/**
* \brief Reset kernel paging.
*
* This function resets the page maps for kernel and memory-space. It clears out
* all other mappings. Use this only at system bootup!
*/
void paging_x86_32_reset(void)
{
// Re-map physical memory
// XXX: Map in what we get from Multiboot. We should actually map
// stuff dynamically, whenever raw mem gets retyped into a kernel
// object
/* if(paging_map_memory(0, multiboot_info->mem_upper * 1024 + 0x100000) */
lpaddr_t lpaddr = gen_phys_to_local_phys(X86_32_PADDR_SPACE_LIMIT -
X86_32_DEVICE_SPACE_LIMIT);
if(paging_x86_32_map_memory(0, lpaddr) != 0) {
panic("error while mapping physical memory!");
}
// Switch to new page layout
#ifdef CONFIG_PAE
paging_x86_32_context_switch(mem_to_local_phys((lvaddr_t)pdpte));
#else
paging_x86_32_context_switch(mem_to_local_phys((lvaddr_t)pdir));
#endif
}
/// Map within a x86_32 pdpt
static errval_t x86_32_pdpt(struct capability *dest, cslot_t slot,
struct capability * src, uintptr_t flags,
uintptr_t offset, uintptr_t pte_count,
struct cte *mapping_cte)
{
if (slot >= X86_32_PTABLE_SIZE) { // Slot within page table
return SYS_ERR_VNODE_SLOT_INVALID;
}
if (pte_count > 1) { // disallow multiple pdpt mappings at a time
return SYS_ERR_VM_MAP_SIZE;
}
if (src->type != ObjType_VNode_x86_32_pdir) { // Right mapping
return SYS_ERR_WRONG_MAPPING;
}
if(slot >= X86_32_PDPTE_BASE(X86_32_MEMORY_OFFSET)) { // Kernel mapped here
return SYS_ERR_VNODE_SLOT_RESERVED;
}
// Destination
genpaddr_t dest_gp = dest->u.vnode_x86_32_pdpt.base;
lpaddr_t dest_lp = gen_phys_to_local_phys(dest_gp);
lvaddr_t dest_lv = local_phys_to_mem(dest_lp);
union x86_32_pdpte_entry *entry =
(union x86_32_pdpte_entry *)dest_lv + slot;
// Set metadata
create_mapping_cap(mapping_cte, src,
dest_lp + slot * sizeof(union x86_32_pdpte_entry),
pte_count);
// Source
genpaddr_t src_gp = src->u.vnode_x86_32_pdir.base;
lpaddr_t src_lp = gen_phys_to_local_phys(src_gp);
paging_x86_32_map_pdpte(entry, src_lp);
paging_x86_32_context_switch(dcb_current->vspace); // To flush TLB
return SYS_ERR_OK;
}
static void init_page_tables(struct spawn_state *st, alloc_phys_func alloc_phys)
{
/* Allocate memory for init's page tables */
#ifdef CONFIG_PAE
init_pdpte = (void *)local_phys_to_mem(alloc_phys(X86_32_PDPTE_SIZE
* sizeof(union x86_32_pdpte_entry)));
#endif
init_pdir = (void *)local_phys_to_mem(
alloc_phys(X86_32_PTABLE_SIZE * INIT_PDIR_SIZE
* sizeof(union x86_32_pdir_entry)));
init_ptable = (void *)local_phys_to_mem(
alloc_phys(X86_32_PTABLE_SIZE * INIT_PDIR_SIZE
* INIT_PTABLE_SIZE * sizeof(union x86_32_ptable_entry)));
/* Page table setup */
/* Initialize init page tables */
for(size_t j = 0; j < INIT_PDIR_SIZE; j++) {
paging_x86_32_clear_pdir(&init_pdir[j]);
for(size_t k = 0; k < INIT_PTABLE_SIZE; k++) {
