Ian Kent reports:

"I've noticed a couple of other regressions with the options vers
and proto option of mount.nfs(8).

The commands:

mount -t nfs -o vers=<invalid version> <server>:/<path> /<mountpoint>
mount -t nfs -o proto=<invalid proto> <server>:/<path> /<mountpoint>

both immediately fail.

But if the "-s" option is also used they both succeed with the
mount falling back to defaults (by the look of it).

In the past these failed even when the sloppy option was given, as
I think they should. I believe the sloppy option is meant to allow
the mount command to still function for mount options (for example
in shared autofs maps) that exist on other Unix implementations but
aren't present in the Linux mount.nfs(8). So, an invalid value
specified for a known mount option is different to an unknown mount
option and should fail appropriately."

See RH bugzilla 486266.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Solder xdr_stream-based XDR decoding functions into the in-kernel mountd
client that are more careful about checking data types and watching for
buffer overflows.  The new MNT3 decoder includes support for auth-flavor
list decoding.

The "_sz" macro for MNT3 replies was missing the size of the file handle.
I've added this back, and included the size of the auth flavor array.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The "intr" mount option has been deprecated for a while, but
/proc/mounts continues to display "nointr" whether "intr" or "nointr"
has been specified for a mount point.

Since these options do not have any effect, simply do not display
them.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

NFSv4 should just ignore the 'nolock' option. It is an NFSv2/v3 thing...
This fixes the Oops in http://bugzilla.kernel.org/show_bug.cgi?id=13330Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

[xfs, btrfs, capifs, shmem don't need BKL, exempt]
Signed-off-by: NAlessio Igor Bogani <abogani@texware.it>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

Push BKL down into ->umount_begin()
Signed-off-by: NAlessio Igor Bogani <abogani@texware.it>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Due to an apparent typo, commit a67d18f8
(NFS: load the rpc/rdma transport module automatically) lead to the
'proto=' mount option doing a double free, while Opt_mountproto leaks a
string.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add NFS mount options to allow the local caching support to be enabled.

The attached patch makes it possible for the NFS filesystem to be told to make
use of the network filesystem local caching service (FS-Cache).

To be able to use this, a recent nfsutils package is required.

There are three variant NFS mount options that can be added to a mount command
to control caching for a mount.  Only the last one specified takes effect:

 (*) Adding "fsc" will request caching.

 (*) Adding "fsc=<string>" will request caching and also specify a uniquifier.

 (*) Adding "nofsc" will disable caching.

For example:

	mount warthog:/ /a -o fsc

The cache of a particular superblock (NFS FSID) will be shared between all
mounts of that volume, provided they have the same connection parameters and
are not marked 'nosharecache'.

Where it is otherwise impossible to distinguish superblocks because all the
parameters are identical, but the 'nosharecache' option is supplied, a
uniquifying string must be supplied, else only the first mount will be
permitted to use the cache.

If there's a key collision, then the second mount will disable caching and give
a warning into the kernel log.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSteve Dickson <steved@redhat.com>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Tested-by: NDaire Byrne <Daire.Byrne@framestore.com>

Add some new NFS I/O counters for FS-Cache doing things for NFS.  A new line is
emitted into /proc/pid/mountstats if caching is enabled that looks like:

	fsc: <rok> <rfl> <wok> <wfl> <unc>

Where <rok> is the number of pages read successfully from the cache, <rfl> is
the number of failed page reads against the cache, <wok> is the number of
successful page writes to the cache, <wfl> is the number of failed page writes
to the cache, and <unc> is the number of NFS pages that have been disconnected
from the cache.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSteve Dickson <steved@redhat.com>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Tested-by: NDaire Byrne <Daire.Byrne@framestore.com>

Define and create superblock-level cache index objects (as managed by
nfs_server structs).

Each superblock object is created in a server level index object and is itself
an index into which inode-level objects are inserted.

