diff options
author | Zheng Da <zhengda1936@gmail.com> | 2009-12-06 05:26:23 +0100 |
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committer | Zheng Da <zhengda1936@gmail.com> | 2009-12-06 05:26:23 +0100 |
commit | 8a6d48c0542876eb3acfc0970c0ab7872db08d5f (patch) | |
tree | 496e78bc728317ea779781b92f897d16936ee231 /libdde_linux26/contrib/include/linux/bio.h | |
parent | b4bffcfcdf3ab7a55d664e9aa5907f88da503f38 (diff) |
check in the original version of dde linux26.
Diffstat (limited to 'libdde_linux26/contrib/include/linux/bio.h')
-rw-r--r-- | libdde_linux26/contrib/include/linux/bio.h | 559 |
1 files changed, 559 insertions, 0 deletions
diff --git a/libdde_linux26/contrib/include/linux/bio.h b/libdde_linux26/contrib/include/linux/bio.h new file mode 100644 index 00000000..d8bd43bf --- /dev/null +++ b/libdde_linux26/contrib/include/linux/bio.h @@ -0,0 +1,559 @@ +/* + * 2.5 block I/O model + * + * Copyright (C) 2001 Jens Axboe <axboe@suse.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public Licens + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- + */ +#ifndef __LINUX_BIO_H +#define __LINUX_BIO_H + +#include <linux/highmem.h> +#include <linux/mempool.h> +#include <linux/ioprio.h> + +#ifdef CONFIG_BLOCK + +#include <asm/io.h> + +#define BIO_DEBUG + +#ifdef BIO_DEBUG +#define BIO_BUG_ON BUG_ON +#else +#define BIO_BUG_ON +#endif + +#define BIO_MAX_PAGES 256 +#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT) +#define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9) + +/* + * was unsigned short, but we might as well be ready for > 64kB I/O pages + */ +struct bio_vec { + struct page *bv_page; + unsigned int bv_len; + unsigned int bv_offset; +}; + +struct bio_set; +struct bio; +struct bio_integrity_payload; +typedef void (bio_end_io_t) (struct bio *, int); +typedef void (bio_destructor_t) (struct bio *); + +/* + * main unit of I/O for the block layer and lower layers (ie drivers and + * stacking drivers) + */ +struct bio { + sector_t bi_sector; /* device address in 512 byte + sectors */ + struct bio *bi_next; /* request queue link */ + struct block_device *bi_bdev; + unsigned long bi_flags; /* status, command, etc */ + unsigned long bi_rw; /* bottom bits READ/WRITE, + * top bits priority + */ + + unsigned short bi_vcnt; /* how many bio_vec's */ + unsigned short bi_idx; /* current index into bvl_vec */ + + /* Number of segments in this BIO after + * physical address coalescing is performed. + */ + unsigned int bi_phys_segments; + + unsigned int bi_size; /* residual I/O count */ + + /* + * To keep track of the max segment size, we account for the + * sizes of the first and last mergeable segments in this bio. + */ + unsigned int bi_seg_front_size; + unsigned int bi_seg_back_size; + + unsigned int bi_max_vecs; /* max bvl_vecs we can hold */ + + unsigned int bi_comp_cpu; /* completion CPU */ + + atomic_t bi_cnt; /* pin count */ + + struct bio_vec *bi_io_vec; /* the actual vec list */ + + bio_end_io_t *bi_end_io; + + void *bi_private; +#if defined(CONFIG_BLK_DEV_INTEGRITY) + struct bio_integrity_payload *bi_integrity; /* data integrity */ +#endif + + bio_destructor_t *bi_destructor; /* destructor */ + + /* + * We can inline a number of vecs at the end of the bio, to avoid + * double allocations for a small number of bio_vecs. This member + * MUST obviously be kept at the very end of the bio. + */ + struct bio_vec bi_inline_vecs[0]; +}; + +/* + * bio flags + */ +#define BIO_UPTODATE 0 /* ok after I/O completion */ +#define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */ +#define BIO_EOF 2 /* out-out-bounds error */ +#define BIO_SEG_VALID 3 /* bi_phys_segments valid */ +#define BIO_CLONED 4 /* doesn't own data */ +#define BIO_BOUNCED 5 /* bio is a bounce bio */ +#define BIO_USER_MAPPED 