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 */
34static 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;
59out:
60	return ret;
61}
62
63static 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
80struct 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