On Tue, Jul 05, 2022 at 04:22:02PM +0200, Fabio M. De Francesco wrote:
> zonefs_read_super() acquires a page with alloc_page(GFP_KERNEL). That
> page cannot come from ZONE_HIGHMEM, thus there's no need to map it with
> kmap().
>
> Therefore, use a plain page_address() on that page.
>
> Suggested-by: Ira Weiny <ira.weiny@xxxxxxxxx>
Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@xxxxxxxxx>
> ---
> fs/zonefs/super.c | 16 +++++++---------
> 1 file changed, 7 insertions(+), 9 deletions(-)
>
> diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c
> index 053299758deb..bd4e4be97a68 100644
> --- a/fs/zonefs/super.c
> +++ b/fs/zonefs/super.c
> @@ -1687,11 +1687,11 @@ static int zonefs_read_super(struct super_block *sb)
> if (ret)
> goto free_page;
>
> - super = kmap(page);
> + super = page_address(page);
>
> ret = -EINVAL;
> if (le32_to_cpu(super->s_magic) != ZONEFS_MAGIC)
> - goto unmap;
> + goto free_page;
>
> stored_crc = le32_to_cpu(super->s_crc);
> super->s_crc = 0;
> @@ -1699,14 +1699,14 @@ static int zonefs_read_super(struct super_block *sb)
> if (crc != stored_crc) {
> zonefs_err(sb, "Invalid checksum (Expected 0x%08x, got 0x%08x)",
> crc, stored_crc);
> - goto unmap;
> + goto free_page;
> }
>
> sbi->s_features = le64_to_cpu(super->s_features);
> if (sbi->s_features & ~ZONEFS_F_DEFINED_FEATURES) {
> zonefs_err(sb, "Unknown features set 0x%llx\n",
> sbi->s_features);
> - goto unmap;
> + goto free_page;
> }
>
> if (sbi->s_features & ZONEFS_F_UID) {
> @@ -1714,7 +1714,7 @@ static int zonefs_read_super(struct super_block *sb)
> le32_to_cpu(super->s_uid));
> if (!uid_valid(sbi->s_uid)) {
> zonefs_err(sb, "Invalid UID feature\n");
> - goto unmap;
> + goto free_page;
> }
> }
>
> @@ -1723,7 +1723,7 @@ static int zonefs_read_super(struct super_block *sb)
> le32_to_cpu(super->s_gid));
> if (!gid_valid(sbi->s_gid)) {
> zonefs_err(sb, "Invalid GID feature\n");
> - goto unmap;
> + goto free_page;
> }
> }
>
> @@ -1732,14 +1732,12 @@ static int zonefs_read_super(struct super_block *sb)
>
> if (memchr_inv(super->s_reserved, 0, sizeof(super->s_reserved))) {
> zonefs_err(sb, "Reserved area is being used\n");
> - goto unmap;
> + goto free_page;
> }
>
> import_uuid(&sbi->s_uuid, super->s_uuid);
> ret = 0;
>
> -unmap:
> - kunmap(page);
> free_page:
> __free_page(page);
>
> --
> 2.36.1
>
