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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]

Diff markup

Differences between /linux/fs/bio.c (Version 2.6.25.8) and /linux/fs/bio.c (Version 2.6.31.13)


  1 /*                                                  1 /*
  2  * Copyright (C) 2001 Jens Axboe <axboe@kernel      2  * Copyright (C) 2001 Jens Axboe <axboe@kernel.dk>
  3  *                                                  3  *
  4  * This program is free software; you can redi      4  * This program is free software; you can redistribute it and/or modify
  5  * it under the terms of the GNU General Publi      5  * it under the terms of the GNU General Public License version 2 as
  6  * published by the Free Software Foundation.       6  * published by the Free Software Foundation.
  7  *                                                  7  *
  8  * This program is distributed in the hope tha      8  * This program is distributed in the hope that it will be useful,
  9  * but WITHOUT ANY WARRANTY; without even the       9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR     10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 11  * GNU General Public License for more details     11  * GNU General Public License for more details.
 12  *                                                 12  *
 13  * You should have received a copy of the GNU      13  * You should have received a copy of the GNU General Public Licens
 14  * along with this program; if not, write to t     14  * along with this program; if not, write to the Free Software
 15  * Foundation, Inc., 59 Temple Place, Suite 33     15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
 16  *                                                 16  *
 17  */                                                17  */
 18 #include <linux/mm.h>                              18 #include <linux/mm.h>
 19 #include <linux/swap.h>                            19 #include <linux/swap.h>
 20 #include <linux/bio.h>                             20 #include <linux/bio.h>
 21 #include <linux/blkdev.h>                          21 #include <linux/blkdev.h>
 22 #include <linux/slab.h>                            22 #include <linux/slab.h>
 23 #include <linux/init.h>                            23 #include <linux/init.h>
 24 #include <linux/kernel.h>                          24 #include <linux/kernel.h>
 25 #include <linux/module.h>                          25 #include <linux/module.h>
 26 #include <linux/mempool.h>                         26 #include <linux/mempool.h>
 27 #include <linux/workqueue.h>                       27 #include <linux/workqueue.h>
 28 #include <linux/blktrace_api.h>                << 
 29 #include <scsi/sg.h>            /* for struct      28 #include <scsi/sg.h>            /* for struct sg_iovec */
 30                                                    29 
 31 #define BIO_POOL_SIZE 2                        !!  30 #include <trace/events/block.h>
 32                                                << 
 33 static struct kmem_cache *bio_slab __read_most << 
 34                                                << 
 35 #define BIOVEC_NR_POOLS 6                      << 
 36                                                    31 
 37 /*                                                 32 /*
 38  * a small number of entries is fine, not goin !!  33  * Test patch to inline a certain number of bi_io_vec's inside the bio
 39  * basically we just need to survive           !!  34  * itself, to shrink a bio data allocation from two mempool calls to one
 40  */                                                35  */
 41 #define BIO_SPLIT_ENTRIES 2                    !!  36 #define BIO_INLINE_VECS         4
 42 mempool_t *bio_split_pool __read_mostly;       << 
 43                                                    37 
 44 struct biovec_slab {                           !!  38 static mempool_t *bio_split_pool __read_mostly;
 45         int nr_vecs;                           << 
 46         char *name;                            << 
 47         struct kmem_cache *slab;               << 
 48 };                                             << 
 49                                                    39 
 50 /*                                                 40 /*
 51  * if you change this list, also change bvec_a     41  * if you change this list, also change bvec_alloc or things will
 52  * break badly! cannot be bigger than what you     42  * break badly! cannot be bigger than what you can fit into an
 53  * unsigned short                                  43  * unsigned short
 54  */                                                44  */
 55                                                << 
 56 #define BV(x) { .nr_vecs = x, .name = "biovec-     45 #define BV(x) { .nr_vecs = x, .name = "biovec-"__stringify(x) }
 57 static struct biovec_slab bvec_slabs[BIOVEC_NR !!  46 struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly = {
 58         BV(1), BV(4), BV(16), BV(64), BV(128),     47         BV(1), BV(4), BV(16), BV(64), BV(128), BV(BIO_MAX_PAGES),
 59 };                                                 48 };
 60 #undef BV                                          49 #undef BV
 61                                                    50 
 62 /*                                                 51 /*
 63  * bio_set is used to allow other portions of  << 
 64  * allocate their own private memory pools for << 
 65  * These memory pools in turn all allocate fro << 
 66  * and the bvec_slabs[].                       << 
 67  */                                            << 
 68 struct bio_set {                               << 
 69         mempool_t *bio_pool;                   << 
 70         mempool_t *bvec_pools[BIOVEC_NR_POOLS] << 
 71 };                                             << 
 72                                                << 
 73 /*                                             << 
 74  * fs_bio_set is the bio_set containing bio an     52  * fs_bio_set is the bio_set containing bio and iovec memory pools used by
 75  * IO code that does not need private memory p     53  * IO code that does not need private memory pools.
 76  */                                                54  */
 77 static struct bio_set *fs_bio_set;             !!  55 struct bio_set *fs_bio_set;
                                                   >>  56 
                                                   >>  57 /*
                                                   >>  58  * Our slab pool management
                                                   >>  59  */
                                                   >>  60 struct bio_slab {
                                                   >>  61         struct kmem_cache *slab;
                                                   >>  62         unsigned int slab_ref;
                                                   >>  63         unsigned int slab_size;
                                                   >>  64         char name[8];
                                                   >>  65 };
                                                   >>  66 static DEFINE_MUTEX(bio_slab_lock);
                                                   >>  67 static struct bio_slab *bio_slabs;
                                                   >>  68 static unsigned int bio_slab_nr, bio_slab_max;
                                                   >>  69 
                                                   >>  70 static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size)
                                                   >>  71 {
                                                   >>  72         unsigned int sz = sizeof(struct bio) + extra_size;
                                                   >>  73         struct kmem_cache *slab = NULL;
                                                   >>  74         struct bio_slab *bslab;
                                                   >>  75         unsigned int i, entry = -1;
                                                   >>  76 
                                                   >>  77         mutex_lock(&bio_slab_lock);
                                                   >>  78 
                                                   >>  79         i = 0;
                                                   >>  80         while (i < bio_slab_nr) {
                                                   >>  81                 struct bio_slab *bslab = &bio_slabs[i];
                                                   >>  82 
                                                   >>  83                 if (!bslab->slab && entry == -1)
                                                   >>  84                         entry = i;
                                                   >>  85                 else if (bslab->slab_size == sz) {
                                                   >>  86                         slab = bslab->slab;
                                                   >>  87                         bslab->slab_ref++;
                                                   >>  88                         break;
                                                   >>  89                 }
                                                   >>  90                 i++;
                                                   >>  91         }
                                                   >>  92 
                                                   >>  93         if (slab)
                                                   >>  94                 goto out_unlock;
                                                   >>  95 
                                                   >>  96         if (bio_slab_nr == bio_slab_max && entry == -1) {
                                                   >>  97                 bio_slab_max <<= 1;
                                                   >>  98                 bio_slabs = krealloc(bio_slabs,
                                                   >>  99                                      bio_slab_max * sizeof(struct bio_slab),
                                                   >> 100                                      GFP_KERNEL);
                                                   >> 101                 if (!bio_slabs)
                                                   >> 102                         goto out_unlock;
                                                   >> 103         }
                                                   >> 104         if (entry == -1)
                                                   >> 105                 entry = bio_slab_nr++;
                                                   >> 106 
                                                   >> 107         bslab = &bio_slabs[entry];
                                                   >> 108 
                                                   >> 109         snprintf(bslab->name, sizeof(bslab->name), "bio-%d", entry);
                                                   >> 110         slab = kmem_cache_create(bslab->name, sz, 0, SLAB_HWCACHE_ALIGN, NULL);
                                                   >> 111         if (!slab)
                                                   >> 112                 goto out_unlock;
                                                   >> 113 
                                                   >> 114         printk("bio: create slab <%s> at %d\n", bslab->name, entry);
                                                   >> 115         bslab->slab = slab;
                                                   >> 116         bslab->slab_ref = 1;
                                                   >> 117         bslab->slab_size = sz;
                                                   >> 118 out_unlock:
                                                   >> 119         mutex_unlock(&bio_slab_lock);
                                                   >> 120         return slab;
                                                   >> 121 }
                                                   >> 122 
                                                   >> 123 static void bio_put_slab(struct bio_set *bs)
                                                   >> 124 {
                                                   >> 125         struct bio_slab *bslab = NULL;
                                                   >> 126         unsigned int i;
                                                   >> 127 
                                                   >> 128         mutex_lock(&bio_slab_lock);
                                                   >> 129 
                                                   >> 130         for (i = 0; i < bio_slab_nr; i++) {
                                                   >> 131                 if (bs->bio_slab == bio_slabs[i].slab) {
                                                   >> 132                         bslab = &bio_slabs[i];
                                                   >> 133                         break;
                                                   >> 134                 }
                                                   >> 135         }
                                                   >> 136 
                                                   >> 137         if (WARN(!bslab, KERN_ERR "bio: unable to find slab!\n"))
                                                   >> 138                 goto out;
                                                   >> 139 
                                                   >> 140         WARN_ON(!bslab->slab_ref);
                                                   >> 141 
                                                   >> 142         if (--bslab->slab_ref)
                                                   >> 143                 goto out;
                                                   >> 144 
                                                   >> 145         kmem_cache_destroy(bslab->slab);
                                                   >> 146         bslab->slab = NULL;
 78                                                   147 
 79 static inline struct bio_vec *bvec_alloc_bs(gf !! 148 out:
                                                   >> 149         mutex_unlock(&bio_slab_lock);
                                                   >> 150 }
                                                   >> 151 
                                                   >> 152 unsigned int bvec_nr_vecs(unsigned short idx)
                                                   >> 153 {
                                                   >> 154         return bvec_slabs[idx].nr_vecs;
                                                   >> 155 }
                                                   >> 156 
                                                   >> 157 void bvec_free_bs(struct bio_set *bs, struct bio_vec *bv, unsigned int idx)
                                                   >> 158 {
                                                   >> 159         BIO_BUG_ON(idx >= BIOVEC_NR_POOLS);
                                                   >> 160 
                                                   >> 161         if (idx == BIOVEC_MAX_IDX)
                                                   >> 162                 mempool_free(bv, bs->bvec_pool);
                                                   >> 163         else {
                                                   >> 164                 struct biovec_slab *bvs = bvec_slabs + idx;
                                                   >> 165 
                                                   >> 166                 kmem_cache_free(bvs->slab, bv);
                                                   >> 167         }
                                                   >> 168 }
                                                   >> 169 
                                                   >> 170 struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx,
                                                   >> 171                               struct bio_set *bs)
 80 {                                                 172 {
 81         struct bio_vec *bvl;                      173         struct bio_vec *bvl;
 82                                                   174 
 83         /*                                        175         /*
 84          * see comment near bvec_array define!    176          * see comment near bvec_array define!
 85          */                                       177          */
 86         switch (nr) {                             178         switch (nr) {
 87                 case   1        : *idx = 0; br !! 179         case 1:
 88                 case   2 ...   4: *idx = 1; br !! 180                 *idx = 0;
 89                 case   5 ...  16: *idx = 2; br !! 181                 break;
 90                 case  17 ...  64: *idx = 3; br !! 182         case 2 ... 4:
 91                 case  65 ... 128: *idx = 4; br !! 183                 *idx = 1;
 92                 case 129 ... BIO_MAX_PAGES: *i !! 184                 break;
 93                 default:                       !! 185         case 5 ... 16:
 94                         return NULL;           !! 186                 *idx = 2;
                                                   >> 187                 break;
                                                   >> 188         case 17 ... 64:
                                                   >> 189                 *idx = 3;
                                                   >> 190                 break;
                                                   >> 191         case 65 ... 128:
                                                   >> 192                 *idx = 4;
                                                   >> 193                 break;
                                                   >> 194         case 129 ... BIO_MAX_PAGES:
                                                   >> 195                 *idx = 5;
                                                   >> 196                 break;
                                                   >> 197         default:
                                                   >> 198                 return NULL;
 95         }                                         199         }
                                                   >> 200 
 96         /*                                        201         /*
 97          * idx now points to the pool we want  !! 202          * idx now points to the pool we want to allocate from. only the
                                                   >> 203          * 1-vec entry pool is mempool backed.
 98          */                                       204          */
                                                   >> 205         if (*idx == BIOVEC_MAX_IDX) {
                                                   >> 206 fallback:
                                                   >> 207                 bvl = mempool_alloc(bs->bvec_pool, gfp_mask);
                                                   >> 208         } else {
                                                   >> 209                 struct biovec_slab *bvs = bvec_slabs + *idx;
                                                   >> 210                 gfp_t __gfp_mask = gfp_mask & ~(__GFP_WAIT | __GFP_IO);
 99                                                   211 
100         bvl = mempool_alloc(bs->bvec_pools[*id !! 212                 /*
101         if (bvl) {                             !! 213                  * Make this allocation restricted and don't dump info on
102                 struct biovec_slab *bp = bvec_ !! 214                  * allocation failures, since we'll fallback to the mempool
                                                   >> 215                  * in case of failure.
