Define FS locations structures, some functions to manipulate them, and add
code to parse FS locations in downcall and add to the exports structure.

[bfields@fieldses.org: bunch of fixes and cleanups]
Signed-off-by: NManoj Naik <manoj@almaden.ibm.com>
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Store the export path in the svc_export structure instead of storing only the
dentry.  This will prevent the need for additional d_path calls to provide
NFSv4 fs_locations support.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

There is a possible race in d_splice_alias.  Though __d_find_alias(inode, 1)
will only return a dentry with DCACHE_DISCONNECTED set, it is possible for it
to get cleared before the BUG_ON, and it is is not possible to lock against
that.

There are a couple of problems here.  Firstly, the code doesn't match the
comment.  The comment describes a 'disconnected' dentry as being IS_ROOT as
well as DCACHE_DISCONNECTED, however there is not testing of IS_ROOT anythere.

A dentry is marked DCACHE_DISCONNECTED when allocated with d_alloc_anon, and
remains DCACHE_DISCONNECTED while a path is built up towards the root.  So a
dentry can have a valid name and a valid parent and even grandparent, but will
still be DCACHE_DISCONNECTED until a path to the root is created.  Once the
path to the root is complete, everything in the path gets DCACHE_DISCONNECTED
cleared.  So the fact that DCACHE_DISCONNECTED isn't enough to say that a
dentry is free to be spliced in with a given name.  This can only be allowed
if the dentry does not yet have a name, so the IS_ROOT test is needed too.

However even adding that test to __d_find_alias isn't enough.  As
d_splice_alias drops dcache_lock before calling d_move to perform the splice,
it could race with another thread calling d_splice_alias to splice the inode
in with a different name in a different part of the tree (in the case where a
file has hard links).  So that splicing code is only really safe for
directories (as we know that directories only have one link).  For
directories, the caller of d_splice_alias will be holding i_mutex on the
(unique) parent so there is no room for a race.

A consequence of this is that a non-directory will never benefit from being
spliced into a pre-exisiting dentry, but that isn't a problem.  It is
perfectly OK for a non-directory to have multiple dentries, some anonymous,
some not.  And the comment for d_splice_alias says that it only happens for
directories anyway.
Signed-off-by: NNeil Brown <neilb@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

totalram is measured in pages, not bytes, so PAGE_SHIFT must be used when
trying to find 1/4096 of RAM.

Cc:  "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

If nlm_lookup_host finds what it is looking for it exits with an extra
reference on the matching 'nsm' structure.

So don't actually count the reference until we are (fairly) sure it is going
to be used.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It is legal to have zero-length NFSv4 acls; they just deny everything.

Also, nfs4_acl_nfsv4_to_posix will always return with pacl and dpacl set on
success, so the caller doesn't need to check this.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

There's no need to handle the case where the caller passes in null for pacl or
dpacl; no caller does that, because it would be a dumb thing to do.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We can be a little more flexible about the flags allowed for inheritance (in
particular, we can deal with either the presence or the absence of
INHERIT_ONLY), but we should probably reject other combinations that we don't
understand.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use a different nfsv4->(draft posix) acl mapping which is
	1. completely backwards compatible,
	2. accepts any nfsv4 acl, and
	3. errs on the side of restricting permissions.

In detail:

	1. completely backwards compatible: The new mapping produces the
	same result on any acl produced by the existing (draft
	posix)->nfsv4 mapping; the one exception is that we no longer
	attempt to guess the value of the mask by assuming certain denies
	represent the mask.  Since the server still keeps track of the mask
	locally, sequences of chmod's will still be handled fine; the only
	thing this will change is sequences of chmod's with intervening
	read-modify-writes of the acl.  That last case just isn't worth the
	trouble and the possible misrepresentations of the user's intent
	(if we guess that a certain deny indicates masking is in effect
	when it really isn't).

	2. accepts any nfsv4 acl: That's not quite true: we still reject
	acls that use combinations of inheritance flags that we don't
	support.  We also reject acls that attempt to explicitly deny
	read_acl or read_attributes permissions, or that attempt to deny
	write_acl or write_attributes permissions to the owner of the file.

	3.  errs on the side of restricting permissions: one exception to
	this last rule: we totally ignore some bits (write_owner,
	synchronize, read_named_attributes, etc.) that are completely alien
	to our filesystem semantics, in some cases even if that would mean
	ignoring an explicit deny that we have no intention of enforcing.
	Excepting that, the posix acl produced should be the most
	permissive acl that is not more permissive than the given nfsv4
	acl.

And the new code's shorter, too.  Neato.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The previous patch enables some minor simplification here.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We could be using more common code in exp_pseudoroot().  This will also
simplify some changes we need to make later.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The rpc reply has multiple levels of error returns.  The code here contributes
to the confusion by using "accept_statp" for a pointer to what the rfc (and
wireshark, etc.) refer to as the "reply_stat".  (The confusion is compounded
by the fact that the rfc also has an "accept_stat" which follows the
reply_stat in the succesful case.)
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

If the request is denied after gss_accept was called, we shouldn't try to wrap
the reply.  We were checking the accept_stat but not the reply_stat.

