diff options
Diffstat (limited to 'kernel/include/linux/blkdev.h')
| -rw-r--r-- | kernel/include/linux/blkdev.h | 1674 |
1 files changed, 1674 insertions, 0 deletions
diff --git a/kernel/include/linux/blkdev.h b/kernel/include/linux/blkdev.h new file mode 100644 index 000000000..37faf63af --- /dev/null +++ b/kernel/include/linux/blkdev.h @@ -0,0 +1,1674 @@ +#ifndef _LINUX_BLKDEV_H +#define _LINUX_BLKDEV_H + +#include <linux/sched.h> + +#ifdef CONFIG_BLOCK + +#include <linux/major.h> +#include <linux/genhd.h> +#include <linux/list.h> +#include <linux/llist.h> +#include <linux/timer.h> +#include <linux/workqueue.h> +#include <linux/pagemap.h> +#include <linux/backing-dev.h> +#include <linux/wait.h> +#include <linux/mempool.h> +#include <linux/bio.h> +#include <linux/stringify.h> +#include <linux/gfp.h> +#include <linux/bsg.h> +#include <linux/smp.h> +#include <linux/rcupdate.h> +#include <linux/percpu-refcount.h> + +#include <asm/scatterlist.h> + +struct module; +struct scsi_ioctl_command; + +struct request_queue; +struct elevator_queue; +struct request_pm_state; +struct blk_trace; +struct request; +struct sg_io_hdr; +struct bsg_job; +struct blkcg_gq; +struct blk_flush_queue; + +#define BLKDEV_MIN_RQ 4 +#define BLKDEV_MAX_RQ 128 /* Default maximum */ + +/* + * Maximum number of blkcg policies allowed to be registered concurrently. + * Defined here to simplify include dependency. + */ +#define BLKCG_MAX_POLS 2 + +struct request; +typedef void (rq_end_io_fn)(struct request *, int); + +#define BLK_RL_SYNCFULL (1U << 0) +#define BLK_RL_ASYNCFULL (1U << 1) + +struct request_list { + struct request_queue *q; /* the queue this rl belongs to */ +#ifdef CONFIG_BLK_CGROUP + struct blkcg_gq *blkg; /* blkg this request pool belongs to */ +#endif + /* + * count[], starved[], and wait[] are indexed by + * BLK_RW_SYNC/BLK_RW_ASYNC + */ + int count[2]; + int starved[2]; + mempool_t *rq_pool; + wait_queue_head_t wait[2]; + unsigned int flags; +}; + +/* + * request command types + */ +enum rq_cmd_type_bits { + REQ_TYPE_FS = 1, /* fs request */ + REQ_TYPE_BLOCK_PC, /* scsi command */ + REQ_TYPE_SENSE, /* sense request */ + REQ_TYPE_PM_SUSPEND, /* suspend request */ + REQ_TYPE_PM_RESUME, /* resume request */ + REQ_TYPE_PM_SHUTDOWN, /* shutdown request */ + REQ_TYPE_SPECIAL, /* driver defined type */ + /* + * for ATA/ATAPI devices. this really doesn't belong here, ide should + * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver + * private REQ_LB opcodes to differentiate what type of request this is + */ + REQ_TYPE_ATA_TASKFILE, + REQ_TYPE_ATA_PC, +}; + +#define BLK_MAX_CDB 16 + +/* + * Try to put the fields that are referenced together in the same cacheline. + * + * If you modify this structure, make sure to update blk_rq_init() and + * especially blk_mq_rq_ctx_init() to take care of the added fields. + */ +struct request { + struct list_head queuelist; + union { + struct call_single_data csd; + struct work_struct work; + unsigned long fifo_time; + }; + + struct request_queue *q; + struct blk_mq_ctx *mq_ctx; + + u64 cmd_flags; + enum rq_cmd_type_bits cmd_type; + unsigned long atomic_flags; + + int cpu; + + /* the following two fields are internal, NEVER access directly */ + unsigned int __data_len; /* total data len */ + sector_t __sector; /* sector cursor */ + + struct bio *bio; + struct bio *biotail; + + /* + * The hash is used inside the scheduler, and killed once the + * request reaches the dispatch list. The ipi_list is only used + * to queue the request for softirq completion, which is long + * after the request has been unhashed (and even removed from + * the dispatch list). + */ + union { + struct hlist_node hash; /* merge hash */ + struct list_head ipi_list; + }; + + /* + * The rb_node is only used inside the io scheduler, requests + * are pruned when moved to the dispatch queue. So let the + * completion_data share space with the rb_node. + */ + union { + struct rb_node rb_node; /* sort/lookup */ + void *completion_data; + }; + + /* + * Three pointers are available for the IO schedulers, if they need + * more they have to dynamically allocate it. Flush requests are + * never put on the IO scheduler. So let the flush fields share + * space with the elevator data. + */ + union { + struct { + struct io_cq *icq; + void *priv[2]; + } elv; + + struct { + unsigned int seq; + struct list_head list; + rq_end_io_fn *saved_end_io; + } flush; + }; + + struct gendisk *rq_disk; + struct hd_struct *part; + unsigned long start_time; +#ifdef CONFIG_BLK_CGROUP + struct request_list *rl; /* rl this rq is alloced from */ + unsigned long long start_time_ns; + unsigned long long io_start_time_ns; /* when passed to hardware */ +#endif + /* Number of scatter-gather DMA addr+len pairs after + * physical address coalescing is performed. + */ + unsigned short nr_phys_segments; +#if defined(CONFIG_BLK_DEV_INTEGRITY) + unsigned short nr_integrity_segments; +#endif + + unsigned short ioprio; + + void *special; /* opaque pointer available for LLD use */ + + int tag; + int errors; + + /* + * when request is used as a packet command carrier + */ + unsigned char __cmd[BLK_MAX_CDB]; + unsigned char *cmd; + unsigned short cmd_len; + + unsigned int extra_len; /* length of alignment and padding */ + unsigned int sense_len; + unsigned int resid_len; /* residual count */ + void *sense; + + unsigned long deadline; + struct list_head timeout_list; + unsigned int timeout; + int retries; + + /* + * completion callback. + */ + rq_end_io_fn *end_io; + void *end_io_data; + + /* for bidi */ + struct request *next_rq; +}; + +static inline unsigned short req_get_ioprio(struct request *req) +{ + return req->ioprio; +} + +/* + * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME + * requests. Some step values could eventually be made generic. + */ +struct request_pm_state +{ + /* PM state machine step value, currently driver specific */ + int pm_step; + /* requested PM state value (S1, S2, S3, S4, ...) */ + u32 pm_state; + void* data; /* for driver use */ +}; + +#include <linux/elevator.h> + +struct blk_queue_ctx; + +typedef void (request_fn_proc) (struct request_queue *q); +typedef void (make_request_fn) (struct request_queue *q, struct bio *bio); +typedef int (prep_rq_fn) (struct request_queue *, struct request *); +typedef void (unprep_rq_fn) (struct request_queue *, struct request *); + +struct bio_vec; +struct bvec_merge_data { + struct block_device *bi_bdev; + sector_t bi_sector; + unsigned bi_size; + unsigned long bi_rw; +}; +typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *, + struct bio_vec *); +typedef void (softirq_done_fn)(struct request *); +typedef int (dma_drain_needed_fn)(struct request *); +typedef int (lld_busy_fn) (struct request_queue *q); +typedef int (bsg_job_fn) (struct bsg_job *); + +enum blk_eh_timer_return { + BLK_EH_NOT_HANDLED, + BLK_EH_HANDLED, + BLK_EH_RESET_TIMER, +}; + +typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); + +enum blk_queue_state { + Queue_down, + Queue_up, +}; + +struct blk_queue_tag { + struct request **tag_index; /* map of busy tags */ + unsigned long *tag_map; /* bit map of free/busy tags */ + int busy; /* current depth */ + int max_depth; /* what we will send to device */ + int real_max_depth; /* what the array can hold */ + atomic_t refcnt; /* map can be shared */ + int alloc_policy; /* tag allocation policy */ + int next_tag; /* next tag */ +}; +#define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */ +#define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */ + +#define BLK_SCSI_MAX_CMDS (256) +#define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) + +struct queue_limits { + unsigned long bounce_pfn; + unsigned long seg_boundary_mask; + + unsigned int max_hw_sectors; + unsigned int chunk_sectors; + unsigned int max_sectors; + unsigned int max_segment_size; + unsigned int physical_block_size; + unsigned int alignment_offset; + unsigned int io_min; + unsigned int io_opt; + unsigned int max_discard_sectors; + unsigned int max_write_same_sectors; + unsigned int discard_granularity; + unsigned int discard_alignment; + + unsigned short logical_block_size; + unsigned short max_segments; + unsigned short max_integrity_segments; + + unsigned char misaligned; + unsigned char discard_misaligned; + unsigned char cluster; + unsigned char discard_zeroes_data; + unsigned char raid_partial_stripes_expensive; +}; + +struct request_queue { + /* + * Together with queue_head for cacheline sharing + */ + struct list_head queue_head; + struct request *last_merge; + struct elevator_queue *elevator; + int nr_rqs[2]; /* # allocated [a]sync rqs */ + int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */ + + /* + * If blkcg is not used, @q->root_rl serves all requests. If blkcg + * is used, root blkg allocates from @q->root_rl and all other + * blkgs from their own blkg->rl. Which one to use should be + * determined using bio_request_list(). + */ + struct request_list root_rl; + + request_fn_proc *request_fn; + make_request_fn *make_request_fn; + prep_rq_fn *prep_rq_fn; + unprep_rq_fn *unprep_rq_fn; + merge_bvec_fn *merge_bvec_fn; + softirq_done_fn *softirq_done_fn; + rq_timed_out_fn *rq_timed_out_fn; + dma_drain_needed_fn *dma_drain_needed; + lld_busy_fn *lld_busy_fn; + + struct blk_mq_ops *mq_ops; + + unsigned int *mq_map; + + /* sw queues */ + struct blk_mq_ctx __percpu *queue_ctx; + unsigned int nr_queues; + + /* hw dispatch queues */ + struct blk_mq_hw_ctx **queue_hw_ctx; + unsigned int nr_hw_queues; + + /* + * Dispatch queue sorting + */ + sector_t end_sector; + struct request *boundary_rq; + + /* + * Delayed queue handling + */ + struct delayed_work delay_work; + + struct backing_dev_info backing_dev_info; + + /* + * The queue owner gets to use this for whatever they like. + * ll_rw_blk doesn't touch it. + */ + void *queuedata; + + /* + * various queue flags, see QUEUE_* below + */ + unsigned long queue_flags; + + /* + * ida allocated id for this queue. Used to index queues from + * ioctx. + */ + int id; + + /* + * queue needs bounce pages for pages above this limit + */ + gfp_t bounce_gfp; + + /* + * protects queue structures from reentrancy. ->__queue_lock should + * _never_ be used directly, it is queue private. always use + * ->queue_lock. + */ + spinlock_t __queue_lock; + spinlock_t *queue_lock; + + /* + * queue kobject + */ + struct kobject kobj; + + /* + * mq queue kobject + */ + struct kobject mq_kobj; + +#ifdef CONFIG_PM + struct device *dev; + int rpm_status; + unsigned int nr_pending; +#endif + + /* + * queue settings + */ + unsigned long nr_requests; /* Max # of requests */ + unsigned int nr_congestion_on; + unsigned int nr_congestion_off; + unsigned int nr_batching; + + unsigned int dma_drain_size; + void *dma_drain_buffer; + unsigned int dma_pad_mask; + unsigned int dma_alignment; + + struct blk_queue_tag *queue_tags; + struct list_head tag_busy_list; + + unsigned int nr_sorted; + unsigned int in_flight[2]; + /* + * Number of active block driver functions for which blk_drain_queue() + * must wait. Must be incremented around functions that unlock the + * queue_lock internally, e.g. scsi_request_fn(). + */ + unsigned int request_fn_active; + + unsigned int rq_timeout; + struct timer_list timeout; + struct list_head timeout_list; + + struct list_head icq_list; +#ifdef CONFIG_BLK_CGROUP + DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); + struct blkcg_gq *root_blkg; + struct list_head blkg_list; +#endif + + struct queue_limits limits; + + /* + * sg stuff + */ + unsigned int sg_timeout; + unsigned int sg_reserved_size; + int node; +#ifdef CONFIG_BLK_DEV_IO_TRACE + struct blk_trace *blk_trace; +#endif + /* + * for flush operations + */ + unsigned int flush_flags; + unsigned int flush_not_queueable:1; + struct blk_flush_queue *fq; + + struct list_head requeue_list; + spinlock_t requeue_lock; + struct work_struct requeue_work; + + struct mutex sysfs_lock; + + int bypass_depth; + int mq_freeze_depth; + +#if defined(CONFIG_BLK_DEV_BSG) + bsg_job_fn *bsg_job_fn; + int