1 /* 2 * Copyright (c) 1988 University of Utah. 3 * Copyright (c) 1991, 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 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * %sccs.include.redist.c% 11 * 12 * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$ 13 * 14 * @(#)vm_unix.c 8.2 (Berkeley) 01/09/95 15 */ 16 17 /* 18 * Traditional sbrk/grow interface to VM 19 */ 20 #include <sys/param.h> 21 #include <sys/systm.h> 22 #include <sys/proc.h> 23 #include <sys/resourcevar.h> 24 25 #include <vm/vm.h> 26 27 struct obreak_args { 28 char *nsiz; 29 }; 30 /* ARGSUSED */ 31 int 32 obreak(p, uap, retval) 33 struct proc *p; 34 struct obreak_args *uap; 35 int *retval; 36 { 37 register struct vmspace *vm = p->p_vmspace; 38 vm_offset_t new, old; 39 int rv; 40 register int diff; 41 42 old = (vm_offset_t)vm->vm_daddr; 43 new = round_page(uap->nsiz); 44 if ((int)(new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur) 45 return(ENOMEM); 46 old = round_page(old + ctob(vm->vm_dsize)); 47 diff = new - old; 48 if (diff > 0) { 49 rv = vm_allocate(&vm->vm_map, &old, diff, FALSE); 50 if (rv != KERN_SUCCESS) { 51 uprintf("sbrk: grow failed, return = %d\n", rv); 52 return(ENOMEM); 53 } 54 vm->vm_dsize += btoc(diff); 55 } else if (diff < 0) { 56 diff = -diff; 57 rv = vm_deallocate(&vm->vm_map, new, diff); 58 if (rv != KERN_SUCCESS) { 59 uprintf("sbrk: shrink failed, return = %d\n", rv); 60 return(ENOMEM); 61 } 62 vm->vm_dsize -= btoc(diff); 63 } 64 return(0); 65 } 66 67 /* 68 * Enlarge the "stack segment" to include the specified 69 * stack pointer for the process. 70 */ 71 int 72 grow(p, sp) 73 struct proc *p; 74 vm_offset_t sp; 75 { 76 register struct vmspace *vm = p->p_vmspace; 77 register int si; 78 79 /* 80 * For user defined stacks (from sendsig). 81 */ 82 if (sp < (vm_offset_t)vm->vm_maxsaddr) 83 return (0); 84 /* 85 * For common case of already allocated (from trap). 86 */ 87 if (sp >= USRSTACK - ctob(vm->vm_ssize)) 88 return (1); 89 /* 90 * Really need to check vs limit and increment stack size if ok. 91 */ 92 si = clrnd(btoc(USRSTACK-sp) - vm->vm_ssize); 93 if (vm->vm_ssize + si > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur)) 94 return (0); 95 vm->vm_ssize += si; 96 return (1); 97 } 98 99 struct ovadvise_args { 100 int anom; 101 }; 102 /* ARGSUSED */ 103 int 104 ovadvise(p, uap, retval) 105 struct proc *p; 106 struct ovadvise_args *uap; 107 int *retval; 108 { 109 110 return (EINVAL); 111 } 112