linux_dsm_epyc7002/include/linux/bio.h
Christoph Hellwig ff896738be block: return from __bio_try_merge_page if merging occured in the same page
We currently have an input same_page parameter to __bio_try_merge_page
to prohibit merging in the same page.  The rationale for that is that
some callers need to account for every page added to a bio.  Instead of
letting these callers call twice into the merge code to account for the
new vs existing page cases, just turn the paramter into an output one that
returns if a merge in the same page occured and let them act accordingly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-17 09:33:02 -06:00

835 lines
21 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2001 Jens Axboe <axboe@suse.de>
*/
#ifndef __LINUX_BIO_H
#define __LINUX_BIO_H
#include <linux/highmem.h>
#include <linux/mempool.h>
#include <linux/ioprio.h>
#ifdef CONFIG_BLOCK
/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
#include <linux/blk_types.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_prio(bio) (bio)->bi_ioprio
#define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
#define bio_iter_iovec(bio, iter) \
bvec_iter_bvec((bio)->bi_io_vec, (iter))
#define bio_iter_page(bio, iter) \
bvec_iter_page((bio)->bi_io_vec, (iter))
#define bio_iter_len(bio, iter) \
bvec_iter_len((bio)->bi_io_vec, (iter))
#define bio_iter_offset(bio, iter) \
bvec_iter_offset((bio)->bi_io_vec, (iter))
#define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
#define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
#define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
#define bio_multiple_segments(bio) \
((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
#define bvec_iter_sectors(iter) ((iter).bi_size >> 9)
#define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter)))
#define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter)
#define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter)
/*
* Return the data direction, READ or WRITE.
*/
#define bio_data_dir(bio) \
(op_is_write(bio_op(bio)) ? WRITE : READ)
/*
* Check whether this bio carries any data or not. A NULL bio is allowed.
*/
static inline bool bio_has_data(struct bio *bio)
{
if (bio &&
bio->bi_iter.bi_size &&
bio_op(bio) != REQ_OP_DISCARD &&
bio_op(bio) != REQ_OP_SECURE_ERASE &&
bio_op(bio) != REQ_OP_WRITE_ZEROES)
return true;
return false;
}
static inline bool bio_no_advance_iter(struct bio *bio)
{
return bio_op(bio) == REQ_OP_DISCARD ||
bio_op(bio) == REQ_OP_SECURE_ERASE ||
bio_op(bio) == REQ_OP_WRITE_SAME ||
bio_op(bio) == REQ_OP_WRITE_ZEROES;
}
static inline bool bio_mergeable(struct bio *bio)
{
if (bio->bi_opf & REQ_NOMERGE_FLAGS)
return false;
return true;
}
static inline unsigned int bio_cur_bytes(struct bio *bio)
{
if (bio_has_data(bio))
return bio_iovec(bio).bv_len;
else /* dataless requests such as discard */
return bio->bi_iter.bi_size;
}
static inline void *bio_data(struct bio *bio)
{
if (bio_has_data(bio))
return page_address(bio_page(bio)) + bio_offset(bio);
return NULL;
}
static inline bool bio_full(struct bio *bio)
{
return bio->bi_vcnt >= bio->bi_max_vecs;
}
static inline bool bio_next_segment(const struct bio *bio,
struct bvec_iter_all *iter)
{
if (iter->idx >= bio->bi_vcnt)
return false;
bvec_advance(&bio->bi_io_vec[iter->idx], iter);
return true;
}
/*
* drivers should _never_ use the all version - the bio may have been split
* before it got to the driver and the driver won't own all of it
*/
#define bio_for_each_segment_all(bvl, bio, iter) \
for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); )
static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
unsigned bytes)
{
iter->bi_sector += bytes >> 9;
if (bio_no_advance_iter(bio))
iter->bi_size -= bytes;
else
bvec_iter_advance(bio->bi_io_vec, iter, bytes);
/* TODO: It is reasonable to complete bio with error here. */
}
#define __bio_for_each_segment(bvl, bio, iter, start) \
for (iter = (start); \
(iter).bi_size && \
((bvl = bio_iter_iovec((bio), (iter))), 1); \
bio_advance_iter((bio), &(iter), (bvl).bv_len))
#define bio_for_each_segment(bvl, bio, iter) \
__bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
#define __bio_for_each_bvec(bvl, bio, iter, start) \
