[PATCH v6 08/22] erofs: use meta buffers for erofs_read_superblock()

Jeffle Xu
2022-03-25T12:24:20Z

The only change is that, meta buffers read cache page without __GFP_FS
flag, which shall not matter.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
fs/erofs/super.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 915eefe0d7e2..12755217631f 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -281,21 +281,19 @@ static int erofs_init_devices(struct super_block *sb,
static int erofs_read_superblock(struct super_block *sb)
{
struct erofs_sb_info *sbi;
- struct page *page;
+ struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
struct erofs_super_block *dsb;
unsigned int blkszbits;
void *data;
int ret;

- page = read_mapping_page(sb->s_bdev->bd_inode->i_mapping, 0, NULL);
- if (IS_ERR(page)) {
+ data = erofs_read_metabuf(&buf, sb, 0, EROFS_KMAP);
+ if (IS_ERR(data)) {
erofs_err(sb, "cannot read erofs superblock");
- return PTR_ERR(page);
+ return PTR_ERR(data);
}

sbi = EROFS_SB(sb);
-
- data = kmap(page);
dsb = (struct erofs_super_block *)(data + EROFS_SUPER_OFFSET);

ret = -EINVAL;
@@ -365,8 +363,7 @@ static int erofs_read_superblock(struct super_block *sb)
if (erofs_sb_has_ztailpacking(sbi))
erofs_info(sb, "EXPERIMENTAL compressed inline data feature in use. Use at your own risk!");
out:
- kunmap(page);
- put_page(page);
+ erofs_put_metabuf(&buf);
return ret;
}

--
2.27.0