Commit graph

66 commits

Author SHA1 Message Date
Chuck Lever
bcf35617a7 NFS: Show "nointr" mount option
The default "intr" setting is different for NFS and NFSv4.  To avoid
confusion on this issue, don't hide the "nointr" option in /proc/mounts.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:17 -04:00
Chuck Lever
6e88e0618c NFS: Verify server address before invoking in-kernel mount client
Re-order mount option sanity checking slightly to ensure we have a valid
server address *before* trying to do the mountd RPC call.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:14 -04:00
\"Talpey, Thomas\
2cf7ff7a37 NFS: support RDMA mounts
Adds hooks to the string-based NFS mount to support an "rdma" protocol option.

Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:00 -04:00
\"Talpey, Thomas\
56928edd5a NFS - print accurate transport protocol
Use the per-transport strings to display the transport protocol accurately.

Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:55 -04:00
\"Talpey, Thomas\
0896a725a1 NFS/SUNRPC: use transport protocol naming
Instead of an { address family, raw IP protocol number }-tuple, use the
newly-defined RPC identifier when creating clients in the upper layers.

Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:53 -04:00
Trond Myklebust
20c71f5e0f NFSv4: Fix a bug in nfs4_validate_mount_data()
The previous patch introduced a bug when copying the server address.

Also clarify a copy into the auth_flavours array: currently the two
size calculations are equivalent, but we may decide to change the size
of auth_flavors[] at some point.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:31 -04:00
\"Talpey, Thomas\
91ea40b9c6 NFS: use in-kernel mount argument structure for nfsv4 mounts
The user-visible nfs4_mount_data does not contain sufficient data to
describe new mount options, and also is now a legacy structure. Replace
it with the internal nfs_parsed_mount_data for nfsv4 in-kernel use.

Signed-off-by: Tom Talpey <tmt@netapp.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:28 -04:00
\"Talpey, Thomas\
2283f8d6ed NFS: use in-kernel mount argument structure for nfsv[23] mounts
The user-visible nfs_mount_data does not contain sufficient data to
describe new mount options, and also is now a legacy structure. Replace
it with the internal nfs_parsed_mount_data for nfsv[23] in-kernel use.

Signed-off-by: Tom Talpey <tmt@netapp.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:26 -04:00
\"Talpey, Thomas\
6b18eaa082 NFS: move nfs_parsed_mount_data structure definition
In preparation for rearranging the nfs mount argument passing, make the
nfs_parsed_mount_data struct visible across nfs kernel files.

Signed-off-by: Tom Talpey <tmt@netapp.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:23 -04:00
Chuck Lever
0ac83779fa NFS: Add new 'mountaddr=' mount option
I got the 'mounthost=' option wrong - it shouldn't look for an address
value, but rather a hostname value.  However, the in-kernel mount client
and NFS client cannot resolve a hostname by themselves; they rely on
user-land to pass in the resolved address.

Create a new mount option that does take an address so that the mount
program's address can be passed in.  The mount hostname is now ignored
by the kernel.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:06 -04:00
James Lentini
aad7000735 [NFS] [PATCH] NFS: initialize default port in kernel mount client
If no mount server port number is specified, the previous change to the
kernel mount client inadvertently allows the NFS server's port number to be
the used as the mount server's port number. If the user specifies an NFS
server port (-o port=x), the mount will fail.

The fix below sets the mount server's port to 0 if no mount server
port is specified by the user.

Signed-off-by: James Lentini <jlentini@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:04 -04:00
Chuck Lever
efd8340bb1 NFS: Kernel mount client should use async bind
Simplify the in-kernel mount client by using autobind instead of an
explicit call to rpc_getport_sync.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:17:01 -04:00
Jeff Layton
ddc01c0813 [NFS] [PATCH] NFS: show addr=ipaddr in /proc/mounts rather than
A minor thing, but useful when working with a server with multiple
addrs. This looks like it might also be necessary if Miklos' effort
to eliminate /etc/mtab ever comes to fruition.

When displaying mount options in /proc/mounts, the kernel prints
"addr=hostname". This info is redundant since we already have the
hostname displayed as part of the "device" section of the mount. This
patch changes it to display the IP address to which the socket is
connected.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:15:39 -04:00
Alexey Dobriyan
49af7ee181 nfs: fix oops re sysctls and V4 support
NFS unregisters sysctls only if V4 support is compiled in.  However, sysctl
table is not V4 specific, so unregister it always.

