diff mbox series

[3/3] xfs: only do dqget or dqhold for the specified dquots

Message ID 1600765442-12146-4-git-send-email-kaixuxia@tencent.com (mailing list archive)
State New, archived
Headers show
Series xfs: random fixes for disk quota | expand

Commit Message

Kaixu Xia Sept. 22, 2020, 9:04 a.m. UTC 
From: Kaixu Xia <kaixuxia@tencent.com>

We attach the dquot(s) to the given inode and return udquot, gdquot
or pdquot with references taken by dqget or dqhold in xfs_qm_vop_dqalloc()
funciton. Actually, we only need to do dqget or dqhold for the specified
dquots, it is unnecessary if the passed-in O_{u,g,p}dqpp value is NULL.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
---
 fs/xfs/xfs_qm.c | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

Comments

Darrick J. Wong Sept. 22, 2020, 4:18 p.m. UTC | #1 
On Tue, Sep 22, 2020 at 05:04:02PM +0800, xiakaixu1987@gmail.com wrote:
> From: Kaixu Xia <kaixuxia@tencent.com>
> 
> We attach the dquot(s) to the given inode and return udquot, gdquot
> or pdquot with references taken by dqget or dqhold in xfs_qm_vop_dqalloc()
> funciton. Actually, we only need to do dqget or dqhold for the specified
> dquots, it is unnecessary if the passed-in O_{u,g,p}dqpp value is NULL.

When would a caller pass in (for example) XFS_QMOPT_UQUOTA, a different
uid than the one currently associated with the inode, but a null
O_udqpp?  It doesn't make sense to say "Prepare to change this file's
uid, but don't give me the dquot of the new uid."

None of the callers do that today, so I don't see the point of this
patch.  Perhaps the function could ASSERT the arguments a little more
closely?

--D

> Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
> ---
>  fs/xfs/xfs_qm.c | 13 ++++---------
>  1 file changed, 4 insertions(+), 9 deletions(-)
> 
> diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
> index 44509decb4cd..38380fc29b4d 100644
> --- a/fs/xfs/xfs_qm.c
> +++ b/fs/xfs/xfs_qm.c
> @@ -1661,7 +1661,7 @@ xfs_qm_vop_dqalloc(
>  		}
>  	}
>  
> -	if ((flags & XFS_QMOPT_UQUOTA) && XFS_IS_UQUOTA_ON(mp)) {
> +	if ((flags & XFS_QMOPT_UQUOTA) && XFS_IS_UQUOTA_ON(mp) && O_udqpp) {
>  		if (!uid_eq(inode->i_uid, uid)) {
>  			/*
>  			 * What we need is the dquot that has this uid, and
> @@ -1694,7 +1694,7 @@ xfs_qm_vop_dqalloc(
>  			uq = xfs_qm_dqhold(ip->i_udquot);
>  		}
>  	}
> -	if ((flags & XFS_QMOPT_GQUOTA) && XFS_IS_GQUOTA_ON(mp)) {
> +	if ((flags & XFS_QMOPT_GQUOTA) && XFS_IS_GQUOTA_ON(mp) && O_gdqpp) {
>  		if (!gid_eq(inode->i_gid, gid)) {
>  			xfs_iunlock(ip, lockflags);
>  			error = xfs_qm_dqget(mp, from_kgid(user_ns, gid),
> @@ -1711,7 +1711,7 @@ xfs_qm_vop_dqalloc(
>  			gq = xfs_qm_dqhold(ip->i_gdquot);
>  		}
>  	}
> -	if ((flags & XFS_QMOPT_PQUOTA) && XFS_IS_PQUOTA_ON(mp)) {
> +	if ((flags & XFS_QMOPT_PQUOTA) && XFS_IS_PQUOTA_ON(mp) && O_pdqpp) {
>  		if (ip->i_d.di_projid != prid) {
>  			xfs_iunlock(ip, lockflags);
>  			error = xfs_qm_dqget(mp, prid,
> @@ -1733,16 +1733,11 @@ xfs_qm_vop_dqalloc(
>  	xfs_iunlock(ip, lockflags);
>  	if (O_udqpp)
>  		*O_udqpp = uq;
> -	else
> -		xfs_qm_dqrele(uq);
>  	if (O_gdqpp)
>  		*O_gdqpp = gq;
> -	else
> -		xfs_qm_dqrele(gq);
>  	if (O_pdqpp)
>  		*O_pdqpp = pq;
> -	else
> -		xfs_qm_dqrele(pq);
> +
>  	return 0;
>  
>  error_rele:
> -- 
> 2.20.0
>
Kaixu Xia Sept. 23, 2020, 3:11 a.m. UTC | #2 
On 2020/9/23 0:18, Darrick J. Wong wrote:
> On Tue, Sep 22, 2020 at 05:04:02PM +0800, xiakaixu1987@gmail.com wrote:
>> From: Kaixu Xia <kaixuxia@tencent.com>
>>
>> We attach the dquot(s) to the given inode and return udquot, gdquot
>> or pdquot with references taken by dqget or dqhold in xfs_qm_vop_dqalloc()
>> funciton. Actually, we only need to do dqget or dqhold for the specified
>> dquots, it is unnecessary if the passed-in O_{u,g,p}dqpp value is NULL.
> 
> When would a caller pass in (for example) XFS_QMOPT_UQUOTA, a different
> uid than the one currently associated with the inode, but a null
> O_udqpp?  It doesn't make sense to say "Prepare to change this file's
> uid, but don't give me the dquot of the new uid."
> 
> None of the callers do that today, so I don't see the point of this
> patch.  Perhaps the function could ASSERT the arguments a little more
> closely?

