* [PATCH] mount: avoid po_destroy to modify errno what we really want
@ 2010-11-25 10:07 Mi Jinlong
2010-11-29 14:45 ` Chuck Lever
0 siblings, 1 reply; 6+ messages in thread
From: Mi Jinlong @ 2010-11-25 10:07 UTC (permalink / raw)
To: Steve Dickson; +Cc: NFSv3 list
We should return the errno that was set before po_destroy,
rather than the errno that was set at po_destroy.
Because the po_destroy function don't affect the return value,
this patch just revert the saved errno after po_destroy.
Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
---
utils/mount/stropts.c | 8 ++++++--
1 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
index 50a1a2a..d554877 100644
--- a/utils/mount/stropts.c
+++ b/utils/mount/stropts.c
@@ -592,7 +592,7 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
struct sockaddr *sap, socklen_t salen)
{
struct mount_options *options = po_dup(mi->options);
- int result = 0;
+ int result = 0, save = 0;
if (!options) {
errno = ENOMEM;
@@ -637,7 +637,9 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
result = nfs_sys_mount(mi, options);
out_fail:
+ save = errno;
po_destroy(options);
+ errno = save;
return result;
}
@@ -673,7 +675,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
struct sockaddr *sap, socklen_t salen)
{
struct mount_options *options = po_dup(mi->options);
- int result = 0;
+ int result = 0, save = 0;
if (!options) {
errno = ENOMEM;
@@ -724,7 +726,9 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
result = nfs_sys_mount(mi, options);
out_fail:
+ save = errno;
po_destroy(options);
+ errno = save;
return result;
}
--
1.7.3.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] mount: avoid po_destroy to modify errno what we really want
2010-11-25 10:07 [PATCH] mount: avoid po_destroy to modify errno what we really want Mi Jinlong
@ 2010-11-29 14:45 ` Chuck Lever
2010-11-29 15:20 ` Steve Dickson
0 siblings, 1 reply; 6+ messages in thread
From: Chuck Lever @ 2010-11-29 14:45 UTC (permalink / raw)
To: Mi Jinlong; +Cc: Steve Dickson, NFSv3 list
On Nov 25, 2010, at 5:07 AM, Mi Jinlong wrote:
> We should return the errno that was set before po_destroy,
> rather than the errno that was set at po_destroy.
>
> Because the po_destroy function don't affect the return value,
> this patch just revert the saved errno after po_destroy.
The only library function used in po_destroy() is free(3). Does free(3) change the value of errno?
> Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
> Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
> ---
> utils/mount/stropts.c | 8 ++++++--
> 1 files changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
> index 50a1a2a..d554877 100644
> --- a/utils/mount/stropts.c
> +++ b/utils/mount/stropts.c
> @@ -592,7 +592,7 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
> struct sockaddr *sap, socklen_t salen)
> {
> struct mount_options *options = po_dup(mi->options);
> - int result = 0;
> + int result = 0, save = 0;
>
> if (!options) {
> errno = ENOMEM;
> @@ -637,7 +637,9 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
> result = nfs_sys_mount(mi, options);
>
> out_fail:
> + save = errno;
> po_destroy(options);
> + errno = save;
> return result;
> }
>
> @@ -673,7 +675,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
> struct sockaddr *sap, socklen_t salen)
> {
> struct mount_options *options = po_dup(mi->options);
> - int result = 0;
> + int result = 0, save = 0;
>
> if (!options) {
> errno = ENOMEM;
> @@ -724,7 +726,9 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
> result = nfs_sys_mount(mi, options);
>
> out_fail:
> + save = errno;
> po_destroy(options);
> + errno = save;
> return result;
> }
>
> --
> 1.7.3.2
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Chuck Lever
chuck[dot]lever[at]oracle[dot]com
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] mount: avoid po_destroy to modify errno what we really want
2010-11-29 14:45 ` Chuck Lever
@ 2010-11-29 15:20 ` Steve Dickson
2010-11-30 2:05 ` Bian Naimeng
0 siblings, 1 reply; 6+ messages in thread
From: Steve Dickson @ 2010-11-29 15:20 UTC (permalink / raw)
To: Chuck Lever; +Cc: Mi Jinlong, NFSv3 list
On 11/29/2010 09:45 AM, Chuck Lever wrote:
>
> On Nov 25, 2010, at 5:07 AM, Mi Jinlong wrote:
>
>> We should return the errno that was set before po_destroy,
>> rather than the errno that was set at po_destroy.
