[PATCH 13/13] f2fs: handle EIO not to break fs consistency

[Jaegeuk Kim <jaegeuk@kernel.org>]

There are two rules when EIO is occurred.
1. don't write any checkpoint data to preserve the previous checkpoint
2. don't lose the cached data/node/meta pages

So, at first, this patch adds set_page_dirty in f2fs_write_end_io's failure.
Then, writing checkpoint/dentry/node blocks is not allowed.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/checkpoint.c | 47 +++++++++++++++++++++++++++++++++--------------
 fs/f2fs/data.c       | 10 +++++++++-
 fs/f2fs/f2fs.h       |  1 +
 fs/f2fs/node.c       |  2 ++
 fs/f2fs/super.c      |  3 +++
 5 files changed, 48 insertions(+), 15 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index d074e27..b365c64 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -160,14 +160,11 @@ static int f2fs_write_meta_page(struct page *page,
 		goto redirty_out;
 	if (wbc->for_reclaim)
 		goto redirty_out;
-
-	/* Should not write any meta pages, if any IO error was occurred */
 	if (unlikely(f2fs_cp_error(sbi)))
-		goto no_write;
+		goto redirty_out;
 
 	f2fs_wait_on_page_writeback(page, META);
 	write_meta_page(sbi, page);
-no_write:
 	dec_page_count(sbi, F2FS_DIRTY_META);
 	unlock_page(page);
 	return 0;
@@ -348,7 +345,7 @@ bool exist_written_data(struct f2fs_sb_info *sbi, nid_t ino, int mode)
 	return e ? true : false;
 }
 
-static void release_dirty_inode(struct f2fs_sb_info *sbi)
+void release_dirty_inode(struct f2fs_sb_info *sbi)
 {
 	struct ino_entry *e, *tmp;
 	int i;
@@ -737,7 +734,7 @@ retry:
 /*
  * Freeze all the FS-operations for checkpoint.
  */
-static void block_operations(struct f2fs_sb_info *sbi)
+static int block_operations(struct f2fs_sb_info *sbi)
 {
 	struct writeback_control wbc = {
 		.sync_mode = WB_SYNC_ALL,
@@ -745,6 +742,7 @@ static void block_operations(struct f2fs_sb_info *sbi)
 		.for_reclaim = 0,
 	};
 	struct blk_plug plug;
+	int err = 0;
 
 	blk_start_plug(&plug);
 
@@ -754,6 +752,10 @@ retry_flush_dents:
 	if (get_pages(sbi, F2FS_DIRTY_DENTS)) {
 		f2fs_unlock_all(sbi);
 		sync_dirty_dir_inodes(sbi);
+		if (unlikely(f2fs_cp_error(sbi))) {
+			err = -EIO;
+			goto out;
+		}
 		goto retry_flush_dents;
 	}
 
@@ -767,9 +769,16 @@ retry_flush_nodes:
 	if (get_pages(sbi, F2FS_DIRTY_NODES)) {
 		up_write(&sbi->node_write);
 		sync_node_pages(sbi, 0, &wbc);
+		if (unlikely(f2fs_cp_error(sbi))) {
+			f2fs_unlock_all(sbi);
+			err = -EIO;
+			goto out;
+		}
 		goto retry_flush_nodes;
 	}
+out:
 	blk_finish_plug(&plug);
+	return err;
 }
 
 static void unblock_operations(struct f2fs_sb_info *sbi)
@@ -813,8 +822,11 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
 	discard_next_dnode(sbi, NEXT_FREE_BLKADDR(sbi, curseg));
 
 	/* Flush all the NAT/SIT pages */
-	while (get_pages(sbi, F2FS_DIRTY_META))
+	while (get_pages(sbi, F2FS_DIRTY_META)) {
 		sync_meta_pages(sbi, META, LONG_MAX);
+		if (unlikely(f2fs_cp_error(sbi)))
+			return;
+	}
 
 	next_free_nid(sbi, &last_nid);
 
@@ -931,14 +943,19 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
 	sbi->last_valid_block_count = sbi->total_valid_block_count;
 	sbi->alloc_valid_block_count = 0;
 
+	if (unlikely(f2fs_cp_error(sbi)))
+		return;
+
 	/* Here, we only have one bio having CP pack */
 	sync_meta_pages(sbi, META_FLUSH, LONG_MAX);
 
-	if (!f2fs_cp_error(sbi)) {
-		clear_prefree_segments(sbi);
-		release_dirty_inode(sbi);
-		F2FS_RESET_SB_DIRT(sbi);
-	}
+	release_dirty_inode(sbi);
+
+	if (unlikely(f2fs_cp_error(sbi)))
+		return;
+
+	clear_prefree_segments(sbi);
+	F2FS_RESET_SB_DIRT(sbi);
 }
 
 /*
@@ -955,8 +972,10 @@ void write_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
 
 	if (!sbi->s_dirty)
 		goto out;
-
-	block_operations(sbi);
+	if (unlikely(f2fs_cp_error(sbi)))
+		goto out;
+	if (block_operations(sbi))
+		goto out;
 
 	trace_f2fs_write_checkpoint(sbi->sb, is_umount, "finish block_ops");
 
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index ac3ccc2..68834e2 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -53,7 +53,7 @@ static void f2fs_write_end_io(struct bio *bio, int err)
 		struct page *page = bvec->bv_page;
 
 		if (unlikely(err)) {
-			SetPageError(page);
+			set_page_dirty(page);
 			set_bit(AS_EIO, &page->mapping->flags);
 			f2fs_stop_checkpoint(sbi);
 		}
@@ -836,10 +836,18 @@ write:
 
 	/* Dentry blocks are controlled by checkpoint */
 	if (S_ISDIR(inode->i_mode)) {
+		if (unlikely(f2fs_cp_error(sbi)))
+			goto redirty_out;
 		err = do_write_data_page(page, &fio);
 		goto done;
 	}
 
+	if (unlikely(f2fs_cp_error(sbi))) {
+		SetPageError(page);
+		unlock_page(page);
+		return 0;
+	}
+
 	if (!wbc->for_reclaim)
 		need_balance_fs = true;
 	else if (has_not_enough_free_secs(sbi, 0))
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 46ceb88..2d009ae 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1267,6 +1267,7 @@ int ra_meta_pages(struct f2fs_sb_info *, int, int, int);
 long sync_meta_pages(struct f2fs_sb_info *, enum page_type, long);
 void add_dirty_inode(struct f2fs_sb_info *, nid_t, int type);
 void remove_dirty_inode(struct f2fs_sb_info *, nid_t, int type);
+void release_dirty_inode(struct f2fs_sb_info *);
 bool exist_written_data(struct f2fs_sb_info *, nid_t, int);
 int acquire_orphan_inode(struct f2fs_sb_info *);
 void release_orphan_inode(struct f2fs_sb_info *);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 9f126f8..d2f7842 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1215,6 +1215,8 @@ static int f2fs_write_node_page(struct page *page,
 
 	if (unlikely(sbi->por_doing))
 		goto redirty_out;
+	if (unlikely(f2fs_cp_error(sbi)))
+		goto redirty_out;
 
 	f2fs_wait_on_page_writeback(page, NODE);
 
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index c4f90cd..c999d67 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -435,6 +435,9 @@ static void f2fs_put_super(struct super_block *sb)
 	if (sbi->s_dirty)
 		write_checkpoint(sbi, true);
 
+	/* EIO will skip do checkpoint, so here we need to release this */
+	release_dirty_inode(sbi);
+
 	iput(sbi->node_inode);
 	iput(sbi->meta_inode);
 
-- 
1.8.5.2 (Apple Git-48)


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