                                                   >> 216                  */
                                                   >> 217                 __gfp_mask |= __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN;
103                                                   218 
104                 memset(bvl, 0, bp->nr_vecs * s !! 219                 /*
                                                   >> 220                  * Try a slab allocation. If this fails and __GFP_WAIT
                                                   >> 221                  * is set, retry with the 1-entry mempool
                                                   >> 222                  */
                                                   >> 223                 bvl = kmem_cache_alloc(bvs->slab, __gfp_mask);
                                                   >> 224                 if (unlikely(!bvl && (gfp_mask & __GFP_WAIT))) {
                                                   >> 225                         *idx = BIOVEC_MAX_IDX;
                                                   >> 226                         goto fallback;
                                                   >> 227                 }
105         }                                         228         }
106                                                   229 
107         return bvl;                               230         return bvl;
108 }                                                 231 }
109                                                   232 
110 void bio_free(struct bio *bio, struct bio_set  !! 233 void bio_free(struct bio *bio, struct bio_set *bs)
111 {                                                 234 {
112         if (bio->bi_io_vec) {                  !! 235         void *p;
113                 const int pool_idx = BIO_POOL_ << 
114                                                   236 
115                 BIO_BUG_ON(pool_idx >= BIOVEC_ !! 237         if (bio_has_allocated_vec(bio))
                                                   >> 238                 bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio));
116                                                   239 
117                 mempool_free(bio->bi_io_vec, b !! 240         if (bio_integrity(bio))
118         }                                      !! 241                 bio_integrity_free(bio, bs);
119                                                   242 
120         mempool_free(bio, bio_set->bio_pool);  !! 243         /*
121 }                                              !! 244          * If we have front padding, adjust the bio pointer before freeing
                                                   >> 245          */
                                                   >> 246         p = bio;
                                                   >> 247         if (bs->front_pad)
                                                   >> 248                 p -= bs->front_pad;
122                                                   249 
123 /*                                             !! 250         mempool_free(p, bs->bio_pool);
124  * default destructor for a bio allocated with << 
125  */                                            << 
126 static void bio_fs_destructor(struct bio *bio) << 
127 {                                              << 
128         bio_free(bio, fs_bio_set);             << 
129 }                                                 251 }
130                                                   252 
131 void bio_init(struct bio *bio)                    253 void bio_init(struct bio *bio)
132 {                                                 254 {
133         memset(bio, 0, sizeof(*bio));             255         memset(bio, 0, sizeof(*bio));
134         bio->bi_flags = 1 << BIO_UPTODATE;        256         bio->bi_flags = 1 << BIO_UPTODATE;
                                                   >> 257         bio->bi_comp_cpu = -1;
135         atomic_set(&bio->bi_cnt, 1);              258         atomic_set(&bio->bi_cnt, 1);
136 }                                                 259 }
137                                                   260 
138 /**                                               261 /**
139  * bio_alloc_bioset - allocate a bio for I/O      262  * bio_alloc_bioset - allocate a bio for I/O
140  * @gfp_mask:   the GFP_ mask given to the sla    263  * @gfp_mask:   the GFP_ mask given to the slab allocator
141  * @nr_iovecs:  number of iovecs to pre-alloca    264  * @nr_iovecs:  number of iovecs to pre-allocate
142  * @bs:         the bio_set to allocate from   !! 265  * @bs:         the bio_set to allocate from. If %NULL, just use kmalloc
143  *                                                266  *
144  * Description:                                   267  * Description:
145  *   bio_alloc_bioset will first try it's on m !! 268  *   bio_alloc_bioset will first try its own mempool to satisfy the allocation.
146  *   If %__GFP_WAIT is set then we will block     269  *   If %__GFP_WAIT is set then we will block on the internal pool waiting
147  *   for a &struct bio to become free.         !! 270  *   for a &struct bio to become free. If a %NULL @bs is passed in, we will
                                                   >> 271  *   fall back to just using @kmalloc to allocate the required memory.
148  *                                                272  *
149  *   allocate bio and iovecs from the memory p !! 273  *   Note that the caller must set ->bi_destructor on succesful return
150  *   bio_set structure.                        !! 274  *   of a bio, to do the appropriate freeing of the bio once the reference
                                                   >> 275  *   count drops to zero.
151  **/                                              276  **/
152 struct bio *bio_alloc_bioset(gfp_t gfp_mask, i    277 struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs)
153 {                                                 278 {
154         struct bio *bio = mempool_alloc(bs->bi !! 279         unsigned long idx = BIO_POOL_NONE;
                                                   >> 280         struct bio_vec *bvl = NULL;
                                                   >> 281         struct bio *bio;
                                                   >> 282         void *p;
155                                                   283 
156         if (likely(bio)) {                     !! 284         p = mempool_alloc(bs->bio_pool, gfp_mask);
157                 struct bio_vec *bvl = NULL;    !! 285         if (unlikely(!p))
                                                   >> 286                 return NULL;
                                                   >> 287         bio = p + bs->front_pad;
158                                                   288 
159                 bio_init(bio);                 !! 289         bio_init(bio);
160                 if (likely(nr_iovecs)) {       !! 290 
161                         unsigned long idx = 0; !! 291         if (unlikely(!nr_iovecs))
162                                                !! 292                 goto out_set;
163                         bvl = bvec_alloc_bs(gf !! 293 
164                         if (unlikely(!bvl)) {  !! 294         if (nr_iovecs <= BIO_INLINE_VECS) {
165                                 mempool_free(b !! 295                 bvl = bio->bi_inline_vecs;
166                                 bio = NULL;    !! 296                 nr_iovecs = BIO_INLINE_VECS;
167                                 goto out;      !! 297         } else {
168                         }                      !! 298                 bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs);
169                         bio->bi_flags |= idx < !! 299                 if (unlikely(!bvl))
170                         bio->bi_max_vecs = bve !! 300                         goto err_free;
171                 }                              !! 301 
172                 bio->bi_io_vec = bvl;          !! 302                 nr_iovecs = bvec_nr_vecs(idx);
173         }                                      !! 303         }
174 out:                                           !! 304 out_set:
                                                   >> 305         bio->bi_flags |= idx << BIO_POOL_OFFSET;
                                                   >> 306         bio->bi_max_vecs = nr_iovecs;
                                                   >> 307         bio->bi_io_vec = bvl;
175         return bio;                               308         return bio;
                                                   >> 309 
                                                   >> 310 err_free:
                                                   >> 311         mempool_free(p, bs->bio_pool);
                                                   >> 312         return NULL;
                                                   >> 313 }
                                                   >> 314 
                                                   >> 315 static void bio_fs_destructor(struct bio *bio)
                                                   >> 316 {
                                                   >> 317         bio_free(bio, fs_bio_set);
176 }                                                 318 }
177                                                   319 
                                                   >> 320 /**
                                                   >> 321  *      bio_alloc - allocate a new bio, memory pool backed
                                                   >> 322  *      @gfp_mask: allocation mask to use
                                                   >> 323  *      @nr_iovecs: number of iovecs
                                                   >> 324  *
                                                   >> 325  *      Allocate a new bio with @nr_iovecs bvecs.  If @gfp_mask
                                                   >> 326  *      contains __GFP_WAIT, the allocation is guaranteed to succeed.
                                                   >> 327  *
                                                   >> 328  *      RETURNS:
                                                   >> 329  *      Pointer to new bio on success, NULL on failure.
                                                   >> 330  */
178 struct bio *bio_alloc(gfp_t gfp_mask, int nr_i    331 struct bio *bio_alloc(gfp_t gfp_mask, int nr_iovecs)
179 {                                                 332 {
180         struct bio *bio = bio_alloc_bioset(gfp    333         struct bio *bio = bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
181                                                   334 
182         if (bio)                                  335         if (bio)
183                 bio->bi_destructor = bio_fs_de    336                 bio->bi_destructor = bio_fs_destructor;
184                                                   337 
185         return bio;                               338         return bio;
186 }                                                 339 }
187                                                   340 
                                                   >> 341 static void bio_kmalloc_destructor(struct bio *bio)
                                                   >> 342 {
                                                   >> 343         if (bio_integrity(bio))
                                                   >> 344                 bio_integrity_free(bio, fs_bio_set);
                                                   >> 345         kfree(bio);
                                                   >> 346 }
                                                   >> 347 
                                                   >> 348 /**
                                                   >> 349  * bio_alloc - allocate a bio for I/O
                                                   >> 350  * @gfp_mask:   the GFP_ mask given to the slab allocator
                                                   >> 351  * @nr_iovecs:  number of iovecs to pre-allocate
                                                   >> 352  *
                                                   >> 353  * Description:
                                                   >> 354  *   bio_alloc will allocate a bio and associated bio_vec array that can hold
                                                   >> 355  *   at least @nr_iovecs entries. Allocations will be done from the
                                                   >> 356  *   fs_bio_set. Also see @bio_alloc_bioset.
                                                   >> 357  *
                                                   >> 358  *   If %__GFP_WAIT is set, then bio_alloc will always be able to allocate
                                                   >> 359  *   a bio. This is due to the mempool guarantees. To make this work, callers
                                                   >> 360  *   must never allocate more than 1 bio at a time from this pool. Callers
                                                   >> 361  *   that need to allocate more than 1 bio must always submit the previously
                                                   >> 362  *   allocated bio for IO before attempting to allocate a new one. Failure to
                                                   >> 363  *   do so can cause livelocks under memory pressure.
                                                   >> 364  *
                                                   >> 365  **/
                                                   >> 366 struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs)
                                                   >> 367 {
                                                   >> 368         struct bio *bio;
                                                   >> 369 
                                                   >> 370         bio = kmalloc(sizeof(struct bio) + nr_iovecs * sizeof(struct bio_vec),
                                                   >> 371                       gfp_mask);
                                                   >> 372         if (unlikely(!bio))
                                                   >> 373                 return NULL;
                                                   >> 374 
                                                   >> 375         bio_init(bio);
                                                   >> 376         bio->bi_flags |= BIO_POOL_NONE << BIO_POOL_OFFSET;
                                                   >> 377         bio->bi_max_vecs = nr_iovecs;
                                                   >> 378         bio->bi_io_vec = bio->bi_inline_vecs;
                                                   >> 379         bio->bi_destructor = bio_kmalloc_destructor;
                                                   >> 380 
                                                   >> 381         return bio;
                                                   >> 382 }
                                                   >> 383 
188 void zero_fill_bio(struct bio *bio)               384 void zero_fill_bio(struct bio *bio)
189 {                                                 385 {
190         unsigned long flags;                      386         unsigned long flags;
191         struct bio_vec *bv;                       387         struct bio_vec *bv;
192         int i;                                    388         int i;
193                                                   389 
194         bio_for_each_segment(bv, bio, i) {        390         bio_for_each_segment(bv, bio, i) {
195                 char *data = bvec_kmap_irq(bv,    391                 char *data = bvec_kmap_irq(bv, &flags);
196                 memset(data, 0, bv->bv_len);      392                 memset(data, 0, bv->bv_len);
197                 flush_dcache_page(bv->bv_page)    393                 flush_dcache_page(bv->bv_page);
198                 bvec_kunmap_irq(data, &flags);    394                 bvec_kunmap_irq(data, &flags);
199         }                                         395         }
200 }                                                 396 }
201 EXPORT_SYMBOL(zero_fill_bio);                     397 EXPORT_SYMBOL(zero_fill_bio);
202                                                   398 
203 /**                                               399 /**
204  * bio_put - release a reference to a bio         400  * bio_put - release a reference to a bio
205  * @bio:   bio to release reference to            401  * @bio:   bio to release reference to
206  *                                                402  *
207  * Description:                                   403  * Description:
208  *   Put a reference to a &struct bio, either     404  *   Put a reference to a &struct bio, either one you have gotten with
209  *   bio_alloc or bio_get. The last put of a b    405  *   bio_alloc or bio_get. The last put of a bio will free it.
210  **/                                              406  **/
211 void bio_put(struct bio *bio)                     407 void bio_put(struct bio *bio)
212 {                                                 408 {
213         BIO_BUG_ON(!atomic_read(&bio->bi_cnt))    409         BIO_BUG_ON(!atomic_read(&bio->bi_cnt));
214                                                   410 
215         /*                                        411         /*
216          * last put frees it                      412          * last put frees it
217          */                                       413          */
218         if (atomic_dec_and_test(&bio->bi_cnt))    414         if (atomic_dec_and_test(&bio->bi_cnt)) {
219                 bio->bi_next = NULL;              415                 bio->bi_next = NULL;
220                 bio->bi_destructor(bio);          416                 bio->bi_destructor(bio);
221         }                                         417         }
222 }                                                 418 }
223                                                   419 
224 inline int bio_phys_segments(struct request_qu    420 inline int bio_phys_segments(struct request_queue *q, struct bio *bio)
225 {                                                 421 {
226         if (unlikely(!bio_flagged(bio, BIO_SEG    422         if (unlikely(!bio_flagged(bio, BIO_SEG_VALID)))
227                 blk_recount_segments(q, bio);     423                 blk_recount_segments(q, bio);
228                                                   424 
229         return bio->bi_phys_segments;             425         return bio->bi_phys_segments;
230 }                                                 426 }
231                                                   427 
232 inline int bio_hw_segments(struct request_queu << 
233 {                                              << 
234         if (unlikely(!bio_flagged(bio, BIO_SEG << 
235                 blk_recount_segments(q, bio);  << 
236                                                << 
237         return bio->bi_hw_segments;            << 
238 }                                              << 
239                                                << 
240 /**                                               428 /**
241  *      __bio_clone     -       clone a bio       429  *      __bio_clone     -       clone a bio
242  *      @bio: destination bio                     430  *      @bio: destination bio
243  *      @bio_src: bio to clone                    431  *      @bio_src: bio to clone
244  *                                                432  *
245  *      Clone a &bio. Caller will own the retu    433  *      Clone a &bio. Caller will own the returned bio, but not
246  *      the actual data it points to. Referenc    434  *      the actual data it points to. Reference count of returned
247  *      bio will be one.                          435  *      bio will be one.
