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This commit is contained in:
Frans Kaashoek 2011-08-09 21:49:13 -04:00
parent 832af025a3
commit 5460667c9c
1 changed files with 4 additions and 4 deletions
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8
vm.c
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@ -100,8 +100,8 @@ mappages(pde_t *pgdir, void *la, uint size, uint pa, int perm, char* (*alloc)(vo
// //
// //
// setupkvm() and exec() set up every page table like this: // setupkvm() and exec() set up every page table like this:
// 0..USERTOP : user memory (text, data, stack, heap), mapped to some phys mem // 0..USERTOP : user memory (text, data, stack, heap), mapped to some unused phys mem
// KERNBASE+640K..KERNBASE+1M: mapped to 640K..1M // KERNBASE..KERNBASE+1M: mapped to 0..1M
// KERNBASE+1M..KERNBASE+end : mapped to 1M..end // KERNBASE+1M..KERNBASE+end : mapped to 1M..end
// KERNBASE+end..KERBASE+PHYSTOP : mapped to end..PHYSTOP (free memory) // KERNBASE+end..KERBASE+PHYSTOP : mapped to end..PHYSTOP (free memory)
// 0xfe000000..0 : mapped direct (devices such as ioapic) // 0xfe000000..0 : mapped direct (devices such as ioapic)
@ -117,10 +117,10 @@ static struct kmap {
uint e; uint e;
int perm; int perm;
} kmap[] = { } kmap[] = {
{ P2V(0), 0, 1024*1024, PTE_W}, // First 1Mbyte contains BIOS and IO section { P2V(0), 0, 1024*1024, PTE_W}, // First 1Mbyte contains BIOS and some IO devices
{ (void *)KERNLINK, V2P(KERNLINK), V2P(data), 0}, // kernel text, rodata { (void *)KERNLINK, V2P(KERNLINK), V2P(data), 0}, // kernel text, rodata
{ data, V2P(data), PHYSTOP, PTE_W}, // kernel data, memory { data, V2P(data), PHYSTOP, PTE_W}, // kernel data, memory
{ (void*)DEVSPACE, DEVSPACE, 0, PTE_W}, // device mappings { (void*)DEVSPACE, DEVSPACE, 0, PTE_W}, // more devices
}; };
// Set up kernel part of a page table. // Set up kernel part of a page table.