xref: /linux/arch/powerpc/platforms/cell/spufs/syscalls.c (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
1 #include <linux/file.h>
2 #include <linux/fs.h>
3 #include <linux/module.h>
4 #include <linux/mount.h>
5 #include <linux/namei.h>
6 
7 #include <asm/uaccess.h>
8 
9 #include "spufs.h"
10 
11 /**
12  * sys_spu_run - run code loaded into an SPU
13  *
14  * @unpc:    next program counter for the SPU
15  * @ustatus: status of the SPU
16  *
17  * This system call transfers the control of execution of a
18  * user space thread to an SPU. It will return when the
19  * SPU has finished executing or when it hits an error
20  * condition and it will be interrupted if a signal needs
21  * to be delivered to a handler in user space.
22  *
23  * The next program counter is set to the passed value
24  * before the SPU starts fetching code and the user space
25  * pointer gets updated with the new value when returning
26  * from kernel space.
27  *
28  * The status value returned from spu_run reflects the
29  * value of the spu_status register after the SPU has stopped.
30  *
31  */
32 static long do_spu_run(struct file *filp,
33 			__u32 __user *unpc,
34 			__u32 __user *ustatus)
35 {
36 	long ret;
37 	struct spufs_inode_info *i;
38 	u32 npc, status;
39 
40 	ret = -EFAULT;
41 	if (get_user(npc, unpc) || get_user(status, ustatus))
42 		goto out;
43 
44 	/* check if this file was created by spu_create */
45 	ret = -EINVAL;
46 	if (filp->f_op != &spufs_context_fops)
47 		goto out;
48 
49 	i = SPUFS_I(filp->f_dentry->d_inode);
50 	ret = spufs_run_spu(filp, i->i_ctx, &npc, &status);
51 
52 	if (put_user(npc, unpc) || put_user(status, ustatus))
53 		ret = -EFAULT;
54 out:
55 	return ret;
56 }
57 
58 #ifndef MODULE
59 asmlinkage long sys_spu_run(int fd, __u32 __user *unpc, __u32 __user *ustatus)
60 {
61 	int fput_needed;
62 	struct file *filp;
63 	long ret;
64 
65 	ret = -EBADF;
66 	filp = fget_light(fd, &fput_needed);
67 	if (filp) {
68 		ret = do_spu_run(filp, unpc, ustatus);
69 		fput_light(filp, fput_needed);
70 	}
71 
72 	return ret;
73 }
74 #endif
75 
76 asmlinkage long sys_spu_create(const char __user *pathname,
77 					unsigned int flags, mode_t mode)
78 {
79 	char *tmp;
80 	int ret;
81 
82 	tmp = getname(pathname);
83 	ret = PTR_ERR(tmp);
84 	if (!IS_ERR(tmp)) {
85 		struct nameidata nd;
86 
87 		ret = path_lookup(tmp, LOOKUP_PARENT|
88 				LOOKUP_OPEN|LOOKUP_CREATE, &nd);
89 		if (!ret) {
90 			ret = spufs_create_thread(&nd, flags, mode);
91 			path_release(&nd);
92 		}
93 		putname(tmp);
94 	}
95 
96 	return ret;
97 }
98 
99 struct spufs_calls spufs_calls = {
100 	.create_thread = sys_spu_create,
101 	.spu_run = do_spu_run,
102 	.owner = THIS_MODULE,
103 };
104