6 /* contains user pages */ +#define BIO_EOPNOTSUPP 7 /* not supported */ +#define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */ +#define BIO_NULL_MAPPED 9 /* contains invalid user pages */ +#define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */ +#define BIO_QUIET 11 /* Make BIO Quiet */ +#define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) + +/* + * top 4 bits of bio flags indicate the pool this bio came from + */ +#define BIO_POOL_BITS (4) +#define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS) +#define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET) +#define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET) + +/* + * bio bi_rw flags + * + * bit 0 -- data direction + * If not set, bio is a read from device. If set, it's a write to device. + * bit 1 -- rw-ahead when set + * bit 2 -- barrier + * Insert a serialization point in the IO queue, forcing previously + * submitted IO to be completed before this one is issued. + * bit 3 -- synchronous I/O hint: the block layer will unplug immediately + * Note that this does NOT indicate that the IO itself is sync, just + * that the block layer will not postpone issue of this IO by plugging. + * bit 4 -- metadata request + * Used for tracing to differentiate metadata and data IO. May also + * get some preferential treatment in the IO scheduler + * bit 5 -- discard sectors + * Informs the lower level device that this range of sectors is no longer + * used by the file system and may thus be freed by the device. Used + * for flash based storage. + * bit 6 -- fail fast device errors + * bit 7 -- fail fast transport errors + * bit 8 -- fail fast driver errors + * Don't want driver retries for any fast fail whatever the reason. + */ +#define BIO_RW 0 /* Must match RW in req flags (blkdev.h) */ +#define BIO_RW_AHEAD 1 /* Must match FAILFAST in req flags */ +#define BIO_RW_BARRIER 2 +#define BIO_RW_SYNCIO 3 +#define BIO_RW_UNPLUG 4 +#define BIO_RW_META 5 +#define BIO_RW_DISCARD 6 +#define BIO_RW_FAILFAST_DEV 7 +#define BIO_RW_FAILFAST_TRANSPORT 8 +#define BIO_RW_FAILFAST_DRIVER 9 + +#define bio_rw_flagged(bio, flag) ((bio)->bi_rw & (1 << (flag))) + +/* + * Old defines, these should eventually be replaced by direct usage of + * bio_rw_flagged() + */ +#define bio_barrier(bio) bio_rw_flagged(bio, BIO_RW_BARRIER) +#define bio_sync(bio) bio_rw_flagged(bio, BIO_RW_SYNCIO) +#define bio_unplug(bio) bio_rw_flagged(bio, BIO_RW_UNPLUG) +#define bio_failfast_dev(bio) bio_rw_flagged(bio, BIO_RW_FAILFAST_DEV) +#define bio_failfast_transport(bio) \ + bio_rw_flagged(bio, BIO_RW_FAILFAST_TRANSPORT) +#define bio_failfast_driver(bio) \ + bio_rw_flagged(bio, BIO_RW_FAILFAST_DRIVER) +#define bio_rw_ahead(bio) bio_rw_flagged(bio, BIO_RW_AHEAD) +#define bio_rw_meta(bio) bio_rw_flagged(bio, BIO_RW_META) +#define bio_discard(bio) bio_rw_flagged(bio, BIO_RW_DISCARD) + +/* + * upper 16 bits of bi_rw define the io priority of this bio + */ +#define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS) +#define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT) +#define bio_prio_valid(bio) ioprio_valid(bio_prio(bio)) + +#define bio_set_prio(bio, prio) do { \ + WARN_ON(prio >= (1 << IOPRIO_BITS)); \ + (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \ + (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \ +} while (0) + +/* + * various member access, note that bio_data should of course not be used + * on highmem page vectors + */ +#define bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)])) +#define bio_iovec(bio) bio_iovec_idx((bio), (bio)->bi_idx) +#define bio_page(bio) bio_iovec((bio))->bv_page +#define bio_offset(bio) bio_iovec((bio))->bv_offset +#define bio_segments(bio) ((bio)->bi_vcnt - (bio)->bi_idx) +#define