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))
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_path.dentry->d_inode);
50 	ret = spufs_run_spu(i->i_ctx, &npc, &status);
51 
52 	if (put_user(npc, unpc))
53 		ret = -EFAULT;
54 
55 	if (ustatus && put_user(status, ustatus))
56 		ret = -EFAULT;
57 out:
58 	return ret;
59 }
60 
61 static long do_spu_create(const char __user *pathname, unsigned int flags,
62 		mode_t mode, struct file *neighbor)
63 {
64 	char *tmp;
65 	int ret;
66 
67 	tmp = getname(pathname);
68 	ret = PTR_ERR(tmp);
69 	if (!IS_ERR(tmp)) {
70 		struct nameidata nd;
71 
72 		ret = path_lookup(tmp, LOOKUP_PARENT, &nd);
73 		if (!ret) {
74 			nd.flags |= LOOKUP_OPEN | LOOKUP_CREATE;
75 			ret = spufs_create(&nd, flags, mode, neighbor);
76 			path_put(&nd.path);
77 		}
78 		putname(tmp);
79 	}
80 
81 	return ret;
82 }
83 
84 struct spufs_calls spufs_calls = {
85 	.create_thread = do_spu_create,
86 	.spu_run = do_spu_run,
87 	.coredump_extra_notes_size = spufs_coredump_extra_notes_size,
88 	.coredump_extra_notes_write = spufs_coredump_extra_notes_write,
89 	.notify_spus_active = do_notify_spus_active,
90 	.owner = THIS_MODULE,
91 };
92