xref: /linux/arch/powerpc/platforms/cell/spufs/syscalls.c (revision 498495dba268b20e8eadd7fe93c140c68b6cc9d2)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/file.h>
3 #include <linux/fs.h>
4 #include <linux/export.h>
5 #include <linux/mount.h>
6 #include <linux/namei.h>
7 #include <linux/slab.h>
8 
9 #include <linux/uaccess.h>
10 
11 #include "spufs.h"
12 
13 /**
14  * sys_spu_run - run code loaded into an SPU
15  *
16  * @unpc:    next program counter for the SPU
17  * @ustatus: status of the SPU
18  *
19  * This system call transfers the control of execution of a
20  * user space thread to an SPU. It will return when the
21  * SPU has finished executing or when it hits an error
22  * condition and it will be interrupted if a signal needs
23  * to be delivered to a handler in user space.
24  *
25  * The next program counter is set to the passed value
26  * before the SPU starts fetching code and the user space
27  * pointer gets updated with the new value when returning
28  * from kernel space.
29  *
30  * The status value returned from spu_run reflects the
31  * value of the spu_status register after the SPU has stopped.
32  *
33  */
do_spu_run(struct file * filp,__u32 __user * unpc,__u32 __user * ustatus)34 static long do_spu_run(struct file *filp,
35 			__u32 __user *unpc,
36 			__u32 __user *ustatus)
37 {
38 	long ret;
39 	struct spufs_inode_info *i;
40 	u32 npc, status;
41 
42 	ret = -EFAULT;
43 	if (get_user(npc, unpc))
44 		goto out;
45 
46 	/* check if this file was created by spu_create */
47 	ret = -EINVAL;
48 	if (filp->f_op != &spufs_context_fops)
49 		goto out;
50 
51 	i = SPUFS_I(file_inode(filp));
52 	ret = spufs_run_spu(i->i_ctx, &npc, &status);
53 
54 	if (put_user(npc, unpc))
55 		ret = -EFAULT;
56 
57 	if (ustatus && put_user(status, ustatus))
58 		ret = -EFAULT;
59 out:
60 	return ret;
61 }
62 
do_spu_create(const char __user * pathname,unsigned int flags,umode_t mode,struct file * neighbor)63 static long do_spu_create(const char __user *pathname, unsigned int flags,
64 		umode_t mode, struct file *neighbor)
65 {
66 	struct path path;
67 	struct dentry *dentry;
68 	int ret;
69 
70 	dentry = user_path_create(AT_FDCWD, pathname, &path, LOOKUP_DIRECTORY);
71 	ret = PTR_ERR(dentry);
72 	if (!IS_ERR(dentry)) {
73 		ret = spufs_create(&path, dentry, flags, mode, neighbor);
74 		done_path_create(&path, dentry);
75 	}
76 
77 	return ret;
78 }
79 
80 struct spufs_calls spufs_calls = {
81 	.create_thread = do_spu_create,
82 	.spu_run = do_spu_run,
83 	.notify_spus_active = do_notify_spus_active,
84 	.owner = THIS_MODULE,
85 #ifdef CONFIG_COREDUMP
86 	.coredump_extra_notes_size = spufs_coredump_extra_notes_size,
87 	.coredump_extra_notes_write = spufs_coredump_extra_notes_write,
88 #endif
89 };
90