bio_sectors(bio) ((bio)->bi_size >> 9) +#define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio) && !bio_discard(bio)) + +static inline unsigned int bio_cur_sectors(struct bio *bio) +{ + if (bio->bi_vcnt) + return bio_iovec(bio)->bv_len >> 9; + else /* dataless requests such as discard */ + return bio->bi_size >> 9; +} + +static inline void *bio_data(struct bio *bio) +{ + if (bio->bi_vcnt) + return page_address(bio_page(bio)) + bio_offset(bio); + + return NULL; +} + +static inline int bio_has_allocated_vec(struct bio *bio) +{ + return bio->bi_io_vec && bio->bi_io_vec != bio->bi_inline_vecs; +} + +/* + * will die + */ +#define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio))) +#define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset) + +/* + * queues that have highmem support enabled may still need to revert to + * PIO transfers occasionally and thus map high pages temporarily. For + * permanent PIO fall back, user is probably better off disabling highmem + * I/O completely on that queue (see ide-dma for example) + */ +#define __bio_kmap_atomic(bio, idx, kmtype) \ + (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page, kmtype) + \ + bio_iovec_idx((bio), (idx))->bv_offset) + +#define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr, kmtype) + +/* + * merge helpers etc + */ + +#define __BVEC_END(bio) bio_iovec_idx((bio), (bio)->bi_vcnt - 1) +#define __BVEC_START(bio) bio_iovec_idx((bio), (bio)->bi_idx) + +/* Default implementation of BIOVEC_PHYS_MERGEABLE */ +#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ + ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2))) + +/* + * allow arch override, for eg virtualized architectures (put in asm/io.h) + */ +#ifndef BIOVEC_PHYS_MERGEABLE +#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ + __BIOVEC_PHYS_MERGEABLE(vec1, vec2) +#endif + +#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \ + (((addr1) | (mask)) == (((addr2) - 1) | (mask))) +#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \ + __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, (q)->seg_boundary_mask) +#define BIO_SEG_BOUNDARY(q, b1, b2) \ + BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2))) + +#define bio_io_error(bio) bio_endio((bio), -EIO) + +/* + * drivers should not use the __ version unless they _really_ want to + * run through the entire bio and not just pending pieces + */ +#define __bio_for_each_segment(bvl, bio, i, start_idx) \ + for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx); \ + i < (bio)->bi_vcnt; \ + bvl++, i++) + +#define bio_for_each_segment(bvl, bio, i) \ + __bio_for_each_segment(bvl, bio, i, (bio)->bi_idx) + +/* + * get a reference to a bio, so it won't disappear. the intended use is + * something like: + * + * bio_get(bio); + * submit_bio(rw, bio); + * if (bio->bi_flags ...) + * do_something + * bio_put(bio); + * + * without the bio_get(), it could potentially complete I/O before submit_bio + * returns. and then bio would be freed memory when if (bio->bi_flags ...) + * runs + */ +#define bio_get(bio) atomic_inc(&(bio)->bi_cnt) + +#if defined(CONFIG_BLK_DEV_INTEGRITY) +/* + * bio integrity payload + */ +struct bio_integrity_payload { + struct bio *bip_bio; /* parent bio */ + struct bio_vec *bip_vec; /* integrity data vector */ + + sector_t bip_sector; /* virtual start sector */ + + void *bip_buf; /* generated integrity data */ + bio_end_io_t *bip_end_io; /* saved I/O completion fn */ + + unsigned int bip_size; + + unsigned short bip_pool; /* pool the ivec came from */ + unsigned short bip_vcnt; /* # of integrity bio_vecs */ + unsigned short bip_idx; /* current bip_vec index */ + + struct work_struct bip_work; /* I/O completion */ +}; +#endif /* CONFIG_BLK_DEV_INTEGRITY */ + +/* + * A bio_pair is used when we need