Murali Nalajala c36ece177e vservices: core: Port core vservices drivers to linux 4.14
Vservices core drivers are broken on 4.14 kernel due to core
framework changes.This commit updates the virtual services
core to build and run on linux 4.14.

Change-Id: I53360a8b8431d58c4569d4d4c3b86f3c820b6faf
Signed-off-by: Murali Nalajala <mnalajal@codeaurora.org>
2018-11-19 18:17:34 -08:00

455 lines
18 KiB
C

/*
* include/vservices/wait.h
*
* Copyright (c) 2012-2018 General Dynamics
* Copyright (c) 2014 Open Kernel Labs, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Generic wait event helpers for Virtual Service drivers.
*/
#ifndef _VSERVICE_SERVICE_WAIT_H
#define _VSERVICE_SERVICE_WAIT_H
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/sched/signal.h>
/* Older kernels don't have lockdep_assert_held_once(). */
#ifndef lockdep_assert_held_once
#ifdef CONFIG_LOCKDEP
#define lockdep_assert_held_once(l) do { \
WARN_ON_ONCE(debug_locks && !lockdep_is_held(l)); \
} while (0)
#else
#define lockdep_assert_held_once(l) do { } while (0)
#endif
#endif
/* Legacy wait macro; needs rewriting to use vs_state_lock_safe(). */
/* FIXME: Redmine ticket #229 - philip. */
/**
* __vs_service_wait_event - Wait for a condition to become true for a
* Virtual Service.
*
* @_service: The service to wait for the condition to be true for.
* @_wq: Waitqueue to wait on.
* @_condition: Condition to wait for.
*
* Returns: This function returns 0 if the condition is true, or a -ERESTARTSYS
* if the wait loop wait interrupted. If _state is TASK_UNINTERRUPTIBLE
* then this function will always return 0.
*
* This function must be called with the service's state lock held. The wait
* is performed without the state lock held, but the condition is re-checked
* after reacquiring the state lock. This property allows this function to
* check the state of the service's protocol in a thread safe manner.
*
* The caller is responsible for ensuring that it has not been detached from
* the given service.
*
* It is nearly always wrong to call this on the service workqueue, since
* the workqueue is single-threaded and the state can only change when a
* handler function is called on it.
*/
#define __vs_service_wait_event(_service, _wq, _cond, _state) \
({ \
DEFINE_WAIT(__wait); \
int __ret = 0; \
\
lockdep_assert_held_once(&(_service)->state_mutex); \
do { \
prepare_to_wait(&(_wq), &__wait, (_state)); \
\
if (_cond) \
break; \
\
if ((_state) == TASK_INTERRUPTIBLE && \
signal_pending(current)) { \
__ret = -ERESTARTSYS; \
break; \
} \
\
vs_service_state_unlock(_service); \
schedule(); \
vs_service_state_lock(_service); \
} while (!(_cond)); \
\
finish_wait(&(_wq), &__wait); \
__ret; \
})
/* Legacy wait macros; need rewriting to use __vs_wait_state(). */
/* FIXME: Redmine ticket #229 - philip. */
#define vs_service_wait_event(_service, _wq, _cond) \
__vs_service_wait_event(_service, _wq, _cond, TASK_INTERRUPTIBLE)
#define vs_service_wait_event_nointr(_service, _wq, _cond) \
__vs_service_wait_event(_service, _wq, _cond, TASK_UNINTERRUPTIBLE)
/**
* __vs_wait_state - block until a condition becomes true on a service state.
*
* @_state: The protocol state to wait on.
* @_cond: Condition to wait for.
* @_intr: If true, perform an interruptible wait; the wait may then fail
* with -ERESTARTSYS.
* @_timeout: A timeout in jiffies, or negative for no timeout. If the
* timeout expires, the wait will fail with -ETIMEDOUT.
* @_bh: The token _bh if this service uses tx_atomic (sends from a
* non-framework tasklet); otherwise nothing.
*
* Return: Return a pointer to a message buffer on successful allocation,
* or an error code in ERR_PTR form.
*
* This macro blocks waiting until a particular condition becomes true on a
* service state. The service must be running; if not, or if it ceases to be
* running during the wait, -ECANCELED will be returned.
*
* This is not an exclusive wait. If an exclusive wait is desired it is
* usually better to use the waiting alloc or send functions.
*
* This macro must be called with a reference to the service held, and with
* the service's state lock held. The state lock will be dropped by waiting
* but reacquired before returning, unless -ENOLINK is returned, in which case
* the service driver has been unbound and the lock cannot be reacquired.
