From 1d410a6e337a0d2d5543ad1d9bccb670a7a05312 Mon Sep 17 00:00:00 2001 From: Mark Fasheh Date: Fri, 7 Sep 2007 14:20:45 -0700 Subject: ocfs2: Small refactor of truncate zeroing code We'll want to reuse most of this when pushing inline data back out to an extent. Keeping this part as a seperate patch helps to keep the upcoming changes for write support uncluttered. The core portion of ocfs2_zero_cluster_pages() responsible for making sure a page is mapped and properly dirtied is abstracted out into it's own function, ocfs2_map_and_dirty_page(). Actual functionality doesn't change, though zeroing becomes optional. We also turn part of ocfs2_free_write_ctxt() into a common function for unlocking and freeing a page array. This operation is very common (and uniform) for Ocfs2 cluster sizes greater than page size, so it makes sense to keep the code in one place. Signed-off-by: Mark Fasheh Reviewed-by: Joel Becker --- fs/ocfs2/alloc.c | 151 ++++++++++++++++++++++++++----------------------------- 1 file changed, 72 insertions(+), 79 deletions(-) (limited to 'fs/ocfs2/alloc.c') diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c index c91706f949f..c81bfdfb992 100644 --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -5633,12 +5633,50 @@ static int ocfs2_ordered_zero_func(handle_t *handle, struct buffer_head *bh) return ocfs2_journal_dirty_data(handle, bh); } +static void ocfs2_map_and_dirty_page(struct inode *inode, handle_t *handle, + unsigned int from, unsigned int to, + struct page *page, int zero, u64 *phys) +{ + int ret, partial = 0; + + ret = ocfs2_map_page_blocks(page, phys, inode, from, to, 0); + if (ret) + mlog_errno(ret); + + if (zero) + zero_user_page(page, from, to - from, KM_USER0); + + /* + * Need to set the buffers we zero'd into uptodate + * here if they aren't - ocfs2_map_page_blocks() + * might've skipped some + */ + if (ocfs2_should_order_data(inode)) { + ret = walk_page_buffers(handle, + page_buffers(page), + from, to, &partial, + ocfs2_ordered_zero_func); + if (ret < 0) + mlog_errno(ret); + } else { + ret = walk_page_buffers(handle, page_buffers(page), + from, to, &partial, + ocfs2_writeback_zero_func); + if (ret < 0) + mlog_errno(ret); + } + + if (!partial) + SetPageUptodate(page); + + flush_dcache_page(page); +} + static void ocfs2_zero_cluster_pages(struct inode *inode, loff_t start, loff_t end, struct page **pages, int numpages, u64 phys, handle_t *handle) { - int i, ret, partial = 0; - void *kaddr; + int i; struct page *page; unsigned int from, to = PAGE_CACHE_SIZE; struct super_block *sb = inode->i_sb; @@ -5659,87 +5697,31 @@ static void ocfs2_zero_cluster_pages(struct inode *inode, loff_t start, BUG_ON(from > PAGE_CACHE_SIZE); BUG_ON(to > PAGE_CACHE_SIZE); - ret = ocfs2_map_page_blocks(page, &phys, inode, from, to, 0); - if (ret) - mlog_errno(ret); - - kaddr = kmap_atomic(page, KM_USER0); - memset(kaddr + from, 0, to - from); - kunmap_atomic(kaddr, KM_USER0); - - /* - * Need to set the buffers we zero'd into uptodate - * here if they aren't - ocfs2_map_page_blocks() - * might've skipped some - */ - if (ocfs2_should_order_data(inode)) { - ret = walk_page_buffers(handle, - page_buffers(page), - from, to, &partial, - ocfs2_ordered_zero_func); - if (ret < 0) - mlog_errno(ret); - } else { - ret = walk_page_buffers(handle, page_buffers(page), - from, to, &partial, - ocfs2_writeback_zero_func); - if (ret < 0) - mlog_errno(ret); - } - - if (!partial) - SetPageUptodate(page); - - flush_dcache_page(page); + ocfs2_map_and_dirty_page(inode, handle, from, to, page, 1, + &phys); start = (page->index + 1) << PAGE_CACHE_SHIFT; } out: - if (pages) { - for (i = 0; i < numpages; i++) { - page = pages[i]; - unlock_page(page); - mark_page_accessed(page); - page_cache_release(page); - } - } + if (pages) + ocfs2_unlock_and_free_pages(pages, numpages); } static int ocfs2_grab_eof_pages(struct inode *inode, loff_t start, loff_t end, - struct page **pages, int *num, u64 *phys) + struct page **pages, int *num) { - int i, numpages = 0, ret = 0; - unsigned int ext_flags; + int numpages, ret = 0; struct super_block *sb = inode->i_sb; struct address_space *mapping = inode->i_mapping; unsigned long index; loff_t last_page_bytes; - BUG_ON(!ocfs2_sparse_alloc(OCFS2_SB(sb))); BUG_ON(start > end); - if (start == end) - goto out; - BUG_ON(start >> OCFS2_SB(sb)->s_clustersize_bits != (end - 1) >> OCFS2_SB(sb)->s_clustersize_bits); - ret = ocfs2_extent_map_get_blocks(inode, start >> sb->s_blocksize_bits, - phys, NULL, &ext_flags); - if (ret) { - mlog_errno(ret); - goto out; - } - - /* Tail is a hole. */ - if (*phys == 0) - goto out; - - /* Tail is marked as unwritten, we can count on write to zero - * in that case. */ - if (ext_flags & OCFS2_EXT_UNWRITTEN) - goto out; - + numpages = 0; last_page_bytes = PAGE_ALIGN(end); index = start >> PAGE_CACHE_SHIFT; do { @@ -5756,14 +5738,8 @@ static int ocfs2_grab_eof_pages(struct inode *inode, loff_t start, loff_t end, out: if (ret != 0) { - if (pages) { - for (i = 0; i < numpages; i++) { - if (pages[i]) { - unlock_page(pages[i]); - page_cache_release(pages[i]); - } - } - } + if (pages) + ocfs2_unlock_and_free_pages(pages, numpages); numpages = 0; } @@ -5784,18 +5760,20 @@ out: int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle, u64 range_start, u64 range_end) { - int ret, numpages; + int ret = 0, numpages; struct page **pages = NULL; u64 phys; + unsigned int ext_flags; + struct super_block *sb = inode->i_sb; /* * File systems which don't support sparse files zero on every * extend. */ - if (!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) + if (!ocfs2_sparse_alloc(OCFS2_SB(sb))) return 0; - pages = kcalloc(ocfs2_pages_per_cluster(inode->i_sb), + pages = kcalloc(ocfs2_pages_per_cluster(sb), sizeof(struct page *), GFP_NOFS); if (pages == NULL) { ret = -ENOMEM; @@ -5803,15 +5781,30 @@ int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle, goto out; } - ret = ocfs2_grab_eof_pages(inode, range_start, range_end, pages, - &numpages, &phys); + if (range_start == range_end) + goto out; + + ret = ocfs2_extent_map_get_blocks(inode, + range_start >> sb->s_blocksize_bits, + &phys, NULL, &ext_flags); if (ret) { mlog_errno(ret); goto out; } - if (numpages == 0) + /* + * Tail is a hole, or is marked unwritten. In either case, we + * can count on read and write to return/push zero's. + */ + if (phys == 0 || ext_flags & OCFS2_EXT_UNWRITTEN) + goto out; + + ret = ocfs2_grab_eof_pages(inode, range_start, range_end, pages, + &numpages); + if (ret) { + mlog_errno(ret); goto out; + } ocfs2_zero_cluster_pages(inode, range_start, range_end, pages, numpages, phys, handle); -- cgit v1.2.3