751 | if (bio_full(bio, len)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 752 | return 0; |
| 753 | |
Christoph Hellwig | 14ccb66 | 2019-06-06 12:29:01 +0200 | [diff] [blame] | 754 | if (bio->bi_vcnt >= queue_max_segments(q)) |
Ming Lei | 489fbbc | 2019-03-29 15:08:00 +0800 | [diff] [blame] | 755 | return 0; |
| 756 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 757 | bvec = &bio->bi_io_vec[bio->bi_vcnt]; |
| 758 | bvec->bv_page = page; |
| 759 | bvec->bv_len = len; |
| 760 | bvec->bv_offset = offset; |
Maurizio Lombardi | fcbf6a0 | 2014-12-10 14:16:53 -0800 | [diff] [blame] | 761 | bio->bi_vcnt++; |
Christoph Hellwig | dcdca75 | 2019-04-25 09:04:35 +0200 | [diff] [blame] | 762 | bio->bi_iter.bi_size += len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | return len; |
| 764 | } |
Ming Lei | 1904708 | 2019-03-17 18:01:08 +0800 | [diff] [blame] | 765 | |
| 766 | int bio_add_pc_page(struct request_queue *q, struct bio *bio, |
| 767 | struct page *page, unsigned int len, unsigned int offset) |
| 768 | { |
Christoph Hellwig | d1916c8 | 2019-08-12 17:39:58 +0200 | [diff] [blame] | 769 | bool same_page = false; |
| 770 | return __bio_add_pc_page(q, bio, page, len, offset, &same_page); |
Ming Lei | 1904708 | 2019-03-17 18:01:08 +0800 | [diff] [blame] | 771 | } |
H Hartley Sweeten | a112a71 | 2009-09-26 16:19:21 +0200 | [diff] [blame] | 772 | EXPORT_SYMBOL(bio_add_pc_page); |
Mike Christie | 6e68af6 | 2005-11-11 05:30:27 -0600 | [diff] [blame] | 773 | |
| 774 | /** |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 775 | * __bio_try_merge_page - try appending data to an existing bvec. |
| 776 | * @bio: destination bio |
Ming Lei | 551879a | 2019-04-23 10:51:04 +0800 | [diff] [blame] | 777 | * @page: start page to add |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 778 | * @len: length of the data to add |
Ming Lei | 551879a | 2019-04-23 10:51:04 +0800 | [diff] [blame] | 779 | * @off: offset of the data relative to @page |
Christoph Hellwig | ff89673 | 2019-06-17 11:14:11 +0200 | [diff] [blame] | 780 | * @same_page: return if the segment has been merged inside the same page |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 781 | * |
| 782 | * Try to add the data at @page + @off to the last bvec of @bio. This is a |
| 783 | * a useful optimisation for file systems with a block size smaller than the |
| 784 | * page size. |
| 785 | * |
Ming Lei | 551879a | 2019-04-23 10:51:04 +0800 | [diff] [blame] | 786 | * Warn if (@len, @off) crosses pages in case that @same_page is true. |
| 787 | * |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 788 | * Return %true on success or %false on failure. |
| 789 | */ |
| 790 | bool __bio_try_merge_page(struct bio *bio, struct page *page, |
Christoph Hellwig | ff89673 | 2019-06-17 11:14:11 +0200 | [diff] [blame] | 791 | unsigned int len, unsigned int off, bool *same_page) |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 792 | { |
| 793 | if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) |
| 794 | return false; |
| 795 | |
Andreas Gruenbacher | cc90bc6 | 2019-12-09 20:11:14 +0100 | [diff] [blame] | 796 | if (bio->bi_vcnt > 0) { |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 797 | struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; |
| 798 | |
Ming Lei | 5919482 | 2019-03-17 18:01:07 +0800 | [diff] [blame] | 799 | if (page_is_mergeable(bv, page, len, off, same_page)) { |
Andreas Gruenbacher | cc90bc6 | 2019-12-09 20:11:14 +0100 | [diff] [blame] | 800 | if (bio->bi_iter.bi_size > UINT_MAX - len) |
| 801 | return false; |
Ming Lei | 5919482 | 2019-03-17 18:01:07 +0800 | [diff] [blame] | 802 | bv->bv_len += len; |
| 803 | bio->bi_iter.bi_size += len; |
| 804 | return true; |
| 805 | } |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 806 | } |
| 807 | return false; |
| 808 | } |
| 809 | EXPORT_SYMBOL_GPL(__bio_try_merge_page); |
| 810 | |
| 811 | /** |
Ming Lei | 551879a | 2019-04-23 10:51:04 +0800 | [diff] [blame] | 812 | * __bio_add_page - add page(s) to a bio in a new segment |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 813 | * @bio: destination bio |
Ming Lei | 551879a | 2019-04-23 10:51:04 +0800 | [diff] [blame] | 814 | * @page: start page to add |
| 815 | * @len: length of the data to add, may cross pages |
| 816 | * @off: offset of the data relative to @page, may cross pages |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 817 | * |
| 818 | * Add the data at @page + @off to @bio as a new bvec. The caller must ensure |
| 819 | * that @bio has space for another bvec. |
| 820 | */ |
| 821 | void __bio_add_page(struct bio *bio, struct page *page, |
| 822 | unsigned int len, unsigned int off) |
| 823 | { |
| 824 | struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt]; |
| 825 | |
| 826 | WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); |
Ming Lei | 79d08f8 | 2019-07-01 15:14:46 +0800 | [diff] [blame] | 827 | WARN_ON_ONCE(bio_full(bio, len)); |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 828 | |
| 829 | bv->bv_page = page; |
| 830 | bv->bv_offset = off; |
| 831 | bv->bv_len = len; |
| 832 | |
| 833 | bio->bi_iter.bi_size += len; |
| 834 | bio->bi_vcnt++; |
Johannes Weiner | b8e24a9 | 2019-08-08 15:03:00 -0400 | [diff] [blame] | 835 | |
| 836 | if (!bio_flagged(bio, BIO_WORKINGSET) && unlikely(PageWorkingset(page))) |
| 837 | bio_set_flag(bio, BIO_WORKINGSET); |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 838 | } |
| 839 | EXPORT_SYMBOL_GPL(__bio_add_page); |
| 840 | |
| 841 | /** |
Ming Lei | 551879a | 2019-04-23 10:51:04 +0800 | [diff] [blame] | 842 | * bio_add_page - attempt to add page(s) to bio |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 843 | * @bio: destination bio |
Ming Lei | 551879a | 2019-04-23 10:51:04 +0800 | [diff] [blame] | 844 | * @page: start page to add |
| 845 | * @len: vec entry length, may cross pages |
| 846 | * @offset: vec entry offset relative to @page, may cross pages |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 847 | * |
Ming Lei | 551879a | 2019-04-23 10:51:04 +0800 | [diff] [blame] | 848 | * Attempt to add page(s) to the bio_vec maplist. This will only fail |
Kent Overstreet | c66a14d | 2013-11-23 22:30:22 -0800 | [diff] [blame] | 849 | * if either bio->bi_vcnt == bio->bi_max_vecs or it's a cloned bio. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 850 | */ |
Kent Overstreet | c66a14d | 2013-11-23 22:30:22 -0800 | [diff] [blame] | 851 | int bio_add_page(struct bio *bio, struct page *page, |
| 852 | unsigned int len, unsigned int offset) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | { |
Christoph Hellwig | ff89673 | 2019-06-17 11:14:11 +0200 | [diff] [blame] | 854 | bool same_page = false; |
| 855 | |
| 856 | if (!__bio_try_merge_page(bio, page, len, offset, &same_page)) { |
Ming Lei | 79d08f8 | 2019-07-01 15:14:46 +0800 | [diff] [blame] | 857 | if (bio_full(bio, len)) |
Christoph Hellwig | 0aa69fd | 2018-06-01 09:03:05 -0700 | [diff] [blame] | 858 | return 0; |
| 859 | __bio_add_page(bio, page, len, offset); |
Kent Overstreet | c66a14d | 2013-11-23 22:30:22 -0800 | [diff] [blame] | 860 | } |
Kent Overstreet | c66a14d | 2013-11-23 22:30:22 -0800 | [diff] [blame] | 861 | return len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 862 | } |
H Hartley Sweeten | a112a71 | 2009-09-26 16:19:21 +0200 | [diff] [blame] | 863 | EXPORT_SYMBOL(bio_add_page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 864 | |
Christoph Hellwig | d241a95 | 2019-06-26 15:49:21 +0200 | [diff] [blame] | 865 | void bio_release_pages(struct bio *bio, bool mark_dirty) |
Christoph Hellwig | 7321ecb | 2019-04-11 08:23:30 +0200 | [diff] [blame] | 866 | { |
| 867 | struct bvec_iter_all iter_all; |
| 868 | struct bio_vec *bvec; |
Christoph Hellwig | 7321ecb | 2019-04-11 08:23:30 +0200 | [diff] [blame] | 869 | |
Christoph Hellwig | b2d0d99 | 2019-06-26 15:49:20 +0200 | [diff] [blame] | 870 | if (bio_flagged(bio, BIO_NO_PAGE_REF)) |
| 871 | return; |
| 872 | |
Christoph Hellwig | d241a95 | 2019-06-26 15:49:21 +0200 | [diff] [blame] | 873 | bio_for_each_segment_all(bvec, bio, iter_all) { |
| 874 | if (mark_dirty && !PageCompound(bvec->bv_page)) |
| 875 | set_page_dirty_lock(bvec->bv_page); |
Christoph Hellwig | 7321ecb | 2019-04-11 08:23:30 +0200 | [diff] [blame] | 876 | put_page(bvec->bv_page); |
Christoph Hellwig | d241a95 | 2019-06-26 15:49:21 +0200 | [diff] [blame] | 877 | } |
Christoph Hellwig | 7321ecb | 2019-04-11 08:23:30 +0200 | [diff] [blame] | 878 | } |
| 879 | |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 880 | static int __bio_iov_bvec_add_pages(struct bio *bio, struct iov_iter *iter) |
| 881 | { |
| 882 | const struct bio_vec *bv = iter->bvec; |
| 883 | unsigned int len; |
| 884 | size_t size; |
| 885 | |
| 886 | if (WARN_ON_ONCE(iter->iov_offset > bv->bv_len)) |
| 887 | return -EINVAL; |
| 888 | |
| 889 | len = min_t(size_t, bv->bv_len - iter->iov_offset, iter->count); |
| 890 | size = bio_add_page(bio, bv->bv_page, len, |
| 891 | bv->bv_offset + iter->iov_offset); |
Christoph Hellwig | a10584c | 2019-04-11 08:23:28 +0200 | [diff] [blame] | 892 | if (unlikely(size != len)) |
| 893 | return -EINVAL; |
Christoph Hellwig | a10584c | 2019-04-11 08:23:28 +0200 | [diff] [blame] | 894 | iov_iter_advance(iter, size); |
| 895 | return 0; |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 896 | } |
| 897 | |
Christoph Hellwig | 576ed91 | 2018-09-20 08:28:21 +0200 | [diff] [blame] | 898 | #define PAGE_PTRS_PER_BVEC (sizeof(struct bio_vec) / sizeof(struct page *)) |
| 899 | |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 900 | /** |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 901 | * __bio_iov_iter_get_pages - pin user or kernel pages and add them to a bio |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 902 | * @bio: bio to add pages to |
| 903 | * @iter: iov iterator describing the region to be mapped |
| 904 | * |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 905 | * Pins pages from *iter and appends them to @bio's bvec array. The |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 906 | * pages will have to be released using put_page() when done. |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 907 | * For multi-segment *iter, this function only adds pages from the |
| 908 | * the next non-empty segment of the iov iterator. |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 909 | */ |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 910 | static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 911 | { |
Christoph Hellwig | 576ed91 | 2018-09-20 08:28:21 +0200 | [diff] [blame] | 912 | unsigned short nr_pages = bio->bi_max_vecs - bio->bi_vcnt; |
| 913 | unsigned short entries_left = bio->bi_max_vecs - bio->bi_vcnt; |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 914 | struct bio_vec *bv = bio->bi_io_vec + bio->bi_vcnt; |
| 915 | struct page **pages = (struct page **)bv; |
Christoph Hellwig | 4569180 | 2019-06-17 11:14:12 +0200 | [diff] [blame] | 916 | bool same_page = false; |
