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

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Differences between /linux/include/linux/bio.h (Version 2.6.25) and /linux/include/linux/bio.h (Version 2.6.31.13)


  1 /*                                                  1 /*
  2  * 2.5 block I/O model                              2  * 2.5 block I/O model
  3  *                                                  3  *
  4  * Copyright (C) 2001 Jens Axboe <axboe@suse.d      4  * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
  5  *                                                  5  *
  6  * This program is free software; you can redi      6  * This program is free software; you can redistribute it and/or modify
  7  * it under the terms of the GNU General Publi      7  * it under the terms of the GNU General Public License version 2 as
  8  * published by the Free Software Foundation.       8  * published by the Free Software Foundation.
  9  *                                                  9  *
 10  * This program is distributed in the hope tha     10  * This program is distributed in the hope that it will be useful,
 11  * but WITHOUT ANY WARRANTY; without even the      11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 12                                                    12 
 13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR     13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14  * GNU General Public License for more details     14  * GNU General Public License for more details.
 15  *                                                 15  *
 16  * You should have received a copy of the GNU      16  * You should have received a copy of the GNU General Public Licens
 17  * along with this program; if not, write to t     17  * along with this program; if not, write to the Free Software
 18  * Foundation, Inc., 59 Temple Place, Suite 33     18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
 19  */                                                19  */
 20 #ifndef __LINUX_BIO_H                              20 #ifndef __LINUX_BIO_H
 21 #define __LINUX_BIO_H                              21 #define __LINUX_BIO_H
 22                                                    22 
 23 #include <linux/highmem.h>                         23 #include <linux/highmem.h>
 24 #include <linux/mempool.h>                         24 #include <linux/mempool.h>
 25 #include <linux/ioprio.h>                          25 #include <linux/ioprio.h>
 26                                                    26 
 27 #ifdef CONFIG_BLOCK                                27 #ifdef CONFIG_BLOCK
 28                                                    28 
 29 /* Platforms may set this to teach the BIO lay << 
 30 #include <asm/io.h>                                29 #include <asm/io.h>
 31                                                    30 
 32 #if defined(BIO_VMERGE_MAX_SIZE) && defined(BI << 
 33 #define BIOVEC_VIRT_START_SIZE(x) (bvec_to_phy << 
 34 #define BIOVEC_VIRT_OVERSIZE(x) ((x) > BIO_VME << 
 35 #else                                          << 
 36 #define BIOVEC_VIRT_START_SIZE(x)       0      << 
 37 #define BIOVEC_VIRT_OVERSIZE(x)         0      << 
 38 #endif                                         << 
 39                                                << 
 40 #ifndef BIO_VMERGE_BOUNDARY                    << 
 41 #define BIO_VMERGE_BOUNDARY     0              << 
 42 #endif                                         << 
 43                                                << 
 44 #define BIO_DEBUG                                  31 #define BIO_DEBUG
 45                                                    32 
 46 #ifdef BIO_DEBUG                                   33 #ifdef BIO_DEBUG
 47 #define BIO_BUG_ON      BUG_ON                     34 #define BIO_BUG_ON      BUG_ON
 48 #else                                              35 #else
 49 #define BIO_BUG_ON                                 36 #define BIO_BUG_ON
 50 #endif                                             37 #endif
 51                                                    38 
 52 #define BIO_MAX_PAGES           256                39 #define BIO_MAX_PAGES           256
 53 #define BIO_MAX_SIZE            (BIO_MAX_PAGES     40 #define BIO_MAX_SIZE            (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
 54 #define BIO_MAX_SECTORS         (BIO_MAX_SIZE      41 #define BIO_MAX_SECTORS         (BIO_MAX_SIZE >> 9)
 55                                                    42 
 56 /*                                                 43 /*
 57  * was unsigned short, but we might as well be     44  * was unsigned short, but we might as well be ready for > 64kB I/O pages
 58  */                                                45  */
 59 struct bio_vec {                                   46 struct bio_vec {
 60         struct page     *bv_page;                  47         struct page     *bv_page;
 61         unsigned int    bv_len;                    48         unsigned int    bv_len;
 62         unsigned int    bv_offset;                 49         unsigned int    bv_offset;
 63 };                                                 50 };
 64                                                    51 
 65 struct bio_set;                                    52 struct bio_set;
 66 struct bio;                                        53 struct bio;
                                                   >>  54 struct bio_integrity_payload;
 67 typedef void (bio_end_io_t) (struct bio *, int     55 typedef void (bio_end_io_t) (struct bio *, int);
 68 typedef void (bio_destructor_t) (struct bio *)     56 typedef void (bio_destructor_t) (struct bio *);
 69                                                    57 
 70 /*                                                 58 /*
 71  * main unit of I/O for the block layer and lo     59  * main unit of I/O for the block layer and lower layers (ie drivers and
 72  * stacking drivers)                               60  * stacking drivers)
 73  */                                                61  */
 74 struct bio {                                       62 struct bio {
 75         sector_t                bi_sector;         63         sector_t                bi_sector;      /* device address in 512 byte
 76                                                    64                                                    sectors */
 77         struct bio              *bi_next;          65         struct bio              *bi_next;       /* request queue link */
 78         struct block_device     *bi_bdev;          66         struct block_device     *bi_bdev;
 79         unsigned long           bi_flags;          67         unsigned long           bi_flags;       /* status, command, etc */
 80         unsigned long           bi_rw;             68         unsigned long           bi_rw;          /* bottom bits READ/WRITE,
 81                                                    69                                                  * top bits priority
 82                                                    70                                                  */
 83                                                    71 
 84         unsigned short          bi_vcnt;           72         unsigned short          bi_vcnt;        /* how many bio_vec's */
 85         unsigned short          bi_idx;            73         unsigned short          bi_idx;         /* current index into bvl_vec */
 86                                                    74 
 87         /* Number of segments in this BIO afte     75         /* Number of segments in this BIO after
 88          * physical address coalescing is perf     76          * physical address coalescing is performed.
