If nfsd has existing listening sockets without any processes, then an error
returned from svc_create_xprt() for an additional transport will remove
those existing listeners.  We're seeing this in practice when userspace
attempts to create rpcrdma transports without having the rpcrdma modules
present before creating nfsd kernel processes.  Fix this by checking for
existing sockets before calling nfsd_destroy().
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

init_nfsd() should not unregister pernet subsys if the register fails
but should instead unwind from the last successful operation which is
register_filesystem().

Unregistering a failed register_pernet_subsys() call can result in
a kernel GPF as revealed by programmatically injecting an error in
register_pernet_subsys().

Verified the fix handled failure gracefully with no lingering nfsd
entry in /proc/filesystems.  This change was introduced by the commit
bd5ae928 ("nfsd: register pernet ops last, unregister first"),
the original error handling logic was correct.

Fixes: bd5ae928 ("nfsd: register pernet ops last, unregister first")
Cc: stable@vger.kernel.org
Signed-off-by: NPatrick Ho <Patrick.Ho@netapp.com>
Acked-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple
warnings by explicitly adding a couple of break statements instead of
just letting the code fall through to the next case.

Link: https://github.com/KSPP/linux/issues/115Signed-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

mountd can now monitor clients appearing and disappearing in
/proc/fs/nfsd/clients, and will log these events, in liu of the logging
of mount/unmount events for NFSv3.

Currently it cannot distinguish between unconfirmed clients (which might
be transient and totally uninteresting) and confirmed clients.

So add a "status: " line which reports either "confirmed" or
"unconfirmed", and use fsnotify to report that the info file
has been modified.

This requires a bit of infrastructure to keep the dentry for the "info"
file.  There is no need to take a counted reference as the dentry must
remain around until the client is removed.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

In order to ensure that knfsd threads don't linger once the nfsd
pseudofs is unmounted (e.g. when the container is killed) we let
nfsd_umount() shut down those threads and wait for them to exit.

This also should ensure that we don't need to do a kernel mount of
the pseudofs, since the thread lifetime is now limited by the
lifetime of the filesystem.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

These pernet operations may depend on stuff set up or torn down in the
module init/exit functions.  And they may be called at any time in
between.  So it makes more sense for them to be the last to be
registered in the init function, and the first to be unregistered in the
exit function.

In particular, without this, the drc slab is being destroyed before all
the per-net drcs are shut down, resulting in an "Objects remaining in
nfsd_drc on __kmem_cache_shutdown()" warning in exit_nfsd.
Reported-by: NZhi Li <yieli@redhat.com>
Fixes: 3ba75830 "nfsd4: drc containerization"
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

Collect some nfsd stats per export in addition to the global stats.

A new nfsdfs export_stats file is created.  It uses the same ops as the
exports file to iterate the export entries and we use the file's name to
determine the reported info per export.  For example:

 $ cat /proc/fs/nfsd/export_stats
 # Version 1.1
 # Path Client Start-time
 #	Stats
 /test	localhost	92
	fh_stale: 0
	io_read: 9
	io_write: 1

Every export entry reports the start time when stats collection
started, so stats collecting scripts can know if stats where reset
between samples.
Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

nfsd stats counters can be updated by concurrent nfsd threads without any
protection.

Convert some nfsd_stats and nfsd_net struct members to use percpu counters.

The longest_chain* members of struct nfsd_net remain unprotected.
Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

It was an interesting idea but nobody seems to be using it, it's buggy
at this point, and nfs4state.c is already complicated enough without it.
The new nfsd/clients/ code provides some of the same functionality, and
could probably do more if desired.

This feature has been deprecated since 9d60d931 ("Deprecate nfsd
fault injection").
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: NKees Cook <keescook@chromium.org>

I don't understand this code well, but  I'm seeing a warning about a
still-referenced inode on unmount, and every other similar filesystem
does a dput() here.

Fixes: e8a79fb1 ("nfsd: add nfsd/clients directory")
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We don't drop the reference on the nfsdfs filesystem with
mntput(nn->nfsd_mnt) until nfsd_exit_net(), but that won't be called
until the nfsd module's unloaded, and we can't unload the module as long
as there's a reference on nfsdfs.  So this prevents module unloading.

