From d3b404396977fde1daca3fb4fd4d3b01a3749093 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 18 Oct 2019 16:42:24 -0700 Subject: 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: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/iomap/buffered-io.c | 33 ++++++++++++++++----------------- 1 file changed, 16 insertions(+), 17 deletions(-) (limited to 'fs/iomap') diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 30df87ac8349..7e9d7fdaae49 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -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 -- cgit v1.2.3-59-g8ed1b