phys addr arg of 0 must be possible for pt_writemap too (instead of meaning

unmap).

diff --git a/servers/vm/i386/pagetable.c b/servers/vm/i386/pagetable.c
index bda5f5c4cfefb515fc7604d2bc2ffd001c46fc88..5c421f4719fca281b49014f90ecc3041156a135e 100644 (file)
--- a/servers/vm/i386/pagetable.c
+++ b/servers/vm/i386/pagetable.c
@@ -206,7 +206,7 @@ PRIVATE void vm_freepages(vir_bytes vir, vir_bytes phys, int pages, int reason)
                FREE_MEM(ABS2CLICK(phys), pages);
                if(pt_writemap(&vmp->vm_pt,
                        vir + CLICK2ABS(vmp->vm_arch.vm_seg[D].mem_phys),
-                       0, pages*I386_PAGE_SIZE, 0, WMF_OVERWRITE) != OK)
+                       MAP_NONE, pages*I386_PAGE_SIZE, 0, WMF_OVERWRITE) != OK)
                                vm_panic("vm_freepages: pt_writemap failed",
                                        NO_NUM);
        } else {
@@ -378,11 +378,15 @@ PUBLIC int pt_writemap(pt_t *pt, vir_bytes v, phys_bytes physaddr,
 
        pages = bytes / I386_PAGE_SIZE;
 
+       /* MAP_NONE means to clear the mapping. It doesn't matter
+        * what's actually written into the PTE if I386_VM_PRESENT
+        * isn't on, so we can just write MAP_NONE into it.
+        */
 #if SANITYCHECKS
-       if(physaddr && !(flags & I386_VM_PRESENT)) {
+       if(physaddr != MAP_NONE && !(flags & I386_VM_PRESENT)) {
                vm_panic("pt_writemap: writing dir with !P\n", NO_NUM);
        }
-       if(!physaddr && flags) {
+       if(physaddr == MAP_NONE && flags) {
                vm_panic("pt_writemap: writing 0 with flags\n", NO_NUM);
        }
 #endif
@@ -901,7 +905,7 @@ PUBLIC int pt_copy(pt_t *src, pt_t *dst)
 
 #define PHYSMAGIC 0x7b9a0590
 
-#define PHYS_UNMAP if(OK != pt_writemap(&vmp->vm_pt, varmap_loc, 0,    \
+#define PHYS_UNMAP if(OK != pt_writemap(&vmp->vm_pt, varmap_loc, MAP_NONE,\
        I386_PAGE_SIZE, 0, WMF_OVERWRITE)) {                            \
                vm_panic("PHYS_UNMAP: pt_writemap failed", NO_NUM); }
 

diff --git a/servers/vm/region.c b/servers/vm/region.c
index 1d2cda45daa6d6df798156e6570724315f296a1e..358996db8a06c575e87cb9f8fc67bef10c26dda1 100644 (file)
--- a/servers/vm/region.c
+++ b/servers/vm/region.c
@@ -932,7 +932,7 @@ PUBLIC int map_unmap_region(struct vmproc *vmp, struct vir_region *region)
        SANITYCHECK(SCL_DETAIL);
 
        if(pt_writemap(&vmp->vm_pt, r->vaddr,
-         0, r->length, 0, WMF_OVERWRITE) != OK) {
+         MAP_NONE, r->length, 0, WMF_OVERWRITE) != OK) {
            printf("VM: map_unmap_region: pt_writemap failed\n");
            return ENOMEM;
        }