Fixes: 2c830dd7 ("nfsd: persist nfsd filesystem across mounts")
Reported-and-Tested-by: Luo Xiaogang <lxgrxd@163.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

I made every global per-network-namespace instead.  But perhaps doing
that to this slab was a step too far.

The kmem_cache_create call in our net init method also seems to be
responsible for this lockdep warning:

[   45.163710] Unable to find swap-space signature
[   45.375718] trinity-c1 (855): attempted to duplicate a private mapping with mremap.  This is not supported.
[   46.055744] futex_wake_op: trinity-c1 tries to shift op by -209; fix this program
[   51.011723]
[   51.013378] ======================================================
[   51.013875] WARNING: possible circular locking dependency detected
[   51.014378] 5.2.0-rc2 #1 Not tainted
[   51.014672] ------------------------------------------------------
[   51.015182] trinity-c2/886 is trying to acquire lock:
[   51.015593] 000000005405f099 (slab_mutex){+.+.}, at: slab_attr_store+0xa2/0x130
[   51.016190]
[   51.016190] but task is already holding lock:
[   51.016652] 00000000ac662005 (kn->count#43){++++}, at: kernfs_fop_write+0x286/0x500
[   51.017266]
[   51.017266] which lock already depends on the new lock.
[   51.017266]
[   51.017909]
[   51.017909] the existing dependency chain (in reverse order) is:
[   51.018497]
[   51.018497] -> #1 (kn->count#43){++++}:
[   51.018956]        __lock_acquire+0x7cf/0x1a20
[   51.019317]        lock_acquire+0x17d/0x390
[   51.019658]        __kernfs_remove+0x892/0xae0
[   51.020020]        kernfs_remove_by_name_ns+0x78/0x110
[   51.020435]        sysfs_remove_link+0x55/0xb0
[   51.020832]        sysfs_slab_add+0xc1/0x3e0
[   51.021332]        __kmem_cache_create+0x155/0x200
[   51.021720]        create_cache+0xf5/0x320
[   51.022054]        kmem_cache_create_usercopy+0x179/0x320
[   51.022486]        kmem_cache_create+0x1a/0x30
[   51.022867]        nfsd_reply_cache_init+0x278/0x560
[   51.023266]        nfsd_init_net+0x20f/0x5e0
[   51.023623]        ops_init+0xcb/0x4b0
[   51.023928]        setup_net+0x2fe/0x670
[   51.024315]        copy_net_ns+0x30a/0x3f0
[   51.024653]        create_new_namespaces+0x3c5/0x820
[   51.025257]        unshare_nsproxy_namespaces+0xd1/0x240
[   51.025881]        ksys_unshare+0x506/0x9c0
[   51.026381]        __x64_sys_unshare+0x3a/0x50
[   51.026937]        do_syscall_64+0x110/0x10b0
[   51.027509]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   51.028175]
[   51.028175] -> #0 (slab_mutex){+.+.}:
[   51.028817]        validate_chain+0x1c51/0x2cc0
[   51.029422]        __lock_acquire+0x7cf/0x1a20
[   51.029947]        lock_acquire+0x17d/0x390
[   51.030438]        __mutex_lock+0x100/0xfa0
[   51.030995]        mutex_lock_nested+0x27/0x30
[   51.031516]        slab_attr_store+0xa2/0x130
[   51.032020]        sysfs_kf_write+0x11d/0x180
[   51.032529]        kernfs_fop_write+0x32a/0x500
[   51.033056]        do_loop_readv_writev+0x21d/0x310
[   51.033627]        do_iter_write+0x2e5/0x380
[   51.034148]        vfs_writev+0x170/0x310
[   51.034616]        do_pwritev+0x13e/0x160
[   51.035100]        __x64_sys_pwritev+0xa3/0x110
[   51.035633]        do_syscall_64+0x110/0x10b0
[   51.036200]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   51.036924]
[   51.036924] other info that might help us debug this:
[   51.036924]
[   51.037876]  Possible unsafe locking scenario:
[   51.037876]
[   51.038556]        CPU0                    CPU1
[   51.039130]        ----                    ----
[   51.039676]   lock(kn->count#43);
[   51.040084]                                lock(slab_mutex);
[   51.040597]                                lock(kn->count#43);
[   51.041062]   lock(slab_mutex);
[   51.041320]
[   51.041320]  *** DEADLOCK ***
[   51.041320]
[   51.041793] 3 locks held by trinity-c2/886:
[   51.042128]  #0: 000000001f55e152 (sb_writers#5){.+.+}, at: vfs_writev+0x2b9/0x310
[   51.042739]  #1: 00000000c7d6c034 (&of->mutex){+.+.}, at: kernfs_fop_write+0x25b/0x500
[   51.043400]  #2: 00000000ac662005 (kn->count#43){++++}, at: kernfs_fop_write+0x286/0x500
