Commit d3b40439 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Darrick J. Wong
Browse files

iomap: move the zeroing case out of iomap_read_page_sync 



That keeps the function a little easier to understand, and easier to
modify for pending enhancements.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
parent 3590c4d8

fs/iomap/buffered-io.c

+16 −17
Original line number Diff line number Diff line
@@ -562,19 +562,12 @@ iomap_write_failed(struct inode *inode, loff_t pos, unsigned len) 
}



static int

iomap_read_page_sync(struct inode *inode, loff_t block_start, struct page *page,

		unsigned poff, unsigned plen, unsigned from, unsigned to,

		struct iomap *iomap)

iomap_read_page_sync(loff_t block_start, struct page *page, unsigned poff,

		unsigned plen, struct iomap *iomap)

{

	struct bio_vec bvec;

	struct bio bio;



	if (iomap_block_needs_zeroing(inode, iomap, block_start)) {

		zero_user_segments(page, poff, from, to, poff + plen);

		iomap_set_range_uptodate(page, poff, plen);

		return 0;

	}



	bio_init(&bio, &bvec, 1);

	bio.bi_opf = REQ_OP_READ;

	bio.bi_iter.bi_sector = iomap_sector(iomap, block_start);
@@ -592,7 +585,7 @@ __iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, 
	loff_t block_start = pos & ~(block_size - 1);

	loff_t block_end = (pos + len + block_size - 1) & ~(block_size - 1);

	unsigned from = offset_in_page(pos), to = from + len, poff, plen;

	int status = 0;

	int status;



	if (PageUptodate(page))

		return 0;
@@ -603,17 +596,23 @@ __iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, 
		if (plen == 0)

			break;



		if ((from > poff && from < poff + plen) ||

		    (to > poff && to < poff + plen)) {

			status = iomap_read_page_sync(inode, block_start, page,

					poff, plen, from, to, iomap);

			if (status)

				break;

		if ((from <= poff || from >= poff + plen) &&

		    (to <= poff || to >= poff + plen))

			continue;



		if (iomap_block_needs_zeroing(inode, iomap, block_start)) {

			zero_user_segments(page, poff, from, to, poff + plen);

			iomap_set_range_uptodate(page, poff, plen);

			continue;

		}



		status = iomap_read_page_sync(block_start, page, poff, plen,

				iomap);

		if (status)

			return status;

	} while ((block_start += plen) < block_end);



	return status;

	return 0;

}



static int

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