>>
>> Because the po_destroy function don't affect the return value,
>> this patch just revert the saved errno after po_destroy.
>
> The only library function used in po_destroy() is free(3).
> Does free(3) change the value of errno?
Looking at the man page and taking a look a the
glibc code it appears the answer is no. free(3)
does not set errno.
Bian, what was the problem you were seeing that this
patch fixed?
steved.
>
>> Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
>> Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
>> ---
>> utils/mount/stropts.c | 8 ++++++--
>> 1 files changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
>> index 50a1a2a..d554877 100644
>> --- a/utils/mount/stropts.c
>> +++ b/utils/mount/stropts.c
>> @@ -592,7 +592,7 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>> struct sockaddr *sap, socklen_t salen)
>> {
>> struct mount_options *options = po_dup(mi->options);
>> - int result = 0;
>> + int result = 0, save = 0;
>>
>> if (!options) {
>> errno = ENOMEM;
>> @@ -637,7 +637,9 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>> result = nfs_sys_mount(mi, options);
>>
>> out_fail:
>> + save = errno;
>> po_destroy(options);
>> + errno = save;
>> return result;
>> }
>>
>> @@ -673,7 +675,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>> struct sockaddr *sap, socklen_t salen)
>> {
>> struct mount_options *options = po_dup(mi->options);
>> - int result = 0;
>> + int result = 0, save = 0;
>>
>> if (!options) {
>> errno = ENOMEM;
>> @@ -724,7 +726,9 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>> result = nfs_sys_mount(mi, options);
>>
>> out_fail:
>> + save = errno;
>> po_destroy(options);
>> + errno = save;
>> return result;
>> }
>>
>> --
>> 1.7.3.2
>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] mount: avoid po_destroy to modify errno what we really want
2010-11-29 15:20 ` Steve Dickson
@ 2010-11-30 2:05 ` Bian Naimeng
2010-11-30 15:11 ` Chuck Lever
0 siblings, 1 reply; 6+ messages in thread
From: Bian Naimeng @ 2010-11-30 2:05 UTC (permalink / raw)
To: Steve Dickson; +Cc: Chuck Lever, Mi Jinlong, NFSv3 list
Steve Dickson wrote:
>
> On 11/29/2010 09:45 AM, Chuck Lever wrote:
>> On Nov 25, 2010, at 5:07 AM, Mi Jinlong wrote:
>>
>>> We should return the errno that was set before po_destroy,
>>> rather than the errno that was set at po_destroy.
>>>
>>> Because the po_destroy function don't affect the return value,
>>> this patch just revert the saved errno after po_destroy.
>> The only library function used in po_destroy() is free(3).
>> Does free(3) change the value of errno?
> Looking at the man page and taking a look a the
> glibc code it appears the answer is no. free(3)
> does not set errno.
>
> Bian, what was the problem you were seeing that this
> patch fixed?
>
Actually, there's no problem now. But this's not a good style, po_destroy
maybe change the errno later on such as adding a printf.
So if somebady want modify the po_destroy, he must be careful of it. :)
And, i don't think it's a good idea that explicitly set errno, it maybe make
some trouble in the future. It's better returning error in nfs_do_mount_v3v2,
or save the error in a input parameter. :)
Thanks
Bian
> steved.