to split a bio. + * This can only happen for a bio that refers to just one + * page of data, and in the unusual situation when the + * page crosses a chunk/device boundary + * + * The address of the master bio is stored in bio1.bi_private + * The address of the pool the pair was allocated from is stored + * in bio2.bi_private + */ +struct bio_pair { + struct bio bio1, bio2; + struct bio_vec bv1, bv2; +#if defined(CONFIG_BLK_DEV_INTEGRITY) + struct bio_integrity_payload bip1, bip2; + struct bio_vec iv1, iv2; +#endif + atomic_t cnt; + int error; +}; +extern struct bio_pair *bio_split(struct bio *bi, int first_sectors); +extern void bio_pair_release(struct bio_pair *dbio); + +extern struct bio_set *bioset_create(unsigned int, unsigned int); +extern void bioset_free(struct bio_set *); + +extern struct bio *bio_alloc(gfp_t, int); +extern struct bio *bio_kmalloc(gfp_t, int); +extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *); +extern void bio_put(struct bio *); +extern void bio_free(struct bio *, struct bio_set *); + +extern void bio_endio(struct bio *, int); +struct request_queue; +extern int bio_phys_segments(struct request_queue *, struct bio *); + +extern void __bio_clone(struct bio *, struct bio *); +extern struct bio *bio_clone(struct bio *, gfp_t); + +extern void bio_init(struct bio *); + +extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); +extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, + unsigned int, unsigned int); +extern int bio_get_nr_vecs(struct block_device *); +extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int); +extern struct bio *bio_map_user(struct request_queue *, struct block_device *, + unsigned long, unsigned int, int, gfp_t); +struct sg_iovec; +struct rq_map_data; +extern struct bio *bio_map_user_iov(struct request_queue *, + struct block_device *, + struct sg_iovec *, int, int, gfp_t); +extern void bio_unmap_user(struct bio *); +extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, + gfp_t); +extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, + gfp_t, int); +extern void bio_set_pages_dirty(struct bio *bio); +extern void bio_check_pages_dirty(struct bio *bio); +extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *, + unsigned long, unsigned int, int, gfp_t); +extern struct bio *bio_copy_user_iov(struct request_queue *, + struct rq_map_data *, struct sg_iovec *, + int, int, gfp_t); +extern int bio_uncopy_user(struct bio *); +void zero_fill_bio(struct bio *bio); +extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *); +extern void bvec_free_bs(struct bio_set *, struct bio_vec *, unsigned int); +extern unsigned int bvec_nr_vecs(unsigned short idx); + +/* + * Allow queuer to specify a completion CPU for this bio + */ +static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu) +{ + bio->bi_comp_cpu = cpu; +} + +/* + * bio_set is used to allow other portions of the IO system to + * allocate their own private memory pools for bio and iovec structures. + * These memory pools in turn all allocate from the bio_slab + * and the bvec_slabs[]. + */ +#define BIO_POOL_SIZE 2 +#define BIOVEC_NR_POOLS 6 +#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1) + +struct bio_set { + struct kmem_cache *bio_slab; + unsigned int front_pad; + + mempool_t *bio_pool; +#if defined(CONFIG_BLK_DEV_INTEGRITY) + mempool_t *bio_integrity_pool; +#endif + mempool_t *bvec_pool; +}; + +struct biovec_slab { + int nr_vecs; + char *name; + struct kmem_cache *slab; +}; + +extern struct bio_set *fs_bio_set; +extern struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly; + +/* + * a small number of entries is fine, not going to be performance critical. + * basically we just need to survive + */ +#define BIO_SPLIT_ENTRIES 2 + +#ifdef CONFIG_HIGHMEM +/* + * remember