* [PATCH 1/3] NFSD: Teach nfsd_mountpoint() auto mounts
2022-12-07 8:43 [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting Richard Weinberger
@ 2022-12-07 8:43 ` Richard Weinberger
2022-12-07 8:43 ` [PATCH 2/3] fs: namei: Allow follow_down() to uncover " Richard Weinberger
` (3 subsequent siblings)
4 siblings, 0 replies; 17+ messages in thread
From: Richard Weinberger @ 2022-12-07 8:43 UTC (permalink / raw)
To: linux-nfs
Cc: linux-kernel, linux-fsdevel, jlayton, chuck.lever, anna,
trond.myklebust, viro, raven, chris.chilvers, david.young,
luis.turcitu, david, benmaynard, Richard Weinberger
Currently nfsd_mountpoint() tests for mount points using d_mountpoint(),
this works only when a mount point is already uncovered.
In our case the mount point is of type auto mount and can be coverted.
i.e. ->d_automount() was not called.
Using d_managed() nfsd_mountpoint() can test whether a mount point is
either already uncovered or can be uncovered later.
Signed-off-by: Richard Weinberger <richard@nod.at>
---
fs/nfsd/vfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index f650afedd67f..157f0df0e93a 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -160,7 +160,7 @@ int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp)
return 1;
if (nfsd4_is_junction(dentry))
return 1;
- if (d_mountpoint(dentry))
+ if (d_managed(dentry))
/*
* Might only be a mountpoint in a different namespace,
* but we need to check.
--
2.26.2
^ permalink raw reply related [flat|nested] 17+ messages in thread
* [PATCH 2/3] fs: namei: Allow follow_down() to uncover auto mounts
2022-12-07 8:43 [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting Richard Weinberger
2022-12-07 8:43 ` [PATCH 1/3] NFSD: Teach nfsd_mountpoint() auto mounts Richard Weinberger
@ 2022-12-07 8:43 ` Richard Weinberger
2022-12-14 15:15 ` [PATCH 2/3] " Chuck Lever III
2023-01-03 16:15 ` Chuck Lever III
2022-12-07 8:43 ` [PATCH 3/3] NFS: nfs_encode_fh: Remove S_AUTOMOUNT check Richard Weinberger
` (2 subsequent siblings)
4 siblings, 2 replies; 17+ messages in thread
From: Richard Weinberger @ 2022-12-07 8:43 UTC (permalink / raw)
To: linux-nfs
Cc: linux-kernel, linux-fsdevel, jlayton, chuck.lever, anna,
trond.myklebust, viro, raven, chris.chilvers, david.young,
luis.turcitu, david, benmaynard, Richard Weinberger
This function is only used by NFSD to cross mount points.
If a mount point is of type auto mount, follow_down() will
not uncover it. Add LOOKUP_AUTOMOUNT to the lookup flags
to have ->d_automount() called when NFSD walks down the
mount tree.
Signed-off-by: Richard Weinberger <richard@nod.at>
---
fs/namei.c | 6 +++---
fs/nfsd/vfs.c | 6 +++++-
include/linux/namei.h | 2 +-
3 files changed, 9 insertions(+), 5 deletions(-)
diff --git a/fs/namei.c b/fs/namei.c
index 578c2110df02..a6bb6863bf0c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1458,11 +1458,11 @@ EXPORT_SYMBOL(follow_down_one);
* point, the filesystem owning that dentry may be queried as to whether the
* caller is permitted to proceed or not.
