release/src-rt-6.x/linux/linux-2.6/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(filp, 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 #ifndef MODULE
  62 asmlinkage long sys_spu_run(int fd, __u32 __user *unpc, __u32 __user *ustatus)
  63 {
  64         int fput_needed;
  65         struct file *filp;
  66         long ret;
  67
  68         ret = -EBADF;
  69         filp = fget_light(fd, &fput_needed);
  70         if (filp) {
  71                 ret = do_spu_run(filp, unpc, ustatus);
  72                 fput_light(filp, fput_needed);
  73         }
  74
  75         return ret;
  76 }
  77 #endif
  78
  79 asmlinkage long sys_spu_create(const char __user *pathname,
  80                                         unsigned int flags, mode_t mode)
  81 {
  82         char *tmp;
  83         int ret;
  84
  85         tmp = getname(pathname);
  86         ret = PTR_ERR(tmp);
  87         if (!IS_ERR(tmp)) {
  88                 struct nameidata nd;
  89
  90                 ret = path_lookup(tmp, LOOKUP_PARENT|
  91                                 LOOKUP_OPEN|LOOKUP_CREATE, &nd);
  92                 if (!ret) {
  93                         ret = spufs_create(&nd, flags, mode);
  94                         path_release(&nd);
  95                 }
  96                 putname(tmp);
  97         }
  98
  99         return ret;
 100 }
 101
 102 struct spufs_calls spufs_calls = {
 103         .create_thread = sys_spu_create,
 104         .spu_run = do_spu_run,
 105         .owner = THIS_MODULE,
 106 };