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| author | Christoph Hellwig <hch@lst.de> | 2024-06-17 08:04:40 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2024-06-19 07:58:28 -0600 |
| commit | 1122c0c1cc71f740fa4d5f14f239194e06a1d5e7 (patch) | |
| tree | 690fcda48991904d6916c6f6e0f2205e37511531 /block/blk-flush.c | |
| parent | 70905f8706b62113ae32c8df721384ff6ffb6c6a (diff) | |
| download | lwn-1122c0c1cc71f740fa4d5f14f239194e06a1d5e7.tar.gz lwn-1122c0c1cc71f740fa4d5f14f239194e06a1d5e7.zip | |
block: move cache control settings out of queue->flags
Move the cache control settings into the queue_limits so that the flags
can be set atomically with the device queue frozen.
Add new features and flags field for the driver set flags, and internal
(usually sysfs-controlled) flags in the block layer. Note that we'll
eventually remove enough field from queue_limits to bring it back to the
previous size.
The disable flag is inverted compared to the previous meaning, which
means it now survives a rescan, similar to the max_sectors and
max_discard_sectors user limits.
The FLUSH and FUA flags are now inherited by blk_stack_limits, which
simplified the code in dm a lot, but also causes a slight behavior
change in that dm-switch and dm-unstripe now advertise a write cache
despite setting num_flush_bios to 0. The I/O path will handle this
gracefully, but as far as I can tell the lack of num_flush_bios
and thus flush support is a pre-existing data integrity bug in those
targets that really needs fixing, after which a non-zero num_flush_bios
should be required in dm for targets that map to underlying devices.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-flush.c')
| -rw-r--r-- | block/blk-flush.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/block/blk-flush.c b/block/blk-flush.c index 2234f8b3fc05..30b9d5033a2b 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -381,8 +381,8 @@ static void blk_rq_init_flush(struct request *rq) bool blk_insert_flush(struct request *rq) { struct request_queue *q = rq->q; - unsigned long fflags = q->queue_flags; /* may change, cache */ struct blk_flush_queue *fq = blk_get_flush_queue(q, rq->mq_ctx); + bool supports_fua = q->limits.features & BLK_FEAT_FUA; unsigned int policy = 0; /* FLUSH/FUA request must never be merged */ @@ -394,11 +394,10 @@ bool blk_insert_flush(struct request *rq) /* * Check which flushes we need to sequence for this operation. */ - if (fflags & (1UL << QUEUE_FLAG_WC)) { + if (blk_queue_write_cache(q)) { if (rq->cmd_flags & REQ_PREFLUSH) policy |= REQ_FSEQ_PREFLUSH; - if (!(fflags & (1UL << QUEUE_FLAG_FUA)) && - (rq->cmd_flags & REQ_FUA)) + if ((rq->cmd_flags & REQ_FUA) && !supports_fua) policy |= REQ_FSEQ_POSTFLUSH; } @@ -407,7 +406,7 @@ bool blk_insert_flush(struct request *rq) * REQ_PREFLUSH and FUA for the driver. */ rq->cmd_flags &= ~REQ_PREFLUSH; - if (!(fflags & (1UL << QUEUE_FLAG_FUA))) + if (!supports_fua) rq->cmd_flags &= ~REQ_FUA; /* |