Commit Graph

776 Commits

Author SHA1 Message Date
Chuck Lever d4d3c50749 NFS: Enable NFS client to generate CLIENTID strings with IPv6 addresses
We recently added methods to RPC transports that provide string versions of
the remote peer address information.  Convert the NFSv4 SETCLIENTID
procedure to use those methods instead of building the client ID out of
whole cloth.

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>
2008-01-30 02:05:51 -05:00
Chuck Lever cc38bac3a0 NFS: Ensure NFSv4 SETCLIENTID send buffer is large enough
Ensure that the RPC buffer size specified for NFSv4 SETCLIENTID procedures
matches what we are encoding into the buffer.  See the definition of
struct nfs4_setclientid {} and the encode_setclientid() function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:51 -05:00
Trond Myklebust 40c553193d NFS: Remove the redundant nfs_client->cl_nfsversion
We can get the same information from the rpc_ops structure instead.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:49 -05:00
Trond Myklebust c81468a1a7 NFS: Clean up the nfs_find_client function.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:48 -05:00
Trond Myklebust 3a498026ee NFS: Clean up the nfs_client initialisation
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:48 -05:00
Trond Myklebust bfc69a4566 NFS: define a function to update nfsi->cache_change_attribute
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:47 -05:00
Chuck Lever 5cce428d95 NFS: Remove an unneeded check in decode_compound_header_arg()
Clean up:  The header tag length is unsigned, so checking that it is less
than zero is unnecessary.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:46 -05:00
Chuck Lever d45273ed6f NFS: Clean up address comparison in __nfs_find_client()
The address comparison in the __nfs_find_client() function is deceptive.
It uses a memcmp() to check a pair of u32 fields for equality.  Not only is
this inefficient, but usually memcmp() is used for comparing two *whole*
sockaddr_in's (which includes comparisons of the address family and port
number), so it's easy to mistake the comparison here for a whole sockaddr
comparison, which it isn't.

So for clarity and efficiency, we replace the memcmp() with a simple test
for equality between the two s_addr fields.  This should have no
behavioral effect.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:46 -05:00
Chuck Lever 6a0ed1de8e NFS: Clean up: copy hostname with kstrndup during mount processing
Clean up: mount option parsing uses kstrndup in several places, rather than
using kzalloc.  Replace the few remaining uses of kzalloc with kstrndup,
for consistency.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:46 -05:00
Chuck Lever e887cbcf91 NFS: Remove support for the 'mountprog' option
Remove the mount option that allows users to specify an alternate mountd
program number.  The client hasn't support setting an alternate mountd
program number for a very long time.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:46 -05:00
Chuck Lever ad879cef85 NFS: Remove support for the 'nfsprog' option
Remove the mount option that allows users to specify an alternate NFS
program number.  The client hasn't support setting an alternate NFS
program number for a very long time.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:45 -05:00
Chuck Lever 0eb2574121 NFS: Ensure that NFS version 4 mounts use NFS_PORT if nfsport wasn't set
Text-based mount option parsing introduced a minor regression in the
behavior of NFS version 4 mounts.  NFS version 4 is not supposed to require
a running rpcbind service on the server in order for a mount to succeed.

In other words, if the mount options don't specify a port number, the port
number is supposed to default to 2049.  For earlier versions of NFS, the
default port number was zero in order to cause the RPC client to autobind
to the server's NFS service.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:45 -05:00
Chuck Lever 28c494c5c8 NFS: Prevent nfs_getattr() hang during heavy write workloads
POSIX requires that ctime and mtime, as reported by the stat(2) call,
reflect the activity of the most recent write(2).  To that end, nfs_getattr()
flushes pending dirty writes to a file before doing a GETATTR to allow the
NFS server to set the file's size, ctime, and mtime properly.

However, nfs_getattr() can be starved when a constant stream of application
writes to a file prevents nfs_wb_nocommit() from completing.  This usually
results in hangs of programs doing a stat against an NFS file that is being
written.  "ls -l" is a common victim of this behavior.