Ideally there would be one superblock-level object per server, and the former
would be folded into the latter; however, since the "nosharecache" option
exists this isn't possible.

The superblock object key is a sequence consisting of:

 (1) Certain superblock s_flags.

 (2) Various connection parameters that serve to distinguish superblocks for
     sget().

 (3) The volume FSID.

 (4) The security flavour.

 (5) The uniquifier length.

 (6) The uniquifier text.  This is normally an empty string, unless the fsc=xyz
     mount option was used to explicitly specify a uniquifier.

The key blob is of variable length, depending on the length of (6).

The superblock object is given no coherency data to carry in the auxiliary data
permitted by the cache.  It is assumed that the superblock is always coherent.

This patch also adds uniquification handling such that two otherwise identical
superblocks, at least one of which is marked "nosharecache", won't end up
trying to share the on-disk cache.  It will be possible to manually provide a
uniquifier through a mount option with a later patch to avoid the error
otherwise produced.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSteve Dickson <steved@redhat.com>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Tested-by: NDaire Byrne <Daire.Byrne@framestore.com>

When mounting an NFS/RDMA server with the "-o proto=rdma" or
"-o rdma" options, attempt to dynamically load the necessary
"xprtrdma" client transport module. Doing so improves usability,
while avoiding a static module dependency and any unnecesary
resources.
Signed-off-by: NTom Talpey <tmtalpey@gmail.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add a flag to mark delegations as requiring return, then run a garbage
collector. In the future, this will allow for more flexible delegation
management, where delegations may be marked for return if it turns out
that they are not being referenced.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the admin has specified the "noresvport" option for an NFS mount
point, the kernel's NFS client uses an unprivileged source port for
the main NFS transport.  The kernel's mountd client should use an
unprivileged port in this case as well.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The standard default security setting for NFS is AUTH_SYS.  An NFS
client connects to NFS servers via a privileged source port and a
fixed standard destination port (2049).  The client sends raw uid and
gid numbers to identify users making NFS requests, and the server
assumes an appropriate authority on the client has vetted these
values because the source port is privileged.

On Linux, by default in-kernel RPC services use a privileged port in
the range between 650 and 1023 to avoid using source ports of well-
known IP services.  Using such a small range limits the number of NFS
mount points and the number of unique NFS servers to which a client
can connect concurrently.

An NFS client can use unprivileged source ports to expand the range of
source port numbers, allowing more concurrent server connections and
more NFS mount points.  Servers must explicitly allow NFS connections
from unprivileged ports for this to work.

In the past, bumping the value of the sunrpc.max_resvport sysctl on
the client would permit the NFS client to use unprivileged ports.
Bumping this setting also changes the maximum port number used by
other in-kernel RPC services, some of which still required a port
number less than 1023.

This is exacerbated by the way source port numbers are chosen by the
Linux RPC client, which starts at the top of the range and works
downwards.  It means that bumping the maximum means all RPC services
requesting a source port will likely get an unprivileged port instead
of a privileged one.

Changing this setting effects all NFS mount points on a client.  A
sysadmin could not selectively choose which mount points would use
non-privileged ports and which could not.

Lastly, this mechanism of expanding the limit on the number of NFS
mount points was entirely undocumented.

To address the need for the NFS client to use a large range of source
ports without interfering with the activity of other in-kernel RPC
services, we introduce a new NFS mount option.  This option explicitly
tells only the NFS client to use a non-privileged source port when
communicating with the NFS server for one specific mount point.

This new mount option is called "resvport," like the similar NFS mount
option on FreeBSD and Mac OS X.  A sister patch for nfs-utils will be
submitted that documents this new option in nfs(5).

The default setting for this new mount option requires the NFS client
to use a privileged port, as before.  Explicitly specifying the
"noresvport" mount option allows the NFS client to use an unprivileged
source port for this mount point when connecting to the NFS server
port.

This mount option is supported only for text-based NFS mounts.

