ext2, ext4, xfs: retrieve dax_device for iomap operations

In preparation for converting fs/dax.c to use dax_direct_access()
instead of bdev_direct_access(), add the plumbing to retrieve the
dax_device associated with a given block_device.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams
2017-01-27 12:04:59 -08:00
parent 817bf40265
commit fa5d932c32
4 changed files with 27 additions and 2 deletions

View File

@@ -3305,6 +3305,7 @@ static int ext4_releasepage(struct page *page, gfp_t wait)
static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
unsigned flags, struct iomap *iomap)
{
struct block_device *bdev;
unsigned int blkbits = inode->i_blkbits;
unsigned long first_block = offset >> blkbits;
unsigned long last_block = (offset + length - 1) >> blkbits;
@@ -3373,7 +3374,12 @@ retry:
}
iomap->flags = 0;
iomap->bdev = inode->i_sb->s_bdev;
bdev = inode->i_sb->s_bdev;
iomap->bdev = bdev;
if (blk_queue_dax(bdev->bd_queue))
iomap->dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
else
iomap->dax_dev = NULL;
iomap->offset = first_block << blkbits;
if (ret == 0) {
@@ -3406,6 +3412,7 @@ static int ext4_iomap_end(struct inode *inode, loff_t offset, loff_t length,
int blkbits = inode->i_blkbits;
bool truncate = false;
put_dax(iomap->dax_dev);
if (!(flags & IOMAP_WRITE) || (flags & IOMAP_FAULT))
return 0;