To prevent starvation, hold the file's i_mutex in nfs_getattr() to
freeze applications writes temporarily so the client can more quickly obtain
clean values for a file's size, mtime, and ctime.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:45 -05:00
Chuck Lever 464ad6b1ad NFS: Change sign of some loop indices in nfs4xdr.c
Nit: Eliminate some mixed sign comparisons in loop indices.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:44 -05:00
Chuck Lever bcecff77a9 NFS: Use unsigned intermediates for manipulating header lengths (NFSv4 XDR)
Clean up: prevent length underflow and mixed sign comparison when
unmarshalling NFS version 4 getacl, readdir, and readlink replies.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:44 -05:00
Chuck Lever c957c526ef NFS: Use unsigned intermediates for manipulating header lengths (NFSv3 XDR)
Clean up: prevent length underflow and mixed sign comparisons when
unmarshalling NFS version 3 read, readdir, and readlink replies.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:44 -05:00
Chuck Lever 6232dbbcff NFS: Use unsigned intermediates for manipulating header lengths (NFSv2 XDR)
Clean up: prevent length underflow and mixed sign comparisons when
unmarshalling NFS version 2 read, readdir, and readlink replies.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:44 -05:00
Chuck Lever 8a8c74bf94 NFS: Ensure nfs_wcc_update_inode always converts file size to loff_t
The nfs_wcc_update_inode() function omits logic to convert the type of
the NFS on-the-wire value of a file's size (__u64) to the type of file
size value stored in struct inode (loff_t, which is signed).

Everywhere else in the NFS client I checked already correctly converts the
file size type.

This effects only very large files.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:43 -05:00
Trond Myklebust 0773769191 NFS/SUNRPC: Convert users of rpc_init_task+rpc_execute to rpc_run_task()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:39 -05:00
Trond Myklebust 5138fde011 NFS/SUNRPC: Convert all users of rpc_call_setup()
Replace use of rpc_call_setup() with rpc_init_task(), and in cases where we
need to initialise task->tk_action, with rpc_call_start().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:32 -05:00
Trond Myklebust bdc7f021f3 NFS: Clean up the (commit|read|write)_setup() callback routines
Move the common code for setting up the nfs_write_data and nfs_read_data
structures into fs/nfs/read.c, fs/nfs/write.c and fs/nfs/direct.c.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:32 -05:00
Trond Myklebust 3ff7576dda SUNRPC: Clean up the initialisation of priority queue scheduling info.
We want the default scheduling priority (priority == 0) to remain
RPC_PRIORITY_NORMAL.

Also ensure that the priority wait queue scheduling is per process id
instead of sometimes being per thread, and sometimes being per inode.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:30 -05:00
Trond Myklebust c970aa85e7 SUNRPC: Clean up rpc_run_task
Make it use the new task initialiser structure instead of acting as a
wrapper.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:30 -05:00
Trond Myklebust 84115e1cd4 SUNRPC: Cleanup of rpc_task initialisation
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:30 -05:00
Steve Dickson ef818a28fa NFS: Stop sillyname renames and unmounts from racing
Added an active/deactive mechanism to the nfs_server structure
allowing async operations to hold off umount until the
operations are done.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:24 -05:00
Trond Myklebust 2f74c0a056 NFSv4: Clean up the OPEN/CLOSE serialisation code
Reduce the time spent locking the rpc_sequence structure by queuing the
nfs_seqid only when we are ready to take the lock (when calling
nfs_wait_on_sequence).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:24 -05:00
Trond Myklebust acee478afc NFS: Clean up the write request locking.
Ensure that we set/clear NFS_PAGE_TAG_LOCKED when the nfs_page is hashed.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:24 -05:00
Trond Myklebust 8b1f9ee56e NFS: Optimise nfs_vm_page_mkwrite()
The current model locks the page twice for no good reason. Optimise by
inlining the parts of nfs_write_begin()/nfs_write_end() that we care about.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:23 -05:00
Trond Myklebust 77f111929d NFS: Ensure that we eject stale inodes as soon as possible
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:22 -05:00
Trond Myklebust d45b9d8baf NFS: Handle -ENOENT errors in unlink()/rmdir()/rename()
If the server returns an ENOENT error, we still need to do a d_delete() in
order to ensure that the dentry is deleted.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:22 -05:00
Trond Myklebust 609005c319 NFS: Sillyrename: in the case of a race, check aliases are really positive
In nfs_do_call_unlink() we check that we haven't raced, and that lookup()
hasn't created an aliased dentry to our sillydeleted dentry. If somebody
has deleted the file on the server and the lookup() resulted in a negative
dentry, then ignore...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:22 -05:00
Trond Myklebust fccca7fc6a NFS: Fix a sillyrename race...
Ensure that readdir revalidates its data cache after blocking on
sillyrename.

Also fix a typo in nfs_do_call_unlink(): swap the ^= for an |=. The result
is the same, since we've already checked that the flag is unset, but it
makes the code more readable.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:21 -05:00
Trond Myklebust d0dc3701cb NFSv4: Give the lock stateid its own sequence queue
Sharing the open sequence queue causes a deadlock when we try to take
both a lock sequence id and and open sequence id.

