diff options
| -rw-r--r-- | Documentation/ABI/stable/sysfs-block | 53 | ||||
| -rw-r--r-- | block/blk-core.c | 19 | ||||
| -rw-r--r-- | block/blk-merge.c | 50 | ||||
| -rw-r--r-- | block/blk-settings.c | 88 | ||||
| -rw-r--r-- | block/blk-sysfs.c | 33 | ||||
| -rw-r--r-- | block/blk.h | 3 | ||||
| -rw-r--r-- | include/linux/blk_types.h | 8 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 55 |
8 files changed, 304 insertions, 5 deletions
diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block index 831f19a32e08..cea8856f798d 100644 --- a/Documentation/ABI/stable/sysfs-block +++ b/Documentation/ABI/stable/sysfs-block @@ -21,6 +21,59 @@ Description: device is offset from the internal allocation unit's natural alignment. +What: /sys/block/<disk>/atomic_write_max_bytes +Date: February 2024 +Contact: Himanshu Madhani <himanshu.madhani@oracle.com> +Description: + [RO] This parameter specifies the maximum atomic write + size reported by the device. This parameter is relevant + for merging of writes, where a merged atomic write + operation must not exceed this number of bytes. + This parameter may be greater than the value in + atomic_write_unit_max_bytes as + atomic_write_unit_max_bytes will be rounded down to a + power-of-two and atomic_write_unit_max_bytes may also be + limited by some other queue limits, such as max_segments. + This parameter - along with atomic_write_unit_min_bytes + and atomic_write_unit_max_bytes - will not be larger than + max_hw_sectors_kb, but may be larger than max_sectors_kb. + + +What: /sys/block/<disk>/atomic_write_unit_min_bytes +Date: February 2024 +Contact: Himanshu Madhani <himanshu.madhani@oracle.com> +Description: + [RO] This parameter specifies the smallest block which can + be written atomically with an atomic write operation. All + atomic write operations must begin at a + atomic_write_unit_min boundary and must be multiples of + atomic_write_unit_min. This value must be a power-of-two. + + +What: /sys/block/<disk>/atomic_write_unit_max_bytes +Date: February 2024 +Contact: Himanshu Madhani <himanshu.madhani@oracle.com> +Description: + [RO] This parameter defines the largest block which can be + written atomically with an atomic write operation. This + value must be a multiple of atomic_write_unit_min and must + be a power-of-two. This value will not be larger than + atomic_write_max_bytes. + + +What: /sys/block/<disk>/atomic_write_boundary_bytes +Date: February 2024 +Contact: Himanshu Madhani <himanshu.madhani@oracle.com> +Description: + [RO] A device may need to internally split an atomic write I/O + which straddles a given logical block address boundary. This + parameter specifies the size in bytes of the atomic boundary if + one is reported by the device. This value must be a + power-of-two and at least the size as in + atomic_write_unit_max_bytes. + Any attempt to merge atomic write I/Os must not result in a + merged I/O which crosses this boundary (if any). + What: /sys/block/<disk>/diskseq Date: February 2021 diff --git a/block/blk-core.c b/block/blk-core.c index 8d9fbd353fc7..6fc1a5a1980d 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -174,6 +174,8 @@ static const struct { /* Command duration limit device-side timeout */ [BLK_STS_DURATION_LIMIT] = { -ETIME, "duration limit exceeded" }, + [BLK_STS_INVAL] = { -EINVAL, "invalid" }, + /* everything else not covered above: */ [BLK_STS_IOERR] = { -EIO, "I/O" }, }; @@ -739,6 +741,18 @@ void submit_bio_noacct_nocheck(struct bio *bio) __submit_bio_noacct(bio); } +static blk_status_t blk_validate_atomic_write_op_size(struct request_queue *q, + struct bio *bio) +{ + if (bio->bi_iter.bi_size > queue_atomic_write_unit_max_bytes(q)) + return BLK_STS_INVAL; + + if (bio->bi_iter.bi_size % queue_atomic_write_unit_min_bytes(q)) + return BLK_STS_INVAL; + + return BLK_STS_OK; +} + /** * submit_bio_noacct - re-submit a bio to the block device layer for I/O * @bio: The bio describing the location in memory and on the device. @@ -797,6 +811,11 @@ void submit_bio_noacct(struct bio *bio) switch (bio_op(bio)) { case REQ_OP_READ: case REQ_OP_WRITE: + if (bio->bi_opf & REQ_ATOMIC) { + status = blk_validate_atomic_write_op_size(q, bio); + if (status != BLK_STS_OK) + goto end_io; + } break; case REQ_OP_FLUSH: /* diff --git a/block/blk-merge.c b/block/blk-merge.c index 68969e27c831..cff20bcc0252 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -154,8 +154,16 @@ static struct bio *bio_split_write_zeroes(struct bio *bio, return bio_split(bio, lim->max_write_zeroes_sectors, GFP_NOIO, bs); } -static inline unsigned int blk_boundary_sectors(const struct queue_limits *lim) +static inline unsigned int blk_boundary_sectors(const struct queue_limits *lim, + bool is_atomic) { + /* + * chunk_sectors must be a multiple of atomic_write_boundary_sectors if + * both non-zero. + */ + if (is_atomic && lim->atomic_write_boundary_sectors) + return lim->atomic_write_boundary_sectors; + return lim->chunk_sectors; } @@ -172,8 +180,18 @@ static inline unsigned get_max_io_size(struct bio *bio, { unsigned pbs = lim->physical_block_size >> SECTOR_SHIFT; unsigned lbs = lim->logical_block_size >> SECTOR_SHIFT; - unsigned boundary_sectors = blk_boundary_sectors(lim); - unsigned max_sectors = lim->max_sectors, start, end; + bool is_atomic = bio->bi_opf & REQ_ATOMIC; + unsigned boundary_sectors = blk_boundary_sectors(lim, is_atomic); + unsigned max_sectors, start, end; + + /* + * We ignore lim->max_sectors for atomic writes because it may less + * than the actual bio size, which we cannot tolerate. + */ + if (is_atomic) + max_sectors = lim->atomic_write_max_sectors; + else + max_sectors = lim->max_sectors; if (boundary_sectors) { max_sectors = min(max_sectors, @@ -311,6 +329,11 @@ struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim, *segs = nsegs; return NULL; split: + if (bio->bi_opf & REQ_ATOMIC) { + bio->bi_status = BLK_STS_INVAL; + bio_endio(bio); + return ERR_PTR(-EINVAL); + } /* * We can't sanely support splitting for a REQ_NOWAIT bio. End it * with EAGAIN if splitting is required and return an error pointer. @@ -596,11 +619,12 @@ static inline unsigned int blk_rq_get_max_sectors(struct request *rq, struct request_queue *q = rq->q; struct queue_limits *lim = &q->limits; unsigned int max_sectors, boundary_sectors; + bool is_atomic = rq->cmd_flags & REQ_ATOMIC; if (blk_rq_is_passthrough(rq)) return q->limits.max_hw_sectors; - boundary_sectors = blk_boundary_sectors(lim); + boundary_sectors = blk_boundary_sectors(lim, is_atomic); max_sectors = blk_queue_get_max_sectors(rq); if (!boundary_sectors || @@ -806,6 +830,18 @@ static enum elv_merge blk_try_req_merge(struct request *req, return ELEVATOR_NO_MERGE; } +static bool blk_atomic_write_mergeable_rq_bio(struct request *rq, + struct bio *bio) +{ + return (rq->cmd_flags & REQ_ATOMIC) == (bio->bi_opf & REQ_ATOMIC); +} + +static bool blk_atomic_write_mergeable_rqs(struct request *rq, + struct request *next) +{ + return (rq->cmd_flags & REQ_ATOMIC) == (next->cmd_flags & REQ_ATOMIC); +} + /* * For non-mq, this has to be called with the request spinlock acquired. * For mq with scheduling, the appropriate queue wide lock should be held. @@ -829,6 +865,9 @@ static struct request *attempt_merge(struct request_queue *q, if (req->ioprio != next->ioprio) return NULL; + if (!blk_atomic_write_mergeable_rqs(req, next)) + return NULL; + /* * If we are allowed to merge, then append bio list * from next to rq and release next. merge_requests_fn @@ -960,6 +999,9 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) if (rq->ioprio != bio_prio(bio)) return false; + if (blk_atomic_write_mergeable_rq_bio(rq, bio) == false) + return false; + return true; } diff --git a/block/blk-settings.c b/block/blk-settings.c index b19306804056..37fe4c8f6b6b 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -136,6 +136,92 @@ static int blk_validate_integrity_limits(struct queue_limits *lim) } /* + * Returns max guaranteed bytes which we can fit in a bio. + * + * We request that an atomic_write is ITER_UBUF iov_iter (so a single vector), + * so we assume that we can fit in at least PAGE_SIZE in a segment, apart from + * the first and last segments. + */ +static +unsigned int