/* SPDX-License-Identifier: GPL-2.0 */ /* * Block data types and constants. Directly include this file only to * break include dependency loop. */ #ifndef __LINUX_BLK_TYPES_H #define __LINUX_BLK_TYPES_H #include <linux/types.h> #include <linux/bvec.h> #include <linux/device.h> #include <linux/ktime.h> #include <linux/rw_hint.h> struct bio_set; struct bio; struct bio_integrity_payload; struct page; struct io_context; struct cgroup_subsys_state; typedef void (bio_end_io_t) (struct bio *); struct bio_crypt_ctx; /* * The basic unit of block I/O is a sector. It is used in a number of contexts * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9 * bytes. Variables of type sector_t represent an offset or size that is a * multiple of 512 bytes. Hence these two constants. */ #ifndef SECTOR_SHIFT #define SECTOR_SHIFT 9 #endif #ifndef SECTOR_SIZE #define SECTOR_SIZE (1 << SECTOR_SHIFT) #endif #define PAGE_SECTORS_SHIFT (PAGE_SHIFT - SECTOR_SHIFT) #define PAGE_SECTORS (1 << PAGE_SECTORS_SHIFT) #define SECTOR_MASK (PAGE_SECTORS - 1) struct block_device { sector_t bd_start_sect; sector_t bd_nr_sectors; struct gendisk * bd_disk; struct request_queue * bd_queue; struct disk_stats __percpu *bd_stats; unsigned long bd_stamp; atomic_t __bd_flags; // partition number + flags #define BD_PARTNO 255 // lower 8 bits; assign-once #define BD_READ_ONLY (1u<<8) // read-only policy #define BD_WRITE_HOLDER (1u<<9) #define BD_HAS_SUBMIT_BIO (1u<<10) #define BD_RO_WARNED (1u<<11) #ifdef CONFIG_FAIL_MAKE_REQUEST #define BD_MAKE_IT_FAIL (1u<<12) #endif dev_t bd_dev; struct address_space *bd_mapping; /* page cache */ atomic_t bd_openers; spinlock_t bd_size_lock; /* for bd_inode->i_size updates */ void * bd_claiming; void * bd_holder; const struct blk_holder_ops *bd_holder_ops; struct mutex bd_holder_lock; int bd_holders; struct kobject *bd_holder_dir; atomic_t bd_fsfreeze_count; /* number of freeze requests */ struct mutex bd_fsfreeze_mutex; /* serialize freeze/thaw */ struct partition_meta_info *bd_meta_info; int bd_writers; #ifdef CONFIG_SECURITY void *bd_security; #endif /* * keep this out-of-line as it's both big and not needed in the fast * path */ struct device bd_device; } __randomize_layout; #define bdev_whole(_bdev) \ ((_bdev)->bd_disk->part0) #define dev_to_bdev(device) \ container_of((device), struct block_device, bd_device) #define bdev_kobj(_bdev) \ (&((_bdev)->bd_device.kobj)) /* * Block error status values. See block/blk-core:blk_errors for the details. */ typedef u8 __bitwise blk_status_t; typedef u16 blk_short_t; #define BLK_STS_OK 0 #define BLK_STS_NOTSUPP ((__force blk_status_t)1) #define BLK_STS_TIMEOUT ((__force blk_status_t)2) #define BLK_STS_NOSPC ((__force blk_status_t)3) #define BLK_STS_TRANSPORT ((__force blk_status_t)4) #define BLK_STS_TARGET ((__force blk_status_t)5) #define BLK_STS_RESV_CONFLICT ((__force blk_status_t)6) #define BLK_STS_MEDIUM ((__force blk_status_t)7) #define BLK_STS_PROTECTION ((__force blk_status_t)8) #define BLK_STS_RESOURCE ((__force blk_status_t)9) #define BLK_STS_IOERR ((__force blk_status_t)10) /* hack for device mapper, don't use elsewhere: */ #define BLK_STS_DM_REQUEUE ((__force blk_status_t)11) /* * BLK_STS_AGAIN should only be returned if RQF_NOWAIT is set * and the