diff mbox

[RFC,1/2] exportfs: pass export option flags to the kernel when testing export

Message ID 1447865430-28434-1-git-send-email-jeff.layton@primarydata.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jeff Layton Nov. 18, 2015, 4:50 p.m. UTC
test_export takes a flag that just says whether to pass in the fsid or
not. This means that all we can test is the NFSEXP_FSIDi flag.

Instead of doing that, pass in the actual export options that we
intend to use (sometimes or'ed with NFSEXP_FSID to test whether that
might be the reason for the failure).

This allows us to test the actual export options that we plan to use,
and can allow the kernel to vet them properly before mount time.

The rationale here is a patch that I have that will add the ability
for filesystems to opt out of subtree checking when they can't
properly support it.

Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
---
 utils/exportfs/exportfs.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

Comments

Jeff Layton Nov. 18, 2015, 7:16 p.m. UTC | #1
On Wed, 18 Nov 2015 11:50:29 -0500
Jeff Layton <jlayton@poochiereds.net> wrote:

> test_export takes a flag that just says whether to pass in the fsid or
> not. This means that all we can test is the NFSEXP_FSIDi flag.
> 
> Instead of doing that, pass in the actual export options that we
> intend to use (sometimes or'ed with NFSEXP_FSID to test whether that
> might be the reason for the failure).
> 
> This allows us to test the actual export options that we plan to use,
> and can allow the kernel to vet them properly before mount time.
> 
> The rationale here is a patch that I have that will add the ability
> for filesystems to opt out of subtree checking when they can't
> properly support it.
> 
> Cc: Neil Brown <neilb@suse.de>
> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
> ---
>  utils/exportfs/exportfs.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/utils/exportfs/exportfs.c b/utils/exportfs/exportfs.c
> index c7a79a69b5d6..cac01fc25f9a 100644
> --- a/utils/exportfs/exportfs.c
> +++ b/utils/exportfs/exportfs.c
> @@ -531,7 +531,7 @@ static int can_test(void)
>  	return 1;
>  }
>  
> -static int test_export(char *path, int with_fsid)
> +static int test_export(char *path, int opts)
>  {
>  	/* beside max path, buf size should take protocol str into account */
>  	char buf[NFS_MAXPATHLEN+1+64] = { 0 };
> @@ -545,7 +545,7 @@ static int test_export(char *path, int with_fsid)
>  	qword_add(&bp, &len, path);
>  	if (len < 1)
>  		return 0;
> -	snprintf(bp, len, " 3 %d 65534 65534 0\n", with_fsid ? NFSEXP_FSID : 0);
> +	snprintf(bp, len, " 3 %d 65534 65534 0\n", opts);
>  	fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
>  	if (fd < 0)
>  		return 0;
> @@ -587,12 +587,12 @@ validate_export(nfs_export *exp)
>  
>  	if ((exp->m_export.e_flags & NFSEXP_FSID) || exp->m_export.e_uuid ||
>  	    fs_has_fsid) {
> -		if ( !test_export(path, 1)) {
> +		if ( !test_export(path, exp->m_export.e_flags)) {
>  			xlog(L_ERROR, "%s does not support NFS export", path);
>  			return;
>  		}
> -	} else if ( ! test_export(path, 0)) {
> -		if (test_export(path, 1))
> +	} else if ( ! test_export(path, exp->m_export.e_flags)) {
> +		if (test_export(path, exp->m_export.e_flags & NFSEXP_FSID))

Duh, that should of course be "exp->m_export.e_flags | NFSEXP_FSID".
I'll plan to resend after I wait a bit for others to comment. Please
don't merge this as-is though -- it obviously needs better testing.

We might be able to simplify the above logic a little too...hmmm...

