Change address reporting to fit the grading script's standards.

This commit is contained in:
Danila Fedorin 2019-04-23 20:46:11 -07:00
parent 8cd1daf8dd
commit 0fe97e52c3
1 changed files with 3 additions and 1 deletions

View File

@ -563,13 +563,14 @@ int
user_mem_check(struct Env *env, const void *va, size_t len, int perm)
{
// LAB 3: Your code here.
uintptr_t to_report = (uintptr_t) va;
const char* bottom = ROUNDDOWN(va, PGSIZE);
size_t aligned_count = ROUNDUP(len, PGSIZE) / PGSIZE;
pde_t mask = PTE_P | PTE_U | PTE_W;
pde_t perms = mask;
#define VALID ((perms & (perm | PTE_P)) == (perm | PTE_P))
#define DO_CHECK if(!VALID) { user_mem_check_addr = (uintptr_t) bottom; return -E_FAULT; }
#define DO_CHECK if(!VALID) { user_mem_check_addr = to_report; return -E_FAULT; }
while(aligned_count--) {
perms &= env->env_pgdir[PDX(bottom)] & mask;
@ -577,6 +578,7 @@ user_mem_check(struct Env *env, const void *va, size_t len, int perm)
perms &= (*pgdir_walk(env->env_pgdir, bottom, 0)) & mask;
DO_CHECK;
bottom += PGSIZE;
to_report = (uintptr_t) bottom;
}
return 0;