Merge tag 'vfs-6.17-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs iomap updates from Christian Brauner:

 - Refactor the iomap writeback code and split the generic and ioend/bio
   based writeback code.

   There are two methods that define the split between the generic
   writeback code, and the implemementation of it, and all knowledge of
   ioends and bios now sits below that layer.

 - Add fuse iomap support for buffered writes and dirty folio writeback.

   This is needed so that granular uptodate and dirty tracking can be
   used in fuse when large folios are enabled. This has two big
   advantages. For writes, instead of the entire folio needing to be
   read into the page cache, only the relevant portions need to be. For
   writeback, only the dirty portions need to be written back instead of
   the entire folio.

* tag 'vfs-6.17-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fuse: refactor writeback to use iomap_writepage_ctx inode
  fuse: hook into iomap for invalidating and checking partial uptodateness
  fuse: use iomap for folio laundering
  fuse: use iomap for writeback
  fuse: use iomap for buffered writes
  iomap: build the writeback code without CONFIG_BLOCK
  iomap: add read_folio_range() handler for buffered writes
  iomap: improve argument passing to iomap_read_folio_sync
  iomap: replace iomap_folio_ops with iomap_write_ops
  iomap: export iomap_writeback_folio
  iomap: move folio_unlock out of iomap_writeback_folio
  iomap: rename iomap_writepage_map to iomap_writeback_folio
  iomap: move all ioend handling to ioend.c
  iomap: add public helpers for uptodate state manipulation
  iomap: hide ioends from the generic writeback code
  iomap: refactor the writeback interface
  iomap: cleanup the pending writeback tracking in iomap_writepage_map_blocks
  iomap: pass more arguments using the iomap writeback context
  iomap: header diet

1 files changed, 25 insertions, 12 deletions

diff --git a/block/fops.c b/block/fops.c
index 14f706d3af6e..82451ac8ff25 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -540,30 +540,42 @@ static void blkdev_readahead(struct readahead_control *rac)
 	iomap_readahead(rac, &blkdev_iomap_ops);
 }
 
-static int blkdev_map_blocks(struct iomap_writepage_ctx *wpc,
-		struct inode *inode, loff_t offset, unsigned int len)
+static ssize_t blkdev_writeback_range(struct iomap_writepage_ctx *wpc,
+		struct folio *folio, u64 offset, unsigned int len, u64 end_pos)
 {
-	loff_t isize = i_size_read(inode);
+	loff_t isize = i_size_read(wpc->inode);
 
 	if (WARN_ON_ONCE(offset >= isize))
 		return -EIO;
-	if (offset >= wpc->iomap.offset &&
-	    offset < wpc->iomap.offset + wpc->iomap.length)
-		return 0;
-	return blkdev_iomap_begin(inode, offset, isize - offset,
-				  IOMAP_WRITE, &wpc->iomap, NULL);
+
+	if (offset < wpc->iomap.offset ||
+	    offset >= wpc->iomap.offset + wpc->iomap.length) {
+		int error;
+
+		error = blkdev_iomap_begin(wpc->inode, offset, isize - offset,
+				IOMAP_WRITE, &wpc->iomap, NULL);
+		if (error)
+			return error;
+	}
+
+	return iomap_add_to_ioend(wpc, folio, offset, end_pos, len);
 }
 
 static const struct iomap_writeback_ops blkdev_writeback_ops = {
-	.map_blocks		= blkdev_map_blocks,
+	.writeback_range	= blkdev_writeback_range,
+	.writeback_submit	= iomap_ioend_writeback_submit,
 };
 
 static int blkdev_writepages(struct address_space *mapping,
 		struct writeback_control *wbc)
 {
-	struct iomap_writepage_ctx wpc = { };
+	struct iomap_writepage_ctx wpc = {
+		.inode		= mapping->host,
+		.wbc		= wbc,
+		.ops		= &blkdev_writeback_ops
+	};
 
-	return iomap_writepages(mapping, wbc, &wpc, &blkdev_writeback_ops);
+	return iomap_writepages(&wpc);
 }
 
 const struct address_space_operations def_blk_aops = {
@@ -714,7 +726,8 @@ blkdev_direct_write(struct kiocb *iocb, struct iov_iter *from)
 
 static ssize_t blkdev_buffered_write(struct kiocb *iocb, struct iov_iter *from)
 {
-	return iomap_file_buffered_write(iocb, from, &blkdev_iomap_ops, NULL);
+	return iomap_file_buffered_write(iocb, from, &blkdev_iomap_ops, NULL,
+			NULL);
 }
 
 /*