Reported-by: Nkernel test robot <lkp@intel.com>
Fixes: 3ba75830 "drc containerization"
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfsctl.c:256: warning: Function parameter or member 'file' not described in 'write_unlock_ip'
fs/nfsd/nfsctl.c:256: warning: Function parameter or member 'buf' not described in 'write_unlock_ip'
fs/nfsd/nfsctl.c:256: warning: Function parameter or member 'size' not described in 'write_unlock_ip'
fs/nfsd/nfsctl.c:295: warning: Function parameter or member 'file' not described in 'write_unlock_fs'
fs/nfsd/nfsctl.c:295: warning: Function parameter or member 'buf' not described in 'write_unlock_fs'
fs/nfsd/nfsctl.c:295: warning: Function parameter or member 'size' not described in 'write_unlock_fs'
fs/nfsd/nfsctl.c:352: warning: Function parameter or member 'file' not described in 'write_filehandle'
fs/nfsd/nfsctl.c:352: warning: Function parameter or member 'buf' not described in 'write_filehandle'
fs/nfsd/nfsctl.c:352: warning: Function parameter or member 'size' not described in 'write_filehandle'
fs/nfsd/nfsctl.c:434: warning: Function parameter or member 'file' not described in 'write_threads'
fs/nfsd/nfsctl.c:434: warning: Function parameter or member 'buf' not described in 'write_threads'
fs/nfsd/nfsctl.c:434: warning: Function parameter or member 'size' not described in 'write_threads'
fs/nfsd/nfsctl.c:478: warning: Function parameter or member 'file' not described in 'write_pool_threads'
fs/nfsd/nfsctl.c:478: warning: Function parameter or member 'buf' not described in 'write_pool_threads'
fs/nfsd/nfsctl.c:478: warning: Function parameter or member 'size' not described in 'write_pool_threads'
fs/nfsd/nfsctl.c:697: warning: Function parameter or member 'file' not described in 'write_versions'
fs/nfsd/nfsctl.c:697: warning: Function parameter or member 'buf' not described in 'write_versions'
fs/nfsd/nfsctl.c:697: warning: Function parameter or member 'size' not described in 'write_versions'
fs/nfsd/nfsctl.c:858: warning: Function parameter or member 'file' not described in 'write_ports'
fs/nfsd/nfsctl.c:858: warning: Function parameter or member 'buf' not described in 'write_ports'
fs/nfsd/nfsctl.c:858: warning: Function parameter or member 'size' not described in 'write_ports'
fs/nfsd/nfsctl.c:892: warning: Function parameter or member 'file' not described in 'write_maxblksize'
fs/nfsd/nfsctl.c:892: warning: Function parameter or member 'buf' not described in 'write_maxblksize'
fs/nfsd/nfsctl.c:892: warning: Function parameter or member 'size' not described in 'write_maxblksize'
fs/nfsd/nfsctl.c:941: warning: Function parameter or member 'file' not described in 'write_maxconn'
fs/nfsd/nfsctl.c:941: warning: Function parameter or member 'buf' not described in 'write_maxconn'
fs/nfsd/nfsctl.c:941: warning: Function parameter or member 'size' not described in 'write_maxconn'
fs/nfsd/nfsctl.c:1023: warning: Function parameter or member 'file' not described in 'write_leasetime'
fs/nfsd/nfsctl.c:1023: warning: Function parameter or member 'buf' not described in 'write_leasetime'
fs/nfsd/nfsctl.c:1023: warning: Function parameter or member 'size' not described in 'write_leasetime'
fs/nfsd/nfsctl.c:1039: warning: Function parameter or member 'file' not described in 'write_gracetime'
fs/nfsd/nfsctl.c:1039: warning: Function parameter or member 'buf' not described in 'write_gracetime'
fs/nfsd/nfsctl.c:1039: warning: Function parameter or member 'size' not described in 'write_gracetime'
fs/nfsd/nfsctl.c:1094: warning: Function parameter or member 'file' not described in 'write_recoverydir'
fs/nfsd/nfsctl.c:1094: warning: Function parameter or member 'buf' not described in 'write_recoverydir'
fs/nfsd/nfsctl.c:1094: warning: Function parameter or member 'size' not described in 'write_recoverydir'
fs/nfsd/nfsctl.c:1125: warning: Function parameter or member 'file' not described in 'write_v4_end_grace'
fs/nfsd/nfsctl.c:1125: warning: Function parameter or member 'buf' not described in 'write_v4_end_grace'
fs/nfsd/nfsctl.c:1125: warning: Function parameter or member 'size' not described in 'write_v4_end_grace'

