MPROTECT

NAME

SYNOPSIS

#include <sys/mman.h>

mprotect(addr, len, prot)
caddr_t addr;
int len, prot;

DESCRIPTION

mprotect() changes the access protections on the mappings specified by the range [addr, addr + len) to be that specified by prot. Legitimate values for prot are PROT_READ and (PROT_WRITE | PROT_READ).  

RETURN VALUE

mprotect() returns 0 on success, -1 on failure.  

ERRORS

EINVAL

addr is not a multiple of the page size as returned by getpagesize(2).

ENOMEM

Addresses in the range [addr, addr + len) are not in the data section of a process.

SEE ALSO

---End File /usr/man/man2/mprotect.2---

You need to compile the following and add it to /lib/libc.a

Inserting file /usr/src/lib/libc/hp300/sys/mprotect.c ---Begin File /usr/src/lib/libc/hp300/sys/mprotect.c--- #ifdef SYSLIBC_SCCS _sccsid:.asciz  "@(#)mprotect.c"
#endif SYSLIBC_SCCS

#include "SYS.h"

SYSCALL(mprotect)         rts
---End File /usr/src/lib/libc/hp300/sys/mprotect.c---

*** hp300/machdep.c.orig        Tue Aug 29 13:09:56 1989
--- hp300/machdep.c     Mon Dec 11 17:07:18 1989
*************** *** 560,566 ****
  #endif
        sigf.sf_signum = sig;

        sigf.sf_code = 0;
!       if (sig == SIGILL || sig == SIGFPE) {

                sigf.sf_code = u.u_code;

                u.u_code = 0;

        }
--- 560,566 ----
  #endif
        sigf.sf_signum = sig;

        sigf.sf_code = 0;
!       if (sig == SIGILL || sig == SIGFPE || sig == SIGBUS) {

                sigf.sf_code = u.u_code;

                u.u_code = 0;

        }
*** sys/kern_mman.c.orig        Tue Aug 29 13:16:29 1989
--- sys/kern_mman.c     Thu Dec 14 10:07:39 1989
*************** *** 249,257 ****
        u.u_pofile[fd] &= ~UF_MAPPED;

  }
  
  mprotect() ! {
  
  }
  
  madvise() --- 249,296 ----
        u.u_pofile[fd] &= ~UF_MAPPED;

  }
   +
  mprotect() ! {     struct a {
!               caddr_t addr;
!               int     len;
!               int     prot;
!       } *uap = (struct a *)u.u_ap;
!       int fv,off;
!       int tprot;
!       register struct pte *pte;
!       struct cmap *c;
!       int s;

   +       u.u_r.r_val1 = -1;
+ +       if ((uap->len < 0 ||
+        (int)uap->addr & CLOFSET)) {
+        u.u_error = EINVAL;
+        return;
+       }
+ + +       if ((uap->prot & PROT_WRITE) == 0)
+        tprot= PG_RO;
+       else tprot=PG_RW;
+       /* check the pages are in data section */
+       if (!(isadsv(u.u_procp, btoc(uap->addr))
+ &&isadsv(u.u_procp ,btoc(uap->addr+uap->len) -1))) +        { u.u_error = ENOMEM;
+               return;}
+               
+ +       fv = btop(uap->addr);
+       pte = vtopte(u.u_procp, fv);
+       for (off = 0; off < uap->len; off += NBPG) {
+       
+        *(u_int *)pte &= ~PG_PROT;
+        *(u_int *)pte |= tprot;
+        pte++;}
+ +       newptes(vtopte(u.u_procp, fv), fv, btoc(uap->len));
+       u.u_r.r_val1 = 0;

  }
  
  madvise() *** hp300/trap.c.orig   Tue Aug 29 13:09:59 1989
--- hp300/trap.c        Mon Dec 11 17:48:59 1989
*************** *** 112,117 **** --- 112,118 ----
  
        case T_BUSERR+USER:     /* bus error */

        case T_ADDRERR+USER:    /* address error */
+               u.u_code=v;

                i = SIGBUS;

                break;

   *************** *** 293,298 **** --- 294,300 ----
                                        printf("PTF|WPF...);

                                        if (type == T_MMUFLT)

                                                goto copyfault;
+                                       u.u_code=v;

                                        i = SIGBUS;

                                        break;

                                }
*************** *** 346,351 **** --- 348,354 ----
  #endif
                        if (type == T_MMUFLT)

                                goto copyfault;
+                       u.u_code=v;

                        i = SIGBUS;

                        break;

                }

Index

NAME

SYNOPSIS

DESCRIPTION

RETURN VALUE

ERRORS

SEE ALSO