This fixes the regression reported by Dimitri Puzin and Jeff Garzik: See

	http://bugzilla.kernel.org/show_bug.cgi?id=9712

for details.

Reported-and-tested-by: Dimitri Puzin <bugs@psycast.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-10 13:35:32 -08:00
Trond Myklebust e6e21970ba NFSv4: Fix open_to_lock_owner sequenceid allocation...
NFSv4 file locking is currently completely broken since it doesn't respect
the OPEN sequencing when it is given an unconfirmed lock_owner and needs to
do an open_to_lock_owner. Worse: it breaks the sunrpc rules by doing a
GFP_KERNEL allocation inside an rpciod callback.

Fix is to preallocate the open seqid structure in nfs4_alloc_lockdata if we
see that the lock_owner is unconfirmed.
Then, in nfs4_lock_prepare() we wait for either the open_seqid, if
the lock_owner is still unconfirmed, or else fall back to waiting on the
standard lock_seqid.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-03 09:37:17 -05:00
Trond Myklebust bb22629ee8 NFSv4: nfs4_open_confirm must not set the open_owner as confirmed on error
RFC3530 states that the open_owner is confirmed if and only if the client
sends an OPEN_CONFIRM request with the appropriate sequence id and stateid
within the lease period.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-03 09:37:17 -05:00
Trond Myklebust b274b48f3e NFSv4: Fix circular locking dependency in nfs4_kill_renewd
Erez Zadok reports:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.24-rc6-unionfs2 #80
-------------------------------------------------------
umount.nfs4/4017 is trying to acquire lock:
 (&(&clp->cl_renewd)->work){--..}, at: [<c0223e53>]
__cancel_work_timer+0x83/0x17f

but task is already holding lock:
 (&clp->cl_sem){----}, at: [<f8879897>] nfs4_kill_renewd+0x17/0x29 [nfs]

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&clp->cl_sem){----}:
       [<c0230699>] __lock_acquire+0x9cc/0xb95
       [<c0230c39>] lock_acquire+0x5f/0x78
       [<c0397cb8>] down_read+0x3a/0x4c
       [<f88798e6>] nfs4_renew_state+0x1c/0x1b8 [nfs]
       [<c0223821>] run_workqueue+0xd9/0x1ac
       [<c0224220>] worker_thread+0x7a/0x86
       [<c0226b49>] kthread+0x3b/0x62
       [<c02033a3>] kernel_thread_helper+0x7/0x10
       [<ffffffff>] 0xffffffff

-> #0 (&(&clp->cl_renewd)->work){--..}:
       [<c0230589>] __lock_acquire+0x8bc/0xb95
       [<c0230c39>] lock_acquire+0x5f/0x78
       [<c0223e87>] __cancel_work_timer+0xb7/0x17f
       [<c0223f5a>] cancel_delayed_work_sync+0xb/0xd
       [<f887989e>] nfs4_kill_renewd+0x1e/0x29 [nfs]
       [<f885a8f6>] nfs_free_client+0x37/0x9e [nfs]
       [<f885ab20>] nfs_put_client+0x5d/0x62 [nfs]
       [<f885ab9a>] nfs_free_server+0x75/0xae [nfs]
       [<f8862672>] nfs4_kill_super+0x27/0x2b [nfs]
       [<c0258aab>] deactivate_super+0x3f/0x51
       [<c0269668>] mntput_no_expire+0x42/0x67
       [<c025d0e4>] path_release_on_umount+0x15/0x18
       [<c0269d30>] sys_umount+0x1a3/0x1cb
       [<c0269d71>] sys_oldumount+0x19/0x1b
       [<c02026ca>] sysenter_past_esp+0x5f/0xa5
       [<ffffffff>] 0xffffffff

Looking at the code, it would seem that taking the clp->cl_sem in
nfs4_kill_renewd is completely redundant, since we're already guaranteed to
have exclusive access to the nfs_client (we're shutting down).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-03 09:37:16 -05:00
Trond Myklebust e9cc6c234b NFS: Fix a possible Oops in fs/nfs/super.c
Sigh... commit 4584f520e1 (NFS: Fix NFS
mountpoint crossing...) had a slight flaw: server can be NULL if sget()
returned an existing superblock.

Fix the fix by dereferencing s->s_fs_info.

