timers: Get rid of del_singleshot_timer_sync()

del_singleshot_timer_sync() used to be an optimization for deleting timers
which are not rearmed from the timer callback function.

This optimization t

timers: Get rid of del_singleshot_timer_sync()

del_singleshot_timer_sync() used to be an optimization for deleting timers
which are not rearmed from the timer callback function.

This optimization turned out to be broken and got mapped to
del_timer_sync() about 17 years ago.

Get rid of the undocumented indirection and use del_timer_sync() directly.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Link: https://lore.kernel.org/r/20221123201624.706987932@linutronix.de

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treewide: use get_random_u32() when possible

The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same cod

treewide: use get_random_u32() when possible

The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. The same also applies to get_random_int(), which is
just a wrapper around get_random_u32(). This was done as a basic find
and replace.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake
Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Acked-by: Helge Deller <deller@gmx.de> # for parisc
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

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SUNRPC: use max_t() to simplify open code

Use max_t() to simplify open code which uses "if...else" to get maximum of
two values.

Generated by coccinelle script:
scripts/coccinelle/misc/minmax.cocc

SUNRPC: use max_t() to simplify open code

Use max_t() to simplify open code which uses "if...else" to get maximum of
two values.

Generated by coccinelle script:
scripts/coccinelle/misc/minmax.cocci

Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

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SUNRPC: Directly use ida_alloc()/free()

Use ida_alloc()/ida_free() instead of
ida_simple_get()/ida_simple_remove().
The latter is deprecated and more verbose.

Signed-off-by: Bo Liu <liubo03@inspur.

SUNRPC: Directly use ida_alloc()/free()

Use ida_alloc()/ida_free() instead of
ida_simple_get()/ida_simple_remove().
The latter is deprecated and more verbose.

Signed-off-by: Bo Liu <liubo03@inspur.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

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SUNRPC: Fix call completion races with call_decode()

We need to make sure that the req->rq_private_buf is completely up to
date before we make req->rq_reply_bytes_recvd visible to the
call_decode()

SUNRPC: Fix call completion races with call_decode()

We need to make sure that the req->rq_private_buf is completely up to
date before we make req->rq_reply_bytes_recvd visible to the
call_decode() routine in order to avoid triggering the WARN_ON().

Reported-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: 72691a269f0b ("SUNRPC: Don't reuse bvec on retransmission of the request")
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: Don't reuse bvec on retransmission of the request

If a request is re-encoded and then retransmitted, we need to make sure
that we also re-encode the bvec, in case the page lists have changed

SUNRPC: Don't reuse bvec on retransmission of the request

If a request is re-encoded and then retransmitted, we need to make sure
that we also re-encode the bvec, in case the page lists have changed.

Fixes: ff053dbbaffe ("SUNRPC: Move the call to xprt_send_pagedata() out of xprt_sock_sendmsg()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC create an rpc function that allows xprt removal from rpc_clnt

Expose a function that allows a removal of xprt from the rpc_clnt.

When called from NFS that's running a trunked transport then

SUNRPC create an rpc function that allows xprt removal from rpc_clnt

Expose a function that allows a removal of xprt from the rpc_clnt.

When called from NFS that's running a trunked transport then don't
decrement the active transport counter.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC expose functions for offline remote xprt functionality

Re-arrange the code that make offline transport and delete transport
callable functions.

Signed-off-by: Olga Kornievskaia <kolga@netapp

SUNRPC expose functions for offline remote xprt functionality

Re-arrange the code that make offline transport and delete transport
callable functions.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: Ensure we flush any closed sockets before xs_xprt_free()

We must ensure that all sockets are closed before we call xprt_free()
and release the reference to the net namespace. The problem is

SUNRPC: Ensure we flush any closed sockets before xs_xprt_free()

We must ensure that all sockets are closed before we call xprt_free()
and release the reference to the net namespace. The problem is that
calling fput() will defer closing the socket until delayed_fput() gets
called.
Let's fix the situation by allowing rpciod and the transport teardown
code (which runs on the system wq) to call __fput_sync(), and directly
close the socket.

Reported-by: Felix Fu <foyjog@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Fixes: a73881c96d73 ("SUNRPC: Fix an Oops in udp_poll()")
Cc: stable@vger.kernel.org # 5.1.x: 3be232f11a3c: SUNRPC: Prevent immediate close+reconnect
Cc: stable@vger.kernel.org # 5.1.x: 89f42494f92f: SUNRPC: Don't call connect() more than once on a TCP socket
Cc: stable@vger.kernel.org # 5.1.x
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: handle malloc failure in ->request_prepare

If ->request_prepare() detects an error, it sets ->rq_task->tk_status.
This is easy for callers to ignore.
The only caller is xprt_request_enqueue_

SUNRPC: handle malloc failure in ->request_prepare

If ->request_prepare() detects an error, it sets ->rq_task->tk_status.
This is easy for callers to ignore.
The only caller is xprt_request_enqueue_receive() and it does ignore the
error, as does call_encode() which calls it. This can result in a
request being queued to receive a reply without an allocated receive buffer.

So instead of setting rq_task->tk_status, return an error, and store in
->tk_status only in call_encode();

The call to xprt_request_enqueue_receive() is now earlier in
call_encode(), where the error can still be handled.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: avoid race between mod_timer() and del_timer_sync()

xprt_destory() claims XPRT_LOCKED and then calls del_timer_sync().
Both xprt_unlock_connect() and xprt_release() call
->release_xprt()
wh

SUNRPC: avoid race between mod_timer() and del_timer_sync()

xprt_destory() claims XPRT_LOCKED and then calls del_timer_sync().
Both xprt_unlock_connect() and xprt_release() call
->release_xprt()
which drops XPRT_LOCKED and *then* xprt_schedule_autodisconnect()
which calls mod_timer().

This may result in mod_timer() being called *after* del_timer_sync().
When this happens, the timer may fire long after the xprt has been freed,
and run_timer_softirq() will probably crash.

The pairing of ->release_xprt() and xprt_schedule_autodisconnect() is
always called under ->transport_lock. So if we take ->transport_lock to
call del_timer_sync(), we can be sure that mod_timer() will run first
(if it runs at all).

Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: Make the rpciod and xprtiod slab allocation modes consistent

Make sure that rpciod and xprtiod are always using the same slab
allocation modes.

Signed-off-by: Trond Myklebust <trond.myklebu

SUNRPC: Make the rpciod and xprtiod slab allocation modes consistent

Make sure that rpciod and xprtiod are always using the same slab
allocation modes.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: improve 'swap' handling: scheduling and PF_MEMALLOC

rpc tasks can be marked as RPC_TASK_SWAPPER. This causes GFP_MEMALLOC
to be used for some allocations. This is needed in some cases, but

SUNRPC: improve 'swap' handling: scheduling and PF_MEMALLOC

rpc tasks can be marked as RPC_TASK_SWAPPER. This causes GFP_MEMALLOC
to be used for some allocations. This is needed in some cases, but not
in all where it is currently provided, and in some where it isn't
provided.

Currently *all* tasks associated with a rpc_client on which swap is
enabled get the flag and hence some GFP_MEMALLOC support.

GFP_MEMALLOC is provided for ->buf_alloc() but only swap-writes need it.
However xdr_alloc_bvec does not get GFP_MEMALLOC - though it often does
need it.

xdr_alloc_bvec is called while the XPRT_LOCK is held. If this blocks,
then it blocks all other queued tasks. So this allocation needs
GFP_MEMALLOC for *all* requests, not just writes, when the xprt is used
for any swap writes.

Similarly, if the transport is not connected, that will block all
requests including swap writes, so memory allocations should get
GFP_MEMALLOC if swap writes are possible.

So with this patch:
1/ we ONLY set RPC_TASK_SWAPPER for swap writes.
2/ __rpc_execute() sets PF_MEMALLOC while handling any task
with RPC_TASK_SWAPPER set, or when handling any task that
holds the XPRT_LOCKED lock on an xprt used for swap.
This removes the need for the RPC_IS_SWAPPER() test
in ->buf_alloc handlers.
3/ xprt_prepare_transmit() sets PF_MEMALLOC after locking
any task to a swapper xprt. __rpc_execute() will clear it.
3/ PF_MEMALLOC is set for all the connect workers.

Reviewed-by: Chuck Lever <chuck.lever@oracle.com> (for xprtrdma parts)
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: remove scheduling boost for "SWAPPER" tasks.

Currently, tasks marked as "swapper" tasks get put to the front of
non-priority rpc_queues, and are sorted earlier than non-swapper tasks on
the

SUNRPC: remove scheduling boost for "SWAPPER" tasks.

Currently, tasks marked as "swapper" tasks get put to the front of
non-priority rpc_queues, and are sorted earlier than non-swapper tasks on
the transport's ->xmit_queue.

This is pointless as currently *all* tasks for a mount that has swap
enabled on *any* file are marked as "swapper" tasks. So the net result
is that the non-priority rpc_queues are reverse-ordered (LIFO).

This scheduling boost is not necessary to avoid deadlocks, and hurts
fairness, so remove it. If there were a need to expedite some requests,
the tk_priority mechanism is a more appropriate tool.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC/xprt: async tasks mustn't block waiting for memory

When memory is short, new worker threads cannot be created and we depend
on the minimum one rpciod thread to be able to handle everything.

SUNRPC/xprt: async tasks mustn't block waiting for memory

When memory is short, new worker threads cannot be created and we depend
on the minimum one rpciod thread to be able to handle everything. So it
must not block waiting for memory.

xprt_dynamic_alloc_slot can block indefinitely. This can tie up all
workqueue threads and NFS can deadlock. So when called from a
workqueue, set __GFP_NORETRY.

The rdma alloc_slot already does not block. However it sets the error
to -EAGAIN suggesting this will trigger a sleep. It does not. As we
can see in call_reserveresult(), only -ENOMEM causes a sleep. -EAGAIN
causes immediate retry.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: Convert GFP_NOFS to GFP_KERNEL

The sections which should not re-enter the filesystem are already
protected with memalloc_nofs_save/restore calls, so it is better to use
GFP_KERNEL in these c

SUNRPC: Convert GFP_NOFS to GFP_KERNEL

The sections which should not re-enter the filesystem are already
protected with memalloc_nofs_save/restore calls, so it is better to use
GFP_KERNEL in these calls to allow better performance for synchronous
RPC calls.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: add netns refcount tracker to struct rpc_xprt

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

SUNRPC: Prevent immediate close+reconnect

If we have already set up the socket and are waiting for it to connect,
then don't immediately close and retry.

Signed-off-by: Trond Myklebust <trond.mykle

SUNRPC: Prevent immediate close+reconnect

If we have already set up the socket and are waiting for it to connect,
then don't immediately close and retry.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: Fix races when closing the socket

Ensure that we bump the xprt->connect_cookie when we set the
XPRT_CLOSE_WAIT flag so that another call to
xprt_conditional_disconnect() won't race with the

SUNRPC: Fix races when closing the socket

Ensure that we bump the xprt->connect_cookie when we set the
XPRT_CLOSE_WAIT flag so that another call to
xprt_conditional_disconnect() won't race with the reconnection.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: xprt_clear_locked() only needs release memory semantics

The clearing of the XPRT_LOCKED bit has to happen after we clear
xprt->snd_task, but we don't require any extra memory barriers after

SUNRPC: xprt_clear_locked() only needs release memory semantics

The clearing of the XPRT_LOCKED bit has to happen after we clear
xprt->snd_task, but we don't require any extra memory barriers after
that.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: Partial revert of commit 6f9f17287e78

The premise of commit 6f9f17287e78 ("SUNRPC: Mitigate cond_resched() in
xprt_transmit()") was that cond_resched() is expensive and unnecessary
when ther

