+++ /dev/null
-/*********************************************************
- * Copyright (C) 2004 VMware, Inc. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation version 2 and no later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- *
- *********************************************************/
-
-#ifndef __COMPAT_COMPLETION_H__
-# define __COMPAT_COMPLETION_H__
-
-/*
- * The kernel's completion objects were made available for module use in 2.4.9.
- *
- * Between 2.4.0 and 2.4.9, we implement completions on our own using
- * waitqueues and counters. This was done so that we could safely support
- * functions like complete_all(), which cannot be implemented using semaphores.
- *
- * Prior to that, the waitqueue API is substantially different, and since none
- * of our modules that are built against older kernels need complete_all(),
- * we fallback on a simple semaphore-based implementation.
- */
-
-/*
- * Native completions.
- */
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 9)
-
-#include <linux/completion.h>
-#define compat_completion struct completion
-#define compat_init_completion(comp) init_completion(comp)
-#define COMPAT_DECLARE_COMPLETION DECLARE_COMPLETION
-#define compat_wait_for_completion(comp) wait_for_completion(comp)
-#define compat_complete(comp) complete(comp)
-
-/* complete_all() was exported in 2.6.6. */
-# if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 6)
-# include "compat_wait.h"
-# include "compat_list.h"
-# include "compat_spinlock.h"
-# include "compat_sched.h"
-# define compat_complete_all(x) \
- ({ \
- struct list_head *currLinks; \
- spin_lock(&(x)->wait.lock); \
- (x)->done += UINT_MAX/2; \
- \
- list_for_each(currLinks, &(x)->wait.task_list) { \
- wait_queue_t *currQueue = list_entry(currLinks, wait_queue_t, task_list); \
- wake_up_process(currQueue->task); \
- } \
- spin_unlock(&(x)->wait.lock); \
- })
-# else
-# define compat_complete_all complete_all
-# endif
-
-/*
- * Completions via waitqueues.
- */
-#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 0)
-
-/*
- * Kernel completions in 2.4.9 and beyond use a counter and a waitqueue, and
- * our implementation is quite similar. Because __wake_up_common() is not
- * exported, our implementations of compat_complete() and compat_complete_all()
- * are somewhat racy: the counter is incremented outside of the waitqueue's
- * lock.
- *
- * As a result, our completion cannot guarantee in-order wake ups. For example,
- * suppose thread A is entering compat_complete(), thread B is sleeping inside
- * compat_wait_for_completion(), and thread C is just now entering
- * compat_wait_for_completion(). If Thread A is scheduled first and increments
- * the counter, then gets swapped out, thread C may get scheduled and will
- * quickly go through compat_wait_for_completion() (since done != 0) while
- * thread B continues to sleep, even though thread B should have been the one
- * to wake up.
- */
-
-#include <asm/current.h>
-#include "compat_sched.h"
-#include "compat_list.h"
-#include <linux/smp_lock.h> // for lock_kernel()/unlock_kernel()
-#include "compat_wait.h"
-
-typedef struct compat_completion {
- unsigned int done;
- wait_queue_head_t wq;
-} compat_completion;
-
-#define compat_init_completion(comp) do { \
- (comp)->done = 0; \
- init_waitqueue_head(&(comp)->wq); \
-} while (0)
-#define COMPAT_DECLARE_COMPLETION(comp) \
- compat_completion comp = { \
- .done = 0, \
- .wq = __WAIT_QUEUE_HEAD_INITIALIZER((comp).wq), \
- }
-
-/*
- * Locking and unlocking the kernel lock here ensures that the thread
- * is no longer running in module code: compat_complete_and_exit
- * performs the sequence { lock_kernel(); up(comp); compat_exit(); }, with
- * the final unlock_kernel performed implicitly by the resident kernel
- * in do_exit.
- */
-#define compat_wait_for_completion(comp) do { \
- spin_lock_irq(&(comp)->wq.lock); \
- if (!(comp)->done) { \
- DECLARE_WAITQUEUE(wait, current); \
- wait.flags |= WQ_FLAG_EXCLUSIVE; \
- __add_wait_queue_tail(&(comp)->wq, &wait); \
- do { \
- __set_current_state(TASK_UNINTERRUPTIBLE); \
- spin_unlock_irq(&(comp)->wq.lock); \
- schedule(); \
- spin_lock_irq(&(comp)->wq.lock); \
- } while (!(comp)->done); \
- __remove_wait_queue(&(comp)->wq, &wait); \
- } \
- (comp)->done--; \
- spin_unlock_irq(&(comp)->wq.lock); \
- lock_kernel(); \
- unlock_kernel(); \
-} while (0)
-
-/* XXX: I don't think I need to touch the BKL. */
-#define compat_complete(comp) do { \
- unsigned long flags; \
- spin_lock_irqsave(&(comp)->wq.lock, flags); \
- (comp)->done++; \
- spin_unlock_irqrestore(&(comp)->wq.lock, flags); \
- wake_up(&(comp)->wq); \
-} while (0)
-
-#define compat_complete_all(comp) do { \
- unsigned long flags; \
- spin_lock_irqsave(&(comp)->wq.lock, flags); \
- (comp)->done += UINT_MAX / 2; \
- spin_unlock_irqrestore(&(comp)->wq.lock, flags); \
- wake_up_all(&(comp)->wq); \
-} while (0)
-
-/*
- * Completions via semaphores.
- */
-#else
-
-#include "compat_semaphore.h"
-#define compat_completion struct semaphore
-#define compat_init_completion(comp) init_MUTEX_LOCKED(comp)
-#define COMPAT_DECLARE_COMPLETION(comp) DECLARE_MUTEX_LOCKED(comp)
-
-#define compat_wait_for_completion(comp) do { \
- down(comp); \
- lock_kernel(); \
- unlock_kernel(); \
-} while (0)
-
-#define compat_complete(comp) up(comp)
-
-#endif
-
-#endif /* __COMPAT_COMPLETION_H__ */
(type *)( (char *)__mptr - offsetof(type,member) );})
#endif
-/*
- * wait_for_completion and friends did not exist before 2.4.9.
- */
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 9)
-
-#define compat_complete_and_exit(comp, status) complete_and_exit(comp, status)
-
-#else
-
-#include "compat_completion.h"
-
-/*
- * Used by _syscallX macros. Note that this is global variable, so
- * do not rely on its contents too much. As exit() is only function
- * we use, and we never check return value from exit(), we have
- * no problem...
- */
-extern int errno;
-
-/*
- * compat_exit() provides an access to the exit() function. It must
- * be named compat_exit(), as exit() (with different signature) is
- * provided by x86-64, arm and other (but not by i386).
- */
-#define __NR_compat_exit __NR_exit
-static inline _syscall1(int, compat_exit, int, exit_code);
-
-/*
- * See compat_wait_for_completion in compat_completion.h.
- * compat_exit implicitly performs an unlock_kernel, in resident code,
- * ensuring that the thread is no longer running in module code when the
- * module is unloaded.
- */
-#define compat_complete_and_exit(comp, status) do { \
- lock_kernel(); \
- compat_complete(comp); \
- compat_exit(status); \
-} while (0)
-
-#endif
-
/*
* vsnprintf became available in 2.4.10. For older kernels, just fall back on
* vsprintf.
projects / thirdparty / open-vm-tools.git / commitdiff
