kernel & libroot: Implement per-team unnamed semaphores.

This requires breaking syscall ABI to add the "flags" parameter
to _kern_mutex_sem_release.

Resolves a TODO.

headers/private/kernel/user_mutex.h

@@ -25,7 +25,7 @@ status_t	_user_mutex_switch_lock(int32* fromMutex, uint32 fromFlags,
 				int32* toMutex, const char* name, uint32 toFlags, bigtime_t timeout);
 status_t	_user_mutex_sem_acquire(int32* sem, const char* name, uint32 flags,
 				bigtime_t timeout);
-status_t	_user_mutex_sem_release(int32* sem);
+status_t	_user_mutex_sem_release(int32* sem, uint32 flags);
 
 #ifdef __cplusplus
 }

headers/private/system/syscalls.h

@@ -83,7 +83,7 @@ extern status_t		_kern_mutex_switch_lock(int32* fromMutex, uint32 fromFlags,
 						bigtime_t timeout);
 extern status_t		_kern_mutex_sem_acquire(int32* sem, const char* name,
 						uint32 flags, bigtime_t timeout);
-extern status_t		_kern_mutex_sem_release(int32* sem);
+extern status_t		_kern_mutex_sem_release(int32* sem, uint32 flags);
 
 /* sem functions */
 extern sem_id		_kern_create_sem(int count, const char *name);

src/system/kernel/locks/user_mutex.cpp

@@ -660,58 +660,43 @@ _user_mutex_sem_acquire(int32* sem, const char* name, uint32 flags,
 
 	syscall_restart_handle_timeout_pre(flags, timeout);
 
-	struct user_mutex_context* context;
+	UserMutexContextFetcher contextFetcher(sem, flags);
+	if (contextFetcher.InitCheck() != B_OK)
+		return contextFetcher.InitCheck();
+	struct user_mutex_context* context = contextFetcher.Context();
 
-	// TODO: use the per-team context when possible
-	context = &sSharedUserMutexContext;
-
-	// wire the page and get the physical address
-	VMPageWiringInfo wiringInfo;
-	status_t error = vm_wire_page(B_CURRENT_TEAM, (addr_t)sem, true,
-		&wiringInfo);
-	if (error != B_OK)
-		return error;
-
-	UserMutexEntry* entry = get_user_mutex_entry(context, wiringInfo.physicalAddress);
+	UserMutexEntry* entry = get_user_mutex_entry(context, contextFetcher.Address());
 	if (entry == NULL)
 		return B_NO_MEMORY;
+	status_t error;
 	{
 		ReadLocker entryLocker(entry->lock);
 		error = user_mutex_sem_acquire_locked(entry, sem,
-			flags | B_CAN_INTERRUPT, timeout, entryLocker, true);
+			flags | B_CAN_INTERRUPT, timeout, entryLocker, contextFetcher.IsWired());
 	}
 	put_user_mutex_entry(context, entry);
 
-	vm_unwire_page(&wiringInfo);
 	return syscall_restart_handle_timeout_post(error, timeout);
 }
 
 
 status_t
-_user_mutex_sem_release(int32* sem)
+_user_mutex_sem_release(int32* sem, uint32 flags)
 {
 	if (sem == NULL || !IS_USER_ADDRESS(sem) || (addr_t)sem % 4 != 0)
 		return B_BAD_ADDRESS;
 
-	struct user_mutex_context* context;
-
-	// TODO: use the per-team context when possible
-	context = &sSharedUserMutexContext;
-
-	// wire the page and get the physical address
-	VMPageWiringInfo wiringInfo;
-	status_t error = vm_wire_page(B_CURRENT_TEAM, (addr_t)sem, true,
-		&wiringInfo);
-	if (error != B_OK)
-		return error;
+	UserMutexContextFetcher contextFetcher(sem, flags);
+	if (contextFetcher.InitCheck() != B_OK)
+		return contextFetcher.InitCheck();
+	struct user_mutex_context* context = contextFetcher.Context();
 
 	UserMutexEntry* entry = get_user_mutex_entry(context,
-		wiringInfo.physicalAddress);
+		contextFetcher.Address());
 	{
-		user_mutex_sem_release(entry, sem, true);
+		user_mutex_sem_release(entry, sem, contextFetcher.IsWired());
 	}
 	put_user_mutex_entry(context, entry);
 
-	vm_unwire_page(&wiringInfo);
 	return B_OK;
 }

src/system/libroot/posix/semaphore.cpp

@@ -24,6 +24,7 @@
 
 #define SEM_TYPE_NAMED		1
 #define SEM_TYPE_UNNAMED	2
+#define SEM_TYPE_UNNAMED_SHARED 3
 
 
 static int32
@@ -114,7 +115,7 @@ sem_unlink(const char* name)
 int
 sem_init(sem_t* semaphore, int shared, unsigned value)
 {
-	semaphore->type = SEM_TYPE_UNNAMED;
+	semaphore->type = shared ? SEM_TYPE_UNNAMED_SHARED : SEM_TYPE_UNNAMED;
 	semaphore->u.unnamed_sem = value;
 	return 0;
 }
@@ -123,7 +124,7 @@ sem_init(sem_t* semaphore, int shared, unsigned value)
 int
 sem_destroy(sem_t* semaphore)
 {
-	if (semaphore->type != SEM_TYPE_UNNAMED)
+	if (semaphore->type != SEM_TYPE_UNNAMED && semaphore->type != SEM_TYPE_UNNAMED_SHARED)
 		RETURN_AND_SET_ERRNO(EINVAL);
 
 	return 0;
@@ -138,7 +139,11 @@ unnamed_sem_post(sem_t* semaphore)
 	if (oldValue > -1)
 		return 0;
 
-	return _kern_mutex_sem_release(sem);
+	uint32 flags = 0;
+	if (semaphore->type == SEM_TYPE_UNNAMED_SHARED)
+		flags |= B_USER_MUTEX_SHARED;
+
+	return _kern_mutex_sem_release(sem, flags);
 }
 
 
@@ -162,6 +167,8 @@ unnamed_sem_timedwait(sem_t* semaphore, clockid_t clock_id,
 
 	bigtime_t timeoutMicros = B_INFINITE_TIMEOUT;
 	uint32 flags = 0;
+	if (semaphore->type == SEM_TYPE_UNNAMED_SHARED)
+		flags |= B_USER_MUTEX_SHARED;
 	if (timeout != NULL) {
 		timeoutMicros = ((bigtime_t)timeout->tv_sec) * 1000000
 			+ timeout->tv_nsec / 1000;