 89          */                                        77          */
 90         unsigned short          bi_phys_segmen !!  78         unsigned int            bi_phys_segments;
 91                                                << 
 92         /* Number of segments after physical a << 
 93          * hardware coalescing is performed.   << 
 94          */                                    << 
 95         unsigned short          bi_hw_segments << 
 96                                                    79 
 97         unsigned int            bi_size;           80         unsigned int            bi_size;        /* residual I/O count */
 98                                                    81 
 99         /*                                         82         /*
100          * To keep track of the max hw size, w !!  83          * To keep track of the max segment size, we account for the
101          * sizes of the first and last virtual !!  84          * sizes of the first and last mergeable segments in this bio.
102          * in this bio                         << 
103          */                                        85          */
104         unsigned int            bi_hw_front_si !!  86         unsigned int            bi_seg_front_size;
105         unsigned int            bi_hw_back_siz !!  87         unsigned int            bi_seg_back_size;
106                                                    88 
107         unsigned int            bi_max_vecs;       89         unsigned int            bi_max_vecs;    /* max bvl_vecs we can hold */
108                                                    90 
                                                   >>  91         unsigned int            bi_comp_cpu;    /* completion CPU */
                                                   >>  92 
                                                   >>  93         atomic_t                bi_cnt;         /* pin count */
                                                   >>  94 
109         struct bio_vec          *bi_io_vec;        95         struct bio_vec          *bi_io_vec;     /* the actual vec list */
110                                                    96 
111         bio_end_io_t            *bi_end_io;        97         bio_end_io_t            *bi_end_io;
112         atomic_t                bi_cnt;        << 
113                                                    98 
114         void                    *bi_private;       99         void                    *bi_private;
                                                   >> 100 #if defined(CONFIG_BLK_DEV_INTEGRITY)
                                                   >> 101         struct bio_integrity_payload *bi_integrity;  /* data integrity */
                                                   >> 102 #endif
115                                                   103 
116         bio_destructor_t        *bi_destructor    104         bio_destructor_t        *bi_destructor; /* destructor */
                                                   >> 105 
                                                   >> 106         /*
                                                   >> 107          * We can inline a number of vecs at the end of the bio, to avoid
                                                   >> 108          * double allocations for a small number of bio_vecs. This member
                                                   >> 109          * MUST obviously be kept at the very end of the bio.
                                                   >> 110          */
                                                   >> 111         struct bio_vec          bi_inline_vecs[0];
117 };                                                112 };
118                                                   113 
119 /*                                                114 /*
120  * bio flags                                      115  * bio flags
121  */                                               116  */
122 #define BIO_UPTODATE    0       /* ok after I/    117 #define BIO_UPTODATE    0       /* ok after I/O completion */
123 #define BIO_RW_BLOCK    1       /* RW_AHEAD se    118 #define BIO_RW_BLOCK    1       /* RW_AHEAD set, and read/write would block */
124 #define BIO_EOF         2       /* out-out-bou    119 #define BIO_EOF         2       /* out-out-bounds error */
125 #define BIO_SEG_VALID   3       /* nr_hw_seg v !! 120 #define BIO_SEG_VALID   3       /* bi_phys_segments valid */
126 #define BIO_CLONED      4       /* doesn't own    121 #define BIO_CLONED      4       /* doesn't own data */
127 #define BIO_BOUNCED     5       /* bio is a bo    122 #define BIO_BOUNCED     5       /* bio is a bounce bio */
128 #define BIO_USER_MAPPED 6       /* contains us    123 #define BIO_USER_MAPPED 6       /* contains user pages */
129 #define BIO_EOPNOTSUPP  7       /* not support    124 #define BIO_EOPNOTSUPP  7       /* not supported */
                                                   >> 125 #define BIO_CPU_AFFINE  8       /* complete bio on same CPU as submitted */
                                                   >> 126 #define BIO_NULL_MAPPED 9       /* contains invalid user pages */
                                                   >> 127 #define BIO_FS_INTEGRITY 10     /* fs owns integrity data, not block layer */
                                                   >> 128 #define BIO_QUIET       11      /* Make BIO Quiet */
130 #define bio_flagged(bio, flag)  ((bio)->bi_fla    129 #define bio_flagged(bio, flag)  ((bio)->bi_flags & (1 << (flag)))
131                                                   130 
132 /*                                                131 /*
133  * top 4 bits of bio flags indicate the pool t    132  * top 4 bits of bio flags indicate the pool this bio came from
134  */                                               133  */
135 #define BIO_POOL_BITS           (4)               134 #define BIO_POOL_BITS           (4)
                                                   >> 135 #define BIO_POOL_NONE           ((1UL << BIO_POOL_BITS) - 1)
136 #define BIO_POOL_OFFSET         (BITS_PER_LONG    136 #define BIO_POOL_OFFSET         (BITS_PER_LONG - BIO_POOL_BITS)
137 #define BIO_POOL_MASK           (1UL << BIO_PO    137 #define BIO_POOL_MASK           (1UL << BIO_POOL_OFFSET)
138 #define BIO_POOL_IDX(bio)       ((bio)->bi_fla    138 #define BIO_POOL_IDX(bio)       ((bio)->bi_flags >> BIO_POOL_OFFSET)    
139                                                   139 
140 /*                                                140 /*
141  * bio bi_rw flags                                141  * bio bi_rw flags
142  *                                                142  *
143  * bit 0 -- read (not set) or write (set)      !! 143  * bit 0 -- data direction
                                                   >> 144  *      If not set, bio is a read from device. If set, it's a write to device.
144  * bit 1 -- rw-ahead when set                     145  * bit 1 -- rw-ahead when set
145  * bit 2 -- barrier                               146  * bit 2 -- barrier
146  * bit 3 -- fail fast, don't want low level dr !! 147  *      Insert a serialization point in the IO queue, forcing previously
147  * bit 4 -- synchronous I/O hint: the block la !! 148  *      submitted IO to be completed before this one is issued.
                                                   >> 149  * bit 3 -- synchronous I/O hint.
                                                   >> 150  * bit 4 -- Unplug the device immediately after submitting this bio.
                                                   >> 151  * bit 5 -- metadata request
                                                   >> 152  *      Used for tracing to differentiate metadata and data IO. May also
                                                   >> 153  *      get some preferential treatment in the IO scheduler
                                                   >> 154  * bit 6 -- discard sectors
                                                   >> 155  *      Informs the lower level device that this range of sectors is no longer
                                                   >> 156  *      used by the file system and may thus be freed by the device. Used
                                                   >> 157  *      for flash based storage.
                                                   >> 158  * bit 7 -- fail fast device errors
                                                   >> 159  * bit 8 -- fail fast transport errors
                                                   >> 160  * bit 9 -- fail fast driver errors
                                                   >> 161  *      Don't want driver retries for any fast fail whatever the reason.
                                                   >> 162  * bit 10 -- Tell the IO scheduler not to wait for more requests after this
                                                   >> 163         one has been submitted, even if it is a SYNC request.
148  */                                               164  */
149 #define BIO_RW          0                      !! 165 #define BIO_RW          0       /* Must match RW in req flags (blkdev.h) */
150 #define BIO_RW_AHEAD    1                      !! 166 #define BIO_RW_AHEAD    1       /* Must match FAILFAST in req flags */
151 #define BIO_RW_BARRIER  2                         167 #define BIO_RW_BARRIER  2
152 #define BIO_RW_FAILFAST 3                      !! 168 #define BIO_RW_SYNCIO   3
153 #define BIO_RW_SYNC     4                      !! 169 #define BIO_RW_UNPLUG   4
154 #define BIO_RW_META     5                         170 #define BIO_RW_META     5
                                                   >> 171 #define BIO_RW_DISCARD  6
                                                   >> 172 #define BIO_RW_FAILFAST_DEV             7
                                                   >> 173 #define BIO_RW_FAILFAST_TRANSPORT       8
                                                   >> 174 #define BIO_RW_FAILFAST_DRIVER          9
                                                   >> 175 #define BIO_RW_NOIDLE   10
                                                   >> 176 
                                                   >> 177 #define bio_rw_flagged(bio, flag)       ((bio)->bi_rw & (1 << (flag)))
                                                   >> 178 
                                                   >> 179 /*
                                                   >> 180  * Old defines, these should eventually be replaced by direct usage of
                                                   >> 181  * bio_rw_flagged()
                                                   >> 182  */
                                                   >> 183 #define bio_barrier(bio)        bio_rw_flagged(bio, BIO_RW_BARRIER)
                                                   >> 184 #define bio_sync(bio)           bio_rw_flagged(bio, BIO_RW_SYNCIO)
                                                   >> 185 #define bio_unplug(bio)         bio_rw_flagged(bio, BIO_RW_UNPLUG)
                                                   >> 186 #define bio_failfast_dev(bio)   bio_rw_flagged(bio, BIO_RW_FAILFAST_DEV)
                                                   >> 187 #define bio_failfast_transport(bio)     \
                                                   >> 188                 bio_rw_flagged(bio, BIO_RW_FAILFAST_TRANSPORT)
                                                   >> 189 #define bio_failfast_driver(bio)        \
                                                   >> 190                 bio_rw_flagged(bio, BIO_RW_FAILFAST_DRIVER)
                                                   >> 191 #define bio_rw_ahead(bio)       bio_rw_flagged(bio, BIO_RW_AHEAD)
                                                   >> 192 #define bio_rw_meta(bio)        bio_rw_flagged(bio, BIO_RW_META)
                                                   >> 193 #define bio_discard(bio)        bio_rw_flagged(bio, BIO_RW_DISCARD)
                                                   >> 194 #define bio_noidle(bio)         bio_rw_flagged(bio, BIO_RW_NOIDLE)
155                                                   195 
156 /*                                                196 /*
157  * upper 16 bits of bi_rw define the io priori    197  * upper 16 bits of bi_rw define the io priority of this bio
158  */                                               198  */
159 #define BIO_PRIO_SHIFT  (8 * sizeof(unsigned l    199 #define BIO_PRIO_SHIFT  (8 * sizeof(unsigned long) - IOPRIO_BITS)
160 #define bio_prio(bio)   ((bio)->bi_rw >> BIO_P    200 #define bio_prio(bio)   ((bio)->bi_rw >> BIO_PRIO_SHIFT)
161 #define bio_prio_valid(bio)     ioprio_valid(b    201 #define bio_prio_valid(bio)     ioprio_valid(bio_prio(bio))
162                                                   202 
163 #define bio_set_prio(bio, prio)         do {      203 #define bio_set_prio(bio, prio)         do {                    \
164         WARN_ON(prio >= (1 << IOPRIO_BITS));      204         WARN_ON(prio >= (1 << IOPRIO_BITS));                    \
165         (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIF    205         (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1);          \
166         (bio)->bi_rw |= ((unsigned long) (prio    206         (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT);     \
167 } while (0)                                       207 } while (0)
168                                                   208 
169 /*                                                209 /*
170  * various member access, note that bio_data s    210  * various member access, note that bio_data should of course not be used
171  * on highmem page vectors                        211  * on highmem page vectors
172  */                                               212  */
173 #define bio_iovec_idx(bio, idx) (&((bio)->bi_i    213 #define bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)]))
174 #define bio_iovec(bio)          bio_iovec_idx(    214 #define bio_iovec(bio)          bio_iovec_idx((bio), (bio)->bi_idx)
175 #define bio_page(bio)           bio_iovec((bio    215 #define bio_page(bio)           bio_iovec((bio))->bv_page
176 #define bio_offset(bio)         bio_iovec((bio    216 #define bio_offset(bio)         bio_iovec((bio))->bv_offset
177 #define bio_segments(bio)       ((bio)->bi_vcn    217 #define bio_segments(bio)       ((bio)->bi_vcnt - (bio)->bi_idx)
178 #define bio_sectors(bio)        ((bio)->bi_siz    218 #define bio_sectors(bio)        ((bio)->bi_size >> 9)
179 #define bio_barrier(bio)        ((bio)->bi_rw  !! 219 #define bio_empty_barrier(bio)  (bio_barrier(bio) && !bio_has_data(bio) && !bio_discard(bio))
180 #define bio_sync(bio)           ((bio)->bi_rw  << 
181 #define bio_failfast(bio)       ((bio)->bi_rw  << 
182 #define bio_rw_ahead(bio)       ((bio)->bi_rw  << 
183 #define bio_rw_meta(bio)        ((bio)->bi_rw  << 
184 #define bio_empty_barrier(bio)  (bio_barrier(b << 
185                                                   220 
