From patchwork Tue Mar 9 21:21:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ira Weiny X-Patchwork-Id: 12126565 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38460C433E6 for ; Tue, 9 Mar 2021 21:22:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0A55A65259 for ; Tue, 9 Mar 2021 21:22:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231916AbhCIVWT (ORCPT ); Tue, 9 Mar 2021 16:22:19 -0500 Received: from mga06.intel.com ([134.134.136.31]:60761 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230431AbhCIVVw (ORCPT ); Tue, 9 Mar 2021 16:21:52 -0500 IronPort-SDR: WA+9DFQnj+3mkrLZD5TKsH4rnOXKd9/zClhCqmTwU8X/JF0rW5uF9REmUikK9GTu+N8alRd4od t7tGOcGeD6Ag== X-IronPort-AV: E=McAfee;i="6000,8403,9917"; a="249698120" X-IronPort-AV: E=Sophos;i="5.81,236,1610438400"; d="scan'208";a="249698120" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Mar 2021 13:21:52 -0800 IronPort-SDR: SHYY89fSEjFLd2W4ZpIWZrgYiJeHLL+02FYIHAMQNwxqxtDqQ0kgd4G5HYojbjt9lMGQmxnTsC jTcYJoyaflGw== X-IronPort-AV: E=Sophos;i="5.81,236,1610438400"; d="scan'208";a="509424716" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Mar 2021 13:21:51 -0800 From: ira.weiny@intel.com To: Andrew Morton Cc: Ira Weiny , David Sterba , Chris Mason , Josef Bacik , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/3] btrfs: Use memzero_page() instead of open coded kmap pattern Date: Tue, 9 Mar 2021 13:21:37 -0800 Message-Id: <20210309212137.2610186-4-ira.weiny@intel.com> X-Mailer: git-send-email 2.28.0.rc0.12.gb6a658bd00c9 In-Reply-To: <20210309212137.2610186-1-ira.weiny@intel.com> References: <20210309212137.2610186-1-ira.weiny@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Ira Weiny There are many places where kmap/memset/kunmap patterns occur. Use the newly lifted memzero_page() to eliminate direct uses of kmap and leverage the new core functions use of kmap_local_page(). The development of this patch was aided by the following coccinelle script: // // SPDX-License-Identifier: GPL-2.0-only // Find kmap/memset/kunmap pattern and replace with memset*page calls // // NOTE: Offsets and other expressions may be more complex than what the script // will automatically generate. Therefore a catchall rule is provided to find // the pattern which then must be evaluated by hand. // // Confidence: Low // Copyright: (C) 2021 Intel Corporation // URL: http://coccinelle.lip6.fr/ // Comments: // Options: // // Then the memset pattern // @ memset_rule1 @ expression page, V, L, Off; identifier ptr; type VP; @@ ( -VP ptr = kmap(page); | -ptr = kmap(page); | -VP ptr = kmap_atomic(page); | -ptr = kmap_atomic(page); ) <+... ( -memset(ptr, 0, L); +memzero_page(page, 0, L); | -memset(ptr + Off, 0, L); +memzero_page(page, Off, L); | -memset(ptr, V, L); +memset_page(page, V, 0, L); | -memset(ptr + Off, V, L); +memset_page(page, V, Off, L); ) ...+> ( -kunmap(page); | -kunmap_atomic(ptr); ) // Remove any pointers left unused @ depends on memset_rule1 @ identifier memset_rule1.ptr; type VP, VP1; @@ -VP ptr; ... when != ptr; ? VP1 ptr; // // Catch all // @ memset_rule2 @ expression page; identifier ptr; expression GenTo, GenSize, GenValue; type VP; @@ ( -VP ptr = kmap(page); | -ptr = kmap(page); | -VP ptr = kmap_atomic(page); | -ptr = kmap_atomic(page); ) <+... ( // // Some call sites have complex expressions within the memset/memcpy // The follow are catch alls which need to be evaluated by hand. // -memset(GenTo, 0, GenSize); +memzero_pageExtra(page, GenTo, GenSize); | -memset(GenTo, GenValue, GenSize); +memset_pageExtra(page, GenValue, GenTo, GenSize); ) ...