freebsd-dev/sys/ddb/db_watch.c
Pedro F. Giffuni 796df753f4 SPDX: Consider code from Carnegie-Mellon University.
Interesting cases, most likely from CMU Mach sources.
2017-11-30 15:48:35 +00:00

313 lines
6.7 KiB
C

/*-
* SPDX-License-Identifier: MIT-CMU
*
* Mach Operating System
* Copyright (c) 1991,1990 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
/*
* Author: Richard P. Draves, Carnegie Mellon University
* Date: 10/90
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/proc.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <ddb/ddb.h>
#include <ddb/db_watch.h>
/*
* Watchpoints.
*/
static bool db_watchpoints_inserted = true;
#define NWATCHPOINTS 100
static struct db_watchpoint db_watch_table[NWATCHPOINTS];
static db_watchpoint_t db_next_free_watchpoint = &db_watch_table[0];
static db_watchpoint_t db_free_watchpoints = 0;
static db_watchpoint_t db_watchpoint_list = 0;
static db_watchpoint_t db_watchpoint_alloc(void);
static void db_watchpoint_free(db_watchpoint_t watch);
static void db_delete_watchpoint(vm_map_t map, db_addr_t addr);
#ifdef notused
static bool db_find_watchpoint(vm_map_t map, db_addr_t addr,
db_regs_t *regs);
#endif
static void db_list_watchpoints(void);
static void db_set_watchpoint(vm_map_t map, db_addr_t addr,
vm_size_t size);
static db_watchpoint_t
db_watchpoint_alloc(void)
{
db_watchpoint_t watch;
if ((watch = db_free_watchpoints) != 0) {
db_free_watchpoints = watch->link;
return (watch);
}
if (db_next_free_watchpoint == &db_watch_table[NWATCHPOINTS]) {
db_printf("All watchpoints used.\n");
return (0);
}
watch = db_next_free_watchpoint;
db_next_free_watchpoint++;
return (watch);
}
static void
db_watchpoint_free(db_watchpoint_t watch)
{
watch->link = db_free_watchpoints;
db_free_watchpoints = watch;
}
static void
db_set_watchpoint(vm_map_t map, db_addr_t addr, vm_size_t size)
{
db_watchpoint_t watch;
if (map == NULL) {
db_printf("No map.\n");
return;
}
/*
* Should we do anything fancy with overlapping regions?
*/
for (watch = db_watchpoint_list;
watch != 0;
watch = watch->link)
if (db_map_equal(watch->map, map) &&
(watch->loaddr == addr) &&
(watch->hiaddr == addr+size)) {
db_printf("Already set.\n");
return;
}
watch = db_watchpoint_alloc();
if (watch == 0) {
db_printf("Too many watchpoints.\n");
return;
}
watch->map = map;
watch->loaddr = addr;
watch->hiaddr = addr+size;
watch->link = db_watchpoint_list;
db_watchpoint_list = watch;
db_watchpoints_inserted = false;
}
static void
db_delete_watchpoint(vm_map_t map, db_addr_t addr)
{
db_watchpoint_t watch;
db_watchpoint_t *prev;
for (prev = &db_watchpoint_list;
(watch = *prev) != 0;
prev = &watch->link)
if (db_map_equal(watch->map, map) &&
(watch->loaddr <= addr) &&
(addr < watch->hiaddr)) {
*prev = watch->link;
db_watchpoint_free(watch);
return;
}
db_printf("Not set.\n");
}
static void
db_list_watchpoints(void)
{
db_watchpoint_t watch;
if (db_watchpoint_list == 0) {
db_printf("No watchpoints set\n");
return;
}
#ifdef __LP64__
db_printf(" Map Address Size\n");
#else
db_printf(" Map Address Size\n");
#endif
for (watch = db_watchpoint_list;
watch != 0;
watch = watch->link)
#ifdef __LP64__
db_printf("%s%16p %16lx %lx\n",
#else
db_printf("%s%8p %8lx %lx\n",
#endif
db_map_current(watch->map) ? "*" : " ",
(void *)watch->map, (long)watch->loaddr,
(long)watch->hiaddr - (long)watch->loaddr);
}
/* Delete watchpoint */
/*ARGSUSED*/
void
db_deletewatch_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
char *modif)
{
db_delete_watchpoint(db_map_addr(addr), addr);
}
/* Set watchpoint */
/*ARGSUSED*/
void
db_watchpoint_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
char *modif)
{
vm_size_t size;
db_expr_t value;
if (db_expression(&value))
size = (vm_size_t) value;
else
size = 4;
db_skip_to_eol();
db_set_watchpoint(db_map_addr(addr), addr, size);
}
/*
* At least one non-optional show-command must be implemented using
* DB_SHOW_COMMAND() so that db_show_cmd_set gets created. Here is one.
*/
DB_SHOW_COMMAND(watches, db_listwatch_cmd)
{
db_list_watchpoints();
db_md_list_watchpoints();
}
void
db_set_watchpoints(void)
{
db_watchpoint_t watch;
if (!db_watchpoints_inserted) {
for (watch = db_watchpoint_list;
watch != 0;
watch = watch->link)
pmap_protect(watch->map->pmap,
trunc_page(watch->loaddr),
round_page(watch->hiaddr),
VM_PROT_READ);
db_watchpoints_inserted = true;
}
}
void
db_clear_watchpoints(void)
{
db_watchpoints_inserted = false;
}
#ifdef notused
static bool
db_find_watchpoint(vm_map_t map, db_addr_t addr, db_regs_t regs)
{
db_watchpoint_t watch;
db_watchpoint_t found = 0;
for (watch = db_watchpoint_list;
watch != 0;
watch = watch->link)
if (db_map_equal(watch->map, map)) {
if ((watch->loaddr <= addr) &&
(addr < watch->hiaddr))
return (true);
else if ((trunc_page(watch->loaddr) <= addr) &&
(addr < round_page(watch->hiaddr)))
found = watch;
}
/*
* We didn't hit exactly on a watchpoint, but we are
* in a protected region. We want to single-step
* and then re-protect.
*/
if (found) {
db_watchpoints_inserted = false;
db_single_step(regs);
}
return (false);
}
#endif
/* Delete hardware watchpoint */
/*ARGSUSED*/
void
db_deletehwatch_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
char *modif)
{
int rc;
if (count < 0)
count = 4;
rc = db_md_clr_watchpoint(addr, count);
if (rc < 0)
db_printf("hardware watchpoint could not be deleted\n");
}
/* Set hardware watchpoint */
/*ARGSUSED*/
void
db_hwatchpoint_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
char *modif)
{
int rc;
if (count < 0)
count = 4;
rc = db_md_set_watchpoint(addr, count);
if (rc < 0)
db_printf("hardware watchpoint could not be set\n");
}