2024-04-09 08:12:51

by Hongzhen Luo

Subject: [PATCH] erofs: derive fsid from on-disk UUID for .statfs() if possible

Use the superblock's UUID to generate the fsid when it's non-null.

Signed-off-by: Hongzhen Luo <[email protected]>
---
fs/erofs/super.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index c0eb139adb07..83bd8ee3b5ba 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -923,22 +923,20 @@ static int erofs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
struct erofs_sb_info *sbi = EROFS_SB(sb);
- u64 id = 0;
-
- if (!erofs_is_fscache_mode(sb))
- id = huge_encode_dev(sb->s_bdev->bd_dev);

buf->f_type = sb->s_magic;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = sbi->total_blocks;
buf->f_bfree = buf->f_bavail = 0;
-
buf->f_files = ULLONG_MAX;
buf->f_ffree = ULLONG_MAX - sbi->inos;
-
buf->f_namelen = EROFS_NAME_LEN;

- buf->f_fsid = u64_to_fsid(id);
+ if (uuid_is_null(&sb->s_uuid))
+ buf->f_fsid = u64_to_fsid(erofs_is_fscache_mode(sb) ? 0 :
+ huge_encode_dev(sb->s_bdev->bd_dev));
+ else
+ buf->f_fsid = uuid_to_fsid((__u8 *)&sb->s_uuid);
return 0;
}

--
2.37.1

2024-04-09 08:48:05

by Gao Xiang

Subject: Re: [PATCH] erofs: derive fsid from on-disk UUID for .statfs() if possible

On 2024/4/9 16:11, Hongzhen Luo wrote:
> Use the superblock's UUID to generate the fsid when it's non-null.
>
> Signed-off-by: Hongzhen Luo <[email protected]>

Reviewed-by: Gao Xiang <[email protected]>

Thanks,
Gao Xiang

> ---
> fs/erofs/super.c | 12 +++++-------
> 1 file changed, 5 insertions(+), 7 deletions(-)
>
> diff --git a/fs/erofs/super.c b/fs/erofs/super.c
> index c0eb139adb07..83bd8ee3b5ba 100644
> --- a/fs/erofs/super.c
> +++ b/fs/erofs/super.c
> @@ -923,22 +923,20 @@ static int erofs_statfs(struct dentry *dentry, struct kstatfs *buf)
> {
> struct super_block *sb = dentry->d_sb;
> struct erofs_sb_info *sbi = EROFS_SB(sb);
> - u64 id = 0;
> -
> - if (!erofs_is_fscache_mode(sb))
> - id = huge_encode_dev(sb->s_bdev->bd_dev);
>
> buf->f_type = sb->s_magic;
> buf->f_bsize = sb->s_blocksize;
> buf->f_blocks = sbi->total_blocks;
> buf->f_bfree = buf->f_bavail = 0;
> -
> buf->f_files = ULLONG_MAX;
> buf->f_ffree = ULLONG_MAX - sbi->inos;
> -
> buf->f_namelen = EROFS_NAME_LEN;
>
> - buf->f_fsid = u64_to_fsid(id);
> + if (uuid_is_null(&sb->s_uuid))
> + buf->f_fsid = u64_to_fsid(erofs_is_fscache_mode(sb) ? 0 :
> + huge_encode_dev(sb->s_bdev->bd_dev));
> + else
> + buf->f_fsid = uuid_to_fsid((__u8 *)&sb->s_uuid);
> return 0;
> }
>

2024-04-09 09:36:50

by Jingbo Xu

Subject: Re: [PATCH] erofs: derive fsid from on-disk UUID for .statfs() if possible

