sys/vfs/procfs/procfs_regs.c

   1 /*
   2  * Copyright (c) 1993 Jan-Simon Pendry
   3  * Copyright (c) 1993
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * This code is derived from software contributed to Berkeley by
   7  * Jan-Simon Pendry.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)procfs_regs.c       8.4 (Berkeley) 6/15/94
  34  *
  35  * From:
  36  * $FreeBSD: src/sys/miscfs/procfs/procfs_regs.c,v 1.10.2.3 2002/01/22 17:22:59 nectar Exp $
  37  * $DragonFly: src/sys/vfs/procfs/procfs_regs.c,v 1.11 2007/02/19 01:14:24 corecode Exp $
  38  */
  39
  40 #include <sys/param.h>
  41 #include <sys/proc.h>
  42 #include <sys/priv.h>
  43 #include <sys/vnode.h>
  44 #include <sys/reg.h>
  45 #include <vfs/procfs/procfs.h>
  46 #include <vm/vm.h>
  47 #include <vm/vm_extern.h>
  48
  49 int
  50 procfs_doregs(struct proc *curp, struct lwp *lp, struct pfsnode *pfs,
  51               struct uio *uio)
  52 {
  53         struct proc *p = lp->lwp_proc;
  54         int error;
  55         struct reg r;
  56
  57         /* Can't trace a process that's currently exec'ing. */
  58         if ((p->p_flags & P_INEXEC) != 0)
  59                 return EAGAIN;
  60         if (!CHECKIO(curp, p) || p_trespass(curp->p_ucred, p->p_ucred))
  61                 return EPERM;
  62
  63         LWPHOLD(lp);
  64         error = procfs_read_regs(lp, &r);
  65         if (error == 0)
  66                 error = uiomove_frombuf(&r, sizeof(r), uio);
  67         if (error == 0 && uio->uio_rw == UIO_WRITE) {
  68                 if (p->p_stat != SSTOP)
  69                         error = EBUSY;
  70                 else
  71                         error = procfs_write_regs(lp, &r);
  72         }
  73         LWPRELE(lp);
  74         uio->uio_offset = 0;
  75
  76         return (error);
  77 }
  78
  79 int
  80 procfs_validregs(struct lwp *lp)
  81 {
  82         return ((lp->lwp_proc->p_flags & P_SYSTEM) == 0);
  83 }