Christoph Hellwig | 576ed91 | 2018-09-20 08:28:21 +0200 | [diff] [blame] | 917 | ssize_t size, left; |
| 918 | unsigned len, i; |
Martin Wilck | b403ea2 | 2018-07-25 23:15:07 +0200 | [diff] [blame] | 919 | size_t offset; |
Christoph Hellwig | 576ed91 | 2018-09-20 08:28:21 +0200 | [diff] [blame] | 920 | |
| 921 | /* |
| 922 | * Move page array up in the allocated memory for the bio vecs as far as |
| 923 | * possible so that we can start filling biovecs from the beginning |
| 924 | * without overwriting the temporary page array. |
| 925 | */ |
| 926 | BUILD_BUG_ON(PAGE_PTRS_PER_BVEC < 2); |
| 927 | pages += entries_left * (PAGE_PTRS_PER_BVEC - 1); |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 928 | |
| 929 | size = iov_iter_get_pages(iter, pages, LONG_MAX, nr_pages, &offset); |
| 930 | if (unlikely(size <= 0)) |
| 931 | return size ? size : -EFAULT; |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 932 | |
Christoph Hellwig | 576ed91 | 2018-09-20 08:28:21 +0200 | [diff] [blame] | 933 | for (left = size, i = 0; left > 0; left -= len, i++) { |
| 934 | struct page *page = pages[i]; |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 935 | |
Christoph Hellwig | 576ed91 | 2018-09-20 08:28:21 +0200 | [diff] [blame] | 936 | len = min_t(size_t, PAGE_SIZE - offset, left); |
Christoph Hellwig | 4569180 | 2019-06-17 11:14:12 +0200 | [diff] [blame] | 937 | |
| 938 | if (__bio_try_merge_page(bio, page, len, offset, &same_page)) { |
| 939 | if (same_page) |
| 940 | put_page(page); |
| 941 | } else { |
Ming Lei | 79d08f8 | 2019-07-01 15:14:46 +0800 | [diff] [blame] | 942 | if (WARN_ON_ONCE(bio_full(bio, len))) |
Christoph Hellwig | 4569180 | 2019-06-17 11:14:12 +0200 | [diff] [blame] | 943 | return -EINVAL; |
| 944 | __bio_add_page(bio, page, len, offset); |
| 945 | } |
Christoph Hellwig | 576ed91 | 2018-09-20 08:28:21 +0200 | [diff] [blame] | 946 | offset = 0; |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 947 | } |
| 948 | |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 949 | iov_iter_advance(iter, size); |
| 950 | return 0; |
| 951 | } |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 952 | |
| 953 | /** |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 954 | * bio_iov_iter_get_pages - add user or kernel pages to a bio |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 955 | * @bio: bio to add pages to |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 956 | * @iter: iov iterator describing the region to be added |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 957 | * |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 958 | * This takes either an iterator pointing to user memory, or one pointing to |
| 959 | * kernel pages (BVEC iterator). If we're adding user pages, we pin them and |
| 960 | * map them into the kernel. On IO completion, the caller should put those |
Jens Axboe | 399254a | 2019-02-27 13:13:23 -0700 | [diff] [blame] | 961 | * pages. If we're adding kernel pages, and the caller told us it's safe to |
| 962 | * do so, we just have to add the pages to the bio directly. We don't grab an |
| 963 | * extra reference to those pages (the user should already have that), and we |
| 964 | * don't put the page on IO completion. The caller needs to check if the bio is |
| 965 | * flagged BIO_NO_PAGE_REF on IO completion. If it isn't, then pages should be |
| 966 | * released. |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 967 | * |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 968 | * The function tries, but does not guarantee, to pin as many pages as |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 969 | * fit into the bio, or are requested in *iter, whatever is smaller. If |
| 970 | * MM encounters an error pinning the requested pages, it stops. Error |
| 971 | * is returned only if 0 pages could be pinned. |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 972 | */ |
| 973 | int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) |
| 974 | { |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 975 | const bool is_bvec = iov_iter_is_bvec(iter); |
Christoph Hellwig | 14eacf1 | 2019-04-11 08:23:29 +0200 | [diff] [blame] | 976 | int ret; |
| 977 | |
| 978 | if (WARN_ON_ONCE(bio->bi_vcnt)) |
| 979 | return -EINVAL; |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 980 | |
| 981 | do { |
Jens Axboe | 6d0c48a | 2018-11-30 08:47:03 -0700 | [diff] [blame] | 982 | if (is_bvec) |
| 983 | ret = __bio_iov_bvec_add_pages(bio, iter); |
| 984 | else |
| 985 | ret = __bio_iov_iter_get_pages(bio, iter); |
Ming Lei | 79d08f8 | 2019-07-01 15:14:46 +0800 | [diff] [blame] | 986 | } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0)); |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 987 | |
Christoph Hellwig | b620743 | 2019-06-26 15:49:28 +0200 | [diff] [blame] | 988 | if (is_bvec) |
Christoph Hellwig | 7321ecb | 2019-04-11 08:23:30 +0200 | [diff] [blame] | 989 | bio_set_flag(bio, BIO_NO_PAGE_REF); |
Christoph Hellwig | 14eacf1 | 2019-04-11 08:23:29 +0200 | [diff] [blame] | 990 | return bio->bi_vcnt ? 0 : ret; |
Martin Wilck | 17d51b1 | 2018-07-25 23:15:09 +0200 | [diff] [blame] | 991 | } |
Kent Overstreet | 2cefe4d | 2016-10-31 11:59:24 -0600 | [diff] [blame] | 992 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 993 | static void submit_bio_wait_endio(struct bio *bio) |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 994 | { |
Christoph Hellwig | 65e53aa | 2017-10-25 17:55:57 +0900 | [diff] [blame] | 995 | complete(bio->bi_private); |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 996 | } |
| 997 | |
| 998 | /** |
| 999 | * submit_bio_wait - submit a bio, and wait until it completes |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 1000 | * @bio: The &struct bio which describes the I/O |
| 1001 | * |
| 1002 | * Simple wrapper around submit_bio(). Returns 0 on success, or the error from |
| 1003 | * bio_endio() on failure. |
Jan Kara | 3d289d6 | 2017-08-02 10:25:21 +0200 | [diff] [blame] | 1004 | * |
| 1005 | * WARNING: Unlike to how submit_bio() is usually used, this function does not |
| 1006 | * result in bio reference to be consumed. The caller must drop the reference |
| 1007 | * on his own. |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 1008 | */ |
Mike Christie | 4e49ea4 | 2016-06-05 14:31:41 -0500 | [diff] [blame] | 1009 | int submit_bio_wait(struct bio *bio) |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 1010 | { |
Byungchul Park | e319e1f | 2017-10-25 17:56:05 +0900 | [diff] [blame] | 1011 | DECLARE_COMPLETION_ONSTACK_MAP(done, bio->bi_disk->lockdep_map); |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 1012 | |
Christoph Hellwig | 65e53aa | 2017-10-25 17:55:57 +0900 | [diff] [blame] | 1013 | bio->bi_private = &done; |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 1014 | bio->bi_end_io = submit_bio_wait_endio; |
Jens Axboe | 1eff9d3 | 2016-08-05 15:35:16 -0600 | [diff] [blame] | 1015 | bio->bi_opf |= REQ_SYNC; |
Mike Christie | 4e49ea4 | 2016-06-05 14:31:41 -0500 | [diff] [blame] | 1016 | submit_bio(bio); |
Christoph Hellwig | 65e53aa | 2017-10-25 17:55:57 +0900 | [diff] [blame] | 1017 | wait_for_completion_io(&done); |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 1018 | |
Christoph Hellwig | 65e53aa | 2017-10-25 17:55:57 +0900 | [diff] [blame] | 1019 | return blk_status_to_errno(bio->bi_status); |
Kent Overstreet | 9e88224 | 2012-09-10 14:41:12 -0700 | [diff] [blame] | 1020 | } |
| 1021 | EXPORT_SYMBOL(submit_bio_wait); |
| 1022 | |
Kent Overstreet | 054bdf6 | 2012-09-28 13:17:55 -0700 | [diff] [blame] | 1023 | /** |
| 1024 | * bio_advance - increment/complete a bio by some number of bytes |
| 1025 | * @bio: bio to advance |
| 1026 | * @bytes: number of bytes to complete |
| 1027 | * |
| 1028 | * This updates bi_sector, bi_size and bi_idx; if the number of bytes to |
| 1029 | * complete doesn't align with a bvec boundary, then bv_len and bv_offset will |
| 1030 | * be updated on the last bvec as well. |
| 1031 | * |
| 1032 | * @bio will then represent the remaining, uncompleted portion of the io. |
| 1033 | */ |
| 1034 | void bio_advance(struct bio *bio, unsigned bytes) |
| 1035 | { |
| 1036 | if (bio_integrity(bio)) |
| 1037 | bio_integrity_advance(bio, bytes); |
| 1038 | |
Kent Overstreet | 4550dd6 | 2013-08-07 14:26:21 -0700 | [diff] [blame] | 1039 | bio_advance_iter(bio, &bio->bi_iter, bytes); |
Kent Overstreet | 054bdf6 | 2012-09-28 13:17:55 -0700 | [diff] [blame] | 1040 | } |
| 1041 | EXPORT_SYMBOL(bio_advance); |
| 1042 | |
Kent Overstreet | 45db54d | 2018-05-08 21:33:54 -0400 | [diff] [blame] | 1043 | void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, |
| 1044 | struct bio *src, struct bvec_iter *src_iter) |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1045 | { |
Kent Overstreet | 1cb9dda | 2013-08-07 14:26:39 -0700 | [diff] [blame] | 1046 | struct bio_vec src_bv, dst_bv; |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1047 | void *src_p, *dst_p; |
Kent Overstreet | 1cb9dda | 2013-08-07 14:26:39 -0700 | [diff] [blame] | 1048 | unsigned bytes; |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1049 | |
Kent Overstreet | 45db54d | 2018-05-08 21:33:54 -0400 | [diff] [blame] | 1050 | while (src_iter->bi_size && dst_iter->bi_size) { |
| 1051 | src_bv = bio_iter_iovec(src, *src_iter); |
| 1052 | dst_bv = bio_iter_iovec(dst, *dst_iter); |
| 1053 | |
| 1054 | bytes = min(src_bv.bv_len, dst_bv.bv_len); |
| 1055 | |
| 1056 | src_p = kmap_atomic(src_bv.bv_page); |
| 1057 | dst_p = kmap_atomic(dst_bv.bv_page); |
| 1058 | |
| 1059 | memcpy(dst_p + dst_bv.bv_offset, |
| 1060 | src_p + src_bv.bv_offset, |
| 1061 | bytes); |
| 1062 | |
| 1063 | kunmap_atomic(dst_p); |
| 1064 | kunmap_atomic(src_p); |
| 1065 | |
Kent Overstreet | 6e6e811 | 2018-05-08 21:33:55 -0400 | [diff] [blame] | 1066 | flush_dcache_page(dst_bv.bv_page); |
| 1067 | |
Kent Overstreet | 45db54d | 2018-05-08 21:33:54 -0400 | [diff] [blame] | 1068 | bio_advance_iter(src, src_iter, bytes); |
| 1069 | bio_advance_iter(dst, dst_iter, bytes); |
| 1070 | } |
| 1071 | } |
| 1072 | EXPORT_SYMBOL(bio_copy_data_iter); |
| 1073 | |
| 1074 | /** |
| 1075 | * bio_copy_data - copy contents of data buffers from one bio to another |
| 1076 | * @src: source bio |
| 1077 | * @dst: destination bio |
| 1078 | * |
| 1079 | * Stops when it reaches the end of either @src or @dst - that is, copies |
| 1080 | * min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of bios). |
| 1081 | */ |
| 1082 | void bio_copy_data(struct bio *dst, struct bio *src) |
| 1083 | { |
| 1084 | struct bvec_iter src_iter = src->bi_iter; |
| 1085 | struct bvec_iter dst_iter = dst->bi_iter; |
| 1086 | |
| 1087 | bio_copy_data_iter(dst, &dst_iter, src, &src_iter); |
| 1088 | } |
| 1089 | EXPORT_SYMBOL(bio_copy_data); |
| 1090 | |
| 1091 | /** |
| 1092 | * bio_list_copy_data - copy contents of data buffers from one chain of bios to |
| 1093 | * another |
| 1094 | * @src: source bio list |
| 1095 | * @dst: destination bio list |
| 1096 | * |
| 1097 | * Stops when it reaches the end of either the @src list or @dst list - that is, |