*/
#define __vs_wait_state(_state, _cond, _intr, _timeout, _bh) \
({ \
DEFINE_WAIT(__wait); \
int __ret; \
int __jiffies __maybe_unused = (_timeout); \
struct vs_service_device *__service = (_state)->service;\
\
while (1) { \
prepare_to_wait(&__service->quota_wq, &__wait, \
_intr ? TASK_INTERRUPTIBLE : \
TASK_UNINTERRUPTIBLE); \
\
if (!VSERVICE_BASE_STATE_IS_RUNNING( \
(_state)->state.base)) { \
__ret = -ECANCELED; \
break; \
} \
\
if (_cond) { \
__ret = 0; \
break; \
} \
\
if (_intr && signal_pending(current)) { \
__ret = -ERESTARTSYS; \
break; \
} \
\
vs_state_unlock##_bh(_state); \
\
if (_timeout >= 0) { \
__jiffies = schedule_timeout(__jiffies);\
if (!__jiffies) { \
__ret = -ETIMEDOUT; \
break; \
} \
} else { \
schedule(); \
} \
\
if (!vs_state_lock_safe##_bh(_state)) { \
__ret = -ENOLINK; \
break; \
} \
} \
\
finish_wait(&__service->quota_wq, &__wait); \
__ret; \
})
/* Specialisations of __vs_wait_state for common uses. */
#define vs_wait_state(_state, _cond) \
__vs_wait_state(_state, _cond, true, -1,)
#define vs_wait_state_timeout(_state, _cond, _timeout) \
__vs_wait_state(_state, _cond, true, _timeout,)
#define vs_wait_state_nointr(_state, _cond) \
__vs_wait_state(_state, _cond, false, -1,)
#define vs_wait_state_nointr_timeout(_state, _cond, _timeout) \
__vs_wait_state(_state, _cond, false, _timeout,)
#define vs_wait_state_bh(_state, _cond) \
__vs_wait_state(_state, _cond, true, -1, _bh)
#define vs_wait_state_timeout_bh(_state, _cond, _timeout) \
__vs_wait_state(_state, _cond, true, _timeout, _bh)
#define vs_wait_state_nointr_bh(_state, _cond) \
__vs_wait_state(_state, _cond, false, -1, _bh)
#define vs_wait_state_nointr_timeout_bh(_state, _cond, _timeout) \
__vs_wait_state(_state, _cond, false, _timeout, _bh)
/**
* __vs_wait_alloc - block until quota is available, then allocate a buffer.
*
* @_state: The protocol state to allocate a message for.
* @_alloc_func: The message buffer allocation function to run. This is the
* full function invocation, not a pointer to the function.
* @_cond: Additional condition which must remain true, or else the wait
* will fail with -ECANCELED. This is typically used to check the
* service's protocol state. Note that this condition will only
* be checked after sleeping; it is assumed to be true when the
* macro is first called.
* @_unlock: If true, drop the service state lock before sleeping. The wait
* may then fail with -ENOLINK if the driver is detached from the
* service, in which case the lock is dropped.
* @_intr: If true, perform an interruptible wait; the wait may then fail
* with -ERESTARTSYS.
* @_timeout: A timeout in jiffies, or negative for no timeout. If the
* timeout expires, the wait will fail with -ETIMEDOUT.
* @_bh: The token _bh if this service uses tx_atomic (sends from a
* non-framework tasklet); otherwise nothing.
*
* Return: Return a pointer to a message buffer on successful allocation,
* or an error code in ERR_PTR form.
*
* This macro calls a specified message allocation function, and blocks
* if it returns -ENOBUFS, waiting until quota is available on the service
* before retrying. It aborts the wait if the service resets, or if the
* optionally specified condition becomes false. Note that a reset followed
* quickly by an activate might not trigger a failure; if that is significant
* for your driver, use the optional condition to detect it.
*
* This macro must be called with a reference to the service held, and with
* the service's state lock held. The reference and state lock will still be
* held on return, unless -ENOLINK is returned, in which case the lock has been
* dropped and cannot be reacquired.
*
* This is always an exclusive wait. It is safe to call without separately
* waking the waitqueue afterwards; if the allocator function fails for any
* reason other than quota exhaustion then another waiter will be woken.
*
* Be wary of potential deadlocks when using this macro on the service
* workqueue. If both ends block their service workqueues waiting for quota,
* then no progress can be made. It is usually only correct to block the
* service workqueue on the server side.
