arch/powerpc/platforms/cell/spufs/syscalls.c

   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  */
  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
  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 };