summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/platforms/cell/spu_syscalls.c
blob: 38e0a1a5cec34d500475ff3aa22e08254fe82174 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
/*
 * 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 <linux/binfmts.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 */

SYSCALL_DEFINE4(spu_create, const char __user *, name, unsigned int, flags,
	umode_t, mode, int, neighbor_fd)
{
	long ret;
	struct spufs_calls *calls;

	calls = spufs_calls_get();
	if (!calls)
		return -ENOSYS;

	if (flags & SPU_CREATE_AFFINITY_SPU) {
		struct fd neighbor = fdget(neighbor_fd);
		ret = -EBADF;
		if (neighbor.file) {
			ret = calls->create_thread(name, flags, mode, neighbor.file);
			fdput(neighbor);
		}
	} 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 fd arg;
	struct spufs_calls *calls;

	calls = spufs_calls_get();
	if (!calls)
		return -ENOSYS;

	ret = -EBADF;
	arg = fdget(fd);
	if (arg.file) {
		ret = calls->spu_run(arg.file, unpc, ustatus);
		fdput(arg);
	}

	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 coredump_params *cprm)
{
	struct spufs_calls *calls;
	int ret;

	calls = spufs_calls_get();
	if (!calls)
		return 0;

	ret = calls->coredump_extra_notes_write(cprm);

	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_INIT_POINTER(spufs_calls, NULL);
	synchronize_rcu();
}
EXPORT_SYMBOL_GPL(unregister_spu_syscalls);