186 static inline unsigned int bio_cur_sectors(str !! 221 static inline unsigned int bio_cur_bytes(struct bio *bio)
187 {                                                 222 {
188         if (bio->bi_vcnt)                         223         if (bio->bi_vcnt)
189                 return bio_iovec(bio)->bv_len  !! 224                 return bio_iovec(bio)->bv_len;
190                                                !! 225         else /* dataless requests such as discard */
191         return 0;                              !! 226                 return bio->bi_size;
192 }                                                 227 }
193                                                   228 
194 static inline void *bio_data(struct bio *bio)     229 static inline void *bio_data(struct bio *bio)
195 {                                                 230 {
196         if (bio->bi_vcnt)                         231         if (bio->bi_vcnt)
197                 return page_address(bio_page(b    232                 return page_address(bio_page(bio)) + bio_offset(bio);
198                                                   233 
199         return NULL;                              234         return NULL;
200 }                                                 235 }
201                                                   236 
                                                   >> 237 static inline int bio_has_allocated_vec(struct bio *bio)
                                                   >> 238 {
                                                   >> 239         return bio->bi_io_vec && bio->bi_io_vec != bio->bi_inline_vecs;
                                                   >> 240 }
                                                   >> 241 
202 /*                                                242 /*
203  * will die                                       243  * will die
204  */                                               244  */
205 #define bio_to_phys(bio)        (page_to_phys(    245 #define bio_to_phys(bio)        (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
206 #define bvec_to_phys(bv)        (page_to_phys(    246 #define bvec_to_phys(bv)        (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
207                                                   247 
208 /*                                                248 /*
209  * queues that have highmem support enabled ma    249  * queues that have highmem support enabled may still need to revert to
210  * PIO transfers occasionally and thus map hig    250  * PIO transfers occasionally and thus map high pages temporarily. For
211  * permanent PIO fall back, user is probably b    251  * permanent PIO fall back, user is probably better off disabling highmem
212  * I/O completely on that queue (see ide-dma f    252  * I/O completely on that queue (see ide-dma for example)
213  */                                               253  */
214 #define __bio_kmap_atomic(bio, idx, kmtype)       254 #define __bio_kmap_atomic(bio, idx, kmtype)                             \
215         (kmap_atomic(bio_iovec_idx((bio), (idx    255         (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page, kmtype) +    \
216                 bio_iovec_idx((bio), (idx))->b    256                 bio_iovec_idx((bio), (idx))->bv_offset)
217                                                   257 
218 #define __bio_kunmap_atomic(addr, kmtype) kunm    258 #define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr, kmtype)
219                                                   259 
220 /*                                                260 /*
221  * merge helpers etc                              261  * merge helpers etc
222  */                                               262  */
223                                                   263 
224 #define __BVEC_END(bio)         bio_iovec_idx(    264 #define __BVEC_END(bio)         bio_iovec_idx((bio), (bio)->bi_vcnt - 1)
225 #define __BVEC_START(bio)       bio_iovec_idx(    265 #define __BVEC_START(bio)       bio_iovec_idx((bio), (bio)->bi_idx)
226                                                   266 
                                                   >> 267 /* Default implementation of BIOVEC_PHYS_MERGEABLE */
                                                   >> 268 #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2)     \
                                                   >> 269         ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
                                                   >> 270 
227 /*                                                271 /*
228  * allow arch override, for eg virtualized arc    272  * allow arch override, for eg virtualized architectures (put in asm/io.h)
229  */                                               273  */
230 #ifndef BIOVEC_PHYS_MERGEABLE                     274 #ifndef BIOVEC_PHYS_MERGEABLE
231 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)         275 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)       \
232         ((bvec_to_phys((vec1)) + (vec1)->bv_le !! 276         __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
233 #endif                                            277 #endif
234                                                   278 
235 #define BIOVEC_VIRT_MERGEABLE(vec1, vec2)      << 
236         ((((bvec_to_phys((vec1)) + (vec1)->bv_ << 
237 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask)    279 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
238         (((addr1) | (mask)) == (((addr2) - 1)     280         (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
239 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \          281 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
240         __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), !! 282         __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
241 #define BIO_SEG_BOUNDARY(q, b1, b2) \             283 #define BIO_SEG_BOUNDARY(q, b1, b2) \
242         BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b    284         BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
243                                                   285 
244 #define bio_io_error(bio) bio_endio((bio), -EI    286 #define bio_io_error(bio) bio_endio((bio), -EIO)
245                                                   287 
246 /*                                                288 /*
247  * drivers should not use the __ version unles    289  * drivers should not use the __ version unless they _really_ want to
248  * run through the entire bio and not just pen    290  * run through the entire bio and not just pending pieces
249  */                                               291  */
250 #define __bio_for_each_segment(bvl, bio, i, st    292 #define __bio_for_each_segment(bvl, bio, i, start_idx)                  \
251         for (bvl = bio_iovec_idx((bio), (start    293         for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx);  \
252              i < (bio)->bi_vcnt;                  294              i < (bio)->bi_vcnt;                                        \
253              bvl++, i++)                          295              bvl++, i++)
254                                                   296 
255 #define bio_for_each_segment(bvl, bio, i)         297 #define bio_for_each_segment(bvl, bio, i)                               \
256         __bio_for_each_segment(bvl, bio, i, (b    298         __bio_for_each_segment(bvl, bio, i, (bio)->bi_idx)
257                                                   299 
258 /*                                                300 /*
259  * get a reference to a bio, so it won't disap    301  * get a reference to a bio, so it won't disappear. the intended use is
260  * something like:                                302  * something like:
261  *                                                303  *
262  * bio_get(bio);                                  304  * bio_get(bio);
263  * submit_bio(rw, bio);                           305  * submit_bio(rw, bio);
264  * if (bio->bi_flags ...)                         306  * if (bio->bi_flags ...)
