Re: [PATCH RFC v2 for-6.8/block 16/18] ext4: use new helper to read sb block

Jan Kara
2023-12-11T17:16:43Z

On Mon 11-12-23 22:08:08, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@huawei.com>
>
> Remove __ext4_sb_bread_gfp() and ext4_buffer_uptodate() that is defined
> by ext4, and convert to use common helper __bread_gfp2() and
> buffer_uptodate_or_error().
>
> Signed-off-by: Yu Kuai <yukuai3@huawei.com>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

Honza

> ---
> fs/ext4/ext4.h | 13 -------------
> fs/ext4/inode.c | 8 ++++----
> fs/ext4/super.c | 45 ++++++++++-----------------------------------
> fs/ext4/symlink.c | 2 +-
> 4 files changed, 15 insertions(+), 53 deletions(-)
>
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index a5d784872303..8377f6c5264f 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -3824,19 +3824,6 @@ extern const struct iomap_ops ext4_iomap_ops;
> extern const struct iomap_ops ext4_iomap_overwrite_ops;
> extern const struct iomap_ops ext4_iomap_report_ops;
>
> -static inline int ext4_buffer_uptodate(struct buffer_head *bh)
> -{
> - /*
> - * If the buffer has the write error flag, we have failed
> - * to write out data in the block. In this case, we don't
> - * have to read the block because we may read the old data
> - * successfully.
> - */
> - if (buffer_write_io_error(bh))
> - set_buffer_uptodate(bh);
> - return buffer_uptodate(bh);
> -}
> -
> #endif /* __KERNEL__ */
>
> #define EFSBADCRC EBADMSG /* Bad CRC detected */
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 61277f7f8722..efb0af6f02f7 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -887,7 +887,7 @@ struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
> bh = ext4_getblk(handle, inode, block, map_flags);
> if (IS_ERR(bh))
> return bh;
> - if (!bh || ext4_buffer_uptodate(bh))
> + if (!bh || buffer_uptodate_or_error(bh))
> return bh;
>
> ret = ext4_read_bh_lock(bh, REQ_META | REQ_PRIO, true);
> @@ -915,7 +915,7 @@ int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
>
> for (i = 0; i < bh_count; i++)
> /* Note that NULL bhs[i] is valid because of holes. */
> - if (bhs[i] && !ext4_buffer_uptodate(bhs[i]))
> + if (bhs[i] && !buffer_uptodate_or_error(bhs[i]))
> ext4_read_bh_lock(bhs[i], REQ_META | REQ_PRIO, false);
>
> if (!wait)
> @@ -4392,11 +4392,11 @@ static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino,
> bh = sb_getblk(sb, block);
> if (unlikely(!bh))
> return -ENOMEM;
> - if (ext4_buffer_uptodate(bh))
> + if (buffer_uptodate_or_error(bh))
> goto has_buffer;
>
> lock_buffer(bh);
> - if (ext4_buffer_uptodate(bh)) {
> + if (buffer_uptodate_or_error(bh)) {
> /* Someone brought it uptodate while we waited */
> unlock_buffer(bh);
> goto has_buffer;
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index c5fcf377ab1f..ae41204f52d4 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -180,7 +180,7 @@ void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
> {
> BUG_ON(!buffer_locked(bh));
>
> - if (ext4_buffer_uptodate(bh)) {
> + if (buffer_uptodate_or_error(bh)) {
> unlock_buffer(bh);
> return;
> }
> @@ -191,7 +191,7 @@ int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags, bh_end_io_t *end_io
> {
> BUG_ON(!buffer_locked(bh));
>
> - if (ext4_buffer_uptodate(bh)) {
> + if (buffer_uptodate_or_error(bh)) {
> unlock_buffer(bh);
> return 0;
> }
> @@ -214,49 +214,24 @@ int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
> return ext4_read_bh(bh, op_flags, NULL);
> }
>
> -/*
> - * This works like __bread_gfp() except it uses ERR_PTR for error
> - * returns. Currently with sb_bread it's impossible to distinguish
> - * between ENOMEM and EIO situations (since both result in a NULL
> - * return.
> - */
> -static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
> - sector_t block,
> - blk_opf_t op_flags, gfp_t gfp)
> -{
> - struct buffer_head *bh;
> - int ret;
> -
> - bh = sb_getblk_gfp(sb, block, gfp);
> - if (bh == NULL)
> - return ERR_PTR(-ENOMEM);
> - if (ext4_buffer_uptodate(bh))
> - return bh;
> -
> - ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
> - if (ret) {
> - put_bh(bh);
> - return ERR_PTR(ret);
> - }
> - return bh;
> -}
> -
> struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
> blk_opf_t op_flags)
> {
> - gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
> - ~__GFP_FS) | __GFP_MOVABLE;
> + struct buffer_head *bh = __bread_gfp2(sb->s_bdev, block,
> + sb->s_blocksize,
> + REQ_META | op_flags,
> + __GFP_MOVABLE);
>
> - return __ext4_sb_bread_gfp(sb, block, op_flags, gfp);
> + return bh ? bh : ERR_PTR(-EIO);
> }
>
> struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
> sector_t block)
> {
> - gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
> - ~__GFP_FS);
> + struct buffer_head *bh = __bread_gfp2(sb->s_bdev, block,
> + sb->s_blocksize, 0, 0);
>
> - return __ext4_sb_bread_gfp(sb, block, 0, gfp);
> + return bh ? bh : ERR_PTR(-EIO);
> }
>
> void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
> diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c
> index 75bf1f88843c..49e918221aac 100644
> --- a/fs/ext4/symlink.c
> +++ b/fs/ext4/symlink.c
> @@ -94,7 +94,7 @@ static const char *ext4_get_link(struct dentry *dentry, struct inode *inode,
> bh = ext4_getblk(NULL, inode, 0, EXT4_GET_BLOCKS_CACHED_NOWAIT);
> if (IS_ERR(bh))
> return ERR_CAST(bh);
> - if (!bh || !ext4_buffer_uptodate(bh))
> + if (!bh || !buffer_uptodate_or_error(bh))
> return ERR_PTR(-ECHILD);
> } else {
> bh = ext4_bread(NULL, inode, 0, 0);
> --
> 2.39.2
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR