From b3cfd7fc372424d754f5478c93f6fbe756d9c80f Mon Sep 17 00:00:00 2001 From: Austin Clements Date: Thu, 2 Sep 2010 15:18:19 -0400 Subject: [PATCH] Simplify freevm using deallocuvm --- vm.c | 25 ++++++------------------- 1 file changed, 6 insertions(+), 19 deletions(-) diff --git a/vm.c b/vm.c index 8cfac14..12aebe5 100644 --- a/vm.c +++ b/vm.c @@ -206,8 +206,7 @@ allocuvm(pde_t *pgdir, char *addr, uint sz) return 1; } -// deallocate some of the user pages, in response to sbrk() -// with a negative argument. if addr is not page-aligned, +// deallocate some of the user pages. if addr is not page-aligned, // then only deallocates starting at the next page boundary. int deallocuvm(pde_t *pgdir, char *addr, uint sz) @@ -235,26 +234,14 @@ deallocuvm(pde_t *pgdir, char *addr, uint sz) void freevm(pde_t *pgdir) { - uint i, j, da; + uint i; if(!pgdir) - panic("freevm: no pgdir\n"); + panic("freevm: no pgdir"); + deallocuvm(pgdir, 0, USERTOP); for(i = 0; i < NPDENTRIES; i++){ - da = PTE_ADDR(pgdir[i]); - if(da != 0){ - pte_t *pgtab = (pte_t*) da; - for(j = 0; j < NPTENTRIES; j++){ - if(pgtab[j] != 0){ - uint pa = PTE_ADDR(pgtab[j]); - uint va = PGADDR(i, j, 0); - if(va < USERTOP) // user memory - kfree((void *) pa); - pgtab[j] = 0; - } - } - kfree((void *) da); - pgdir[i] = 0; - } + if(pgdir[i] & PTE_P) + kfree((void *) PTE_ADDR(pgdir[i])); } kfree((void *) pgdir); }