sys/uvm/uvm_unix.c

/*	$Id: uvm_unix.c,v 1.1 1998/02/05 06:25:08 mrg Exp $	*/

/*
 * XXXCDC: "ROUGH DRAFT" QUALITY UVM PRE-RELEASE FILE!
 *         >>>USE AT YOUR OWN RISK, WORK IS NOT FINISHED<<<
 */
/*
 * Copyright (c) 1997 Charles D. Cranor and Washington University.
 * Copyright (c) 1991, 1993 The Regents of the University of California.
 * Copyright (c) 1988 University of Utah.
 *
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Charles D. Cranor,
 *	Washington University, the University of California, Berkeley and
 *	its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$
 *
 *      @(#)vm_unix.c   8.1 (Berkeley) 6/11/93
 */

/*
 * uvm_unix.c: traditional sbrk/grow interface to vm.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/vnode.h>
#include <sys/core.h>

#include <sys/mount.h>
#include <sys/syscallargs.h>

#include <vm/vm.h>
#include <uvm/uvm.h>


/*
 * sys_obreak: set break
 */

int sys_obreak(p, v, retval)

struct proc *p;
void *v;
register_t *retval;
{
  struct sys_obreak_args /* {
			    syscallarg(char *) nsize;
			    } */ *uap = v;
  register struct vmspace *vm = p->p_vmspace;
  vm_offset_t new, old;
  int rv;
  register int diff;

  old = (vm_offset_t)vm->vm_daddr;
  new = round_page(SCARG(uap, nsize));
  if ((int)(new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur)
    return(ENOMEM);

  old = round_page(old + ctob(vm->vm_dsize));
  diff = new - old;

  /*
   * grow or shrink?
   */

  if (diff > 0) {

    rv = uvm_map(&vm->vm_map, &old, diff, NULL, UVM_UNKNOWN_OFFSET,
           UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY, UVM_ADV_NORMAL,
           UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW));

    if (rv != KERN_SUCCESS) {
      uprintf("sbrk: grow failed, return = %d\n", rv);
      return(ENOMEM);
    }
    vm->vm_dsize += btoc(diff);

  } else if (diff < 0) {

    diff = -diff;
    rv = uvm_deallocate(&vm->vm_map, new, diff);
    if (rv != KERN_SUCCESS) {
      uprintf("sbrk: shrink failed, return = %d\n", rv);
      return(ENOMEM);
    }
    vm->vm_dsize -= btoc(diff);

  }
  return(0);
}

/*
 * uvm_grow: enlarge the "stack segment" to include sp.
 */

int uvm_grow(p, sp)

struct proc *p;
vm_offset_t sp;

{
  register struct vmspace *vm = p->p_vmspace;
  register int si;

  /*
   * For user defined stacks (from sendsig).
   */
  if (sp < (vm_offset_t)vm->vm_maxsaddr)
    return (0);

  /*
   * For common case of already allocated (from trap).
   */
  if (sp >= USRSTACK - ctob(vm->vm_ssize))
    return (1);

  /*
   * Really need to check vs limit and increment stack size if ok.
   */
  si = clrnd(btoc(USRSTACK-sp) - vm->vm_ssize);
  if (vm->vm_ssize + si > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur))
    return (0);
  vm->vm_ssize += si;
  return (1);
}

/*
 * sys_oadvise: old advice system call
 */

/* ARGSUSED */
int sys_ovadvise(p, v, retval)

struct proc *p;
void *v;
register_t *retval;

{
#if 0
  struct sys_ovadvise_args /* {
			      syscallarg(int) anom;
			      } */ *uap = v;
#endif
  return (EINVAL);
}

/*
 * uvm_coredump: dump core!
 */

int uvm_coredump(p, vp, cred, chdr)

struct proc *p;
struct vnode *vp;
struct ucred *cred;
struct core *chdr;

{
  register struct vmspace *vm = p->p_vmspace;
  register vm_map_t map = &vm->vm_map;
  register vm_map_entry_t entry;
  vm_offset_t start, end;
  struct coreseg cseg;
  off_t offset;
  int flag, error = 0;

  if (!map->is_main_map) {
#ifdef DEBUG
    uprintf(
     "uvm_coredump: %s map 0x%lx: pmap=0x%lx,ref=%d,nentries=%d,version=%d\n",
     (map->is_main_map ? "Task" : "Share"),
     (long)map, (long)(map->pmap),
     map->ref_count, map->nentries,
     map->timestamp);
#endif
    return EIO;
  }

  offset = chdr->c_hdrsize + chdr->c_seghdrsize + chdr->c_cpusize;

  for (entry = map->header.next; entry != &map->header;
       entry = entry->next) {

    if (UVM_ET_ISMAP(entry)) {
#ifdef DEBUG
      uprintf("uvm_coredump: entry: share=0x%lx, offset=0x%lx\n",
	      (long) entry->object.share_map,
	      (long) entry->offset);
#endif
      continue;
    }

    if (!(entry->protection & VM_PROT_WRITE))
      continue;

    start = entry->start;
    end = entry->end;

    if (start >= VM_MAXUSER_ADDRESS)
      continue;

    if (end > VM_MAXUSER_ADDRESS)
      end = VM_MAXUSER_ADDRESS;

    if (start >= (vm_offset_t)vm->vm_maxsaddr) {
      flag = CORE_STACK;
      start = trunc_page(USRSTACK - ctob(vm->vm_ssize));
      if (start >= end)
	continue;
    } else
      flag = CORE_DATA;

    /*
     * Set up a new core file segment.
     */
    CORE_SETMAGIC(cseg, CORESEGMAGIC, CORE_GETMID(*chdr), flag);
    cseg.c_addr = start;
    cseg.c_size = end - start;

    error = vn_rdwr(UIO_WRITE, vp,
		    (caddr_t)&cseg, chdr->c_seghdrsize,
		    offset, UIO_SYSSPACE,
		    IO_NODELOCKED|IO_UNIT, cred, (int *) NULL, p);
    if (error)
      break;

    offset += chdr->c_seghdrsize;
    error = vn_rdwr(UIO_WRITE, vp,
		    (caddr_t)cseg.c_addr, (int)cseg.c_size,
		    offset, UIO_USERSPACE,
		    IO_NODELOCKED|IO_UNIT, cred, (int *) NULL, p);
    if (error)
      break;

    offset += cseg.c_size;
    chdr->c_nseg++;
  }

  return error;
}