Module Name: src
Committed By: reinoud
Date: Mon Aug 29 14:59:09 UTC 2011
Modified Files:
src/sys/arch/usermode/usermode: pmap.c trap.c
Log Message:
Implement read and modify detection code
To generate a diff of this commit:
cvs rdiff -u -r1.38 -r1.39 src/sys/arch/usermode/usermode/pmap.c
cvs rdiff -u -r1.12 -r1.13 src/sys/arch/usermode/usermode/trap.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/usermode/usermode/pmap.c
diff -u src/sys/arch/usermode/usermode/pmap.c:1.38 src/sys/arch/usermode/usermode/pmap.c:1.39
--- src/sys/arch/usermode/usermode/pmap.c:1.38 Sat Aug 27 17:59:24 2011
+++ src/sys/arch/usermode/usermode/pmap.c Mon Aug 29 14:59:09 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.c,v 1.38 2011/08/27 17:59:24 reinoud Exp $ */
+/* $NetBSD: pmap.c,v 1.39 2011/08/29 14:59:09 reinoud Exp $ */
/*-
* Copyright (c) 2011 Reinoud Zandijk <rein...@netbsd.org>
@@ -27,7 +27,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.38 2011/08/27 17:59:24 reinoud Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.39 2011/08/29 14:59:09 reinoud Exp $");
#include "opt_memsize.h"
#include "opt_kmempages.h"
@@ -90,6 +90,8 @@
static void pv_update(struct pv_entry *pv);
static void pmap_update_page(uintptr_t ppn);
+void pmap_get_current_protection(pmap_t pmap, vaddr_t va,
+ vm_prot_t *cur_prot, vm_prot_t *prot);
static struct pv_entry *pv_get(pmap_t pmap, uintptr_t ppn, uintptr_t lpn);
static struct pv_entry *pv_alloc(void);
static void pv_free(struct pv_entry *pv);
@@ -421,6 +423,39 @@
return pv;
}
+void
+pmap_get_current_protection(pmap_t pmap, vaddr_t va,
+ vm_prot_t *cur_prot, vm_prot_t *prot)
+{
+ struct pv_entry *pv;
+
+ uintptr_t lpn;
+
+ aprint_debug("pmap_get_current_protection pmap %p, va %p\n", pmap, (void *) va);
+#ifdef DIAGNOSTIC
+ if ((va < VM_MIN_ADDRESS) || (va >= VM_MAX_ADDRESS))
+ panic("pmap_do_enter: invalid va isued\n");
+#endif
+
+ lpn = atop(va - VM_MIN_ADDRESS); /* V->L */
+
+ /* raise interupt level */
+ pv = pmap->pm_entries[lpn];
+ if (pv == NULL) {
+ *cur_prot = *prot = VM_PROT_NONE;
+ return;
+ }
+
+ *prot = pv->pv_prot;
+ *cur_prot = VM_PROT_NONE;
+ if (pv->pv_mmap_ppl & PROT_READ)
+ *cur_prot |= VM_PROT_READ;
+ if (pv->pv_mmap_ppl & PROT_WRITE)
+ *cur_prot |= VM_PROT_WRITE;
+ if (pv->pv_mmap_ppl & PROT_EXEC)
+ *cur_prot |= VM_PROT_EXECUTE;
+}
+
static void
pmap_page_activate(struct pv_entry *pv)
{
@@ -660,6 +695,10 @@
/* TODO protect against roque values */
aprint_debug("pmap_extract: extracting va %p\n", (void *) va);
+#ifdef DIAGNOSTIC
+ if ((va < VM_MIN_ADDRESS) || (va > VM_MAX_ADDRESS))
+ panic("pmap_extract: invalid va isued\n");
+#endif
pv = pmap->pm_entries[atop(va - VM_MIN_ADDRESS)]; /* V->L */
if (pv == NULL)
Index: src/sys/arch/usermode/usermode/trap.c
diff -u src/sys/arch/usermode/usermode/trap.c:1.12 src/sys/arch/usermode/usermode/trap.c:1.13
--- src/sys/arch/usermode/usermode/trap.c:1.12 Mon Aug 29 13:15:54 2011