for (iter = (start); \
(iter).bi_size && \
((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \
bio_advance_iter((bio), &(iter), (bvl).bv_len))
/* iterate over multi-page bvec */
#define bio_for_each_bvec(bvl, bio, iter) \
__bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter)
#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
static inline unsigned bio_segments(struct bio *bio)
{
unsigned segs = 0;
struct bio_vec bv;
struct bvec_iter iter;
/*
* We special case discard/write same/write zeroes, because they
* interpret bi_size differently:
*/
switch (bio_op(bio)) {
case REQ_OP_DISCARD:
case REQ_OP_SECURE_ERASE:
case REQ_OP_WRITE_ZEROES:
return 0;
case REQ_OP_WRITE_SAME:
return 1;
default:
break;
}
bio_for_each_segment(bv, bio, iter)
segs++;
return segs;
}
/*
* 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
*/
static inline void bio_get(struct bio *bio)
{
bio->bi_flags |= (1 << BIO_REFFED);
smp_mb__before_atomic();
atomic_inc(&bio->__bi_cnt);
}
static inline void bio_cnt_set(struct bio *bio, unsigned int count)
{
if (count != 1) {
bio->bi_flags |= (1 << BIO_REFFED);
smp_mb();
}
atomic_set(&bio->__bi_cnt, count);
}
static inline bool bio_flagged(struct bio *bio, unsigned int bit)
{
return (bio->bi_flags & (1U << bit)) != 0;
}
static inline void bio_set_flag(struct bio *bio, unsigned int bit)
{
bio->bi_flags |= (1U << bit);
}
static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
{
bio->bi_flags &= ~(1U << bit);
}
static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv)
{
*bv = bio_iovec(bio);
}
static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv)
{
struct bvec_iter iter = bio->bi_iter;
int idx;
if (unlikely(!bio_multiple_segments(bio))) {
*bv = bio_iovec(bio);
return;
}
bio_advance_iter(bio, &iter, iter.bi_size);
if (!iter.bi_bvec_done)
idx = iter.bi_idx - 1;
else /* in the middle of bvec */
idx = iter.bi_idx;
*bv = bio->bi_io_vec[idx];
/*
* iter.bi_bvec_done records actual length of the last bvec
* if this bio ends in the middle of one io vector
*/
if (iter.bi_bvec_done)
bv->bv_len = iter.bi_bvec_done;
}
static inline struct bio_vec *bio_first_bvec_all(struct bio *bio)
{
WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
return bio->bi_io_vec;
}
static inline struct page *bio_first_page_all(struct bio *bio)
{
return bio_first_bvec_all(bio)->bv_page;
}
static inline struct bio_vec *bio_last_bvec_all(struct bio *bio)
{
WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
return &bio->bi_io_vec[bio->bi_vcnt - 1];
}
enum bip_flags {
BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
};
/*
* bio integrity payload
*/
struct bio_integrity_payload {
struct bio *bip_bio; /* parent bio */
struct bvec_iter bip_iter;
unsigned short bip_slab; /* slab the bip came from */
unsigned short bip_vcnt; /* # of integrity bio_vecs */
unsigned short bip_max_vcnt; /* integrity bio_vec slots */
unsigned short bip_flags; /* control flags */
struct bvec_iter bio_iter; /* for rewinding parent bio */
struct work_struct bip_work; /* I/O completion */
struct bio_vec *bip_vec;
struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
};
#if defined(CONFIG_BLK_DEV_INTEGRITY)
static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
{
if (bio->bi_opf & REQ_INTEGRITY)
return bio->bi_integrity;
return NULL;
}
static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
{
struct bio_integrity_payload *bip = bio_integrity(bio);
if (bip)
return bip->bip_flags & flag;
return false;
}
static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
{
return bip->bip_iter.bi_sector;
}
static inline void bip_set_seed(struct bio_integrity_payload *bip,
sector_t seed)
{
bip->bip_iter.bi_sector = seed;
}
#endif /* CONFIG_BLK_DEV_INTEGRITY */
extern void bio_trim(struct bio *bio, int offset, int size);
extern struct bio *bio_split(struct bio *bio, int sectors,
gfp_t gfp, struct bio_set *bs);
/**
* bio_next_split - get next @sectors from a bio, splitting if necessary
* @bio: bio to split
* @sectors: number of sectors to split from the front of @bio
* @gfp: gfp mask
* @bs: bio set to allocate from
*
* Returns a bio representing the next @sectors of @bio - if the bio is smaller
* than @sectors, returns the original bio unchanged.