never ever reenable interrupts between a bvec_kmap_irq and + * bvec_kunmap_irq! + * + * This function MUST be inlined - it plays with the CPU interrupt flags. + */ +static __always_inline char *bvec_kmap_irq(struct bio_vec *bvec, + unsigned long *flags) +{ + unsigned long addr; + + /* + * might not be a highmem page, but the preempt/irq count + * balancing is a lot nicer this way + */ + local_irq_save(*flags); + addr = (unsigned long) kmap_atomic(bvec->bv_page, KM_BIO_SRC_IRQ); + + BUG_ON(addr & ~PAGE_MASK); + + return (char *) addr + bvec->bv_offset; +} + +static __always_inline void bvec_kunmap_irq(char *buffer, + unsigned long *flags) +{ + unsigned long ptr = (unsigned long) buffer & PAGE_MASK; + + kunmap_atomic((void *) ptr, KM_BIO_SRC_IRQ); + local_irq_restore(*flags); +} + +#else +#define bvec_kmap_irq(bvec, flags) (page_address((bvec)->bv_page) + (bvec)->bv_offset) +#define bvec_kunmap_irq(buf, flags) do { *(flags) = 0; } while (0) +#endif + +static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx, + unsigned long *flags) +{ + return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags); +} +#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags) + +#define bio_kmap_irq(bio, flags) \ + __bio_kmap_irq((bio), (bio)->bi_idx, (flags)) +#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags) + +/* + * Check whether this bio carries any data or not. A NULL bio is allowed. + */ +static inline int bio_has_data(struct bio *bio) +{ + return bio && bio->bi_io_vec != NULL; +} + +#if defined(CONFIG_BLK_DEV_INTEGRITY) + +#define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)])) +#define bip_vec(bip) bip_vec_idx(bip, 0) + +#define __bip_for_each_vec(bvl, bip, i, start_idx) \ + for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \ + i < (bip)->bip_vcnt; \ + bvl++, i++) + +#define bip_for_each_vec(bvl, bip, i) \ + __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx) + +#define bio_integrity(bio) (bio->bi_integrity != NULL) + +extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *); +extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); +extern void bio_integrity_free(struct bio *, struct bio_set *); +extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); +extern int bio_integrity_enabled(struct bio *bio); +extern int bio_integrity_set_tag(struct bio *, void *, unsigned int); +extern int bio_integrity_get_tag(struct bio *, void *, unsigned int); +extern int bio_integrity_prep(struct bio *); +extern void bio_integrity_endio(struct bio *, int); +extern void bio_integrity_advance(struct bio *, unsigned int); +extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int); +extern void bio_integrity_split(struct bio *, struct bio_pair *, int); +extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t, struct bio_set *); +extern int bioset_integrity_create(struct bio_set *, int); +extern void bioset_integrity_free(struct bio_set *); +extern void bio_integrity_init_slab(void); + +#else /* CONFIG_BLK_DEV_INTEGRITY */ + +#define bio_integrity(a) (0) +#define bioset_integrity_create(a, b) (0) +#define bio_integrity_prep(a) (0) +#define bio_integrity_enabled(a) (0) +#define bio_integrity_clone(a, b, c,d ) (0) +#define bioset_integrity_free(a) do { } while (0) +#define bio_integrity_free(a, b) do { } while (0) +#define bio_integrity_endio(a, b) do { } while (0) +#define bio_integrity_advance(a, b) do { } while (0) +#define bio_integrity_trim(a, b, c) do { } while (0) +#define bio_integrity_split(a, b, c) do { } while (0) +#define bio_integrity_set_tag(a, b, c) do { } while (0) +#define bio_integrity_get_tag(a, b, c) do { } while (0) +#define bio_integrity_init_slab(a) do { } while (0) + +#endif /* CONFIG_BLK_DEV_INTEGRITY */ + +#endif /* CONFIG_BLOCK */ +#endif /* __LINUX_BIO_H */ |