From b74b1293e6cae70bade491067f15b9d33e040cad Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 10 Aug 2021 18:33:14 -0700 Subject: [PATCH] iomap: rework unshare flag Instead of another internal flags namespace inside of buffered-io.c, just pass a UNSHARE hint in the main iomap flags field. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/iomap/buffered-io.c | 23 +++++++++-------------- include/linux/iomap.h | 1 + 2 files changed, 10 insertions(+), 14 deletions(-) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index d6d1fd0..a0ef7eb 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -508,10 +508,6 @@ iomap_migrate_page(struct address_space *mapping, struct page *newpage, EXPORT_SYMBOL_GPL(iomap_migrate_page); #endif /* CONFIG_MIGRATION */ -enum { - IOMAP_WRITE_F_UNSHARE = (1 << 0), -}; - static void iomap_write_failed(struct inode *inode, loff_t pos, unsigned len) { @@ -541,7 +537,7 @@ iomap_read_page_sync(loff_t block_start, struct page *page, unsigned poff, } static int __iomap_write_begin(struct iomap_iter *iter, loff_t pos, - unsigned len, int flags, struct page *page) + unsigned len, struct page *page) { struct iomap *srcmap = iomap_iter_srcmap(iter); struct iomap_page *iop = iomap_page_create(iter->inode, page); @@ -560,13 +556,13 @@ static int __iomap_write_begin(struct iomap_iter *iter, loff_t pos, if (plen == 0) break; - if (!(flags & IOMAP_WRITE_F_UNSHARE) && + if (!(iter->flags & IOMAP_UNSHARE) && (from <= poff || from >= poff + plen) && (to <= poff || to >= poff + plen)) continue; if (iomap_block_needs_zeroing(iter, block_start)) { - if (WARN_ON_ONCE(flags & IOMAP_WRITE_F_UNSHARE)) + if (WARN_ON_ONCE(iter->flags & IOMAP_UNSHARE)) return -EIO; zero_user_segments(page, poff, from, to, poff + plen); } else { @@ -596,7 +592,7 @@ static int iomap_write_begin_inline(struct iomap_iter *iter, } static int iomap_write_begin(struct iomap_iter *iter, loff_t pos, unsigned len, - unsigned flags, struct page **pagep) + struct page **pagep) { const struct iomap_page_ops *page_ops = iter->iomap.page_ops; struct iomap *srcmap = iomap_iter_srcmap(iter); @@ -628,7 +624,7 @@ static int iomap_write_begin(struct iomap_iter *iter, loff_t pos, unsigned len, else if (srcmap->flags & IOMAP_F_BUFFER_HEAD) status = __block_write_begin_int(page, pos, len, NULL, srcmap); else - status = __iomap_write_begin(iter, pos, len, flags, page); + status = __iomap_write_begin(iter, pos, len, page); if (unlikely(status)) goto out_unlock; @@ -759,7 +755,7 @@ again: break; } - status = iomap_write_begin(iter, pos, bytes, 0, &page); + status = iomap_write_begin(iter, pos, bytes, &page); if (unlikely(status)) break; @@ -836,8 +832,7 @@ static loff_t iomap_unshare_iter(struct iomap_iter *iter) unsigned long bytes = min_t(loff_t, PAGE_SIZE - offset, length); struct page *page; - status = iomap_write_begin(iter, pos, bytes, - IOMAP_WRITE_F_UNSHARE, &page); + status = iomap_write_begin(iter, pos, bytes, &page); if (unlikely(status)) return status; @@ -865,7 +860,7 @@ iomap_file_unshare(struct inode *inode, loff_t pos, loff_t len, .inode = inode, .pos = pos, .len = len, - .flags = IOMAP_WRITE, + .flags = IOMAP_WRITE | IOMAP_UNSHARE, }; int ret; @@ -882,7 +877,7 @@ static s64 __iomap_zero_iter(struct iomap_iter *iter, loff_t pos, u64 length) unsigned offset = offset_in_page(pos); unsigned bytes = min_t(u64, PAGE_SIZE - offset, length); - status = iomap_write_begin(iter, pos, bytes, 0, &page); + status = iomap_write_begin(iter, pos, bytes, &page); if (status) return status; diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 6784a8b..f53c40e 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -140,6 +140,7 @@ struct iomap_page_ops { #define IOMAP_DIRECT (1 << 4) /* direct I/O */ #define IOMAP_NOWAIT (1 << 5) /* do not block */ #define IOMAP_OVERWRITE_ONLY (1 << 6) /* only pure overwrites allowed */ +#define IOMAP_UNSHARE (1 << 7) /* unshare_file_range */ struct iomap_ops { /* -- 2.7.4