248  */                                               436  */
249 void __bio_clone(struct bio *bio, struct bio *    437 void __bio_clone(struct bio *bio, struct bio *bio_src)
250 {                                                 438 {
251         memcpy(bio->bi_io_vec, bio_src->bi_io_    439         memcpy(bio->bi_io_vec, bio_src->bi_io_vec,
252                 bio_src->bi_max_vecs * sizeof(    440                 bio_src->bi_max_vecs * sizeof(struct bio_vec));
253                                                   441 
254         /*                                        442         /*
255          * most users will be overriding ->bi_    443          * most users will be overriding ->bi_bdev with a new target,
256          * so we don't set nor calculate new p    444          * so we don't set nor calculate new physical/hw segment counts here
257          */                                       445          */
258         bio->bi_sector = bio_src->bi_sector;      446         bio->bi_sector = bio_src->bi_sector;
259         bio->bi_bdev = bio_src->bi_bdev;          447         bio->bi_bdev = bio_src->bi_bdev;
260         bio->bi_flags |= 1 << BIO_CLONED;         448         bio->bi_flags |= 1 << BIO_CLONED;
261         bio->bi_rw = bio_src->bi_rw;              449         bio->bi_rw = bio_src->bi_rw;
262         bio->bi_vcnt = bio_src->bi_vcnt;          450         bio->bi_vcnt = bio_src->bi_vcnt;
263         bio->bi_size = bio_src->bi_size;          451         bio->bi_size = bio_src->bi_size;
264         bio->bi_idx = bio_src->bi_idx;            452         bio->bi_idx = bio_src->bi_idx;
265 }                                                 453 }
266                                                   454 
267 /**                                               455 /**
268  *      bio_clone       -       clone a bio       456  *      bio_clone       -       clone a bio
269  *      @bio: bio to clone                        457  *      @bio: bio to clone
270  *      @gfp_mask: allocation priority            458  *      @gfp_mask: allocation priority
271  *                                                459  *
272  *      Like __bio_clone, only also allocates     460  *      Like __bio_clone, only also allocates the returned bio
273  */                                               461  */
274 struct bio *bio_clone(struct bio *bio, gfp_t g    462 struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
275 {                                                 463 {
276         struct bio *b = bio_alloc_bioset(gfp_m    464         struct bio *b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs, fs_bio_set);
277                                                   465 
278         if (b) {                               !! 466         if (!b)
279                 b->bi_destructor = bio_fs_dest !! 467                 return NULL;
280                 __bio_clone(b, bio);           !! 468 
                                                   >> 469         b->bi_destructor = bio_fs_destructor;
                                                   >> 470         __bio_clone(b, bio);
                                                   >> 471 
                                                   >> 472         if (bio_integrity(bio)) {
                                                   >> 473                 int ret;
                                                   >> 474 
                                                   >> 475                 ret = bio_integrity_clone(b, bio, gfp_mask, fs_bio_set);
                                                   >> 476 
                                                   >> 477                 if (ret < 0) {
                                                   >> 478                         bio_put(b);
                                                   >> 479                         return NULL;
                                                   >> 480                 }
281         }                                         481         }
282                                                   482 
283         return b;                                 483         return b;
284 }                                                 484 }
285                                                   485 
286 /**                                               486 /**
287  *      bio_get_nr_vecs         - return appro    487  *      bio_get_nr_vecs         - return approx number of vecs
288  *      @bdev:  I/O target                        488  *      @bdev:  I/O target
289  *                                                489  *
290  *      Return the approximate number of pages    490  *      Return the approximate number of pages we can send to this target.
291  *      There's no guarantee that you will be     491  *      There's no guarantee that you will be able to fit this number of pages
292  *      into a bio, it does not account for dy    492  *      into a bio, it does not account for dynamic restrictions that vary
293  *      on offset.                                493  *      on offset.
294  */                                               494  */
295 int bio_get_nr_vecs(struct block_device *bdev)    495 int bio_get_nr_vecs(struct block_device *bdev)
296 {                                                 496 {
297         struct request_queue *q = bdev_get_que    497         struct request_queue *q = bdev_get_queue(bdev);
298         int nr_pages;                             498         int nr_pages;
299                                                   499 
300         nr_pages = ((q->max_sectors << 9) + PA !! 500         nr_pages = ((queue_max_sectors(q) << 9) + PAGE_SIZE - 1) >> PAGE_SHIFT;
301         if (nr_pages > q->max_phys_segments)   !! 501         if (nr_pages > queue_max_phys_segments(q))
302                 nr_pages = q->max_phys_segment !! 502                 nr_pages = queue_max_phys_segments(q);
303         if (nr_pages > q->max_hw_segments)     !! 503         if (nr_pages > queue_max_hw_segments(q))
304                 nr_pages = q->max_hw_segments; !! 504                 nr_pages = queue_max_hw_segments(q);
305                                                   505 
306         return nr_pages;                          506         return nr_pages;
307 }                                                 507 }
308                                                   508 
309 static int __bio_add_page(struct request_queue    509 static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
310                           *page, unsigned int     510                           *page, unsigned int len, unsigned int offset,
311                           unsigned short max_s    511                           unsigned short max_sectors)
312 {                                                 512 {
313         int retried_segments = 0;                 513         int retried_segments = 0;
314         struct bio_vec *bvec;                     514         struct bio_vec *bvec;
315                                                   515 
316         /*                                        516         /*
317          * cloned bio must not modify vec list    517          * cloned bio must not modify vec list
318          */                                       518          */
319         if (unlikely(bio_flagged(bio, BIO_CLON    519         if (unlikely(bio_flagged(bio, BIO_CLONED)))
320                 return 0;                         520                 return 0;
321                                                   521 
322         if (((bio->bi_size + len) >> 9) > max_    522         if (((bio->bi_size + len) >> 9) > max_sectors)
323                 return 0;                         523                 return 0;
324                                                   524 
325         /*                                        525         /*
326          * For filesystems with a blocksize sm    526          * For filesystems with a blocksize smaller than the pagesize
327          * we will often be called with the sa    527          * we will often be called with the same page as last time and
328          * a consecutive offset.  Optimize thi    528          * a consecutive offset.  Optimize this special case.
329          */                                       529          */
330         if (bio->bi_vcnt > 0) {                   530         if (bio->bi_vcnt > 0) {
331                 struct bio_vec *prev = &bio->b    531                 struct bio_vec *prev = &bio->bi_io_vec[bio->bi_vcnt - 1];
332                                                   532 
333                 if (page == prev->bv_page &&      533                 if (page == prev->bv_page &&
334                     offset == prev->bv_offset     534                     offset == prev->bv_offset + prev->bv_len) {
335                         prev->bv_len += len;      535                         prev->bv_len += len;
336                         if (q->merge_bvec_fn & !! 536 
337                             q->merge_bvec_fn(q !! 537                         if (q->merge_bvec_fn) {
338                                 prev->bv_len - !! 538                                 struct bvec_merge_data bvm = {
339                                 return 0;      !! 539                                         .bi_bdev = bio->bi_bdev,
                                                   >> 540                                         .bi_sector = bio->bi_sector,
                                                   >> 541                                         .bi_size = bio->bi_size,
                                                   >> 542                                         .bi_rw = bio->bi_rw,
                                                   >> 543                                 };
                                                   >> 544 
                                                   >> 545                                 if (q->merge_bvec_fn(q, &bvm, prev) < len) {
                                                   >> 546                                         prev->bv_len -= len;
                                                   >> 547                                         return 0;
                                                   >> 548                                 }
340                         }                         549                         }
341                                                   550 
342                         goto done;                551                         goto done;
343                 }                                 552                 }
344         }                                         553         }
345                                                   554 
346         if (bio->bi_vcnt >= bio->bi_max_vecs)     555         if (bio->bi_vcnt >= bio->bi_max_vecs)
347                 return 0;                         556                 return 0;
348                                                   557 
349         /*                                        558         /*
350          * we might lose a segment or two here    559          * we might lose a segment or two here, but rather that than
351          * make this too complex.                 560          * make this too complex.
352          */                                       561          */
353                                                   562 
354         while (bio->bi_phys_segments >= q->max !! 563         while (bio->bi_phys_segments >= queue_max_phys_segments(q)
355                || bio->bi_hw_segments >= q->ma !! 564                || bio->bi_phys_segments >= queue_max_hw_segments(q)) {
356                || BIOVEC_VIRT_OVERSIZE(bio->bi << 
357                                                   565 
358                 if (retried_segments)             566                 if (retried_segments)
359                         return 0;                 567                         return 0;
360                                                   568 
361                 retried_segments = 1;             569                 retried_segments = 1;
362                 blk_recount_segments(q, bio);     570                 blk_recount_segments(q, bio);
363         }                                         571         }
364                                                   572 
365         /*                                        573         /*
366          * setup the new entry, we might clear    574          * setup the new entry, we might clear it again later if we
367          * cannot add the page                    575          * cannot add the page
368          */                                       576          */
369         bvec = &bio->bi_io_vec[bio->bi_vcnt];     577         bvec = &bio->bi_io_vec[bio->bi_vcnt];
370         bvec->bv_page = page;                     578         bvec->bv_page = page;
371         bvec->bv_len = len;                       579         bvec->bv_len = len;
372         bvec->bv_offset = offset;                 580         bvec->bv_offset = offset;
373                                                   581 
374         /*                                        582         /*
375          * if queue has other restrictions (eg    583          * if queue has other restrictions (eg varying max sector size
376          * depending on offset), it can specif    584          * depending on offset), it can specify a merge_bvec_fn in the
377          * queue to get further control           585          * queue to get further control
378          */                                       586          */
379         if (q->merge_bvec_fn) {                   587         if (q->merge_bvec_fn) {
                                                   >> 588                 struct bvec_merge_data bvm = {
                                                   >> 589                         .bi_bdev = bio->bi_bdev,
                                                   >> 590                         .bi_sector = bio->bi_sector,
                                                   >> 591                         .bi_size = bio->bi_size,
                                                   >> 592                         .bi_rw = bio->bi_rw,
                                                   >> 593                 };
                                                   >> 594 
380                 /*                                595                 /*
381                  * merge_bvec_fn() returns num    596                  * merge_bvec_fn() returns number of bytes it can accept
382                  * at this offset                 597                  * at this offset
383                  */                               598                  */
384                 if (q->merge_bvec_fn(q, bio, b !! 599                 if (q->merge_bvec_fn(q, &bvm, bvec) < len) {
385                         bvec->bv_page = NULL;     600                         bvec->bv_page = NULL;
386                         bvec->bv_len = 0;         601                         bvec->bv_len = 0;
387                         bvec->bv_offset = 0;      602                         bvec->bv_offset = 0;
388                         return 0;                 603                         return 0;
389                 }                                 604                 }
390         }                                         605         }
391                                                   606 
392         /* If we may be able to merge these bi    607         /* If we may be able to merge these biovecs, force a recount */
393         if (bio->bi_vcnt && (BIOVEC_PHYS_MERGE !! 608         if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec)))
394             BIOVEC_VIRT_MERGEABLE(bvec-1, bvec << 
395                 bio->bi_flags &= ~(1 << BIO_SE    609                 bio->bi_flags &= ~(1 << BIO_SEG_VALID);
396                                                   610 
397         bio->bi_vcnt++;                           611         bio->bi_vcnt++;
398         bio->bi_phys_segments++;                  612         bio->bi_phys_segments++;
399         bio->bi_hw_segments++;                 << 
400  done:                                            613  done:
401         bio->bi_size += len;                      614         bio->bi_size += len;
402         return len;                               615         return len;
403 }                                                 616 }
404                                                   617 
405 /**                                               618 /**
406  *      bio_add_pc_page -       attempt to add    619  *      bio_add_pc_page -       attempt to add page to bio
407  *      @q: the target queue                      620  *      @q: the target queue
408  *      @bio: destination bio                     621  *      @bio: destination bio
409  *      @page: page to add                        622  *      @page: page to add
410  *      @len: vec entry length                    623  *      @len: vec entry length
411  *      @offset: vec entry offset                 624  *      @offset: vec entry offset
412  *                                                625  *
413  *      Attempt to add a page to the bio_vec m    626  *      Attempt to add a page to the bio_vec maplist. This can fail for a
414  *      number of reasons, such as the bio bei    627  *      number of reasons, such as the bio being full or target block
415  *      device limitations. The target block d    628  *      device limitations. The target block device must allow bio's
416  *      smaller than PAGE_SIZE, so it is alway    629  *      smaller than PAGE_SIZE, so it is always possible to add a single
417  *      page to an empty bio. This should only    630  *      page to an empty bio. This should only be used by REQ_PC bios.