On 4/9/24 4:11 PM, Hongzhen Luo wrote:
> Use the superblock's UUID to generate the fsid when it's non-null.
>
> Signed-off-by: Hongzhen Luo <[email protected]>
> ---
> fs/erofs/super.c | 12 +++++-------
> 1 file changed, 5 insertions(+), 7 deletions(-)
>
> diff --git a/fs/erofs/super.c b/fs/erofs/super.c
> index c0eb139adb07..83bd8ee3b5ba 100644
> --- a/fs/erofs/super.c
> +++ b/fs/erofs/super.c
> @@ -923,22 +923,20 @@ static int erofs_statfs(struct dentry *dentry, struct kstatfs *buf)
> {
> struct super_block *sb = dentry->d_sb;
> struct erofs_sb_info *sbi = EROFS_SB(sb);
> - u64 id = 0;
> -
> - if (!erofs_is_fscache_mode(sb))
> - id = huge_encode_dev(sb->s_bdev->bd_dev);
>
> buf->f_type = sb->s_magic;
> buf->f_bsize = sb->s_blocksize;
> buf->f_blocks = sbi->total_blocks;
> buf->f_bfree = buf->f_bavail = 0;
> -
> buf->f_files = ULLONG_MAX;
> buf->f_ffree = ULLONG_MAX - sbi->inos;
> -
> buf->f_namelen = EROFS_NAME_LEN;
>
> - buf->f_fsid = u64_to_fsid(id);
> + if (uuid_is_null(&sb->s_uuid))
> + buf->f_fsid = u64_to_fsid(erofs_is_fscache_mode(sb) ? 0 :
> + huge_encode_dev(sb->s_bdev->bd_dev));
> + else
> + buf->f_fsid = uuid_to_fsid((__u8 *)&sb->s_uuid);

How about

buf->f_fsid = uuid_to_fsid(sb->s_uuid.b);

which looks cleaner.

Otherwise LGTM.

Reviewed-by: Jingbo Xu <[email protected]>



--
Thanks,
Jingbo

2024-04-09 11:23:31

by Hongzhen Luo

Subject: Re: [PATCH] erofs: derive fsid from on-disk UUID for .statfs() if possible

在 2024/4/9 17:36, Jingbo Xu 写道:
>
> On 4/9/24 4:11 PM, Hongzhen Luo wrote:
>> Use the superblock's UUID to generate the fsid when it's non-null.
>>
>> Signed-off-by: Hongzhen Luo <[email protected]>
>> ---
>> fs/erofs/super.c | 12 +++++-------
>> 1 file changed, 5 insertions(+), 7 deletions(-)
>>
>> diff --git a/fs/erofs/super.c b/fs/erofs/super.c
>> index c0eb139adb07..83bd8ee3b5ba 100644
>> --- a/fs/erofs/super.c
>> +++ b/fs/erofs/super.c
>> @@ -923,22 +923,20 @@ static int erofs_statfs(struct dentry *dentry, struct kstatfs *buf)
>> {
>> struct super_block *sb = dentry->d_sb;
>> struct erofs_sb_info *sbi = EROFS_SB(sb);
>> - u64 id = 0;
>> -
>> - if (!erofs_is_fscache_mode(sb))
>> - id = huge_encode_dev(sb->s_bdev->bd_dev);
>>
>> buf->f_type = sb->s_magic;
>> buf->f_bsize = sb->s_blocksize;
>> buf->f_blocks = sbi->total_blocks;
>> buf->f_bfree = buf->f_bavail = 0;
>> -
>> buf->f_files = ULLONG_MAX;
>> buf->f_ffree = ULLONG_MAX - sbi->inos;
>> -
>> buf->f_namelen = EROFS_NAME_LEN;
>>
>> - buf->f_fsid = u64_to_fsid(id);
>> + if (uuid_is_null(&sb->s_uuid))
>> + buf->f_fsid = u64_to_fsid(erofs_is_fscache_mode(sb) ? 0 :
>> + huge_encode_dev(sb->s_bdev->bd_dev));
>> + else
>> + buf->f_fsid = uuid_to_fsid((__u8 *)&sb->s_uuid);
> How about
>
> buf->f_fsid = uuid_to_fsid(sb->s_uuid.b);
>
> which looks cleaner.
>
> Otherwise LGTM.
>
> Reviewed-by: Jingbo Xu <[email protected]>
>
>
Thanks. I will send v2 later.

---

Hongzhen