paging_x86_32_clear_ptable(&init_ptable[j * X86_32_PTABLE_SIZE + k]);
}
}
/* Map pagetables into pageCN */
int pagecn_pagemap = 0;
#ifdef CONFIG_PAE
// Map PDPTE into first slot in pagecn
caps_create_new(ObjType_VNode_x86_32_pdpt,
mem_to_local_phys((lvaddr_t)init_pdpte),
BASE_PAGE_BITS, 0, my_core_id,
caps_locate_slot(CNODE(st->pagecn), pagecn_pagemap++));
#endif
// Map PDIR into successive slots in pagecn
for(size_t i = 0; i < INIT_PDIR_SIZE; i++) {
caps_create_new(ObjType_VNode_x86_32_pdir,
mem_to_local_phys((lvaddr_t)init_pdir) + i * BASE_PAGE_SIZE,
BASE_PAGE_BITS, 0, my_core_id,
caps_locate_slot(CNODE(st->pagecn), pagecn_pagemap++));
}
// Map page tables into successive slots in pagecn
for(size_t i = 0; i < INIT_PTABLE_SIZE; i++) {
caps_create_new(ObjType_VNode_x86_32_ptable,
mem_to_local_phys((lvaddr_t)init_ptable) + i * BASE_PAGE_SIZE,
BASE_PAGE_BITS, 0, my_core_id,
caps_locate_slot(CNODE(st->pagecn), pagecn_pagemap++));
}
// Connect all page tables to page directories.
// init's memory manager expects page tables within the pagecn to
// already be connected to the corresponding directories. To avoid
// unneccessary special cases, we connect them here.
for(lvaddr_t vaddr = 0; vaddr < X86_32_INIT_SPACE_LIMIT;
vaddr += BASE_PAGE_SIZE) {
#ifdef CONFIG_PAE
union x86_32_pdpte_entry *pdpte_base =
&init_pdpte[X86_32_PDPTE_BASE(vaddr)];
union x86_32_pdir_entry *pdir_base =
&init_pdir[X86_32_PDPTE_BASE(vaddr) * X86_32_PTABLE_SIZE +
X86_32_PDIR_BASE(vaddr)];
union x86_32_ptable_entry *ptable_base =
&init_ptable[X86_32_PDPTE_BASE(vaddr) * X86_32_PTABLE_SIZE *
X86_32_PTABLE_SIZE + X86_32_PDIR_BASE(vaddr) *
X86_32_PTABLE_SIZE + X86_32_PTABLE_BASE(vaddr)];
paging_x86_32_map_pdpte(pdpte_base, mem_to_local_phys((lvaddr_t)pdir_base));
#else
union x86_32_pdir_entry *pdir_base =
&init_pdir[X86_32_PDIR_BASE(vaddr)];
union x86_32_ptable_entry *ptable_base =
&init_ptable[X86_32_PDIR_BASE(vaddr) * X86_32_PTABLE_SIZE +
X86_32_PTABLE_BASE(vaddr)];
#endif
paging_x86_32_map_table(pdir_base,
mem_to_local_phys((lvaddr_t)ptable_base));
}
/* Switch to init's VSpace */
#ifdef CONFIG_PAE
paging_x86_32_context_switch(mem_to_local_phys((lvaddr_t)init_pdpte));
#else
paging_x86_32_context_switch(mem_to_local_phys((lvaddr_t)init_pdir));
#endif
/***** VSpace available *****/
/* Map cmdline args R/W into VSpace at ARGS_BASE */
#ifdef CONFIG_PAE
paging_x86_32_map_pdpte(&init_pdpte[X86_32_PDPTE_BASE(ARGS_BASE)],
mem_to_local_phys((lvaddr_t)init_pdir));
#endif
paging_x86_32_map_table(&init_pdir[X86_32_PDIR_BASE(ARGS_BASE)],
mem_to_local_phys((lvaddr_t)init_ptable));
for (int i = 0; i < ARGS_SIZE / BASE_PAGE_SIZE; i++) {
paging_x86_32_map(&init_ptable[X86_32_PTABLE_BASE(ARGS_BASE) + i],
st->args_page + i * BASE_PAGE_SIZE,
INIT_PAGE_BITMAP | paging_elf_to_page_flags(PF_R | PF_W));
}
}