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x86: add support for 64-bit thread ptables

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Slightly different layout since the top-lebel PML4
is page-sized and must be page-aligned.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
This commit is contained in:
Andrew Boie 2019-11-19 12:31:25 -08:00 • committed by Anas Nashif
commit 7c293831c6
1 changed files with 95 additions and 29 deletions
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124
arch/x86/core/x86_mmu.c
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@ -783,6 +783,35 @@ int arch_buffer_validate(void *addr, size_t size, int write)
size, write != 0);
}
#ifdef CONFIG_X86_64
static uintptr_t thread_pdpt_create(uintptr_t pages,
struct x86_page_tables *thread_ptables,
struct x86_page_tables *master_ptables)
{
uintptr_t pos = pages, phys_addr = Z_X86_PDPT_START;
for (int i = 0; i < Z_X86_NUM_PDPT; i++, phys_addr += Z_X86_PDPT_AREA) {
u64_t *pml4e;
struct x86_mmu_pdpt *master_pdpt, *dest_pdpt;
/* obtain master PDPT tables for the address range and copy
* into per-thread PDPT for this range
*/
master_pdpt = z_x86_get_pdpt(master_ptables, phys_addr);
dest_pdpt = (struct x86_mmu_pdpt *)pos;
(void)memcpy(dest_pdpt, master_pdpt,
sizeof(struct x86_mmu_pdpt));
/* And then wire this up to the relevant per-thread PML4E */
pml4e = z_x86_get_pml4e(thread_ptables, phys_addr);
pml4e_update_pdpt(pml4e, dest_pdpt);
pos += MMU_PAGE_SIZE;
}
return pos;
}
#endif /* CONFIG_X86_64 */
static uintptr_t thread_pd_create(uintptr_t pages,
struct x86_page_tables *thread_ptables,
struct x86_page_tables *master_ptables)
@ -845,6 +874,65 @@ static uintptr_t thread_pt_create(uintptr_t pages,
/* Initialize the page tables for a thread. This will contain, once done,
* the boot-time configuration for a user thread page tables. There are
* no pre-conditions on the existing state of the per-thread tables.
*
* pos represents the page we are working with in the reserved area
* in the stack buffer for per-thread tables. As we create tables in
* this area, pos is incremented to the next free page.
*
* The layout of the stack object, when this is done:
*
* For 32-bit:
*
* +---------------------------+ <- thread->stack_obj
* | PDE(0) |
* +---------------------------+
* | ... |
* +---------------------------+
* | PDE(Z_X86_NUM_PD - 1) |
* +---------------------------+
* | PTE(0) |
* +---------------------------+
* | ... |
* +---------------------------+
* | PTE(Z_X86_NUM_PT - 1) |
* +---------------------------+ <- pos once this logic completes
* | Stack guard |
* +---------------------------+
* | Privilege elevation stack |
* | PDPT |
* +---------------------------+ <- thread->stack_info.start
* | Thread stack |
* | ... |
*
* For 64-bit:
*
* +---------------------------+ <- thread->stack_obj
* | PML4 |
* +---------------------------|
* | PDPT(0) |
* +---------------------------|
* | ... |
* +---------------------------|
* | PDPT(Z_X86_NUM_PDPT - 1) |
* +---------------------------+
* | PDE(0) |
* +---------------------------+
* | ... |
* +---------------------------+
* | PDE(Z_X86_NUM_PD - 1) |
* +---------------------------+
* | PTE(0) |
* +---------------------------+
* | ... |
* +---------------------------+
* | PTE(Z_X86_NUM_PT - 1) |
* +---------------------------+ <- pos once this logic completes
* | Stack guard |
* +---------------------------+
* | Privilege elevation stack |
* +---------------------------+ <- thread->stack_info.start
* | Thread stack |
* | ... |
*/
static void copy_page_tables(struct k_thread *thread,
struct x86_page_tables *master_ptables)
@ -864,36 +952,14 @@ static void copy_page_tables(struct k_thread *thread,
(void)memcpy(thread_ptables, master_ptables,
sizeof(struct x86_page_tables));
/* pos represents the page we are working with in the reserved area
* in the stack buffer for per-thread tables. As we create tables in
* this area, pos is incremented to the next free page.
*
* The layout of the stack object, when this is done:
*
* +---------------------------+ <- thread->stack_obj
* | PDE(0) |
* +---------------------------+
* | ... |
* +---------------------------+
* | PDE(Z_X86_NUM_PD - 1) |
* +---------------------------+
* | PTE(0) |
* +---------------------------+
* | ... |
* +---------------------------+
* | PTE(Z_X86_NUM_PT - 1) |
* +---------------------------+ <- pos once this logic completes
* | Stack guard |
* +---------------------------+
* | Privilege elevation stack |
* | PDPT |
* +---------------------------+ <- thread->stack_info.start
* | Thread stack |
* | ... |
*
*/
start = (uintptr_t)(&header->page_tables);
pos = thread_pd_create(start, thread_ptables, master_ptables);
#ifdef CONFIG_X86_64
pos = start + sizeof(struct x86_mmu_pml4);
pos = thread_pdpt_create(pos, thread_ptables, master_ptables);
#else
pos = start;
#endif
pos = thread_pd_create(pos, thread_ptables, master_ptables);
pos = thread_pt_create(pos, thread_ptables, master_ptables);
__ASSERT(pos == (start + Z_X86_THREAD_PT_AREA),