418  */                                               631  */
419 int bio_add_pc_page(struct request_queue *q, s    632 int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page,
420                     unsigned int len, unsigned    633                     unsigned int len, unsigned int offset)
421 {                                                 634 {
422         return __bio_add_page(q, bio, page, le !! 635         return __bio_add_page(q, bio, page, len, offset,
                                                   >> 636                               queue_max_hw_sectors(q));
423 }                                                 637 }
424                                                   638 
425 /**                                               639 /**
426  *      bio_add_page    -       attempt to add    640  *      bio_add_page    -       attempt to add page to bio
427  *      @bio: destination bio                     641  *      @bio: destination bio
428  *      @page: page to add                        642  *      @page: page to add
429  *      @len: vec entry length                    643  *      @len: vec entry length
430  *      @offset: vec entry offset                 644  *      @offset: vec entry offset
431  *                                                645  *
432  *      Attempt to add a page to the bio_vec m    646  *      Attempt to add a page to the bio_vec maplist. This can fail for a
433  *      number of reasons, such as the bio bei    647  *      number of reasons, such as the bio being full or target block
434  *      device limitations. The target block d    648  *      device limitations. The target block device must allow bio's
435  *      smaller than PAGE_SIZE, so it is alway    649  *      smaller than PAGE_SIZE, so it is always possible to add a single
436  *      page to an empty bio.                     650  *      page to an empty bio.
437  */                                               651  */
438 int bio_add_page(struct bio *bio, struct page     652 int bio_add_page(struct bio *bio, struct page *page, unsigned int len,
439                  unsigned int offset)             653                  unsigned int offset)
440 {                                                 654 {
441         struct request_queue *q = bdev_get_que    655         struct request_queue *q = bdev_get_queue(bio->bi_bdev);
442         return __bio_add_page(q, bio, page, le !! 656         return __bio_add_page(q, bio, page, len, offset, queue_max_sectors(q));
443 }                                                 657 }
444                                                   658 
445 struct bio_map_data {                             659 struct bio_map_data {
446         struct bio_vec *iovecs;                   660         struct bio_vec *iovecs;
447         void __user *userptr;                  !! 661         struct sg_iovec *sgvecs;
                                                   >> 662         int nr_sgvecs;
                                                   >> 663         int is_our_pages;
448 };                                                664 };
449                                                   665 
450 static void bio_set_map_data(struct bio_map_da !! 666 static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio,
                                                   >> 667                              struct sg_iovec *iov, int iov_count,
                                                   >> 668                              int is_our_pages)
451 {                                                 669 {
452         memcpy(bmd->iovecs, bio->bi_io_vec, si    670         memcpy(bmd->iovecs, bio->bi_io_vec, sizeof(struct bio_vec) * bio->bi_vcnt);
                                                   >> 671         memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count);
                                                   >> 672         bmd->nr_sgvecs = iov_count;
                                                   >> 673         bmd->is_our_pages = is_our_pages;
453         bio->bi_private = bmd;                    674         bio->bi_private = bmd;
454 }                                                 675 }
455                                                   676 
456 static void bio_free_map_data(struct bio_map_d    677 static void bio_free_map_data(struct bio_map_data *bmd)
457 {                                                 678 {
458         kfree(bmd->iovecs);                       679         kfree(bmd->iovecs);
                                                   >> 680         kfree(bmd->sgvecs);
459         kfree(bmd);                               681         kfree(bmd);
460 }                                                 682 }
461                                                   683 
462 static struct bio_map_data *bio_alloc_map_data !! 684 static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count,
                                                   >> 685                                                gfp_t gfp_mask)
463 {                                                 686 {
464         struct bio_map_data *bmd = kmalloc(siz !! 687         struct bio_map_data *bmd = kmalloc(sizeof(*bmd), gfp_mask);
465                                                   688 
466         if (!bmd)                                 689         if (!bmd)
467                 return NULL;                      690                 return NULL;
468                                                   691 
469         bmd->iovecs = kmalloc(sizeof(struct bi !! 692         bmd->iovecs = kmalloc(sizeof(struct bio_vec) * nr_segs, gfp_mask);
470         if (bmd->iovecs)                       !! 693         if (!bmd->iovecs) {
                                                   >> 694                 kfree(bmd);
                                                   >> 695                 return NULL;
                                                   >> 696         }
                                                   >> 697 
                                                   >> 698         bmd->sgvecs = kmalloc(sizeof(struct sg_iovec) * iov_count, gfp_mask);
                                                   >> 699         if (bmd->sgvecs)
471                 return bmd;                       700                 return bmd;
472                                                   701 
                                                   >> 702         kfree(bmd->iovecs);
473         kfree(bmd);                               703         kfree(bmd);
474         return NULL;                              704         return NULL;
475 }                                                 705 }
476                                                   706 
                                                   >> 707 static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
                                                   >> 708                           struct sg_iovec *iov, int iov_count,
                                                   >> 709                           int to_user, int from_user, int do_free_page)
                                                   >> 710 {
                                                   >> 711         int ret = 0, i;
                                                   >> 712         struct bio_vec *bvec;
                                                   >> 713         int iov_idx = 0;
                                                   >> 714         unsigned int iov_off = 0;
                                                   >> 715 
                                                   >> 716         __bio_for_each_segment(bvec, bio, i, 0) {
                                                   >> 717                 char *bv_addr = page_address(bvec->bv_page);
                                                   >> 718                 unsigned int bv_len = iovecs[i].bv_len;
                                                   >> 719 
                                                   >> 720                 while (bv_len && iov_idx < iov_count) {
                                                   >> 721                         unsigned int bytes;
                                                   >> 722                         char __user *iov_addr;
                                                   >> 723 
                                                   >> 724                         bytes = min_t(unsigned int,
                                                   >> 725                                       iov[iov_idx].iov_len - iov_off, bv_len);
                                                   >> 726                         iov_addr = iov[iov_idx].iov_base + iov_off;
                                                   >> 727 
                                                   >> 728                         if (!ret) {
                                                   >> 729                                 if (to_user)
                                                   >> 730                                         ret = copy_to_user(iov_addr, bv_addr,
                                                   >> 731                                                            bytes);
                                                   >> 732 
                                                   >> 733                                 if (from_user)
                                                   >> 734                                         ret = copy_from_user(bv_addr, iov_addr,
                                                   >> 735                                                              bytes);
                                                   >> 736 
                                                   >> 737                                 if (ret)
                                                   >> 738                                         ret = -EFAULT;
                                                   >> 739                         }
                                                   >> 740 
                                                   >> 741                         bv_len -= bytes;
                                                   >> 742                         bv_addr += bytes;
                                                   >> 743                         iov_addr += bytes;
                                                   >> 744                         iov_off += bytes;
                                                   >> 745 
                                                   >> 746                         if (iov[iov_idx].iov_len == iov_off) {
                                                   >> 747                                 iov_idx++;
                                                   >> 748                                 iov_off = 0;
                                                   >> 749                         }
                                                   >> 750                 }
                                                   >> 751 
                                                   >> 752                 if (do_free_page)
                                                   >> 753                         __free_page(bvec->bv_page);
                                                   >> 754         }
                                                   >> 755 
                                                   >> 756         return ret;
                                                   >> 757 }
                                                   >> 758 
477 /**                                               759 /**
478  *      bio_uncopy_user -       finish previou    760  *      bio_uncopy_user -       finish previously mapped bio
479  *      @bio: bio being terminated                761  *      @bio: bio being terminated
480  *                                                762  *
481  *      Free pages allocated from bio_copy_use    763  *      Free pages allocated from bio_copy_user() and write back data
482  *      to user space in case of a read.          764  *      to user space in case of a read.
483  */                                               765  */
484 int bio_uncopy_user(struct bio *bio)              766 int bio_uncopy_user(struct bio *bio)
485 {                                                 767 {
486         struct bio_map_data *bmd = bio->bi_pri    768         struct bio_map_data *bmd = bio->bi_private;
487         const int read = bio_data_dir(bio) ==  !! 769         int ret = 0;
488         struct bio_vec *bvec;                  << 
489         int i, ret = 0;                        << 
490                                                   770 
491         __bio_for_each_segment(bvec, bio, i, 0 !! 771         if (!bio_flagged(bio, BIO_NULL_MAPPED))
492                 char *addr = page_address(bvec !! 772                 ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs,
493                 unsigned int len = bmd->iovecs !! 773                                      bmd->nr_sgvecs, bio_data_dir(bio) == READ,
494                                                !! 774                                      0, bmd->is_our_pages);
495                 if (read && !ret && copy_to_us << 
496                         ret = -EFAULT;         << 
497                                                << 
498                 __free_page(bvec->bv_page);    << 
499                 bmd->userptr += len;           << 
500         }                                      << 
501         bio_free_map_data(bmd);                   775         bio_free_map_data(bmd);
502         bio_put(bio);                             776         bio_put(bio);
503         return ret;                               777         return ret;
504 }                                                 778 }
505                                                   779 
506 /**                                               780 /**
507  *      bio_copy_user   -       copy user data !! 781  *      bio_copy_user_iov       -       copy user data to bio
508  *      @q: destination block queue               782  *      @q: destination block queue
509  *      @uaddr: start of user address          !! 783  *      @map_data: pointer to the rq_map_data holding pages (if necessary)
510  *      @len: length in bytes                  !! 784  *      @iov:   the iovec.
                                                   >> 785  *      @iov_count: number of elements in the iovec
511  *      @write_to_vm: bool indicating writing     786  *      @write_to_vm: bool indicating writing to pages or not
                                                   >> 787  *      @gfp_mask: memory allocation flags
512  *                                                788  *
513  *      Prepares and returns a bio for indirec    789  *      Prepares and returns a bio for indirect user io, bouncing data
514  *      to/from kernel pages as necessary. Mus    790  *      to/from kernel pages as necessary. Must be paired with
515  *      call bio_uncopy_user() on io completio    791  *      call bio_uncopy_user() on io completion.
516  */                                               792  */
517 struct bio *bio_copy_user(struct request_queue !! 793 struct bio *bio_copy_user_iov(struct request_queue *q,
518                           unsigned int len, in !! 794                               struct rq_map_data *map_data,
                                                   >> 795                               struct sg_iovec *iov, int iov_count,
                                                   >> 796                               int write_to_vm, gfp_t gfp_mask)
519 {                                                 797 {
520         unsigned long end = (uaddr + len + PAG << 
521         unsigned long start = uaddr >> PAGE_SH << 
522         struct bio_map_data *bmd;                 798         struct bio_map_data *bmd;
523         struct bio_vec *bvec;                     799         struct bio_vec *bvec;
524         struct page *page;                        800         struct page *page;
525         struct bio *bio;                          801         struct bio *bio;
526         int i, ret;                               802         int i, ret;
                                                   >> 803         int nr_pages = 0;
                                                   >> 804         unsigned int len = 0;
                                                   >> 805         unsigned int offset = map_data ? map_data->offset & ~PAGE_MASK : 0;
                                                   >> 806 
                                                   >> 807         for (i = 0; i < iov_count; i++) {
                                                   >> 808                 unsigned long uaddr;
                                                   >> 809                 unsigned long end;
                                                   >> 810                 unsigned long start;
                                                   >> 811 
                                                   >> 812                 uaddr = (unsigned long)iov[i].iov_base;
                                                   >> 813                 end = (uaddr + iov[i].iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
                                                   >> 814                 start = uaddr >> PAGE_SHIFT;
                                                   >> 815 
                                                   >> 816                 nr_pages += end - start;
                                                   >> 817                 len += iov[i].iov_len;
                                                   >> 818         }
527                                                   819 
528         bmd = bio_alloc_map_data(end - start); !! 820         if (offset)
                                                   >> 821                 nr_pages++;
                                                   >> 822 
                                                   >> 823         bmd = bio_alloc_map_data(nr_pages, iov_count, gfp_mask);
529         if (!bmd)                                 824         if (!bmd)
530                 return ERR_PTR(-ENOMEM);          825                 return ERR_PTR(-ENOMEM);
531                                                   826 
532         bmd->userptr = (void __user *) uaddr;  << 
533                                                << 
534         ret = -ENOMEM;                            827         ret = -ENOMEM;
535         bio = bio_alloc(GFP_KERNEL, end - star !! 828         bio = bio_kmalloc(gfp_mask, nr_pages);
536         if (!bio)                                 829         if (!bio)
537                 goto out_bmd;                     830                 goto out_bmd;
538                                                   831 
539         bio->bi_rw |= (!write_to_vm << BIO_RW)    832         bio->bi_rw |= (!write_to_vm << BIO_RW);
540                                                   833 
541         ret = 0;                                  834         ret = 0;
                                                   >> 835 
                                                   >> 836         if (map_data) {
                                                   >> 837                 nr_pages = 1 << map_data->page_order;
                                                   >> 838                 i = map_data->offset / PAGE_SIZE;
                                                   >> 839         }
542         while (len) {                             840         while (len) {
543                 unsigned int bytes = PAGE_SIZE    841                 unsigned int bytes = PAGE_SIZE;
544                                                   842 
                                                   >> 843                 bytes -= offset;
                                                   >> 844 
545                 if (bytes > len)                  845                 if (bytes > len)
546                         bytes = len;              846                         bytes = len;
547                                                   847 
548                 page = alloc_page(q->bounce_gf !! 848                 if (map_data) {
549                 if (!page) {                   !! 849                         if (i == map_data->nr_entries * nr_pages) {
550                         ret = -ENOMEM;         !! 850                                 ret = -ENOMEM;
551                         break;                 !! 851                                 break;
                                                   >> 852                         }
                                                   >> 853 
                                                   >> 854                         page = map_data->pages[i / nr_pages];
                                                   >> 855                         page += (i % nr_pages);
                                                   >> 856 
                                                   >> 857                         i++;
                                                   >> 858                 } else {
                                                   >> 859                         page = alloc_page(q->bounce_gfp | gfp_mask);
                                                   >> 860                         if (!page) {
                                                   >> 861                                 ret = -ENOMEM;
                                                   >> 862                                 break;
                                                   >> 863                         }
552                 }                                 864                 }
553                                                   865 
554                 if (bio_add_pc_page(q, bio, pa !! 866                 if (bio_add_pc_page(q, bio, page, bytes, offset) < bytes)
555                         break;                    867                         break;
556                                                   868 
557                 len -= bytes;                     869                 len -= bytes;
                                                   >> 870                 offset = 0;
558         }                                         871         }
559                                                   872 
560         if (ret)                                  873         if (ret)
561                 goto cleanup;                     874                 goto cleanup;
562                                                   875 
563         /*                                        876         /*
564          * success                                877          * success
565          */                                       878          */
566         if (!write_to_vm) {                    !! 879         if ((!write_to_vm && (!map_data || !map_data->null_mapped)) ||
567                 char __user *p = (char __user  !! 880             (map_data && map_data->from_user)) {
568                                                !! 881                 ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 1, 0);
569                 /*                             !! 882                 if (ret)
570                  * for a write, copy in data t !! 883                         goto cleanup;
571                  */                            << 
572                 ret = -EFAULT;                 << 
573                 bio_for_each_segment(bvec, bio << 
574                         char *addr = page_addr << 
575                                                << 
576                         if (copy_from_user(add << 
577                                 goto cleanup;  << 
578                         p += bvec->bv_len;     << 
579                 }                              << 
580         }                                         884         }
581                                                   885 
582         bio_set_map_data(bmd, bio);            !! 886         bio_set_map_data(bmd, bio, iov, iov_count, map_data ? 0 : 1);
583         return bio;                               887         return bio;
584 cleanup:                                          888 cleanup:
585         bio_for_each_segment(bvec, bio, i)     !! 889         if (!map_data)
586                 __free_page(bvec->bv_page);    !! 890                 bio_for_each_segment(bvec, bio, i)
                                                   >> 891                         __free_page(bvec->bv_page);
587                                                   892 
588         bio_put(bio);                             893         bio_put(bio);
589 out_bmd:                                          894 out_bmd:
590         bio_free_map_data(bmd);                   895         bio_free_map_data(bmd);
591         return ERR_PTR(ret);                      896         return ERR_PTR(ret);
592 }                                                 897 }
593                                                   898 
                                                   >> 899 /**
                                                   >> 900  *      bio_copy_user   -       copy user data to bio
                                                   >> 901  *      @q: destination block queue
                                                   >> 902  *      @map_data: pointer to the rq_map_data holding pages (if necessary)
                                                   >> 903  *      @uaddr: start of user address
                                                   >> 904  *      @len: length in bytes
                                                   >> 905  *      @write_to_vm: bool indicating writing to pages or not
                                                   >> 906  *      @gfp_mask: memory allocation flags
                                                   >> 907  *
                                                   >> 908  *      Prepares and returns a bio for indirect user io, bouncing data
                                                   >> 909  *      to/from kernel pages as necessary. Must be paired with
                                                   >> 910  *      call bio_uncopy_user() on io completion.
                                                   >> 911  */
                                                   >> 912 struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data,
                                                   >> 913                           unsigned long uaddr, unsigned int len,
                                                   >> 914                           int write_to_vm, gfp_t gfp_mask)
                                                   >> 915 {
                                                   >> 916         struct sg_iovec iov;
                                                   >> 917 
                                                   >> 918         iov.iov_base = (void __user *)uaddr;
                                                   >> 919         iov.iov_len = len;
                                                   >> 920 
                                                   >> 921         return bio_copy_user_iov(q, map_data, &iov, 1, write_to_vm, gfp_mask);
                                                   >> 922 }
                                                   >> 923 
594 static struct bio *__bio_map_user_iov(struct r    924 static struct bio *__bio_map_user_iov(struct request_queue *q,
595                                       struct b    925                                       struct block_device *bdev,
596                                       struct s    926                                       struct sg_iovec *iov, int iov_count,
597                                       int writ !! 927                                       int write_to_vm, gfp_t gfp_mask)
598 {                                                 928 {
599         int i, j;                                 929         int i, j;
600         int nr_pages = 0;                         930         int nr_pages = 0;
601         struct page **pages;                      931         struct page **pages;
602         struct bio *bio;                          932         struct bio *bio;
603         int cur_page = 0;                         933         int cur_page = 0;
604         int ret, offset;                          934         int ret, offset;
605                                                   935 
606         for (i = 0; i < iov_count; i++) {         936         for (i = 0; i < iov_count; i++) {
607                 unsigned long uaddr = (unsigne    937                 unsigned long uaddr = (unsigned long)iov[i].iov_base;
608                 unsigned long len = iov[i].iov    938                 unsigned long len = iov[i].iov_len;
609                 unsigned long end = (uaddr + l    939                 unsigned long end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
610                 unsigned long start = uaddr >>    940                 unsigned long start = uaddr >> PAGE_SHIFT;
611                                                   941 
612                 nr_pages += end - start;          942                 nr_pages += end - start;
613                 /*                                943                 /*
614                  * buffer must be aligned to a    944                  * buffer must be aligned to at least hardsector size for now
615                  */                               945                  */
616                 if (uaddr & queue_dma_alignmen    946                 if (uaddr & queue_dma_alignment(q))
617                         return ERR_PTR(-EINVAL    947                         return ERR_PTR(-EINVAL);
618         }                                         948         }
619                                                   949 
620         if (!nr_pages)                            950         if (!nr_pages)
621                 return ERR_PTR(-EINVAL);          951                 return ERR_PTR(-EINVAL);
622                                                   952 
623         bio = bio_alloc(GFP_KERNEL, nr_pages); !! 953         bio = bio_kmalloc(gfp_mask, nr_pages);
624         if (!bio)                                 954         if (!bio)
625                 return ERR_PTR(-ENOMEM);          955                 return ERR_PTR(-ENOMEM);
626                                                   956 
627         ret = -ENOMEM;                            957         ret = -ENOMEM;
628         pages = kcalloc(nr_pages, sizeof(struc !! 958         pages = kcalloc(nr_pages, sizeof(struct page *), gfp_mask);
629         if (!pages)                               959         if (!pages)
630                 goto out;                         960                 goto out;
631                                                   961 
632         for (i = 0; i < iov_count; i++) {         962         for (i = 0; i < iov_count; i++) {
633                 unsigned long uaddr = (unsigne    963                 unsigned long uaddr = (unsigned long)iov[i].iov_base;
634                 unsigned long len = iov[i].iov    964                 unsigned long len = iov[i].iov_len;
635                 unsigned long end = (uaddr + l    965                 unsigned long end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
636                 unsigned long start = uaddr >>    966                 unsigned long start = uaddr >> PAGE_SHIFT;
637                 const int local_nr_pages = end    967                 const int local_nr_pages = end - start;
638                 const int page_limit = cur_pag    968                 const int page_limit = cur_page + local_nr_pages;
639                                                   969                 
640                 down_read(&current->mm->mmap_s !! 970                 ret = get_user_pages_fast(uaddr, local_nr_pages,
641                 ret = get_user_pages(current,  !! 971                                 write_to_vm, &pages[cur_page]);
642                                      local_nr_ << 
643                                      write_to_ << 
644                 up_read(&current->mm->mmap_sem << 
645                                                << 
646                 if (ret < local_nr_pages) {       972                 if (ret < local_nr_pages) {
647                         ret = -EFAULT;            973                         ret = -EFAULT;
648                         goto out_unmap;           974                         goto out_unmap;
649                 }                                 975                 }
650                                                   976 
651                 offset = uaddr & ~PAGE_MASK;      977                 offset = uaddr & ~PAGE_MASK;
652                 for (j = cur_page; j < page_li    978                 for (j = cur_page; j < page_limit; j++) {
653                         unsigned int bytes = P    979                         unsigned int bytes = PAGE_SIZE - offset;
654                                                   980 
655                         if (len <= 0)             981                         if (len <= 0)
656                                 break;            982                                 break;
657                                                   983                         
658                         if (bytes > len)          984                         if (bytes > len)
659                                 bytes = len;      985                                 bytes = len;
660                                                   986 
661                         /*                        987                         /*
662                          * sorry...               988                          * sorry...
663                          */                       989                          */
664                         if (bio_add_pc_page(q,    990                         if (bio_add_pc_page(q, bio, pages[j], bytes, offset) <
665                                             by    991                                             bytes)
666                                 break;            992                                 break;
667                                                   993 
668                         len -= bytes;             994                         len -= bytes;
669                         offset = 0;               995                         offset = 0;
670                 }                                 996                 }
671                                                   997 
672                 cur_page = j;                     998                 cur_page = j;
673                 /*                                999                 /*
674                  * release the pages we didn't    1000                  * release the pages we didn't map into the bio, if any
675                  */                               1001                  */
676                 while (j < page_limit)            1002                 while (j < page_limit)
677                         page_cache_release(pag    1003                         page_cache_release(pages[j++]);
678         }                                         1004         }
679                                                   1005 
680         kfree(pages);                             1006         kfree(pages);
681                                                   1007 
682         /*                                        1008         /*
683          * set data direction, and check if ma    1009          * set data direction, and check if mapped pages need bouncing
684          */                                       1010          */
685         if (!write_to_vm)                         1011         if (!write_to_vm)
686                 bio->bi_rw |= (1 << BIO_RW);      1012                 bio->bi_rw |= (1 << BIO_RW);
687                                                   1013 
688         bio->bi_bdev = bdev;                      1014         bio->bi_bdev = bdev;
689         bio->bi_flags |= (1 << BIO_USER_MAPPED    1015         bio->bi_flags |= (1 << BIO_USER_MAPPED);
690         return bio;                               1016         return bio;
691                                                   1017 
692  out_unmap:                                       1018  out_unmap:
693         for (i = 0; i < nr_pages; i++) {          1019         for (i = 0; i < nr_pages; i++) {
694                 if(!pages[i])                     1020                 if(!pages[i])
695                         break;                    1021                         break;
696                 page_cache_release(pages[i]);     1022                 page_cache_release(pages[i]);
697         }                                         1023         }
698  out:                                             1024  out:
699         kfree(pages);                             1025         kfree(pages);
700         bio_put(bio);                             1026         bio_put(bio);
701         return ERR_PTR(ret);                      1027         return ERR_PTR(ret);
702 }                                                 1028 }
703                                                   1029 
704 /**                                               1030 /**
705  *      bio_map_user    -       map user addre    1031  *      bio_map_user    -       map user address into bio
706  *      @q: the struct request_queue for the b    1032  *      @q: the struct request_queue for the bio
707  *      @bdev: destination block device           1033  *      @bdev: destination block device
708  *      @uaddr: start of user address             1034  *      @uaddr: start of user address
709  *      @len: length in bytes                     1035  *      @len: length in bytes
710  *      @write_to_vm: bool indicating writing     1036  *      @write_to_vm: bool indicating writing to pages or not
                                                   >> 1037  *      @gfp_mask: memory allocation flags
711  *                                                1038  *
712  *      Map the user space address into a bio     1039  *      Map the user space address into a bio suitable for io to a block
713  *      device. Returns an error pointer in ca    1040  *      device. Returns an error pointer in case of error.
714  */                                               1041  */
715 struct bio *bio_map_user(struct request_queue     1042 struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev,
716                          unsigned long uaddr,  !! 1043                          unsigned long uaddr, unsigned int len, int write_to_vm,
                                                   >> 1044                          gfp_t gfp_mask)
717 {                                                 1045 {
718         struct sg_iovec iov;                      1046         struct sg_iovec iov;
719                                                   1047 
720         iov.iov_base = (void __user *)uaddr;      1048         iov.iov_base = (void __user *)uaddr;
721         iov.iov_len = len;                        1049         iov.iov_len = len;
722                                                   1050 
723         return bio_map_user_iov(q, bdev, &iov, !! 1051         return bio_map_user_iov(q, bdev, &iov, 1, write_to_vm, gfp_mask);
724 }                                                 1052 }
725                                                   1053 
726 /**                                               1054 /**
727  *      bio_map_user_iov - map user sg_iovec t    1055  *      bio_map_user_iov - map user sg_iovec table into bio
728  *      @q: the struct request_queue for the b    1056  *      @q: the struct request_queue for the bio
729  *      @bdev: destination block device           1057  *      @bdev: destination block device
730  *      @iov:   the iovec.                        1058  *      @iov:   the iovec.
731  *      @iov_count: number of elements in the     1059  *      @iov_count: number of elements in the iovec
732  *      @write_to_vm: bool indicating writing     1060  *      @write_to_vm: bool indicating writing to pages or not
                                                   >> 1061  *      @gfp_mask: memory allocation flags
733  *                                                1062  *
734  *      Map the user space address into a bio     1063  *      Map the user space address into a bio suitable for io to a block
735  *      device. Returns an error pointer in ca    1064  *      device. Returns an error pointer in case of error.
736  */                                               1065  */
737 struct bio *bio_map_user_iov(struct request_qu    1066 struct bio *bio_map_user_iov(struct request_queue *q, struct block_device *bdev,
738                              struct sg_iovec *    1067                              struct sg_iovec *iov, int iov_count,
739                              int write_to_vm)  !! 1068                              int write_to_vm, gfp_t gfp_mask)
740 {                                                 1069 {
741         struct bio *bio;                          1070         struct bio *bio;
742                                                   1071 
743         bio = __bio_map_user_iov(q, bdev, iov, !! 1072         bio = __bio_map_user_iov(q, bdev, iov, iov_count, write_to_vm,
744                                                !! 1073                                  gfp_mask);
745         if (IS_ERR(bio))                          1074         if (IS_ERR(bio))
746                 return bio;                       1075                 return bio;
747                                                   1076 
748         /*                                        1077         /*
749          * subtle -- if __bio_map_user() ended    1078          * subtle -- if __bio_map_user() ended up bouncing a bio,
750          * it would normally disappear when it    1079          * it would normally disappear when its bi_end_io is run.
751          * however, we need it for the unmap,     1080          * however, we need it for the unmap, so grab an extra
752          * reference to it                        1081          * reference to it
753          */                                       1082          */
754         bio_get(bio);                             1083         bio_get(bio);
755                                                   1084 
756         return bio;                               1085         return bio;
757 }                                                 1086 }
758                                                   1087 
759 static void __bio_unmap_user(struct bio *bio)     1088 static void __bio_unmap_user(struct bio *bio)
760 {                                                 1089 {
761         struct bio_vec *bvec;                     1090         struct bio_vec *bvec;
762         int i;                                    1091         int i;
763                                                   1092 
764         /*                                        1093         /*
765          * make sure we dirty pages we wrote t    1094          * make sure we dirty pages we wrote to
766          */                                       1095          */
767         __bio_for_each_segment(bvec, bio, i, 0    1096         __bio_for_each_segment(bvec, bio, i, 0) {
768                 if (bio_data_dir(bio) == READ)    1097                 if (bio_data_dir(bio) == READ)
769                         set_page_dirty_lock(bv    1098                         set_page_dirty_lock(bvec->bv_page);
770                                                   1099 
771                 page_cache_release(bvec->bv_pa    1100                 page_cache_release(bvec->bv_page);
772         }                                         1101         }
773                                                   1102 
774         bio_put(bio);                             1103         bio_put(bio);
775 }                                                 1104 }
776                                                   1105 
777 /**                                               1106 /**
778  *      bio_unmap_user  -       unmap a bio       1107  *      bio_unmap_user  -       unmap a bio
779  *      @bio:           the bio being unmapped    1108  *      @bio:           the bio being unmapped
780  *                                                1109  *
781  *      Unmap a bio previously mapped by bio_m    1110  *      Unmap a bio previously mapped by bio_map_user(). Must be called with
782  *      a process context.                        1111  *      a process context.
783  *                                                1112  *
784  *      bio_unmap_user() may sleep.               1113  *      bio_unmap_user() may sleep.
785  */                                               1114  */
786 void bio_unmap_user(struct bio *bio)              1115 void bio_unmap_user(struct bio *bio)
787 {                                                 1116 {
788         __bio_unmap_user(bio);                    1117         __bio_unmap_user(bio);
789         bio_put(bio);                             1118         bio_put(bio);
790 }                                                 1119 }
791                                                   1120 
792 static void bio_map_kern_endio(struct bio *bio    1121 static void bio_map_kern_endio(struct bio *bio, int err)
793 {                                                 1122 {
794         bio_put(bio);                             1123         bio_put(bio);
795 }                                                 1124 }
796                                                   1125 
797                                                   1126 
798 static struct bio *__bio_map_kern(struct reque    1127 static struct bio *__bio_map_kern(struct request_queue *q, void *data,
799                                   unsigned int    1128                                   unsigned int len, gfp_t gfp_mask)
800 {                                                 1129 {
801         unsigned long kaddr = (unsigned long)d    1130         unsigned long kaddr = (unsigned long)data;
802         unsigned long end = (kaddr + len + PAG    1131         unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
803         unsigned long start = kaddr >> PAGE_SH    1132         unsigned long start = kaddr >> PAGE_SHIFT;
804         const int nr_pages = end - start;         1133         const int nr_pages = end - start;
805         int offset, i;                            1134         int offset, i;
806         struct bio *bio;                          1135         struct bio *bio;
807                                                   1136 
808         bio = bio_alloc(gfp_mask, nr_pages);   !! 1137         bio = bio_kmalloc(gfp_mask, nr_pages);
809         if (!bio)                                 1138         if (!bio)
810                 return ERR_PTR(-ENOMEM);          1139                 return ERR_PTR(-ENOMEM);
811                                                   1140 
812         offset = offset_in_page(kaddr);           1141         offset = offset_in_page(kaddr);
813         for (i = 0; i < nr_pages; i++) {          1142         for (i = 0; i < nr_pages; i++) {
814                 unsigned int bytes = PAGE_SIZE    1143                 unsigned int bytes = PAGE_SIZE - offset;
815                                                   1144 
816                 if (len <= 0)                     1145                 if (len <= 0)
817                         break;                    1146                         break;
818                                                   1147 
819                 if (bytes > len)                  1148                 if (bytes > len)
820                         bytes = len;              1149                         bytes = len;
821                                                   1150 
822                 if (bio_add_pc_page(q, bio, vi    1151                 if (bio_add_pc_page(q, bio, virt_to_page(data), bytes,
823                                     offset) <     1152                                     offset) < bytes)
824                         break;                    1153                         break;
825                                                   1154 
826                 data += bytes;                    1155                 data += bytes;
827                 len -= bytes;                     1156                 len -= bytes;
828                 offset = 0;                       1157                 offset = 0;
829         }                                         1158         }
830                                                   1159 
831         bio->bi_end_io = bio_map_kern_endio;      1160         bio->bi_end_io = bio_map_kern_endio;
832         return bio;                               1161         return bio;
833 }                                                 1162 }
834                                                   1163 
835 /**                                               1164 /**
836  *      bio_map_kern    -       map kernel add    1165  *      bio_map_kern    -       map kernel address into bio
837  *      @q: the struct request_queue for the b    1166  *      @q: the struct request_queue for the bio
838  *      @data: pointer to buffer to map           1167  *      @data: pointer to buffer to map
839  *      @len: length in bytes                     1168  *      @len: length in bytes
840  *      @gfp_mask: allocation flags for bio al    1169  *      @gfp_mask: allocation flags for bio allocation
841  *                                                1170  *
842  *      Map the kernel address into a bio suit    1171  *      Map the kernel address into a bio suitable for io to a block
843  *      device. Returns an error pointer in ca    1172  *      device. Returns an error pointer in case of error.
844  */                                               1173  */
845 struct bio *bio_map_kern(struct request_queue     1174 struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len,
846                          gfp_t gfp_mask)          1175                          gfp_t gfp_mask)
847 {                                                 1176 {
848         struct bio *bio;                          1177         struct bio *bio;
849                                                   1178 
850         bio = __bio_map_kern(q, data, len, gfp    1179         bio = __bio_map_kern(q, data, len, gfp_mask);
851         if (IS_ERR(bio))                          1180         if (IS_ERR(bio))
852                 return bio;                       1181                 return bio;
853                                                   1182 
854         if (bio->bi_size == len)                  1183         if (bio->bi_size == len)
855                 return bio;                       1184                 return bio;
856                                                   1185 
857         /*                                        1186         /*
858          * Don't support partial mappings.        1187          * Don't support partial mappings.
859          */                                       1188          */
860         bio_put(bio);                             1189         bio_put(bio);
861         return ERR_PTR(-EINVAL);                  1190         return ERR_PTR(-EINVAL);
862 }                                                 1191 }
863                                                   1192 
                                                   >> 1193 static void bio_copy_kern_endio(struct bio *bio, int err)
                                                   >> 1194 {
                                                   >> 1195         struct bio_vec *bvec;
                                                   >> 1196         const int read = bio_data_dir(bio) == READ;
                                                   >> 1197         struct bio_map_data *bmd = bio->bi_private;
                                                   >> 1198         int i;
                                                   >> 1199         char *p = bmd->sgvecs[0].iov_base;
                                                   >> 1200 
                                                   >> 1201         __bio_for_each_segment(bvec, bio, i, 0) {
                                                   >> 1202                 char *addr = page_address(bvec->bv_page);
                                                   >> 1203                 int len = bmd->iovecs[i].bv_len;
                                                   >> 1204 
                                                   >> 1205                 if (read)
                                                   >> 1206                         memcpy(p, addr, len);
                                                   >> 1207 
                                                   >> 1208                 __free_page(bvec->bv_page);
                                                   >> 1209                 p += len;
                                                   >> 1210         }
                                                   >> 1211 
                                                   >> 1212         bio_free_map_data(bmd);
                                                   >> 1213         bio_put(bio);
                                                   >> 1214 }
                                                   >> 1215 
                                                   >> 1216 /**
                                                   >> 1217  *      bio_copy_kern   -       copy kernel address into bio
                                                   >> 1218  *      @q: the struct request_queue for the bio
                                                   >> 1219  *      @data: pointer to buffer to copy
                                                   >> 1220  *      @len: length in bytes
                                                   >> 1221  *      @gfp_mask: allocation flags for bio and page allocation
                                                   >> 1222  *      @reading: data direction is READ
                                                   >> 1223  *
                                                   >> 1224  *      copy the kernel address into a bio suitable for io to a block
                                                   >> 1225  *      device. Returns an error pointer in case of error.
                                                   >> 1226  */
                                                   >> 1227 struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len,
                                                   >> 1228                           gfp_t gfp_mask, int reading)
                                                   >> 1229 {
                                                   >> 1230         struct bio *bio;
                                                   >> 1231         struct bio_vec *bvec;
                                                   >> 1232         int i;
                                                   >> 1233 
                                                   >> 1234         bio = bio_copy_user(q, NULL, (unsigned long)data, len, 1, gfp_mask);
                                                   >> 1235         if (IS_ERR(bio))
                                                   >> 1236                 return bio;
                                                   >> 1237 
                                                   >> 1238         if (!reading) {
                                                   >> 1239                 void *p = data;
                                                   >> 1240 
                                                   >> 1241                 bio_for_each_segment(bvec, bio, i) {
                                                   >> 1242                         char *addr = page_address(bvec->bv_page);
                                                   >> 1243 
                                                   >> 1244                         memcpy(addr, p, bvec->bv_len);
                                                   >> 1245                         p += bvec->bv_len;
                                                   >> 1246                 }
                                                   >> 1247         }
                                                   >> 1248 
                                                   >> 1249         bio->bi_end_io = bio_copy_kern_endio;
                                                   >> 1250 
                                                   >> 1251         return bio;
                                                   >> 1252 }
                                                   >> 1253 
864 /*                                                1254 /*
865  * bio_set_pages_dirty() and bio_check_pages_d    1255  * bio_set_pages_dirty() and bio_check_pages_dirty() are support functions
866  * for performing direct-IO in BIOs.              1256  * for performing direct-IO in BIOs.
867  *                                                1257  *
868  * The problem is that we cannot run set_page_    1258  * The problem is that we cannot run set_page_dirty() from interrupt context
869  * because the required locks are not interrup    1259  * because the required locks are not interrupt-safe.  So what we can do is to
870  * mark the pages dirty _before_ performing IO    1260  * mark the pages dirty _before_ performing IO.  And in interrupt context,
871  * check that the pages are still dirty.   If     1261  * check that the pages are still dirty.   If so, fine.  If not, redirty them
872  * in process context.                            1262  * in process context.
873  *                                                1263  *
874  * We special-case compound pages here: normal    1264  * We special-case compound pages here: normally this means reads into hugetlb
875  * pages.  The logic in here doesn't really wo    1265  * pages.  The logic in here doesn't really work right for compound pages
876  * because the VM does not uniformly chase dow    1266  * because the VM does not uniformly chase down the head page in all cases.
877  * But dirtiness of compound pages is pretty m    1267  * But dirtiness of compound pages is pretty meaningless anyway: the VM doesn't
878  * handle them at all.  So we skip compound pa    1268  * handle them at all.  So we skip compound pages here at an early stage.
879  *                                                1269  *
880  * Note that this code is very hard to test un    1270  * Note that this code is very hard to test under normal circumstances because
881  * direct-io pins the pages with get_user_page    1271  * direct-io pins the pages with get_user_pages().  This makes
882  * is_page_cache_freeable return false, and th    1272  * is_page_cache_freeable return false, and the VM will not clean the pages.
883  * But other code (eg, pdflush) could clean th    1273  * But other code (eg, pdflush) could clean the pages if they are mapped
884  * pagecache.                                     1274  * pagecache.
885  *                                                1275  *
886  * Simply disabling the call to bio_set_pages_    1276  * Simply disabling the call to bio_set_pages_dirty() is a good way to test the
887  * deferred bio dirtying paths.                   1277  * deferred bio dirtying paths.
888  */                                               1278  */
889                                                   1279 
890 /*                                                1280 /*
891  * bio_set_pages_dirty() will mark all the bio    1281  * bio_set_pages_dirty() will mark all the bio's pages as dirty.
