diff mbox series

[5/6] block: use iomap for writes to block devices

Message ID 20230720140452.63817-6-hch@lst.de (mailing list archive)
State New
Headers show
Series [1/6] fs: remove emergency_thaw_bdev | expand

Commit Message

Christoph Hellwig July 20, 2023, 2:04 p.m. UTC 
Use iomap in buffer_head compat mode to write to block devices.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 block/Kconfig |  1 +
 block/fops.c  | 31 +++++++++++++++++++++++++++++--
 2 files changed, 30 insertions(+), 2 deletions(-)

Comments

Hannes Reinecke July 20, 2023, 3:48 p.m. UTC | #1 
On 7/20/23 16:04, Christoph Hellwig wrote:
> Use iomap in buffer_head compat mode to write to block devices.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>   block/Kconfig |  1 +
>   block/fops.c  | 31 +++++++++++++++++++++++++++++--
>   2 files changed, 30 insertions(+), 2 deletions(-)
> 
Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
Luis Chamberlain July 24, 2023, 8:14 p.m. UTC | #2 
On Thu, Jul 20, 2023 at 04:04:51PM +0200, Christoph Hellwig wrote:
> 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>

  Luis
Pankaj Raghav July 27, 2023, 9:14 a.m. UTC | #3 
On Thu, Jul 20, 2023 at 04:04:51PM +0200, Christoph Hellwig wrote:
> Use iomap in buffer_head compat mode to write to block devices.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks good,
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
diff mbox series

Patch

diff --git a/block/Kconfig b/block/Kconfig
index 86122e459fe046..1a13ef0b1ca10c 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -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.
diff --git a/block/fops.c b/block/fops.c
index 0c37c35003c3b7..31d356c83f27a3 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -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 (WARN_ON_ONCE(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);
@@ -555,6 +577,11 @@  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.
@@ -604,9 +631,9 @@  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)