bio would block (cf bio_wouldblock_error()) */ #define BLK_STS_AGAIN ((__force blk_status_t)12) /* * BLK_STS_DEV_RESOURCE is returned from the driver to the block layer if * device related resources are unavailable, but the driver can guarantee * that the queue will be rerun in the future once resources become * available again. This is typically the case for device specific * resources that are consumed for IO. If the driver fails allocating these * resources, we know that inflight (or pending) IO will free these * resource upon completion. * * This is different from BLK_STS_RESOURCE in that it explicitly references * a device specific resource. For resources of wider scope, allocation * failure can happen without having pending IO. This means that we can't * rely on request completions freeing these resources, as IO may not be in * flight. Examples of that are kernel memory allocations, DMA mappings, or * any other system wide resources. */ #define BLK_STS_DEV_RESOURCE ((__force blk_status_t)13) /* * BLK_STS_ZONE_OPEN_RESOURCE is returned from the driver in the completion * path if the device returns a status indicating that too many zone resources * are currently open. The same command should be successful if resubmitted * after the number of open zones decreases below the device's limits, which is * reported in the request_queue's max_open_zones. */ #define BLK_STS_ZONE_OPEN_RESOURCE ((__force blk_status_t)14) /* * BLK_STS_ZONE_ACTIVE_RESOURCE is returned from the driver in the completion * path if the device returns a status indicating that too many zone resources * are currently active. The same command should be successful if resubmitted * after the number of active zones decreases below the device's limits, which * is reported in the request_queue's max_active_zones. */ #define BLK_STS_ZONE_ACTIVE_RESOURCE ((__force blk_status_t)15) /* * BLK_STS_OFFLINE is returned from the driver when the target device is offline * or is being taken offline. This could help differentiate the case where a * device is intentionally being shut down from a real I/O error. */ #define BLK_STS_OFFLINE ((__force blk_status_t)16) /* * BLK_STS_DURATION_LIMIT is returned from the driver when the target device * aborted the command because it exceeded one of its Command Duration Limits. */ #define BLK_STS_DURATION_LIMIT ((__force blk_status_t)17) /* * Invalid size or alignment. */ #define BLK_STS_INVAL ((__force blk_status_t)19) /** * blk_path_error - returns true if error may be path related * @error: status the request was completed with * * Description: * This classifies block error status into non-retryable errors and ones * that may be successful if retried on a failover path. * * Return: * %false - retrying failover path will not help * %true - may succeed if retried */ static inline bool blk_path_error(blk_status_t error) { switch (error) { case BLK_STS_NOTSUPP: case BLK_STS_NOSPC: case BLK_STS_TARGET: case BLK_STS_RESV_CONFLICT: case BLK_STS_MEDIUM: case BLK_STS_PROTECTION: return false; } /* Anything else could be a path failure, so should be retried */ return true; } typedef __u32 __bitwise blk_opf_t; typedef unsigned int blk_qc_t; #define BLK_QC_T_NONE -1U /* * main unit of I/O for the block layer and lower layers (ie drivers and * stacking drivers) */ struct bio { struct bio *bi_next; /* request queue link */ struct block_device *bi_bdev; blk_opf_t bi_opf; /* bottom bits REQ_OP, top bits * req_flags. */ unsigned short bi_flags; /* BIO_* below */ unsigned short bi_ioprio; enum rw_hint bi_write_hint; u8 bi_write_stream; blk_status_t bi_status; /* * The bvec gap bit indicates the lowest set bit in any address offset * between all bi_io_vecs. This field is initialized only after the bio * is split to the hardware limits (see bio_split_io_at()). The value * may be used to consider DMA optimization when performing that * mapping. The value is compared to a power of two mask where the * result depends on any bit set within the mask, so saving the lowest * bit is sufficient to know if any segment gap collides with the mask. */ u8 bi_bvec_gap_bit; atomic_t __bi_remaining; /* The actual vec list, preserved by bio_reset() */ struct bio_vec *bi_io_vec; struct bvec_iter bi_iter; union { /* for polled bios: */ blk_qc_t bi_cookie; /* for plugged zoned writes only: */ unsigned int __bi_nr_segments; }; bio_end_io_t *bi_end_io; void *bi_private; #ifdef CONFIG_BLK_CGROUP /* * Represents the association of the css and request_queue for the bio. * If a bio goes direct to device, it will not have a blkg as it will * not have a request_queue associated with it. The reference is put * on release of the bio. */ struct blkcg_gq *bi_blkg; /* Time that this bio was issued. */ u64 issue_time_ns; #ifdef CONFIG_BLK_CGROUP_IOCOST u64 bi_iocost_cost; #endif #endif #ifdef CONFIG_BLK_INLINE_ENCRYPTION struct bio_crypt_ctx *bi_crypt_context; #endif #if defined(CONFIG_BLK_DEV_INTEGRITY) struct bio_integrity_payload *bi_integrity; /* data integrity */ #endif unsigned short bi_vcnt; /* how many bio_vec's */ /* * Everything starting with bi_max_vecs will be preserved by bio_reset() */ /* * Number of elements in `bi_io_vec` that were allocated for this bio. * Only used by the bio submitter to make `bio_add_page` fail once full * and to free the `bi_io_vec` allocation. Must not be used in drivers * and does not hold a useful value for cloned bios. */ unsigned short bi_max_vecs; atomic_t __bi_cnt; /* pin count */ struct bio_set *bi_pool; }; #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs) #define BIO_MAX_SIZE UINT_MAX /* max value of bi_iter.bi_size */ #define BIO_MAX_SECTORS (BIO_MAX_SIZE >> SECTOR_SHIFT) static inline struct bio_vec *bio_inline_vecs(struct bio *bio) { return (struct bio_vec *)(bio + 1); } /* * bio flags */ enum { BIO_PAGE_PINNED, /* Unpin pages in bio_release_pages() */ BIO_CLONED, /* doesn't own data */ BIO_QUIET, /* Make BIO Quiet */ BIO_CHAIN, /* chained bio, ->bi_remaining in effect */ BIO_REFFED, /* bio has elevated ->bi_cnt */ BIO_BPS_THROTTLED, /* This bio has already been subjected to * throttling rules. Don't do it again. */ BIO_TRACE_COMPLETION, /* bio_endio() should trace the final completion * of this bio. */ BIO_CGROUP_ACCT, /* has been accounted to a cgroup */ BIO_QOS_THROTTLED, /* bio went through rq_qos throttle path */ /* * This bio has completed bps throttling at the single tg granularity, * which is different from BIO_BPS_THROTTLED. When the bio is enqueued * into the sq->queued of