Steps to reproduce:

	[build nfs.ko with CONFIG_NFS_V4=n]
	modrobe nfs
	rmmod nfs
	ls /proc/sys

Unable to handle kernel paging request at ffffffff880661c0 RIP:
 [<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
PGD 203067 PUD 207063 PMD 7e216067 PTE 0
Oops: 0000 [1] SMP
CPU 1
Modules linked in: lockd nfs_acl sunrpc
Pid: 3335, comm: ls Not tainted 2.6.23-rc3-bloat #2
RIP: 0010:[<ffffffff802af8e3>]  [<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
RSP: 0018:ffff81007fd93e78  EFLAGS: 00010286
RAX: ffffffff880661c0 RBX: ffffffff80466370 RCX: ffffffff880661c0
RDX: 00000000000014c0 RSI: ffff81007f3ad020 RDI: ffff81007efd8b40
RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff802a8570 R12: ffffffff880661c0
R13: ffff81007e219640 R14: ffff81007efd8b40 R15: ffff81007ded7280
FS:  00002ba25ef03060(0000) GS:ffff81007ff81258(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffffffff880661c0 CR3: 000000007dfaf000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process ls (pid: 3335, threadinfo ffff81007fd92000, task ffff81007d8a0000)
Stack:  ffff81007f3ad150 ffffffff80283f30 ffff81007fd93f48 ffff81007efd8b40
 ffff81007ee00440 0000000422222222 0000000200035593 ffffffff88037e9a
 2222222222222222 ffffffff80466500 ffff81007e416400 ffff81007e219640
Call Trace:
 [<ffffffff80283f30>] filldir+0x0/0xf0
 [<ffffffff80283f30>] filldir+0x0/0xf0
 [<ffffffff802840c7>] vfs_readdir+0xa7/0xc0
 [<ffffffff80284376>] sys_getdents+0x96/0xe0
 [<ffffffff8020bb3e>] system_call+0x7e/0x83

Code: 41 8b 14 24 85 d2 74 dc 49 8b 44 24 08 48 85 c0 74 e7 49 3b
RIP  [<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
 RSP <ffff81007fd93e78>
CR2: ffffffff880661c0
Kernel panic - not syncing: Fatal exception

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-19 11:24:18 -07:00
Chuck Lever
7d1cca7299 NFS: change NFS mount error return when hostname/pathname too long
According to the mount(2) man page, the proper error return code for the
mount(2) system call when the special device name or the mounted-on
directory name is too long is ENAMETOOLONG.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-09-01 10:14:40 -04:00
Chuck Lever
350c73af6a NFS: Off-by-one length error in string handling
The hostname was getting truncated in the new text-based NFS mount API.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-09-01 10:14:40 -04:00
Chuck Lever
fdc6e2c8c0 NFS: Return a real error code from mount(2)
Don't filter the return code from the in-kernel rpcbind or NFS mount
clients.  Return the real error code so that callers of the new NFS
text-based mount API can apply a useful retry strategy.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-09-01 10:14:39 -04:00
Chuck Lever
fdb66ff4ac NFS: mount option parser chokes on proto=
The new text-based NFS mount option parsing logic doesn't recognize any
valid transport protocols due to a silly mistake in the protocol token
matching logic.  This prevents basic mount requests such as:

   mount.nfs server:/export /mnt -o proto=tcp

from working with the new text-based NFS mount API.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-09-01 10:14:38 -04:00
Trond Myklebust
e89a5a43b9 NFS: Fix the mount regression
This avoids the recent NFS mount regression (returning EBUSY when
mounting the same filesystem twice with different parameters).

The best I can do given the constraints appears to be to have the kernel
first look for a superblock that matches both the fsid and the
user-specified mount options, and then spawn off a new superblock if
that search fails.

Note that this is not the same as specifying nosharecache everywhere
since nosharecache will never attempt to match an existing superblock.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Hua Zhong <hzhong@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-31 20:26:45 -07:00
Al Viro
41089644c1 fix broken handling of port=... in NFS option parsing
Obviously broken on little-endian; fortunately, the option is not
frequently used...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[ Hey, sparse is wonderful, but even better than sparse is having people
  like Al that actually _run_ it and fix bugs using it.    - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-22 11:15:18 -07:00
Jeff Layton
0a87cf128f NFSv4: handle lack of clientaddr in option string
If a NFSv4 mount is attempted  with string based options, and the
option string doesn't contain a clientaddr= option, the kernel will
currently oops. Check for this situation and return a proper error.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-19 15:21:40 -04:00
Rusty Russell
8e1f936b73 mm: clean up and kernelify shrinker registration
I can never remember what the function to register to receive VM pressure
is called.  I have to trace down from __alloc_pages() to find it.