*/
-int follow_down(struct path *path)
+int follow_down(struct path *path, unsigned int flags)
{
struct vfsmount *mnt = path->mnt;
bool jumped;
- int ret = traverse_mounts(path, &jumped, NULL, 0);
+ int ret = traverse_mounts(path, &jumped, NULL, flags);
if (path->mnt != mnt)
mntput(mnt);
@@ -2864,7 +2864,7 @@ int path_pts(struct path *path)
path->dentry = child;
dput(parent);
- follow_down(path);
+ follow_down(path, 0);
return 0;
}
#endif
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 157f0df0e93a..ced04fc2b947 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -63,9 +63,13 @@ nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
struct dentry *dentry = *dpp;
struct path path = {.mnt = mntget(exp->ex_path.mnt),
.dentry = dget(dentry)};
+ unsigned int follow_flags = 0;
int err = 0;
- err = follow_down(&path);
+ if (exp->ex_flags & NFSEXP_CROSSMOUNT)
+ follow_flags = LOOKUP_AUTOMOUNT;
+
+ err = follow_down(&path, follow_flags);
if (err < 0)
goto out;
if (path.mnt == exp->ex_path.mnt && path.dentry == dentry &&
diff --git a/include/linux/namei.h b/include/linux/namei.h
index 00fee52df842..6f96db73a70a 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -77,7 +77,7 @@ struct dentry *lookup_one_positive_unlocked(struct user_namespace *mnt_userns,
struct dentry *base, int len);
extern int follow_down_one(struct path *);
-extern int follow_down(struct path *);
+extern int follow_down(struct path *, unsigned int flags);
extern int follow_up(struct path *);
extern struct dentry *lock_rename(struct dentry *, struct dentry *);
--
2.26.2
^ permalink raw reply related [flat|nested] 17+ messages in thread
* Re: [PATCH 2/3] namei: Allow follow_down() to uncover auto mounts
2022-12-07 8:43 ` [PATCH 2/3] fs: namei: Allow follow_down() to uncover " Richard Weinberger
@ 2022-12-14 15:15 ` Chuck Lever III
2023-01-03 16:15 ` Chuck Lever III
1 sibling, 0 replies; 17+ messages in thread
From: Chuck Lever III @ 2022-12-14 15:15 UTC (permalink / raw)
To: Al Viro, linux-fsdevel
Cc: Linux NFS Mailing List, LKML, linux-fsdevel, Jeff Layton,
Anna Schumaker, Trond Myklebust, Ian Kent, chris.chilvers,
david.young, luis.turcitu, david, benmaynard, Richard Weinberger
> On Dec 7, 2022, at 3:43 AM, Richard Weinberger <richard@nod.at> wrote:
>
> This function is only used by NFSD to cross mount points.
> If a mount point is of type auto mount, follow_down() will
> not uncover it. Add LOOKUP_AUTOMOUNT to the lookup flags
> to have ->d_automount() called when NFSD walks down the
> mount tree.
>
> Signed-off-by: Richard Weinberger <richard@nod.at>
> ---
> fs/namei.c | 6 +++---
> fs/nfsd/vfs.c | 6 +++++-
> include/linux/namei.h | 2 +-
> 3 files changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/fs/namei.c b/fs/namei.c
> index 578c2110df02..a6bb6863bf0c 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -1458,11 +1458,11 @@ EXPORT_SYMBOL(follow_down_one);
> * point, the filesystem owning that dentry may be queried as to whether the
> * caller is permitted to proceed or not.
> */
> -int follow_down(struct path *path)
> +int follow_down(struct path *path, unsigned int flags)
> {
> struct vfsmount *mnt = path->mnt;
> bool jumped;
> - int ret = traverse_mounts(path, &jumped, NULL, 0);
> + int ret = traverse_mounts(path, &jumped, NULL, flags);
>
> if (path->mnt != mnt)
> mntput(mnt);
> @@ -2864,7 +2864,7 @@ int path_pts(struct path *path)
>
> path->dentry = child;
> dput(parent);
> - follow_down(path);
> + follow_down(path, 0);
> return 0;
> }
> #endif
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index 157f0df0e93a..ced04fc2b947 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -63,9 +63,13 @@ nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
> struct dentry *dentry = *dpp;
> struct path path = {.mnt = mntget(exp->ex_path.mnt),
> .dentry = dget(dentry)};
> + unsigned int follow_flags = 0;
> int err = 0;
>
> - err = follow_down(&path);
> + if (exp->ex_flags & NFSEXP_CROSSMOUNT)
> + follow_flags = LOOKUP_AUTOMOUNT;
> +
> + err = follow_down(&path, follow_flags);
> if (err < 0)
> goto out;
> if (path.mnt == exp->ex_path.mnt && path.dentry == dentry &&
> diff --git a/include/linux/namei.h b/include/linux/namei.h
> index 00fee52df842..6f96db73a70a 100644
> --- a/include/linux/namei.h
> +++ b/include/linux/namei.h
> @@ -77,7 +77,7 @@ struct dentry *lookup_one_positive_unlocked(struct user_namespace *mnt_userns,
> struct dentry *base, int len);
>
> extern int follow_down_one(struct path *);
> -extern int follow_down(struct path *);
> +extern int follow_down(struct path *, unsigned int flags);
> extern int follow_up(struct path *);
>
> extern struct dentry *lock_rename(struct dentry *, struct dentry *);
> --
> 2.26.2
>
I plan to take this through the nfsd tree, thus this one needs
an Ack from the VFS maintainer(s).