*/
#define __vs_wait_alloc(_state, _alloc_func, _cond, _unlock, _intr, \
_timeout, _bh) \
({ \
DEFINE_WAIT(__wait); \
struct vs_mbuf *__mbuf = NULL; \
int __jiffies __maybe_unused = (_timeout); \
struct vs_service_device *__service = (_state)->service;\
\
while (!vs_service_send_mbufs_available(__service)) { \
if (_intr && signal_pending(current)) { \
__mbuf = ERR_PTR(-ERESTARTSYS); \
break; \
} \
\
prepare_to_wait_exclusive( \
&__service->quota_wq, &__wait, \
_intr ? TASK_INTERRUPTIBLE : \
TASK_UNINTERRUPTIBLE); \
\
if (_unlock) \
vs_state_unlock##_bh(_state); \
\
if (_timeout >= 0) { \
__jiffies = schedule_timeout(__jiffies);\
if (!__jiffies) { \
__mbuf = ERR_PTR(-ETIMEDOUT); \
break; \
} \
} else { \
schedule(); \
} \
\
if (_unlock && !vs_state_lock_safe##_bh( \
_state)) { \
__mbuf = ERR_PTR(-ENOLINK); \
break; \
} \
\
if (!VSERVICE_BASE_STATE_IS_RUNNING( \
(_state)->state.base) || \
!(_cond)) { \
__mbuf = ERR_PTR(-ECANCELED); \
break; \
} \
} \
finish_wait(&__service->quota_wq, &__wait); \
\
if (__mbuf == NULL) \
__mbuf = (_alloc_func); \
if (IS_ERR(__mbuf) && (PTR_ERR(__mbuf) != -ENOBUFS)) \
wake_up(&__service->quota_wq); \
__mbuf; \
})
/* Specialisations of __vs_wait_alloc for common uses. */
#define vs_wait_alloc(_state, _cond, _alloc_func) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, true, -1,)
#define vs_wait_alloc_timeout(_state, _cond, _alloc_func, _timeout) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, true, _timeout,)
#define vs_wait_alloc_nointr(_state, _cond, _alloc_func) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, false, -1,)
#define vs_wait_alloc_nointr_timeout(_state, _cond, _alloc_func, _timeout) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, false, _timeout,)
#define vs_wait_alloc_bh(_state, _cond, _alloc_func) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, true, -1, _bh)
#define vs_wait_alloc_timeout_bh(_state, _cond, _alloc_func, _timeout) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, true, _timeout, _bh)
#define vs_wait_alloc_nointr_bh(_state, _cond, _alloc_func) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, false, -1, _bh)
#define vs_wait_alloc_nointr_timeout_bh(_state, _cond, _alloc_func, _timeout) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, false, _timeout, _bh)
#define vs_wait_alloc_locked(_state, _alloc_func) \
__vs_wait_alloc(_state, _alloc_func, true, false, true, -1,)
/* Legacy wait macros, to be removed and replaced with those above. */
/* FIXME: Redmine ticket #229 - philip. */
#define vs_service_waiting_alloc(_state, _alloc_func) \
__vs_wait_alloc(_state, _alloc_func, true, false, true, -1,)
#define vs_service_waiting_alloc_cond_locked(_state, _alloc_func, _cond) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, true, -1,)
#define vs_service_waiting_alloc_cond_locked_nointr(_state, _alloc_func, _cond) \
__vs_wait_alloc(_state, _alloc_func, _cond, true, false, -1,)
/**
* __vs_wait_send - block until quota is available, then send a message.
*
* @_state: The protocol state to send a message for.
* @_cond: Additional condition which must remain true, or else the wait
* will fail with -ECANCELED. This is typically used to check the
* service's protocol state. Note that this condition will only
* be checked after sleeping; it is assumed to be true when the
* macro is first called.
* @_send_func: The message send function to run. This is the full function
* invocation, not a pointer to the function.
* @_unlock: If true, drop the service state lock before sleeping. The wait
* may then fail with -ENOLINK if the driver is detached from the
* service, in which case the lock is dropped.
* @_check_running: If true, the wait will return -ECANCELED if the service's
* base state is not active, or ceases to be active.
* @_intr: If true, perform an interruptible wait; the wait may then fail
* with -ERESTARTSYS.
* @_timeout: A timeout in jiffies, or negative for no timeout. If the
* timeout expires, the wait will fail with -ETIMEDOUT.
* @_bh: The token _bh if this service uses tx_atomic (sends from a
* non-framework tasklet); otherwise nothing.
*
* Return: If the send succeeds, then 0 is returned; otherwise an error
* code may be returned as described above.
*
* This macro calls a specified message send function, and blocks if it
* returns -ENOBUFS, waiting until quota is available on the service before
* retrying. It aborts the wait if it finds the service in reset, or if the
* optionally specified condition becomes false. Note that a reset followed
* quickly by an activate might not trigger a failure; if that is significant
* for your driver, use the optional condition to detect it.
*
* This macro must be called with a reference to the service held, and with
* the service's state lock held. The reference and state lock will still be
* held on return, unless -ENOLINK is returned, in which case the lock has been
* dropped and cannot be reacquired.