It's called "set_shrinker()", and it needs Your Help.

1) Don't hide struct shrinker.  It contains no magic.
2) Don't allocate "struct shrinker".  It's not helpful.
3) Call them "register_shrinker" and "unregister_shrinker".
4) Call the function "shrink" not "shrinker".
5) Reduce the 17 lines of waffly comments to 13, but document it properly.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Chinner <dgc@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:00 -07:00
Trond Myklebust
275a5d24bf NFS: Error when mounting the same filesystem with different options
Unless the user sets the NFS_MOUNT_NOSHAREDCACHE mount flag, we should
return EBUSY if the filesystem is already mounted on a superblock that
has set conflicting mount options.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:48 -04:00
Trond Myklebust
75180df2ed NFS: Add the mount option "nosharecache"
Prior to David Howell's mount changes in 2.6.18, users who mounted
different directories which happened to be from the same filesystem on the
server would get different super blocks, and hence could choose different
mount options. As long as there were no hard linked files that crossed from
one subtree to another, this was quite safe.
Post the changes, if the two directories are on the same filesystem (have
the same 'fsid'), they will share the same super block, and hence the same
mount options.

Add a flag to allow users to elect not to share the NFS super block with
another mount point, even if the fsids are the same. This will allow
users to set different mount options for the two different super blocks, as
was previously possible. It is still up to the user to ensure that there
are no cache coherency issues when doing this, however the default
behaviour will be to share super blocks whenever two paths result in
the same fsid.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:48 -04:00
Chuck Lever
8007122520 NFS: Add support for mounting NFSv4 file systems with string options
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:48 -04:00
Chuck Lever
136d558ce7 NFS: Add final pieces to support in-kernel mount option parsing
Hook in final components required for supporting in-kernel mount option
parsing for NFSv2 and NFSv3 mounts.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:48 -04:00
Chuck Lever
0076d7b7ba NFS: Introduce generic mount client API
For NFSv2 and v3 mounts, the first step is to contact the server's MOUNTD
and request the file handle for the root of the mounted share.  Add a
function to the NFS client that handles this operation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:47 -04:00
Chuck Lever
bf0fd7680f NFS: Add enums and match tables for mount option parsing
This generic infrastructure works for both NFS and NFSv4 mounts.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:47 -04:00
Chuck Lever
f0768ebd09 NFS: Introduce nfs4_validate_mount_options
Refactor NFSv4 mount processing to break out mount data validation
in the same way it's broken out in the NFSv2/v3 mount path.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:45 -04:00
Chuck Lever
5df36e78da NFS: Clean up nfs_validate_mount_data
Move error handling code out of the main code path.  The switch statement
was also improperly indented, according to Documentation/CodingStyle.  This
prepares nfs_validate_mount_data for the addition of option string parsing.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:45 -04:00
Chuck Lever
fc50d58fd0 NFS: Clean-up: Refactor IP address sanity checks in NFS client
NFS and NFSv4 mounts can now share server address sanity checking.  And, it
provides an easy mechanism for adding IPv6 address checking at some later
point.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:44 -04:00
Chuck Lever
4d81cd1611 NFS: Clean-up: fix a compiler warning in fs/nfs/super.c
/home/cel/linux/fs/nfs/super.c: In function 'nfs_pseudoflavour_to_name':
/home/cel/linux/fs/nfs/super.c:270: warning: comparison between signed and unsigned

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:44 -04:00
Chuck Lever
0655960f76 NFS: Clean up error handling in nfs_get_sb
The error return logic in nfs_get_sb now matches nfs4_get_sb, and is more maintainable.
A subsequent patch will take advantage of this simplification.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:44 -04:00
Chuck Lever
29eb981a3b NFS: Clean-up: Replace nfs_copy_user_string with strndup_user
The new string utility function strndup_user can be used instead of
nfs_copy_user_string, eliminating an unnecessary duplication of function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:44 -04:00
Chuck Lever
5680d48be8 NFS: Clean-up: Define macros for maximum host and export path name lengths
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:44 -04:00
Trond Myklebust
fc6ae3cf48 NFS: Re-enable forced umounts
They disappeared some time around 2.6.18.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:25 -04:00
Steve Dickson
74dd34e6e8 NFS: Added support to turn off the NFSv3 READDIRPLUS RPC.
READDIRPLUS can be a performance hindrance when the client is working with
large directories. In addition, some servers still have bugs in their
implementations (e.g. Tru64 returns wrong values for the fsid).