--
Chuck Lever
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 2/3] namei: Allow follow_down() to uncover auto mounts
2022-12-07 8:43 ` [PATCH 2/3] fs: namei: Allow follow_down() to uncover " Richard Weinberger
2022-12-14 15:15 ` [PATCH 2/3] " Chuck Lever III
@ 2023-01-03 16:15 ` Chuck Lever III
2023-01-29 15:42 ` Richard Weinberger
1 sibling, 1 reply; 17+ messages in thread
From: Chuck Lever III @ 2023-01-03 16:15 UTC (permalink / raw)
To: Al Viro
Cc: Linux NFS Mailing List, Richard Weinberger, LKML, linux-fsdevel,
Jeff Layton, Anna Schumaker, Trond Myklebust, Ian Kent,
chris.chilvers, david.young, luis.turcitu, david, benmaynard
> On Dec 7, 2022, at 3:43 AM, Richard Weinberger <richard@nod.at> wrote:
>
> This function is only used by NFSD to cross mount points.
> If a mount point is of type auto mount, follow_down() will
> not uncover it. Add LOOKUP_AUTOMOUNT to the lookup flags
> to have ->d_automount() called when NFSD walks down the
> mount tree.
>
> Signed-off-by: Richard Weinberger <richard@nod.at>
Hello Al, you are top of the maintainers listed for fs/namei.c.
I'd like to take this series for v6.3 via the nfsd tree. Can
I get your Acked-by: for this one?
> ---
> fs/namei.c | 6 +++---
> fs/nfsd/vfs.c | 6 +++++-
> include/linux/namei.h | 2 +-
> 3 files changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/fs/namei.c b/fs/namei.c
> index 578c2110df02..a6bb6863bf0c 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -1458,11 +1458,11 @@ EXPORT_SYMBOL(follow_down_one);
> * point, the filesystem owning that dentry may be queried as to whether the
> * caller is permitted to proceed or not.
> */
> -int follow_down(struct path *path)
> +int follow_down(struct path *path, unsigned int flags)
> {
> struct vfsmount *mnt = path->mnt;
> bool jumped;
> - int ret = traverse_mounts(path, &jumped, NULL, 0);
> + int ret = traverse_mounts(path, &jumped, NULL, flags);
>
> if (path->mnt != mnt)
> mntput(mnt);
> @@ -2864,7 +2864,7 @@ int path_pts(struct path *path)
>
> path->dentry = child;
> dput(parent);
> - follow_down(path);
> + follow_down(path, 0);
> return 0;
> }
> #endif
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index 157f0df0e93a..ced04fc2b947 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -63,9 +63,13 @@ nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
> struct dentry *dentry = *dpp;
> struct path path = {.mnt = mntget(exp->ex_path.mnt),
> .dentry = dget(dentry)};
> + unsigned int follow_flags = 0;
> int err = 0;
>
> - err = follow_down(&path);
> + if (exp->ex_flags & NFSEXP_CROSSMOUNT)
> + follow_flags = LOOKUP_AUTOMOUNT;
> +
> + err = follow_down(&path, follow_flags);
> if (err < 0)
> goto out;
> if (path.mnt == exp->ex_path.mnt && path.dentry == dentry &&
> diff --git a/include/linux/namei.h b/include/linux/namei.h
> index 00fee52df842..6f96db73a70a 100644
> --- a/include/linux/namei.h
> +++ b/include/linux/namei.h
> @@ -77,7 +77,7 @@ struct dentry *lookup_one_positive_unlocked(struct user_namespace *mnt_userns,
> struct dentry *base, int len);
>
> extern int follow_down_one(struct path *);
> -extern int follow_down(struct path *);
> +extern int follow_down(struct path *, unsigned int flags);
> extern int follow_up(struct path *);
>
> extern struct dentry *lock_rename(struct dentry *, struct dentry *);
> --
> 2.26.2
>
--
Chuck Lever
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 2/3] namei: Allow follow_down() to uncover auto mounts
2023-01-03 16:15 ` Chuck Lever III
@ 2023-01-29 15:42 ` Richard Weinberger
2023-01-30 2:15 ` Al Viro
0 siblings, 1 reply; 17+ messages in thread
From: Richard Weinberger @ 2023-01-29 15:42 UTC (permalink / raw)
To: chuck lever, Al Viro
Cc: linux-nfs, linux-kernel, linux-fsdevel, Jeff Layton, anna,
trond myklebust, raven, chris chilvers, david young,
luis turcitu, david, benmaynard
----- Ursprüngliche Mail -----
> Von: "chuck lever" <chuck.lever@oracle.com>
>> On Dec 7, 2022, at 3:43 AM, Richard Weinberger <richard@nod.at> wrote:
>>
>> This function is only used by NFSD to cross mount points.
>> If a mount point is of type auto mount, follow_down() will
>> not uncover it. Add LOOKUP_AUTOMOUNT to the lookup flags
>> to have ->d_automount() called when NFSD walks down the
>> mount tree.
>>
>> Signed-off-by: Richard Weinberger <richard@nod.at>
>
> Hello Al, you are top of the maintainers listed for fs/namei.c.
> I'd like to take this series for v6.3 via the nfsd tree. Can
> I get your Acked-by: for this one?
ping?
Thanks,
//richard
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 2/3] namei: Allow follow_down() to uncover auto mounts
2023-01-29 15:42 ` Richard Weinberger
@ 2023-01-30 2:15 ` Al Viro
0 siblings, 0 replies; 17+ messages in thread
From: Al Viro @ 2023-01-30 2:15 UTC (permalink / raw)
To: Richard Weinberger
Cc: chuck lever, linux-nfs, linux-kernel, linux-fsdevel, Jeff Layton,
anna, trond myklebust, raven, chris chilvers, david young,
luis turcitu, david, benmaynard
On Sun, Jan 29, 2023 at 04:42:39PM +0100, Richard Weinberger wrote:
> ----- Ursprüngliche Mail -----
> > Von: "chuck lever" <chuck.lever@oracle.com>
> >> On Dec 7, 2022, at 3:43 AM, Richard Weinberger <richard@nod.at> wrote:
> >>
> >> This function is only used by NFSD to cross mount points.
> >> If a mount point is of type auto mount, follow_down() will
> >> not uncover it. Add LOOKUP_AUTOMOUNT to the lookup flags
> >> to have ->d_automount() called when NFSD walks down the
> >> mount tree.
> >>
> >> Signed-off-by: Richard Weinberger <richard@nod.at>
> >
> > Hello Al, you are top of the maintainers listed for fs/namei.c.
> > I'd like to take this series for v6.3 via the nfsd tree. Can
> > I get your Acked-by: for this one?
>
> ping?
modulo clumsy wording ("mount point is of type auto mount")
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Commit message sounds as if it refered to autofs, rather than NFS referrals
et.al. and AFAICS those are the cases it's really about...
^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 3/3] NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
2022-12-07 8:43 [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting Richard Weinberger
2022-12-07 8:43 ` [PATCH 1/3] NFSD: Teach nfsd_mountpoint() auto mounts Richard Weinberger
2022-12-07 8:43 ` [PATCH 2/3] fs: namei: Allow follow_down() to uncover " Richard Weinberger
@ 2022-12-07 8:43 ` Richard Weinberger
2022-12-14 15:09 ` Chuck Lever III
2022-12-10 16:09 ` [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting Chuck Lever III
2022-12-12 17:06 ` Jeff Layton
4 siblings, 1 reply; 17+ messages in thread
From: Richard Weinberger @ 2022-12-07 8:43 UTC (permalink / raw)
To: linux-nfs
Cc: linux-kernel, linux-fsdevel, jlayton, chuck.lever, anna,
trond.myklebust, viro, raven, chris.chilvers, david.young,
luis.turcitu, david, benmaynard, Richard Weinberger
Now with NFSD being able to cross into auto mounts,
the check can be removed.
Signed-off-by: Richard Weinberger <richard@nod.at>
---
fs/nfs/export.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/nfs/export.c b/fs/nfs/export.c
index 01596f2d0a1e..0a5ee1754d50 100644
--- a/fs/nfs/export.c
+++ b/fs/nfs/export.c
@@ -42,7 +42,7 @@ nfs_encode_fh(struct inode *inode, __u32 *p, int *max_len, struct inode *parent)
dprintk("%s: max fh len %d inode %p parent %p",
__func__, *max_len, inode, parent);
- if (*max_len < len || IS_AUTOMOUNT(inode)) {
+ if (*max_len < len) {
dprintk("%s: fh len %d too small, required %d\n",
__func__, *max_len, len);
*max_len = len;
--
2.26.2
^ permalink raw reply related [flat|nested] 17+ messages in thread
* Re: [PATCH 3/3] NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
2022-12-07 8:43 ` [PATCH 3/3] NFS: nfs_encode_fh: Remove S_AUTOMOUNT check Richard Weinberger
@ 2022-12-14 15:09 ` Chuck Lever III
2022-12-14 16:37 ` Anna Schumaker
0 siblings, 1 reply; 17+ messages in thread
From: Chuck Lever III @ 2022-12-14 15:09 UTC (permalink / raw)
To: Anna Schumaker, Trond Myklebust
Cc: Linux NFS Mailing List, LKML, linux-fsdevel, Jeff Layton,
Al Viro, Ian Kent, chris.chilvers, david.young, luis.turcitu,
david, benmaynard, Richard Weinberger
> On Dec 7, 2022, at 3:43 AM, Richard Weinberger <richard@nod.at> wrote:
>
> Now with NFSD being able to cross into auto mounts,
> the check can be removed.
>
> Signed-off-by: Richard Weinberger <richard@nod.at>
> ---
> fs/nfs/export.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/nfs/export.c b/fs/nfs/export.c
> index 01596f2d0a1e..0a5ee1754d50 100644
> --- a/fs/nfs/export.c
> +++ b/fs/nfs/export.c
> @@ -42,7 +42,7 @@ nfs_encode_fh(struct inode *inode, __u32 *p, int *max_len, struct inode *parent)
> dprintk("%s: max fh len %d inode %p parent %p",
> __func__, *max_len, inode, parent);
>
> - if (*max_len < len || IS_AUTOMOUNT(inode)) {
> + if (*max_len < len) {
> dprintk("%s: fh len %d too small, required %d\n",
> __func__, *max_len, len);
> *max_len = len;
> --
> 2.26.2
>
I plan to take this through the nfsd tree, thus this one needs
an Ack from the NFS client maintainers.
--
Chuck Lever
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 3/3] NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
2022-12-14 15:09 ` Chuck Lever III
@ 2022-12-14 16:37 ` Anna Schumaker
2022-12-14 16:39 ` Chuck Lever III
0 siblings, 1 reply; 17+ messages in thread
From: Anna Schumaker @ 2022-12-14 16:37 UTC (permalink / raw)
To: Chuck Lever III
Cc: Trond Myklebust, Linux NFS Mailing List, LKML, linux-fsdevel,
Jeff Layton, Al Viro, Ian Kent, chris.chilvers, david.young,
luis.turcitu, david, benmaynard, Richard Weinberger
On Wed, Dec 14, 2022 at 10:09 AM Chuck Lever III <chuck.lever@oracle.com> wrote:
>
>
>
> > On Dec 7, 2022, at 3:43 AM, Richard Weinberger <richard@nod.at> wrote:
> >
> > Now with NFSD being able to cross into auto mounts,
> > the check can be removed.
> >
> > Signed-off-by: Richard Weinberger <richard@nod.at>
> > ---
> > fs/nfs/export.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/fs/nfs/export.c b/fs/nfs/export.c
> > index 01596f2d0a1e..0a5ee1754d50 100644
> > --- a/fs/nfs/export.c
> > +++ b/fs/nfs/export.c
> > @@ -42,7 +42,7 @@ nfs_encode_fh(struct inode *inode, __u32 *p, int *max_len, struct inode *parent)
> > dprintk("%s: max fh len %d inode %p parent %p",
> > __func__, *max_len, inode, parent);
> >
> > - if (*max_len < len || IS_AUTOMOUNT(inode)) {
> > + if (*max_len < len) {
> > dprintk("%s: fh len %d too small, required %d\n",
> > __func__, *max_len, len);
> > *max_len = len;
> > --
> > 2.26.2
> >
>
> I plan to take this through the nfsd tree, thus this one needs
> an Ack from the NFS client maintainers.
Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
>
> --
> Chuck Lever
>
>
>
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 3/3] NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
2022-12-14 16:37 ` Anna Schumaker
@ 2022-12-14 16:39 ` Chuck Lever III
0 siblings, 0 replies; 17+ messages in thread
From: Chuck Lever III @ 2022-12-14 16:39 UTC (permalink / raw)
To: Anna Schumaker
Cc: Trond Myklebust, Linux NFS Mailing List, LKML, linux-fsdevel,
Jeff Layton, Al Viro, Ian Kent, chris.chilvers, david.young,
luis.turcitu, david, benmaynard, Richard Weinberger
> On Dec 14, 2022, at 11:37 AM, Anna Schumaker <anna@kernel.org> wrote:
>
> On Wed, Dec 14, 2022 at 10:09 AM Chuck Lever III <chuck.lever@oracle.com> wrote:
>>
>>
>>
>>> On Dec 7, 2022, at 3:43 AM, Richard Weinberger <richard@nod.at> wrote:
>>>
>>> Now with NFSD being able to cross into auto mounts,
>>> the check can be removed.
>>>
>>> Signed-off-by: Richard Weinberger <richard@nod.at>
>>> ---
>>> fs/nfs/export.c | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/fs/nfs/export.c b/fs/nfs/export.c
>>> index 01596f2d0a1e..0a5ee1754d50 100644
>>> --- a/fs/nfs/export.c
>>> +++ b/fs/nfs/export.c
>>> @@ -42,7 +42,7 @@ nfs_encode_fh(struct inode *inode, __u32 *p, int *max_len, struct inode *parent)
>>> dprintk("%s: max fh len %d inode %p parent %p",
>>> __func__, *max_len, inode, parent);
>>>
>>> - if (*max_len < len || IS_AUTOMOUNT(inode)) {
>>> + if (*max_len < len) {
>>> dprintk("%s: fh len %d too small, required %d\n",
>>> __func__, *max_len, len);
>>> *max_len = len;
>>> --
>>> 2.26.2
>>>
>>
>> I plan to take this through the nfsd tree, thus this one needs
>> an Ack from the NFS client maintainers.
>
> Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Thanks!
--
Chuck Lever
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting
2022-12-07 8:43 [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting Richard Weinberger
` (2 preceding siblings ...)
2022-12-07 8:43 ` [PATCH 3/3] NFS: nfs_encode_fh: Remove S_AUTOMOUNT check Richard Weinberger
@ 2022-12-10 16:09 ` Chuck Lever III
2022-12-10 21:52 ` Richard Weinberger
2022-12-12 17:06 ` Jeff Layton
4 siblings, 1 reply; 17+ messages in thread
From: Chuck Lever III @ 2022-12-10 16:09 UTC (permalink / raw)
To: Richard Weinberger
Cc: Linux NFS Mailing List, LKML, linux-fsdevel, Jeff Layton,
Anna Schumaker, Trond Myklebust, Al Viro, Ian Kent,
chris.chilvers, david.young, luis.turcitu, david, benmaynard
> On Dec 7, 2022, at 3:43 AM, Richard Weinberger <richard@nod.at> wrote:
>
> Currently when re-exporting a NFS share the NFS cross mount feature does
> not work [0].
> This patch series outlines an approach to address the problem.
>
> Crossing mounts does not work for two reasons:
>
> 1. As soon the NFS client (on the re-exporting server) sees a different
> filesystem id, it installs an automount. That way the other filesystem
> will be mounted automatically when someone enters the directory.
> But the cross mount logic of KNFS does not know about automount.
> This patch series addresses the problem and teach both KNFSD
> and the exportfs logic of NFS to deal with automount.
>
> 2. When KNFSD detects crossing of a mount point, it asks rpc.mountd to install
> a new export for the target mount point. Beside of authentication rpc.mountd
> also has to find a filesystem id for the new export. Is the to be exported
> filesystem a NFS share, rpc.mountd cannot derive a filesystem id from it and
> refuses to export. In the logs you'll see errors such as:
>
> mountd: Cannot export /srv/nfs/vol0, possibly unsupported filesystem or fsid= required
>
> To deal with that I've changed rpc.mountd to use generate and store fsids [1].
> Since the kernel side of my changes did change for a long time I decided to
> try upstreaming it first.
> A 3rd iteration of my rpc.mountd will happen soon.
>
> [0] https://marc.info/?l=linux-nfs&m=161653016627277&w=2
> [1] https://lore.kernel.org/linux-nfs/20220217131531.2890-1-richard@nod.at/
>
> Changes since v1:
> https://lore.kernel.org/linux-nfs/20221117191151.14262-1-richard@nod.at/
>
> - Use LOOKUP_AUTOMOUNT only when NFSEXP_CROSSMOUNT is set (Jeff Layton)
>
> Richard Weinberger (3):
> NFSD: Teach nfsd_mountpoint() auto mounts
> fs: namei: Allow follow_down() to uncover auto mounts
> NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
>
> fs/namei.c | 6 +++---
> fs/nfs/export.c | 2 +-
> fs/nfsd/vfs.c | 8 ++++++--
> include/linux/namei.h | 2 +-
> 4 files changed, 11 insertions(+), 7 deletions(-)
>
> --
> 2.26.2
>
This series is a bit late for inclusion in v6.2. The next opportunity
will be v6.3 in a couple of months. I prefer to have a "final" version
of patches by -rc5.
I'm waiting for review comments on v2 of this series.
--
Chuck Lever
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting
2022-12-10 16:09 ` [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting Chuck Lever III
@ 2022-12-10 21:52 ` Richard Weinberger
2022-12-10 21:53 ` Chuck Lever III
0 siblings, 1 reply; 17+ messages in thread
From: Richard Weinberger @ 2022-12-10 21:52 UTC (permalink / raw)
To: chuck lever
Cc: linux-nfs, linux-kernel, linux-fsdevel, Jeff Layton, anna,
trond myklebust, Al Viro, raven, chris chilvers, david young,
luis turcitu, david, benmaynard
----- Ursprüngliche Mail -----
> Von: "chuck lever" <chuck.lever@oracle.com>
>> Richard Weinberger (3):
>> NFSD: Teach nfsd_mountpoint() auto mounts
>> fs: namei: Allow follow_down() to uncover auto mounts
>> NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
>>
>> fs/namei.c | 6 +++---
>> fs/nfs/export.c | 2 +-
>> fs/nfsd/vfs.c | 8 ++++++--
>> include/linux/namei.h | 2 +-
>> 4 files changed, 11 insertions(+), 7 deletions(-)
>>
>> --
>> 2.26.2
>>
>
> This series is a bit late for inclusion in v6.2. The next opportunity
> will be v6.3 in a couple of months. I prefer to have a "final" version
> of patches by -rc5.
>
> I'm waiting for review comments on v2 of this series.
Ok! Do you want me to resend the series in any case by v6.2-rc5 or only
if new comments arise?
Thanks,
//richard
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting
2022-12-10 21:52 ` Richard Weinberger
@ 2022-12-10 21:53 ` Chuck Lever III
0 siblings, 0 replies; 17+ messages in thread
From: Chuck Lever III @ 2022-12-10 21:53 UTC (permalink / raw)
To: Richard Weinberger
Cc: Linux NFS Mailing List, linux-kernel, linux-fsdevel, Jeff Layton,
anna, trond myklebust, Al Viro, raven, chris chilvers,
david young, luis turcitu, david, benmaynard
> On Dec 10, 2022, at 4:52 PM, Richard Weinberger <richard@nod.at> wrote:
>
> ----- Ursprüngliche Mail -----
>> Von: "chuck lever" <chuck.lever@oracle.com>
>>> Richard Weinberger (3):
>>> NFSD: Teach nfsd_mountpoint() auto mounts
>>> fs: namei: Allow follow_down() to uncover auto mounts
>>> NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
>>>
>>> fs/namei.c | 6 +++---
>>> fs/nfs/export.c | 2 +-
>>> fs/nfsd/vfs.c | 8 ++++++--
>>> include/linux/namei.h | 2 +-
>>> 4 files changed, 11 insertions(+), 7 deletions(-)
>>>
>>> --
>>> 2.26.2
>>>
>>
>> This series is a bit late for inclusion in v6.2. The next opportunity
>> will be v6.3 in a couple of months. I prefer to have a "final" version
>> of patches by -rc5.
>>
>> I'm waiting for review comments on v2 of this series.
>
> Ok! Do you want me to resend the series in any case by v6.2-rc5 or only
> if new comments arise?
If v2 garners no new comments, then send a reminder with a URL to this
thread on lore.kernel.org. I will pull the series from there.
--
Chuck Lever
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting
2022-12-07 8:43 [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting Richard Weinberger
` (3 preceding siblings ...)
2022-12-10 16:09 ` [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting Chuck Lever III
@ 2022-12-12 17:06 ` Jeff Layton
2022-12-13 9:09 ` Ian Kent
4 siblings, 1 reply; 17+ messages in thread
From: Jeff Layton @ 2022-12-12 17:06 UTC (permalink / raw)
To: Richard Weinberger, linux-nfs
Cc: linux-kernel, linux-fsdevel, chuck.lever, anna, trond.myklebust,
viro, raven, chris.chilvers, david.young, luis.turcitu, david,
benmaynard
On Wed, 2022-12-07 at 09:43 +0100, Richard Weinberger wrote:
> Currently when re-exporting a NFS share the NFS cross mount feature does
> not work [0].
> This patch series outlines an approach to address the problem.
>
> Crossing mounts does not work for two reasons:
>
> 1. As soon the NFS client (on the re-exporting server) sees a different
> filesystem id, it installs an automount. That way the other filesystem
> will be mounted automatically when someone enters the directory.
> But the cross mount logic of KNFS does not know about automount.
> This patch series addresses the problem and teach both KNFSD
> and the exportfs logic of NFS to deal with automount.
>
> 2. When KNFSD detects crossing of a mount point, it asks rpc.mountd to install
> a new export for the target mount point. Beside of authentication rpc.mountd
> also has to find a filesystem id for the new export. Is the to be exported
> filesystem a NFS share, rpc.mountd cannot derive a filesystem id from it and
> refuses to export. In the logs you'll see errors such as:
>
> mountd: Cannot export /srv/nfs/vol0, possibly unsupported filesystem or fsid= required
>
> To deal with that I've changed rpc.mountd to use generate and store fsids [1].
> Since the kernel side of my changes did change for a long time I decided to
> try upstreaming it first.
> A 3rd iteration of my rpc.mountd will happen soon.
>
> [0] https://marc.info/?l=linux-nfs&m=161653016627277&w=2
> [1] https://lore.kernel.org/linux-nfs/20220217131531.2890-1-richard@nod.at/
>
> Changes since v1:
> https://lore.kernel.org/linux-nfs/20221117191151.14262-1-richard@nod.at/
>
> - Use LOOKUP_AUTOMOUNT only when NFSEXP_CROSSMOUNT is set (Jeff Layton)
>
> Richard Weinberger (3):
> NFSD: Teach nfsd_mountpoint() auto mounts
> fs: namei: Allow follow_down() to uncover auto mounts
> NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
>
> fs/namei.c | 6 +++---
> fs/nfs/export.c | 2 +-
> fs/nfsd/vfs.c | 8 ++++++--
> include/linux/namei.h | 2 +-
> 4 files changed, 11 insertions(+), 7 deletions(-)
>
This set looks reasonable to me.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCH 0/3 v2] NFS: NFSD: Allow crossing mounts when re-exporting
2022-12-12 17:06 ` Jeff Layton
@ 2022-12-13 9:09 ` Ian Kent
0 siblings, 0 replies; 17+ messages in thread
From: Ian Kent @ 2022-12-13 9:09 UTC (permalink / raw)
To: Jeff Layton, Richard Weinberger, linux-nfs
Cc: linux-kernel, linux-fsdevel, chuck.lever, anna, trond.myklebust,
viro, chris.chilvers, david.young, luis.turcitu, david,
benmaynard
On 13/12/22 01:06, Jeff Layton wrote:
> On Wed, 2022-12-07 at 09:43 +0100, Richard Weinberger wrote:
>> Currently when re-exporting a NFS share the NFS cross mount feature does
>> not work [0].
>> This patch series outlines an approach to address the problem.
>>
>> Crossing mounts does not work for two reasons:
>>
>> 1. As soon the NFS client (on the re-exporting server) sees a different
>> filesystem id, it installs an automount. That way the other filesystem
>> will be mounted automatically when someone enters the directory.
>> But the cross mount logic of KNFS does not know about automount.
>> This patch series addresses the problem and teach both KNFSD
>> and the exportfs logic of NFS to deal with automount.
>>
>> 2. When KNFSD detects crossing of a mount point, it asks rpc.mountd to install
>> a new export for the target mount point. Beside of authentication rpc.mountd
>> also has to find a filesystem id for the new export. Is the to be exported
>> filesystem a NFS share, rpc.mountd cannot derive a filesystem id from it and
>> refuses to export. In the logs you'll see errors such as:
>>
>> mountd: Cannot export /srv/nfs/vol0, possibly unsupported filesystem or fsid= required
>>
>> To deal with that I've changed rpc.mountd to use generate and store fsids [1].
>> Since the kernel side of my changes did change for a long time I decided to
>> try upstreaming it first.
>> A 3rd iteration of my rpc.mountd will happen soon.
>>
>> [0] https://marc.info/?l=linux-nfs&m=161653016627277&w=2
>> [1] https://lore.kernel.org/linux-nfs/20220217131531.2890-1-richard@nod.at/
>>
>> Changes since v1:
>> https://lore.kernel.org/linux-nfs/20221117191151.14262-1-richard@nod.at/
>>
>> - Use LOOKUP_AUTOMOUNT only when NFSEXP_CROSSMOUNT is set (Jeff Layton)
>>
>> Richard Weinberger (3):
>> NFSD: Teach nfsd_mountpoint() auto mounts
>> fs: namei: Allow follow_down() to uncover auto mounts
>> NFS: nfs_encode_fh: Remove S_AUTOMOUNT check
>>
>> fs/namei.c | 6 +++---
>> fs/nfs/export.c | 2 +-
>> fs/nfsd/vfs.c | 8 ++++++--
>> include/linux/namei.h | 2 +-
>> 4 files changed, 11 insertions(+), 7 deletions(-)
>>
> This set looks reasonable to me.
>
> Reviewed-by: Jeff Layton <jlayton@kernel.org>
Right, looks ok to me too, at least from the POV of that follow_down()
change.
Reviewed-by: Ian Kent <raven@themaw.net>
Ian
^ permalink raw reply [flat|nested] 17+ messages in thread