sanchayanmaity/xv6-cs450
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

map kernel instructions r/o

Browse source
This commit is contained in:
Robert Morris 2010-09-20 06:00:22 -04:00
parent 26d11ee8dc
commit a9183883b8
2 changed files with 35 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

28
usertests.c
View file

@ -1419,6 +1419,7 @@ validatetest(void)
printf(stdout, "validate ok\n");
}
// does unintialized data start out zero?
char uninit[10000];
void
bsstest(void)
@ -1434,6 +1435,32 @@ bsstest(void)
printf(stdout, "bss test ok\n");
}
// does exec do something sensible if the arguments
// are larger than a page?
void
bigargtest(void)
{
int pid, ppid;
ppid = getpid();
pid = fork();
if(pid == 0){
char *args[100];
int i;
for(i = 0; i < 99; i++)
args[i] = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
args[99] = 0;
printf(stdout, "bigarg test\n");
exec("echo", args);
printf(stdout, "bigarg test ok\n");
exit();
} else if(pid < 0){
printf(stdout, "bigargtest: fork failed\n");
exit();
}
wait();
}
int
main(int argc, char *argv[])
{
@ -1445,6 +1472,7 @@ main(int argc, char *argv[])
}
close(open("usertests.ran", O_CREATE));
// bigargtest();
bsstest();
sbrktest();
validatetest();

9
vm.c
View file

@ -125,6 +125,9 @@ pde_t*
setupkvm(void)
{
pde_t *pgdir;
extern char etext[];
char *rwstart = PGROUNDDOWN(etext) - PGSIZE;
uint rwlen = (uint)rwstart - 0x100000;
// Allocate page directory
if(!(pgdir = (pde_t *) kalloc()))
@ -132,8 +135,10 @@ setupkvm(void)
memset(pgdir, 0, PGSIZE);
if(// Map IO space from 640K to 1Mbyte
!mappages(pgdir, (void *)USERTOP, 0x60000, USERTOP, PTE_W) ||
// Map kernel and free memory pool
!mappages(pgdir, (void *)0x100000, PHYSTOP-0x100000, 0x100000, PTE_W) ||
// Map kernel instructions
!mappages(pgdir, (void *)0x100000, rwlen, 0x100000, 0) ||
// Map kernel data and free memory pool
!mappages(pgdir, rwstart, PHYSTOP-(uint)rwstart, (uint)rwstart, PTE_W) ||
// Map devices such as ioapic, lapic, ...
!mappages(pgdir, (void *)0xFE000000, 0x2000000, 0xFE000000, PTE_W))
return 0;