Add a mount flag to enable users to turn it off at mount time following the
implementation in Apple's NFS client.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-04-30 22:17:16 -07:00
Amnon Aaronsohn
1a0ba9ae48 NFS: statfs error-handling fix
The nfs statfs function returns a success code on error, and fills the
output buffer with invalid values.  The attached patch makes it return a
correct error code instead.

Signed-off-by: Amnon Aaronsohn <amnonaar@gmail.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
 (Modified patch to reinstate the dprintk())
2007-04-30 22:17:02 -07:00
Peter Zijlstra
89a09141df [PATCH] nfs: fix congestion control
The current NFS client congestion logic is severly broken, it marks the
backing device congested during each nfs_writepages() call but doesn't
mirror this in nfs_writepage() which makes for deadlocks.  Also it
implements its own waitqueue.

Replace this by a more regular congestion implementation that puts a cap on
the number of active writeback pages and uses the bdi congestion waitqueue.

Also always use an interruptible wait since it makes sense to be able to
SIGKILL the process even for mounts without 'intr'.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-16 19:25:05 -07:00
Trond Myklebust
d9bc125caf Merge branch 'master' of /home/trondmy/kernel/linux-2.6/
Conflicts:

	net/sunrpc/auth_gss/gss_krb5_crypto.c
	net/sunrpc/auth_gss/gss_spkm3_token.c
	net/sunrpc/clnt.c

Merge with mainline and fix conflicts.
2007-02-12 22:43:25 -08:00
Josef 'Jeff' Sipek
ee9b6d61a2 [PATCH] Mark struct super_operations const
This patch is inspired by Arjan's "Patch series to mark struct
file_operations and struct inode_operations const".

Compile tested with gcc & sparse.

Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:47 -08:00
Adrian Bunk
b5d5dfbd59 [PATCH] include/linux/nfsd/const.h: remove NFS_SUPER_MAGIC
NFS_SUPER_MAGIC is already defined in include/linux/magic.h

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:36 -08:00
Trond Myklebust
f2d0d85e58 NFSv4: Fix Oops in nfs4_create_referral_server
The filehandle that is passed into nfs4_create_referral_server is
not initialised. The expectation is that nfs4_create_referral_server will
initialise it, and return it to the caller.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-02-03 15:35:03 -08:00
Trond Myklebust
575b5c7870 [PATCH] NFSv4: Fix thinko in fs/nfs/super.c
Duh. addr.sin_port should be in network byte order.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:38 -07:00
Dave Jones
038b0a6d8d Remove all inclusions of <linux/config.h>
kbuild explicitly includes this at build time.

Signed-off-by: Dave Jones <davej@redhat.com>
2006-10-04 03:38:54 -04:00
Mark Fasheh
349457ccf2 [PATCH] Allow file systems to manually d_move() inside of ->rename()
Some file systems want to manually d_move() the dentries involved in a
rename.  We can do this by making use of the FS_ODD_RENAME flag if we just
have nfs_rename() unconditionally do the d_move().  While there, we rename
the flag to be more descriptive.

OCFS2 uses this to protect that part of the rename operation with a cluster
lock.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-09-24 13:50:45 -07:00
Trond Myklebust
51b6ded4d9 NFSv4: When mounting with a port=0 argument, substitute port=2049
RFC3530 states that the registered port 2049 for the NFS protocol should be
the default configuration in order to allow clients not to use the RPC
binding protocols.
If the mount program sends us a port=0, we therefore substitute port=2049.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:25:04 -04:00
Trond Myklebust
5dd3177ae5 NFSv4: Fix a use-after-free issue with the nfs server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:54 -04:00
Trond Myklebust
36b15c54cd NFS: Ensure NFSv2/v3 mounts respect the NFS_MOUNT_SECFLAVOUR flag
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:38 -04:00
David Howells
54ceac4515 NFS: Share NFS superblocks per-protocol per-server per-FSID
The attached patch makes NFS share superblocks between mounts from the same
server and FSID over the same protocol.

It does this by creating each superblock with a false root and returning the
real root dentry in the vfsmount presented by get_sb(). The root dentry set
starts off as an anonymous dentry if we don't already have the dentry for its
inode, otherwise it simply returns the dentry we already have.

We may thus end up with several trees of dentries in the superblock, and if at
some later point one of anonymous tree roots is discovered by normal filesystem
activity to be located in another tree within the superblock, the anonymous
root is named and materialises attached to the second tree at the appropriate
point.