To check the reply_stat in _release, we need a pointer to before (rather than
after) the verifier, so modify body_start appropriately.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Factor out some common code from the integrity and privacy cases.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Both the (recently introduces) nsm_sema and the older f_sema are converted
over.

Cc: Olaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The NFSACL patches introduced support for multiple RPC services listening on
the same transport.  However, only the first of these services was registered
with portmapper.  This was perfectly fine for nfsacl, as you traditionally do
not want these to show up in a portmapper listing.

The patch below changes the default behavior to always register all services
listening on a given transport, but retains the old behavior for nfsacl
services.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

nlmclnt_recovery would try to force a portmap rebind by setting
host->h_nextrebind to 0.  The right thing to do here is to set it to the
current time.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Every NLM call includes the client's NSM state.  Currently, the Linux client
always reports 0 - which seems not to cause any problems, but is not what the
protocol says.

This patch exposes the kernel's internal variable to user space via a sysctl,
which can be set at system boot time by statd.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When we send a GRANTED_MSG call, we current copy the NLM cookie provided in
the original LOCK call - because in 1996, some broken clients seemed to rely
on this bug.  However, this means the cookies are not unique, so that when the
client's GRANTED_RES message comes back, we cannot simply match it based on
the cookie, but have to use the client's IP address in addition.  Which breaks
when you have a multi-homed NFS client.

The X/Open spec explicitly mentions that clients should not expect the same
cookie; so one may hope that any clients that were broken in 1996 have either
been fixed or rendered obsolete.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The way we incremented the NLM cookie in nlmclnt_next_cookie was not thread
safe.  This patch changes the counter to an atomic_t
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds the nsm_use_hostnames sysctl and module param.  If set, lockd
will use the client's name (as given in the NLM arguments) to find the NSM
handle.  This makes recovery work when the NFS peer is multi-homed, and the
reboot notification arrives from a different IP than the original lock calls.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

As a result of previous patches, the loop in nlmsvc_invalidate_all just sets
h_expires for all client/hosts to 0 (though does it in a very complicated
way).

This was possibly meant to trigger early garbage collection but half the time
'0' is in the future and so it infact delays garbage collection.

Pre-aging the 'hosts' is not really needed at this point anyway so we throw
out the loop and nlm_find_client which is no longer needed.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch moves the host destruction code out of nlm_host_gc into a function
of its own.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch makes nlm_traverse{locks,blocks,shares} and friends use a function
pointer rather than a "action" enum.

This function pointer is given two nlm_hosts (one given by the caller, the
other taken from the lock/block/share currently visited), and is free to do
with them as it wants.  If it returns a non-zero value, the lockd/block/share
is released.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This changes struct nlm_file and the nlm_files hash table to use a hlist
instead of the home-grown lists.

This allows us to remove f_hash which was only used to find the right hash
chain to delete an entry from.

It also increases the size of the nlm_files hash table from 32 to 128.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch changes the nlm_blocked list to use a list_node instead of
homegrown linked list handling.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Get rid of the home-grown singly linked lists for the nlm_host hash table.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This converts the statd upcalls to use the nsm_handle

This means that we only register each host once with statd, rather than
registering each host/vers/protocol triple.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch makes the SM_NOTIFY handling understand and use the nsm_handle.

To make it a bit clear what is happening:

    nlmclent_prepare_reclaim and nlmclnt_finish_reclaim
    get open-coded into 'reclaimer'

The result is tidied up.

Then some of that functionality is moved out into nlm_host_rebooted (which
calls nlmclnt_recovery which starts a thread which runs reclaimer).

Also host_rebooted now finds an nsm_handle rather than a host, then then
iterates over all hosts and deals with each host that shares that nsm_handle.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

cleans up some code in lockd/host.c, fixes an error printk and makes it a
fatal BUG if nlmsvc_free_host_resources fails.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch introduces the nsm_handle, which is shared by all nlm_host objects
referring to the same client.

With this patch applied, all nlm_hosts from the same address will share the
same nsm_handle.  A future patch will add sharing by name.

Note: this patch changes h_name so that it is no longer guaranteed to be an IP
address of the host.  When the host represents an NFS server, h_name will be
the name passed in the mount call.  When the host represents a client, h_name
will be the name presented in the lock request received from the client.  A
h_name is only used for printing informational messages, this change should
not be significant.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds the peer's hostname (and name length) to all calls to
nlm*_lookup_host functions.  A subsequent patch will make use of these (is
requested by a sysctl).
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Common code from nlm4svc_proc_sm_notify and nlmsvc_proc_sm_notify is moved
into a new nlm_host_rebooted.

