diff options
| author | Christoph Hellwig <hch@lst.de> | 2023-01-25 16:34:36 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-02-03 09:33:34 +0300 |
| commit | 3222d8c2a7f888bf38b845b125e9470b12108a4d (patch) | |
| tree | c6a764721e2ae8444f8c4d4a2d784226b7c19d9e /include | |
| parent | 05cda97ecb7046f4192a921741aae33b300dd628 (diff) | |
| download | linux-3222d8c2a7f888bf38b845b125e9470b12108a4d.tar.xz | |
block: remove ->rw_page
The ->rw_page method is a special purpose bypass of the usual bio handling
path that is limited to single-page reads and writes and synchronous which
causes a lot of extra code in the drivers, callers and the block layer.
The only remaining user is the MM swap code. Switch that swap code to
simply submit a single-vec on-stack bio an synchronously wait on it based
on a newly added QUEUE_FLAG_SYNCHRONOUS flag set by the drivers that
currently implement ->rw_page instead. While this touches one extra cache
line and executes extra code, it simplifies the block layer and drivers
and ensures that all feastures are properly supported by all drivers, e.g.
right now ->rw_page bypassed cgroup writeback entirely.
[akpm@linux-foundation.org: fix comment typo, per Dan]
Link: https://lkml.kernel.org/r/20230125133436.447864-8-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/blkdev.h | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 43d4e073b111..c5e59965b145 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -554,6 +554,7 @@ struct request_queue { #define QUEUE_FLAG_IO_STAT 7 /* do disk/partitions IO accounting */ #define QUEUE_FLAG_NOXMERGES 9 /* No extended merges */ #define QUEUE_FLAG_ADD_RANDOM 10 /* Contributes to random pool */ +#define QUEUE_FLAG_SYNCHRONOUS 11 /* always completes in submit context */ #define QUEUE_FLAG_SAME_FORCE 12 /* force complete on same CPU */ #define QUEUE_FLAG_INIT_DONE 14 /* queue is initialized */ #define QUEUE_FLAG_STABLE_WRITES 15 /* don't modify blks until WB is done */ @@ -1250,6 +1251,12 @@ static inline bool bdev_nonrot(struct block_device *bdev) return blk_queue_nonrot(bdev_get_queue(bdev)); } +static inline bool bdev_synchronous(struct block_device *bdev) +{ + return test_bit(QUEUE_FLAG_SYNCHRONOUS, + &bdev_get_queue(bdev)->queue_flags); +} + static inline bool bdev_stable_writes(struct block_device *bdev) { return test_bit(QUEUE_FLAG_STABLE_WRITES, @@ -1382,7 +1389,6 @@ struct block_device_operations { unsigned int flags); int (*open) (struct block_device *, fmode_t); void (*release) (struct gendisk *, fmode_t); - int (*rw_page)(struct block_device *, sector_t, struct page *, enum req_op); int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); unsigned int (*check_events) (struct gendisk *disk, @@ -1417,10 +1423,6 @@ extern int blkdev_compat_ptr_ioctl(struct block_device *, fmode_t, #define blkdev_compat_ptr_ioctl NULL #endif -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 *); - static inline void blk_wake_io_task(struct task_struct *waiter) { /* |