*/
static inline struct bio *bio_next_split(struct bio *bio, int sectors,
gfp_t gfp, struct bio_set *bs)
{
if (sectors >= bio_sectors(bio))
return bio;
return bio_split(bio, sectors, gfp, bs);
}
enum {
BIOSET_NEED_BVECS = BIT(0),
BIOSET_NEED_RESCUER = BIT(1),
};
extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags);
extern void bioset_exit(struct bio_set *);
extern int biovec_init_pool(mempool_t *pool, int pool_entries);
extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src);
extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *);
extern void bio_put(struct bio *);
extern void __bio_clone_fast(struct bio *, struct bio *);
extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
extern struct bio_set fs_bio_set;
static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
{
return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set);
}
static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
{
return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
}
extern blk_qc_t submit_bio(struct bio *);
extern void bio_endio(struct bio *);
static inline void bio_io_error(struct bio *bio)
{
bio->bi_status = BLK_STS_IOERR;
bio_endio(bio);
}
static inline void bio_wouldblock_error(struct bio *bio)
{
bio->bi_status = BLK_STS_AGAIN;
bio_endio(bio);
}
struct request_queue;
extern int bio_phys_segments(struct request_queue *, struct bio *);
extern int submit_bio_wait(struct bio *bio);
extern void bio_advance(struct bio *, unsigned);
extern void bio_init(struct bio *bio, struct bio_vec *table,
unsigned short max_vecs);
extern void bio_uninit(struct bio *);
extern void bio_reset(struct bio *);
void bio_chain(struct bio *, 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);
bool __bio_try_merge_page(struct bio *bio, struct page *page,
unsigned int len, unsigned int off, bool *same_page);
void __bio_add_page(struct bio *bio, struct page *page,
unsigned int len, unsigned int off);
int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
struct rq_map_data;
extern struct bio *bio_map_user_iov(struct request_queue *,
struct iov_iter *, 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);
void generic_start_io_acct(struct request_queue *q, int op,
unsigned long sectors, struct hd_struct *part);
void generic_end_io_acct(struct request_queue *q, int op,
struct hd_struct *part,
unsigned long start_time);
#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
#endif
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
extern void bio_flush_dcache_pages(struct bio *bi);
#else
static inline void bio_flush_dcache_pages(struct bio *bi)
{
}
#endif
extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
struct bio *src, struct bvec_iter *src_iter);
extern void bio_copy_data(struct bio *dst, struct bio *src);
extern void bio_list_copy_data(struct bio *dst, struct bio *src);
extern void bio_free_pages(struct bio *bio);
extern struct bio *bio_copy_user_iov(struct request_queue *,
struct rq_map_data *,
struct iov_iter *,
gfp_t);
extern int bio_uncopy_user(struct bio *);
void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);
static inline void zero_fill_bio(struct bio *bio)
{
zero_fill_bio_iter(bio, bio->bi_iter);
}
extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
extern unsigned int bvec_nr_vecs(unsigned short idx);
extern const char *bio_devname(struct bio *bio, char *buffer);
#define bio_set_dev(bio, bdev) \
do { \
if ((bio)->bi_disk != (bdev)->bd_disk) \
bio_clear_flag(bio, BIO_THROTTLED);\
(bio)->bi_disk = (bdev)->bd_disk; \
(bio)->bi_partno = (bdev)->bd_partno; \
bio_associate_blkg(bio); \
} while (0)
#define bio_copy_dev(dst, src) \
do { \
