From 090f32ee4ef0a59c738963c6b0a6948cc5dee84c Mon Sep 17 00:00:00 2001 From: Lukas Czerner Date: Sun, 20 Apr 2014 23:44:47 -0400 Subject: ext4: get rid of EXT4_MAP_UNINIT flag Currently EXT4_MAP_UNINIT is used in dioread_nolock case to mark the cases where we're using dioread_nolock and we're writing into either unallocated, or unwritten extent, because we need to make sure that any DIO write into that inode will wait for the extent conversion. However EXT4_MAP_UNINIT is not only entirely misleading name but also unnecessary because we can check for EXT4_MAP_UNWRITTEN in the dioread_nolock case instead. This commit removes EXT4_MAP_UNINIT flag. Signed-off-by: Lukas Czerner Signed-off-by: "Theodore Ts'o" --- include/trace/events/ext4.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include') diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h index 6a1a0245474f..9995d3b588a8 100644 --- a/include/trace/events/ext4.h +++ b/include/trace/events/ext4.h @@ -51,7 +51,6 @@ struct extent_status; { EXT4_MAP_MAPPED, "M" }, \ { EXT4_MAP_UNWRITTEN, "U" }, \ { EXT4_MAP_BOUNDARY, "B" }, \ - { EXT4_MAP_UNINIT, "u" }, \ { EXT4_MAP_FROM_CLUSTER, "C" }) #define show_free_flags(flags) __print_flags(flags, "|", \ -- cgit v1.2.3 From 556615dcbf38b0a92a9e659f52c06686270dfc16 Mon Sep 17 00:00:00 2001 From: Lukas Czerner Date: Sun, 20 Apr 2014 23:45:47 -0400 Subject: ext4: rename uninitialized extents to unwritten Currently in ext4 there is quite a mess when it comes to naming unwritten extents. Sometimes we call it uninitialized and sometimes we refer to it as unwritten. The right name for the extent which has been allocated but does not contain any written data is _unwritten_. Other file systems are using this name consistently, even the buffer head state refers to it as unwritten. We need to fix this confusion in ext4. This commit changes every reference to an uninitialized extent (meaning allocated but unwritten) to unwritten extent. This includes comments, function names and variable names. It even covers abbreviation of the word uninitialized (such as uninit) and some misspellings. This commit does not change any of the code paths at all. This has been confirmed by comparing md5sums of the assembly code of each object file after all the function names were stripped from it. Signed-off-by: Lukas Czerner Signed-off-by: "Theodore Ts'o" --- include/trace/events/ext4.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h index 9995d3b588a8..d4f70a7fe876 100644 --- a/include/trace/events/ext4.h +++ b/include/trace/events/ext4.h @@ -36,7 +36,7 @@ struct extent_status; #define show_map_flags(flags) __print_flags(flags, "|", \ { EXT4_GET_BLOCKS_CREATE, "CREATE" }, \ - { EXT4_GET_BLOCKS_UNINIT_EXT, "UNINIT" }, \ + { EXT4_GET_BLOCKS_UNWRIT_EXT, "UNWRIT" }, \ { EXT4_GET_BLOCKS_DELALLOC_RESERVE, "DELALLOC" }, \ { EXT4_GET_BLOCKS_PRE_IO, "PRE_IO" }, \ { EXT4_GET_BLOCKS_CONVERT, "CONVERT" }, \ @@ -1496,7 +1496,7 @@ DEFINE_EVENT(ext4__truncate, ext4_truncate_exit, TP_ARGS(inode) ); -/* 'ux' is the uninitialized extent. */ +/* 'ux' is the unwritten extent. */ TRACE_EVENT(ext4_ext_convert_to_initialized_enter, TP_PROTO(struct inode *inode, struct ext4_map_blocks *map, struct ext4_extent *ux), @@ -1532,7 +1532,7 @@ TRACE_EVENT(ext4_ext_convert_to_initialized_enter, ); /* - * 'ux' is the uninitialized extent. + * 'ux' is the unwritten extent. * 'ix' is the initialized extent to which blocks are transferred. */ TRACE_EVENT(ext4_ext_convert_to_initialized_fastpath, @@ -1810,7 +1810,7 @@ DEFINE_EVENT(ext4__trim, ext4_trim_all_free, TP_ARGS(sb, group, start, len) ); -TRACE_EVENT(ext4_ext_handle_uninitialized_extents, +TRACE_EVENT(ext4_ext_handle_unwritten_extents, TP_PROTO(struct inode *inode, struct ext4_map_blocks *map, int flags, unsigned int allocated, ext4_fsblk_t newblock), -- cgit v1.2.3 From 1c8349a17137b93f0a83f276c764a6df1b9a116e Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Mon, 12 May 2014 08:12:25 -0400 Subject: ext4: fix data integrity sync in ordered mode When we perform a data integrity sync we tag all the dirty pages with PAGECACHE_TAG_TOWRITE at start of ext4_da_writepages. Later we check for this tag in write_cache_pages_da and creates a struct mpage_da_data containing contiguously indexed pages tagged with this tag and sync these pages with a call to mpage_da_map_and_submit. This process is done in while loop until all the PAGECACHE_TAG_TOWRITE pages are synced. We also do journal start and stop in each iteration. journal_stop could initiate journal commit which would call ext4_writepage which in turn will call ext4_bio_write_page even for delayed OR unwritten buffers. When ext4_bio_write_page is called for such buffers, even though it does not sync them but it clears the PAGECACHE_TAG_TOWRITE of the corresponding page and hence these pages are also not synced by the currently running data integrity sync. We will end up with dirty pages although sync is completed. This could cause a potential data loss when the sync call is followed by a truncate_pagecache call, which is exactly the case in collapse_range. (It will cause generic/127 failure in xfstests) To avoid this issue, we can use set_page_writeback_keepwrite instead of set_page_writeback, which doesn't clear TOWRITE tag. Cc: stable@vger.kernel.org Signed-off-by: Namjae Jeon Signed-off-by: Ashish Sangwan Signed-off-by: "Theodore Ts'o" Reviewed-by: Jan Kara --- include/linux/page-flags.h | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index d1fe1a761047..ca71a1d347a0 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -317,13 +317,23 @@ CLEARPAGEFLAG(Uptodate, uptodate) extern void cancel_dirty_page(struct page *page, unsigned int account_size); int test_clear_page_writeback(struct page *page); -int test_set_page_writeback(struct page *page); +int __test_set_page_writeback(struct page *page, bool keep_write); + +#define test_set_page_writeback(page) \ + __test_set_page_writeback(page, false) +#define test_set_page_writeback_keepwrite(page) \ + __test_set_page_writeback(page, true) static inline void set_page_writeback(struct page *page) { test_set_page_writeback(page); } +static inline void set_page_writeback_keepwrite(struct page *page) +{ + test_set_page_writeback_keepwrite(page); +} + #ifdef CONFIG_PAGEFLAGS_EXTENDED /* * System with lots of page flags available. This allows separate -- cgit v1.2.3