Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.
We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.
But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.
->read_proc/->write_proc were just fixed to not require ->owner for
protection.
rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.
Removing ->owner will also make PDE smaller.
So, let's nuke it.
Kudos to Jeff Layton for reminding about this, let's say, oversight.
http://bugzilla.kernel.org/show_bug.cgi?id=12454
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Callback requests from IPv4 servers are now always guaranteed to be
AF_INET, and never mapped IPv4 AF_INET6 addresses. Both
nfs_match_client() and nfs_find_client() can now share the same
address comparison logic, so fold them together.
We can also dispense with of most of the conditional compilation
in here.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Stephen Rothwell reports:
Today's linux-next build (powerpc ppc64_defconfig) failed like this:
fs/built-in.o: In function `.nfs_get_client':
client.c:(.text+0x115010): undefined reference to `.__ipv6_addr_type'
Fix by moving the IPV6 specific parts of commit
d7371c41b0 ("Bug 11061, NFS mounts dropped")
into the '#ifdef IPV6..." section.
Also fix up a couple of formatting issues.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Addresses: http://bugzilla.kernel.org/show_bug.cgi?id=11061
sockaddr structures can't be reliably compared using memcmp() because
there are padding bytes in the structure which can't be guaranteed to
be the same even when the sockaddr structures refer to the same
socket. Instead compare all the relevant fields. In the case of IPv6
sin6_flowinfo is not compared because it only affects QoS and
sin6_scope_id is only compared if the address is "link local" because
"link local" addresses need only be unique to a specific link.
Signed-off-by: Ian Dall <ian@beware.dropbear.id.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, the callback server is listening on IPv6 if it is enabled. This
means that IPv4 addresses will always be mapped.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Now that we're using the flags to indicate state that needs to be
recovered, as well as having implemented proper refcounting and spinlocking
on the state and open_owners, we can get rid of nfs_client->cl_sem. The
only remaining case that was dubious was the file locking, and that case is
now covered by the nfsi->rwsem.
Signed-off-by: Trond 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 lockd client should use an
unprivileged port in this case as well.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond 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: Chuck 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: Trond Myklebust <Trond.Myklebust@netapp.com>
Make it possible for the NFSv4 mount set up logic to pass mount option
flags down the stack to nfs_create_rpc_client().
This is immediately useful if we want NFS mount options to modulate
settings of the underlying RPC transport, but it may be useful at some
later point if other parts of the NFSv4 mount initialization logic
want to know what the mount options are.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The nfs_create_rpc_client() function sets up an RPC client for an NFS
mount point. Add an option that allows it to set up an RPC transport
from an unprivileged port.
Instead of having nfs_create_rpc_client()'s callers retain local
knowledge about how to set up an RPC client, create a couple of flag
arguments to control the use of RPC_CLNT_CREATE flags.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond 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: Trond 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: Trond 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: Trond Myklebust <Trond.Myklebust@netapp.com>
Use proc_create() to make sure that ->proc_fops be setup before gluing PDE to
main tree.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use creation by full path instead: "fs/foo".
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need to try to ensure that we always use the same credentials whenever
we re-establish the clientid on the server. If not, the server won't
recognise that we're the same client, and so may not allow us to recover
state.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Save the value of the mountproto= mountport= mountvers= and mountaddr=
options so that these values can be displayed later via
nfs_show_options().
This preserves the intent of the original mount options, should the file
system need to be remounted based on what's displayed in /proc/mounts.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
During a remount based on the mount options displayed in /proc/mounts, we
want to preserve the original behavior of the mount request. Let's save
the original setting of the "port=" mount option in the mount's nfs_server
structure.
This allows us to simplify the default behavior of port setting for NFSv4
mounts: by default, NFSv2/3 mounts first try an RPC bind to determine the
NFS server's port, unless the user specified the "port=" mount option;
Users can force the client to skip the RPC bind by explicitly specifying
"port=<value>".
NFSv4, by contrast, assumes the NFS server port is 2049 and skips the RPC
bind, unless the user specifies "port=". Users can force an RPC bind for
NFSv4 by explicitly specifying "port=0".
I added a couple of extra comments to clarify this behavior.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits)
Remove commented-out code copied from NFS
NFS: Switch from intr mount option to TASK_KILLABLE
Add wait_for_completion_killable
Add wait_event_killable
Add schedule_timeout_killable
Use mutex_lock_killable in vfs_readdir
Add mutex_lock_killable
Use lock_page_killable
Add lock_page_killable
Add fatal_signal_pending
Add TASK_WAKEKILL
exit: Use task_is_*
signal: Use task_is_*
sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL
ptrace: Use task_is_*
power: Use task_is_*
wait: Use TASK_NORMAL
proc/base.c: Use task_is_*
proc/array.c: Use TASK_REPORT
perfmon: Use task_is_*
...
Fixed up conflicts in NFS/sunrpc manually..
The same delegation may have been handed out to more than one nfs_client.
Ensure that if a recall occurs, we return all instances.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: pass 5 arguments to nlmclnt_init() in a structure similar to the
new nfs_client_initdata structure.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cache an appropriate nlm_host structure in the NFS client's mount point
metadata for later use.
Note that there is no need to set NFS_MOUNT_NONLM in the error case -- if
nfs_start_lockd() returns a non-zero value, its callers ensure that the
mount request fails outright.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, if you have a server mounted using networking protocol, you
cannot specify a different value using the 'proto=' option on another
mountpoint.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace the nfs_server and mount_server address fields in the
nfs_parsed_mount_data structure with a "struct sockaddr_storage"
instead of a "struct sockaddr_in".
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>
Change the addr field in the nfs_clone_mount structure to store a "struct
sockaddr *" to support non-IPv4 addresses in the NFS client.
Note this is mostly a cosmetic change, and does not actually allow
referrals using IPv6 addresses. The existing referral code assumes that
the server returns a string that represents an IPv4 address. This code
needs to support hostnames and IPv6 addresses as well as IPv4 addresses,
thus it will need to be reorganized completely (to handle DNS resolution
in user space).
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>
Adjust the arguments and callers of nfs4_set_client() to pass a "struct
sockaddr *" instead of a "struct sockaddr_in *" to support non-IPv4
addresses in the NFS client.
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>
Adjust arguments and callers of nfs_get_client() to pass a
"struct sockaddr *" instead of "struct sockaddr_in *" to support
non-IPv4 addresses.
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>
Adjust arguments and callers of nfs_find_client() to pass a
"struct sockaddr *" instead of "struct sockaddr_in *" to support non-IPv4
addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Trond: Also fix up protocol version number argument in nfs_find_client() to
use the correct u32 type.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Prepare for managing larger addresses in the NFS client by widening the
nfs_client struct's cl_addr field.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
(Modified to work with the new parameters for nfs_alloc_client)
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
To ensure the NFS client displays IPv6 addresses properly, replace
address family-specific NIPQUAD() invocations with a call to the RPC
client to get a formatted string representing the remote peer's
address.
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>
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>
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>
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>
By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr'
mount option. We have to use _killable everywhere instead of _interruptible
as we get rid of rpc_clnt_sigmask/sigunmask.
Signed-off-by: Liam R. Howlett <howlett@gmail.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
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>
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>
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>
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>
It doesn't look as if the NFS file name limit is being initialised correctly
in the struct nfs_server. Make sure that we limit whatever is being set in
nfs_probe_fsinfo() and nfs_init_server().
Also ensure that readdirplus and nfs4_path_walk respect our file name
limits.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This includes /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes entries.
Both need to show the header and use the list_head.
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: 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>