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

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

[Namjae Jeon]

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.

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);
-- 
1.7.9.5

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

[OGAWA Hirofumi]

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>

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

[Namjae Jeon]

2012/10/31, 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.
No problem, Thank you.
>
> 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>
>

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

[OGAWA Hirofumi]

Namjae Jeon <linkinjeon@gmail.com> writes:

> +		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);

I started to understand what is doing this with cleanup. It is really
strange and duplicates many codes with bugs.

So, please replace whole FAT nfs patches in -mm to review whole at next
patchset. And sorry, but please think whole more carefully.

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

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

[Namjae Jeon]

2012/11/5, OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>:
> Namjae Jeon <linkinjeon@gmail.com> writes:
>
>> +		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);
>
> I started to understand what is doing this with cleanup. It is really
> strange and duplicates many codes with bugs.
>
> So, please replace whole FAT nfs patches in -mm to review whole at next
> patchset. And sorry, but please think whole more carefully.
Hi OGAWA.
Okay, I will rework all of patches as your comment.
Thanks for review.
>
> Thanks.
> --
> OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
>