bsg_job_size; + struct bsg_class_device bsg_dev; +#endif + +#ifdef CONFIG_BLK_DEV_THROTTLING + /* Throttle data */ + struct throtl_data *td; +#endif + struct rcu_head rcu_head; + struct swait_head mq_freeze_wq; + struct percpu_ref mq_usage_counter; + struct list_head all_q_node; + + struct blk_mq_tag_set *tag_set; + struct list_head tag_set_list; +}; + +#define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ +#define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ +#define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ +#define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ +#define QUEUE_FLAG_DYING 5 /* queue being torn down */ +#define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */ +#define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ +#define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ +#define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ +#define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ +#define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ +#define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ +#define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ +#define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ +#define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ +#define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ +#define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ +#define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */ +#define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ +#define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */ +#define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */ +#define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/ +#define QUEUE_FLAG_SG_GAPS 22 /* queue doesn't support SG gaps */ + +#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ + (1 << QUEUE_FLAG_STACKABLE) | \ + (1 << QUEUE_FLAG_SAME_COMP) | \ + (1 << QUEUE_FLAG_ADD_RANDOM)) + +#define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ + (1 << QUEUE_FLAG_STACKABLE) | \ + (1 << QUEUE_FLAG_SAME_COMP)) + +static inline void queue_lockdep_assert_held(struct request_queue *q) +{ + if (q->queue_lock) + lockdep_assert_held(q->queue_lock); +} + +static inline void queue_flag_set_unlocked(unsigned int flag, + struct request_queue *q) +{ + __set_bit(flag, &q->queue_flags); +} + +static inline int queue_flag_test_and_clear(unsigned int flag, + struct request_queue *q) +{ + queue_lockdep_assert_held(q); + + if (test_bit(flag, &q->queue_flags)) { + __clear_bit(flag, &q->queue_flags); + return 1; + } + + return 0; +} + +static inline int queue_flag_test_and_set(unsigned int flag, + struct request_queue *q) +{ + queue_lockdep_assert_held(q); + + if (!test_bit(flag, &q->queue_flags)) { + __set_bit(flag, &q->queue_flags); + return 0; + } + + return 1; +} + +static inline void queue_flag_set(unsigned int flag, struct request_queue *q) +{ + queue_lockdep_assert_held(q); + __set_bit(flag, &q->queue_flags); +} + +static inline void queue_flag_clear_unlocked(unsigned int flag, + struct request_queue *q) +{ + __clear_bit(flag, &q->queue_flags); +} + +static inline int queue_in_flight(struct request_queue *q) +{ + return q->in_flight[0] + q->in_flight[1]; +} + +static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) +{ + queue_lockdep_assert_held(q); + __clear_bit(flag, &q->queue_flags); +} + +#define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) +#define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) +#define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags) +#define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) +#define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags) +#define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags) +#define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) +#define blk_queue_noxmerges(q) \ + test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) +#define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) +#define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) +#define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) +#define blk_queue_stackable(q) \ + test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) +#define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) +#define blk_queue_secdiscard(q) (blk_queue_discard(q) && \ + test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags)) + +#define blk_noretry_request(rq) \ + ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ + REQ_FAILFAST_DRIVER)) + +#define blk_account_rq(rq) \ + (((rq)->cmd_flags & REQ_STARTED) && \ + ((rq)->cmd_type == REQ_TYPE_FS)) + +#define blk_pm_request(rq) \ + ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \ + (rq)->cmd_type == REQ_TYPE_PM_RESUME) + +#define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) +#define blk_bidi_rq(rq) ((rq)->next_rq != NULL) +/* rq->queuelist of dequeued request must be list_empty() */ +#define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) + +#define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) + +#define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0) + +/* + * Driver can handle struct request, if it either has an old style + * request_fn defined, or is blk-mq based. + */ +static inline bool queue_is_rq_based(struct request_queue *q) +{ + return q->request_fn || q->mq_ops; +} + +static inline unsigned int blk_queue_cluster(struct request_queue *q) +{ + return q->limits.cluster; +} + +/* + * We regard a request as sync, if either a read or a sync write + */ +static inline bool rw_is_sync(unsigned int rw_flags) +{ + return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC); +} + +static inline bool rq_is_sync(struct request *rq) +{ + return rw_is_sync(rq->cmd_flags); +} + +static inline bool blk_rl_full(struct request_list *rl, bool sync) +{ + unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; + + return rl->flags & flag; +} + +static inline void blk_set_rl_full(struct request_list *rl, bool sync) +{ + unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; + + rl->flags |= flag; +} + +static inline void blk_clear_rl_full(struct request_list *rl, bool sync) +{ + unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; + + rl->flags &= ~flag; +} + +static inline bool rq_mergeable(struct request *rq) +{ + if (rq->cmd_type != REQ_TYPE_FS) + return false; + + if (rq->cmd_flags & REQ_NOMERGE_FLAGS) + return false; + + return true; +} + +static inline bool blk_check_merge_flags(unsigned int flags1, + unsigned int flags2) +{ + if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD)) + return false; + + if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE)) + return false; + + if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME)) + return false; + + return true; +} + +static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b) +{ + if (bio_data(a) == bio_data(b)) + return true; + + return false; +} + +/* + * q->prep_rq_fn return values + */ +#define BLKPREP_OK 0 /* serve it */ +#define BLKPREP_KILL 1 /* fatal error, kill */ +#define BLKPREP_DEFER 2 /* leave on queue */ + +extern unsigned long blk_max_low_pfn, blk_max_pfn; + +/* + * standard bounce addresses: + * + * BLK_BOUNCE_HIGH : bounce all highmem pages + * BLK_BOUNCE_ANY : don't bounce anything + * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary + */ + +#if BITS_PER_LONG == 32 +#define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) +#else +#define BLK_BOUNCE_HIGH -1ULL +#endif +#define BLK_BOUNCE_ANY (-1ULL) +#define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) + +/* + * default timeout for SG_IO if none specified + */ +#define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) +#define BLK_MIN_SG_TIMEOUT (7 * HZ) + +#ifdef CONFIG_BOUNCE +extern int init_emergency_isa_pool(void); +extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); +#else +static inline int init_emergency_isa_pool(void) +{ + return 0; +} +static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) +{ +} +#endif /* CONFIG_MMU */ + +struct rq_map_data { + struct page **pages; + int page_order; + int nr_entries; + unsigned long offset; + int null_mapped; + int from_user; +}; + +struct req_iterator { + struct bvec_iter iter; + struct bio *bio; +}; + +/* This should not be used directly - use rq_for_each_segment */ +#define for_each_bio(_bio) \ + for (; _bio; _bio = _bio->bi_next) +#define __rq_for_each_bio(_bio, rq) \ + if ((rq->bio)) \ + for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) + +#define rq_for_each_segment(bvl, _rq, _iter) \ + __rq_for_each_bio(_iter.bio, _rq) \ + bio_for_each_segment(bvl, _iter.bio, _iter.iter) + +#define rq_iter_last(bvec, _iter) \ + (_iter.bio->bi_next == NULL && \ + bio_iter_last(bvec, _iter.iter)) + +#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 rq_flush_dcache_pages(struct request *rq); +#else +static inline void rq_flush_dcache_pages(struct request *rq) +{ +} +#endif + +extern int blk_register_queue(struct gendisk *disk); +extern void blk_unregister_queue(struct gendisk *disk); +extern void generic_make_request(struct bio *bio); +extern void blk_rq_init(struct request_queue *q, struct request *rq); +extern void blk_put_request(struct request *); +extern void __blk_put_request(struct request_queue *, struct request *); +extern struct request *blk_get_request(struct request_queue *, int, gfp_t); +extern struct request *blk_make_request(struct request_queue *, struct bio *, + gfp_t); +extern void blk_rq_set_block_pc(struct request *); +extern void blk_requeue_request(struct request_queue *, struct request *); +extern void blk_add_request_payload(struct request *rq, struct page *page, + unsigned int len); +extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); +extern int blk_lld_busy(struct request_queue *q); +extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, + struct bio_set *bs, gfp_t gfp_mask, + int (*bio_ctr)(struct bio *, struct bio *, void *), + void *data); +extern void blk_rq_unprep_clone(struct request *rq); +extern int blk_insert_cloned_request(struct request_queue *q, + struct request *rq); +extern void blk_delay_queue(struct request_queue *, unsigned long); +extern void blk_recount_segments(struct request_queue *, struct bio *); +extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); +extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, + unsigned int, void __user *); +extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, + unsigned int, void __user *); +extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, + struct scsi_ioctl_command __user *); + +/* + * A queue has just exitted congestion. Note this in the global counter of + * congested queues, and wake up anyone who was waiting for requests to be + * put back. + */ +static inline void blk_clear_queue_congested(struct request_queue *q, int sync) +{ + clear_bdi_congested(&q->backing_dev_info, sync); +} + +/* + * A queue has just entered congestion. Flag that in the queue's VM-visible + * state flags and increment the global gounter of congested queues. + */ +static inline void blk_set_queue_congested(struct request_queue *q, int sync) +{ + set_bdi_congested(&q->backing_dev_info, sync); +} + +extern void blk_start_queue(struct request_queue *q); +extern void blk_stop_queue(struct request_queue *q); +extern void blk_sync_queue(struct request_queue *q); +extern void __blk_stop_queue(struct request_queue *q); +extern void __blk_run_queue(struct request_queue *q); +extern void blk_run_queue(struct request_queue *); +extern void blk_run_queue_async(struct request_queue *q); +extern int blk_rq_map_user(struct request_queue *, struct request *, + struct rq_map_data *, void __user *, unsigned long, + gfp_t); +extern int blk_rq_unmap_user(struct bio *); +extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); +extern int blk_rq_map_user_iov(struct request_queue *, struct request *, + struct rq_map_data *, const struct iov_iter *, + gfp_t); +extern int blk_execute_rq(struct request_queue *, struct gendisk *, + struct request *, int); +extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, + struct request *, int, rq_end_io_fn *); + +static inline struct request_queue *bdev_get_queue(struct block_device *bdev) +{ + return bdev->bd_disk->queue; /* this is never NULL */ +} + +/* + * blk_rq_pos() : the current sector + * blk_rq_bytes() : bytes left in the entire request + * blk_rq_cur_bytes() : bytes left in the current segment + * blk_rq_err_bytes() : bytes left till the next error boundary + * blk_rq_sectors() : sectors left in the entire request + * blk_rq_cur_sectors() : sectors left in the current segment + */ +static inline sector_t blk_rq_pos(const struct request *rq) +{ + return rq->__sector; +} + +static inline unsigned int blk_rq_bytes(const struct request *rq) +{ + return rq->__data_len; +} + +static inline int blk_rq_cur_bytes(const struct request *rq) +{ + return rq->bio ? bio_cur_bytes(rq->bio) : 0; +} + +extern unsigned int blk_rq_err_bytes(const struct request *rq); + +static inline unsigned int blk_rq_sectors(const struct request *rq) +{ + return blk_rq_bytes(rq) >> 9; +} + +static inline unsigned int blk_rq_cur_sectors(const struct request *rq) +{ + return blk_rq_cur_bytes(rq) >> 9; +} + +static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q, + unsigned int cmd_flags) +{ + if (unlikely(cmd_flags & REQ_DISCARD)) + return min(q->limits.max_discard_sectors, UINT_MAX >> 9); + + if (unlikely(cmd_flags & REQ_WRITE_SAME)) + return q->limits.max_write_same_sectors; + + return q->limits.max_sectors; +} + +/* + * Return maximum size of a request at given offset. Only valid for + * file system requests. + */ +static inline unsigned int blk_max_size_offset(struct request_queue *q, + sector_t offset) +{ + if (!q->limits.chunk_sectors) + return q->limits.max_sectors; + + return q->limits.chunk_sectors - + (offset & (q->limits.chunk_sectors - 1)); +} + +static inline unsigned int blk_rq_get_max_sectors(struct request *rq) +{ + struct request_queue *q = rq->q; + + if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC)) + return q->limits.max_hw_sectors; + + if (!q->limits.chunk_sectors) + return blk_queue_get_max_sectors(q, rq->cmd_flags); + + return min(blk_max_size_offset(q, blk_rq_pos(rq)), + blk_queue_get_max_sectors(q, rq->cmd_flags)); +} + +static inline unsigned int blk_rq_count_bios(struct request *rq) +{ + unsigned int nr_bios = 0; + struct bio *bio; + + __rq_for_each_bio(bio, rq) + nr_bios++; + + return nr_bios; +} + +/* + * Request issue related functions. + */ +extern struct request *blk_peek_request(struct request_queue *q); +extern void blk_start_request(struct request *rq); +extern struct request *blk_fetch_request(struct request_queue *q); + +/* + * Request completion related functions. + * + * blk_update_request() completes given number of bytes and updates + * the request without completing it. + * + * blk_end_request() and friends. __blk_end_request() must be called + * with the request queue spinlock acquired. + * + * Several drivers define their own end_request and call + * blk_end_request() for parts of the original function. + * This prevents code duplication in drivers. + */ +extern bool blk_update_request(struct request *rq, int error, + unsigned int nr_bytes); +extern void blk_finish_request(struct request *rq, int error); +extern bool blk_end_request(struct request *rq, int error, + unsigned int nr_bytes); +extern void blk_end_request_all(struct request *rq, int error); +extern bool blk_end_request_cur(struct request *rq, int error); +extern bool blk_end_request_err(struct request *rq, int error); +extern bool __blk_end_request(struct request *rq, int error, + unsigned int nr_bytes); +extern void __blk_end_request_all(struct request *rq, int error); +extern bool __blk_end_request_cur(struct request *rq, int error); +extern bool __blk_end_request_err(struct request *rq, int error); + +extern void blk_complete_request(struct request *); +extern void __blk_complete_request(struct request *); +extern void blk_abort_request(struct request *); +extern void blk_unprep_request(struct request *); + +/* + * Access functions for manipulating queue properties + */ +extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, + spinlock_t *lock, int node_id); +extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); +extern struct request_queue *blk_init_allocated_queue(struct request_queue *, + request_fn_proc *, spinlock_t *); +extern void blk_cleanup_queue(struct request_queue *); +extern void blk_queue_make_request(struct request_queue *, make_request_fn *); +extern void blk_queue_bounce_limit(struct request_queue *, u64); +extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int); +extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); +extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int); +extern void blk_queue_max_segments(struct request_queue *, unsigned short); +extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); +extern void blk_queue_max_discard_sectors(struct request_queue *q, + unsigned int max_discard_sectors); +extern void blk_queue_max_write_same_sectors(struct request_queue *q, + unsigned int max_write_same_sectors); +extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); +extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); +extern void blk_queue_alignment_offset(struct request_queue *q, + unsigned int alignment); +extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); +extern void blk_queue_io_min(struct request_queue *q, unsigned int min); +extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); +extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); +extern void blk_set_default_limits(struct queue_limits *lim); +extern void blk_set_stacking_limits(struct queue_limits *lim); +extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, + sector_t offset); +extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, + sector_t offset); +extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, + sector_t offset); +extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); +extern void blk_queue_dma_pad(struct request_queue *, unsigned int); +extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); +extern int blk_queue_dma_drain(struct request_queue *q, + dma_drain_needed_fn *dma_drain_needed, + void *buf, unsigned int size); +extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); +extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); +extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); +extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); +extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); +extern void blk_queue_dma_alignment(struct request_queue *, int); +extern void blk_queue_update_dma_alignment(struct request_queue *, int); +extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); +extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); +extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); +extern void blk_queue_flush(struct request_queue *q, unsigned int flush); +extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); +extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); + +extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); +extern void blk_dump_rq_flags(struct request *, char *); +extern long nr_blockdev_pages(void); + +bool __must_check blk_get_queue(struct request_queue *); +struct request_queue *blk_alloc_queue(gfp_t); +struct request_queue *blk_alloc_queue_node(gfp_t, int); +extern void blk_put_queue(struct request_queue *); + +/* + * block layer runtime pm functions + */ +#ifdef CONFIG_PM +extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev); +extern int blk_pre_runtime_suspend(struct request_queue *q); +extern void blk_post_runtime_suspend(struct request_queue *q, int err); +extern void blk_pre_runtime_resume(struct request_queue *q); +extern void blk_post_runtime_resume(struct request_queue *q, int err); +#else +static inline void blk_pm_runtime_init(struct request_queue *q, + struct device *dev) {} +static inline int blk_pre_runtime_suspend(struct request_queue *q) +{ + return -ENOSYS; +} +static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {} +static inline void blk_pre_runtime_resume(struct request_queue *q) {} +static inline void blk_post_runtime_resume(struct request_queue *q, int err) {} +#endif + +/* + * blk_plug permits building a queue of related requests by holding the I/O + * fragments for a short period. This allows merging of sequential requests + * into single larger request. As the requests are moved from a per-task list to + * the device's request_queue in a batch, this results in improved scalability + * as the lock contention for request_queue lock is reduced. + * + * It is ok not to disable preemption when adding the request to the plug list + * or when attempting a merge, because blk_schedule_flush_list() will only flush + * the plug list when the task sleeps by itself. For details, please see + * schedule() where blk_schedule_flush_plug() is called. + */ +struct blk_plug { + struct list_head list; /* requests */ + struct list_head mq_list; /* blk-mq requests */ + struct list_head cb_list; /* md requires an unplug callback */ +}; +#define BLK_MAX_REQUEST_COUNT 16 + +struct blk_plug_cb; +typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool); +struct blk_plug_cb { + struct list_head list; + blk_plug_cb_fn callback; + void *data; +}; +extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, + void *data, int size); +extern void blk_start_plug(struct blk_plug *); +extern void blk_finish_plug(struct blk_plug *); +extern void blk_flush_plug_list(struct blk_plug *, bool); + +static inline void blk_flush_plug(struct task_struct *tsk) +{ + struct blk_plug *plug = tsk->plug; + + if (plug) + blk_flush_plug_list(plug, false); +} + +static inline void blk_schedule_flush_plug(struct task_struct *tsk) +{ + struct blk_plug *plug = tsk->plug; + + if (plug) + blk_flush_plug_list(plug, true); +} + +static inline bool blk_needs_flush_plug(struct task_struct *tsk) +{ + struct blk_plug *plug = tsk->plug; + + return plug && + (!list_empty(&plug->list) || + !list_empty(&plug->mq_list) || + !list_empty(&plug->cb_list)); +} + +/* + * tag stuff + */ +extern int blk_queue_start_tag(struct request_queue *, struct request *); +extern struct request *blk_queue_find_tag(struct request_queue *, int); +extern void blk_queue_end_tag(struct request_queue *, struct request *); +extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int); +extern void blk_queue_free_tags(struct request_queue *); +extern int blk_queue_resize_tags(struct request_queue *, int); +extern void blk_queue_invalidate_tags(struct request_queue *); +extern struct blk_queue_tag *blk_init_tags(int, int); +extern void blk_free_tags(struct blk_queue_tag *); + +static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, + int tag) +{ + if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) + return NULL; + return bqt->tag_index[tag]; +} + +#define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */ + +extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); +extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, + sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); +extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, + sector_t nr_sects, gfp_t gfp_mask, struct page *page); +extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, + sector_t nr_sects, gfp_t gfp_mask, bool discard); +static inline int sb_issue_discard(struct super_block *sb, sector_t block, + sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) +{ + return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), + nr_blocks << (sb->s_blocksize_bits - 9), + gfp_mask, flags); +} +static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, + sector_t nr_blocks, gfp_t gfp_mask) +{ + return blkdev_issue_zeroout(sb->s_bdev, + block << (sb->s_blocksize_bits - 9), + nr_blocks << (sb->s_blocksize_bits - 9), + gfp_mask, true); +} + +extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); + +enum blk_default_limits { + BLK_MAX_SEGMENTS = 128, + BLK_SAFE_MAX_SECTORS = 255, + BLK_MAX_SEGMENT_SIZE = 65536, + BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, +}; + +#define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) + +static inline unsigned long queue_bounce_pfn(struct request_queue *q) +{ + return q->limits.bounce_pfn; +} + +static inline unsigned long queue_segment_boundary(struct request_queue *q) +{ + return q->limits.seg_boundary_mask; +} + +static inline unsigned int queue_max_sectors(struct request_queue *q) +{ + return q->limits.max_sectors; +} + +static inline unsigned int queue_max_hw_sectors(struct request_queue *q) +{ + return q->limits.max_hw_sectors; +} + +static inline unsigned short queue_max_segments(struct request_queue *q) +{ + return q->limits.max_segments; +} + +static inline unsigned int queue_max_segment_size(struct request_queue *q) +{ + return q->limits.max_segment_size; +} + +static inline unsigned short queue_logical_block_size(struct request_queue *q) +{ + int retval = 512; + + if (q && q->limits.logical_block_size) + retval = q->limits.logical_block_size; + + return retval; +} + +static inline unsigned short bdev_logical_block_size(struct block_device *bdev) +{ + return queue_logical_block_size(bdev_get_queue(bdev)); +} + +static inline unsigned int queue_physical_block_size(struct request_queue *q) +{ + return q->limits.physical_block_size; +} + +static inline unsigned int bdev_physical_block_size(struct block_device *bdev) +{ + return queue_physical_block_size(bdev_get_queue(bdev)); +} + +static inline unsigned int queue_io_min(struct request_queue *q) +{ + return q->limits.io_min; +} + +static inline int bdev_io_min(struct block_device *bdev) +{ + return queue_io_min(bdev_get_queue(bdev)); +} + +static inline unsigned int queue_io_opt(struct request_queue *q) +{ + return q->limits.io_opt; +} + +static inline int bdev_io_opt(struct block_device *bdev) +{ + return queue_io_opt(bdev_get_queue(bdev)); +} + +static inline int queue_alignment_offset(struct request_queue *q) +{ + if (q->limits.misaligned) + return -1; + + return q->limits.alignment_offset; +} + +static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) +{ + unsigned int granularity = max(lim->physical_block_size, lim->io_min); + unsigned int alignment = sector_div(sector, granularity >> 9) << 9; + + return (granularity + lim->alignment_offset - alignment) % granularity; +} + +static inline int bdev_alignment_offset(struct block_device *bdev) +{ + struct request_queue *q = bdev_get_queue(bdev); + + if (q->limits.misaligned) + return -1; + + if (bdev != bdev->bd_contains) + return bdev->bd_part->alignment_offset; + + return q->limits.alignment_offset; +} + +static inline int queue_discard_alignment(struct request_queue *q) +{ + if (q->limits.discard_misaligned) + return -1; + + return q->limits.discard_alignment; +} + +static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) +{ + unsigned int alignment, granularity, offset; + + if (!lim->max_discard_sectors) + return 0; + + /* Why are these in bytes, not sectors? */ + alignment = lim->discard_alignment >> 9; + granularity = lim->discard_granularity >> 9; + if (!granularity) + return 0; + + /* Offset of the partition start in 'granularity' sectors */ + offset = sector_div(sector, granularity); + + /* And why do we do this modulus *again* in blkdev_issue_discard()? */ + offset = (granularity + alignment - offset) % granularity; + + /* Turn it back into bytes, gaah */ + return offset << 9; +} + +static inline int bdev_discard_alignment(struct block_device *bdev) +{ + struct request_queue *q = bdev_get_queue(bdev); + + if (bdev != bdev->bd_contains) + return bdev->bd_part->discard_alignment; + + return q->limits.discard_alignment; +} + +static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) +{ + if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) + return 1; + + return 0; +} + +static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) +{ + return queue_discard_zeroes_data(bdev_get_queue(bdev)); +} + +static inline unsigned int bdev_write_same(struct block_device *bdev) +{ + struct request_queue *q = bdev_get_queue(bdev); + + if (q) + return q->limits.max_write_same_sectors; + + return 0; +} + +static inline int queue_dma_alignment(struct request_queue *q) +{ + return q ? q->dma_alignment : 511; +} + +static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, + unsigned int len) +{ + unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; + return !(addr & alignment) && !(len & alignment); +} + +/* assumes size > 256 */ +static inline unsigned int blksize_bits(unsigned int size) +{ + unsigned int bits = 8; + do { + bits++; + size >>= 1; + } while (size > 256); + return bits; +} + +static inline unsigned int block_size(struct block_device *bdev) +{ + return bdev->bd_block_size; +} + +static inline bool queue_flush_queueable(struct request_queue *q) +{ + return !q->flush_not_queueable; +} + +typedef struct {struct page *v;} Sector; + +unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); + +static inline void put_dev_sector(Sector p) +{ + page_cache_release(p.v); +} + +struct work_struct; +int kblockd_schedule_work(struct work_struct *work); +int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay); +int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay); + +#ifdef CONFIG_BLK_CGROUP +/* + * This should not be using sched_clock(). A real patch is in progress + * to fix this up, until that is in place we need to disable preemption + * around sched_clock() in this function and set_io_start_time_ns(). + */ +static inline void set_start_time_ns(struct request *req) +{ + preempt_disable(); + req->start_time_ns = sched_clock(); + preempt_enable(); +} + +static inline void set_io_start_time_ns(struct request *req) +{ + preempt_disable(); + req->io_start_time_ns = sched_clock(); + preempt_enable(); +} + +static inline uint64_t rq_start_time_ns(struct request *req) +{ + return req->start_time_ns; +} + +static inline uint64_t rq_io_start_time_ns(struct