block: use iomap for writes to block devices

Use iomap in buffer_head compat mode to write to block devices.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230801172201.1923299-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2023-08-01 19:22:00 +02:00 committed by Jens Axboe
parent a05f7bd957
commit 487c607df7
2 changed files with 30 additions and 2 deletions

View File

@ -5,6 +5,7 @@
menuconfig BLOCK
bool "Enable the block layer" if EXPERT
default y
select FS_IOMAP
select SBITMAP
help
Provide block layer support for the kernel.

View File

@ -15,6 +15,7 @@
#include <linux/falloc.h>
#include <linux/suspend.h>
#include <linux/fs.h>
#include <linux/iomap.h>
#include <linux/module.h>
#include "blk.h"
@ -386,6 +387,27 @@ static ssize_t blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
return __blkdev_direct_IO(iocb, iter, bio_max_segs(nr_pages));
}
static int blkdev_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
unsigned int flags, struct iomap *iomap, struct iomap *srcmap)
{
struct block_device *bdev = I_BDEV(inode);
loff_t isize = i_size_read(inode);
iomap->bdev = bdev;
iomap->offset = ALIGN_DOWN(offset, bdev_logical_block_size(bdev));
if (iomap->offset >= isize)
return -EIO;
iomap->type = IOMAP_MAPPED;
iomap->addr = iomap->offset;
iomap->length = isize - iomap->offset;
iomap->flags |= IOMAP_F_BUFFER_HEAD;
return 0;
}
static const struct iomap_ops blkdev_iomap_ops = {
.iomap_begin = blkdev_iomap_begin,
};
static int blkdev_writepage(struct page *page, struct writeback_control *wbc)
{
return block_write_full_page(page, blkdev_get_block, wbc);
@ -556,6 +578,11 @@ blkdev_direct_write(struct kiocb *iocb, struct iov_iter *from)
return written;
}
static ssize_t blkdev_buffered_write(struct kiocb *iocb, struct iov_iter *from)
{
return iomap_file_buffered_write(iocb, from, &blkdev_iomap_ops);
}
/*
* Write data to the block device. Only intended for the block device itself
* and the raw driver which basically is a fake block device.
@ -605,9 +632,9 @@ static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
ret = blkdev_direct_write(iocb, from);
if (ret >= 0 && iov_iter_count(from))
ret = direct_write_fallback(iocb, from, ret,
generic_perform_write(iocb, from));
blkdev_buffered_write(iocb, from));
} else {
ret = generic_perform_write(iocb, from);
ret = blkdev_buffered_write(iocb, from);
}
if (ret > 0)