+> ( -kunmap(page); | -kunmap_atomic(ptr); ) // Remove any pointers left unused @ depends on memset_rule2 @ identifier memset_rule2.ptr; type VP, VP1; @@ -VP ptr; ... when != ptr; ? VP1 ptr; // Signed-off-by: Ira Weiny Reviewed-by: David Sterba --- Changes from v2: Refactor to use memzero_page() per Linus Changes from v1: Update commit message per David https://lore.kernel.org/lkml/20210209151442.GU1993@suse.cz/ --- fs/btrfs/compression.c | 5 +---- fs/btrfs/extent_io.c | 22 ++++------------------ fs/btrfs/inode.c | 33 ++++++++++----------------------- fs/btrfs/reflink.c | 6 +----- fs/btrfs/zlib.c | 5 +---- fs/btrfs/zstd.c | 5 +---- 6 files changed, 18 insertions(+), 58 deletions(-) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 2600703fab83..b4ed708b0edb 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -586,16 +586,13 @@ static noinline int add_ra_bio_pages(struct inode *inode, free_extent_map(em); if (page->index == end_index) { - char *userpage; size_t zero_offset = offset_in_page(isize); if (zero_offset) { int zeros; zeros = PAGE_SIZE - zero_offset; - userpage = kmap_atomic(page); - memset(userpage + zero_offset, 0, zeros); + memzero_page(page, zero_offset, zeros); flush_dcache_page(page); - kunmap_atomic(userpage); } } diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 4dfb3ead1175..4aea921e33b3 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -3381,15 +3381,12 @@ int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, } if (page->index == last_byte >> PAGE_SHIFT) { - char *userpage; size_t zero_offset = offset_in_page(last_byte); if (zero_offset) { iosize = PAGE_SIZE - zero_offset; - userpage = kmap_atomic(page); - memset(userpage + zero_offset, 0, iosize); + memzero_page(page, zero_offset, iosize); flush_dcache_page(page); - kunmap_atomic(userpage); } } begin_page_read(fs_info, page); @@ -3398,14 +3395,11 @@ int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, u64 disk_bytenr; if (cur >= last_byte) { - char *userpage; struct extent_state *cached = NULL; iosize = PAGE_SIZE - pg_offset; - userpage = kmap_atomic(page); - memset(userpage + pg_offset, 0, iosize); + memzero_page(page, pg_offset, iosize); flush_dcache_page(page); - kunmap_atomic(userpage); set_extent_uptodate(tree, cur, cur + iosize - 1, &cached, GFP_NOFS); unlock_extent_cached(tree, cur, @@ -3488,13 +3482,10 @@ int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, /* we've found a hole, just zero and go on */ if (block_start == EXTENT_MAP_HOLE) { - char *userpage; struct extent_state *cached = NULL; - userpage = kmap_atomic(page); - memset(userpage + pg_offset, 0, iosize); + memzero_page(page, pg_offset, iosize); flush_dcache_page(page); - kunmap_atomic(userpage); set_extent_uptodate(tree, cur, cur + iosize - 1, &cached, GFP_NOFS); @@ -3805,12 +3796,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, } if (page->index == end_index) { - char *userpage; - - userpage = kmap_atomic(page); - memset(userpage + pg_offset, 0, - PAGE_SIZE - pg_offset); - kunmap_atomic(userpage); + memzero_page(page, pg_offset, PAGE_SIZE - pg_offset); flush_dcache_page(page); } diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 9ae1aa9166aa..a9db214c6397 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -641,17 +641,12 @@ static noinline int compress_file_range(struct async_chunk *async_chunk) if (!ret) { unsigned long offset = offset_in_page(total_compressed); struct page *page = pages[nr_pages - 1]; - char *kaddr; /* zero the tail end of the last page, we might be * sending it down to disk */ - if (offset) { - kaddr = kmap_atomic(page); - memset(kaddr + offset, 0, - PAGE_SIZE - offset); - kunmap_atomic(kaddr); - } + if (offset) + memzero_page(page, offset, PAGE_SIZE - offset); will_compress = 1; } } @@ -4829,7 +4824,6 @@ int btrfs_truncate_block(struct btrfs_inode *inode, loff_t from, loff_t len, struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; struct extent_changeset *data_reserved = NULL; - char *kaddr; bool only_release_metadata = false; u32 blocksize = fs_info->sectorsize; pgoff_t index = from >> PAGE_SHIFT; @@ -4921,15 +4915,13 @@ int btrfs_truncate_block(struct btrfs_inode *inode, loff_t from, loff_t len, if (offset != blocksize) { if (!len) len = blocksize - offset; - kaddr = kmap(page); if (front) - memset(kaddr + (block_start - page_offset(page)), - 0, offset); + memzero_page(page, (block_start - page_offset(page)), + offset); else - memset(kaddr + (block_start - page_offset(page)) + offset, - 0, len); + memzero_page(page, (block_start - page_offset(page)) + offset, + len); flush_dcache_page(page); - kunmap(page); } ClearPageChecked(page); set_page_dirty(page); @@ -6828,11 +6820,9 @@ static noinline int uncompress_inline(struct btrfs_path *path, * cover that region here. */ - if (max_size + pg_offset < PAGE_SIZE) { - char *map = kmap(page); - memset(map + pg_offset + max_size, 0, PAGE_SIZE - max_size - pg_offset); - kunmap(page); - } + if (max_size + pg_offset < PAGE_SIZE) + memzero_page(page, pg_offset + max_size, + PAGE_SIZE - max_size - pg_offset); kfree(tmp); return ret; } @@ -8498,7 +8488,6 @@ vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; struct extent_changeset *data_reserved = NULL; - char *kaddr; unsigned long zero_start; loff_t size; vm_fault_t ret; @@ -8610,10 +8599,8 @@ vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf) zero_start = PAGE_SIZE; if (zero_start != PAGE_SIZE) { - kaddr = kmap(page); - memset(kaddr + zero_start, 0, PAGE_SIZE - zero_start); + memzero_page(page, zero_start, PAGE_SIZE - zero_start); flush_dcache_page(page); - kunmap(page); } ClearPageChecked(page); set_page_dirty(page); diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c index 762881b777b3..83126f0e952c 100644 --- a/fs/btrfs/reflink.c +++ b/fs/btrfs/reflink.c @@ -129,12 +129,8 @@ static int copy_inline_to_page(struct btrfs_inode *inode, * So what's in the range [500, 4095] corresponds to zeroes. */ if (datal < block_size) { - char *map; - - map = kmap(page); - memset(map + datal, 0, block_size - datal); + memzero_page(page, datal, block_size - datal); flush_dcache_page(page); - kunmap(page); } SetPageUptodate(page); diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c index d524acf7b3e5..c3fa7d3fa770 100644 --- a/fs/btrfs/zlib.c +++ b/fs/btrfs/zlib.c @@ -375,7 +375,6 @@ int zlib_decompress(struct list_head *ws, unsigned char *data_in, unsigned long bytes_left; unsigned long total_out = 0; unsigned long pg_offset = 0; - char *kaddr; destlen = min_t(unsigned long, destlen, PAGE_SIZE); bytes_left = destlen; @@ -455,9 +454,7 @@ int zlib_decompress(struct list_head *ws, unsigned char *data_in, * end of the inline extent (destlen) to the end of the page */ if (pg_offset < destlen) { - kaddr = kmap_atomic(dest_page); - memset(kaddr + pg_offset, 0, destlen - pg_offset); - kunmap_atomic(kaddr); + memzero_page(dest_page, pg_offset, destlen - pg_offset); } return ret; } diff --git a/fs/btrfs/zstd.c b/fs/btrfs/zstd.c index 8e9626d63976..3e26b466476a 100644 --- a/fs/btrfs/zstd.c +++ b/fs/btrfs/zstd.c @@ -631,7 +631,6 @@ int zstd_decompress(struct list_head *ws, unsigned char *data_in, size_t ret2; unsigned long total_out = 0; unsigned long pg_offset = 0; - char *kaddr; stream = ZSTD_initDStream( ZSTD_BTRFS_MAX_INPUT, workspace->mem, workspace->size); @@ -696,9 +695,7 @@ int zstd_decompress(struct list_head *ws, unsigned char *data_in, ret = 0; finish: if (pg_offset < destlen) { - kaddr = kmap_atomic(dest_page); - memset(kaddr + pg_offset, 0, destlen - pg_offset); - kunmap_atomic(kaddr); + memzero_page(dest_page, pg_offset, destlen - pg_offset); } return ret; }