This patch splits out the NFS v4 specific functionality of
nfs4_get_root() into its own rpc_op called by the generic client, and
leaves nfs4_proc_get_rootfh() as its own stand alone function.  This
also allows me to change nfs4_remote_mount(), nfs4_xdev_mount() and
nfs4_remote_referral_mount() to use the generic client's nfs_get_root()
function.  Later patches in this series will collapse these functions
into one common function, so using the same get_root() function
everywhere simplifies future changes.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The authflavor is set in an nfs_clone_mount structure and passed to the
xdev_mount() functions where it was promptly ignored.  Instead, use it
to initialize an rpc_clnt for the cloned server.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When hostname contains colon (e.g. when it is an IPv6 address) it needs
to be enclosed in brackets to make parsing of NFS device string possible.
Fix nfs_do_root_mount() to enclose hostname properly when needed. NFS code
actually does not need this as it does not parse the string passed by
nfs_do_root_mount() but the device string is exposed to userspace in
/proc/mounts.

CC: Josh Boyer <jwboyer@redhat.com>
CC: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

NFS bdi flush thread in ps output is printed like "flush-<major number
in decimal>:<minor number in decimal>"
For example:
$ ps aux | grep flush
 2079 root         0 SW   [flush-0:18]
                                 ^^^^

nfs_bdi_register()
==> bdi_register_dev()
==> bdi_register(bdi, NULL, "%u:%u", MAJOR(dev), MINOR(dev));
                             ^^^^^

However, NFS sb->s_id store major:minor number in hex:

nfs_initialise_sb()
==>         snprintf(sb->s_id, sizeof(sb->s_id),
                 "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
                  ^^^^^

If we enable nfs debug prints using command:
$ rpcdebug -m nfs -s all

write to a file:
$ dd if=/dev/zero of=<NFS Mount>/testfile.txt bs=32768 count=1

Without Patch:
[ 2431.032000] NFS:     0 initiated write call (req 0:12/40, 32768 bytes
@ offset 0)                                         ^^^^

With Patch:
[ 2431.032000] NFS:     0 initiated write call (req 0:18/40, 32768 bytes
@ offset 0)                                         ^^^^

We should store NFS "s->s_id" in decimal to avoid confusion between NFS
flush thread name(in ps output) and NFS debug prints.
Signed-off-by: NVivek Trivedi <vtrivedi018@gmail.com>
Signed-off-by: NNamjae Jeon <linkinjeon@gmail.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The attempt to display the implementation ID needs to be conditional on
whether or not CONFIG_NFS_V4_1 is defined
Reported-by: NBryan Schumaker <Bryan.Schumaker@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For NFSv4 mounts, the clientaddr= mount option has always been
required.  Now we have rpc_localaddr() in the kernel, which was
modeled after the same logic in the mount.nfs command that constructs
the clientaddr= mount option.  If user space doesn't provide a
clientaddr= mount option, the kernel can now construct its own.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

A migration event will replace the rpc_xprt used by an rpc_clnt.  To
ensure this can be done safely, all references to cl_xprt must now use
a form of rcu_dereference().

Special care is taken with rpc_peeraddr2str(), which returns a pointer
to memory whose lifetime is the same as the rpc_xprt.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
[ cel: fix lockdep splats and layering violations ]
[ cel: forward ported to 3.4 ]
[ cel: remove rpc_max_reqs(), add rpc_net_ns() ]
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The 'minorversion' mount option is now deprecated, so we need to display
the minor version number in the 'vers=' format.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Allow the user to mount an NFSv4.0 or NFSv4.1 partition using a
standard syntax of '-overs=4.0', or '-overs=4.1' rather than the
more cumbersome '-overs=4,minorversion=1'.

See also the earlier patch by Dros Adamson, which added the
Linux-specific syntax '-ov4.0', '-ov4.1'.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Shows the implementation ids in /proc/self/mountstats.  This doesn't break
the nfs-utils mountstats tool.
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Currently, the nfs_parsed_mount_data->net field is initialised in
the nfs_parse_mount_options() function, which means that it only
gets set if we're using text based mounts. The legacy binary
mount interface is therefore broken.

Fix is to initialise the ->net field in nfs_alloc_parsed_mount_data.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>

Don't allow invalid 'vers' and 'minorversion' combinations in mount options,
such as "vers=3,minorversion=1".
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NStanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

"data" is never NULL here.
Reported-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Parametrize rpc_pton() by network context and thus force it's callers to pass
in network context instead of using hard-coded "init_net".
Signed-off-by: NStanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch replaces static "init_net" with nfs_client->net pointer in RPC
client creation calls.
Signed-off-by: NStanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch adds new net variable to nfs_client structure. This variable is set
on NFS client creation and cheched during matching NFS client search.
Initially current->nsproxy->net_ns is used as network namespace owner for new
NFS client to create. This network namespace pointer is set during mount
options parsing and thus can be passed from user-spave utils in future if will
be necessary.
Signed-off-by: NStanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Setting the security context of a NFSv4 mount via the context= mount
option is currently broken. The NFSv4 codepath allocates a parsed
options struct, and then parses the mount options to fill it. It
eventually calls nfs4_remote_mount which calls security_init_mnt_opts.
That clobbers the lsm_opts struct that was populated earlier. This bug
also looks like it causes a small memory leak on each v4 mount where
context= is used.

Fix this by moving the initialization of the lsm_opts into
nfs_alloc_parsed_mount_data. Also, add a destructor for
nfs_parsed_mount_data to make it easier to free all of the allocations
hanging off of it, and to ensure that the security_free_mnt_opts is
called whenever security_init_mnt_opts is.