the upper tg, or is about to be dispatched, * this flag needs to be cleared. Since blk-throttle and rq_qos are not * on the same hierarchical level, reuse the value. */ BIO_TG_BPS_THROTTLED = BIO_QOS_THROTTLED, BIO_QOS_MERGED, /* but went through rq_qos merge path */ BIO_REMAPPED, BIO_ZONE_WRITE_PLUGGING, /* bio handled through zone write plugging */ BIO_EMULATES_ZONE_APPEND, /* bio emulates a zone append operation */ BIO_FLAG_LAST }; typedef __u32 __bitwise blk_mq_req_flags_t; #define REQ_OP_BITS 8 #define REQ_OP_MASK (__force blk_opf_t)((1 << REQ_OP_BITS) - 1) #define REQ_FLAG_BITS 24 /** * enum req_op - Operations common to the bio and request structures. * We use 8 bits for encoding the operation, and the remaining 24 for flags. * * The least significant bit of the operation number indicates the data * transfer direction: * * - if the least significant bit is set transfers are TO the device * - if the least significant bit is not set transfers are FROM the device * * If a operation does not transfer data the least significant bit has no * meaning. */ enum req_op { /** @REQ_OP_READ: read sectors from the device */ REQ_OP_READ = (__force blk_opf_t)0, /** @REQ_OP_WRITE: write sectors to the device */ REQ_OP_WRITE = (__force blk_opf_t)1, /** @REQ_OP_FLUSH: flush the volatile write cache */ REQ_OP_FLUSH = (__force blk_opf_t)2, /** @REQ_OP_DISCARD: discard sectors */ REQ_OP_DISCARD = (__force blk_opf_t)3, /** @REQ_OP_SECURE_ERASE: securely erase sectors */ REQ_OP_SECURE_ERASE = (__force blk_opf_t)5, /** @REQ_OP_ZONE_APPEND: write data at the current zone write pointer */ REQ_OP_ZONE_APPEND = (__force blk_opf_t)7, /** @REQ_OP_WRITE_ZEROES: write the zero filled sector many times */ REQ_OP_WRITE_ZEROES = (__force blk_opf_t)9, /** @REQ_OP_ZONE_OPEN: Open a zone */ REQ_OP_ZONE_OPEN = (__force blk_opf_t)11, /** @REQ_OP_ZONE_CLOSE: Close a zone */ REQ_OP_ZONE_CLOSE = (__force blk_opf_t)13, /** @REQ_OP_ZONE_FINISH: Transition a zone to full */ REQ_OP_ZONE_FINISH = (__force blk_opf_t)15, /** @REQ_OP_ZONE_RESET: reset a zone write pointer */ REQ_OP_ZONE_RESET = (__force blk_opf_t)17, /** @REQ_OP_ZONE_RESET_ALL: reset all the zone present on the device */ REQ_OP_ZONE_RESET_ALL = (__force blk_opf_t)19, /* Driver private requests */ /* private: */ REQ_OP_DRV_IN = (__force blk_opf_t)34, REQ_OP_DRV_OUT = (__force blk_opf_t)35, REQ_OP_LAST = (__force blk_opf_t)36, }; /* Keep cmd_flag_name[] in sync with the definitions below */ enum req_flag_bits { __REQ_FAILFAST_DEV = /* no driver retries of device errors */ REQ_OP_BITS, __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ __REQ_SYNC, /* request is sync (sync write or read) */ __REQ_META, /* metadata io request */ __REQ_PRIO, /* boost priority in cfq */ __REQ_NOMERGE, /* don't touch this for merging */ __REQ_IDLE, /* anticipate more IO after this one */ __REQ_INTEGRITY, /* I/O includes block integrity payload */ __REQ_FUA, /* forced unit access */ __REQ_PREFLUSH, /* request for cache flush */ __REQ_RAHEAD, /* read ahead, can fail anytime */ __REQ_BACKGROUND, /* background IO */ __REQ_NOWAIT, /* Don't wait if request will block */ __REQ_POLLED, /* caller polls for completion using bio_poll */ __REQ_ALLOC_CACHE, /* allocate IO from cache if available */ __REQ_SWAP, /* swap I/O */ __REQ_DRV, /* for driver use */ __REQ_FS_PRIVATE, /* for file system (submitter) use */ __REQ_ATOMIC, /* for atomic write operations */ /* * Command specific flags, keep last: */ /* for REQ_OP_WRITE_ZEROES: */ __REQ_NOUNMAP, /* do not free blocks when zeroing */ __REQ_NR_BITS, /* stops here */ }; #define REQ_FAILFAST_DEV \ (__force blk_opf_t)(1ULL << __REQ_FAILFAST_DEV) #define REQ_FAILFAST_TRANSPORT \ (__force blk_opf_t)(1ULL << __REQ_FAILFAST_TRANSPORT) #define REQ_FAILFAST_DRIVER \ (__force blk_opf_t)(1ULL << __REQ_FAILFAST_DRIVER) #define REQ_SYNC (__force blk_opf_t)(1ULL << __REQ_SYNC) #define REQ_META (__force blk_opf_t)(1ULL << __REQ_META) #define REQ_PRIO (__force blk_opf_t)(1ULL << __REQ_PRIO) #define REQ_NOMERGE (__force blk_opf_t)(1ULL << __REQ_NOMERGE) #define REQ_IDLE (__force blk_opf_t)(1ULL << __REQ_IDLE) #define REQ_INTEGRITY (__force blk_opf_t)(1ULL << __REQ_INTEGRITY) #define REQ_FUA (__force blk_opf_t)(1ULL << __REQ_FUA) #define REQ_PREFLUSH (__force blk_opf_t)(1ULL << __REQ_PREFLUSH) #define REQ_RAHEAD (__force blk_opf_t)(1ULL << __REQ_RAHEAD) #define REQ_BACKGROUND (__force blk_opf_t)(1ULL << __REQ_BACKGROUND) #define REQ_NOWAIT (__force blk_opf_t)(1ULL << __REQ_NOWAIT) #define REQ_POLLED (__force blk_opf_t)(1ULL << __REQ_POLLED) #define REQ_ALLOC_CACHE (__force blk_opf_t)(1ULL << __REQ_ALLOC_CACHE) #define REQ_SWAP (__force blk_opf_t)(1ULL << __REQ_SWAP) #define REQ_DRV (__force blk_opf_t)(1ULL << __REQ_DRV) #define REQ_FS_PRIVATE (__force blk_opf_t)(1ULL << __REQ_FS_PRIVATE) #define REQ_ATOMIC (__force blk_opf_t)(1ULL << __REQ_ATOMIC) #define REQ_NOUNMAP (__force blk_opf_t)(1ULL << __REQ_NOUNMAP) #define REQ_FAILFAST_MASK \ (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) #define REQ_NOMERGE_FLAGS \ (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA) enum stat_group { STAT_READ, STAT_WRITE, STAT_DISCARD, STAT_FLUSH, NR_STAT_GROUPS }; static inline enum req_op bio_op(const struct bio *bio) { return bio->bi_opf & REQ_OP_MASK; } static inline bool op_is_write(blk_opf_t op) { return !!(op & (__force blk_opf_t)1); } /* * Check if the bio or request is one that needs special treatment in the * flush state machine. */ static inline bool op_is_flush(blk_opf_t op) { return op & (REQ_FUA | REQ_PREFLUSH); } /* * Reads are always treated as synchronous, as are requests with the FUA or * PREFLUSH flag. Other operations may be marked as synchronous using the * REQ_SYNC flag. */ static inline bool op_is_sync(blk_opf_t op) { return (op & REQ_OP_MASK) == REQ_OP_READ || (op & (REQ_SYNC | REQ_FUA | REQ_PREFLUSH)); } static inline bool op_is_discard(blk_opf_t op) { return (op & REQ_OP_MASK) == REQ_OP_DISCARD; } /* * Check if a bio or request operation is a zone management operation. */ static inline bool op_is_zone_mgmt(enum req_op op) { switch (op & REQ_OP_MASK) { case REQ_OP_ZONE_RESET: case REQ_OP_ZONE_RESET_ALL: case REQ_OP_ZONE_OPEN: case REQ_OP_ZONE_CLOSE: case REQ_OP_ZONE_FINISH: return true; default: return false; } } static inline int op_stat_group(enum req_op op) { if (op_is_discard(op)) return STAT_DISCARD; return op_is_write(op); } struct blk_rq_stat { u64 mean; u64 min; u64 max; u32 nr_samples; u64 batch; }; #endif /* __LINUX_BLK_TYPES_H */
