From 338f379cf7c21e3bc31186f303ac99dc5d2cc613 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 14 Dec 2020 07:57:07 -0500 Subject: [PATCH] fs: Convert vfs_dedupe_file_range_compare to folios We still only operate on a single page of data at a time due to using kmap(). A more complex implementation would work on each page in a folio, but it's not clear that such a complex implementation would be worthwhile. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Reviewed-by: William Kucharski --- fs/remap_range.c | 114 ++++++++++++++++++++++------------------------- 1 file changed, 54 insertions(+), 60 deletions(-) diff --git a/fs/remap_range.c b/fs/remap_range.c index 6d4a9beaa097..231159682907 100644 --- a/fs/remap_range.c +++ b/fs/remap_range.c @@ -146,41 +146,41 @@ static int generic_remap_check_len(struct inode *inode_in, } /* Read a page's worth of file data into the page cache. */ -static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset) +static struct folio *vfs_dedupe_get_folio(struct inode *inode, loff_t pos) { - struct page *page; + struct folio *folio; - page = read_mapping_page(inode->i_mapping, offset >> PAGE_SHIFT, NULL); - if (IS_ERR(page)) - return page; - if (!PageUptodate(page)) { - put_page(page); + folio = read_mapping_folio(inode->i_mapping, pos >> PAGE_SHIFT, NULL); + if (IS_ERR(folio)) + return folio; + if (!folio_test_uptodate(folio)) { + folio_put(folio); return ERR_PTR(-EIO); } - return page; + return folio; } /* - * Lock two pages, ensuring that we lock in offset order if the pages are from - * the same file. + * Lock two folios, ensuring that we lock in offset order if the folios + * are from the same file. */ -static void vfs_lock_two_pages(struct page *page1, struct page *page2) +static void vfs_lock_two_folios(struct folio *folio1, struct folio *folio2) { /* Always lock in order of increasing index. */ - if (page1->index > page2->index) - swap(page1, page2); + if (folio1->index > folio2->index) + swap(folio1, folio2); - lock_page(page1); - if (page1 != page2) - lock_page(page2); + folio_lock(folio1); + if (folio1 != folio2) + folio_lock(folio2); } -/* Unlock two pages, being careful not to unlock the same page twice. */ -static void vfs_unlock_two_pages(struct page *page1, struct page *page2) +/* Unlock two folios, being careful not to unlock the same folio twice. */ +static void vfs_unlock_two_folios(struct folio *folio1, struct folio *folio2) { - unlock_page(page1); - if (page1 != page2) - unlock_page(page2); + folio_unlock(folio1); + if (folio1 != folio2) + folio_unlock(folio2); } /* @@ -188,77 +188,71 @@ static void vfs_unlock_two_pages(struct page *page1, struct page *page2) * Caller must have locked both inodes to prevent write races. */ static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, - struct inode *dest, loff_t destoff, + struct inode *dest, loff_t dstoff, loff_t len, bool *is_same) { - loff_t src_poff; - loff_t dest_poff; - void *src_addr; - void *dest_addr; - struct page *src_page; - struct page *dest_page; - loff_t cmp_len; - bool same; - int error; + bool same = true; + int error = -EINVAL; - error = -EINVAL; - same = true; while (len) { - src_poff = srcoff & (PAGE_SIZE - 1); - dest_poff = destoff & (PAGE_SIZE - 1); - cmp_len = min(PAGE_SIZE - src_poff, - PAGE_SIZE - dest_poff); + struct folio *src_folio, *dst_folio; + void *src_addr, *dst_addr; + loff_t cmp_len = min(PAGE_SIZE - offset_in_page(srcoff), + PAGE_SIZE - offset_in_page(dstoff)); + cmp_len = min(cmp_len, len); if (cmp_len <= 0) goto out_error; - src_page = vfs_dedupe_get_page(src, srcoff); - if (IS_ERR(src_page)) { - error = PTR_ERR(src_page); + src_folio = vfs_dedupe_get_folio(src, srcoff); + if (IS_ERR(src_folio)) { + error = PTR_ERR(src_folio); goto out_error; } - dest_page = vfs_dedupe_get_page(dest, destoff); - if (IS_ERR(dest_page)) { - error = PTR_ERR(dest_page); - put_page(src_page); + dst_folio = vfs_dedupe_get_folio(dest, dstoff); + if (IS_ERR(dst_folio)) { + error = PTR_ERR(dst_folio); + folio_put(src_folio); goto out_error; } - vfs_lock_two_pages(src_page, dest_page); + vfs_lock_two_folios(src_folio, dst_folio); /* - * Now that we've locked both pages, make sure they're still + * Now that we've locked both folios, make sure they're still * mapped to the file data we're interested in. If not, * someone is invalidating pages on us and we lose. */ - if (!PageUptodate(src_page) || !PageUptodate(dest_page) || - src_page->mapping != src->i_mapping || - dest_page->mapping != dest->i_mapping) { + if (!folio_test_uptodate(src_folio) || !folio_test_uptodate(dst_folio) || + src_folio->mapping != src->i_mapping || + dst_folio->mapping != dest->i_mapping) { same = false; goto unlock; } - src_addr = kmap_atomic(src_page); - dest_addr = kmap_atomic(dest_page); + src_addr = kmap_local_folio(src_folio, + offset_in_folio(src_folio, srcoff)); + dst_addr = kmap_local_folio(dst_folio, + offset_in_folio(dst_folio, dstoff)); - flush_dcache_page(src_page); - flush_dcache_page(dest_page); + flush_dcache_folio(src_folio); + flush_dcache_folio(dst_folio); - if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) + if (memcmp(src_addr, dst_addr, cmp_len)) same = false; - kunmap_atomic(dest_addr); - kunmap_atomic(src_addr); + kunmap_local(dst_addr); + kunmap_local(src_addr); unlock: - vfs_unlock_two_pages(src_page, dest_page); - put_page(dest_page); - put_page(src_page); + vfs_unlock_two_folios(src_folio, dst_folio); + folio_put(dst_folio); + folio_put(src_folio); if (!same) break; srcoff += cmp_len; - destoff += cmp_len; + dstoff += cmp_len; len -= cmp_len; }