| 1098 | * copies min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of |
| 1099 | * bios). |
| 1100 | */ |
| 1101 | void bio_list_copy_data(struct bio *dst, struct bio *src) |
| 1102 | { |
| 1103 | struct bvec_iter src_iter = src->bi_iter; |
| 1104 | struct bvec_iter dst_iter = dst->bi_iter; |
| 1105 | |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1106 | while (1) { |
Kent Overstreet | 1cb9dda | 2013-08-07 14:26:39 -0700 | [diff] [blame] | 1107 | if (!src_iter.bi_size) { |
| 1108 | src = src->bi_next; |
| 1109 | if (!src) |
| 1110 | break; |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1111 | |
Kent Overstreet | 1cb9dda | 2013-08-07 14:26:39 -0700 | [diff] [blame] | 1112 | src_iter = src->bi_iter; |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1113 | } |
| 1114 | |
Kent Overstreet | 1cb9dda | 2013-08-07 14:26:39 -0700 | [diff] [blame] | 1115 | if (!dst_iter.bi_size) { |
| 1116 | dst = dst->bi_next; |
| 1117 | if (!dst) |
| 1118 | break; |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1119 | |
Kent Overstreet | 1cb9dda | 2013-08-07 14:26:39 -0700 | [diff] [blame] | 1120 | dst_iter = dst->bi_iter; |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1121 | } |
| 1122 | |
Kent Overstreet | 45db54d | 2018-05-08 21:33:54 -0400 | [diff] [blame] | 1123 | bio_copy_data_iter(dst, &dst_iter, src, &src_iter); |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1124 | } |
| 1125 | } |
Kent Overstreet | 45db54d | 2018-05-08 21:33:54 -0400 | [diff] [blame] | 1126 | EXPORT_SYMBOL(bio_list_copy_data); |
Kent Overstreet | 16ac3d6 | 2012-09-10 13:57:51 -0700 | [diff] [blame] | 1127 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | struct bio_map_data { |
FUJITA Tomonori | 152e283 | 2008-08-28 16:17:06 +0900 | [diff] [blame] | 1129 | int is_our_pages; |
Kent Overstreet | 26e49cf | 2015-01-18 16:16:31 +0100 | [diff] [blame] | 1130 | struct iov_iter iter; |
| 1131 | struct iovec iov[]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1132 | }; |
| 1133 | |
Al Viro | 0e5b935 | 2017-09-24 13:14:35 -0400 | [diff] [blame] | 1134 | static struct bio_map_data *bio_alloc_map_data(struct iov_iter *data, |
FUJITA Tomonori | 76029ff | 2008-08-25 20:36:08 +0200 | [diff] [blame] | 1135 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1136 | { |
Al Viro | 0e5b935 | 2017-09-24 13:14:35 -0400 | [diff] [blame] | 1137 | struct bio_map_data *bmd; |
| 1138 | if (data->nr_segs > UIO_MAXIOV) |
Jens Axboe | f3f63c1 | 2010-10-29 11:46:56 -0600 | [diff] [blame] | 1139 | return NULL; |
| 1140 | |
Gustavo A. R. Silva | f1f8f29 | 2019-06-10 10:04:12 -0500 | [diff] [blame] | 1141 | bmd = kmalloc(struct_size(bmd, iov, data->nr_segs), gfp_mask); |
Al Viro | 0e5b935 | 2017-09-24 13:14:35 -0400 | [diff] [blame] | 1142 | if (!bmd) |
| 1143 | return NULL; |
| 1144 | memcpy(bmd->iov, data->iov, sizeof(struct iovec) * data->nr_segs); |
| 1145 | bmd->iter = *data; |
| 1146 | bmd->iter.iov = bmd->iov; |
| 1147 | return bmd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1148 | } |
| 1149 | |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1150 | /** |
| 1151 | * bio_copy_from_iter - copy all pages from iov_iter to bio |
| 1152 | * @bio: The &struct bio which describes the I/O as destination |
| 1153 | * @iter: iov_iter as source |
| 1154 | * |
| 1155 | * Copy all pages from iov_iter to bio. |
| 1156 | * Returns 0 on success, or error on failure. |
| 1157 | */ |
Al Viro | 98a09d6 | 2017-09-24 12:14:36 -0400 | [diff] [blame] | 1158 | static int bio_copy_from_iter(struct bio *bio, struct iov_iter *iter) |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1159 | { |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1160 | struct bio_vec *bvec; |
Ming Lei | 6dc4f10 | 2019-02-15 19:13:19 +0800 | [diff] [blame] | 1161 | struct bvec_iter_all iter_all; |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1162 | |
Christoph Hellwig | 2b070cf | 2019-04-25 09:03:00 +0200 | [diff] [blame] | 1163 | bio_for_each_segment_all(bvec, bio, iter_all) { |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1164 | ssize_t ret; |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1165 | |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1166 | ret = copy_page_from_iter(bvec->bv_page, |
| 1167 | bvec->bv_offset, |
| 1168 | bvec->bv_len, |
Al Viro | 98a09d6 | 2017-09-24 12:14:36 -0400 | [diff] [blame] | 1169 | iter); |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1170 | |
Al Viro | 98a09d6 | 2017-09-24 12:14:36 -0400 | [diff] [blame] | 1171 | if (!iov_iter_count(iter)) |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1172 | break; |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1173 | |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1174 | if (ret < bvec->bv_len) |
| 1175 | return -EFAULT; |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1176 | } |
| 1177 | |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1178 | return 0; |
| 1179 | } |
| 1180 | |
| 1181 | /** |
| 1182 | * bio_copy_to_iter - copy all pages from bio to iov_iter |
| 1183 | * @bio: The &struct bio which describes the I/O as source |
| 1184 | * @iter: iov_iter as destination |
| 1185 | * |
| 1186 | * Copy all pages from bio to iov_iter. |
| 1187 | * Returns 0 on success, or error on failure. |
| 1188 | */ |
| 1189 | static int bio_copy_to_iter(struct bio *bio, struct iov_iter iter) |
| 1190 | { |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1191 | struct bio_vec *bvec; |
Ming Lei | 6dc4f10 | 2019-02-15 19:13:19 +0800 | [diff] [blame] | 1192 | struct bvec_iter_all iter_all; |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1193 | |
Christoph Hellwig | 2b070cf | 2019-04-25 09:03:00 +0200 | [diff] [blame] | 1194 | bio_for_each_segment_all(bvec, bio, iter_all) { |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1195 | ssize_t ret; |
| 1196 | |
| 1197 | ret = copy_page_to_iter(bvec->bv_page, |
| 1198 | bvec->bv_offset, |
| 1199 | bvec->bv_len, |
| 1200 | &iter); |
| 1201 | |
| 1202 | if (!iov_iter_count(&iter)) |
| 1203 | break; |
| 1204 | |
| 1205 | if (ret < bvec->bv_len) |
| 1206 | return -EFAULT; |
| 1207 | } |
| 1208 | |
| 1209 | return 0; |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1210 | } |
| 1211 | |
Guoqing Jiang | 491221f | 2016-09-22 03:10:01 -0400 | [diff] [blame] | 1212 | void bio_free_pages(struct bio *bio) |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1213 | { |
| 1214 | struct bio_vec *bvec; |
Ming Lei | 6dc4f10 | 2019-02-15 19:13:19 +0800 | [diff] [blame] | 1215 | struct bvec_iter_all iter_all; |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1216 | |
Christoph Hellwig | 2b070cf | 2019-04-25 09:03:00 +0200 | [diff] [blame] | 1217 | bio_for_each_segment_all(bvec, bio, iter_all) |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1218 | __free_page(bvec->bv_page); |
| 1219 | } |
Guoqing Jiang | 491221f | 2016-09-22 03:10:01 -0400 | [diff] [blame] | 1220 | EXPORT_SYMBOL(bio_free_pages); |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1221 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1222 | /** |
| 1223 | * bio_uncopy_user - finish previously mapped bio |
| 1224 | * @bio: bio being terminated |
| 1225 | * |
Christoph Hellwig | ddad8dd | 2015-01-18 16:16:29 +0100 | [diff] [blame] | 1226 | * Free pages allocated from bio_copy_user_iov() and write back data |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1227 | * to user space in case of a read. |
| 1228 | */ |
| 1229 | int bio_uncopy_user(struct bio *bio) |
| 1230 | { |
| 1231 | struct bio_map_data *bmd = bio->bi_private; |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1232 | int ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1233 | |
Roland Dreier | 35dc248 | 2013-08-05 17:55:01 -0700 | [diff] [blame] | 1234 | if (!bio_flagged(bio, BIO_NULL_MAPPED)) { |
| 1235 | /* |
| 1236 | * if we're in a workqueue, the request is orphaned, so |
Hannes Reinecke | 2d99b55 | 2016-02-12 09:39:15 +0100 | [diff] [blame] | 1237 | * don't copy into a random user address space, just free |
| 1238 | * and return -EINTR so user space doesn't expect any data. |
Roland Dreier | 35dc248 | 2013-08-05 17:55:01 -0700 | [diff] [blame] | 1239 | */ |
Hannes Reinecke | 2d99b55 | 2016-02-12 09:39:15 +0100 | [diff] [blame] | 1240 | if (!current->mm) |
| 1241 | ret = -EINTR; |
| 1242 | else if (bio_data_dir(bio) == READ) |
Dongsu Park | 9124d3f | 2015-01-18 16:16:34 +0100 | [diff] [blame] | 1243 | ret = bio_copy_to_iter(bio, bmd->iter); |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1244 | if (bmd->is_our_pages) |
| 1245 | bio_free_pages(bio); |
Roland Dreier | 35dc248 | 2013-08-05 17:55:01 -0700 | [diff] [blame] | 1246 | } |
Kent Overstreet | c8db444 | 2013-11-22 19:39:06 -0800 | [diff] [blame] | 1247 | kfree(bmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1248 | bio_put(bio); |
| 1249 | return ret; |
| 1250 | } |
| 1251 | |
| 1252 | /** |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1253 | * bio_copy_user_iov - copy user data to bio |
Kent Overstreet | 26e49cf | 2015-01-18 16:16:31 +0100 | [diff] [blame] | 1254 | * @q: destination block queue |
| 1255 | * @map_data: pointer to the rq_map_data holding pages (if necessary) |
| 1256 | * @iter: iovec iterator |
| 1257 | * @gfp_mask: memory allocation flags |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1258 | * |
| 1259 | * Prepares and returns a bio for indirect user io, bouncing data |
| 1260 | * to/from kernel pages as necessary. Must be paired with |
| 1261 | * call bio_uncopy_user() on io completion. |
| 1262 | */ |
FUJITA Tomonori | 152e283 | 2008-08-28 16:17:06 +0900 | [diff] [blame] | 1263 | struct bio *bio_copy_user_iov(struct request_queue *q, |
| 1264 | struct rq_map_data *map_data, |
Al Viro | e81cef5 | 2017-09-24 09:25:39 -0400 | [diff] [blame] | 1265 | struct iov_iter *iter, |
Kent Overstreet | 26e49cf | 2015-01-18 16:16:31 +0100 | [diff] [blame] | 1266 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1267 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1268 | struct bio_map_data *bmd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1269 | struct page *page; |
| 1270 | struct bio *bio; |
Al Viro | d16d44e | 2017-09-24 13:09:18 -0400 | [diff] [blame] | 1271 | int i = 0, ret; |
| 1272 | int nr_pages; |
Kent Overstreet | 26e49cf | 2015-01-18 16:16:31 +0100 | [diff] [blame] | 1273 | unsigned int len = iter->count; |
Geliang Tang | bd5cece | 2015-11-21 17:27:31 +0800 | [diff] [blame] | 1274 | unsigned int offset = map_data ? offset_in_page(map_data->offset) : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1275 | |
Al Viro | 0e5b935 | 2017-09-24 13:14:35 -0400 | [diff] [blame] | 1276 | bmd = bio_alloc_map_data(iter, gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1277 | if (!bmd) |
| 1278 | return ERR_PTR(-ENOMEM); |
| 1279 | |
Kent Overstreet | 26e49cf | 2015-01-18 16:16:31 +0100 | [diff] [blame] | 1280 | /* |
| 1281 | * We need to do a deep copy of the iov_iter including the iovecs. |
| 1282 | * The caller provided iov might point to an on-stack or otherwise |
| 1283 | * shortlived one. |