SUNRPC: Partial revert of commit 6f9f17287e78

The premise of commit 6f9f17287e78 ("SUNRPC: Mitigate cond_resched() in
xprt_transmit()") was that cond_resched() is expensive and unnecessary
when there has been just a single send.
The point of cond_resched() is to ensure that tasks that should pre-empt
this one get a chance to do so when it is safe to do so. The code prior
to commit 6f9f17287e78 failed to take into account that it was keeping a
rpc_task pinned for longer than it needed to, and so rather than doing a
full revert, let's just move the cond_resched.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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SUNRPC: Ensure we flush any closed sockets before xs_xprt_free()

commit f00432063db1a0db484e85193eccc6845435b80e upstream.

We must ensure that all sockets are closed before we call xprt_free()
and

SUNRPC: Ensure we flush any closed sockets before xs_xprt_free()

commit f00432063db1a0db484e85193eccc6845435b80e upstream.

We must ensure that all sockets are closed before we call xprt_free()
and release the reference to the net namespace. The problem is that
calling fput() will defer closing the socket until delayed_fput() gets
called.
Let's fix the situation by allowing rpciod and the transport teardown
code (which runs on the system wq) to call __fput_sync(), and directly
close the socket.

Reported-by: Felix Fu <foyjog@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Fixes: a73881c96d73 ("SUNRPC: Fix an Oops in udp_poll()")
Cc: stable@vger.kernel.org # 5.1.x: 3be232f11a3c: SUNRPC: Prevent immediate close+reconnect
Cc: stable@vger.kernel.org # 5.1.x: 89f42494f92f: SUNRPC: Don't call connect() more than once on a TCP socket
Cc: stable@vger.kernel.org # 5.1.x
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Meena Shanmugam <meenashanmugam@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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SUNRPC: Prevent immediate close+reconnect

commit 3be232f11a3cc9b0ef0795e39fa11bdb8e422a06 upstream.

If we have already set up the socket and are waiting for it to connect,
then don't immediately cl

SUNRPC: Prevent immediate close+reconnect

commit 3be232f11a3cc9b0ef0795e39fa11bdb8e422a06 upstream.

If we have already set up the socket and are waiting for it to connect,
then don't immediately close and retry.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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SUNRPC: remove scheduling boost for "SWAPPER" tasks.

[ Upstream commit a80a8461868905823609be97f91776a26befe839 ]

Currently, tasks marked as "swapper" tasks get put to the front of
non-priority rpc

SUNRPC: remove scheduling boost for "SWAPPER" tasks.

[ Upstream commit a80a8461868905823609be97f91776a26befe839 ]

Currently, tasks marked as "swapper" tasks get put to the front of
non-priority rpc_queues, and are sorted earlier than non-swapper tasks on
the transport's ->xmit_queue.

This is pointless as currently *all* tasks for a mount that has swap
enabled on *any* file are marked as "swapper" tasks. So the net result
is that the non-priority rpc_queues are reverse-ordered (LIFO).

This scheduling boost is not necessary to avoid deadlocks, and hurts
fairness, so remove it. If there were a need to expedite some requests,
the tk_priority mechanism is a more appropriate tool.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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SUNRPC/xprt: async tasks mustn't block waiting for memory

[ Upstream commit a721035477fb5fb8abc738fbe410b07c12af3dc5 ]

When memory is short, new worker threads cannot be created and we depend
on th

SUNRPC/xprt: async tasks mustn't block waiting for memory

[ Upstream commit a721035477fb5fb8abc738fbe410b07c12af3dc5 ]

When memory is short, new worker threads cannot be created and we depend
on the minimum one rpciod thread to be able to handle everything. So it
must not block waiting for memory.

xprt_dynamic_alloc_slot can block indefinitely. This can tie up all
workqueue threads and NFS can deadlock. So when called from a
workqueue, set __GFP_NORETRY.

The rdma alloc_slot already does not block. However it sets the error
to -EAGAIN suggesting this will trigger a sleep. It does not. As we
can see in call_reserveresult(), only -ENOMEM causes a sleep. -EAGAIN
causes immediate retry.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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