satip-axe/kernel/arch/powerpc/platforms/cell/spu_syscalls.c
2015-03-26 17:24:57 +01:00

179 lines
3.8 KiB
C

/*
* SPU file system -- system call stubs
*
* (C) Copyright IBM Deutschland Entwicklung GmbH 2005
* (C) Copyright 2006-2007, IBM Corporation
*
* Author: Arnd Bergmann <arndb@de.ibm.com>
*
* 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; either version 2, or (at your option)
* any 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/syscalls.h>
#include <linux/rcupdate.h>
#include <asm/spu.h>
/* protected by rcu */
static struct spufs_calls *spufs_calls;
#ifdef CONFIG_SPU_FS_MODULE
static inline struct spufs_calls *spufs_calls_get(void)
{
struct spufs_calls *calls = NULL;
rcu_read_lock();
calls = rcu_dereference(spufs_calls);
if (calls && !try_module_get(calls->owner))
calls = NULL;
rcu_read_unlock();
return calls;
}
static inline void spufs_calls_put(struct spufs_calls *calls)
{
BUG_ON(calls != spufs_calls);
/* we don't need to rcu this, as we hold a reference to the module */
module_put(spufs_calls->owner);
}
#else /* !defined CONFIG_SPU_FS_MODULE */
static inline struct spufs_calls *spufs_calls_get(void)
{
return spufs_calls;
}
static inline void spufs_calls_put(struct spufs_calls *calls) { }
#endif /* CONFIG_SPU_FS_MODULE */
asmlinkage long sys_spu_create(const char __user *name,
unsigned int flags, mode_t mode, int neighbor_fd)
{
long ret;
struct file *neighbor;
int fput_needed;
struct spufs_calls *calls;
calls = spufs_calls_get();
if (!calls)
return -ENOSYS;
if (flags & SPU_CREATE_AFFINITY_SPU) {
ret = -EBADF;
neighbor = fget_light(neighbor_fd, &fput_needed);
if (neighbor) {
ret = calls->create_thread(name, flags, mode, neighbor);
fput_light(neighbor, fput_needed);
}
} else
ret = calls->create_thread(name, flags, mode, NULL);
spufs_calls_put(calls);
return ret;
}
asmlinkage long sys_spu_run(int fd, __u32 __user *unpc, __u32 __user *ustatus)
{
long ret;
struct file *filp;
int fput_needed;
struct spufs_calls *calls;
calls = spufs_calls_get();
if (!calls)
return -ENOSYS;
ret = -EBADF;
filp = fget_light(fd, &fput_needed);
if (filp) {
ret = calls->spu_run(filp, unpc, ustatus);
fput_light(filp, fput_needed);
}
spufs_calls_put(calls);
return ret;
}
int elf_coredump_extra_notes_size(void)
{
struct spufs_calls *calls;
int ret;
calls = spufs_calls_get();
if (!calls)
return 0;
ret = calls->coredump_extra_notes_size();
spufs_calls_put(calls);
return ret;
}
int elf_coredump_extra_notes_write(struct file *file, loff_t *foffset)
{
struct spufs_calls *calls;
int ret;
calls = spufs_calls_get();
if (!calls)
return 0;
ret = calls->coredump_extra_notes_write(file, foffset);
spufs_calls_put(calls);
return ret;
}
void notify_spus_active(void)
{
struct spufs_calls *calls;
calls = spufs_calls_get();
if (!calls)
return;
calls->notify_spus_active();
spufs_calls_put(calls);
return;
}
int register_spu_syscalls(struct spufs_calls *calls)
{
if (spufs_calls)
return -EBUSY;
rcu_assign_pointer(spufs_calls, calls);
return 0;
}
EXPORT_SYMBOL_GPL(register_spu_syscalls);
void unregister_spu_syscalls(struct spufs_calls *calls)
{
BUG_ON(spufs_calls->owner != calls->owner);
rcu_assign_pointer(spufs_calls, NULL);
synchronize_rcu();
}
EXPORT_SYMBOL_GPL(unregister_spu_syscalls);