(dst)->bi_disk = (src)->bi_disk; \
(dst)->bi_partno = (src)->bi_partno; \
bio_clone_blkg_association(dst, src); \
} while (0)
#define bio_dev(bio) \
disk_devt((bio)->bi_disk)
#if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
void bio_associate_blkg_from_page(struct bio *bio, struct page *page);
#else
static inline void bio_associate_blkg_from_page(struct bio *bio,
struct page *page) { }
#endif
#ifdef CONFIG_BLK_CGROUP
void bio_disassociate_blkg(struct bio *bio);
void bio_associate_blkg(struct bio *bio);
void bio_associate_blkg_from_css(struct bio *bio,
struct cgroup_subsys_state *css);
void bio_clone_blkg_association(struct bio *dst, struct bio *src);
#else /* CONFIG_BLK_CGROUP */
static inline void bio_disassociate_blkg(struct bio *bio) { }
static inline void bio_associate_blkg(struct bio *bio) { }
static inline void bio_associate_blkg_from_css(struct bio *bio,
struct cgroup_subsys_state *css)
{ }
static inline void bio_clone_blkg_association(struct bio *dst,
struct bio *src) { }
#endif /* CONFIG_BLK_CGROUP */
#ifdef CONFIG_HIGHMEM
/*
* remember never ever reenable interrupts between a bvec_kmap_irq and
* bvec_kunmap_irq!
*/
static 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);
BUG_ON(addr & ~PAGE_MASK);
return (char *) addr + bvec->bv_offset;
}
static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
{
unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
kunmap_atomic((void *) ptr);
local_irq_restore(*flags);
}
#else
static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
{
return page_address(bvec->bv_page) + bvec->bv_offset;
}
static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
{
*flags = 0;
}
#endif
/*
* BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
*
* A bio_list anchors a singly-linked list of bios chained through the bi_next
* member of the bio. The bio_list also caches the last list member to allow
* fast access to the tail.
*/
struct bio_list {
struct bio *head;
struct bio *tail;
};
static inline int bio_list_empty(const struct bio_list *bl)
{
return bl->head == NULL;
}
static inline void bio_list_init(struct bio_list *bl)
{
bl->head = bl->tail = NULL;
}
#define BIO_EMPTY_LIST { NULL, NULL }
#define bio_list_for_each(bio, bl) \
for (bio = (bl)->head; bio; bio = bio->bi_next)
static inline unsigned bio_list_size(const struct bio_list *bl)
{
unsigned sz = 0;
struct bio *bio;
bio_list_for_each(bio, bl)
sz++;
return sz;
}
static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
{
bio->bi_next = NULL;
if (bl->tail)
bl->tail->bi_next = bio;
else
bl->head = bio;
bl->tail = bio;
}
static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
{
bio->bi_next = bl->head;
bl->head = bio;
if (!bl->tail)
bl->tail = bio;
}
static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
{
if (!bl2->head)
return;
if (bl->tail)
bl->tail->bi_next = bl2->head;
else
bl->head = bl2->head;
bl->tail = bl2->tail;
}
static inline void bio_list_merge_head(struct bio_list *bl,
struct bio_list *bl2)
{
if (!bl2->head)
return;
if (bl->head)
bl2->tail->bi_next = bl->head;
else
bl->tail = bl2->tail;
bl->head = bl2->head;
}
static inline struct bio *bio_list_peek(struct bio_list *bl)
{
return bl->head;
}
static inline struct bio *bio_list_pop(struct bio_list *bl)
{
struct bio *bio = bl->head;
if (bio) {
bl->head = bl->head->bi_next;
if (!bl->head)
bl->tail = NULL;
bio->bi_next = NULL;
}
return bio;
}
static inline struct bio *bio_list_get(struct bio_list *bl)
{
struct bio *bio = bl->head;
bl->head = bl->tail = NULL;
return bio;
}
/*
* Increment chain count for the bio. Make sure the CHAIN flag update
* is visible before the raised count.