[ Sidebar: it is widely known that security mechanisms based on the
  use of privileged source ports are ineffective.  However, the NFS
  client can combine the use of unprivileged ports with the use of
  secure authentication mechanisms, such as Kerberos.  This allows a
  large number of connections and mount points while ensuring a useful
  level of security.

  Eventually we may change the default setting for this option
  depending on the security flavor used for the mount.  For example,
  if the mount is using only AUTH_SYS, then the default setting will
  be "resvport;" if the mount is using a strong security flavor such
  as krb5, the default setting will be "noresvport." ]
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
[Trond.Myklebust@netapp.com: Fixed a bug whereby nfs4_init_client()
was being called with incorrect arguments.]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: convert nfs_mount() to take a single data structure argument to make
it simpler to add more arguments.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u
can be replaced with %pI4
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The iscsi_ibft.c changes are almost certainly a bugfix as the
pointer 'ip' is a u8 *, so they never print the last 8 bytes
of the IPv6 address, and the eight bytes they do print have
a zero byte with them in each 16-bit word.

Other than that, this should cause no difference in functionality.
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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

This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.

This was posted for review some time ago and I believe its been in -mm
since then.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Alexander Viro <aviro@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Bruce observed that nfs_parse_ip_address() will successfully parse an
IPv6 address that looks like this:

  "::1%"

A scope delimiter is present, but there is no scope ID following it.
This is harmless, as it would simply set the scope ID to zero.  However,
in some cases we would like to flag this as an improperly formed
address.

We are now also careful to reject addresses where garbage follows the
address (up to the length of the string), instead of ignoring the
non-address characters; and where the scope ID is nonsense (not a valid
device name, but also not numeric).  Before, both of these cases would
result in a harmless zero scope ID.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The code incorrectly assumes here that the server name (or ip address)
is null-terminated.  This can cause referrals to fail in some cases.

Also support ipv6 addresses.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We plan to use this function elsewhere.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add the following NFS-specific mount options to the parser.

    -o lookupcache=all          /* Default: cache positive & negative
                                   dentries */
    -o lookupcache=pos[itive]   /* Don't cache negative dentries */
    -o lookupcache=none         /* Strict revalidation of all dentries */
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The point of introducing text-based mounts was to allow us to add
functionality without having to worry about legacy binary mount formats.
The mask should be there in order to ensure that binary formats don't start
enabling features that they cannot support. There is no justification for
applying it to the text mount path.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Instead of causing umount requests to block on server->active_wq while the
asynchronous sillyrename deletes are executing, we can use the sb->s_active
counter to obtain a reference to the super_block, and then release that
reference in nfs_async_unlink_release().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Automounter maps can contain mount options valid for other NFS
implementations but not for Linux.  The Linux automounter uses the
mount command's "-s" command line option ("s" for "sloppy") so that
mount requests containing such options are not rejected.

Commit f45663ce attempted to address a
known regression with text-based NFS mount option parsing.  Unrecognized
mount options would cause mount requests to fail, even if the "-s"
option was used on the mount command line.

Unfortunately, this commit was not complete as submitted.  It adds a
new mount option, "sloppy".  But it is missing a hunk, so it now allows
NFS mounts with unrecognized mount options, even if the "sloppy" option
is not present.  This could be a problem if a required critical mount
option such as "sync" is misspelled, for example, and is considered a
regression from 2.6.26.

This patch restores the missing hunk.  Now, the default behavior of
text-based NFS mount options is as before: any unrecognized mount option
will cause the mount to fail.

Please include this in 2.6.27-rc.