892  */                                               1282  */
893 void bio_set_pages_dirty(struct bio *bio)         1283 void bio_set_pages_dirty(struct bio *bio)
894 {                                                 1284 {
895         struct bio_vec *bvec = bio->bi_io_vec;    1285         struct bio_vec *bvec = bio->bi_io_vec;
896         int i;                                    1286         int i;
897                                                   1287 
898         for (i = 0; i < bio->bi_vcnt; i++) {      1288         for (i = 0; i < bio->bi_vcnt; i++) {
899                 struct page *page = bvec[i].bv    1289                 struct page *page = bvec[i].bv_page;
900                                                   1290 
901                 if (page && !PageCompound(page    1291                 if (page && !PageCompound(page))
902                         set_page_dirty_lock(pa    1292                         set_page_dirty_lock(page);
903         }                                         1293         }
904 }                                                 1294 }
905                                                   1295 
906 static void bio_release_pages(struct bio *bio)    1296 static void bio_release_pages(struct bio *bio)
907 {                                                 1297 {
908         struct bio_vec *bvec = bio->bi_io_vec;    1298         struct bio_vec *bvec = bio->bi_io_vec;
909         int i;                                    1299         int i;
910                                                   1300 
911         for (i = 0; i < bio->bi_vcnt; i++) {      1301         for (i = 0; i < bio->bi_vcnt; i++) {
912                 struct page *page = bvec[i].bv    1302                 struct page *page = bvec[i].bv_page;
913                                                   1303 
914                 if (page)                         1304                 if (page)
915                         put_page(page);           1305                         put_page(page);
916         }                                         1306         }
917 }                                                 1307 }
918                                                   1308 
919 /*                                                1309 /*
920  * bio_check_pages_dirty() will check that all    1310  * bio_check_pages_dirty() will check that all the BIO's pages are still dirty.
921  * If they are, then fine.  If, however, some     1311  * If they are, then fine.  If, however, some pages are clean then they must
922  * have been written out during the direct-IO     1312  * have been written out during the direct-IO read.  So we take another ref on
923  * the BIO and the offending pages and re-dirt    1313  * the BIO and the offending pages and re-dirty the pages in process context.
924  *                                                1314  *
925  * It is expected that bio_check_pages_dirty()    1315  * It is expected that bio_check_pages_dirty() will wholly own the BIO from
926  * here on.  It will run one page_cache_releas    1316  * here on.  It will run one page_cache_release() against each page and will
927  * run one bio_put() against the BIO.             1317  * run one bio_put() against the BIO.
928  */                                               1318  */
929                                                   1319 
930 static void bio_dirty_fn(struct work_struct *w    1320 static void bio_dirty_fn(struct work_struct *work);
931                                                   1321 
932 static DECLARE_WORK(bio_dirty_work, bio_dirty_    1322 static DECLARE_WORK(bio_dirty_work, bio_dirty_fn);
933 static DEFINE_SPINLOCK(bio_dirty_lock);           1323 static DEFINE_SPINLOCK(bio_dirty_lock);
934 static struct bio *bio_dirty_list;                1324 static struct bio *bio_dirty_list;
935                                                   1325 
936 /*                                                1326 /*
937  * This runs in process context                   1327  * This runs in process context
938  */                                               1328  */
939 static void bio_dirty_fn(struct work_struct *w    1329 static void bio_dirty_fn(struct work_struct *work)
940 {                                                 1330 {
941         unsigned long flags;                      1331         unsigned long flags;
942         struct bio *bio;                          1332         struct bio *bio;
943                                                   1333 
944         spin_lock_irqsave(&bio_dirty_lock, fla    1334         spin_lock_irqsave(&bio_dirty_lock, flags);
945         bio = bio_dirty_list;                     1335         bio = bio_dirty_list;
946         bio_dirty_list = NULL;                    1336         bio_dirty_list = NULL;
947         spin_unlock_irqrestore(&bio_dirty_lock    1337         spin_unlock_irqrestore(&bio_dirty_lock, flags);
948                                                   1338 
949         while (bio) {                             1339         while (bio) {
950                 struct bio *next = bio->bi_pri    1340                 struct bio *next = bio->bi_private;
951                                                   1341 
952                 bio_set_pages_dirty(bio);         1342                 bio_set_pages_dirty(bio);
953                 bio_release_pages(bio);           1343                 bio_release_pages(bio);
954                 bio_put(bio);                     1344                 bio_put(bio);
955                 bio = next;                       1345                 bio = next;
956         }                                         1346         }
957 }                                                 1347 }
958                                                   1348 
959 void bio_check_pages_dirty(struct bio *bio)       1349 void bio_check_pages_dirty(struct bio *bio)
960 {                                                 1350 {
961         struct bio_vec *bvec = bio->bi_io_vec;    1351         struct bio_vec *bvec = bio->bi_io_vec;
962         int nr_clean_pages = 0;                   1352         int nr_clean_pages = 0;
963         int i;                                    1353         int i;
964                                                   1354 
965         for (i = 0; i < bio->bi_vcnt; i++) {      1355         for (i = 0; i < bio->bi_vcnt; i++) {
966                 struct page *page = bvec[i].bv    1356                 struct page *page = bvec[i].bv_page;
967                                                   1357 
968                 if (PageDirty(page) || PageCom    1358                 if (PageDirty(page) || PageCompound(page)) {
969                         page_cache_release(pag    1359                         page_cache_release(page);
970                         bvec[i].bv_page = NULL    1360                         bvec[i].bv_page = NULL;
971                 } else {                          1361                 } else {
972                         nr_clean_pages++;         1362                         nr_clean_pages++;
973                 }                                 1363                 }
974         }                                         1364         }
975                                                   1365 
976         if (nr_clean_pages) {                     1366         if (nr_clean_pages) {
977                 unsigned long flags;              1367                 unsigned long flags;
978                                                   1368 
979                 spin_lock_irqsave(&bio_dirty_l    1369                 spin_lock_irqsave(&bio_dirty_lock, flags);
980                 bio->bi_private = bio_dirty_li    1370                 bio->bi_private = bio_dirty_list;
981                 bio_dirty_list = bio;             1371                 bio_dirty_list = bio;
982                 spin_unlock_irqrestore(&bio_di    1372                 spin_unlock_irqrestore(&bio_dirty_lock, flags);
983                 schedule_work(&bio_dirty_work)    1373                 schedule_work(&bio_dirty_work);
984         } else {                                  1374         } else {
985                 bio_put(bio);                     1375                 bio_put(bio);
986         }                                         1376         }
987 }                                                 1377 }
988                                                   1378 
989 /**                                               1379 /**
990  * bio_endio - end I/O on a bio                   1380  * bio_endio - end I/O on a bio
991  * @bio:        bio                               1381  * @bio:        bio
992  * @error:      error, if any                     1382  * @error:      error, if any
993  *                                                1383  *
994  * Description:                                   1384  * Description:
995  *   bio_endio() will end I/O on the whole bio    1385  *   bio_endio() will end I/O on the whole bio. bio_endio() is the
996  *   preferred way to end I/O on a bio, it tak    1386  *   preferred way to end I/O on a bio, it takes care of clearing
997  *   BIO_UPTODATE on error. @error is 0 on suc    1387  *   BIO_UPTODATE on error. @error is 0 on success, and and one of the
998  *   established -Exxxx (-EIO, for instance) e    1388  *   established -Exxxx (-EIO, for instance) error values in case
999  *   something went wrong. Noone should call b    1389  *   something went wrong. Noone should call bi_end_io() directly on a
1000  *   bio unless they own it and thus know tha    1390  *   bio unless they own it and thus know that it has an end_io
1001  *   function.                                   1391  *   function.
1002  **/                                             1392  **/
1003 void bio_endio(struct bio *bio, int error)       1393 void bio_endio(struct bio *bio, int error)
1004 {                                                1394 {
1005         if (error)                               1395         if (error)
1006                 clear_bit(BIO_UPTODATE, &bio-    1396                 clear_bit(BIO_UPTODATE, &bio->bi_flags);
1007         else if (!test_bit(BIO_UPTODATE, &bio    1397         else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
1008                 error = -EIO;                    1398                 error = -EIO;
1009                                                  1399 
1010         if (bio->bi_end_io)                      1400         if (bio->bi_end_io)
1011                 bio->bi_end_io(bio, error);      1401                 bio->bi_end_io(bio, error);
1012 }                                                1402 }
1013                                                  1403 
1014 void bio_pair_release(struct bio_pair *bp)       1404 void bio_pair_release(struct bio_pair *bp)
1015 {                                                1405 {
1016         if (atomic_dec_and_test(&bp->cnt)) {     1406         if (atomic_dec_and_test(&bp->cnt)) {
1017                 struct bio *master = bp->bio1    1407                 struct bio *master = bp->bio1.bi_private;
1018                                                  1408 
1019                 bio_endio(master, bp->error);    1409                 bio_endio(master, bp->error);
1020                 mempool_free(bp, bp->bio2.bi_    1410                 mempool_free(bp, bp->bio2.bi_private);
1021         }                                        1411         }
1022 }                                                1412 }
1023                                                  1413 
1024 static void bio_pair_end_1(struct bio *bi, in    1414 static void bio_pair_end_1(struct bio *bi, int err)
1025 {                                                1415 {
1026         struct bio_pair *bp = container_of(bi    1416         struct bio_pair *bp = container_of(bi, struct bio_pair, bio1);
1027                                                  1417 
1028         if (err)                                 1418         if (err)
1029                 bp->error = err;                 1419                 bp->error = err;
1030                                                  1420 
1031         bio_pair_release(bp);                    1421         bio_pair_release(bp);
1032 }                                                1422 }
1033                                                  1423 
1034 static void bio_pair_end_2(struct bio *bi, in    1424 static void bio_pair_end_2(struct bio *bi, int err)
1035 {                                                1425 {
1036         struct bio_pair *bp = container_of(bi    1426         struct bio_pair *bp = container_of(bi, struct bio_pair, bio2);
1037                                                  1427 
1038         if (err)                                 1428         if (err)
1039                 bp->error = err;                 1429                 bp->error = err;
1040                                                  1430 
1041         bio_pair_release(bp);                    1431         bio_pair_release(bp);
1042 }                                                1432 }
1043                                                  1433 
1044 /*                                               1434 /*
1045  * split a bio - only worry about a bio with  !! 1435  * split a bio - only worry about a bio with a single page in its iovec
1046  * in it's iovec                              << 
1047  */                                              1436  */
1048 struct bio_pair *bio_split(struct bio *bi, me !! 1437 struct bio_pair *bio_split(struct bio *bi, int first_sectors)
1049 {                                                1438 {
1050         struct bio_pair *bp = mempool_alloc(p !! 1439         struct bio_pair *bp = mempool_alloc(bio_split_pool, GFP_NOIO);
1051                                                  1440 
1052         if (!bp)                                 1441         if (!bp)
1053                 return bp;                       1442                 return bp;
1054                                                  1443 
1055         blk_add_trace_pdu_int(bdev_get_queue( !! 1444         trace_block_split(bdev_get_queue(bi->bi_bdev), bi,
1056                                 bi->bi_sector    1445                                 bi->bi_sector + first_sectors);
1057                                                  1446 
1058         BUG_ON(bi->bi_vcnt != 1);                1447         BUG_ON(bi->bi_vcnt != 1);
1059         BUG_ON(bi->bi_idx != 0);                 1448         BUG_ON(bi->bi_idx != 0);
1060         atomic_set(&bp->cnt, 3);                 1449         atomic_set(&bp->cnt, 3);
1061         bp->error = 0;                           1450         bp->error = 0;
1062         bp->bio1 = *bi;                          1451         bp->bio1 = *bi;
1063         bp->bio2 = *bi;                          1452         bp->bio2 = *bi;
1064         bp->bio2.bi_sector += first_sectors;     1453         bp->bio2.bi_sector += first_sectors;
1065         bp->bio2.bi_size -= first_sectors <<     1454         bp->bio2.bi_size -= first_sectors << 9;
1066         bp->bio1.bi_size = first_sectors << 9    1455         bp->bio1.bi_size = first_sectors << 9;
1067                                                  1456 
1068         bp->bv1 = bi->bi_io_vec[0];              1457         bp->bv1 = bi->bi_io_vec[0];
1069         bp->bv2 = bi->bi_io_vec[0];              1458         bp->bv2 = bi->bi_io_vec[0];
1070         bp->bv2.bv_offset += first_sectors <<    1459         bp->bv2.bv_offset += first_sectors << 9;
1071         bp->bv2.bv_len -= first_sectors << 9;    1460         bp->bv2.bv_len -= first_sectors << 9;
1072         bp->bv1.bv_len = first_sectors << 9;     1461         bp->bv1.bv_len = first_sectors << 9;
1073                                                  1462 
1074         bp->bio1.bi_io_vec = &bp->bv1;           1463         bp->bio1.bi_io_vec = &bp->bv1;
1075         bp->bio2.bi_io_vec = &bp->bv2;           1464         bp->bio2.bi_io_vec = &bp->bv2;
1076                                                  1465 
1077         bp->bio1.bi_max_vecs = 1;                1466         bp->bio1.bi_max_vecs = 1;
1078         bp->bio2.bi_max_vecs = 1;                1467         bp->bio2.bi_max_vecs = 1;
1079                                                  1468 
1080         bp->bio1.bi_end_io = bio_pair_end_1;     1469         bp->bio1.bi_end_io = bio_pair_end_1;
1081         bp->bio2.bi_end_io = bio_pair_end_2;     1470         bp->bio2.bi_end_io = bio_pair_end_2;
1082                                                  1471 
1083         bp->bio1.bi_private = bi;                1472         bp->bio1.bi_private = bi;
1084         bp->bio2.bi_private = pool;           !! 1473         bp->bio2.bi_private = bio_split_pool;
                                                   >> 1474 
                                                   >> 1475         if (bio_integrity(bi))
                                                   >> 1476                 bio_integrity_split(bi, bp, first_sectors);
1085                                                  1477 
1086         return bp;                               1478         return bp;
1087 }                                                1479 }
1088                                                  1480 
                                                   >> 1481 /**
                                                   >> 1482  *      bio_sector_offset - Find hardware sector offset in bio
                                                   >> 1483  *      @bio:           bio to inspect
                                                   >> 1484  *      @index:         bio_vec index
                                                   >> 1485  *      @offset:        offset in bv_page
                                                   >> 1486  *
                                                   >> 1487  *      Return the number of hardware sectors between beginning of bio
                                                   >> 1488  *      and an end point indicated by a bio_vec index and an offset
                                                   >> 1489  *      within that vector's page.