I believe this regression was introduced quite some time ago, probably
by commit c02d7adf.

Cc: stable@vger.kernel.org
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

... rather than duplicating that in callers
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

it's not needed anymore; we used to, back when we had to do
mount_subtree() by hand, complete with put_mnt_ns() in it.
No more...  Apparmor didn't need it since the __d_path() fix.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

takes vfsmount and relative path, does lookup within that vfsmount
(possibly triggering automounts) and returns the result as root
of subtree suitable for return by ->mount() (i.e. a reference to
dentry and an active reference to its superblock grabbed, superblock
locked exclusive).

btrfs and nfs switched to it instead of open-coding the sucker.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Life is much saner if create_mnt_ns(mnt) drops mnt in case of error...
Switch it to such calling conventions, switch callers, fix double mntput() in
fs/nfs/super.c one.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

commit ae50c0b5 "pnfs: client stats" added additional information to
the output of /proc/self/mountstats. The new functions introduced are
only used in this file and should be marked static.

If CONFIG_NFS_V4_1 is not defined, empty stub functions are used.  If
CONFIG_NFS_V4 is not defined these stub functions are not used at all.
Adding static for the functions results in compile warnings:

fs/nfs/super.c:743: warning: 'show_sessions' defined but not used
fs/nfs/super.c:756: warning: 'show_pnfs' defined but not used

Fix this by adding a #ifdef CONFIG_NFS_V4 guard around the two
show_ functions.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The concensus seems to be that system calls such as stat() etc should
not trigger an automount.  Neither should the l* versions.

This patch therefore adds a LOOKUP_AUTOMOUNT flag to tag those lookups
that _should_ trigger an automount on the last path element.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
[ Edited to leave out the cases that are already covered by LOOKUP_OPEN,
  LOOKUP_DIRECTORY and LOOKUP_CREATE - all of which also fundamentally
  force automounting for their own reasons   - Linus ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Do not allow multiple mounts on same mountpoint when using -o noac

When you normally attempt to mount a share twice on the same mountpoint,
a check in do_add_mount causes it to return an error

# mount localhost:/nfsv3 /mnt
# mount localhost:/nfsv3 /mnt
mount.nfs: /mnt is already mounted or busy

However when using the option 'noac', the user is able to mount the same
share on the same mountpoint multiple times. This happens because a
share mounted with the noac option is automatically assigned the 'sync'
flag MS_SYNCHRONOUS in nfs_initialise_sb(). This flag is set after the
check for already existing superblocks is done in sget(). The check for
the mount flags in nfs_compare_mount_options() does not take into
account the 'sync' flag applied later on in the code path. This means
that when using 'noac', a new superblock structure is assigned for every
new mount of the same share and multiple shares on the same mountpoint
are allowed.

ie.
# mount -onoac localhost:/nfsv3 /mnt
can be run multiple times.

The patch checks for noac and assigns the sync flag before sget() is
called to obtain an already existing superblock structure.
Signed-off-by: NSachin Prabhu <sprabhu@redhat.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

A pNFS client auto-negotiates a lot of features (minorversion level,
pNFS layout type, etc.).  This is convenient, but makes certain kinds of
failures hard for a user to detect.

For example, if the client falls back on 4.0, or falls back to MDS IO
because the user didn't connect to the right iscsi disks before
mounting, the only symptoms may be reduced performance, which may not be
noticed till long after the actual failure, and may be difficult for a
user to diagnose.

However, such "failures" may also be perfectly normal in some cases, so
we don't want to spam the system logs with them.

One approach would be to put some more information into
/proc/self/mountstats.
Signed-off-by: NJ. Bruce Fields <bfields@fieldses.org>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[pnfs: add commit client stats]
[fixup data types for "ret" variables in pnfs_try_to* inline funcs.]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[fix definition of show_pnfs for !CONFIG_PNFS]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfs41: Fix show_sessions in the not CONFIG_NFS_V4_1 case]
    There is a build error when CONFIG_NFS_V4 is set but
    CONFIG_NFS_V4_1 is *not* set. show_sessions() prototype
    was unbalanced between the two cases.
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
[pnfs: super.c remove CONFIG_PNFS]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>

On a remount, the VFS layer will clear the MS_SYNCHRONOUS bit on the
assumption that the flags on the mount syscall will have it set if the
remounted fs is supposed to keep it.

In the case of "noac" though, MS_SYNCHRONOUS is implied. A remount of
such a mount will lose the MS_SYNCHRONOUS flag since "sync" isn't part
of the mount options.
Reported-by: NMax Matveev <makc@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Cc: stable@kernel.org
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We were always attempting sec flavor negotiation, even if the user
told us a specific sec flavor to use.  If that sec flavor fails,
we should return an error rather than continuing with sec flavor
negotiation.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In fs/nfs/super.c::nfs_fs_mount() we test for a NULL 'data':

...
 		if (data == NULL || mntfh == NULL)
 			goto out_free_fh;
...

and then further down in the function we test 'data' again:

...
 			nfs_fscache_get_super_cookie(
 				s, data ? data->fscache_uniq : NULL, NULL);
...

this second check is just dead code since there is no way 'data' could
possibly be NULL here.
We also rely on a non-NULL 'data' in more than one location between these
two tests, further proving the point that the second test is bogus.

This patch removes the dead code.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The last remaining instances of ->get_sb() can be converted ->mount()
now - nothing in them uses new vfsmount anymore.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

now we can do that - nobody cares about its value anymore.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

a) ->show_devname(m, mnt) - what to put into devname columns in mounts,
mountinfo and mountstats
b) ->show_path(m, mnt) - what to put into relative path column in mountinfo

Leaving those NULL gives old behaviour.  NFS switched to using those.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>