>
>>> Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
>>> Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
>>> ---
>>> utils/mount/stropts.c | 8 ++++++--
>>> 1 files changed, 6 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
>>> index 50a1a2a..d554877 100644
>>> --- a/utils/mount/stropts.c
>>> +++ b/utils/mount/stropts.c
>>> @@ -592,7 +592,7 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>>> struct sockaddr *sap, socklen_t salen)
>>> {
>>> struct mount_options *options = po_dup(mi->options);
>>> - int result = 0;
>>> + int result = 0, save = 0;
>>>
>>> if (!options) {
>>> errno = ENOMEM;
>>> @@ -637,7 +637,9 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>>> result = nfs_sys_mount(mi, options);
>>>
>>> out_fail:
>>> + save = errno;
>>> po_destroy(options);
>>> + errno = save;
>>> return result;
>>> }
>>>
>>> @@ -673,7 +675,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>>> struct sockaddr *sap, socklen_t salen)
>>> {
>>> struct mount_options *options = po_dup(mi->options);
>>> - int result = 0;
>>> + int result = 0, save = 0;
>>>
>>> if (!options) {
>>> errno = ENOMEM;
>>> @@ -724,7 +726,9 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>>> result = nfs_sys_mount(mi, options);
>>>
>>> out_fail:
>>> + save = errno;
>>> po_destroy(options);
>>> + errno = save;
>>> return result;
>>> }
>>>
>>> --
>>> 1.7.3.2
>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
>
--
Regards
Bian Naimeng
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] mount: avoid po_destroy to modify errno what we really want
2010-11-30 2:05 ` Bian Naimeng
@ 2010-11-30 15:11 ` Chuck Lever
2010-12-01 1:01 ` Bian Naimeng
0 siblings, 1 reply; 6+ messages in thread
From: Chuck Lever @ 2010-11-30 15:11 UTC (permalink / raw)
To: Bian Naimeng; +Cc: Steve Dickson, Mi Jinlong, NFSv3 list
Hi Bian
On Nov 29, 2010, at 9:05 PM, Bian Naimeng wrote:
>
>
> Steve Dickson wrote:
>>
>> On 11/29/2010 09:45 AM, Chuck Lever wrote:
>>> On Nov 25, 2010, at 5:07 AM, Mi Jinlong wrote:
>>>
>>>> We should return the errno that was set before po_destroy,
>>>> rather than the errno that was set at po_destroy.
>>>>
>>>> Because the po_destroy function don't affect the return value,
>>>> this patch just revert the saved errno after po_destroy.
>>> The only library function used in po_destroy() is free(3).
>>> Does free(3) change the value of errno?
>> Looking at the man page and taking a look a the
>> glibc code it appears the answer is no. free(3)
>> does not set errno.
>>
>> Bian, what was the problem you were seeing that this
>> patch fixed?
>>
>
> Actually, there's no problem now. But this's not a good style, po_destroy
> maybe change the errno later on such as adding a printf.
> So if somebady want modify the po_destroy, he must be careful of it. :)
>
> And, i don't think it's a good idea that explicitly set errno, it maybe make
> some trouble in the future. It's better returning error in nfs_do_mount_v3v2,
> or save the error in a input parameter. :)
Perhaps it isn't good style, but I'd rather see all of stropts.c updated to pass errno as an explicit parameter than to have it changed piecemeal. I agree that we run into trouble everywhere in mount with errno.
I think this particular patch is unnecessary until we have a need for it. Basically it confuses a reviewer who sees that we've gone to the trouble here to save and restore errno, but nowhere else, and besides po_destroy() doesn't even alter errno. Why are we bothering?
> Thanks
> Bian
>
>> steved.
>>
>>>> Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
>>>> Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
>>>> ---
>>>> utils/mount/stropts.c | 8 ++++++--
>>>> 1 files changed, 6 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
>>>> index 50a1a2a..d554877 100644
>>>> --- a/utils/mount/stropts.c
>>>> +++ b/utils/mount/stropts.c
>>>> @@ -592,7 +592,7 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>>>> struct sockaddr *sap, socklen_t salen)
>>>> {
>>>> struct mount_options *options = po_dup(mi->options);
>>>> - int result = 0;
>>>> + int result = 0, save = 0;
>>>>
>>>> if (!options) {
>>>> errno = ENOMEM;
>>>> @@ -637,7 +637,9 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>>>> result = nfs_sys_mount(mi, options);
>>>>
>>>> out_fail:
>>>> + save = errno;
>>>> po_destroy(options);
>>>> + errno = save;
>>>> return result;
>>>> }
>>>>
>>>> @@ -673,7 +675,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>>>> struct sockaddr *sap, socklen_t salen)
>>>> {
>>>> struct mount_options *options = po_dup(mi->options);
>>>> - int result = 0;
>>>> + int result = 0, save = 0;
>>>>
>>>> if (!options) {
>>>> errno = ENOMEM;
>>>> @@ -724,7 +726,9 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>>>> result = nfs_sys_mount(mi, options);
>>>>
>>>> out_fail:
>>>> + save = errno;
>>>> po_destroy(options);
>>>> + errno = save;
>>>> return result;
>>>> }
>>>>
>>>> --
>>>> 1.7.3.2
>>>>
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>
>>
>
> --
> Regards
> Bian Naimeng
>
--
Chuck Lever
chuck[dot]lever[at]oracle[dot]com
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] mount: avoid po_destroy to modify errno what we really want
2010-11-30 15:11 ` Chuck Lever
@ 2010-12-01 1:01 ` Bian Naimeng
0 siblings, 0 replies; 6+ messages in thread
From: Bian Naimeng @ 2010-12-01 1:01 UTC (permalink / raw)
To: Chuck Lever; +Cc: Steve Dickson, Mi Jinlong, NFSv3 list
Chuck Lever wrote:
> Hi Bian
>
> On Nov 29, 2010, at 9:05 PM, Bian Naimeng wrote:
>
>>
>> Steve Dickson wrote:
>>> On 11/29/2010 09:45 AM, Chuck Lever wrote:
>>>> On Nov 25, 2010, at 5:07 AM, Mi Jinlong wrote:
>>>>
>>>>> We should return the errno that was set before po_destroy,
>>>>> rather than the errno that was set at po_destroy.
>>>>>
>>>>> Because the po_destroy function don't affect the return value,
>>>>> this patch just revert the saved errno after po_destroy.
>>>> The only library function used in po_destroy() is free(3).
>>>> Does free(3) change the value of errno?
>>> Looking at the man page and taking a look a the
>>> glibc code it appears the answer is no. free(3)
>>> does not set errno.
>>>
>>> Bian, what was the problem you were seeing that this
>>> patch fixed?
>>>
>> Actually, there's no problem now. But this's not a good style, po_destroy
>> maybe change the errno later on such as adding a printf.
>> So if somebady want modify the po_destroy, he must be careful of it. :)
>>
>> And, i don't think it's a good idea that explicitly set errno, it maybe make
>> some trouble in the future. It's better returning error in nfs_do_mount_v3v2,
>> or save the error in a input parameter. :)
>
> Perhaps it isn't good style, but I'd rather see all of stropts.c updated to pass errno as an explicit parameter than to have it changed piecemeal. I agree that we run into trouble everywhere in mount with errno.
>
> I think this particular patch is unnecessary until we have a need for it. Basically it confuses a reviewer who sees that we've gone to the trouble here to save and restore errno, but nowhere else, and besides po_destroy() doesn't even alter errno. Why are we bothering?
>
Well, it's okay to me.
Thanks
Bian
>>> steved.
>>>
>>>>> Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
>>>>> Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
>>>>> ---
>>>>> utils/mount/stropts.c | 8 ++++++--
>>>>> 1 files changed, 6 insertions(+), 2 deletions(-)
>>>>>
>>>>> diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
>>>>> index 50a1a2a..d554877 100644
>>>>> --- a/utils/mount/stropts.c
>>>>> +++ b/utils/mount/stropts.c
>>>>> @@ -592,7 +592,7 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>>>>> struct sockaddr *sap, socklen_t salen)
>>>>> {
>>>>> struct mount_options *options = po_dup(mi->options);
>>>>> - int result = 0;
>>>>> + int result = 0, save = 0;
>>>>>
>>>>> if (!options) {
>>>>> errno = ENOMEM;
>>>>> @@ -637,7 +637,9 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>>>>> result = nfs_sys_mount(mi, options);
>>>>>
>>>>> out_fail:
>>>>> + save = errno;
>>>>> po_destroy(options);
>>>>> + errno = save;
>>>>> return result;
>>>>> }
>>>>>
>>>>> @@ -673,7 +675,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>>>>> struct sockaddr *sap, socklen_t salen)
>>>>> {
>>>>> struct mount_options *options = po_dup(mi->options);
>>>>> - int result = 0;
>>>>> + int result = 0, save = 0;
>>>>>
>>>>> if (!options) {
>>>>> errno = ENOMEM;
>>>>> @@ -724,7 +726,9 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>>>>> result = nfs_sys_mount(mi, options);
>>>>>
>>>>> out_fail:
>>>>> + save = errno;
>>>>> po_destroy(options);
>>>>> + errno = save;
>>>>> return result;
>>>>> }
>>>>>
>>>>> --
>>>>> 1.7.3.2
>>>>>
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>>
>>>
>> --
>> Regards
>> Bian Naimeng
>>
>
--
Regards
Bian Naimeng
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2010-12-01 1:01 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-11-25 10:07 [PATCH] mount: avoid po_destroy to modify errno what we really want Mi Jinlong
2010-11-29 14:45 ` Chuck Lever
2010-11-29 15:20 ` Steve Dickson
2010-11-30 2:05 ` Bian Naimeng
2010-11-30 15:11 ` Chuck Lever
2010-12-01 1:01 ` Bian Naimeng
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).