265  *      do_something                              307  *      do_something
266  * bio_put(bio);                                  308  * bio_put(bio);
267  *                                                309  *
268  * without the bio_get(), it could potentially    310  * without the bio_get(), it could potentially complete I/O before submit_bio
269  * returns. and then bio would be freed memory    311  * returns. and then bio would be freed memory when if (bio->bi_flags ...)
270  * runs                                           312  * runs
271  */                                               313  */
272 #define bio_get(bio)    atomic_inc(&(bio)->bi_    314 #define bio_get(bio)    atomic_inc(&(bio)->bi_cnt)
273                                                   315 
                                                   >> 316 #if defined(CONFIG_BLK_DEV_INTEGRITY)
                                                   >> 317 /*
                                                   >> 318  * bio integrity payload
                                                   >> 319  */
                                                   >> 320 struct bio_integrity_payload {
                                                   >> 321         struct bio              *bip_bio;       /* parent bio */
                                                   >> 322 
                                                   >> 323         sector_t                bip_sector;     /* virtual start sector */
                                                   >> 324 
                                                   >> 325         void                    *bip_buf;       /* generated integrity data */
                                                   >> 326         bio_end_io_t            *bip_end_io;    /* saved I/O completion fn */
                                                   >> 327 
                                                   >> 328         unsigned int            bip_size;
                                                   >> 329 
                                                   >> 330         unsigned short          bip_slab;       /* slab the bip came from */
                                                   >> 331         unsigned short          bip_vcnt;       /* # of integrity bio_vecs */
                                                   >> 332         unsigned short          bip_idx;        /* current bip_vec index */
                                                   >> 333 
                                                   >> 334         struct work_struct      bip_work;       /* I/O completion */
                                                   >> 335         struct bio_vec          bip_vec[0];     /* embedded bvec array */
                                                   >> 336 };
                                                   >> 337 #endif /* CONFIG_BLK_DEV_INTEGRITY */
274                                                   338 
275 /*                                                339 /*
276  * A bio_pair is used when we need to split a     340  * A bio_pair is used when we need to split a bio.
277  * This can only happen for a bio that refers     341  * This can only happen for a bio that refers to just one
278  * page of data, and in the unusual situation     342  * page of data, and in the unusual situation when the
279  * page crosses a chunk/device boundary           343  * page crosses a chunk/device boundary
280  *                                                344  *
281  * The address of the master bio is stored in     345  * The address of the master bio is stored in bio1.bi_private
282  * The address of the pool the pair was alloca    346  * The address of the pool the pair was allocated from is stored
283  *   in bio2.bi_private                           347  *   in bio2.bi_private
284  */                                               348  */
285 struct bio_pair {                                 349 struct bio_pair {
286         struct bio      bio1, bio2;            !! 350         struct bio                      bio1, bio2;
287         struct bio_vec  bv1, bv2;              !! 351         struct bio_vec                  bv1, bv2;
288         atomic_t        cnt;                   !! 352 #if defined(CONFIG_BLK_DEV_INTEGRITY)
289         int             error;                 !! 353         struct bio_integrity_payload    bip1, bip2;
                                                   >> 354         struct bio_vec                  iv1, iv2;
                                                   >> 355 #endif
                                                   >> 356         atomic_t                        cnt;
                                                   >> 357         int                             error;
290 };                                                358 };
291 extern struct bio_pair *bio_split(struct bio * !! 359 extern struct bio_pair *bio_split(struct bio *bi, int first_sectors);
292                                   int first_se << 
293 extern mempool_t *bio_split_pool;              << 
294 extern void bio_pair_release(struct bio_pair *    360 extern void bio_pair_release(struct bio_pair *dbio);
295                                                   361 
296 extern struct bio_set *bioset_create(int, int) !! 362 extern struct bio_set *bioset_create(unsigned int, unsigned int);
297 extern void bioset_free(struct bio_set *);        363 extern void bioset_free(struct bio_set *);
298                                                   364 
299 extern struct bio *bio_alloc(gfp_t, int);         365 extern struct bio *bio_alloc(gfp_t, int);
                                                   >> 366 extern struct bio *bio_kmalloc(gfp_t, int);
300 extern struct bio *bio_alloc_bioset(gfp_t, int    367 extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
301 extern void bio_put(struct bio *);                368 extern void bio_put(struct bio *);
302 extern void bio_free(struct bio *, struct bio_    369 extern void bio_free(struct bio *, struct bio_set *);
303                                                   370 
304 extern void bio_endio(struct bio *, int);         371 extern void bio_endio(struct bio *, int);
305 struct request_queue;                             372 struct request_queue;
306 extern int bio_phys_segments(struct request_qu    373 extern int bio_phys_segments(struct request_queue *, struct bio *);
307 extern int bio_hw_segments(struct request_queu << 
308                                                   374 
309 extern void __bio_clone(struct bio *, struct b    375 extern void __bio_clone(struct bio *, struct bio *);
310 extern struct bio *bio_clone(struct bio *, gfp    376 extern struct bio *bio_clone(struct bio *, gfp_t);
311                                                   377 
312 extern void bio_init(struct bio *);               378 extern void bio_init(struct bio *);
313                                                   379 
314 extern int bio_add_page(struct bio *, struct p    380 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
315 extern int bio_add_pc_page(struct request_queu    381 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
316                            unsigned int, unsig    382                            unsigned int, unsigned int);
317 extern int bio_get_nr_vecs(struct block_device    383 extern int bio_get_nr_vecs(struct block_device *);
                                                   >> 384 extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int);
318 extern struct bio *bio_map_user(struct request    385 extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
319                                 unsigned long, !! 386                                 unsigned long, unsigned int, int, gfp_t);
320 struct sg_iovec;                                  387 struct sg_iovec;
                                                   >> 388 struct rq_map_data;
321 extern struct bio *bio_map_user_iov(struct req    389 extern struct bio *bio_map_user_iov(struct request_queue *,
322                                     struct blo    390                                     struct block_device *,
323                                     struct sg_ !! 391                                     struct sg_iovec *, int, int, gfp_t);
324 extern void bio_unmap_user(struct bio *);         392 extern void bio_unmap_user(struct bio *);
325 extern struct bio *bio_map_kern(struct request    393 extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
326                                 gfp_t);           394                                 gfp_t);
                                                   >> 395 extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
                                                   >> 396                                  gfp_t, int);
327 extern void bio_set_pages_dirty(struct bio *bi    397 extern void bio_set_pages_dirty(struct bio *bio);
328 extern void bio_check_pages_dirty(struct bio *    398 extern void bio_check_pages_dirty(struct bio *bio);
329 extern struct bio *bio_copy_user(struct reques !! 399 extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
                                                   >> 400                                  unsigned long, unsigned int, int, gfp_t);
                                                   >> 401 extern struct bio *bio_copy_user_iov(struct request_queue *,
                                                   >> 402                                      struct rq_map_data *, struct sg_iovec *,
                                                   >> 403                                      int, int, gfp_t);
330 extern int bio_uncopy_user(struct bio *);         404 extern int bio_uncopy_user(struct bio *);
331 void zero_fill_bio(struct bio *bio);              405 void zero_fill_bio(struct bio *bio);
                                                   >> 406 extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *);
                                                   >> 407 extern void bvec_free_bs(struct bio_set *, struct bio_vec *, unsigned int);
                                                   >> 408 extern unsigned int bvec_nr_vecs(unsigned short idx);
                                                   >> 409 
                                                   >> 410 /*
                                                   >> 411  * Allow queuer to specify a completion CPU for this bio
                                                   >> 412  */
                                                   >> 413 static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu)
                                                   >> 414 {
                                                   >> 415         bio->bi_comp_cpu = cpu;
                                                   >> 416 }
                                                   >> 417 
                                                   >> 418 /*
                                                   >> 419  * bio_set is used to allow other portions of the IO system to
                                                   >> 420  * allocate their own private memory pools for bio and iovec structures.
                                                   >> 421  * These memory pools in turn all allocate from the bio_slab
                                                   >> 422  * and the bvec_slabs[].
                                                   >> 423  */
                                                   >> 424 #define BIO_POOL_SIZE 2
                                                   >> 425 #define BIOVEC_NR_POOLS 6
                                                   >> 426 #define BIOVEC_MAX_IDX  (BIOVEC_NR_POOLS - 1)
                                                   >> 427 
                                                   >> 428 struct bio_set {
                                                   >> 429         struct kmem_cache *bio_slab;
                                                   >> 430         unsigned int front_pad;
                                                   >> 431 
                                                   >> 432         mempool_t *bio_pool;
                                                   >> 433 #if defined(CONFIG_BLK_DEV_INTEGRITY)
                                                   >> 434         mempool_t *bio_integrity_pool;
                                                   >> 435 #endif
                                                   >> 436         mempool_t *bvec_pool;
                                                   >> 437 };
                                                   >> 438 
                                                   >> 439 struct biovec_slab {
                                                   >> 440         int nr_vecs;
                                                   >> 441         char *name;
                                                   >> 442         struct kmem_cache *slab;
                                                   >> 443 };
                                                   >> 444 
                                                   >> 445 extern struct bio_set *fs_bio_set;
                                                   >> 446 extern struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly;
                                                   >> 447 
                                                   >> 448 /*
                                                   >> 449  * a small number of entries is fine, not going to be performance critical.
                                                   >> 450  * basically we just need to survive
                                                   >> 451  */
                                                   >> 452 #define BIO_SPLIT_ENTRIES 2
332                                                   453 
333 #ifdef CONFIG_HIGHMEM                             454 #ifdef CONFIG_HIGHMEM
334 /*                                                455 /*
335  * remember to add offset! and never ever reen !! 456  * remember never ever reenable interrupts between a bvec_kmap_irq and
336  * bvec_kmap_irq and bvec_kunmap_irq!!         !! 457  * bvec_kunmap_irq!
337  *                                                458  *
338  * This function MUST be inlined - it plays wi    459  * This function MUST be inlined - it plays with the CPU interrupt flags.
339  */                                               460  */
340 static inline char *bvec_kmap_irq(struct bio_v !! 461 static __always_inline char *bvec_kmap_irq(struct bio_vec *bvec,
                                                   >> 462                 unsigned long *flags)
341 {                                                 463 {
342         unsigned long addr;                       464         unsigned long addr;
343                                                   465 
344         /*                                        466         /*
345          * might not be a highmem page, but th    467          * might not be a highmem page, but the preempt/irq count
346          * balancing is a lot nicer this way      468          * balancing is a lot nicer this way
347          */                                       469          */
348         local_irq_save(*flags);                   470         local_irq_save(*flags);
349         addr = (unsigned long) kmap_atomic(bve    471         addr = (unsigned long) kmap_atomic(bvec->bv_page, KM_BIO_SRC_IRQ);
350                                                   472 
351         BUG_ON(addr & ~PAGE_MASK);                473         BUG_ON(addr & ~PAGE_MASK);
352                                                   474 
353         return (char *) addr + bvec->bv_offset    475         return (char *) addr + bvec->bv_offset;
354 }                                                 476 }
355                                                   477 
356 static inline void bvec_kunmap_irq(char *buffe !! 478 static __always_inline void bvec_kunmap_irq(char *buffer,
                                                   >> 479                 unsigned long *flags)
357 {                                                 480 {
358         unsigned long ptr = (unsigned long) bu    481         unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
359                                                   482 
360         kunmap_atomic((void *) ptr, KM_BIO_SRC    483         kunmap_atomic((void *) ptr, KM_BIO_SRC_IRQ);
361         local_irq_restore(*flags);                484         local_irq_restore(*flags);
362 }                                                 485 }
363                                                   486 
364 #else                                             487 #else
365 #define bvec_kmap_irq(bvec, flags)      (page_    488 #define bvec_kmap_irq(bvec, flags)      (page_address((bvec)->bv_page) + (bvec)->bv_offset)
366 #define bvec_kunmap_irq(buf, flags)     do { *    489 #define bvec_kunmap_irq(buf, flags)     do { *(flags) = 0; } while (0)
367 #endif                                            490 #endif
368                                                   491 
369 static inline char *__bio_kmap_irq(struct bio     492 static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx,
370                                    unsigned lo    493                                    unsigned long *flags)
371 {                                                 494 {
372         return bvec_kmap_irq(bio_iovec_idx(bio    495         return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags);
373 }                                                 496 }
374 #define __bio_kunmap_irq(buf, flags)    bvec_k    497 #define __bio_kunmap_irq(buf, flags)    bvec_kunmap_irq(buf, flags)
375                                                   498 
376 #define bio_kmap_irq(bio, flags) \                499 #define bio_kmap_irq(bio, flags) \
377         __bio_kmap_irq((bio), (bio)->bi_idx, (    500         __bio_kmap_irq((bio), (bio)->bi_idx, (flags))
378 #define bio_kunmap_irq(buf,flags)       __bio_    501 #define bio_kunmap_irq(buf,flags)       __bio_kunmap_irq(buf, flags)
379                                                   502 
                                                   >> 503 /*
                                                   >> 504  * Check whether this bio carries any data or not. A NULL bio is allowed.
                                                   >> 505  */
                                                   >> 506 static inline int bio_has_data(struct bio *bio)
                                                   >> 507 {
                                                   >> 508         return bio && bio->bi_io_vec != NULL;
                                                   >> 509 }
                                                   >> 510 
                                                   >> 511 /*
                                                   >> 512  * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
                                                   >> 513  *
                                                   >> 514  * A bio_list anchors a singly-linked list of bios chained through the bi_next
                                                   >> 515  * member of the bio.  The bio_list also caches the last list member to allow
                                                   >> 516  * fast access to the tail.
                                                   >> 517  */
                                                   >> 518 struct bio_list {
                                                   >> 519         struct bio *head;
                                                   >> 520         struct bio *tail;
                                                   >> 521 };
                                                   >> 522 
                                                   >> 523 static inline int bio_list_empty(const struct bio_list *bl)
                                                   >> 524 {
                                                   >> 525         return bl->head == NULL;
                                                   >> 526 }
                                                   >> 527 
                                                   >> 528 static inline void bio_list_init(struct bio_list *bl)
                                                   >> 529 {
                                                   >> 530         bl->head = bl->tail = NULL;
                                                   >> 531 }
                                                   >> 532 
                                                   >> 533 #define bio_list_for_each(bio, bl) \
                                                   >> 534         for (bio = (bl)->head; bio; bio = bio->bi_next)
                                                   >> 535 
                                                   >> 536 static inline unsigned bio_list_size(const struct bio_list *bl)
                                                   >> 537 {
                                                   >> 538         unsigned sz = 0;
                                                   >> 539         struct bio *bio;
                                                   >> 540 
                                                   >> 541         bio_list_for_each(bio, bl)
                                                   >> 542                 sz++;
                                                   >> 543 
                                                   >> 544         return sz;
                                                   >> 545 }
                                                   >> 546 
                                                   >> 547 static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
                                                   >> 548 {
                                                   >> 549         bio->bi_next = NULL;
                                                   >> 550 
                                                   >> 551         if (bl->tail)
                                                   >> 552                 bl->tail->bi_next = bio;
                                                   >> 553         else
                                                   >> 554                 bl->head = bio;
                                                   >> 555 
                                                   >> 556         bl->tail = bio;
                                                   >> 557 }
                                                   >> 558 
                                                   >> 559 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
                                                   >> 560 {
                                                   >> 561         bio->bi_next = bl->head;
                                                   >> 562 
                                                   >> 563         bl->head = bio;
                                                   >> 564 
                                                   >> 565         if (!bl->tail)
                                                   >> 566                 bl->tail = bio;
                                                   >> 567 }
                                                   >> 568 
                                                   >> 569 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
                                                   >> 570 {
                                                   >> 571         if (!bl2->head)
                                                   >> 572                 return;
                                                   >> 573 
                                                   >> 574         if (bl->tail)
