Commit a8b456d0 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

bdi: remove BDI_CAP_SYNCHRONOUS_IO 



BDI_CAP_SYNCHRONOUS_IO is only checked in the swap code, and used to
decided if ->rw_page can be used on a block device.  Just check up for
the method instead.  The only complication is that zram needs a second
set of block_device_operations as it can switch between modes that
actually support ->rw_page and those who don't.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent ed7b6b4f

drivers/block/brd.c

+0 −1
Original line number Diff line number Diff line
@@ -403,7 +403,6 @@ 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);

	brd->brd_queue->backing_dev_info->capabilities |= BDI_CAP_SYNCHRONOUS_IO;



	/* Tell the block layer that this is not a rotational device */

	blk_queue_flag_set(QUEUE_FLAG_NONROT, brd->brd_queue);

drivers/block/zram/zram_drv.c

+13 −6
Original line number Diff line number Diff line
@@ -52,6 +52,9 @@ static unsigned int num_devices = 1; 
 */

static size_t huge_class_size;



static const struct block_device_operations zram_devops;

static const struct block_device_operations zram_wb_devops;



static void zram_free_page(struct zram *zram, size_t index);

static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,

				u32 index, int offset, struct bio *bio);
@@ -408,8 +411,7 @@ static void reset_bdev(struct zram *zram) 
	zram->backing_dev = NULL;

	zram->old_block_size = 0;

	zram->bdev = NULL;

	zram->disk->queue->backing_dev_info->capabilities |=

				BDI_CAP_SYNCHRONOUS_IO;

	zram->disk->fops = &zram_devops;

	kvfree(zram->bitmap);

	zram->bitmap = NULL;

}
@@ -529,8 +531,7 @@ static ssize_t backing_dev_store(struct device *dev, 
	 * freely but in fact, IO is going on so finally could cause

	 * use-after-free when the IO is really done.

	 */

	zram->disk->queue->backing_dev_info->capabilities &=

			~BDI_CAP_SYNCHRONOUS_IO;

	zram->disk->fops = &zram_wb_devops;

	up_write(&zram->init_lock);



	pr_info("setup backing device %s\n", file_name);
@@ -1820,6 +1821,13 @@ static const struct block_device_operations zram_devops = { 
	.owner = THIS_MODULE

};



static const struct block_device_operations zram_wb_devops = {

	.open = zram_open,

	.submit_bio = zram_submit_bio,

	.swap_slot_free_notify = zram_slot_free_notify,

	.owner = THIS_MODULE

};



static DEVICE_ATTR_WO(compact);

static DEVICE_ATTR_RW(disksize);

static DEVICE_ATTR_RO(initstate);
@@ -1947,8 +1955,7 @@ static int zram_add(void) 
	if (ZRAM_LOGICAL_BLOCK_SIZE == PAGE_SIZE)

		blk_queue_max_write_zeroes_sectors(zram->disk->queue, UINT_MAX);



	zram->disk->queue->backing_dev_info->capabilities |=

			(BDI_CAP_STABLE_WRITES | BDI_CAP_SYNCHRONOUS_IO);

	zram->disk->queue->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES;

	device_add_disk(NULL, zram->disk, zram_disk_attr_groups);



	strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor));

drivers/nvdimm/btt.c

+0 −2
Original line number Diff line number Diff line
@@ -1537,8 +1537,6 @@ static int btt_blk_init(struct btt *btt) 
	btt->btt_disk->private_data = btt;

	btt->btt_disk->queue = btt->btt_queue;

	btt->btt_disk->flags = GENHD_FL_EXT_DEVT;

	btt->btt_disk->queue->backing_dev_info->capabilities |=

			BDI_CAP_SYNCHRONOUS_IO;



	blk_queue_logical_block_size(btt->btt_queue, btt->sector_size);

	blk_queue_max_hw_sectors(btt->btt_queue, UINT_MAX);

drivers/nvdimm/pmem.c

+0 −1
Original line number Diff line number Diff line
@@ -475,7 +475,6 @@ static int pmem_attach_disk(struct device *dev, 
	disk->queue		= q;

	disk->flags		= GENHD_FL_EXT_DEVT;

	disk->private_data	= pmem;

	disk->queue->backing_dev_info->capabilities |= BDI_CAP_SYNCHRONOUS_IO;

	nvdimm_namespace_disk_name(ndns, disk->disk_name);

	set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)

			/ 512);

include/linux/backing-dev.h

+0 −9
Original line number Diff line number Diff line
@@ -122,9 +122,6 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); 
 * BDI_CAP_NO_WRITEBACK:   Don't write pages back

 * BDI_CAP_NO_ACCT_WB:     Don't automatically account writeback pages

 * BDI_CAP_STRICTLIMIT:    Keep number of dirty pages below bdi threshold.

 *

 * BDI_CAP_SYNCHRONOUS_IO: Device is so fast that asynchronous IO would be

 *			   inefficient.

 */

#define BDI_CAP_NO_ACCT_DIRTY	0x00000001

#define BDI_CAP_NO_WRITEBACK	0x00000002
@@ -132,7 +129,6 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); 
#define BDI_CAP_STABLE_WRITES	0x00000008

#define BDI_CAP_STRICTLIMIT	0x00000010

#define BDI_CAP_CGROUP_WRITEBACK 0x00000020

#define BDI_CAP_SYNCHRONOUS_IO	0x00000040



#define BDI_CAP_NO_ACCT_AND_WRITEBACK \

	(BDI_CAP_NO_WRITEBACK | BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_ACCT_WB)
@@ -174,11 +170,6 @@ static inline int wb_congested(struct bdi_writeback *wb, int cong_bits) 
long congestion_wait(int sync, long timeout);

long wait_iff_congested(int sync, long timeout);



static inline bool bdi_cap_synchronous_io(struct backing_dev_info *bdi)

{

	return bdi->capabilities & BDI_CAP_SYNCHRONOUS_IO;

}



static inline bool bdi_cap_stable_pages_required(struct backing_dev_info *bdi)

{

	return bdi->capabilities & BDI_CAP_STABLE_WRITES;