From: Zheng Liu Subject: [RFC][PATCH 7/8 v2] ext4: reimplement ext4_find_delay_alloc_range on extent status tree Date: Wed, 22 Aug 2012 14:05:44 +0800 Message-ID: <1345615545-26133-8-git-send-email-wenqing.lz@taobao.com> References: <1345615545-26133-1-git-send-email-wenqing.lz@taobao.com> Cc: Yongqiang Yang , Allison Henderson , Zheng Liu To: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org Return-path: Received: from mail-pb0-f46.google.com ([209.85.160.46]:40491 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757134Ab2HVF4B (ORCPT ); Wed, 22 Aug 2012 01:56:01 -0400 In-Reply-To: <1345615545-26133-1-git-send-email-wenqing.lz@taobao.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Zheng Liu ext4_find_delay_alloc_range is reimplemented on extent status tree. Signed-off-by: Yongqiang Yang Signed-off-by: Allison Henderson Signed-off-by: Zheng Liu --- fs/ext4/ext4.h | 4 -- fs/ext4/ext4_extents.h | 3 +- fs/ext4/extents.c | 112 +++++------------------------------------------ fs/ext4/inode.c | 53 +---------------------- 4 files changed, 14 insertions(+), 158 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 66c592e..f1d5087 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2431,14 +2431,10 @@ enum ext4_state_bits { * never, ever appear in a buffer_head's state * flag. See EXT4_MAP_FROM_CLUSTER to see where * this is used. */ - BH_Da_Mapped, /* Delayed allocated block that now has a mapping. This - * flag is set when ext4_map_blocks is called on a - * delayed allocated block to get its real mapping. */ }; BUFFER_FNS(Uninit, uninit) TAS_BUFFER_FNS(Uninit, uninit) -BUFFER_FNS(Da_Mapped, da_mapped) /* * Add new method to test wether block and inode bitmaps are properly diff --git a/fs/ext4/ext4_extents.h b/fs/ext4/ext4_extents.h index cb1b2c9..603bb11 100644 --- a/fs/ext4/ext4_extents.h +++ b/fs/ext4/ext4_extents.h @@ -314,7 +314,6 @@ extern struct ext4_ext_path *ext4_ext_find_extent(struct inode *, ext4_lblk_t, struct ext4_ext_path *); extern void ext4_ext_drop_refs(struct ext4_ext_path *); extern int ext4_ext_check_inode(struct inode *inode); -extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk, - int search_hint_reverse); +extern int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk); #endif /* _EXT4_EXTENTS */ diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 44cda82..f12d7e8 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3405,115 +3405,27 @@ out: /** * ext4_find_delalloc_range: find delayed allocated block in the given range. * - * Goes through the buffer heads in the range [lblk_start, lblk_end] and returns - * whether there are any buffers marked for delayed allocation. It returns '1' - * on the first delalloc'ed buffer head found. If no buffer head in the given - * range is marked for delalloc, it returns 0. - * lblk_start should always be <= lblk_end. - * search_hint_reverse is to indicate that searching in reverse from lblk_end to - * lblk_start might be more efficient (i.e., we will likely hit the delalloc'ed - * block sooner). This is useful when blocks are truncated sequentially from - * lblk_start towards lblk_end. + * Return 1 if there is a delalloc block in the range, otherwise 0. */ static int ext4_find_delalloc_range(struct inode *inode, ext4_lblk_t lblk_start, - ext4_lblk_t lblk_end, - int search_hint_reverse) + ext4_lblk_t lblk_end) { - struct address_space *mapping = inode->i_mapping; - struct buffer_head *head, *bh = NULL; - struct page *page; - ext4_lblk_t i, pg_lblk; - pgoff_t index; - - if (!test_opt(inode->i_sb, DELALLOC)) - return 0; - - /* reverse search wont work if fs block size is less than page size */ - if (inode->i_blkbits < PAGE_CACHE_SHIFT) - search_hint_reverse = 0; - - if (search_hint_reverse) - i = lblk_end; - else - i = lblk_start; - - index = i >> (PAGE_CACHE_SHIFT - inode->i_blkbits); - - while ((i >= lblk_start) && (i <= lblk_end)) { - page = find_get_page(mapping, index); - if (!page) - goto nextpage; - - if (!page_has_buffers(page)) - goto nextpage; - - head = page_buffers(page); - if (!head) - goto nextpage; - - bh = head; - pg_lblk = index << (PAGE_CACHE_SHIFT - - inode->i_blkbits); - do { - if (unlikely(pg_lblk < lblk_start)) { - /* - * This is possible when fs block size is less - * than page size and our cluster starts/ends in - * middle of the page. So we need to skip the - * initial few blocks till we reach the 'lblk' - */ - pg_lblk++; - continue; - } - - /* Check if the buffer is delayed allocated and that it - * is not yet mapped. (when da-buffers are mapped during - * their writeout, their da_mapped bit is set.) - */ - if (buffer_delay(bh) && !buffer_da_mapped(bh)) { - page_cache_release(page); - trace_ext4_find_delalloc_range(inode, - lblk_start, lblk_end, - search_hint_reverse, - 1, i); - return 1; - } - if (search_hint_reverse) - i--; - else - i++; - } while ((i >= lblk_start) && (i <= lblk_end) && - ((bh = bh->b_this_page) != head)); -nextpage: - if (page) - page_cache_release(page); - /* - * Move to next page. 