fs/nfsd/nfs4proc.c:1164: warning: Function parameter or member 'nss' not described in 'nfsd4_interssc_connect'
fs/nfsd/nfs4proc.c:1164: warning: Function parameter or member 'rqstp' not described in 'nfsd4_interssc_connect'
fs/nfsd/nfs4proc.c:1164: warning: Function parameter or member 'mount' not described in 'nfsd4_interssc_connect'
fs/nfsd/nfs4proc.c:1262: warning: Function parameter or member 'rqstp' not described in 'nfsd4_setup_inter_ssc'
fs/nfsd/nfs4proc.c:1262: warning: Function parameter or member 'cstate' not described in 'nfsd4_setup_inter_ssc'
fs/nfsd/nfs4proc.c:1262: warning: Function parameter or member 'copy' not described in 'nfsd4_setup_inter_ssc'
fs/nfsd/nfs4proc.c:1262: warning: Function parameter or member 'mount' not described in 'nfsd4_setup_inter_ssc'
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

Userspace should be able to monitor nfsd/clients/ to see when clients
come and go, but we're failing to send fsnotify events.

Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A couple of time_t variables are only used to track the state of the
lease time and its expiration. The code correctly uses the 'time_after()'
macro to make this work on 32-bit architectures even beyond year 2038,
but the get_seconds() function and the time_t type itself are deprecated
as they behave inconsistently between 32-bit and 64-bit architectures
and often lead to code that is not y2038 safe.

As a minor issue, using get_seconds() leads to problems with concurrent
settimeofday() or clock_settime() calls, in the worst case timeout never
triggering after the time has been set backwards.

Change nfsd to use time64_t and ktime_get_boottime_seconds() here. This
is clearly excessive, as boottime by itself means we never go beyond 32
bits, but it does mean we handle this correctly and consistently without
having to worry about corner cases and should be no more expensive than
the previous implementation on 64-bit architectures.

The max_cb_time() function gets changed in order to avoid an expensive
64-bit division operation, but as the lease time is at most one hour,
there is no change in behavior.

Also do the same for server-to-server copy expiration time.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
[bfields@redhat.com: fix up copy expiration]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Add support to allow the server to reset the boot verifier in order to
force clients to resend I/O after a timeout failure.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NLance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

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

A process could race in an open and attempt to read one of these files
before i_private is initialized, and get a spurious error.
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

synchronize_rcu() gets called multiple times each time a client is
destroyed.  If the laundromat thread has a lot of clients to destroy,
the delay can be noticeable.  This was causing pynfs test RENEW3 to
fail.

We could embed an rcu_head in each inode and do the kref_put in an rcu
callback.  But simplest is just to take a lock here.

(I also wonder if the laundromat thread would be better replaced by a
bunch of scheduled work or timers or something.)
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

syzbot is reporting that nfsd_mkdir() forgot to remove dentry created by
d_alloc_name() when __nfsd_mkdir() failed (due to memory allocation fault
injection) [1].

[1] https://syzkaller.appspot.com/bug?id=ce41a1f769ea4637ebffedf004a803e8405b4674Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: Nsyzbot <syzbot+2c95195d5d433f6ed6cb@syzkaller.appspotmail.com>
Fixes: e8a79fb1 ("nfsd: add nfsd/clients directory")
[bfields: clean up in nfsd_mkdir instead of __nfsd_mkdir]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Fix sparse warning:

fs/nfsd/nfsctl.c:1221:22: warning:
 symbol '__get_nfsdfs_client' was not declared. Should it be static?
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Add a new nfsd/clients/#/info file with some basic information about
each NFSv4 client.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We want clientid's on the wire to be randomized for reasons explained in
ebd7c72c "nfsd: randomize SETCLIENTID reply to help distinguish
servers".  But I'd rather have mostly small integers for the clients/
directory.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

I plan to expose some information about nfsv4 clients here.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Keep around one internal mount of the nfsd filesystem so that we can add
stuff to it when clients come and go, regardless of whether anyone has
it mounted.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The nfsd duplicate reply cache should not be shared between network
namespaces.