Thanks to Coverity/Adrian Bunk and Frank Filz for spotting the bug.
(See http://bugzilla.kernel.org/show_bug.cgi?id=9647)

Also add in the same namespace Oops fix for NFSv4 in both the mountpoint
crossing case, and the referral case.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-03 09:37:11 -05:00
Trond Myklebust a10db50a4a NFS: Fix an Oops in NFS unmount
Ensure that the dummy 'root dentry' is invisible to d_find_alias(). If not,
then it may be spliced into the tree if a parent directory from the same
filesystem gets mounted at a later time.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-12-12 11:12:15 -05:00
Trond Myklebust a5576cfa5c Revert "NFS: Ensure we return zero if applications attempt to write zero bytes"
This reverts commit b9148c6b80.

On Wed, 12 Dec 2007 10:57:30 -0500, Chuck Lever wrote
> commit b9148c6b should be reverted.  It was recently forward-ported
> from some years-old patches, and is clearly not needed now.
>
> On Dec 11, 2007, at 5:21 PM, Adrian Bunk wrote:
>
>> This code became dead after commit
>> b9148c6b80
>> (which BTW doesn't seem to have changed any behaviour) and can
>> therefore
>> be removed.
>>
>> Spotted by the Coverity checker.
>>
>> Signed-off-by: Adrian Bunk <bunk@kernel.org>
>>
>> ---
>> --- linux-2.6/fs/nfs/direct.c.old     2007-12-02 21:54:53.000000000 +0100
>> +++ linux-2.6/fs/nfs/direct.c 2007-12-02 21:55:10.000000000 +0100
>> @@ -897,15 +897,12 @@ ssize_t nfs_file_direct_write(struct kio
>>       if (!count)
>>               goto out;       /* return 0 */
>>
>>       retval = -EINVAL;
>>       if ((ssize_t) count < 0)
>>               goto out;
>> -     retval = 0;
>> -     if (!count)
>> -             goto out;
>>
>>       retval = nfs_sync_mapping(mapping);
>>       if (retval)
>>               goto out;
>>
>>       retval = nfs_direct_write(iocb, iov, nr_segs, pos, count);
>>

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-12-12 11:08:33 -05:00
Trond Myklebust 5cef338b30 NFSv2/v3: Fix a memory leak when using -onolock
Neil Brown said:
> Hi Trond,
> 
> We found that a machine which made moderately heavy use of
> 'automount' was leaking some nfs data structures - particularly the
> 4K allocated by rpc_alloc_iostats.
> It turns out that this only happens with filesystems with -onolock
> set.

> The problem is that if NFS_MOUNT_NONLM is set, nfs_start_lockd doesn't
> set server->destroy, so when the filesystem is unmounted, the
> ->client_acl is not shutdown, and so several resources are still
> held.  Multiple mount/umount cycles will slowly eat away memory
> several pages at a time.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NeilBrown <neilb@suse.de>
2007-12-11 22:01:56 -05:00
Trond Myklebust 4584f520e1 NFS: Fix NFS mountpoint crossing...
The check that was added to nfs_xdev_get_sb() to work around broken
servers, works fine for NFSv2, but causes mountpoint crossing on NFSv3 to
always return ESTALE.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-12-11 19:01:45 -05:00
Chuck Lever 02fe494619 NFS: Clean up new multi-segment direct I/O changes
Simplify calling sequence of nfs_direct_{read,write}_schedule(), and
rename them to reflect their new role.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-26 16:32:40 -05:00
Chuck Lever b9148c6b80 NFS: Ensure we return zero if applications attempt to write zero bytes
A zero byte count direct write request should be a successful no-op, not an
error.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-26 16:32:38 -05:00
Chuck Lever c216fd708e NFS: Support multiple segment iovecs in the NFS direct I/O path
Allow applications to perform asynchronous scatter-gather direct I/O
to NFS files.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-26 16:32:36 -05:00
Chuck Lever 19f737879c NFS: Introduce iovec I/O helpers to fs/nfs/direct.c
Add helpers that iterate over multi-segment iovecs.  These will
be used to support multi-segment scatter/gather direct I/O in a
later patch.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-26 16:32:35 -05:00
Adrian Bunk 4c30d56edc NFS: fs/nfs/dir.c should #include "internal.h"
Every file should include the headers containing the prototypes for its global
functions (in this case nfs_access_cache_shrinker()).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-26 16:24:49 -05:00
Adrian Bunk 5334eb13d4 NFS: make nfs_wb_page_priority() static
nfs_wb_page_priority() can now become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-26 16:24:48 -05:00
Russell King f16c960332 NFS: mount failure causes bad page state
While testing a kernel based upon ecd744eec3
(with wrong boot arguments), I got the following bad page state entry while
NFS was trying to mount it's rootfs:

IP-Config: Complete:
      device=eth0, addr=192.168.1.101, mask=255.255.255.0, gw=255.255.255.255,
     host=192.168.1.101, domain=, nis-domain=(none),
     bootserver=192.168.1.100, rootserver=192.168.1.100, rootpath=
Looking up port of RPC 100003/2 on 192.168.1.100
rpcbind: server 192.168.1.100 not responding, timed out
Root-NFS: Unable to get nfsd port number from server, using default
Looking up port of RPC 100005/1 on 192.168.1.100
rpcbind: server 192.168.1.100 not responding, timed out
Root-NFS: Unable to get mountd port number from server, using default
mount: server 192.168.1.100 not responding, timed out
Root-NFS: Server returned error -5 while mounting /nfs/rootfs/
VFS: Unable to mount root fs via NFS, trying floppy.
Bad page state in process 'swapper'
page:c02b1260 flags:0x00000400 mapping:00000000 mapcount:0 count:0
Trying to fix it up, but a reboot is needed
Backtrace:
[<c0023e34>] (dump_stack+0x0/0x14) from [<c0062570>] (bad_page+0x70/0xac)
[<c0062500>] (bad_page+0x0/0xac) from [<c0064914>] (free_hot_cold_page+0x80/0x178)
[<c0064894>] (free_hot_cold_page+0x0/0x178) from [<c0064a74>] (free_hot_page+0x14/0x18)
[<c0064a60>] (free_hot_page+0x0/0x18) from [<c0067078>] (put_page+0xf8/0x154)
[<c0066f80>] (put_page+0x0/0x154) from [<c007dbc8>] (kfree+0xc8/0xd0)
[<c007db00>] (kfree+0x0/0xd0) from [<c00cbb54>] (nfs_get_sb+0x230/0x710)
[<c00cb924>] (nfs_get_sb+0x0/0x710) from [<c0084334>] (vfs_kern_mount+0x58/0xac)[<c00842dc>] (vfs_kern_mount+0x0/0xac) from [<c00843c0>] (do_kern_mount+0x38/0xf4)
[<c0084388>] (do_kern_mount+0x0/0xf4) from [<c0099c7c>] (do_mount+0x1e8/0x614)
...

This seems to be caused by use of an uninitialised structure due to NULL
options being passed to nfs_validate_mount_data().  Ensure that the
parsed mount data is always initialised.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
     (Trond: added fix for the same bug in nfs4_validate_mount_data()).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-26 16:24:22 -05:00
Neil Brown 4c1fe2f78a kernel BUG at fs/nfs/namespace.c:108! - can be triggered by bad server
Hi Trond,

I have discovered that the BUG_ON in nfs_follow_mountpoint:

	BUG_ON(IS_ROOT(dentry));

can be triggered by a misbehaving server.

What happens is the client does a lookup and discoveres that the named
directory has a different fsid, so it initiates a mount.
It then performs a GETATTR on the mounted directory and gets a
different fsid again (due to a bug in the NFS server).
This causes nfs_follow_mountpoint to be called on the newly mounted
root, which triggers the BUG_ON.

To duplicate this, have a directory which contains some mountpoints,
and export that directory with the "crossmnt" flag using nfs-utils
1.1.1 (or 1.1.0 I think)

The GETATTR on the root of the mounted filesystem will return the
information for the top exportpoint, while a lookup will return the
correct information.  This difference causes the NFS client to BUG.

I think the best way to fix this is to trap this possibility early, so
just before completing the mount in the NFS client, check that it isn't
going to use nfs_mountpoint_inode_operations.
As long as i_op will never change once set (is that true?), this
should be adequately safe.

The following patch shows a possible approach, and it works for me.
i.e. when the NFS server is misbehaving, I get ESTALE on those
mountpoints, while when the NFS server is working correctly, I get
correct behaviour on the client.

NeilBrown

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-17 13:08:48 -05:00
Trond Myklebust b09b9417d0 NFS: Fix the ustat() regression
Since 2.6.18, the superblock sb->s_root has been a dummy dentry with a
dummy inode. This breaks ustat(), which actually uses sb->s_root in a
vfstat() call.

Fix this by making the s_root a dummy alias to the directory inode that was
used when creating the superblock.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-17 13:08:44 -05:00