*/
static inline void bio_inc_remaining(struct bio *bio)
{
bio_set_flag(bio, BIO_CHAIN);
smp_mb__before_atomic();
atomic_inc(&bio->__bi_remaining);
}
/*
* 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
struct bio_set {
struct kmem_cache *bio_slab;
unsigned int front_pad;
mempool_t bio_pool;
mempool_t bvec_pool;
#if defined(CONFIG_BLK_DEV_INTEGRITY)
mempool_t bio_integrity_pool;
mempool_t bvec_integrity_pool;
#endif
/*
* Deadlock avoidance for stacking block drivers: see comments in
* bio_alloc_bioset() for details
*/
spinlock_t rescue_lock;
struct bio_list rescue_list;
struct work_struct rescue_work;
struct workqueue_struct *rescue_workqueue;
};
struct biovec_slab {
int nr_vecs;
char *name;
struct kmem_cache *slab;
};
static inline bool bioset_initialized(struct bio_set *bs)
{
return bs->bio_slab != NULL;
}
/*
* a small number of entries is fine, not going to be performance critical.
* basically we just need to survive
*/
#define BIO_SPLIT_ENTRIES 2
#if defined(CONFIG_BLK_DEV_INTEGRITY)
#define bip_for_each_vec(bvl, bip, iter) \
for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
for_each_bio(_bio) \
bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
extern bool bio_integrity_prep(struct bio *);
extern void bio_integrity_advance(struct bio *, unsigned int);
extern void bio_integrity_trim(struct bio *);
extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
extern int bioset_integrity_create(struct bio_set *, int);
extern void bioset_integrity_free(struct bio_set *);
extern void bio_integrity_init(void);
#else /* CONFIG_BLK_DEV_INTEGRITY */
static inline void *bio_integrity(struct bio *bio)
{
return NULL;
}
static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
{
return 0;
}
static inline void bioset_integrity_free (struct bio_set *bs)
{
return;
}
static inline bool bio_integrity_prep(struct bio *bio)
{
return true;
}
static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
gfp_t gfp_mask)
{
return 0;
}
static inline void bio_integrity_advance(struct bio *bio,
unsigned int bytes_done)
{
return;
}
static inline void bio_integrity_trim(struct bio *bio)
{
return;
}
static inline void bio_integrity_init(void)
{
return;
}
static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
{
return false;
}
static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
unsigned int nr)
{
return ERR_PTR(-EINVAL);
}
static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
unsigned int len, unsigned int offset)
{
return 0;
}
#endif /* CONFIG_BLK_DEV_INTEGRITY */
/*
* Mark a bio as polled. Note that for async polled IO, the caller must
* expect -EWOULDBLOCK if we cannot allocate a request (or other resources).
* We cannot block waiting for requests on polled IO, as those completions
* must be found by the caller. This is different than IRQ driven IO, where
* it's safe to wait for IO to complete.
*/
static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb)
{
bio->bi_opf |= REQ_HIPRI;
if (!is_sync_kiocb(kiocb))
bio->bi_opf |= REQ_NOWAIT;
}
#endif /* CONFIG_BLOCK */
#endif /* __LINUX_BIO_H */