>  			xlog(L_ERROR, "%s requires fsid= for NFS export", path);
>  		else
>  			xlog(L_ERROR, "%s does not support NFS export", path);
Steve Dickson Nov. 18, 2015, 7:19 p.m. UTC | #2
On 11/18/2015 02:16 PM, Jeff Layton wrote:
> On Wed, 18 Nov 2015 11:50:29 -0500
> Jeff Layton <jlayton@poochiereds.net> wrote:
> 
>> test_export takes a flag that just says whether to pass in the fsid or
>> not. This means that all we can test is the NFSEXP_FSIDi flag.
>>
>> Instead of doing that, pass in the actual export options that we
>> intend to use (sometimes or'ed with NFSEXP_FSID to test whether that
>> might be the reason for the failure).
>>
>> This allows us to test the actual export options that we plan to use,
>> and can allow the kernel to vet them properly before mount time.
>>
>> The rationale here is a patch that I have that will add the ability
>> for filesystems to opt out of subtree checking when they can't
>> properly support it.
>>
>> Cc: Neil Brown <neilb@suse.de>
>> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
>> ---
>>  utils/exportfs/exportfs.c | 10 +++++-----
>>  1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/utils/exportfs/exportfs.c b/utils/exportfs/exportfs.c
>> index c7a79a69b5d6..cac01fc25f9a 100644
>> --- a/utils/exportfs/exportfs.c
>> +++ b/utils/exportfs/exportfs.c
>> @@ -531,7 +531,7 @@ static int can_test(void)
>>  	return 1;
>>  }
>>  
>> -static int test_export(char *path, int with_fsid)
>> +static int test_export(char *path, int opts)
>>  {
>>  	/* beside max path, buf size should take protocol str into account */
>>  	char buf[NFS_MAXPATHLEN+1+64] = { 0 };
>> @@ -545,7 +545,7 @@ static int test_export(char *path, int with_fsid)
>>  	qword_add(&bp, &len, path);
>>  	if (len < 1)
>>  		return 0;
>> -	snprintf(bp, len, " 3 %d 65534 65534 0\n", with_fsid ? NFSEXP_FSID : 0);
>> +	snprintf(bp, len, " 3 %d 65534 65534 0\n", opts);
>>  	fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
>>  	if (fd < 0)
>>  		return 0;
>> @@ -587,12 +587,12 @@ validate_export(nfs_export *exp)
>>  
>>  	if ((exp->m_export.e_flags & NFSEXP_FSID) || exp->m_export.e_uuid ||
>>  	    fs_has_fsid) {
>> -		if ( !test_export(path, 1)) {
>> +		if ( !test_export(path, exp->m_export.e_flags)) {
>>  			xlog(L_ERROR, "%s does not support NFS export", path);
>>  			return;
>>  		}
>> -	} else if ( ! test_export(path, 0)) {
>> -		if (test_export(path, 1))
>> +	} else if ( ! test_export(path, exp->m_export.e_flags)) {
>> +		if (test_export(path, exp->m_export.e_flags & NFSEXP_FSID))
> 
> Duh, that should of course be "exp->m_export.e_flags | NFSEXP_FSID".
> I'll plan to resend after I wait a bit for others to comment. Please
> don't merge this as-is though -- it obviously needs better testing.
> 
> We might be able to simplify the above logic a little too...hmmm...
That logic did look a bit odd... I'll wait for the next version....

steved.

> 
>>  			xlog(L_ERROR, "%s requires fsid= for NFS export", path);
>>  		else
>>  			xlog(L_ERROR, "%s does not support NFS export", path);
> 
> 
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diff mbox

Patch

diff --git a/utils/exportfs/exportfs.c b/utils/exportfs/exportfs.c
index c7a79a69b5d6..cac01fc25f9a 100644
--- a/utils/exportfs/exportfs.c
+++ b/utils/exportfs/exportfs.c
@@ -531,7 +531,7 @@  static int can_test(void)
 	return 1;
 }
 
-static int test_export(char *path, int with_fsid)
+static int test_export(char *path, int opts)
 {
 	/* beside max path, buf size should take protocol str into account */
 	char buf[NFS_MAXPATHLEN+1+64] = { 0 };
@@ -545,7 +545,7 @@  static int test_export(char *path, int with_fsid)
 	qword_add(&bp, &len, path);
 	if (len < 1)
 		return 0;
-	snprintf(bp, len, " 3 %d 65534 65534 0\n", with_fsid ? NFSEXP_FSID : 0);
+	snprintf(bp, len, " 3 %d 65534 65534 0\n", opts);
 	fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
 	if (fd < 0)
 		return 0;
@@ -587,12 +587,12 @@  validate_export(nfs_export *exp)
 
 	if ((exp->m_export.e_flags & NFSEXP_FSID) || exp->m_export.e_uuid ||
 	    fs_has_fsid) {
-		if ( !test_export(path, 1)) {
+		if ( !test_export(path, exp->m_export.e_flags)) {
 			xlog(L_ERROR, "%s does not support NFS export", path);
 			return;
 		}
-	} else if ( ! test_export(path, 0)) {
-		if (test_export(path, 1))
+	} else if ( ! test_export(path, exp->m_export.e_flags)) {
+		if (test_export(path, exp->m_export.e_flags & NFSEXP_FSID))
 			xlog(L_ERROR, "%s requires fsid= for NFS export", path);
 		else
 			xlog(L_ERROR, "%s does not support NFS export", path);