blk_queue_max_guaranteed_bio(struct queue_limits *lim) +{ + unsigned int max_segments = min(BIO_MAX_VECS, lim->max_segments); + unsigned int length; + + length = min(max_segments, 2) * lim->logical_block_size; + if (max_segments > 2) + length += (max_segments - 2) * PAGE_SIZE; + + return length; +} + +static void blk_atomic_writes_update_limits(struct queue_limits *lim) +{ + unsigned int unit_limit = min(lim->max_hw_sectors << SECTOR_SHIFT, + blk_queue_max_guaranteed_bio(lim)); + + unit_limit = rounddown_pow_of_two(unit_limit); + + lim->atomic_write_max_sectors = + min(lim->atomic_write_hw_max >> SECTOR_SHIFT, + lim->max_hw_sectors); + lim->atomic_write_unit_min = + min(lim->atomic_write_hw_unit_min, unit_limit); + lim->atomic_write_unit_max = + min(lim->atomic_write_hw_unit_max, unit_limit); + lim->atomic_write_boundary_sectors = + lim->atomic_write_hw_boundary >> SECTOR_SHIFT; +} + +static void blk_validate_atomic_write_limits(struct queue_limits *lim) +{ + unsigned int chunk_sectors = lim->chunk_sectors; + unsigned int boundary_sectors; + + if (!lim->atomic_write_hw_max) + goto unsupported; + + boundary_sectors = lim->atomic_write_hw_boundary >> SECTOR_SHIFT; + + if (boundary_sectors) { + /* + * A feature of boundary support is that it disallows bios to + * be merged which would result in a merged request which + * crosses either a chunk sector or atomic write HW boundary, + * even though chunk sectors may be just set for performance. + * For simplicity, disallow atomic writes for a chunk sector + * which is non-zero and smaller than atomic write HW boundary. + * Furthermore, chunk sectors must be a multiple of atomic + * write HW boundary. Otherwise boundary support becomes + * complicated. + * Devices which do not conform to these rules can be dealt + * with if and when they show up. + */ + if (WARN_ON_ONCE(do_div(chunk_sectors, boundary_sectors))) + goto unsupported; + + /* + * The boundary size just needs to be a multiple of unit_max + * (and not necessarily a power-of-2), so this following check + * could be relaxed in future. + * Furthermore, if needed, unit_max could even be reduced so + * that it is compliant with a !power-of-2 boundary. + */ + if (!is_power_of_2(boundary_sectors)) + goto unsupported; + } + + blk_atomic_writes_update_limits(lim); + return; + +unsupported: + lim->atomic_write_max_sectors = 0; + lim->atomic_write_boundary_sectors = 0; + lim->atomic_write_unit_min = 0; + lim->atomic_write_unit_max = 0; +} + +/* * Check that the limits in lim are valid, initialize defaults for unset * values, and cap values based on others where needed. */ @@ -272,6 +358,8 @@ static int blk_validate_limits(struct queue_limits *lim) if (!(lim->features & BLK_FEAT_WRITE_CACHE)) lim->features &= ~BLK_FEAT_FUA; + blk_validate_atomic_write_limits(lim); + err = blk_validate_integrity_limits(lim); if (err) return err; diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 59e6d111ed05..1a984179f3ac 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -118,6 +118,30 @@ static ssize_t queue_max_discard_segments_show(struct request_queue *q, return queue_var_show(queue_max_discard_segments(q), page); } +static ssize_t queue_atomic_write_max_bytes_show(struct request_queue *q, + char *page) +{ + return queue_var_show(queue_atomic_write_max_bytes(q), page); +} + +static ssize_t queue_atomic_write_boundary_show(struct request_queue *q, + char *page) +{ + return queue_var_show(queue_atomic_write_boundary_bytes(q), page); +} + +static ssize_t queue_atomic_write_unit_min_show(struct request_queue *q, + char *page) +{ + return queue_var_show(queue_atomic_write_unit_min_bytes(q), page); +} + +static ssize_t queue_atomic_write_unit_max_show(struct request_queue *q, + char *page) +{ + return queue_var_show(queue_atomic_write_unit_max_bytes(q), page); +} + static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page) { return queue_var_show(q->limits.max_integrity_segments, page); @@ -505,6 +529,11 @@ QUEUE_RO_ENTRY(queue_discard_max_hw, "discard_max_hw_bytes"); QUEUE_RW_ENTRY(queue_discard_max, "discard_max_bytes"); QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data"); +QUEUE_RO_ENTRY(queue_atomic_write_max_bytes, "atomic_write_max_bytes"); +QUEUE_RO_ENTRY(queue_atomic_write_boundary, "atomic_write_boundary_bytes"); +QUEUE_RO_ENTRY(queue_atomic_write_unit_max, "atomic_write_unit_max_bytes"); +QUEUE_RO_ENTRY(queue_atomic_write_unit_min, "atomic_write_unit_min_bytes"); + QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes"); QUEUE_RO_ENTRY(queue_write_zeroes_max, "write_zeroes_max_bytes"); QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes"); @@ -626,6 +655,10 @@ static struct attribute *queue_attrs[] = { &queue_discard_max_entry.attr, &queue_discard_max_hw_entry.attr, &queue_discard_zeroes_data_entry.attr, + &queue_atomic_write_max_bytes_entry.attr, + &queue_atomic_write_boundary_entry.attr, + &queue_atomic_write_unit_min_entry.attr, + &queue_atomic_write_unit_max_entry.attr, &queue_write_same_max_entry.attr, &queue_write_zeroes_max_entry.attr, &queue_zone_append_max_entry.attr, diff --git a/block/blk.h b/block/blk.h index 20c5718815e2..d0a986d8ee50 100644 --- a/block/blk.h +++ b/block/blk.h @@ -194,6 +194,9 @@ static inline unsigned int blk_queue_get_max_sectors(struct request *rq) if (unlikely(op == REQ_OP_WRITE_ZEROES)) return q->limits.max_write_zeroes_sectors; + if (rq->cmd_flags & REQ_ATOMIC) + return q->limits.atomic_write_max_sectors; + return q->limits.max_sectors; } diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 781c4500491b..632edd71f8c6 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -162,6 +162,11 @@ typedef u16 blk_short_t; */ #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 @@ -370,7 +375,7 @@ enum req_flag_bits { __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: */ @@ -402,6 +407,7 @@ enum req_flag_bits { #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) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index fb7d4c21bba8..4816f3b1d528 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -377,6 +377,16 @@ struct queue_limits { unsigned int discard_alignment; unsigned int zone_write_granularity; + /* atomic write limits */ + unsigned int atomic_write_hw_max; + unsigned int atomic_write_max_sectors; + unsigned int atomic_write_hw_boundary; + unsigned int atomic_write_boundary_sectors; + unsigned int atomic_write_hw_unit_min; + unsigned int atomic_write_unit_min; + unsigned int atomic_write_hw_unit_max; + unsigned int atomic_write_unit_max; + unsigned short max_segments; unsigned short max_integrity_segments; unsigned short max_discard_segments; @@ -1403,6 +1413,30 @@ static inline int queue_dma_alignment(const struct request_queue *q) return q ? q->limits.dma_alignment : 511; } +static inline unsigned int +queue_atomic_write_unit_max_bytes(const struct request_queue *q) +{ + return q->limits.atomic_write_unit_max; +} + +static inline unsigned int +queue_atomic_write_unit_min_bytes(const struct request_queue *q) +{ + return q->limits.atomic_write_unit_min; +} + +static inline unsigned int +queue_atomic_write_boundary_bytes(const struct request_queue *q) +{ + return q->limits.atomic_write_boundary_sectors << SECTOR_SHIFT; +} + +static inline unsigned int +queue_atomic_write_max_bytes(const struct request_queue *q) +{ + return q->limits.atomic_write_max_sectors << SECTOR_SHIFT; +} + static inline unsigned int bdev_dma_alignment(struct block_device *bdev) { return queue_dma_alignment(bdev_get_queue(bdev)); @@ -1644,6 +1678,27 @@ struct io_comp_batch { void (*complete)(struct io_comp_batch *); }; +static inline bool bdev_can_atomic_write(struct block_device *bdev) +{ + struct request_queue *bd_queue = bdev->bd_queue; + struct queue_limits *limits = &bd_queue->limits; + + if (!limits->atomic_write_unit_min) + return false; + + if (bdev_is_partition(bdev)) { + sector_t bd_start_sect = bdev->bd_start_sect; + unsigned int alignment = + max(limits->atomic_write_unit_min, + limits->atomic_write_hw_boundary); + + if (!IS_ALIGNED(bd_start_sect, alignment >> SECTOR_SHIFT)) + return false; + } + + return true; +} + #define DEFINE_IO_COMP_BATCH(name) struct io_comp_batch name = { } #endif /* _LINUX_BLKDEV_H */ |