+++ src/sys/arch/usermode/usermode/trap.c Mon Aug 29 14:59:09 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: trap.c,v 1.12 2011/08/29 13:15:54 jmcneill Exp $ */
+/* $NetBSD: trap.c,v 1.13 2011/08/29 14:59:09 reinoud Exp $ */
/*-
* Copyright (c) 2011 Reinoud Zandijk <rein...@netbsd.org>
@@ -27,7 +27,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.12 2011/08/29 13:15:54 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.13 2011/08/29 14:59:09 reinoud Exp $");
#include <sys/types.h>
#include <sys/param.h>
@@ -49,11 +49,12 @@
//#include <machine/userret.h>
+/* forwards and externals */
void setup_signal_handlers(void);
static void mem_access_handler(int sig, siginfo_t *info, void *ctx);
-
-static struct sigaction sa;
+extern void pmap_get_current_protection(pmap_t pmap, vaddr_t va,
+ vm_prot_t *cur_prot, vm_prot_t *prot);
extern int errno;
void
@@ -64,6 +65,8 @@
void
setup_signal_handlers(void)
{
+ static struct sigaction sa;
+
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART | SA_SIGINFO;
sa.sa_sigaction = mem_access_handler;
@@ -84,7 +87,7 @@
struct vmspace *vm;
struct vm_map *vm_map;
struct trapframe *tf;
- vm_prot_t atype;
+ vm_prot_t cur_prot, prot, atype;
vaddr_t va;
vaddr_t onfault;
int kmem, rv;
@@ -104,7 +107,7 @@
onfault = (vaddr_t) pcb->pcb_onfault;
vm = p->p_vmspace;
-#if 0
+#if 1
printf("SIGSEGV or SIGBUS!\n");
printf("\tsi_signo = %d\n", info->si_signo);
printf("\tsi_errno = %d\n", info->si_errno);
@@ -141,17 +144,39 @@
panic("peeing outside the box!");
}
- /* XXX TODO determine atype?? */
-atype = PROT_READ;
-again:
- pcb->pcb_onfault = NULL;
- rv = uvm_fault(vm_map, (vaddr_t) va, atype);
- pcb->pcb_onfault = (void *) onfault;
-if (rv) printf("uvm_fault rv = %d\n", rv);
-if (rv == EACCES) {
- atype |= PROT_WRITE | PROT_EXEC;
- goto again;
-}
+ /* determine accesstype */
+ pmap_get_current_protection(vm_map->pmap, va, &cur_prot, &prot);
+ rv = 0;
+ if ((prot == VM_PROT_NONE) && (cur_prot == VM_PROT_NONE)) {
+ /* not mapped in yet */
+printf("was not mapped in yet --> faulting read first\n");
+ pcb->pcb_onfault = NULL;
+ rv = uvm_fault(vm_map, (vaddr_t) va, VM_PROT_READ);
+ pcb->pcb_onfault = (void *) onfault;
+
+ /* update accesstypes */
+ pmap_get_current_protection(vm_map->pmap, va, &cur_prot, &prot);
+ }
+
+ /* if no error, its map-able */
+ if (rv == 0) {
+ atype = VM_PROT_NONE; /* assume read */
+ if (prot & PROT_EXEC)
+ atype |= VM_PROT_EXECUTE; /* could well be execute */
+ if ((prot & PROT_WRITE) && (cur_prot & VM_PROT_READ))
+ atype = VM_PROT_WRITE; /* if it had write access */
+
+printf("%sva %p, prot = %d, cur_prot = %d ==> atype = %d\n", kmem?"kmem, ":"", (void *) va, prot, cur_prot, atype);
+ if (atype != VM_PROT_NONE) {
+ pcb->pcb_onfault = NULL;
+ rv = uvm_fault(vm_map, (vaddr_t) va, atype);
+ pcb->pcb_onfault = (void *) onfault;
+ }
+ }
+
+ if (rv)
+ aprint_debug("uvm_fault returned error %d\n", rv);
+
if (rv) {
/* something got wrong */
if (kmem) {
