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

   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|
  73                                 LOOKUP_OPEN|LOOKUP_CREATE, &nd);
  74                 if (!ret) {
  75                         ret = spufs_create(&nd, flags, mode, neighbor);
  76                         path_release(&nd);
  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 };