*
* This is always an exclusive wait. It is safe to call without separately
* waking the waitqueue afterwards; if the allocator function fails for any
* reason other than quota exhaustion then another waiter will be woken.
*
* Be wary of potential deadlocks when calling this function on the service
* workqueue. If both ends block their service workqueues waiting for quota,
* then no progress can be made. It is usually only correct to block the
* service workqueue on the server side.
*/
#define __vs_wait_send(_state, _cond, _send_func, _unlock, \
_check_running, _intr, _timeout, _bh) \
({ \
DEFINE_WAIT(__wait); \
int __ret = 0; \
int __jiffies __maybe_unused = (_timeout); \
struct vs_service_device *__service = (_state)->service;\
\
while (!vs_service_send_mbufs_available(__service)) { \
if (_intr && signal_pending(current)) { \
__ret = -ERESTARTSYS; \
break; \
} \
\
prepare_to_wait_exclusive( \
&__service->quota_wq, &__wait, \
_intr ? TASK_INTERRUPTIBLE : \
TASK_UNINTERRUPTIBLE); \
\
if (_unlock) \
vs_state_unlock##_bh(_state); \
\
if (_timeout >= 0) { \
__jiffies = schedule_timeout(__jiffies);\
if (!__jiffies) { \
__ret = -ETIMEDOUT; \
break; \
} \
} else { \
schedule(); \
} \
\
if (_unlock && !vs_state_lock_safe##_bh( \
_state)) { \
__ret = -ENOLINK; \
break; \
} \
\
if ((_check_running && \
!VSERVICE_BASE_STATE_IS_RUNNING(\
(_state)->state.base)) || \
!(_cond)) { \
__ret = -ECANCELED; \
break; \
} \
} \
finish_wait(&__service->quota_wq, &__wait); \
\
if (!__ret) \
__ret = (_send_func); \
if ((__ret < 0) && (__ret != -ENOBUFS)) \
wake_up(&__service->quota_wq); \
__ret; \
})
/* Specialisations of __vs_wait_send for common uses. */
#define vs_wait_send(_state, _cond, _send_func) \
__vs_wait_send(_state, _cond, _send_func, true, true, true, -1,)
#define vs_wait_send_timeout(_state, _cond, _send_func, _timeout) \
__vs_wait_send(_state, _cond, _send_func, true, true, true, _timeout,)
#define vs_wait_send_nointr(_state, _cond, _send_func) \
__vs_wait_send(_state, _cond, _send_func, true, true, false, -1,)
#define vs_wait_send_nointr_timeout(_state, _cond, _send_func, _timeout) \
__vs_wait_send(_state, _cond, _send_func, true, true, false, _timeout,)
#define vs_wait_send_bh(_state, _cond, _send_func) \
__vs_wait_send(_state, _cond, _send_func, true, true, true, -1, _bh)
#define vs_wait_send_timeout_bh(_state, _cond, _send_func, _timeout) \
__vs_wait_send(_state, _cond, _send_func, true, true, true, \
_timeout, _bh)
#define vs_wait_send_nointr_bh(_state, _cond, _send_func) \
__vs_wait_send(_state, _cond, _send_func, true, true, false, -1, _bh)
#define vs_wait_send_nointr_timeout_bh(_state, _cond, _send_func, _timeout) \
__vs_wait_send(_state, _cond, _send_func, true, true, false, \
_timeout, _bh)
#define vs_wait_send_locked(_state, _send_func) \
__vs_wait_send(_state, true, _send_func, false, true, true, -1,)
#define vs_wait_send_locked_nocheck(_state, _send_func) \
__vs_wait_send(_state, true, _send_func, false, false, true, -1,)
/* Legacy wait macros, to be removed and replaced with those above. */
/* FIXME: Redmine ticket #229 - philip. */
#define vs_service_waiting_send(_state, _send_func) \
__vs_wait_send(_state, true, _send_func, true, true, true, -1,)
#define vs_service_waiting_send_nointr(_state, _send_func) \
__vs_wait_send(_state, true, _send_func, true, true, false, -1,)
#define vs_service_waiting_send_cond(_state, _cond, _send_func) \
__vs_wait_send(_state, _cond, _send_func, true, true, true, -1,)
#define vs_service_waiting_send_cond_nointr(_state, _cond, _send_func) \
__vs_wait_send(_state, _cond, _send_func, true, true, false, -1,)
#define vs_service_waiting_send_nocheck(_state, _send_func) \
__vs_wait_send(_state, true, _send_func, true, false, true, -1,)
#endif /* _VSERVICE_SERVICE_WAIT_H */