                                                   >> 1490  */
                                                   >> 1491 sector_t bio_sector_offset(struct bio *bio, unsigned short index,
                                                   >> 1492                            unsigned int offset)
                                                   >> 1493 {
                                                   >> 1494         unsigned int sector_sz;
                                                   >> 1495         struct bio_vec *bv;
                                                   >> 1496         sector_t sectors;
                                                   >> 1497         int i;
                                                   >> 1498 
                                                   >> 1499         sector_sz = queue_logical_block_size(bio->bi_bdev->bd_disk->queue);
                                                   >> 1500         sectors = 0;
                                                   >> 1501 
                                                   >> 1502         if (index >= bio->bi_idx)
                                                   >> 1503                 index = bio->bi_vcnt - 1;
                                                   >> 1504 
                                                   >> 1505         __bio_for_each_segment(bv, bio, i, 0) {
                                                   >> 1506                 if (i == index) {
                                                   >> 1507                         if (offset > bv->bv_offset)
                                                   >> 1508                                 sectors += (offset - bv->bv_offset) / sector_sz;
                                                   >> 1509                         break;
                                                   >> 1510                 }
                                                   >> 1511 
                                                   >> 1512                 sectors += bv->bv_len / sector_sz;
                                                   >> 1513         }
                                                   >> 1514 
                                                   >> 1515         return sectors;
                                                   >> 1516 }
                                                   >> 1517 EXPORT_SYMBOL(bio_sector_offset);
1089                                                  1518 
1090 /*                                               1519 /*
1091  * create memory pools for biovec's in a bio_    1520  * create memory pools for biovec's in a bio_set.
1092  * use the global biovec slabs created for ge    1521  * use the global biovec slabs created for general use.
1093  */                                              1522  */
1094 static int biovec_create_pools(struct bio_set    1523 static int biovec_create_pools(struct bio_set *bs, int pool_entries)
1095 {                                                1524 {
1096         int i;                                !! 1525         struct biovec_slab *bp = bvec_slabs + BIOVEC_MAX_IDX;
1097                                                  1526 
1098         for (i = 0; i < BIOVEC_NR_POOLS; i++) !! 1527         bs->bvec_pool = mempool_create_slab_pool(pool_entries, bp->slab);
1099                 struct biovec_slab *bp = bvec !! 1528         if (!bs->bvec_pool)
1100                 mempool_t **bvp = bs->bvec_po !! 1529                 return -ENOMEM;
1101                                                  1530 
1102                 *bvp = mempool_create_slab_po << 
1103                 if (!*bvp)                    << 
1104                         return -ENOMEM;       << 
1105         }                                     << 
1106         return 0;                                1531         return 0;
1107 }                                                1532 }
1108                                                  1533 
1109 static void biovec_free_pools(struct bio_set     1534 static void biovec_free_pools(struct bio_set *bs)
1110 {                                                1535 {
1111         int i;                                !! 1536         mempool_destroy(bs->bvec_pool);
1112                                               << 
1113         for (i = 0; i < BIOVEC_NR_POOLS; i++) << 
1114                 mempool_t *bvp = bs->bvec_poo << 
1115                                               << 
1116                 if (bvp)                      << 
1117                         mempool_destroy(bvp); << 
1118         }                                     << 
1119                                               << 
1120 }                                                1537 }
1121                                                  1538 
1122 void bioset_free(struct bio_set *bs)             1539 void bioset_free(struct bio_set *bs)
1123 {                                                1540 {
1124         if (bs->bio_pool)                        1541         if (bs->bio_pool)
1125                 mempool_destroy(bs->bio_pool)    1542                 mempool_destroy(bs->bio_pool);
1126                                                  1543 
                                                   >> 1544         bioset_integrity_free(bs);
1127         biovec_free_pools(bs);                   1545         biovec_free_pools(bs);
                                                   >> 1546         bio_put_slab(bs);
1128                                                  1547 
1129         kfree(bs);                               1548         kfree(bs);
1130 }                                                1549 }
1131                                                  1550 
1132 struct bio_set *bioset_create(int bio_pool_si !! 1551 /**
                                                   >> 1552  * bioset_create  - Create a bio_set
                                                   >> 1553  * @pool_size:  Number of bio and bio_vecs to cache in the mempool
                                                   >> 1554  * @front_pad:  Number of bytes to allocate in front of the returned bio
                                                   >> 1555  *
                                                   >> 1556  * Description:
                                                   >> 1557  *    Set up a bio_set to be used with @bio_alloc_bioset. Allows the caller
                                                   >> 1558  *    to ask for a number of bytes to be allocated in front of the bio.
                                                   >> 1559  *    Front pad allocation is useful for embedding the bio inside
                                                   >> 1560  *    another structure, to avoid allocating extra data to go with the bio.
                                                   >> 1561  *    Note that the bio must be embedded at the END of that structure always,
                                                   >> 1562  *    or things will break badly.
                                                   >> 1563  */
                                                   >> 1564 struct bio_set *bioset_create(unsigned int pool_size, unsigned int front_pad)
1133 {                                                1565 {
1134         struct bio_set *bs = kzalloc(sizeof(* !! 1566         unsigned int back_pad = BIO_INLINE_VECS * sizeof(struct bio_vec);
                                                   >> 1567         struct bio_set *bs;
1135                                                  1568 
                                                   >> 1569         bs = kzalloc(sizeof(*bs), GFP_KERNEL);
1136         if (!bs)                                 1570         if (!bs)
1137                 return NULL;                     1571                 return NULL;
1138                                                  1572 
1139         bs->bio_pool = mempool_create_slab_po !! 1573         bs->front_pad = front_pad;
                                                   >> 1574 
                                                   >> 1575         bs->bio_slab = bio_find_or_create_slab(front_pad + back_pad);
                                                   >> 1576         if (!bs->bio_slab) {
                                                   >> 1577                 kfree(bs);
                                                   >> 1578                 return NULL;
                                                   >> 1579         }
                                                   >> 1580 
                                                   >> 1581         bs->bio_pool = mempool_create_slab_pool(pool_size, bs->bio_slab);
1140         if (!bs->bio_pool)                       1582         if (!bs->bio_pool)
1141                 goto bad;                        1583                 goto bad;
1142                                                  1584 
1143         if (!biovec_create_pools(bs, bvec_poo !! 1585         if (bioset_integrity_create(bs, pool_size))
                                                   >> 1586                 goto bad;
                                                   >> 1587 
                                                   >> 1588         if (!biovec_create_pools(bs, pool_size))
1144                 return bs;                       1589                 return bs;
1145                                                  1590 
1146 bad:                                             1591 bad:
1147         bioset_free(bs);                         1592         bioset_free(bs);
1148         return NULL;                             1593         return NULL;
1149 }                                                1594 }
1150                                                  1595 
1151 static void __init biovec_init_slabs(void)       1596 static void __init biovec_init_slabs(void)
1152 {                                                1597 {
1153         int i;                                   1598         int i;
1154                                                  1599 
1155         for (i = 0; i < BIOVEC_NR_POOLS; i++)    1600         for (i = 0; i < BIOVEC_NR_POOLS; i++) {
1156                 int size;                        1601                 int size;
1157                 struct biovec_slab *bvs = bve    1602                 struct biovec_slab *bvs = bvec_slabs + i;
1158                                                  1603 
                                                   >> 1604 #ifndef CONFIG_BLK_DEV_INTEGRITY
                                                   >> 1605                 if (bvs->nr_vecs <= BIO_INLINE_VECS) {
                                                   >> 1606                         bvs->slab = NULL;
                                                   >> 1607                         continue;
                                                   >> 1608                 }
                                                   >> 1609 #endif
                                                   >> 1610 
1159                 size = bvs->nr_vecs * sizeof(    1611                 size = bvs->nr_vecs * sizeof(struct bio_vec);
1160                 bvs->slab = kmem_cache_create    1612                 bvs->slab = kmem_cache_create(bvs->name, size, 0,
1161                                 SLAB_HWCACHE_    1613                                 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
1162         }                                        1614         }
1163 }                                                1615 }
1164                                                  1616 
1165 static int __init init_bio(void)                 1617 static int __init init_bio(void)
1166 {                                                1618 {
1167         bio_slab = KMEM_CACHE(bio, SLAB_HWCAC !! 1619         bio_slab_max = 2;
                                                   >> 1620         bio_slab_nr = 0;
                                                   >> 1621         bio_slabs = kzalloc(bio_slab_max * sizeof(struct bio_slab), GFP_KERNEL);
                                                   >> 1622         if (!bio_slabs)
                                                   >> 1623                 panic("bio: can't allocate bios\n");
1168                                                  1624 
                                                   >> 1625         bio_integrity_init();
1169         biovec_init_slabs();                     1626         biovec_init_slabs();
1170                                                  1627 
1171         fs_bio_set = bioset_create(BIO_POOL_S !! 1628         fs_bio_set = bioset_create(BIO_POOL_SIZE, 0);
1172         if (!fs_bio_set)                         1629         if (!fs_bio_set)
1173                 panic("bio: can't allocate bi    1630                 panic("bio: can't allocate bios\n");
1174                                                  1631 
1175         bio_split_pool = mempool_create_kmall    1632         bio_split_pool = mempool_create_kmalloc_pool(BIO_SPLIT_ENTRIES,
1176                                                  1633                                                      sizeof(struct bio_pair));
1177         if (!bio_split_pool)                     1634         if (!bio_split_pool)
1178                 panic("bio: can't create spli    1635                 panic("bio: can't create split pool\n");
1179                                                  1636 
1180         return 0;                                1637         return 0;
1181 }                                                1638 }
1182                                                  1639 
1183 subsys_initcall(init_bio);                       1640 subsys_initcall(init_bio);
1184                                                  1641 
1185 EXPORT_SYMBOL(bio_alloc);                        1642 EXPORT_SYMBOL(bio_alloc);
                                                   >> 1643 EXPORT_SYMBOL(bio_kmalloc);
1186 EXPORT_SYMBOL(bio_put);                          1644 EXPORT_SYMBOL(bio_put);
1187 EXPORT_SYMBOL(bio_free);                         1645 EXPORT_SYMBOL(bio_free);
1188 EXPORT_SYMBOL(bio_endio);                        1646 EXPORT_SYMBOL(bio_endio);
1189 EXPORT_SYMBOL(bio_init);                         1647 EXPORT_SYMBOL(bio_init);
1190 EXPORT_SYMBOL(__bio_clone);                      1648 EXPORT_SYMBOL(__bio_clone);
1191 EXPORT_SYMBOL(bio_clone);                        1649 EXPORT_SYMBOL(bio_clone);
1192 EXPORT_SYMBOL(bio_phys_segments);                1650 EXPORT_SYMBOL(bio_phys_segments);
1193 EXPORT_SYMBOL(bio_hw_segments);               << 
1194 EXPORT_SYMBOL(bio_add_page);                     1651 EXPORT_SYMBOL(bio_add_page);
1195 EXPORT_SYMBOL(bio_add_pc_page);                  1652 EXPORT_SYMBOL(bio_add_pc_page);
1196 EXPORT_SYMBOL(bio_get_nr_vecs);                  1653 EXPORT_SYMBOL(bio_get_nr_vecs);
1197 EXPORT_SYMBOL(bio_map_user);                     1654 EXPORT_SYMBOL(bio_map_user);
1198 EXPORT_SYMBOL(bio_unmap_user);                   1655 EXPORT_SYMBOL(bio_unmap_user);
1199 EXPORT_SYMBOL(bio_map_kern);                     1656 EXPORT_SYMBOL(bio_map_kern);
                                                   >> 1657 EXPORT_SYMBOL(bio_copy_kern);
1200 EXPORT_SYMBOL(bio_pair_release);                 1658 EXPORT_SYMBOL(bio_pair_release);
1201 EXPORT_SYMBOL(bio_split);                        1659 EXPORT_SYMBOL(bio_split);
1202 EXPORT_SYMBOL(bio_split_pool);                << 
1203 EXPORT_SYMBOL(bio_copy_user);                    1660 EXPORT_SYMBOL(bio_copy_user);
1204 EXPORT_SYMBOL(bio_uncopy_user);                  1661 EXPORT_SYMBOL(bio_uncopy_user);
1205 EXPORT_SYMBOL(bioset_create);                    1662 EXPORT_SYMBOL(bioset_create);
1206 EXPORT_SYMBOL(bioset_free);                      1663 EXPORT_SYMBOL(bioset_free);
1207 EXPORT_SYMBOL(bio_alloc_bioset);                 1664 EXPORT_SYMBOL(bio_alloc_bioset);
1208                                                  1665 
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