[PATCH 1/2] f2fs: clear PageError on the read path

From: Jaegeuk Kim
Date: Tue Sep 25 2018 - 21:46:23 EST


When running fault injection test, I hit somewhat wrong behavior in f2fs_gc ->
gc_data_segment():

0. fault injection generated some PageError'ed pages

1. gc_data_segment
-> f2fs_get_read_data_page(REQ_RAHEAD)

2. move_data_page
-> f2fs_get_lock_data_page()
-> f2f_get_read_data_page()
-> f2fs_submit_page_read()
-> submit_bio(READ)
-> return EIO due to PageError
-> fail to move data

Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
fs/f2fs/data.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 41102c227eee..cb3ebcae0398 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -77,7 +77,8 @@ static void __read_end_io(struct bio *bio)
/* PG_error was set if any post_read step failed */
if (bio->bi_status || PageError(page)) {
ClearPageUptodate(page);
- SetPageError(page);
+ /* will re-read again later */
+ ClearPageError(page);
} else {
SetPageUptodate(page);
}
@@ -591,6 +592,7 @@ static int f2fs_submit_page_read(struct inode *inode, struct page *page,
bio_put(bio);
return -EFAULT;
}
+ ClearPageError(page);
__submit_bio(F2FS_I_SB(inode), bio, DATA);
return 0;
}
@@ -1571,6 +1573,7 @@ static int f2fs_mpage_readpages(struct address_space *mapping,
if (bio_add_page(bio, page, blocksize, 0) < blocksize)
goto submit_and_realloc;

+ ClearPageError(page);
last_block_in_bio = block_nr;
goto next_page;
set_error_page:
--
2.17.0.441.gb46fe60e1d-goog