The most straightforward way to fix this is just to move every global in
the code to per-net-namespace memory, so that's what we do.

Still todo: sort out which members of nfsd_stats should be global and
which per-net-namespace.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190612152603.GB18440@kroah.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Convert the nfsctl filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: "J. Bruce Fields" <bfields@fieldses.org>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-nfs@vger.kernel.org

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In order to be able to interpret uids and gids correctly in knfsd, we
should cache the user namespace of the process that created the RPC
server's listener. To do so, we refcount the credential of that process.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Support use of the --nfs-version/--no-nfs-version arguments to rpc.nfsd
in containers.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

When using nfsdcld for NFSv4 client tracking, track the number of
RECLAIM_COMPLETE operations we receive from "known" clients to help in
deciding if we can lift the grace period early (or whether we need to
start a v4 grace period at all).
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Commit 62a063b8 "nfsd4: fix crash on writing v4_end_grace before
nfsd startup" is trying to fix a NULL dereference issue, but it
mistakenly checks if the nfsd server is started. So fix it.

Fixes: 62a063b8 "nfsd4: fix crash on writing v4_end_grace before nfsd startup"
Cc: stable@vger.kernel.org
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: NYihao Wu <wuyihao@linux.alibaba.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This reverts commit d6ebf508.

I forgot that the kernel's default lease period should never be
decreased!

After a kernel upgrade, the kernel has no way of knowing on its own what
the previous lease time was.  Unless userspace tells it otherwise, it
will assume the previous lease period was the same.

So if we decrease this value in a kernel upgrade, we end up enforcing a
grace period that's too short, and clients will fail to reclaim state in
time.  Symptoms may include EIO and log messages like "NFS:
nfs4_reclaim_open_state: Lock reclaim failed!"

There was no real justification for the lease period decrease anyway.
Reported-by: NDonald Buczek <buczek@molgen.mpg.de>
Fixes: d6ebf508 "nfsd4: return default lease period"
Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Anatoly Trosinenko reports that this:

1) Checkout fresh master Linux branch (tested with commit e195ca6c)
2) Copy x84_64-config-4.14 to .config, then enable NFS server v4 and build
3) From `kvm-xfstests shell`:

results in NULL dereference in locks_end_grace.

Check that nfsd has been started before trying to end the grace period.
Reported-by: NAnatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Upon receiving a request for async copy, create a new kthread.  If we
get asynchronous request, make sure to copy the needed arguments/state
from the stack before starting the copy. Then start the thread and reply
back to the client indicating copy is asynchronous.

nfsd_copy_file_range() will copy in a loop over the total number of
bytes is needed to copy. In case a failure happens in the middle, we
ignore the error and return how much we copied so far. Once done
creating a workitem for the callback workqueue and send CB_OFFLOAD with
the results.

The lifetime of the copy stateid is bound to the vfs copy. This way we
don't need to keep the nfsd_net structure for the callback.  We could
keep it around longer so that an OFFLOAD_STATUS that came late would
still get results, but clients should be able to deal without that.

We handle OFFLOAD_CANCEL by sending a signal to the copy thread and
calling kthread_stop.

A client should cancel any ongoing copies before calling DESTROY_CLIENT;
if not, we return a CLIENT_BUSY error.

If the client is destroyed for some other reason (lease expiration, or
server shutdown), we must clean up any ongoing copies ourselves.
Signed-off-by: NOlga Kornievskaia <kolga@netapp.com>
[colin.king@canonical.com: fix leak in error case]
[bfields@fieldses.org: remove signalling, merge patches]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

write_op[] is never modified, so make it 'const'.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

I don't have a good rationale for the lease period, but 90 seconds seems
long, and as long as we're allowing the server to extend the grace
period up to double the lease period, let's half the default to 45.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>