| 1284 | */ |
| 1285 | bmd->is_our_pages = map_data ? 0 : 1; |
Kent Overstreet | 26e49cf | 2015-01-18 16:16:31 +0100 | [diff] [blame] | 1286 | |
Al Viro | d16d44e | 2017-09-24 13:09:18 -0400 | [diff] [blame] | 1287 | nr_pages = DIV_ROUND_UP(offset + len, PAGE_SIZE); |
| 1288 | if (nr_pages > BIO_MAX_PAGES) |
| 1289 | nr_pages = BIO_MAX_PAGES; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1290 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1291 | ret = -ENOMEM; |
Tejun Heo | a9e9dc2 | 2009-04-15 22:10:27 +0900 | [diff] [blame] | 1292 | bio = bio_kmalloc(gfp_mask, nr_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1293 | if (!bio) |
| 1294 | goto out_bmd; |
| 1295 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1296 | ret = 0; |
FUJITA Tomonori | 56c451f | 2008-12-18 14:49:37 +0900 | [diff] [blame] | 1297 | |
| 1298 | if (map_data) { |
FUJITA Tomonori | e623ddb | 2008-12-18 14:49:36 +0900 | [diff] [blame] | 1299 | nr_pages = 1 << map_data->page_order; |
FUJITA Tomonori | 56c451f | 2008-12-18 14:49:37 +0900 | [diff] [blame] | 1300 | i = map_data->offset / PAGE_SIZE; |
| 1301 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1302 | while (len) { |
FUJITA Tomonori | e623ddb | 2008-12-18 14:49:36 +0900 | [diff] [blame] | 1303 | unsigned int bytes = PAGE_SIZE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1304 | |
FUJITA Tomonori | 56c451f | 2008-12-18 14:49:37 +0900 | [diff] [blame] | 1305 | bytes -= offset; |
| 1306 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1307 | if (bytes > len) |
| 1308 | bytes = len; |
| 1309 | |
FUJITA Tomonori | 152e283 | 2008-08-28 16:17:06 +0900 | [diff] [blame] | 1310 | if (map_data) { |
FUJITA Tomonori | e623ddb | 2008-12-18 14:49:36 +0900 | [diff] [blame] | 1311 | if (i == map_data->nr_entries * nr_pages) { |
FUJITA Tomonori | 152e283 | 2008-08-28 16:17:06 +0900 | [diff] [blame] | 1312 | ret = -ENOMEM; |
| 1313 | break; |
| 1314 | } |
FUJITA Tomonori | e623ddb | 2008-12-18 14:49:36 +0900 | [diff] [blame] | 1315 | |
| 1316 | page = map_data->pages[i / nr_pages]; |
| 1317 | page += (i % nr_pages); |
| 1318 | |
| 1319 | i++; |
| 1320 | } else { |
FUJITA Tomonori | 152e283 | 2008-08-28 16:17:06 +0900 | [diff] [blame] | 1321 | page = alloc_page(q->bounce_gfp | gfp_mask); |
FUJITA Tomonori | e623ddb | 2008-12-18 14:49:36 +0900 | [diff] [blame] | 1322 | if (!page) { |
| 1323 | ret = -ENOMEM; |
| 1324 | break; |
| 1325 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1326 | } |
| 1327 | |
Jérôme Glisse | a3761c3 | 2019-04-10 16:27:51 -0400 | [diff] [blame] | 1328 | if (bio_add_pc_page(q, bio, page, bytes, offset) < bytes) { |
| 1329 | if (!map_data) |
| 1330 | __free_page(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1331 | break; |
Jérôme Glisse | a3761c3 | 2019-04-10 16:27:51 -0400 | [diff] [blame] | 1332 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1333 | |
| 1334 | len -= bytes; |
FUJITA Tomonori | 56c451f | 2008-12-18 14:49:37 +0900 | [diff] [blame] | 1335 | offset = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1336 | } |
| 1337 | |
| 1338 | if (ret) |
| 1339 | goto cleanup; |
| 1340 | |
Al Viro | 2884d0b | 2017-09-24 12:09:21 -0400 | [diff] [blame] | 1341 | if (map_data) |
| 1342 | map_data->offset += bio->bi_iter.bi_size; |
| 1343 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1344 | /* |
| 1345 | * success |
| 1346 | */ |
David Howells | 00e2370 | 2018-10-22 13:07:28 +0100 | [diff] [blame] | 1347 | if ((iov_iter_rw(iter) == WRITE && (!map_data || !map_data->null_mapped)) || |
FUJITA Tomonori | ecb554a | 2009-07-09 14:46:53 +0200 | [diff] [blame] | 1348 | (map_data && map_data->from_user)) { |
Al Viro | 98a09d6 | 2017-09-24 12:14:36 -0400 | [diff] [blame] | 1349 | ret = bio_copy_from_iter(bio, iter); |
FUJITA Tomonori | c5dec1c | 2008-04-11 12:56:49 +0200 | [diff] [blame] | 1350 | if (ret) |
| 1351 | goto cleanup; |
Al Viro | 98a09d6 | 2017-09-24 12:14:36 -0400 | [diff] [blame] | 1352 | } else { |
Keith Busch | f55adad | 2018-12-10 08:44:42 -0700 | [diff] [blame] | 1353 | if (bmd->is_our_pages) |
| 1354 | zero_fill_bio(bio); |
Al Viro | 98a09d6 | 2017-09-24 12:14:36 -0400 | [diff] [blame] | 1355 | iov_iter_advance(iter, bio->bi_iter.bi_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1356 | } |
| 1357 | |
Kent Overstreet | 26e49cf | 2015-01-18 16:16:31 +0100 | [diff] [blame] | 1358 | bio->bi_private = bmd; |
Al Viro | 2884d0b | 2017-09-24 12:09:21 -0400 | [diff] [blame] | 1359 | if (map_data && map_data->null_mapped) |
| 1360 | bio_set_flag(bio, BIO_NULL_MAPPED); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1361 | return bio; |
| 1362 | cleanup: |
FUJITA Tomonori | 152e283 | 2008-08-28 16:17:06 +0900 | [diff] [blame] | 1363 | if (!map_data) |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1364 | bio_free_pages(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1365 | bio_put(bio); |
| 1366 | out_bmd: |
Kent Overstreet | c8db444 | 2013-11-22 19:39:06 -0800 | [diff] [blame] | 1367 | kfree(bmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1368 | return ERR_PTR(ret); |
| 1369 | } |
| 1370 | |
Christoph Hellwig | 37f19e5 | 2015-01-18 16:16:33 +0100 | [diff] [blame] | 1371 | /** |
| 1372 | * bio_map_user_iov - map user iovec into bio |
| 1373 | * @q: the struct request_queue for the bio |
| 1374 | * @iter: iovec iterator |
| 1375 | * @gfp_mask: memory allocation flags |
| 1376 | * |
| 1377 | * Map the user space address into a bio suitable for io to a block |
| 1378 | * device. Returns an error pointer in case of error. |
| 1379 | */ |
| 1380 | struct bio *bio_map_user_iov(struct request_queue *q, |
Al Viro | e81cef5 | 2017-09-24 09:25:39 -0400 | [diff] [blame] | 1381 | struct iov_iter *iter, |
Christoph Hellwig | 37f19e5 | 2015-01-18 16:16:33 +0100 | [diff] [blame] | 1382 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1383 | { |
Kent Overstreet | 26e49cf | 2015-01-18 16:16:31 +0100 | [diff] [blame] | 1384 | int j; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1385 | struct bio *bio; |
Al Viro | 076098e | 2017-09-23 16:08:57 -0400 | [diff] [blame] | 1386 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1387 | |
Al Viro | b282cc7 | 2017-09-23 16:24:59 -0400 | [diff] [blame] | 1388 | if (!iov_iter_count(iter)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1389 | return ERR_PTR(-EINVAL); |
| 1390 | |
Al Viro | b282cc7 | 2017-09-23 16:24:59 -0400 | [diff] [blame] | 1391 | bio = bio_kmalloc(gfp_mask, iov_iter_npages(iter, BIO_MAX_PAGES)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1392 | if (!bio) |
| 1393 | return ERR_PTR(-ENOMEM); |
| 1394 | |
Al Viro | 0a0f151 | 2017-09-24 12:30:17 -0400 | [diff] [blame] | 1395 | while (iov_iter_count(iter)) { |
Al Viro | 629e42b | 2017-09-23 16:13:10 -0400 | [diff] [blame] | 1396 | struct page **pages; |
Al Viro | 076098e | 2017-09-23 16:08:57 -0400 | [diff] [blame] | 1397 | ssize_t bytes; |
| 1398 | size_t offs, added = 0; |
| 1399 | int npages; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1400 | |
Al Viro | 0a0f151 | 2017-09-24 12:30:17 -0400 | [diff] [blame] | 1401 | bytes = iov_iter_get_pages_alloc(iter, &pages, LONG_MAX, &offs); |
Al Viro | 076098e | 2017-09-23 16:08:57 -0400 | [diff] [blame] | 1402 | if (unlikely(bytes <= 0)) { |
| 1403 | ret = bytes ? bytes : -EFAULT; |
James Bottomley | f1970ba | 2005-06-20 14:06:52 +0200 | [diff] [blame] | 1404 | goto out_unmap; |
Jens Axboe | 9917215 | 2006-06-16 13:02:29 +0200 | [diff] [blame] | 1405 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1406 | |
Al Viro | 076098e | 2017-09-23 16:08:57 -0400 | [diff] [blame] | 1407 | npages = DIV_ROUND_UP(offs + bytes, PAGE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1408 | |
Al Viro | 98f0bc9 | 2017-09-23 16:23:18 -0400 | [diff] [blame] | 1409 | if (unlikely(offs & queue_dma_alignment(q))) { |
| 1410 | ret = -EINVAL; |
| 1411 | j = 0; |
| 1412 | } else { |
| 1413 | for (j = 0; j < npages; j++) { |
| 1414 | struct page *page = pages[j]; |
| 1415 | unsigned int n = PAGE_SIZE - offs; |
Christoph Hellwig | d1916c8 | 2019-08-12 17:39:58 +0200 | [diff] [blame] | 1416 | bool same_page = false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1417 | |
Al Viro | 98f0bc9 | 2017-09-23 16:23:18 -0400 | [diff] [blame] | 1418 | if (n > bytes) |
| 1419 | n = bytes; |
James Bottomley | f1970ba | 2005-06-20 14:06:52 +0200 | [diff] [blame] | 1420 | |
Ming Lei | 1904708 | 2019-03-17 18:01:08 +0800 | [diff] [blame] | 1421 | if (!__bio_add_pc_page(q, bio, page, n, offs, |
Christoph Hellwig | d1916c8 | 2019-08-12 17:39:58 +0200 | [diff] [blame] | 1422 | &same_page)) { |
| 1423 | if (same_page) |
| 1424 | put_page(page); |
Al Viro | 98f0bc9 | 2017-09-23 16:23:18 -0400 | [diff] [blame] | 1425 | break; |
Christoph Hellwig | d1916c8 | 2019-08-12 17:39:58 +0200 | [diff] [blame] | 1426 | } |
Vitaly Mayatskikh | 95d78c2 | 2017-09-22 01:18:39 -0400 | [diff] [blame] | 1427 | |
Al Viro | 98f0bc9 | 2017-09-23 16:23:18 -0400 | [diff] [blame] | 1428 | added += n; |
| 1429 | bytes -= n; |
| 1430 | offs = 0; |
| 1431 | } |
Al Viro | 0a0f151 | 2017-09-24 12:30:17 -0400 | [diff] [blame] | 1432 | iov_iter_advance(iter, added); |
James Bottomley | f1970ba | 2005-06-20 14:06:52 +0200 | [diff] [blame] | 1433 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1434 | /* |
James Bottomley | f1970ba | 2005-06-20 14:06:52 +0200 | [diff] [blame] | 1435 | * release the pages we didn't map into the bio, if any |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1436 | */ |
Al Viro | 629e42b | 2017-09-23 16:13:10 -0400 | [diff] [blame] | 1437 | while (j < npages) |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 1438 | put_page(pages[j++]); |
Al Viro | 629e42b | 2017-09-23 16:13:10 -0400 | [diff] [blame] | 1439 | kvfree(pages); |
Al Viro | e2e115d | 2017-09-23 16:16:06 -0400 | [diff] [blame] | 1440 | /* couldn't stuff something into bio? */ |
| 1441 | if (bytes) |
| 1442 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1443 | } |
| 1444 | |
Jens Axboe | b7c44ed | 2015-07-24 12:37:59 -0600 | [diff] [blame] | 1445 | bio_set_flag(bio, BIO_USER_MAPPED); |
Christoph Hellwig | 37f19e5 | 2015-01-18 16:16:33 +0100 | [diff] [blame] | 1446 | |
| 1447 | /* |
Bart Van Assche | 5fad1b6 | 2017-02-01 08:20:08 -0800 | [diff] [blame] | 1448 | * subtle -- if bio_map_user_iov() ended up bouncing a bio, |
Christoph Hellwig | 37f19e5 | 2015-01-18 16:16:33 +0100 | [diff] [blame] | 1449 | * it would normally disappear when its bi_end_io is run. |
| 1450 | * however, we need it for the unmap, so grab an extra |
| 1451 | * reference to it |
| 1452 | */ |
| 1453 | bio_get(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1454 | return bio; |
James Bottomley | f1970ba | 2005-06-20 14:06:52 +0200 | [diff] [blame] | 1455 | |
| 1456 | out_unmap: |
Christoph Hellwig | 506e079 | 2019-06-26 15:49:23 +0200 | [diff] [blame] | 1457 | bio_release_pages(bio, false); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1458 | bio_put(bio); |
| 1459 | return ERR_PTR(ret); |
| 1460 | } |
| 1461 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1462 | /** |