Thanks to Neil Brown for reporting this.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Acked-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Jeff, Trond,

The commit

48b605f8 (NFS: implement option checking
when remounting NFS filesystems (resend))

generate an Oops on my platform when rebooting while its root FS on
an NFS share (NFSv3, TCP) :

Unmounting local filesystems...done.
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c3d00000
[00000000] *pgd=a3d72031, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1]
Modules linked in: cpufreq_powersave cpufreq_ondemand cpufreq_userspace cpufreq_conservative ext3 jbd sd_mod pata_pcmcia libata scsi_mod pcmcia loop firmware_class pxafb cfbcopyarea cfbimgblt cfbfillrect pxa2xx_cs pxa2xx_core pcmcia_core snd_pxa2xx_ac97 snd_ac97_codec ac97_bus snd_pxa2xx_pcm snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd isp116x_hcd soundcore rtc_sa1100 snd_page_alloc pxa25x_udc usbcore rtc_ds1307 rtc_core
CPU: 0    Not tainted  (2.6.26-03414-g33af79d1-dirty #15)
PC is at nfs_remount+0x40/0x264
LR is at do_remount_sb+0x158/0x194
pc : [<c00bbf54>]    lr : [<c0076c40>]    psr: 60000013
sp : c2dd1e70  ip : c2dd1e98  fp : c2dd1e94
r10: 00000040  r9 : c3d17000  r8 : c3c3fc40
r7 : 00000000  r6 : 00000000  r5 : c3d2b200  r4 : 00000000
r3 : 00000003  r2 : 00000000  r1 : c2dd1e9c  r0 : c3c3fc00
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 0000397f  Table: a3d00000  DAC: 00000015
Process mount (pid: 1462, stack limit = 0xc2dd0270)
Stack: (0xc2dd1e70 to 0xc2dd2000)
1e60:                                     00000000 c3c3fc00 00000000 00000000
1e80: c3c3fc40 c3d17000 c2dd1ebc c2dd1e98 c0076c40 c00bbf20 c01c61e4 00000001
1ea0: c2dd1ebc 00000001 c3c3fc00 c2dd1ef0 c2dd1ee4 c2dd1ec0 c008c6d8 c0076af4
1ec0: 00000021 00000040 c2dd1ef0 c3d77000 c3eaa000 00000000 c2dd1f6c c2dd1ee8
1ee0: c008d1bc c008c5f8 00000000 c2dd0000 c3c0c320 c3805b38 c002064c 0001f820
1f00: 0001f810 00000001 00000001 00000000 c2dd0000 00000000 c2dd1f34 c2dd1f28
1f20: c005ead8 c005e6f8 c2dd1f44 c2dd1f38 c005eaf8 c005ead0 c2dd1f6c c2dd1f48
1f40: c008ae3c 00000000 c3d77000 0001f810 c0ed0021 c0020ca8 c2dd0000 00000000
1f60: c2dd1fa4 c2dd1f70 c008d2d4 c008d0bc 00000000 0001f810 c2dd1f9c c3eaa000
1f80: c3d17000 00000000 00000000 be8b6aa8 be8b6ad0 00000015 00000000 c2dd1fa8
1fa0: c0020b00 c008d254 00000000 be8b6aa8 0001f810 0001f820 0001f830 c0ed0021
1fc0: 00000000 be8b6aa8 be8b6ad0 00000015 00000000 be8b6ad0 0001f810 be8b6aa8
1fe0: 0001f810 be8b6964 0000aab8 40125124 60000010 0001f810 00000000 00000000
Backtrace:
[<c00bbf14>] (nfs_remount+0x0/0x264) from [<c0076c40>] (do_remount_sb+0x158/0x194)
  r9:c3d17000 r8:c3c3fc40 r7:00000000 r6:00000000 r5:c3c3fc00
r4:00000000
[<c0076ae8>] (do_remount_sb+0x0/0x194) from [<c008c6d8>] (do_remount+0xec/0x118)
  r6:c2dd1ef0 r5:c3c3fc00 r4:00000001
[<c008c5ec>] (do_remount+0x0/0x118) from [<c008d1bc>] (do_mount+0x10c/0x198)
[<c008d0b0>] (do_mount+0x0/0x198) from [<c008d2d4>] (sys_mount+0x8c/0xd4)
[<c008d248>] (sys_mount+0x0/0xd4) from [<c0020b00>] (ret_fast_syscall+0x0/0x2c)
  r7:00000015 r6:be8b6ad0 r5:be8b6aa8 r4:00000000
Code: 0a000086 ea000006 e3530003 8a000004 (e5923000)
---[ end trace 55e1b689cf8c8a6a ]---
------------[ cut here ]------------
WARNING: at kernel/exit.c:966 do_exit+0x3c/0x628()
Modules linked in: cpufreq_powersave cpufreq_ondemand cpufreq_userspace cpufreq_conservative ext3 jbd sd_mod pata_pcmcia libata scsi_mod pcmcia loop firmware_class pxafb cfbcopyarea cfbimgblt cfbfillrect pxa2xx_cs pxa2xx_core pcmcia_core snd_pxa2xx_ac97 snd_ac97_codec ac97_bus snd_pxa2xx_pcm snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd isp116x_hcd soundcore rtc_sa1100 snd_page_alloc pxa25x_udc usbcore rtc_ds1307 rtc_core
[<c0025168>] (dump_stack+0x0/0x14) from [<c0032154>] (warn_on_slowpath+0x4c/0x68)
[<c0032108>] (warn_on_slowpath+0x0/0x68) from [<c003531c>] (do_exit+0x3c/0x628)
  r6:0000000b r5:c3c3dc80 r4:c2dd0000
[<c00352e0>] (do_exit+0x0/0x628) from [<c0025004>] (die+0x2b0/0x30c)
[<c0024d54>] (die+0x0/0x30c) from [<c00270bc>] (__do_kernel_fault+0x6c/0x80)
[<c0027050>] (__do_kernel_fault+0x0/0x80) from [<c00272e0>] (do_page_fault+0x210/0x230)
  r7:c3fa7118 r6:c3c3dc80 r5:c3d166a8 r4:00010000
[<c00270d0>] (do_page_fault+0x0/0x230) from [<c00201ec>] (do_DataAbort+0x3c/0xa0)
[<c00201b0>] (do_DataAbort+0x0/0xa0) from [<c002064c>] (__dabt_svc+0x4c/0x60)
Exception stack(0xc2dd1e28 to 0xc2dd1e70)
1e20:                   c3c3fc00 c2dd1e9c 00000000 00000003 00000000 c3d2b200
1e40: 00000000 00000000 c3c3fc40 c3d17000 00000040 c2dd1e94 c2dd1e98 c2dd1e70
1e60: c0076c40 c00bbf54 60000013 ffffffff
  r8:c3c3fc40 r7:00000000 r6:00000000 r5:c2dd1e5c r4:ffffffff
[<c00bbf14>] (nfs_remount+0x0/0x264) from [<c0076c40>] (do_remount_sb+0x158/0x194)
  r9:c3d17000 r8:c3c3fc40 r7:00000000 r6:00000000 r5:c3c3fc00
r4:00000000
[<c0076ae8>] (do_remount_sb+0x0/0x194) from [<c008c6d8>] (do_remount+0xec/0x118)
  r6:c2dd1ef0 r5:c3c3fc00 r4:00000001
[<c008c5ec>] (do_remount+0x0/0x118) from [<c008d1bc>] (do_mount+0x10c/0x198)
[<c008d0b0>] (do_mount+0x0/0x198) from [<c008d2d4>] (sys_mount+0x8c/0xd4)
[<c008d248>] (sys_mount+0x0/0xd4) from [<c0020b00>] (ret_fast_syscall+0x0/0x2c)
  r7:00000015 r6:be8b6ad0 r5:be8b6aa8 r4:00000000
---[ end trace 55e1b689cf8c8a6a ]---
/etc/rc6.d/S60umountroot: line 17:  1462 Segmentation fault      mount $MOUNT_FORCE_OPT -n -o remount,ro -t dummytype dummydev / 2> /dev/null

The new super.c:nfs_remount function doesn't check the validity of the
options/options4 pointers. Unfortunately, this seems to happend.
The obvious patch seems to check the pointers, and not to do anything if
the happend to be NULL.