request *req) +{ + return req->io_start_time_ns; +} +#else +static inline void set_start_time_ns(struct request *req) {} +static inline void set_io_start_time_ns(struct request *req) {} +static inline uint64_t rq_start_time_ns(struct request *req) +{ + return 0; +} +static inline uint64_t rq_io_start_time_ns(struct request *req) +{ + return 0; +} +#endif + +#define MODULE_ALIAS_BLOCKDEV(major,minor) \ + MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) +#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ + MODULE_ALIAS("block-major-" __stringify(major) "-*") + +#if defined(CONFIG_BLK_DEV_INTEGRITY) + +enum blk_integrity_flags { + BLK_INTEGRITY_VERIFY = 1 << 0, + BLK_INTEGRITY_GENERATE = 1 << 1, + BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2, + BLK_INTEGRITY_IP_CHECKSUM = 1 << 3, +}; + +struct blk_integrity_iter { + void *prot_buf; + void *data_buf; + sector_t seed; + unsigned int data_size; + unsigned short interval; + const char *disk_name; +}; + +typedef int (integrity_processing_fn) (struct blk_integrity_iter *); + +struct blk_integrity { + integrity_processing_fn *generate_fn; + integrity_processing_fn *verify_fn; + + unsigned short flags; + unsigned short tuple_size; + unsigned short interval; + unsigned short tag_size; + + const char *name; + + struct kobject kobj; +}; + +extern bool blk_integrity_is_initialized(struct gendisk *); +extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); +extern void blk_integrity_unregister(struct gendisk *); +extern int blk_integrity_compare(struct gendisk *, struct gendisk *); +extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, + struct scatterlist *); +extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); +extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, + struct request *); +extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, + struct bio *); + +static inline +struct blk_integrity *bdev_get_integrity(struct block_device *bdev) +{ + return bdev->bd_disk->integrity; +} + +static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) +{ + return disk->integrity; +} + +static inline bool blk_integrity_rq(struct request *rq) +{ + return rq->cmd_flags & REQ_INTEGRITY; +} + +static inline void blk_queue_max_integrity_segments(struct request_queue *q, + unsigned int segs) +{ + q->limits.max_integrity_segments = segs; +} + +static inline unsigned short +queue_max_integrity_segments(struct request_queue *q) +{ + return q->limits.max_integrity_segments; +} + +#else /* CONFIG_BLK_DEV_INTEGRITY */ + +struct bio; +struct block_device; +struct gendisk; +struct blk_integrity; + +static inline int blk_integrity_rq(struct request *rq) +{ + return 0; +} +static inline int blk_rq_count_integrity_sg(struct request_queue *q, + struct bio *b) +{ + return 0; +} +static inline int blk_rq_map_integrity_sg(struct request_queue *q, + struct bio *b, + struct scatterlist *s) +{ + return 0; +} +static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) +{ + return NULL; +} +static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) +{ + return NULL; +} +static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) +{ + return 0; +} +static inline int blk_integrity_register(struct gendisk *d, + struct blk_integrity *b) +{ + return 0; +} +static inline void blk_integrity_unregister(struct gendisk *d) +{ +} +static inline void blk_queue_max_integrity_segments(struct request_queue *q, + unsigned int segs) +{ +} +static inline unsigned short queue_max_integrity_segments(struct request_queue *q) +{ + return 0; +} +static inline bool blk_integrity_merge_rq(struct request_queue *rq, + struct request *r1, + struct request *r2) +{ + return true; +} +static inline bool blk_integrity_merge_bio(struct request_queue *rq, + struct request *r, + struct bio *b) +{ + return true; +} +static inline bool blk_integrity_is_initialized(struct gendisk *g) +{ + return 0; +} + +#endif /* CONFIG_BLK_DEV_INTEGRITY */ + +struct block_device_operations { + int (*open) (struct block_device *, fmode_t); + void (*release) (struct gendisk *, fmode_t); + int (*rw_page)(struct block_device *, sector_t, struct page *, int rw); + int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); + int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); + long (*direct_access)(struct block_device *, sector_t, + void **, unsigned long *pfn, long size); + unsigned int (*check_events) (struct gendisk *disk, + unsigned int clearing); + /* ->media_changed() is DEPRECATED, use ->check_events() instead */ + int (*media_changed) (struct gendisk *); + void (*unlock_native_capacity) (struct gendisk *); + int (*revalidate_disk) (struct gendisk *); + int (*getgeo)(struct block_device *, struct hd_geometry *); + /* this callback is with swap_lock and sometimes page table lock held */ + void (*swap_slot_free_notify) (struct block_device *, unsigned long); + struct module *owner; +}; + +extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, + unsigned long); +extern int bdev_read_page(struct block_device *, sector_t, struct page *); +extern int bdev_write_page(struct block_device *, sector_t, struct page *, + struct writeback_control *); +extern long bdev_direct_access(struct block_device *, sector_t, void **addr, + unsigned long *pfn, long size); +#else /* CONFIG_BLOCK */ + +struct block_device; + +/* + * stubs for when the block layer is configured out + */ +#define buffer_heads_over_limit 0 + +static inline long nr_blockdev_pages(void) +{ + return 0; +} + +struct blk_plug { +}; + +static inline void blk_start_plug(struct blk_plug *plug) +{ +} + +static inline void blk_finish_plug(struct blk_plug *plug) +{ +} + +static inline void blk_flush_plug(struct task_struct *task) +{ +} + +static inline void blk_schedule_flush_plug(struct task_struct *task) +{ +} + + +static inline bool blk_needs_flush_plug(struct task_struct *tsk) +{ + return false; +} + +static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, + sector_t *error_sector) +{ + return 0; +} + +#endif /* CONFIG_BLOCK */ + +#endif |