This is in preparation of a patch that will change the reboot notification
handling entirely.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch moves all checks of the h_monitored flag into the
nsm_monitor/unmonitor functions.  A subsequent patch will replace the
mechanism by which we mark a host as being monitored.

There is still one occurence of h_monitored outside of mon.c and that is in
clntlock.c where we respond to a reboot.  The subsequent patch will modify
this too.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Speed up high call-rate workloads by caching the struct ip_map for the peer on
the connected struct svc_sock instead of looking it up in the ip_map cache
hashtable on every call.  This helps workloads using AUTH_SYS authentication
over TCP.

Testing was on a 4 CPU 4 NIC Altix using 4 IRIX clients, each with 16
synthetic client threads simulating an rsync (i.e.  recursive directory
listing) workload reading from an i386 RH9 install image (161480 regular files
in 10841 directories) on the server.  That tree is small enough to fill in the
server's RAM so no disk traffic was involved.  This setup gives a sustained
call rate in excess of 60000 calls/sec before being CPU-bound on the server.

Profiling showed strcmp(), called from ip_map_match(), was taking 4.8% of each
CPU, and ip_map_lookup() was taking 2.9%.  This patch drops both contribution
into the profile noise.

Note that the above result overstates this value of this patch for most
workloads.  The synthetic clients are all using separate IP addresses, so
there are 64 entries in the ip_map cache hash.  Because the kernel measured
contained the bug fixed in commit

commit 1f1e030b

and was running on 64bit little-endian machine, probably all of those 64
entries were on a single chain, thus increasing the cost of ip_map_lookup().

With a modern kernel you would need more clients to see the same amount of
performance improvement.  This patch has helped to scale knfsd to handle a
deployment with 2000 NFS clients.
Signed-off-by: NGreg Banks <gnb@melbourne.sgi.com>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make the nfsd read-ahead params cache more SMP-friendly by changing the single
global list and lock into a fixed 16-bucket hashtable with per-bucket locks.
This reduces spinlock contention in nfsd_read() on read-heavy workloads on
multiprocessor servers.

Testing was on a 4 CPU 4 NIC Altix using 4 IRIX clients each doing 1K
streaming reads at full line rate.  The server had 128 nfsd threads, which
sizes the RA cache at 256 entries, of which only a handful were used.  Flat
profiling shows nfsd_read(), including the inlined nfsd_get_raparms(), taking
10.4% of each CPU.  This patch drops the contribution from nfsd() to 1.71% for
each CPU.
Signed-off-by: NGreg Banks <gnb@melbourne.sgi.com>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The max possible is the maximum RPC payload.  The default depends on amount of
total memory.

The value can be set within reason as long as no nfsd threads are currently
running.  The value can also be ready, allowing the default to be determined
after nfsd has started.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The limit over UDP remains at 32K.  Also, make some of the apparently
arbitrary sizing constants clearer.

The biggest change here involves replacing NFSSVC_MAXBLKSIZE by a function of
the rqstp.  This allows it to be different for different protocols (udp/tcp)
and also allows it to depend on the servers declared sv_bufsiz.

Note that we don't actually increase sv_bufsz for nfs yet.  That comes next.
Signed-off-by: NGreg Banks <gnb@melbourne.sgi.com>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

..  by allocating the array of 'kvec' in 'struct svc_rqst'.

As we plan to increase RPCSVC_MAXPAGES from 8 upto 256, we can no longer
allocate an array of this size on the stack.  So we allocate it in 'struct
svc_rqst'.

However svc_rqst contains (indirectly) an array of the same type and size
(actually several, but they are in a union).  So rather than waste space, we
move those arrays out of the separately allocated union and into svc_rqst to
share with the kvec moved out of svc_tcp_recvfrom (various arrays are used at
different times, so there is no conflict).
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We are planning to increase RPCSVC_MAXPAGES from about 8 to about 256.  This
means we need to be a bit careful about arrays of size RPCSVC_MAXPAGES.

struct svc_rqst contains two such arrays.  However the there are never more
that RPCSVC_MAXPAGES pages in the two arrays together, so only one array is
needed.

The two arrays are for the pages holding the request, and the pages holding
the reply.  Instead of two arrays, we can simply keep an index into where the
first reply page is.

This patch also removes a number of small inline functions that probably
server to obscure what is going on rather than clarify it, and opencode the
needed functionality.

Also remove the 'rq_restailpage' variable as it is *always* 0.  i.e.  if the
response 'xdr' structure has a non-empty tail it is always in the same pages
as the head.

 check counters are initilised and incr properly
 check for consistant usage of ++ etc
 maybe extra some inlines for common approach
 general review
Signed-off-by: NNeil Brown <neilb@suse.de>
Cc: Magnus Maatta <novell@kiruna.se>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>