2015-08-07 10:37:14

by Chao Yu

Subject: [PATCH 1/4] f2fs: report error of fill_zero

fill_zero can fail due to a lot of reason, but previously we do not handle
its return value, so its callers such as punch_hole/f2fs_zero_range may
report success, but actually can fail because of error occurs inside
fill_zero.

This patch fixes to report correct return value of fill_zero.

Signed-off-by: Chao Yu <[email protected]>
---
fs/f2fs/file.c | 56 ++++++++++++++++++++++++++++++++++++++------------------
1 file changed, 38 insertions(+), 18 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index be69a01..016ed3b 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -695,14 +695,14 @@ const struct inode_operations f2fs_file_inode_operations = {
.fiemap = f2fs_fiemap,
};

-static void fill_zero(struct inode *inode, pgoff_t index,
+static int fill_zero(struct inode *inode, pgoff_t index,
loff_t start, loff_t len)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct page *page;

if (!len)
- return;
+ return 0;

f2fs_balance_fs(sbi);

@@ -710,12 +710,14 @@ static void fill_zero(struct inode *inode, pgoff_t index,
page = get_new_data_page(inode, NULL, index, false);
f2fs_unlock_op(sbi);

- if (!IS_ERR(page)) {
- f2fs_wait_on_page_writeback(page, DATA);
- zero_user(page, start, len);
- set_page_dirty(page);
- f2fs_put_page(page, 1);
- }
+ if (IS_ERR(page))
+ return PTR_ERR(page);
+
+ f2fs_wait_on_page_writeback(page, DATA);
+ zero_user(page, start, len);
+ set_page_dirty(page);
+ f2fs_put_page(page, 1);
+ return 0;
}

int truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end)
@@ -763,14 +765,22 @@ static int punch_hole(struct inode *inode, loff_t offset, loff_t len)
off_end = (offset + len) & (PAGE_CACHE_SIZE - 1);

if (pg_start == pg_end) {
- fill_zero(inode, pg_start, off_start,
+ ret = fill_zero(inode, pg_start, off_start,
off_end - off_start);
+ if (ret)
+ return ret;
} else {
- if (off_start)
- fill_zero(inode, pg_start++, off_start,
- PAGE_CACHE_SIZE - off_start);
- if (off_end)
- fill_zero(inode, pg_end, 0, off_end);
+ if (off_start) {
+ ret = fill_zero(inode, pg_start++, off_start,
+ PAGE_CACHE_SIZE - off_start);
+ if (ret)
+ return ret;
+ }
+ if (off_end) {
+ ret = fill_zero(inode, pg_end, 0, off_end);
+ if (ret)
+ return ret;
+ }

if (pg_start < pg_end) {
struct address_space *mapping = inode->i_mapping;
@@ -961,14 +971,21 @@ static int f2fs_zero_range(struct inode *inode, loff_t offset, loff_t len,
off_end = (offset + len) & (PAGE_CACHE_SIZE - 1);

if (pg_start == pg_end) {
- fill_zero(inode, pg_start, off_start, off_end - off_start);
+ ret = fill_zero(inode, pg_start, off_start,
+ off_end - off_start);
+ if (ret)
+ return ret;
+
if (offset + len > new_size)
new_size = offset + len;
new_size = max_t(loff_t, new_size, offset + len);
} else {
if (off_start) {
- fill_zero(inode, pg_start++, off_start,
- PAGE_CACHE_SIZE - off_start);
+ ret = fill_zero(inode, pg_start++, off_start,
+ PAGE_CACHE_SIZE - off_start);
+ if (ret)
+ return ret;
+
new_size = max_t(loff_t, new_size,
pg_start << PAGE_CACHE_SHIFT);
}
@@ -1010,7 +1027,10 @@ static int f2fs_zero_range(struct inode *inode, loff_t offset, loff_t len,
}

if (off_end) {
- fill_zero(inode, pg_end, 0, off_end);
+ ret = fill_zero(inode, pg_end, 0, off_end);
+ if (ret)
+ goto out;
+
new_size = max_t(loff_t, new_size, offset + len);
}
}
--
2.4.2