Re: [PATCH 1/5] fat: remove parent_logstart check in fat_get_parent

[OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>]

Namjae Jeon <linkinjeon@gmail.com> writes:

> From: Namjae Jeon <namjae.jeon@samsung.com>
>
> The root directory inode is added to the directory hash table in
> fat_attach when mounted with nfs option. Since root dentry never
> expires until umount, fat_dget never fails to return the root inode
> for subdirectories of root inode.i.e., parent_logstart cannot be zero.

Sorry, I will review at this weekend.

Thanks.

> Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
> Signed-off-by: Ravishankar N <ravi.n1@samsung.com>
> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
> ---
>  fs/fat/nfs.c |   51 ++++++++++++++++++++++-----------------------------
>  1 file changed, 22 insertions(+), 29 deletions(-)
>
> diff --git a/fs/fat/nfs.c b/fs/fat/nfs.c
> index a4e6ac7..671a75d 100644
> --- a/fs/fat/nfs.c
> +++ b/fs/fat/nfs.c
> @@ -274,36 +274,29 @@ struct dentry *fat_get_parent(struct dentry *child_dir)
>  		parent_inode = fat_dget(sb, parent_logstart);
>  		if (parent_inode || sbi->options.nfs != FAT_NFS_NOSTALE_RO)
>  			goto out;
> -		if (!parent_logstart)
> -			/*logstart of dotdot entry is zero if
> -			* if the directory's parent is root
> -			*/
> -			parent_inode = sb->s_root->d_inode;
> -		else {
> -			blknr = fat_clus_to_blknr(sbi, parent_logstart);
> -			parent_bh = sb_bread(sb, blknr);
> -			if (!parent_bh) {
> -				fat_msg(sb, KERN_ERR,
> -					"NFS:unable to read cluster of parent directory");
> -				goto out;
> -			}
> -			de = (struct msdos_dir_entry *) parent_bh->b_data;
> -			clus_to_match = fat_get_start(sbi, &de[0]);
> -			search_clus = fat_get_start(sbi, &de[1]);
> -			if (!search_clus)
> -				search_clus = sbi->root_cluster;
> -			brelse(parent_bh);
> -			do {
> -				parent_inode =  fat_traverse_cluster(sb,
> -						search_clus, clus_to_match);
> -				if (IS_ERR(parent_inode) || parent_inode)
> -					break;
> -				search_clus = fat_read_next_clus(sb,
> -								search_clus);
> -				if (search_clus < 0)
> -					break;
> -			} while (search_clus != FAT_ENT_EOF);
> +		blknr = fat_clus_to_blknr(sbi, parent_logstart);
> +		parent_bh = sb_bread(sb, blknr);
> +		if (!parent_bh) {
> +			fat_msg(sb, KERN_ERR,
> +				"NFS:unable to read cluster of parent directory");
> +			goto out;
>  		}
> +		de = (struct msdos_dir_entry *) parent_bh->b_data;
> +		clus_to_match = fat_get_start(sbi, &de[0]);
> +		search_clus = fat_get_start(sbi, &de[1]);
> +		if (!search_clus)
> +			search_clus = sbi->root_cluster;
> +		brelse(parent_bh);
> +		do {
> +			parent_inode =  fat_traverse_cluster(sb,
> +					search_clus, clus_to_match);
> +			if (IS_ERR(parent_inode) || parent_inode)
> +				break;
> +			search_clus = fat_read_next_clus(sb,
> +							search_clus);
> +			if (search_clus < 0)
> +				break;
> +		} while (search_clus != FAT_ENT_EOF);
>  	}
>  out:
>  	brelse(dotdot_bh);

-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>