Tested on an XScale PXA255 system, latest git.

Regards,

	M.
Signed-off-by: NMarc Zyngier <marc.zyngier@altran.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

The kernel's NFS client mount option parser currently doesn't allow
unrecognized or incorrect mount options.  This prevents misspellings or
incorrectly specified mount options from possibly causing silent data
corruption.

However, NFS mount options are not standardized, so different operating
systems can use differently spelled mount options to support similar
features, or can support mount options which no other operating system
supports.

"Sloppy" mount option parsing, which allows the parser to ignore any
option it doesn't recognize, is needed to support automounters that often
use maps that are shared between heterogenous operating systems.

The legacy mount command ignores the validity of the values of mount
options entirely, except for the "sec=" and "proto=" options.  If an
incorrect value is specified, the out-of-range value is passed to the
kernel; if a value is specified that contains non-numeric characters,
it appears as though the legacy mount command sets that option to zero
(probably incorrect behavior in general).

In any case, this sets a precedent which we will partially follow for
the kernel mount option parser:

	+ if "sloppy" is not set, the parser will be strict about both
	  unrecognized options (same as legacy) and invalid option
	  values (stricter than legacy)

	+ if "sloppy" is set, the parser will ignore unrecognized
	  options and invalid option values (same as legacy)

An "invalid" option value in this case means that either the type
(integer, short, or string) or sign (for integer values) of the specified
value is incorrect.

This patch does two things: it changes the NFS client's mount option
parsing loop so that it parses the whole string instead of failing at
the first unrecognized option or invalid option value.  An unrecognized
option or an invalid option value cause the option to be skipped.

Then, the patch adds a "sloppy" mount option that allows the parsing
to succeed anyway if there were any problems during parsing.  When
parsing a set of options is complete, if there are errors and "sloppy"
was specified, return success anyway.  Otherwise, only return success
if there are no errors.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Set the default security flavor when we set the other mount option
default values for NFSv4.  This cleans up the NFSv4 mount option parsing
path to look like the NFSv2/v3 one.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Set the default security flavor when we set the other mount option default
values.  After this change, only the legacy user-space mount path needs to
set the NFS_MOUNT_SECFLAVOUR flag.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: Refactor the NFS mount option parsing function to extract the
security flavor parsing logic into a separate function.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The remount path does not need to set the port in the server address.
Since it's not really a part of option parsing, move the nfs_set_port()
call to nfs_parse_mount_options()'s callers.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move the UDP/TCP default timeo/retrans settings for text mounts to
nfs_init_timeout_values(), which was were they were always being
initialised (and sanity checked) for binary mounts.
Document the default timeout values using appropriate #defines.

Ensure that we initialise and sanity check the transport protocols that
may have been specified by the user.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add support in the kernel NFS client's address parser for interface
identifiers.

IPv6 link-local addresses require an additional "interface identifier",
which is a network device name or an integer that indexes the array of
local network interfaces.  They are suffixed to the address with a '%'.
For example:

	fe80::215:c5ff:fe3b:e1b2%2

indicates an interface index of 2.  Or

	fe80::215:c5ff:fe3b:e1b2%eth0

indicates that requests should be routed through the eth0 device.
Without the interface ID, link-local addresses are not usable for NFS.

Both the kernel NFS client mount option parser and the mount.nfs command
can take either form.  The mount.nfs command always passes the address
through getnameinfo(3), which usually re-writes interface indices as
device names.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

To make nfs_parse_server_address() more generally useful, allow it to
accept input strings that are not terminated with '\0'.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>