Why do it this way? Why not pass an extra argument to the mount() syscall to
indicate the subpath and then pathwalk from the server root to the desired
directory? You can't guarantee this will work for two reasons:

 (1) The root and intervening nodes may not be accessible to the client.

     With NFS2 and NFS3, for instance, mountd is called on the server to get
     the filehandle for the tip of a path. mountd won't give us handles for
     anything we don't have permission to access, and so we can't set up NFS
     inodes for such nodes, and so can't easily set up dentries (we'd have to
     have ghost inodes or something).

     With this patch we don't actually create dentries until we get handles
     from the server that we can use to set up their inodes, and we don't
     actually bind them into the tree until we know for sure where they go.

 (2) Inaccessible symbolic links.

     If we're asked to mount two exports from the server, eg:

	mount warthog:/warthog/aaa/xxx /mmm
	mount warthog:/warthog/bbb/yyy /nnn

     We may not be able to access anything nearer the root than xxx and yyy,
     but we may find out later that /mmm/www/yyy, say, is actually the same
     directory as the one mounted on /nnn. What we might then find out, for
     example, is that /warthog/bbb was actually a symbolic link to
     /warthog/aaa/xxx/www, but we can't actually determine that by talking to
     the server until /warthog is made available by NFS.

     This would lead to having constructed an errneous dentry tree which we
     can't easily fix. We can end up with a dentry marked as a directory when
     it should actually be a symlink, or we could end up with an apparently
     hardlinked directory.

     With this patch we need not make assumptions about the type of a dentry
     for which we can't retrieve information, nor need we assume we know its
     place in the grand scheme of things until we actually see that place.

This patch reduces the possibility of aliasing in the inode and page caches for
inodes that may be accessed by more than one NFS export. It also reduces the
number of superblocks required for NFS where there are many NFS exports being
used from a server (home directory server + autofs for example).

This in turn makes it simpler to do local caching of network filesystems, as it
can then be guaranteed that there won't be links from multiple inodes in
separate superblocks to the same cache file.

Obviously, cache aliasing between different levels of NFS protocol could still
be a problem, but at least that gives us another key to use when indexing the
cache.

This patch makes the following changes:

 (1) The server record construction/destruction has been abstracted out into
     its own set of functions to make things easier to get right.  These have
     been moved into fs/nfs/client.c.

     All the code in fs/nfs/client.c has to do with the management of
     connections to servers, and doesn't touch superblocks in any way; the
     remaining code in fs/nfs/super.c has to do with VFS superblock management.

 (2) The sequence of events undertaken by NFS mount is now reordered:

     (a) A volume representation (struct nfs_server) is allocated.

     (b) A server representation (struct nfs_client) is acquired.  This may be
     	 allocated or shared, and is keyed on server address, port and NFS
     	 version.

     (c) If allocated, the client representation is initialised.  The state
     	 member variable of nfs_client is used to prevent a race during
     	 initialisation from two mounts.

     (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find
     	 the root filehandle for the mount (fs/nfs/getroot.c).  For NFS2/3 we
     	 are given the root FH in advance.

     (e) The volume FSID is probed for on the root FH.

     (f) The volume representation is initialised from the FSINFO record
     	 retrieved on the root FH.

     (g) sget() is called to acquire a superblock.  This may be allocated or
     	 shared, keyed on client pointer and FSID.

     (h) If allocated, the superblock is initialised.

     (i) If the superblock is shared, then the new nfs_server record is
     	 discarded.

     (j) The root dentry for this mount is looked up from the root FH.

     (k) The root dentry for this mount is assigned to the vfsmount.

 (3) nfs_readdir_lookup() creates dentries for each of the entries readdir()
     returns; this function now attaches disconnected trees from alternate
     roots that happen to be discovered attached to a directory being read (in
     the same way nfs_lookup() is made to do for lookup ops).

     The new d_materialise_unique() function is now used to do this, thus
     permitting the whole thing to be done under one set of locks, and thus
     avoiding any race between mount and lookup operations on the same
     directory.

 (4) The client management code uses a new debug facility: NFSDBG_CLIENT which
     is set by echoing 1024 to /proc/net/sunrpc/nfs_debug.

 (5) Clone mounts are now called xdev mounts.

 (6) Use the dentry passed to the statfs() op as the handle for retrieving fs
     statistics rather than the root dentry of the superblock (which is now a
     dummy).

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:37 -04:00