diff options
| author | Christoph Hellwig <hch@lst.de> | 2021-03-31 09:30:00 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-04-06 09:28:17 -0600 |
| commit | 9bb33f24abbd0fa2fadad01ec75438d7cc239189 (patch) | |
| tree | 7c503535797f615db7360dc4aa9081c68bffbded /block/blk.h | |
| parent | ce288e0535688cc3475a3c3d4d96624514c3550c (diff) | |
block: refactor the bounce buffering code
Get rid of all the PFN arithmetics and just use an enum for the two
remaining options, and use PageHighMem for the actual bounce decision.
Add a fast path to entirely avoid the call for the common case of a queue
not using the legacy bouncing code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20210331073001.46776-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk.h')
| -rw-r--r-- | block/blk.h | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/block/blk.h b/block/blk.h index 895c9f4a5182..8f4337c5a9e6 100644 --- a/block/blk.h +++ b/block/blk.h @@ -6,6 +6,7 @@ #include <linux/blk-mq.h> #include <linux/part_stat.h> #include <linux/blk-crypto.h> +#include <linux/memblock.h> /* for max_pfn/max_low_pfn */ #include <xen/xen.h> #include "blk-crypto-internal.h" #include "blk-mq.h" @@ -311,13 +312,20 @@ static inline void blk_throtl_bio_endio(struct bio *bio) { } static inline void blk_throtl_stat_add(struct request *rq, u64 time) { } #endif -#ifdef CONFIG_BOUNCE -extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); -#else +void __blk_queue_bounce(struct request_queue *q, struct bio **bio); + +static inline bool blk_queue_may_bounce(struct request_queue *q) +{ + return IS_ENABLED(CONFIG_BOUNCE) && + q->limits.bounce == BLK_BOUNCE_HIGH && + max_low_pfn >= max_pfn; +} + static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) { + if (unlikely(blk_queue_may_bounce(q) && bio_has_data(*bio))) + __blk_queue_bounce(q, bio); } -#endif /* CONFIG_BOUNCE */ #ifdef CONFIG_BLK_CGROUP_IOLATENCY extern int blk_iolatency_init(struct request_queue *q); |