| 1463 | * bio_unmap_user - unmap a bio |
| 1464 | * @bio: the bio being unmapped |
| 1465 | * |
Bart Van Assche | 5fad1b6 | 2017-02-01 08:20:08 -0800 | [diff] [blame] | 1466 | * Unmap a bio previously mapped by bio_map_user_iov(). Must be called from |
| 1467 | * process context. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1468 | * |
| 1469 | * bio_unmap_user() may sleep. |
| 1470 | */ |
| 1471 | void bio_unmap_user(struct bio *bio) |
| 1472 | { |
Christoph Hellwig | 163cc2d | 2019-06-26 15:49:22 +0200 | [diff] [blame] | 1473 | bio_release_pages(bio, bio_data_dir(bio) == READ); |
| 1474 | bio_put(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1475 | bio_put(bio); |
| 1476 | } |
| 1477 | |
Damien Le Moal | b4c5875 | 2019-07-01 14:09:15 +0900 | [diff] [blame] | 1478 | static void bio_invalidate_vmalloc_pages(struct bio *bio) |
| 1479 | { |
| 1480 | #ifdef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE |
| 1481 | if (bio->bi_private && !op_is_write(bio_op(bio))) { |
| 1482 | unsigned long i, len = 0; |
| 1483 | |
| 1484 | for (i = 0; i < bio->bi_vcnt; i++) |
| 1485 | len += bio->bi_io_vec[i].bv_len; |
| 1486 | invalidate_kernel_vmap_range(bio->bi_private, len); |
| 1487 | } |
| 1488 | #endif |
| 1489 | } |
| 1490 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1491 | static void bio_map_kern_endio(struct bio *bio) |
Jens Axboe | b823825 | 2005-06-20 14:05:27 +0200 | [diff] [blame] | 1492 | { |
Damien Le Moal | b4c5875 | 2019-07-01 14:09:15 +0900 | [diff] [blame] | 1493 | bio_invalidate_vmalloc_pages(bio); |
Jens Axboe | b823825 | 2005-06-20 14:05:27 +0200 | [diff] [blame] | 1494 | bio_put(bio); |
Jens Axboe | b823825 | 2005-06-20 14:05:27 +0200 | [diff] [blame] | 1495 | } |
| 1496 | |
Christoph Hellwig | 75c72b8 | 2015-01-18 16:16:32 +0100 | [diff] [blame] | 1497 | /** |
| 1498 | * bio_map_kern - map kernel address into bio |
| 1499 | * @q: the struct request_queue for the bio |
| 1500 | * @data: pointer to buffer to map |
| 1501 | * @len: length in bytes |
| 1502 | * @gfp_mask: allocation flags for bio allocation |
| 1503 | * |
| 1504 | * Map the kernel address into a bio suitable for io to a block |
| 1505 | * device. Returns an error pointer in case of error. |
| 1506 | */ |
| 1507 | struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len, |
| 1508 | gfp_t gfp_mask) |
Mike Christie | df46b9a | 2005-06-20 14:04:44 +0200 | [diff] [blame] | 1509 | { |
| 1510 | unsigned long kaddr = (unsigned long)data; |
| 1511 | unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| 1512 | unsigned long start = kaddr >> PAGE_SHIFT; |
| 1513 | const int nr_pages = end - start; |
Damien Le Moal | b4c5875 | 2019-07-01 14:09:15 +0900 | [diff] [blame] | 1514 | bool is_vmalloc = is_vmalloc_addr(data); |
| 1515 | struct page *page; |
Mike Christie | df46b9a | 2005-06-20 14:04:44 +0200 | [diff] [blame] | 1516 | int offset, i; |
| 1517 | struct bio *bio; |
| 1518 | |
Tejun Heo | a9e9dc2 | 2009-04-15 22:10:27 +0900 | [diff] [blame] | 1519 | bio = bio_kmalloc(gfp_mask, nr_pages); |
Mike Christie | df46b9a | 2005-06-20 14:04:44 +0200 | [diff] [blame] | 1520 | if (!bio) |
| 1521 | return ERR_PTR(-ENOMEM); |
| 1522 | |
Damien Le Moal | b4c5875 | 2019-07-01 14:09:15 +0900 | [diff] [blame] | 1523 | if (is_vmalloc) { |
| 1524 | flush_kernel_vmap_range(data, len); |
| 1525 | bio->bi_private = data; |
| 1526 | } |
| 1527 | |
Mike Christie | df46b9a | 2005-06-20 14:04:44 +0200 | [diff] [blame] | 1528 | offset = offset_in_page(kaddr); |
| 1529 | for (i = 0; i < nr_pages; i++) { |
| 1530 | unsigned int bytes = PAGE_SIZE - offset; |
| 1531 | |
| 1532 | if (len <= 0) |
| 1533 | break; |
| 1534 | |
| 1535 | if (bytes > len) |
| 1536 | bytes = len; |
| 1537 | |
Damien Le Moal | b4c5875 | 2019-07-01 14:09:15 +0900 | [diff] [blame] | 1538 | if (!is_vmalloc) |
| 1539 | page = virt_to_page(data); |
| 1540 | else |
| 1541 | page = vmalloc_to_page(data); |
| 1542 | if (bio_add_pc_page(q, bio, page, bytes, |
Christoph Hellwig | 75c72b8 | 2015-01-18 16:16:32 +0100 | [diff] [blame] | 1543 | offset) < bytes) { |
| 1544 | /* we don't support partial mappings */ |
| 1545 | bio_put(bio); |
| 1546 | return ERR_PTR(-EINVAL); |
| 1547 | } |
Mike Christie | df46b9a | 2005-06-20 14:04:44 +0200 | [diff] [blame] | 1548 | |
| 1549 | data += bytes; |
| 1550 | len -= bytes; |
| 1551 | offset = 0; |
| 1552 | } |
| 1553 | |
Jens Axboe | b823825 | 2005-06-20 14:05:27 +0200 | [diff] [blame] | 1554 | bio->bi_end_io = bio_map_kern_endio; |
Mike Christie | df46b9a | 2005-06-20 14:04:44 +0200 | [diff] [blame] | 1555 | return bio; |
| 1556 | } |
Mike Christie | df46b9a | 2005-06-20 14:04:44 +0200 | [diff] [blame] | 1557 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1558 | static void bio_copy_kern_endio(struct bio *bio) |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1559 | { |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1560 | bio_free_pages(bio); |
| 1561 | bio_put(bio); |
| 1562 | } |
| 1563 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1564 | static void bio_copy_kern_endio_read(struct bio *bio) |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1565 | { |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1566 | char *p = bio->bi_private; |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1567 | struct bio_vec *bvec; |
Ming Lei | 6dc4f10 | 2019-02-15 19:13:19 +0800 | [diff] [blame] | 1568 | struct bvec_iter_all iter_all; |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1569 | |
Christoph Hellwig | 2b070cf | 2019-04-25 09:03:00 +0200 | [diff] [blame] | 1570 | bio_for_each_segment_all(bvec, bio, iter_all) { |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1571 | memcpy(p, page_address(bvec->bv_page), bvec->bv_len); |
Kent Overstreet | c8db444 | 2013-11-22 19:39:06 -0800 | [diff] [blame] | 1572 | p += bvec->bv_len; |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1573 | } |
| 1574 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1575 | bio_copy_kern_endio(bio); |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1576 | } |
| 1577 | |
| 1578 | /** |
| 1579 | * bio_copy_kern - copy kernel address into bio |
| 1580 | * @q: the struct request_queue for the bio |
| 1581 | * @data: pointer to buffer to copy |
| 1582 | * @len: length in bytes |
| 1583 | * @gfp_mask: allocation flags for bio and page allocation |
Randy Dunlap | ffee025 | 2008-04-30 09:08:54 +0200 | [diff] [blame] | 1584 | * @reading: data direction is READ |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1585 | * |
| 1586 | * copy the kernel address into a bio suitable for io to a block |
| 1587 | * device. Returns an error pointer in case of error. |
| 1588 | */ |
| 1589 | struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len, |
| 1590 | gfp_t gfp_mask, int reading) |
| 1591 | { |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1592 | unsigned long kaddr = (unsigned long)data; |
| 1593 | unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| 1594 | unsigned long start = kaddr >> PAGE_SHIFT; |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1595 | struct bio *bio; |
| 1596 | void *p = data; |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1597 | int nr_pages = 0; |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1598 | |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1599 | /* |
| 1600 | * Overflow, abort |
| 1601 | */ |
| 1602 | if (end < start) |
| 1603 | return ERR_PTR(-EINVAL); |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1604 | |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1605 | nr_pages = end - start; |
| 1606 | bio = bio_kmalloc(gfp_mask, nr_pages); |
| 1607 | if (!bio) |
| 1608 | return ERR_PTR(-ENOMEM); |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1609 | |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1610 | while (len) { |
| 1611 | struct page *page; |
| 1612 | unsigned int bytes = PAGE_SIZE; |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1613 | |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1614 | if (bytes > len) |
| 1615 | bytes = len; |
| 1616 | |
| 1617 | page = alloc_page(q->bounce_gfp | gfp_mask); |
| 1618 | if (!page) |
| 1619 | goto cleanup; |
| 1620 | |
| 1621 | if (!reading) |
| 1622 | memcpy(page_address(page), p, bytes); |
| 1623 | |
| 1624 | if (bio_add_pc_page(q, bio, page, bytes, 0) < bytes) |
| 1625 | break; |
| 1626 | |
| 1627 | len -= bytes; |
| 1628 | p += bytes; |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1629 | } |
| 1630 | |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1631 | if (reading) { |
| 1632 | bio->bi_end_io = bio_copy_kern_endio_read; |
| 1633 | bio->bi_private = data; |
| 1634 | } else { |
| 1635 | bio->bi_end_io = bio_copy_kern_endio; |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1636 | } |
FUJITA Tomonori | 76029ff | 2008-08-25 20:36:08 +0200 | [diff] [blame] | 1637 | |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1638 | return bio; |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1639 | |
| 1640 | cleanup: |
Christoph Hellwig | 1dfa0f6 | 2015-01-18 16:16:30 +0100 | [diff] [blame] | 1641 | bio_free_pages(bio); |
Christoph Hellwig | 42d2683 | 2015-01-18 16:16:28 +0100 | [diff] [blame] | 1642 | bio_put(bio); |
| 1643 | return ERR_PTR(-ENOMEM); |
FUJITA Tomonori | 68154e9 | 2008-04-25 12:47:50 +0200 | [diff] [blame] | 1644 | } |
| 1645 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1646 | /* |
| 1647 | * bio_set_pages_dirty() and bio_check_pages_dirty() are support functions |
| 1648 | * for performing direct-IO in BIOs. |
| 1649 | * |
| 1650 | * The problem is that we cannot run set_page_dirty() from interrupt context |
| 1651 | * because the required locks are not interrupt-safe. So what we can do is to |
| 1652 | * mark the pages dirty _before_ performing IO. And in interrupt context, |
| 1653 | * check that the pages are still dirty. If so, fine. If not, redirty them |
| 1654 | * in process context. |
| 1655 | * |
| 1656 | * We special-case compound pages here: normally this means reads into hugetlb |
| 1657 | * pages. The logic in here doesn't really work right for compound pages |
| 1658 | * because the VM does not uniformly chase down the head page in all cases. |
| 1659 | * But dirtiness of compound pages is pretty meaningless anyway: the VM doesn't |
| 1660 | * handle them at all. So we skip compound pages here at an early stage. |
| 1661 | * |
| 1662 | * Note that this code is very hard to test under normal circumstances because |
| 1663 | * direct-io pins the pages with get_user_pages(). This makes |
| 1664 | * is_page_cache_freeable return false, and the VM will not clean the pages. |
Artem Bityutskiy | 0d5c3eb | 2012-07-25 18:12:08 +0300 | [diff] [blame] | 1665 | * But other code (eg, flusher threads) could clean the pages if they are mapped |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1666 | * pagecache. |
| 1667 | * |
| 1668 | * Simply disabling the call to bio_set_pages_dirty() is a good way to test the |
| 1669 | * deferred bio dirtying paths. |
| 1670 | */ |
| 1671 | |
| 1672 | /* |
| 1673 | * bio_set_pages_dirty() will mark all the bio's pages as dirty. |
| 1674 | */ |
| 1675 | void bio_set_pages_dirty(struct bio *bio) |
| 1676 | { |
Kent Overstreet | cb34e05 | 2012-09-05 15:22:02 -0700 | [diff] [blame] | 1677 | struct bio_vec *bvec; |
Ming Lei | 6dc4f10 | 2019-02-15 19:13:19 +0800 | [diff] [blame] | 1678 | struct bvec_iter_all iter_all; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1679 | |
Christoph Hellwig | 2b070cf | 2019-04-25 09:03:00 +0200 | [diff] [blame] | 1680 | bio_for_each_segment_all(bvec, bio, iter_all) { |
Christoph Hellwig | 3bb5098 | 2018-07-24 14:04:13 +0200 | [diff] [blame] | 1681 | if (!PageCompound(bvec->bv_page)) |
| 1682 | set_page_dirty_lock(bvec->bv_page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1683 | } |
| 1684 | } |
| 1685 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1686 | /* |
| 1687 | * bio_check_pages_dirty() will check that all the BIO's pages are still dirty. |
| 1688 | * If they are, then fine. If, however, some pages are clean then they must |
| 1689 | * have been written out during the direct-IO read. So we take another ref on |
Christoph Hellwig | 24d5493 | 2018-07-24 14:04:12 +0200 | [diff] [blame] | 1690 | * the BIO and re-dirty the pages in process context. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1691 | * |
| 1692 | * It is expected that bio_check_pages_dirty() will wholly own the BIO from |
Kirill A. Shutemov | ea1754a | 2016-04-01 15:29:48 +0300 | [diff] [blame] | 1693 | * here on. It will run one put_page() against each page and will run one |
| 1694 | * bio_put() against the BIO. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1695 | */ |
| 1696 | |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 1697 | static void bio_dirty_fn(struct work_struct *work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1698 | |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 1699 | static DECLARE_WORK(bio_dirty_work, bio_dirty_fn); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1700 | static DEFINE_SPINLOCK(bio_dirty_lock); |
| 1701 | static struct bio *bio_dirty_list; |
| 1702 | |
| 1703 | /* |
| 1704 | * This runs in process context |
| 1705 | */ |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 1706 | static void bio_dirty_fn(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1707 | { |
Christoph Hellwig | 24d5493 | 2018-07-24 14:04:12 +0200 | [diff] [blame] | 1708 | struct bio *bio, *next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1709 | |
Christoph Hellwig | 24d5493 | 2018-07-24 14:04:12 +0200 | [diff] [blame] | 1710 | spin_lock_irq(&bio_dirty_lock); |
| 1711 | next = bio_dirty_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1712 | bio_dirty_list = NULL; |
Christoph Hellwig | 24d5493 | 2018-07-24 14:04:12 +0200 | [diff] [blame] | 1713 | spin_unlock_irq(&bio_dirty_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1714 | |
Christoph Hellwig | 24d5493 | 2018-07-24 14:04:12 +0200 | [diff] [blame] | 1715 | while ((bio = next) != NULL) { |
| 1716 | next = bio->bi_private; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1717 | |
Christoph Hellwig | d241a95 | 2019-06-26 15:49:21 +0200 | [diff] [blame] | 1718 | bio_release_pages(bio, true); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1719 | bio_put(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1720 | } |
| 1721 | } |
| 1722 | |
| 1723 | void bio_check_pages_dirty(struct bio *bio) |
| 1724 | { |
Kent Overstreet | cb34e05 | 2012-09-05 15:22:02 -0700 | [diff] [blame] | 1725 | struct bio_vec *bvec; |
Christoph Hellwig | 24d5493 | 2018-07-24 14:04:12 +0200 | [diff] [blame] | 1726 | unsigned long flags; |
Ming Lei | 6dc4f10 | 2019-02-15 19:13:19 +0800 | [diff] [blame] | 1727 | struct bvec_iter_all iter_all; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1728 | |
Christoph Hellwig | 2b070cf | 2019-04-25 09:03:00 +0200 | [diff] [blame] | 1729 | bio_for_each_segment_all(bvec, bio, iter_all) { |
Christoph Hellwig | 24d5493 | 2018-07-24 14:04:12 +0200 | [diff] [blame] | 1730 | if (!PageDirty(bvec->bv_page) && !PageCompound(bvec->bv_page)) |
| 1731 | goto defer; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1732 | } |
| 1733 | |
Christoph Hellwig | d241a95 | 2019-06-26 15:49:21 +0200 | [diff] [blame] | 1734 | bio_release_pages(bio, false); |
Christoph Hellwig | 24d5493 | 2018-07-24 14:04:12 +0200 | [diff] [blame] | 1735 | bio_put(bio); |
| 1736 | return; |
| 1737 | defer: |
| 1738 | spin_lock_irqsave(&bio_dirty_lock, flags); |
| 1739 | bio->bi_private = bio_dirty_list; |
| 1740 | bio_dirty_list = bio; |
| 1741 | spin_unlock_irqrestore(&bio_dirty_lock, flags); |
| 1742 | schedule_work(&bio_dirty_work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1743 | } |
| 1744 | |
Mikulas Patocka | 5b18b5a | 2018-12-06 11:41:19 -0500 | [diff] [blame] | 1745 | void update_io_ticks(struct hd_struct *part, unsigned long now) |
| 1746 | { |
| 1747 | unsigned long stamp; |
| 1748 | again: |
| 1749 | stamp = READ_ONCE(part->stamp); |
| 1750 | if (unlikely(stamp != now)) { |
| 1751 | if (likely(cmpxchg(&part->stamp, stamp, now) == stamp)) { |
| 1752 | __part_stat_add(part, io_ticks, 1); |
| 1753 | } |
| 1754 | } |
| 1755 | if (part->partno) { |
| 1756 | part = &part_to_disk(part)->part0; |
| 1757 | goto again; |
| 1758 | } |
| 1759 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1760 | |
Michael Callahan | ddcf35d | 2018-07-18 04:47:39 -0700 | [diff] [blame] | 1761 | void generic_start_io_acct(struct request_queue *q, int op, |
Jens Axboe | d62e26b | 2017-06-30 21:55:08 -0600 | [diff] [blame] | 1762 | unsigned long sectors, struct hd_struct *part) |
Gu Zheng | 394ffa5 | 2014-11-24 11:05:22 +0800 | [diff] [blame] | 1763 | { |
Michael Callahan | ddcf35d | 2018-07-18 04:47:39 -0700 | [diff] [blame] | 1764 | const int sgrp = op_stat_group(op); |
Gu Zheng | 394ffa5 | 2014-11-24 11:05:22 +0800 | [diff] [blame] | 1765 | |
Mike Snitzer | 112f158 | 2018-12-06 11:41:18 -0500 | [diff] [blame] | 1766 | part_stat_lock(); |
| 1767 | |
Mikulas Patocka | 5b18b5a | 2018-12-06 11:41:19 -0500 | [diff] [blame] | 1768 | update_io_ticks(part, jiffies); |
Mike Snitzer | 112f158 | 2018-12-06 11:41:18 -0500 | [diff] [blame] | 1769 | part_stat_inc(part, ios[sgrp]); |
| 1770 | part_stat_add(part, sectors[sgrp], sectors); |
Michael Callahan | ddcf35d | 2018-07-18 04:47:39 -0700 | [diff] [blame] | 1771 | part_inc_in_flight(q, part, op_is_write(op)); |
Gu Zheng | 394ffa5 | 2014-11-24 11:05:22 +0800 | [diff] [blame] | 1772 | |
| 1773 | part_stat_unlock(); |
| 1774 | } |
| 1775 | EXPORT_SYMBOL(generic_start_io_acct); |
| 1776 | |
Michael Callahan | ddcf35d | 2018-07-18 04:47:39 -0700 | [diff] [blame] | 1777 | void generic_end_io_acct(struct request_queue *q, int req_op, |
Jens Axboe | d62e26b | 2017-06-30 21:55:08 -0600 | [diff] [blame] | 1778 | struct hd_struct *part, unsigned long start_time) |
Gu Zheng | 394ffa5 | 2014-11-24 11:05:22 +0800 | [diff] [blame] | 1779 | { |
Mikulas Patocka | 5b18b5a | 2018-12-06 11:41:19 -0500 | [diff] [blame] | 1780 | unsigned long now = jiffies; |
| 1781 | unsigned long duration = now - start_time; |
Michael Callahan | ddcf35d | 2018-07-18 04:47:39 -0700 | [diff] [blame] | 1782 | const int sgrp = op_stat_group(req_op); |
Gu Zheng | 394ffa5 | 2014-11-24 11:05:22 +0800 | [diff] [blame] | 1783 | |
Mike Snitzer | 112f158 | 2018-12-06 11:41:18 -0500 | [diff] [blame] | 1784 | part_stat_lock(); |
| 1785 | |
Mikulas Patocka | 5b18b5a | 2018-12-06 11:41:19 -0500 | [diff] [blame] | 1786 | update_io_ticks(part, now); |
Mike Snitzer | 112f158 | 2018-12-06 11:41:18 -0500 | [diff] [blame] | 1787 | part_stat_add(part, nsecs[sgrp], jiffies_to_nsecs(duration)); |
Mikulas Patocka | 5b18b5a | 2018-12-06 11:41:19 -0500 | [diff] [blame] | 1788 | part_stat_add(part, time_in_queue, duration); |
Michael Callahan | ddcf35d | 2018-07-18 04:47:39 -0700 | [diff] [blame] | 1789 | part_dec_in_flight(q, part, op_is_write(req_op)); |
Gu Zheng | 394ffa5 | 2014-11-24 11:05:22 +0800 | [diff] [blame] | 1790 | |
| 1791 | part_stat_unlock(); |
| 1792 | } |
| 1793 | EXPORT_SYMBOL(generic_end_io_acct); |
| 1794 | |
Jens Axboe | c4cf526 | 2015-04-17 16:15:18 -0600 | [diff] [blame] | 1795 | static inline bool bio_remaining_done(struct bio *bio) |
| 1796 | { |
| 1797 | /* |
| 1798 | * If we're not chaining, then ->__bi_remaining is always 1 and |
| 1799 | * we always end io on the first invocation. |
| 1800 | */ |
| 1801 | if (!bio_flagged(bio, BIO_CHAIN)) |
| 1802 | return true; |
| 1803 | |
| 1804 | BUG_ON(atomic_read(&bio->__bi_remaining) <= 0); |
| 1805 | |
Mike Snitzer | 326e1db | 2015-05-22 09:14:03 -0400 | [diff] [blame] | 1806 | if (atomic_dec_and_test(&bio->__bi_remaining)) { |
Jens Axboe | b7c44ed | 2015-07-24 12:37:59 -0600 | [diff] [blame] | 1807 | bio_clear_flag(bio, BIO_CHAIN); |
Jens Axboe | c4cf526 | 2015-04-17 16:15:18 -0600 | [diff] [blame] | 1808 | return true; |
Mike Snitzer | 326e1db | 2015-05-22 09:14:03 -0400 | [diff] [blame] | 1809 | } |
Jens Axboe | c4cf526 | 2015-04-17 16:15:18 -0600 | [diff] [blame] | 1810 | |
| 1811 | return false; |
| 1812 | } |
| 1813 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1814 | /** |
| 1815 | * bio_endio - end I/O on a bio |
| 1816 | * @bio: bio |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1817 | * |
| 1818 | * Description: |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1819 | * bio_endio() will end I/O on the whole bio. bio_endio() is the preferred |
| 1820 | * way to end I/O on a bio. No one should call bi_end_io() directly on a |
| 1821 | * bio unless they own it and thus know that it has an end_io function. |
NeilBrown | fbbaf70 | 2017-04-07 09:40:52 -0600 | [diff] [blame] | 1822 | * |
| 1823 | * bio_endio() can be called several times on a bio that has been chained |
| 1824 | * using bio_chain(). The ->bi_end_io() function will only be called the |
| 1825 | * last time. At this point the BLK_TA_COMPLETE tracing event will be |
| 1826 | * generated if BIO_TRACE_COMPLETION is set. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1827 | **/ |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1828 | void bio_endio(struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1829 | { |
Christoph Hellwig | ba8c696 | 2016-03-11 17:34:52 +0100 | [diff] [blame] | 1830 | again: |
Christoph Hellwig | 2b88551 | 2016-03-11 17:34:53 +0100 | [diff] [blame] | 1831 | if (!bio_remaining_done(bio)) |
Christoph Hellwig | ba8c696 | 2016-03-11 17:34:52 +0100 | [diff] [blame] | 1832 | return; |
Christoph Hellwig | 7c20f11 | 2017-07-03 16:58:43 -0600 | [diff] [blame] | 1833 | if (!bio_integrity_endio(bio)) |
| 1834 | return; |
Kent Overstreet | 196d38bc | 2013-11-23 18:34:15 -0800 | [diff] [blame] | 1835 | |
Josef Bacik | 67b42d0 | 2018-07-03 11:15:00 -0400 | [diff] [blame] | 1836 | if (bio->bi_disk) |
| 1837 | rq_qos_done_bio(bio->bi_disk->queue, bio); |
| 1838 | |
Christoph Hellwig | ba8c696 | 2016-03-11 17:34:52 +0100 | [diff] [blame] | 1839 | /* |
| 1840 | * Need to have a real endio function for chained bios, otherwise |
| 1841 | * various corner cases will break (like stacking block devices that |
| 1842 | * save/restore bi_end_io) - however, we want to avoid unbounded |
| 1843 | * recursion and blowing the stack. Tail call optimization would |
| 1844 | * handle this, but compiling with frame pointers also disables |
| 1845 | * gcc's sibling call optimization. |
| 1846 | */ |
| 1847 | if (bio->bi_end_io == bio_chain_endio) { |
| 1848 | bio = __bio_chain_endio(bio); |
| 1849 | goto again; |
Kent Overstreet | 196d38bc | 2013-11-23 18:34:15 -0800 | [diff] [blame] | 1850 | } |
Christoph Hellwig | ba8c696 | 2016-03-11 17:34:52 +0100 | [diff] [blame] | 1851 | |
Christoph Hellwig | 74d4699 | 2017-08-23 19:10:32 +0200 | [diff] [blame] | 1852 | if (bio->bi_disk && bio_flagged(bio, BIO_TRACE_COMPLETION)) { |
| 1853 | trace_block_bio_complete(bio->bi_disk->queue, bio, |
Bart Van Assche | a462b95 | 2017-06-13 08:07:33 -0700 | [diff] [blame] | 1854 | blk_status_to_errno(bio->bi_status)); |
NeilBrown | fbbaf70 | 2017-04-07 09:40:52 -0600 | [diff] [blame] | 1855 | bio_clear_flag(bio, BIO_TRACE_COMPLETION); |
| 1856 | } |
| 1857 | |
Shaohua Li | 9e234ee | 2017-03-27 10:51:41 -0700 | [diff] [blame] | 1858 | blk_throtl_bio_endio(bio); |
Shaohua Li | b222dd2 | 2017-07-10 11:40:17 -0700 | [diff] [blame] | 1859 | /* release cgroup info */ |
| 1860 | bio_uninit(bio); |
Christoph Hellwig | ba8c696 | 2016-03-11 17:34:52 +0100 | [diff] [blame] | 1861 | if (bio->bi_end_io) |
| 1862 | bio->bi_end_io(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1863 | } |
H Hartley Sweeten | a112a71 | 2009-09-26 16:19:21 +0200 | [diff] [blame] | 1864 | EXPORT_SYMBOL(bio_endio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1865 | |
Kent Overstreet | 196d38bc | 2013-11-23 18:34:15 -0800 | [diff] [blame] | 1866 | /** |
Kent Overstreet | 20d0189 | 2013-11-23 18:21:01 -0800 | [diff] [blame] | 1867 | * bio_split - split a bio |
| 1868 | * @bio: bio to split |
| 1869 | * @sectors: number of sectors to split from the front of @bio |
| 1870 | * @gfp: gfp mask |
| 1871 | * @bs: bio set to allocate from |
| 1872 | * |
| 1873 | * Allocates and returns a new bio which represents @sectors from the start of |
| 1874 | * @bio, and updates @bio to represent the remaining sectors. |
| 1875 | * |
Martin K. Petersen | f3f5da6 | 2015-07-22 07:57:12 -0400 | [diff] [blame] | 1876 | * Unless this is a discard request the newly allocated bio will point |
Bart Van Assche | dad7758 | 2019-08-01 15:50:41 -0700 | [diff] [blame] | 1877 | * to @bio's bi_io_vec. It is the caller's responsibility to ensure that |
| 1878 | * neither @bio nor @bs are freed before the split bio. |
Kent Overstreet | 20d0189 | 2013-11-23 18:21:01 -0800 | [diff] [blame] | 1879 | */ |
| 1880 | struct bio *bio_split(struct bio *bio, int sectors, |
| 1881 | gfp_t gfp, struct bio_set *bs) |
| 1882 | { |
Mikulas Patocka | f341a4d | 2017-11-22 13:18:05 -0500 | [diff] [blame] | 1883 | struct bio *split; |
Kent Overstreet | 20d0189 | 2013-11-23 18:21:01 -0800 | [diff] [blame] | 1884 | |
| 1885 | BUG_ON(sectors <= 0); |
| 1886 | BUG_ON(sectors >= bio_sectors(bio)); |
| 1887 | |
Christoph Hellwig | f9d03f9 | 2016-12-08 15:20:32 -0700 | [diff] [blame] | 1888 | split = bio_clone_fast(bio, gfp, bs); |
Kent Overstreet | 20d0189 | 2013-11-23 18:21:01 -0800 | [diff] [blame] | 1889 | if (!split) |
| 1890 | return NULL; |
| 1891 | |
| 1892 | split->bi_iter.bi_size = sectors << 9; |
| 1893 | |
| 1894 | if (bio_integrity(split)) |
Dmitry Monakhov | fbd08e7 | 2017-06-29 11:31:10 -0700 | [diff] [blame] | 1895 | bio_integrity_trim(split); |
Kent Overstreet | 20d0189 | 2013-11-23 18:21:01 -0800 | [diff] [blame] | 1896 | |
| 1897 | bio_advance(bio, split->bi_iter.bi_size); |
| 1898 | |
NeilBrown | fbbaf70 | 2017-04-07 09:40:52 -0600 | [diff] [blame] | 1899 | if (bio_flagged(bio, BIO_TRACE_COMPLETION)) |
Goldwyn Rodrigues | 20d5902 | 2018-01-23 09:10:19 -0700 | [diff] [blame] | 1900 | bio_set_flag(split, BIO_TRACE_COMPLETION); |
NeilBrown | fbbaf70 | 2017-04-07 09:40:52 -0600 | [diff] [blame] | 1901 | |
Kent Overstreet | 20d0189 | 2013-11-23 18:21:01 -0800 | [diff] [blame] | 1902 | return split; |
| 1903 | } |
| 1904 | EXPORT_SYMBOL(bio_split); |
| 1905 | |
Martin K. Petersen | ad3316b | 2008-10-01 22:42:53 -0400 | [diff] [blame] | 1906 | /** |
Kent Overstreet | 6678d83 | 2013-08-07 11:14:32 -0700 | [diff] [blame] | 1907 | * bio_trim - trim a bio |
| 1908 | * @bio: bio to trim |
| 1909 | * @offset: number of sectors to trim from the front of @bio |
| 1910 | * @size: size we want to trim @bio to, in sectors |
| 1911 | */ |
| 1912 | void bio_trim(struct bio *bio, int offset, int size) |
| 1913 | { |
| 1914 | /* 'bio' is a cloned bio which we need to trim to match |
| 1915 | * the given offset and size. |
Kent Overstreet | 6678d83 | 2013-08-07 11:14:32 -0700 | [diff] [blame] | 1916 | */ |
Kent Overstreet | 6678d83 | 2013-08-07 11:14:32 -0700 | [diff] [blame] | 1917 | |
| 1918 | size <<= 9; |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1919 | if (offset == 0 && size == bio->bi_iter.bi_size) |
Kent Overstreet | 6678d83 | 2013-08-07 11:14:32 -0700 | [diff] [blame] | 1920 | return; |
| 1921 | |
Kent Overstreet | 6678d83 | 2013-08-07 11:14:32 -0700 | [diff] [blame] | 1922 | bio_advance(bio, offset << 9); |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1923 | bio->bi_iter.bi_size = size; |
Dmitry Monakhov | 376a78a | 2017-06-29 11:31:08 -0700 | [diff] [blame] | 1924 | |
| 1925 | if (bio_integrity(bio)) |
Dmitry Monakhov | fbd08e7 | 2017-06-29 11:31:10 -0700 | [diff] [blame] | 1926 | bio_integrity_trim(bio); |
Dmitry Monakhov | 376a78a | 2017-06-29 11:31:08 -0700 | [diff] [blame] | 1927 | |
Kent Overstreet | 6678d83 | 2013-08-07 11:14:32 -0700 | [diff] [blame] | 1928 | } |
| 1929 | EXPORT_SYMBOL_GPL(bio_trim); |
| 1930 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1931 | /* |
| 1932 | * create memory pools for biovec's in a bio_set. |
| 1933 | * use the global biovec slabs created for general use. |
| 1934 | */ |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 1935 | int biovec_init_pool(mempool_t *pool, int pool_entries) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1936 | { |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 1937 | struct biovec_slab *bp = bvec_slabs + BVEC_POOL_MAX; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1938 | |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 1939 | return mempool_init_slab_pool(pool, pool_entries, bp->slab); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1940 | } |
| 1941 | |
Kent Overstreet | 917a38c | 2018-05-08 21:33:51 -0400 | [diff] [blame] | 1942 | /* |
| 1943 | * bioset_exit - exit a bioset initialized with bioset_init() |
| 1944 | * |
| 1945 | * May be called on a zeroed but uninitialized bioset (i.e. allocated with |
| 1946 | * kzalloc()). |
| 1947 | */ |
| 1948 | void bioset_exit(struct bio_set *bs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1949 | { |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 1950 | if (bs->rescue_workqueue) |
| 1951 | destroy_workqueue(bs->rescue_workqueue); |
Kent Overstreet | 917a38c | 2018-05-08 21:33:51 -0400 | [diff] [blame] | 1952 | bs->rescue_workqueue = NULL; |
Kent Overstreet | df2cb6d | 2012-09-10 14:33:46 -0700 | [diff] [blame] | 1953 | |
Kent Overstreet | 8aa6ba2 | 2018-05-08 21:33:50 -0400 | [diff] [blame] | 1954 | mempool_exit(&bs->bio_pool); |
| 1955 | mempool_exit(&bs->bvec_pool); |
Kent Overstreet | 9f060e2 | 2012-10-12 15:29:33 -0700 | [diff] [blame] | 1956 | |
Martin K. Petersen | 7878cba | 2009-06-26 15:37:49 +0200 | [diff] [blame] | 1957 | bioset_integrity_free(bs); |
Kent Overstreet | 917a38c | 2018-05-08 21:33:51 -0400 | [diff] [blame] | 1958 | if (bs->bio_slab) |
| 1959 | bio_put_slab(bs); |
| 1960 | bs->bio_slab = NULL; |
| 1961 | } |
| 1962 | EXPORT_SYMBOL(bioset_exit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1963 | |
NeilBrown | 011067b | 2017-06-18 14:38:57 +1000 | [diff] [blame] | 1964 | /** |
Kent Overstreet | 917a38c | 2018-05-08 21:33:51 -0400 | [diff] [blame] | 1965 | * bioset_init - Initialize a bio_set |
Kent Overstreet | dad0852 | 2018-05-20 18:25:58 -0400 | [diff] [blame] | 1966 | * @bs: pool to initialize |
Kent Overstreet | 917a38c | 2018-05-08 21:33:51 -0400 | [diff] [blame] | 1967 | * @pool_size: Number of bio and bio_vecs to cache in the mempool |
| 1968 | * @front_pad: Number of bytes to allocate in front of the returned bio |
| 1969 | * @flags: Flags to modify behavior, currently %BIOSET_NEED_BVECS |
| 1970 | * and %BIOSET_NEED_RESCUER |
| 1971 | * |
Kent Overstreet | dad0852 | 2018-05-20 18:25:58 -0400 | [diff] [blame] | 1972 | * Description: |
| 1973 | * Set up a bio_set to be used with @bio_alloc_bioset. Allows the caller |
| 1974 | * to ask for a number of bytes to be allocated in front of the bio. |
| 1975 | * Front pad allocation is useful for embedding the bio inside |
| 1976 | * another structure, to avoid allocating extra data to go with the bio. |
| 1977 | * Note that the bio must be embedded at the END of that structure always, |
| 1978 | * or things will break badly. |
| 1979 | * If %BIOSET_NEED_BVECS is set in @flags, a separate pool will be allocated |
| 1980 | * for allocating iovecs. This pool is not needed e.g. for bio_clone_fast(). |
| 1981 | * If %BIOSET_NEED_RESCUER is set, a workqueue is created which can be used to |
| 1982 | * dispatch queued requests when the mempool runs out of space. |
| 1983 | * |
Kent Overstreet | 917a38c | 2018-05-08 21:33:51 -0400 | [diff] [blame] | 1984 | */ |
| 1985 | int bioset_init(struct bio_set *bs, |
| 1986 | unsigned int pool_size, |
| 1987 | unsigned int front_pad, |
| 1988 | int flags) |
| 1989 | { |
| 1990 | unsigned int back_pad = BIO_INLINE_VECS * sizeof(struct bio_vec); |
| 1991 | |
| 1992 | bs->front_pad = front_pad; |
| 1993 | |
| 1994 | spin_lock_init(&bs->rescue_lock); |
| 1995 | bio_list_init(&bs->rescue_list); |
| 1996 | INIT_WORK(&bs->rescue_work, bio_alloc_rescue); |
| 1997 | |
| 1998 | bs->bio_slab = bio_find_or_create_slab(front_pad + back_pad); |
| 1999 | if (!bs->bio_slab) |
| 2000 | return -ENOMEM; |
| 2001 | |
| 2002 | if (mempool_init_slab_pool(&bs->bio_pool, pool_size, bs->bio_slab)) |
| 2003 | goto bad; |
| 2004 | |
| 2005 | if ((flags & BIOSET_NEED_BVECS) && |
| 2006 | biovec_init_pool(&bs->bvec_pool, pool_size)) |
| 2007 | goto bad; |
| 2008 | |
| 2009 | if (!(flags & BIOSET_NEED_RESCUER)) |
| 2010 | return 0; |
| 2011 | |
| 2012 | bs->rescue_workqueue = alloc_workqueue("bioset", WQ_MEM_RECLAIM, 0); |
| 2013 | if (!bs->rescue_workqueue) |
| 2014 | goto bad; |
| 2015 | |
| 2016 | return 0; |
| 2017 | bad: |
| 2018 | bioset_exit(bs); |
| 2019 | return -ENOMEM; |
| 2020 | } |
| 2021 | EXPORT_SYMBOL(bioset_init); |
| 2022 | |
Jens Axboe | 28e89fd9 | 2018-06-07 14:42:05 -0600 | [diff] [blame] | 2023 | /* |
| 2024 | * Initialize and setup a new bio_set, based on the settings from |
| 2025 | * another bio_set. |
| 2026 | */ |
| 2027 | int bioset_init_from_src(struct bio_set *bs, struct bio_set *src) |
| 2028 | { |
| 2029 | int flags; |
| 2030 | |