'i' will be the first lblk in the next - * page. - */ - if (search_hint_reverse) - index--; - else - index++; - i = index << (PAGE_CACHE_SHIFT - inode->i_blkbits); - } + struct extent_status es; - trace_ext4_find_delalloc_range(inode, lblk_start, lblk_end, - search_hint_reverse, 0, 0); - return 0; + es.start = lblk_start; + ext4_es_find_extent(inode, &es); + return (es.start + es.len) >= lblk_end && es.start <= lblk_start; } -int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk, - int search_hint_reverse) +int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); ext4_lblk_t lblk_start, lblk_end; lblk_start = lblk & (~(sbi->s_cluster_ratio - 1)); lblk_end = lblk_start + sbi->s_cluster_ratio - 1; - return ext4_find_delalloc_range(inode, lblk_start, lblk_end, - search_hint_reverse); + return ext4_find_delalloc_range(inode, lblk_start, lblk_end); } /** @@ -3574,7 +3486,7 @@ get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start, lblk_from = lblk_start & (~(sbi->s_cluster_ratio - 1)); lblk_to = lblk_from + c_offset - 1; - if (ext4_find_delalloc_range(inode, lblk_from, lblk_to, 0)) + if (ext4_find_delalloc_range(inode, lblk_from, lblk_to)) allocated_clusters--; } @@ -3584,7 +3496,7 @@ get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start, lblk_from = lblk_start + num_blks; lblk_to = lblk_from + (sbi->s_cluster_ratio - c_offset) - 1; - if (ext4_find_delalloc_range(inode, lblk_from, lblk_to, 0)) + if (ext4_find_delalloc_range(inode, lblk_from, lblk_to)) allocated_clusters--; } @@ -3868,7 +3780,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, if (ext4_ext_in_cache(inode, map->m_lblk, &newex)) { if (!newex.ee_start_lo && !newex.ee_start_hi) { if ((sbi->s_cluster_ratio > 1) && - ext4_find_delalloc_cluster(inode, map->m_lblk, 0)) + ext4_find_delalloc_cluster(inode, map->m_lblk)) map->m_flags |= EXT4_MAP_FROM_CLUSTER; if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) { @@ -3956,7 +3868,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, } if ((sbi->s_cluster_ratio > 1) && - ext4_find_delalloc_cluster(inode, map->m_lblk, 0)) + ext4_find_delalloc_cluster(inode, map->m_lblk)) map->m_flags |= EXT4_MAP_FROM_CLUSTER; /* diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index aa04aa6..e1416c1 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -484,49 +484,6 @@ static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx, } /* - * Sets the BH_Da_Mapped bit on the buffer heads corresponding to the given map. - */ -static void set_buffers_da_mapped(struct inode *inode, - struct ext4_map_blocks *map) -{ - struct address_space *mapping = inode->i_mapping; - struct pagevec pvec; - int i, nr_pages; - pgoff_t index, end; - - index = map->m_lblk >> (PAGE_CACHE_SHIFT - inode->i_blkbits); - end = (map->m_lblk + map->m_len - 1) >> - (PAGE_CACHE_SHIFT - inode->i_blkbits); - - pagevec_init(&pvec, 0); - while (index <= end) { - nr_pages = pagevec_lookup(&pvec, mapping, index, - min(end - index + 1, - (pgoff_t)PAGEVEC_SIZE)); - if (nr_pages == 0) - break; - for (i = 0; i < nr_pages; i++) { - struct page *page = pvec.pages[i]; - struct buffer_head *bh, *head; - - if (unlikely(page->mapping != mapping) || - !PageDirty(page)) - break; - - if (page_has_buffers(page)) { - bh = head = page_buffers(page); - do { - set_buffer_da_mapped(bh); - bh = bh->b_this_page; - } while (bh != head); - } - index++; - } - pagevec_release(&pvec); - } -} - -/* * The ext4_map_blocks() function tries to look up the requested blocks, * and returns if the blocks are already mapped. * @@ -661,13 +618,8 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode, if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) { ext4_clear_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED); - /* If we have successfully mapped the delayed allocated blocks, - * set the BH_Da_Mapped bit on them. Its important to do this - * under the protection of i_data_sem. - */ if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) { int ret; - set_buffers_da_mapped(inode, map); delayed_mapped: /* delayed allocation blocks has been allocated */ ret = ext4_es_remove_extent(inode, map->m_lblk, @@ -1325,7 +1277,6 @@ static void ext4_da_page_release_reservation(struct page *page, if ((offset <= curr_off) && (buffer_delay(bh))) { to_release++; clear_buffer_delay(bh); - clear_buffer_da_mapped(bh); } curr_off = next_off; } while ((bh = bh->b_this_page) != head); @@ -1338,7 +1289,7 @@ static void ext4_da_page_release_reservation(struct page *page, lblk = (page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits)) + ((num_clusters - 1) << sbi->s_cluster_bits); if (sbi->s_cluster_ratio == 1 || - !ext4_find_delalloc_cluster(inode, lblk, 1)) + !ext4_find_delalloc_cluster(inode, lblk)) ext4_da_release_space(inode, 1); num_clusters--; @@ -1444,8 +1395,6 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd, clear_buffer_delay(bh); bh->b_blocknr = pblock; } - if (buffer_da_mapped(bh)) - clear_buffer_da_mapped(bh); if (buffer_unwritten(bh) || buffer_mapped(bh)) BUG_ON(bh->b_blocknr != pblock); -- 1.7.4.1