                                                   >> 575                 bl->tail->bi_next = bl2->head;
                                                   >> 576         else
                                                   >> 577                 bl->head = bl2->head;
                                                   >> 578 
                                                   >> 579         bl->tail = bl2->tail;
                                                   >> 580 }
                                                   >> 581 
                                                   >> 582 static inline void bio_list_merge_head(struct bio_list *bl,
                                                   >> 583                                        struct bio_list *bl2)
                                                   >> 584 {
                                                   >> 585         if (!bl2->head)
                                                   >> 586                 return;
                                                   >> 587 
                                                   >> 588         if (bl->head)
                                                   >> 589                 bl2->tail->bi_next = bl->head;
                                                   >> 590         else
                                                   >> 591                 bl->tail = bl2->tail;
                                                   >> 592 
                                                   >> 593         bl->head = bl2->head;
                                                   >> 594 }
                                                   >> 595 
                                                   >> 596 static inline struct bio *bio_list_peek(struct bio_list *bl)
                                                   >> 597 {
                                                   >> 598         return bl->head;
                                                   >> 599 }
                                                   >> 600 
                                                   >> 601 static inline struct bio *bio_list_pop(struct bio_list *bl)
                                                   >> 602 {
                                                   >> 603         struct bio *bio = bl->head;
                                                   >> 604 
                                                   >> 605         if (bio) {
                                                   >> 606                 bl->head = bl->head->bi_next;
                                                   >> 607                 if (!bl->head)
                                                   >> 608                         bl->tail = NULL;
                                                   >> 609 
                                                   >> 610                 bio->bi_next = NULL;
                                                   >> 611         }
                                                   >> 612 
                                                   >> 613         return bio;
                                                   >> 614 }
                                                   >> 615 
                                                   >> 616 static inline struct bio *bio_list_get(struct bio_list *bl)
                                                   >> 617 {
                                                   >> 618         struct bio *bio = bl->head;
                                                   >> 619 
                                                   >> 620         bl->head = bl->tail = NULL;
                                                   >> 621 
                                                   >> 622         return bio;
                                                   >> 623 }
                                                   >> 624 
                                                   >> 625 #if defined(CONFIG_BLK_DEV_INTEGRITY)
                                                   >> 626 
                                                   >> 627 #define bip_vec_idx(bip, idx)   (&(bip->bip_vec[(idx)]))
                                                   >> 628 #define bip_vec(bip)            bip_vec_idx(bip, 0)
                                                   >> 629 
                                                   >> 630 #define __bip_for_each_vec(bvl, bip, i, start_idx)                      \
                                                   >> 631         for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx);    \
                                                   >> 632              i < (bip)->bip_vcnt;                                       \
                                                   >> 633              bvl++, i++)
                                                   >> 634 
                                                   >> 635 #define bip_for_each_vec(bvl, bip, i)                                   \
                                                   >> 636         __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
                                                   >> 637 
                                                   >> 638 #define bio_integrity(bio) (bio->bi_integrity != NULL)
                                                   >> 639 
                                                   >> 640 extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *);
                                                   >> 641 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
                                                   >> 642 extern void bio_integrity_free(struct bio *, struct bio_set *);
                                                   >> 643 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
                                                   >> 644 extern int bio_integrity_enabled(struct bio *bio);
                                                   >> 645 extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
                                                   >> 646 extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
                                                   >> 647 extern int bio_integrity_prep(struct bio *);
                                                   >> 648 extern void bio_integrity_endio(struct bio *, int);
                                                   >> 649 extern void bio_integrity_advance(struct bio *, unsigned int);
                                                   >> 650 extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
                                                   >> 651 extern void bio_integrity_split(struct bio *, struct bio_pair *, int);
                                                   >> 652 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t, struct bio_set *);
                                                   >> 653 extern int bioset_integrity_create(struct bio_set *, int);
                                                   >> 654 extern void bioset_integrity_free(struct bio_set *);
                                                   >> 655 extern void bio_integrity_init(void);
                                                   >> 656 
                                                   >> 657 #else /* CONFIG_BLK_DEV_INTEGRITY */
                                                   >> 658 
                                                   >> 659 #define bio_integrity(a)                (0)
                                                   >> 660 #define bioset_integrity_create(a, b)   (0)
                                                   >> 661 #define bio_integrity_prep(a)           (0)
                                                   >> 662 #define bio_integrity_enabled(a)        (0)
                                                   >> 663 #define bio_integrity_clone(a, b, c, d) (0)
                                                   >> 664 #define bioset_integrity_free(a)        do { } while (0)
                                                   >> 665 #define bio_integrity_free(a, b)        do { } while (0)
                                                   >> 666 #define bio_integrity_endio(a, b)       do { } while (0)
                                                   >> 667 #define bio_integrity_advance(a, b)     do { } while (0)
                                                   >> 668 #define bio_integrity_trim(a, b, c)     do { } while (0)
                                                   >> 669 #define bio_integrity_split(a, b, c)    do { } while (0)
                                                   >> 670 #define bio_integrity_set_tag(a, b, c)  do { } while (0)
                                                   >> 671 #define bio_integrity_get_tag(a, b, c)  do { } while (0)
                                                   >> 672 #define bio_integrity_init(a)           do { } while (0)
                                                   >> 673 
                                                   >> 674 #endif /* CONFIG_BLK_DEV_INTEGRITY */
                                                   >> 675 
380 #endif /* CONFIG_BLOCK */                         676 #endif /* CONFIG_BLOCK */
381 #endif /* __LINUX_BIO_H */                        677 #endif /* __LINUX_BIO_H */
382                                                   678 
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