From 20970ba65d5a22f2e4efbfa100377722fde56935 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Thu, 6 Jun 2013 14:00:46 -0400 Subject: [PATCH] ext4: use ext4_da_writepages() for all modes Rename ext4_da_writepages() to ext4_writepages() and use it for all modes. We still need to iterate over all the pages in the case of data=journalling, but in the case of nodelalloc/data=ordered (which is what file systems mounted using ext3 backwards compatibility will use) this will allow us to use a much more efficient I/O submission path. Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 41 +++++++++++++++++++++++++++++++---------- include/trace/events/ext4.h | 4 ++-- 2 files changed, 33 insertions(+), 12 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 442c5d2..0db830d 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1799,7 +1799,7 @@ out: * lock so we have to do some magic. * * This function can get called via... - * - ext4_da_writepages after taking page lock (have journal handle) + * - ext4_writepages after taking page lock (have journal handle) * - journal_submit_inode_data_buffers (no journal handle) * - shrink_page_list via the kswapd/direct reclaim (no journal handle) * - grab_page_cache when doing write_begin (have journal handle) @@ -2217,7 +2217,7 @@ static int mpage_map_and_submit_extent(handle_t *handle, /* * Calculate the total number of credits to reserve for one writepages - * iteration. This is called from ext4_da_writepages(). We map an extent of + * iteration. This is called from ext4_writepages(). We map an extent of * upto MAX_WRITEPAGES_EXTENT_LEN blocks and then we go on and finish mapping * the last partial page. So in total we can map MAX_WRITEPAGES_EXTENT_LEN + * bpp - 1 blocks in bpp different extents. @@ -2349,8 +2349,17 @@ out: return err; } -static int ext4_da_writepages(struct address_space *mapping, - struct writeback_control *wbc) +static int __writepage(struct page *page, struct writeback_control *wbc, + void *data) +{ + struct address_space *mapping = data; + int ret = ext4_writepage(page, wbc); + mapping_set_error(mapping, ret); + return ret; +} + +static int ext4_writepages(struct address_space *mapping, + struct writeback_control *wbc) { pgoff_t writeback_index = 0; long nr_to_write = wbc->nr_to_write; @@ -2364,7 +2373,7 @@ static int ext4_da_writepages(struct address_space *mapping, bool done; struct blk_plug plug; - trace_ext4_da_writepages(inode, wbc); + trace_ext4_writepages(inode, wbc); /* * No pages to write? This is mainly a kludge to avoid starting @@ -2374,13 +2383,23 @@ static int ext4_da_writepages(struct address_space *mapping, if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) return 0; + if (ext4_should_journal_data(inode)) { + struct blk_plug plug; + int ret; + + blk_start_plug(&plug); + ret = write_cache_pages(mapping, wbc, __writepage, mapping); + blk_finish_plug(&plug); + return ret; + } + /* * If the filesystem has aborted, it is read-only, so return * right away instead of dumping stack traces later on that * will obscure the real source of the problem. We test * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because * the latter could be true if the filesystem is mounted - * read-only, and in that case, ext4_da_writepages should + * read-only, and in that case, ext4_writepages should * *never* be called, so if that ever happens, we would want * the stack trace. */ @@ -2520,8 +2539,8 @@ retry: mapping->writeback_index = mpd.first_page; out_writepages: - trace_ext4_da_writepages_result(inode, wbc, ret, - nr_to_write - wbc->nr_to_write); + trace_ext4_writepages_result(inode, wbc, ret, + nr_to_write - wbc->nr_to_write); return ret; } @@ -2769,7 +2788,7 @@ int ext4_alloc_da_blocks(struct inode *inode) * laptop_mode, not even desirable). However, to do otherwise * would require replicating code paths in: * - * ext4_da_writepages() -> + * ext4_writepages() -> * write_cache_pages() ---> (via passed in callback function) * __mpage_da_writepage() --> * mpage_add_bh_to_extent() @@ -3213,6 +3232,7 @@ static const struct address_space_operations ext4_aops = { .readpage = ext4_readpage, .readpages = ext4_readpages, .writepage = ext4_writepage, + .writepages = ext4_writepages, .write_begin = ext4_write_begin, .write_end = ext4_write_end, .bmap = ext4_bmap, @@ -3228,6 +3248,7 @@ static const struct address_space_operations ext4_journalled_aops = { .readpage = ext4_readpage, .readpages = ext4_readpages, .writepage = ext4_writepage, + .writepages = ext4_writepages, .write_begin = ext4_write_begin, .write_end = ext4_journalled_write_end, .set_page_dirty = ext4_journalled_set_page_dirty, @@ -3243,7 +3264,7 @@ static const struct address_space_operations ext4_da_aops = { .readpage = ext4_readpage, .readpages = ext4_readpages, .writepage = ext4_writepage, - .writepages = ext4_da_writepages, + .writepages = ext4_writepages, .write_begin = ext4_da_write_begin, .write_end = ext4_da_write_end, .bmap = ext4_bmap, diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h index 832a412..72f523e 100644 --- a/include/trace/events/ext4.h +++ b/include/trace/events/ext4.h @@ -281,7 +281,7 @@ DEFINE_EVENT(ext4__write_end, ext4_da_write_end, TP_ARGS(inode, pos, len, copied) ); -TRACE_EVENT(ext4_da_writepages, +TRACE_EVENT(ext4_writepages, TP_PROTO(struct inode *inode, struct writeback_control *wbc), TP_ARGS(inode, wbc), @@ -379,7 +379,7 @@ TRACE_EVENT(ext4_da_write_pages_extent, __entry->flags) ); -TRACE_EVENT(ext4_da_writepages_result, +TRACE_EVENT(ext4_writepages_result, TP_PROTO(struct inode *inode, struct writeback_control *wbc, int ret, int pages_written), -- 2.7.4