16c00db4bb
Pull AFS fixes from David Howells:
"Here's a set of patches that fix a number of bugs in the in-kernel AFS
client, including:
- Fix directory locking to not use individual page locks for
directory reading/scanning but rather to use a semaphore on the
afs_vnode struct as the directory contents must be read in a single
blob and data from different reads must not be mixed as the entire
contents may be shuffled about between reads.
- Fix address list parsing to handle port specifiers correctly.
- Only give up callback records on a server if we actually talked to
that server (we might not be able to access a server).
- Fix some callback handling bugs, including refcounting,
whole-volume callbacks and when callbacks actually get broken in
response to a CB.CallBack op.
- Fix some server/address rotation bugs, including giving up if we
can't probe a server; giving up if a server says it doesn't have a
volume, but there are more servers to try.
- Fix the decoding of fetched statuses to be OpenAFS compatible.
- Fix the handling of server lookups in Cache Manager ops (such as
CB.InitCallBackState3) to use a UUID if possible and to handle no
server being found.
- Fix a bug in server lookup where not all addresses are compared.
- Fix the non-encryption of calls that prevents some servers from
being accessed (this also requires an AF_RXRPC patch that has
already gone in through the net tree).
There's also a patch that adds tracepoints to log Cache Manager ops
that don't find a matching server, either by UUID or by address"
* tag 'afs-fixes-20180514' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Fix the non-encryption of calls
afs: Fix CB.CallBack handling
afs: Fix whole-volume callback handling
afs: Fix afs_find_server search loop
afs: Fix the handling of an unfound server in CM operations
afs: Add a tracepoint to record callbacks from unlisted servers
afs: Fix the handling of CB.InitCallBackState3 to find the server by UUID
afs: Fix VNOVOL handling in address rotation
afs: Fix AFSFetchStatus decoder to provide OpenAFS compatibility
afs: Fix server rotation's handling of fileserver probe failure
afs: Fix refcounting in callback registration
afs: Fix giving up callbacks on server destruction
afs: Fix address list parsing
afs: Fix directory page locking
96 lines
2 KiB
C
96 lines
2 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __TRIGGER_H_
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#define __TRIGGER_H_ 1
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#include "util/debug.h"
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#include "asm/bug.h"
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/*
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* Use trigger to model operations which need to be executed when
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* an event (a signal, for example) is observed.
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*
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* States and transits:
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*
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*
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* OFF--> ON --> READY --(hit)--> HIT
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* ^ |
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* | (ready)
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* | |
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* \_____________/
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*
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* is_hit and is_ready are two key functions to query the state of
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* a trigger. is_hit means the event already happen; is_ready means the
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* trigger is waiting for the event.
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*/
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struct trigger {
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volatile enum {
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TRIGGER_ERROR = -2,
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TRIGGER_OFF = -1,
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TRIGGER_ON = 0,
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TRIGGER_READY = 1,
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TRIGGER_HIT = 2,
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} state;
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const char *name;
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};
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#define TRIGGER_WARN_ONCE(t, exp) \
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WARN_ONCE(t->state != exp, "trigger '%s' state transist error: %d in %s()\n", \
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t->name, t->state, __func__)
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static inline bool trigger_is_available(struct trigger *t)
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{
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return t->state >= 0;
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}
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static inline bool trigger_is_error(struct trigger *t)
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{
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return t->state <= TRIGGER_ERROR;
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}
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static inline void trigger_on(struct trigger *t)
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{
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TRIGGER_WARN_ONCE(t, TRIGGER_OFF);
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t->state = TRIGGER_ON;
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}
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static inline void trigger_ready(struct trigger *t)
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{
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if (!trigger_is_available(t))
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return;
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t->state = TRIGGER_READY;
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}
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static inline void trigger_hit(struct trigger *t)
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{
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if (!trigger_is_available(t))
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return;
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TRIGGER_WARN_ONCE(t, TRIGGER_READY);
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t->state = TRIGGER_HIT;
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}
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static inline void trigger_off(struct trigger *t)
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{
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if (!trigger_is_available(t))
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return;
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t->state = TRIGGER_OFF;
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}
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static inline void trigger_error(struct trigger *t)
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{
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t->state = TRIGGER_ERROR;
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}
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static inline bool trigger_is_ready(struct trigger *t)
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{
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return t->state == TRIGGER_READY;
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}
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static inline bool trigger_is_hit(struct trigger *t)
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{
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return t->state == TRIGGER_HIT;
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}
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#define DEFINE_TRIGGER(n) \
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struct trigger n = {.state = TRIGGER_OFF, .name = #n}
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#endif
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