| 2031 | flags = 0; |
| 2032 | if (src->bvec_pool.min_nr) |
| 2033 | flags |= BIOSET_NEED_BVECS; |
| 2034 | if (src->rescue_workqueue) |
| 2035 | flags |= BIOSET_NEED_RESCUER; |
| 2036 | |
| 2037 | return bioset_init(bs, src->bio_pool.min_nr, src->front_pad, flags); |
| 2038 | } |
| 2039 | EXPORT_SYMBOL(bioset_init_from_src); |
| 2040 | |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2041 | #ifdef CONFIG_BLK_CGROUP |
Tejun Heo | 1d933cf | 2015-05-22 17:13:24 -0400 | [diff] [blame] | 2042 | |
| 2043 | /** |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2044 | * bio_disassociate_blkg - puts back the blkg reference if associated |
Dennis Zhou | b5f2954 | 2018-11-01 17:24:10 -0400 | [diff] [blame] | 2045 | * @bio: target bio |
Dennis Zhou | b5f2954 | 2018-11-01 17:24:10 -0400 | [diff] [blame] | 2046 | * |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2047 | * Helper to disassociate the blkg from @bio if a blkg is associated. |
Dennis Zhou | b5f2954 | 2018-11-01 17:24:10 -0400 | [diff] [blame] | 2048 | */ |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2049 | void bio_disassociate_blkg(struct bio *bio) |
Dennis Zhou | b5f2954 | 2018-11-01 17:24:10 -0400 | [diff] [blame] | 2050 | { |
Josef Bacik | 08e18ea | 2018-07-03 11:14:50 -0400 | [diff] [blame] | 2051 | if (bio->bi_blkg) { |
| 2052 | blkg_put(bio->bi_blkg); |
| 2053 | bio->bi_blkg = NULL; |
| 2054 | } |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2055 | } |
Dennis Zhou | 892ad71 | 2018-12-05 12:10:30 -0500 | [diff] [blame] | 2056 | EXPORT_SYMBOL_GPL(bio_disassociate_blkg); |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2057 | |
Paolo Valente | 20bd723 | 2016-07-27 07:22:05 +0200 | [diff] [blame] | 2058 | /** |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2059 | * __bio_associate_blkg - associate a bio with the a blkg |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2060 | * @bio: target bio |
| 2061 | * @blkg: the blkg to associate |
| 2062 | * |
Dennis Zhou | beea9da | 2018-12-05 12:10:28 -0500 | [diff] [blame] | 2063 | * This tries to associate @bio with the specified @blkg. Association failure |
| 2064 | * is handled by walking up the blkg tree. Therefore, the blkg associated can |
| 2065 | * be anything between @blkg and the root_blkg. This situation only happens |
| 2066 | * when a cgroup is dying and then the remaining bios will spill to the closest |
| 2067 | * alive blkg. |
| 2068 | * |
| 2069 | * A reference will be taken on the @blkg and will be released when @bio is |
| 2070 | * freed. |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2071 | */ |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2072 | static void __bio_associate_blkg(struct bio *bio, struct blkcg_gq *blkg) |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2073 | { |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2074 | bio_disassociate_blkg(bio); |
| 2075 | |
Dennis Zhou | 7754f66 | 2018-12-05 12:10:39 -0500 | [diff] [blame] | 2076 | bio->bi_blkg = blkg_tryget_closest(blkg); |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2077 | } |
| 2078 | |
Dennis Zhou | fd42df3 | 2018-12-05 12:10:34 -0500 | [diff] [blame] | 2079 | /** |
| 2080 | * bio_associate_blkg_from_css - associate a bio with a specified css |
| 2081 | * @bio: target bio |
| 2082 | * @css: target css |
| 2083 | * |
| 2084 | * Associate @bio with the blkg found by combining the css's blkg and the |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2085 | * request_queue of the @bio. This falls back to the queue's root_blkg if |
| 2086 | * the association fails with the css. |
Dennis Zhou | fd42df3 | 2018-12-05 12:10:34 -0500 | [diff] [blame] | 2087 | */ |
| 2088 | void bio_associate_blkg_from_css(struct bio *bio, |
| 2089 | struct cgroup_subsys_state *css) |
| 2090 | { |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2091 | struct request_queue *q = bio->bi_disk->queue; |
| 2092 | struct blkcg_gq *blkg; |
| 2093 | |
| 2094 | rcu_read_lock(); |
| 2095 | |
| 2096 | if (!css || !css->parent) |
| 2097 | blkg = q->root_blkg; |
| 2098 | else |
| 2099 | blkg = blkg_lookup_create(css_to_blkcg(css), q); |
| 2100 | |
| 2101 | __bio_associate_blkg(bio, blkg); |
| 2102 | |
| 2103 | rcu_read_unlock(); |
Dennis Zhou | fd42df3 | 2018-12-05 12:10:34 -0500 | [diff] [blame] | 2104 | } |
| 2105 | EXPORT_SYMBOL_GPL(bio_associate_blkg_from_css); |
| 2106 | |
Dennis Zhou | 6a7f6d8 | 2018-12-05 12:10:33 -0500 | [diff] [blame] | 2107 | #ifdef CONFIG_MEMCG |
| 2108 | /** |
| 2109 | * bio_associate_blkg_from_page - associate a bio with the page's blkg |
| 2110 | * @bio: target bio |
| 2111 | * @page: the page to lookup the blkcg from |
| 2112 | * |
| 2113 | * Associate @bio with the blkg from @page's owning memcg and the respective |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2114 | * request_queue. If cgroup_e_css returns %NULL, fall back to the queue's |
| 2115 | * root_blkg. |
Dennis Zhou | 6a7f6d8 | 2018-12-05 12:10:33 -0500 | [diff] [blame] | 2116 | */ |
| 2117 | void bio_associate_blkg_from_page(struct bio *bio, struct page *page) |
| 2118 | { |
| 2119 | struct cgroup_subsys_state *css; |
| 2120 | |
Dennis Zhou | 6a7f6d8 | 2018-12-05 12:10:33 -0500 | [diff] [blame] | 2121 | if (!page->mem_cgroup) |
| 2122 | return; |
| 2123 | |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2124 | rcu_read_lock(); |
| 2125 | |
| 2126 | css = cgroup_e_css(page->mem_cgroup->css.cgroup, &io_cgrp_subsys); |
| 2127 | bio_associate_blkg_from_css(bio, css); |
| 2128 | |
| 2129 | rcu_read_unlock(); |
Dennis Zhou | 6a7f6d8 | 2018-12-05 12:10:33 -0500 | [diff] [blame] | 2130 | } |
| 2131 | #endif /* CONFIG_MEMCG */ |
| 2132 | |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2133 | /** |
| 2134 | * bio_associate_blkg - associate a bio with a blkg |
| 2135 | * @bio: target bio |
| 2136 | * |
| 2137 | * Associate @bio with the blkg found from the bio's css and request_queue. |
| 2138 | * If one is not found, bio_lookup_blkg() creates the blkg. If a blkg is |
| 2139 | * already associated, the css is reused and association redone as the |
| 2140 | * request_queue may have changed. |
| 2141 | */ |
| 2142 | void bio_associate_blkg(struct bio *bio) |
| 2143 | { |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2144 | struct cgroup_subsys_state *css; |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2145 | |
| 2146 | rcu_read_lock(); |
| 2147 | |
Dennis Zhou | db6638d | 2018-12-05 12:10:35 -0500 | [diff] [blame] | 2148 | if (bio->bi_blkg) |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2149 | css = &bio_blkcg(bio)->css; |
Dennis Zhou | db6638d | 2018-12-05 12:10:35 -0500 | [diff] [blame] | 2150 | else |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2151 | css = blkcg_css(); |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2152 | |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2153 | bio_associate_blkg_from_css(bio, css); |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2154 | |
| 2155 | rcu_read_unlock(); |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2156 | } |
Dennis Zhou | 5cdf2e3 | 2018-12-05 12:10:31 -0500 | [diff] [blame] | 2157 | EXPORT_SYMBOL_GPL(bio_associate_blkg); |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2158 | |
Paolo Valente | 20bd723 | 2016-07-27 07:22:05 +0200 | [diff] [blame] | 2159 | /** |
Dennis Zhou | db6638d | 2018-12-05 12:10:35 -0500 | [diff] [blame] | 2160 | * bio_clone_blkg_association - clone blkg association from src to dst bio |
Paolo Valente | 20bd723 | 2016-07-27 07:22:05 +0200 | [diff] [blame] | 2161 | * @dst: destination bio |
| 2162 | * @src: source bio |
| 2163 | */ |
Dennis Zhou | db6638d | 2018-12-05 12:10:35 -0500 | [diff] [blame] | 2164 | void bio_clone_blkg_association(struct bio *dst, struct bio *src) |
Paolo Valente | 20bd723 | 2016-07-27 07:22:05 +0200 | [diff] [blame] | 2165 | { |
Dennis Zhou | 6ab2187 | 2018-12-19 16:43:21 -0600 | [diff] [blame] | 2166 | rcu_read_lock(); |
| 2167 | |
Dennis Zhou | fc5a828 | 2018-12-05 12:10:36 -0500 | [diff] [blame] | 2168 | if (src->bi_blkg) |
Dennis Zhou | 2268c0f | 2018-12-05 12:10:29 -0500 | [diff] [blame] | 2169 | __bio_associate_blkg(dst, src->bi_blkg); |
Dennis Zhou | 6ab2187 | 2018-12-19 16:43:21 -0600 | [diff] [blame] | 2170 | |
| 2171 | rcu_read_unlock(); |
Paolo Valente | 20bd723 | 2016-07-27 07:22:05 +0200 | [diff] [blame] | 2172 | } |
Dennis Zhou | db6638d | 2018-12-05 12:10:35 -0500 | [diff] [blame] | 2173 | EXPORT_SYMBOL_GPL(bio_clone_blkg_association); |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 2174 | #endif /* CONFIG_BLK_CGROUP */ |
| 2175 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2176 | static void __init biovec_init_slabs(void) |
| 2177 | { |
| 2178 | int i; |
| 2179 | |
Christoph Hellwig | ed996a5 | 2016-07-19 11:28:42 +0200 | [diff] [blame] | 2180 | for (i = 0; i < BVEC_POOL_NR; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2181 | int size; |
| 2182 | struct biovec_slab *bvs = bvec_slabs + i; |
| 2183 | |
Jens Axboe | a7fcd37 | 2008-12-05 16:10:29 +0100 | [diff] [blame] | 2184 | if (bvs->nr_vecs <= BIO_INLINE_VECS) { |
| 2185 | bvs->slab = NULL; |
| 2186 | continue; |
| 2187 | } |
Jens Axboe | a7fcd37 | 2008-12-05 16:10:29 +0100 | [diff] [blame] | 2188 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2189 | size = bvs->nr_vecs * sizeof(struct bio_vec); |
| 2190 | bvs->slab = kmem_cache_create(bvs->name, size, 0, |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 2191 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2192 | } |
| 2193 | } |
| 2194 | |
| 2195 | static int __init init_bio(void) |
| 2196 | { |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 2197 | bio_slab_max = 2; |
| 2198 | bio_slab_nr = 0; |
Kees Cook | 6396bb2 | 2018-06-12 14:03:40 -0700 | [diff] [blame] | 2199 | bio_slabs = kcalloc(bio_slab_max, sizeof(struct bio_slab), |
| 2200 | GFP_KERNEL); |
Johannes Thumshirn | 2b24e6f | 2019-04-03 11:15:19 +0200 | [diff] [blame] | 2201 | |
| 2202 | BUILD_BUG_ON(BIO_FLAG_LAST > BVEC_POOL_OFFSET); |
| 2203 | |
Jens Axboe | bb799ca | 2008-12-10 15:35:05 +0100 | [diff] [blame] | 2204 | if (!bio_slabs) |
| 2205 | panic("bio: can't allocate bios\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2206 | |
Martin K. Petersen | 7878cba | 2009-06-26 15:37:49 +0200 | [diff] [blame] | 2207 | bio_integrity_init(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2208 | biovec_init_slabs(); |
| 2209 | |
Kent Overstreet | f4f8154 | 2018-05-08 21:33:52 -0400 | [diff] [blame] | 2210 | if (bioset_init(&fs_bio_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2211 | panic("bio: can't allocate bios\n"); |
| 2212 | |
Kent Overstreet | f4f8154 | 2018-05-08 21:33:52 -0400 | [diff] [blame] | 2213 | if (bioset_integrity_create(&fs_bio_set, BIO_POOL_SIZE)) |
Martin K. Petersen | a91a278 | 2011-03-17 11:11:05 +0100 | [diff] [blame] | 2214 | panic("bio: can't create integrity pool\n"); |
| 2215 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2216 | return 0; |
| 2217 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2218 | subsys_initcall(init_bio); |