1 /*
2 * SPU file system -- system call stubs
3 *
4 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
5 * (C) Copyright 2006-2007, IBM Corporation
6 *
7 * Author: Arnd Bergmann <arndb@de.ibm.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2, or (at your option)
12 * any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 */
23 #include <linux/file.h>
24 #include <linux/fs.h>
25 #include <linux/module.h>
26 #include <linux/syscalls.h>
27 #include <linux/rcupdate.h>
28 #include <linux/binfmts.h>
29 #include <linux/syscalls.h>
30
31 #include <asm/spu.h>
32
33 /* protected by rcu */
34 static struct spufs_calls *spufs_calls;
35
36 #ifdef CONFIG_SPU_FS_MODULE
37
spufs_calls_get(void)38 static inline struct spufs_calls *spufs_calls_get(void)
39 {
40 struct spufs_calls *calls = NULL;
41
42 rcu_read_lock();
43 calls = rcu_dereference(spufs_calls);
44 if (calls && !try_module_get(calls->owner))
45 calls = NULL;
46 rcu_read_unlock();
47
48 return calls;
49 }
50
spufs_calls_put(struct spufs_calls * calls)51 static inline void spufs_calls_put(struct spufs_calls *calls)
52 {
53 BUG_ON(calls != spufs_calls);
54
55 /* we don't need to rcu this, as we hold a reference to the module */
56 module_put(spufs_calls->owner);
57 }
58
59 #else /* !defined CONFIG_SPU_FS_MODULE */
60
spufs_calls_get(void)61 static inline struct spufs_calls *spufs_calls_get(void)
62 {
63 return spufs_calls;
64 }
65
spufs_calls_put(struct spufs_calls * calls)66 static inline void spufs_calls_put(struct spufs_calls *calls) { }
67
68 #endif /* CONFIG_SPU_FS_MODULE */
69
SYSCALL_DEFINE4(spu_create,const char __user *,name,unsigned int,flags,umode_t,mode,int,neighbor_fd)70 SYSCALL_DEFINE4(spu_create, const char __user *, name, unsigned int, flags,
71 umode_t, mode, int, neighbor_fd)
72 {
73 long ret;
74 struct spufs_calls *calls;
75
76 calls = spufs_calls_get();
77 if (!calls)
78 return -ENOSYS;
79
80 if (flags & SPU_CREATE_AFFINITY_SPU) {
81 struct fd neighbor = fdget(neighbor_fd);
82 ret = -EBADF;
83 if (neighbor.file) {
84 ret = calls->create_thread(name, flags, mode, neighbor.file);
85 fdput(neighbor);
86 }
87 } else
88 ret = calls->create_thread(name, flags, mode, NULL);
89
90 spufs_calls_put(calls);
91 return ret;
92 }
93
SYSCALL_DEFINE3(spu_run,int,fd,__u32 __user *,unpc,__u32 __user *,ustatus)94 SYSCALL_DEFINE3(spu_run,int, fd, __u32 __user *, unpc, __u32 __user *, ustatus)
95 {
96 long ret;
97 struct fd arg;
98 struct spufs_calls *calls;
99
100 calls = spufs_calls_get();
101 if (!calls)
102 return -ENOSYS;
103
104 ret = -EBADF;
105 arg = fdget(fd);
106 if (arg.file) {
107 ret = calls->spu_run(arg.file, unpc, ustatus);
108 fdput(arg);
109 }
110
111 spufs_calls_put(calls);
112 return ret;
113 }
114
115 #ifdef CONFIG_COREDUMP
elf_coredump_extra_notes_size(void)116 int elf_coredump_extra_notes_size(void)
117 {
118 struct spufs_calls *calls;
119 int ret;
120
121 calls = spufs_calls_get();
122 if (!calls)
123 return 0;
124
125 ret = calls->coredump_extra_notes_size();
126
127 spufs_calls_put(calls);
128
129 return ret;
130 }
131
elf_coredump_extra_notes_write(struct coredump_params * cprm)132 int elf_coredump_extra_notes_write(struct coredump_params *cprm)
133 {
134 struct spufs_calls *calls;
135 int ret;
136
137 calls = spufs_calls_get();
138 if (!calls)
139 return 0;
140
141 ret = calls->coredump_extra_notes_write(cprm);
142
143 spufs_calls_put(calls);
144
145 return ret;
146 }
147 #endif
148
notify_spus_active(void)149 void notify_spus_active(void)
150 {
151 struct spufs_calls *calls;
152
153 calls = spufs_calls_get();
154 if (!calls)
155 return;
156
157 calls->notify_spus_active();
158 spufs_calls_put(calls);
159
160 return;
161 }
162
register_spu_syscalls(struct spufs_calls * calls)163 int register_spu_syscalls(struct spufs_calls *calls)
164 {
165 if (spufs_calls)
166 return -EBUSY;
167
168 rcu_assign_pointer(spufs_calls, calls);
169 return 0;
170 }
171 EXPORT_SYMBOL_GPL(register_spu_syscalls);
172
unregister_spu_syscalls(struct spufs_calls * calls)173 void unregister_spu_syscalls(struct spufs_calls *calls)
174 {
175 BUG_ON(spufs_calls->owner != calls->owner);
176 RCU_INIT_POINTER(spufs_calls, NULL);
177 synchronize_rcu();
178 }
179 EXPORT_SYMBOL_GPL(unregister_spu_syscalls);
180
