diff options
| author | Minchan Kim <minchan@kernel.org> | 2017-11-16 02:33:00 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-16 03:21:02 +0100 |
| commit | 23c47d2ada9f96731492a67b28c0072715075baa (patch) | |
| tree | dbe8a9322eab448997e27b19b1b39b235eaddd2a /drivers/block/brd.c | |
| parent | zram: set BDI_CAP_STABLE_WRITES once (diff) | |
| download | linux-23c47d2ada9f96731492a67b28c0072715075baa.tar.xz linux-23c47d2ada9f96731492a67b28c0072715075baa.zip | |
bdi: introduce BDI_CAP_SYNCHRONOUS_IO
As discussed at
https://lkml.kernel.org/r/<20170728165604.10455-1-ross.zwisler@linux.intel.com>
someday we will remove rw_page(). If so, we need something to detect
such super-fast storage on which synchronous IO operations like the
current rw_page are always a win.
Introduces BDI_CAP_SYNCHRONOUS_IO to indicate such devices. With it, we
could use various optimization techniques.
Link: http://lkml.kernel.org/r/1505886205-9671-3-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/block/brd.c')
| -rw-r--r-- | drivers/block/brd.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/block/brd.c b/drivers/block/brd.c index c1cf87718c2e..588360d79fca 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -20,6 +20,7 @@ #include <linux/radix-tree.h> #include <linux/fs.h> #include <linux/slab.h> +#include <linux/backing-dev.h> #ifdef CONFIG_BLK_DEV_RAM_DAX #include <linux/pfn_t.h> #include <linux/dax.h> @@ -448,6 +449,7 @@ static struct brd_device *brd_alloc(int i) disk->flags = GENHD_FL_EXT_DEVT; sprintf(disk->disk_name, "ram%d", i); set_capacity(disk, rd_size * 2); + disk->queue->backing_dev_info->capabilities |= BDI_CAP_SYNCHRONOUS_IO; #ifdef CONFIG_BLK_DEV_RAM_DAX queue_flag_set_unlocked(QUEUE_FLAG_DAX, brd->brd_queue); |