diff --git a/BLD/build/HEADERS/92-vmkdrivers-asm-x64/vmkernel64/release/asm/semaphore.h b/BLD/build/HEADERS/92-vmkdrivers-asm-x64/vmkernel64/release/asm/semaphore.h new file mode 100644 index 0000000000000000000000000000000000000000..3ef4c46312133164786d93647003af45af787c4f --- /dev/null +++ b/BLD/build/HEADERS/92-vmkdrivers-asm-x64/vmkernel64/release/asm/semaphore.h @@ -0,0 +1,391 @@ +/* + * Portions Copyright 2008 VMware, Inc. + */ +#ifndef _X86_64_SEMAPHORE_H +#define _X86_64_SEMAPHORE_H + +#include + +#ifdef __KERNEL__ + +/* + * SMP- and interrupt-safe semaphores.. + * + * (C) Copyright 1996 Linus Torvalds + * + * Modified 1996-12-23 by Dave Grothe to fix bugs in + * the original code and to make semaphore waits + * interruptible so that processes waiting on + * semaphores can be killed. + * Modified 1999-02-14 by Andrea Arcangeli, split the sched.c helper + * functions in asm/sempahore-helper.h while fixing a + * potential and subtle race discovered by Ulrich Schmid + * in down_interruptible(). Since I started to play here I + * also implemented the `trylock' semaphore operation. + * 1999-07-02 Artur Skawina + * Optimized "0(ecx)" -> "(ecx)" (the assembler does not + * do this). Changed calling sequences from push/jmp to + * traditional call/ret. + * Modified 2001-01-01 Andreas Franck + * Some hacks to ensure compatibility with recent + * GCC snapshots, to avoid stack corruption when compiling + * with -fomit-frame-pointer. It's not sure if this will + * be fixed in GCC, as our previous implementation was a + * bit dubious. + * + * If you would like to see an analysis of this implementation, please + * ftp to gcom.com and download the file + * /pub/linux/src/semaphore/semaphore-2.0.24.tar.gz. + * + */ + +#include +#include +#include +#include +#include +#include + +#if defined(__VMKLNX__) +#include "vmkapi.h" +#endif /* defined(__VMKLNX__) */ + +struct semaphore { + atomic_t count; + int sleepers; + wait_queue_head_t wait; +}; + +/** + * __SEMAPHORE_INITIALIZER - initialize the semaphore + * @name: name of the semaphore + * @n: count for the semaphore + * + * Initialize the semaphore and set its count to @n, the number of sleepers to + * 0 and initialize its wait queue. + * + * RETURN VALUE: + * This function does not return a value. + */ +/* _VMKLNX_CODECHECK_: __SEMAPHORE_INITIALIZER */ +#define __SEMAPHORE_INITIALIZER(name, n) \ +{ \ + .count = ATOMIC_INIT(n), \ + .sleepers = 0, \ + .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ +} + +#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ + struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) + +#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) +#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0) + +/** + * sema_init - Initializes semaphore value + * @sem: semaphore + * @val: value + * + * Initilizes semaphore value + * + * RETURN VALUE: + * NONE + * + */ +/* _VMKLNX_CODECHECK_: sema_init */ +static inline void sema_init (struct semaphore *sem, int val) +{ +/* + * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); + * + * i'd rather use the more flexible initialization above, but sadly + * GCC 2.7.2.3 emits a bogus warning. EGCS doesn't. Oh well. + */ + atomic_set(&sem->count, val); + sem->sleepers = 0; + init_waitqueue_head(&sem->wait); +} + +/** + * init_MUTEX - Initializes the semaphore as free resource with exclusive access. + * @sem: Pointer to semaphore + * + * The given semaphore is initialized as a free resource with exclusive + * access. + * + * RETURN VALUE: + * NONE + * + */ +/* _VMKLNX_CODECHECK_: init_MUTEX */ +static inline void init_MUTEX (struct semaphore *sem) +{ + sema_init(sem, 1); +} + +/** + * init_MUTEX_LOCKED - Initializes the semaphore as busy resource with exclusive access. + * @sem: Pointer to semaphore. + * + * The given semaphore is initialized as a busy resource with exclusive access + * given to the caller of the initialization function. + * + * RETURN VALUE: + * NONE + */ +/* _VMKLNX_CODECHECK_: init_MUTEX_LOCKED */ +static inline void init_MUTEX_LOCKED (struct semaphore *sem) +{ + sema_init(sem, 0); +} + +asmlinkage void __down_failed(void /* special register calling convention */); +asmlinkage int __down_failed_interruptible(void /* params in registers */); +asmlinkage int __down_failed_trylock(void /* params in registers */); +asmlinkage void __up_wakeup(void /* special register calling convention */); + +asmlinkage void __down(struct semaphore * sem); +asmlinkage int __down_interruptible(struct semaphore * sem); +asmlinkage int __down_trylock(struct semaphore * sem); +asmlinkage void __up(struct semaphore * sem); + +/* + * This is ugly, but we want the default case to fall through. + * "__down_failed" is a special asm handler that calls the C + * routine that actually waits. See arch/x86_64/kernel/semaphore.c + */ +/** + * down - acquire a semaphore + * @sem: Pointer to the semaphore to be acquired + * + * Acquires the specified semaphore. If the semaphore's count of available + * acquisitions is exhausted, then the calling function will block. + * + * RETURN VALUE: + * None + */ +/* _VMKLNX_CODECHECK_: down */ +static inline void down(struct semaphore * sem) +{ + might_sleep(); + +#if defined(__VMKLNX__) + vmk_AtomicPrologue(); + __asm__ __volatile__( + "# atomic down operation\n\t" + LOCK_PREFIX "decl %0\n\t" /* --sem->count */ + "js 2f\n" + "cmpb $0, vmk_AtomicUseFence(%%rip)\n" + "jne 4f\n" + "1:\n" + LOCK_SECTION_START("") + "2:\tcmpb $0, vmk_AtomicUseFence(%%rip)\n" + "jne 3f\n" + "call __down_failed\n\t" + "jmp 1b\n" + "3:\tlfence\n" + "call __down_failed\n\t" + "jmp 1b\n" + "4:\tlfence\n" + "jmp 1b\n" + LOCK_SECTION_END + :"=m" (sem->count) + :"D" (sem) + :"memory"); +#else /* !defined(__VMKLNX__) */ + __asm__ __volatile__( + "# atomic down operation\n\t" + LOCK_PREFIX "decl %0\n\t" /* --sem->count */ + "js 2f\n" + "1:\n" + LOCK_SECTION_START("") + "2:\tcall __down_failed\n\t" + "jmp 1b\n" + LOCK_SECTION_END + :"=m" (sem->count) + :"D" (sem) + :"memory"); +#endif /* !defined(__VMKLNX__) */ +} + +/* + * Interruptible try to acquire a semaphore. If we obtained + * it, return zero. If we were interrupted, returns -EINTR + */ +/** + * down_interruptible - Acquire a semaphore with an interruptible wait + * @sem: Pointer to the semaphore to be acquired + * + * Attempt to acquire the specified semaphore. If the semaphore's count of available + * acquisitions is exhausted, then the calling function will block. If a + * signal is received by the blocking thread, then this function aborts. + * + * RETURN VALUE: + * 0 on successful acquisition, or -EINTR if interrupted by a signal + */ +/* _VMKLNX_CODECHECK_: down_interruptible */ +static inline int down_interruptible(struct semaphore * sem) +{ + int result; + + might_sleep(); + +#if defined(__VMKLNX__) + vmk_AtomicPrologue(); + __asm__ __volatile__( + "# atomic interruptible down operation\n\t" + LOCK_PREFIX "decl %1\n\t" /* --sem->count */ + "js 2f\n\t" + "xorl %0,%0\n" + "cmpb $0, vmk_AtomicUseFence(%%rip)\n\t" + "jne 4f\n" + "1:\n" + LOCK_SECTION_START("") + "2:\tcmpb $0, vmk_AtomicUseFence(%%rip)\n\t" + "jne 3f\n" + "call __down_failed_interruptible\n\t" + "jmp 1b\n" + "3:\tlfence\n" + "call __down_failed_interruptible\n\t" + "jmp 1b\n" + "4:\tlfence\n" + "jmp 1b\n" + LOCK_SECTION_END + :"=a" (result), "=m" (sem->count) + :"D" (sem) + :"memory"); +#else /* !defined(__VMKLNX__) */ + __asm__ __volatile__( + "# atomic interruptible down operation\n\t" + LOCK_PREFIX "decl %1\n\t" /* --sem->count */ + "js 2f\n\t" + "xorl %0,%0\n" + "1:\n" + LOCK_SECTION_START("") + "2:\tcall __down_failed_interruptible\n\t" + "jmp 1b\n" + LOCK_SECTION_END + :"=a" (result), "=m" (sem->count) + :"D" (sem) + :"memory"); +#endif /* !defined(__VMKLNX__) */ + return result; +} + +/* + * Non-blockingly attempt to down() a semaphore. + * Returns zero if we acquired it + */ +/** + * down_trylock - attempt to acquire a semaphore + * @sem: Pointer to the semaphore to be acquired + * + * Attempt to acquire the specified semaphore. If the semaphore's count of available + * acquisitions is exhausted, then return immediately. + * + * RETURN VALUE: + * 0 on successful acquisition, or 1 if the semaphore is not immediately available + */ +/* _VMKLNX_CODECHECK_: down_trylock */ +static inline int down_trylock(struct semaphore * sem) +{ + int result; + +#if defined(__VMKLNX__) + vmk_AtomicPrologue(); + __asm__ __volatile__( + "# atomic interruptible down operation\n\t" + LOCK_PREFIX "decl %1\n\t" /* --sem->count */ + "js 2f\n\t" + "xorl %0,%0\n" + "cmpb $0, vmk_AtomicUseFence(%%rip)\n\t" + "jne 4f\n" + "1:\n" + LOCK_SECTION_START("") + "2:\tcmpb $0, vmk_AtomicUseFence(%%rip)\n\t" + "jne 3f\n" + "call __down_failed_trylock\n\t" + "jmp 1b\n" + "3:\tlfence\n" + "call __down_failed_trylock\n\t" + "jmp 1b\n" + "4:\tlfence\n" + "jmp 1b\n" + LOCK_SECTION_END + :"=a" (result), "=m" (sem->count) + :"D" (sem) + :"memory","cc"); +#else /* !defined(__VMKLNX__) */ + __asm__ __volatile__( + "# atomic interruptible down operation\n\t" + LOCK_PREFIX "decl %1\n\t" /* --sem->count */ + "js 2f\n\t" + "xorl %0,%0\n" + "1:\n" + LOCK_SECTION_START("") + "2:\tcall __down_failed_trylock\n\t" + "jmp 1b\n" + LOCK_SECTION_END + :"=a" (result), "=m" (sem->count) + :"D" (sem) + :"memory","cc"); +#endif /* !defined(__VMKLNX__) */ + return result; +} + +/* + * Note! This is subtle. We jump to wake people up only if + * the semaphore was negative (== somebody was waiting on it). + * The default case (no contention) will result in NO + * jumps for both down() and up(). + */ +/** + * up - release semaphore + * @sem: pointer to initialized and acquired semaphore + * + * RETURN VALUE: + * none + */ + /* _VMKLNX_CODECHECK_: up */ +static inline void up(struct semaphore * sem) +{ +#if defined(__VMKLNX__) + vmk_AtomicPrologue(); + __asm__ __volatile__( + "# atomic up operation\n\t" + LOCK_PREFIX "incl %0\n\t" /* ++sem->count */ + "jle 2f\n" + "cmpb $0, vmk_AtomicUseFence(%%rip)\n\t" + "jne 4f\n" + "1:\n" + LOCK_SECTION_START("") + "2:\tcmpb $0, vmk_AtomicUseFence(%%rip)\n\t" + "jne 3f\n" + "call __up_wakeup\n\t" + "jmp 1b\n" + "3:\tlfence\n" + "call __up_wakeup\n\t" + "jmp 1b\n" + "4:\tlfence\n" + "jmp 1b\n" + LOCK_SECTION_END + :"=m" (sem->count) + :"D" (sem) + :"memory"); +#else /* !defined(__VMKLNX__) */ + __asm__ __volatile__( + "# atomic up operation\n\t" + LOCK_PREFIX "incl %0\n\t" /* ++sem->count */ + "jle 2f\n" + "1:\n" + LOCK_SECTION_START("") + "2:\tcall __up_wakeup\n\t" + "jmp 1b\n" + LOCK_SECTION_END + :"=m" (sem->count) + :"D" (sem) + :"memory"); +#endif /* !defined(__VMKLNX__) */ +} +#endif /* __KERNEL__ */ +#endif