From patchwork Tue Sep 1 19:01:36 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Omar Sandoval X-Patchwork-Id: 7106471 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id B40B99F36E for ; Tue, 1 Sep 2015 19:02:14 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0720120531 for ; Tue, 1 Sep 2015 19:02:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E5A3E20519 for ; Tue, 1 Sep 2015 19:02:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753444AbbIATCA (ORCPT ); Tue, 1 Sep 2015 15:02:00 -0400 Received: from mail-pa0-f50.google.com ([209.85.220.50]:35346 "EHLO mail-pa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752177AbbIATB6 (ORCPT ); Tue, 1 Sep 2015 15:01:58 -0400 Received: by pacfv12 with SMTP id fv12so4559898pac.2 for ; Tue, 01 Sep 2015 12:01:58 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:in-reply-to:references; bh=grNP3C/QXCWzW1xOLlsNlr8ILuFs4idf4YCtUr5/qNY=; b=f82mMsfPwf1BHFHIa2JAFpscsBLVINdMt3rr/CNVmki+HmOmRby3FUYCHQoQ2C6wJZ W1tRiHo6rRZVKKr/M0HW5uQI9un+tbnXso8oBDjgXzDGJwfkuNUzGO2VUvHms+gjix1r WHr1VoG3Nv387vTkHt/SdAfnfU13yc5jN4pnvI3wrCxjyXKQoSqGS6tPe4mPFBjJShYk sWdGFHuLXDzh3PNMSczLjC+77RsWMkXqSuE3dv2gJHzNpsC/l6U4CjIxcbcqzJzsKnzH a91nIjnPUS7GWyvIJLxX1hhwctuuRm2q57FqF3D8IRVncCEbLF6N2ypVjWCowk0tFY+/ R6TQ== X-Gm-Message-State: ALoCoQnxFcwgx3wyZ5f0V14Eiqs4egiQ5E2RgQPonZsxwyESVeNToDeJuTaJpwPMzU1MavRt14hX X-Received: by 10.68.93.133 with SMTP id cu5mr49467727pbb.71.1441134117602; Tue, 01 Sep 2015 12:01:57 -0700 (PDT) Received: from huxley.thefacebook.com ([2620:10d:c090:200::4:58ae]) by smtp.gmail.com with ESMTPSA id cy10sm19029394pdb.13.2015.09.01.12.01.56 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 01 Sep 2015 12:01:57 -0700 (PDT) From: Omar Sandoval To: linux-btrfs@vger.kernel.org Cc: Omar Sandoval Subject: [PATCH 1/6] Btrfs: add extent buffer bitmap operations Date: Tue, 1 Sep 2015 12:01:36 -0700 Message-Id: <36f81ee96c9868b1517dbbda553c14b917b5d5ee.1441131625.git.osandov@fb.com> X-Mailer: git-send-email 2.5.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Omar Sandoval These are going to be used for the free space tree bitmap items. Signed-off-by: Omar Sandoval --- fs/btrfs/extent_io.c | 101 +++++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/extent_io.h | 6 +++ 2 files changed, 107 insertions(+) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 02d05817cbdf..649e3b4eeb1b 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -5475,6 +5475,107 @@ void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, } } +/* + * The extent buffer bitmap operations are done with byte granularity because + * bitmap items are not guaranteed to be aligned to a word and therefore a + * single word in a bitmap may straddle two pages in the extent buffer. + */ +#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE) +#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1) +#define BITMAP_FIRST_BYTE_MASK(start) \ + ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK) +#define BITMAP_LAST_BYTE_MASK(nbits) \ + (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1))) + +int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start, + unsigned long nr) +{ + size_t offset; + char *kaddr; + struct page *page; + size_t byte_offset = BIT_BYTE(nr); + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + start + byte_offset) >> PAGE_CACHE_SHIFT; + + offset = (start_offset + start + byte_offset) & (PAGE_CACHE_SIZE - 1); + page = eb->pages[i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + return 1U & (kaddr[offset] >> (nr & (BITS_PER_BYTE - 1))); +} + +void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start, + unsigned long pos, unsigned long len) +{ + size_t offset; + char *kaddr; + struct page *page; + size_t byte_offset = BIT_BYTE(pos); + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + start + byte_offset) >> PAGE_CACHE_SHIFT; + const unsigned int size = pos + len; + int bits_to_set = BITS_PER_BYTE - (pos % BITS_PER_BYTE); + unsigned int mask_to_set = BITMAP_FIRST_BYTE_MASK(pos); + + offset = (start_offset + start + byte_offset) & (PAGE_CACHE_SIZE - 1); + page = eb->pages[i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + + while (len >= bits_to_set) { + kaddr[offset] |= mask_to_set; + len -= bits_to_set; + bits_to_set = BITS_PER_BYTE; + mask_to_set = ~0U; + if (++offset >= PAGE_CACHE_SIZE && len > 0) { + offset = 0; + page = eb->pages[++i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + } + } + if (len) { + mask_to_set &= BITMAP_LAST_BYTE_MASK(size); + kaddr[offset] |= mask_to_set; + } +} + +void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start, + unsigned long pos, unsigned long len) +{ + size_t offset; + char *kaddr; + struct page *page; + size_t byte_offset = BIT_BYTE(pos); + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + unsigned long i = (start_offset + start + byte_offset) >> PAGE_CACHE_SHIFT; + const unsigned int size = pos + len; + int bits_to_clear = BITS_PER_BYTE - (pos % BITS_PER_BYTE); + unsigned int mask_to_clear = BITMAP_FIRST_BYTE_MASK(pos); + + offset = (start_offset + start + byte_offset) & (PAGE_CACHE_SIZE - 1); + page = eb->pages[i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + + while (len >= bits_to_clear) { + kaddr[offset] &= ~mask_to_clear; + len -= bits_to_clear; + bits_to_clear = BITS_PER_BYTE; + mask_to_clear = ~0U; + if (++offset >= PAGE_CACHE_SIZE && len > 0) { + offset = 0; + page = eb->pages[++i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + } + } + if (len) { + mask_to_clear &= BITMAP_LAST_BYTE_MASK(size); + kaddr[offset] &= ~mask_to_clear; + } +} + static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len) { unsigned long distance = (src > dst) ? src - dst : dst - src; diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index c668f36898d3..9185a20081d7 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -309,6 +309,12 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, unsigned long src_offset, unsigned long len); void memset_extent_buffer(struct extent_buffer *eb, char c, unsigned long start, unsigned long len); +int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start, + unsigned long pos); +void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start, + unsigned long pos, unsigned long len); +void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start, + unsigned long pos, unsigned long len); void clear_extent_buffer_dirty(struct extent_buffer *eb); int set_extent_buffer_dirty(struct extent_buffer *eb); int set_extent_buffer_uptodate(struct extent_buffer *eb);