Yeah, ASSERT the arguments is better, will do that in the next version.

Thanks,
Kaixu
 
> 
> --D
> 
>> Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
>> ---
>>  fs/xfs/xfs_qm.c | 13 ++++---------
>>  1 file changed, 4 insertions(+), 9 deletions(-)
>>
>> diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
>> index 44509decb4cd..38380fc29b4d 100644
>> --- a/fs/xfs/xfs_qm.c
>> +++ b/fs/xfs/xfs_qm.c
>> @@ -1661,7 +1661,7 @@ xfs_qm_vop_dqalloc(
>>  		}
>>  	}
>>  
>> -	if ((flags & XFS_QMOPT_UQUOTA) && XFS_IS_UQUOTA_ON(mp)) {
>> +	if ((flags & XFS_QMOPT_UQUOTA) && XFS_IS_UQUOTA_ON(mp) && O_udqpp) {
>>  		if (!uid_eq(inode->i_uid, uid)) {
>>  			/*
>>  			 * What we need is the dquot that has this uid, and
>> @@ -1694,7 +1694,7 @@ xfs_qm_vop_dqalloc(
>>  			uq = xfs_qm_dqhold(ip->i_udquot);
>>  		}
>>  	}
>> -	if ((flags & XFS_QMOPT_GQUOTA) && XFS_IS_GQUOTA_ON(mp)) {
>> +	if ((flags & XFS_QMOPT_GQUOTA) && XFS_IS_GQUOTA_ON(mp) && O_gdqpp) {
>>  		if (!gid_eq(inode->i_gid, gid)) {
>>  			xfs_iunlock(ip, lockflags);
>>  			error = xfs_qm_dqget(mp, from_kgid(user_ns, gid),
>> @@ -1711,7 +1711,7 @@ xfs_qm_vop_dqalloc(
>>  			gq = xfs_qm_dqhold(ip->i_gdquot);
>>  		}
>>  	}
>> -	if ((flags & XFS_QMOPT_PQUOTA) && XFS_IS_PQUOTA_ON(mp)) {
>> +	if ((flags & XFS_QMOPT_PQUOTA) && XFS_IS_PQUOTA_ON(mp) && O_pdqpp) {
>>  		if (ip->i_d.di_projid != prid) {
>>  			xfs_iunlock(ip, lockflags);
>>  			error = xfs_qm_dqget(mp, prid,
>> @@ -1733,16 +1733,11 @@ xfs_qm_vop_dqalloc(
>>  	xfs_iunlock(ip, lockflags);
>>  	if (O_udqpp)
>>  		*O_udqpp = uq;
>> -	else
>> -		xfs_qm_dqrele(uq);
>>  	if (O_gdqpp)
>>  		*O_gdqpp = gq;
>> -	else
>> -		xfs_qm_dqrele(gq);
>>  	if (O_pdqpp)
>>  		*O_pdqpp = pq;
>> -	else
>> -		xfs_qm_dqrele(pq);
>> +
>>  	return 0;
>>  
>>  error_rele:
>> -- 
>> 2.20.0
>>
diff mbox series

Patch

diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index 44509decb4cd..38380fc29b4d 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -1661,7 +1661,7 @@  xfs_qm_vop_dqalloc(
 		}
 	}
 
-	if ((flags & XFS_QMOPT_UQUOTA) && XFS_IS_UQUOTA_ON(mp)) {
+	if ((flags & XFS_QMOPT_UQUOTA) && XFS_IS_UQUOTA_ON(mp) && O_udqpp) {
 		if (!uid_eq(inode->i_uid, uid)) {
 			/*
 			 * What we need is the dquot that has this uid, and
@@ -1694,7 +1694,7 @@  xfs_qm_vop_dqalloc(
 			uq = xfs_qm_dqhold(ip->i_udquot);
 		}
 	}
-	if ((flags & XFS_QMOPT_GQUOTA) && XFS_IS_GQUOTA_ON(mp)) {
+	if ((flags & XFS_QMOPT_GQUOTA) && XFS_IS_GQUOTA_ON(mp) && O_gdqpp) {
 		if (!gid_eq(inode->i_gid, gid)) {
 			xfs_iunlock(ip, lockflags);
 			error = xfs_qm_dqget(mp, from_kgid(user_ns, gid),
@@ -1711,7 +1711,7 @@  xfs_qm_vop_dqalloc(
 			gq = xfs_qm_dqhold(ip->i_gdquot);
 		}
 	}
-	if ((flags & XFS_QMOPT_PQUOTA) && XFS_IS_PQUOTA_ON(mp)) {
+	if ((flags & XFS_QMOPT_PQUOTA) && XFS_IS_PQUOTA_ON(mp) && O_pdqpp) {
 		if (ip->i_d.di_projid != prid) {
 			xfs_iunlock(ip, lockflags);
 			error = xfs_qm_dqget(mp, prid,
@@ -1733,16 +1733,11 @@  xfs_qm_vop_dqalloc(
 	xfs_iunlock(ip, lockflags);
 	if (O_udqpp)
 		*O_udqpp = uq;
-	else
-		xfs_qm_dqrele(uq);
 	if (O_gdqpp)
 		*O_gdqpp = gq;
-	else
-		xfs_qm_dqrele(gq);
 	if (O_pdqpp)
 		*O_pdqpp = pq;
-	else
-		xfs_qm_dqrele(pq);
+
 	return 0;
 
 error_rele: