x86: Convert the rest of the code to support p4d_t
This patch converts x86 to use proper folding of a new (fifth) page table level
with <asm-generic/pgtable-nop4d.h>.
That's a bit of a kitchen sink patch, but I don't see how to split it further
without hurting bisectability.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170317185515.8636-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index e6adebb..4d4b7bc 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -535,40 +535,41 @@ static pgd_t *xen_get_user_pgd(pgd_t *pgd)
return user_ptr;
}
-static void __xen_set_pgd_hyper(pgd_t *ptr, pgd_t val)
+static void __xen_set_p4d_hyper(p4d_t *ptr, p4d_t val)
{
struct mmu_update u;
u.ptr = virt_to_machine(ptr).maddr;
- u.val = pgd_val_ma(val);
+ u.val = p4d_val_ma(val);
xen_extend_mmu_update(&u);
}
/*
- * Raw hypercall-based set_pgd, intended for in early boot before
+ * Raw hypercall-based set_p4d, intended for in early boot before
* there's a page structure. This implies:
* 1. The only existing pagetable is the kernel's
* 2. It is always pinned
* 3. It has no user pagetable attached to it
*/
-static void __init xen_set_pgd_hyper(pgd_t *ptr, pgd_t val)
+static void __init xen_set_p4d_hyper(p4d_t *ptr, p4d_t val)
{
preempt_disable();
xen_mc_batch();
- __xen_set_pgd_hyper(ptr, val);
+ __xen_set_p4d_hyper(ptr, val);
xen_mc_issue(PARAVIRT_LAZY_MMU);
preempt_enable();
}
-static void xen_set_pgd(pgd_t *ptr, pgd_t val)
+static void xen_set_p4d(p4d_t *ptr, p4d_t val)
{
- pgd_t *user_ptr = xen_get_user_pgd(ptr);
+ pgd_t *user_ptr = xen_get_user_pgd((pgd_t *)ptr);
+ pgd_t pgd_val;
- trace_xen_mmu_set_pgd(ptr, user_ptr, val);
+ trace_xen_mmu_set_p4d(ptr, (p4d_t *)user_ptr, val);
/* If page is not pinned, we can just update the entry
directly */
@@ -576,7 +577,8 @@ static void xen_set_pgd(pgd_t *ptr, pgd_t val)
*ptr = val;
if (user_ptr) {
WARN_ON(xen_page_pinned(user_ptr));
- *user_ptr = val;
+ pgd_val.pgd = p4d_val_ma(val);
+ *user_ptr = pgd_val;
}
return;
}
@@ -585,9 +587,9 @@ static void xen_set_pgd(pgd_t *ptr, pgd_t val)
user updates together. */
xen_mc_batch();
- __xen_set_pgd_hyper(ptr, val);
+ __xen_set_p4d_hyper(ptr, val);
if (user_ptr)
- __xen_set_pgd_hyper(user_ptr, val);
+ __xen_set_p4d_hyper((p4d_t *)user_ptr, val);
xen_mc_issue(PARAVIRT_LAZY_MMU);
}
@@ -1591,7 +1593,6 @@ static int xen_pgd_alloc(struct mm_struct *mm)
BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd))));
}
#endif
-
return ret;
}
@@ -1783,7 +1784,7 @@ static void xen_release_pmd(unsigned long pfn)
xen_release_ptpage(pfn, PT_PMD);
}
-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
static void xen_alloc_pud(struct mm_struct *mm, unsigned long pfn)
{
xen_alloc_ptpage(mm, pfn, PT_PUD);
@@ -2124,21 +2125,27 @@ static phys_addr_t __init xen_early_virt_to_phys(unsigned long vaddr)
*/
void __init xen_relocate_p2m(void)
{
- phys_addr_t size, new_area, pt_phys, pmd_phys, pud_phys;
+ phys_addr_t size, new_area, pt_phys, pmd_phys, pud_phys, p4d_phys;
unsigned long p2m_pfn, p2m_pfn_end, n_frames, pfn, pfn_end;
- int n_pte, n_pt, n_pmd, n_pud, idx_pte, idx_pt, idx_pmd, idx_pud;
+ int n_pte, n_pt, n_pmd, n_pud, n_p4d, idx_pte, idx_pt, idx_pmd, idx_pud, idx_p4d;
pte_t *pt;
pmd_t *pmd;
pud_t *pud;
+ p4d_t *p4d = NULL;
pgd_t *pgd;
unsigned long *new_p2m;
+ int save_pud;
size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long));
n_pte = roundup(size, PAGE_SIZE) >> PAGE_SHIFT;
n_pt = roundup(size, PMD_SIZE) >> PMD_SHIFT;
n_pmd = roundup(size, PUD_SIZE) >> PUD_SHIFT;
- n_pud = roundup(size, PGDIR_SIZE) >> PGDIR_SHIFT;
- n_frames = n_pte + n_pt + n_pmd + n_pud;
+ n_pud = roundup(size, P4D_SIZE) >> P4D_SHIFT;
+ if (PTRS_PER_P4D > 1)
+ n_p4d = roundup(size, PGDIR_SIZE) >> PGDIR_SHIFT;
+ else
+ n_p4d = 0;
+ n_frames = n_pte + n_pt + n_pmd + n_pud + n_p4d;
new_area = xen_find_free_area(PFN_PHYS(n_frames));
if (!new_area) {
@@ -2154,55 +2161,76 @@ void __init xen_relocate_p2m(void)
* To avoid any possible virtual address collision, just use
* 2 * PUD_SIZE for the new area.
*/
- pud_phys = new_area;
+ p4d_phys = new_area;
+ pud_phys = p4d_phys + PFN_PHYS(n_p4d);
pmd_phys = pud_phys + PFN_PHYS(n_pud);
pt_phys = pmd_phys + PFN_PHYS(n_pmd);
p2m_pfn = PFN_DOWN(pt_phys) + n_pt;
pgd = __va(read_cr3());
new_p2m = (unsigned long *)(2 * PGDIR_SIZE);
- for (idx_pud = 0; idx_pud < n_pud; idx_pud++) {
- pud = early_memremap(pud_phys, PAGE_SIZE);
- clear_page(pud);
- for (idx_pmd = 0; idx_pmd < min(n_pmd, PTRS_PER_PUD);
- idx_pmd++) {
- pmd = early_memremap(pmd_phys, PAGE_SIZE);
- clear_page(pmd);
- for (idx_pt = 0; idx_pt < min(n_pt, PTRS_PER_PMD);
- idx_pt++) {
- pt = early_memremap(pt_phys, PAGE_SIZE);
- clear_page(pt);
- for (idx_pte = 0;
- idx_pte < min(n_pte, PTRS_PER_PTE);
- idx_pte++) {
- set_pte(pt + idx_pte,
- pfn_pte(p2m_pfn, PAGE_KERNEL));
- p2m_pfn++;
- }
- n_pte -= PTRS_PER_PTE;
- early_memunmap(pt, PAGE_SIZE);
- make_lowmem_page_readonly(__va(pt_phys));
- pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE,
- PFN_DOWN(pt_phys));
- set_pmd(pmd + idx_pt,
- __pmd(_PAGE_TABLE | pt_phys));
- pt_phys += PAGE_SIZE;
- }
- n_pt -= PTRS_PER_PMD;
- early_memunmap(pmd, PAGE_SIZE);
- make_lowmem_page_readonly(__va(pmd_phys));
- pin_pagetable_pfn(MMUEXT_PIN_L2_TABLE,
- PFN_DOWN(pmd_phys));
- set_pud(pud + idx_pmd, __pud(_PAGE_TABLE | pmd_phys));
- pmd_phys += PAGE_SIZE;
+ idx_p4d = 0;
+ save_pud = n_pud;
+ do {
+ if (n_p4d > 0) {
+ p4d = early_memremap(p4d_phys, PAGE_SIZE);
+ clear_page(p4d);
+ n_pud = min(save_pud, PTRS_PER_P4D);
}
- n_pmd -= PTRS_PER_PUD;
- early_memunmap(pud, PAGE_SIZE);
- make_lowmem_page_readonly(__va(pud_phys));
- pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(pud_phys));
- set_pgd(pgd + 2 + idx_pud, __pgd(_PAGE_TABLE | pud_phys));
- pud_phys += PAGE_SIZE;
- }
+ for (idx_pud = 0; idx_pud < n_pud; idx_pud++) {
+ pud = early_memremap(pud_phys, PAGE_SIZE);
+ clear_page(pud);
+ for (idx_pmd = 0; idx_pmd < min(n_pmd, PTRS_PER_PUD);
+ idx_pmd++) {
+ pmd = early_memremap(pmd_phys, PAGE_SIZE);
+ clear_page(pmd);
+ for (idx_pt = 0; idx_pt < min(n_pt, PTRS_PER_PMD);
+ idx_pt++) {
+ pt = early_memremap(pt_phys, PAGE_SIZE);
+ clear_page(pt);
+ for (idx_pte = 0;
+ idx_pte < min(n_pte, PTRS_PER_PTE);
+ idx_pte++) {
+ set_pte(pt + idx_pte,
+ pfn_pte(p2m_pfn, PAGE_KERNEL));
+ p2m_pfn++;
+ }
+ n_pte -= PTRS_PER_PTE;
+ early_memunmap(pt, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pt_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE,
+ PFN_DOWN(pt_phys));
+ set_pmd(pmd + idx_pt,
+ __pmd(_PAGE_TABLE | pt_phys));
+ pt_phys += PAGE_SIZE;
+ }
+ n_pt -= PTRS_PER_PMD;
+ early_memunmap(pmd, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pmd_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L2_TABLE,
+ PFN_DOWN(pmd_phys));
+ set_pud(pud + idx_pmd, __pud(_PAGE_TABLE | pmd_phys));
+ pmd_phys += PAGE_SIZE;
+ }
+ n_pmd -= PTRS_PER_PUD;
+ early_memunmap(pud, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pud_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(pud_phys));
+ if (n_p4d > 0)
+ set_p4d(p4d + idx_pud, __p4d(_PAGE_TABLE | pud_phys));
+ else
+ set_pgd(pgd + 2 + idx_pud, __pgd(_PAGE_TABLE | pud_phys));
+ pud_phys += PAGE_SIZE;
+ }
+ if (n_p4d > 0) {
+ save_pud -= PTRS_PER_P4D;
+ early_memunmap(p4d, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(p4d_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE, PFN_DOWN(p4d_phys));
+ set_pgd(pgd + 2 + idx_p4d, __pgd(_PAGE_TABLE | p4d_phys));
+ p4d_phys += PAGE_SIZE;
+ }
+ } while (++idx_p4d < n_p4d);
/* Now copy the old p2m info to the new area. */
memcpy(new_p2m, xen_p2m_addr, size);
@@ -2432,8 +2460,8 @@ static void __init xen_post_allocator_init(void)
pv_mmu_ops.set_pte = xen_set_pte;
pv_mmu_ops.set_pmd = xen_set_pmd;
pv_mmu_ops.set_pud = xen_set_pud;
-#if CONFIG_PGTABLE_LEVELS == 4
- pv_mmu_ops.set_pgd = xen_set_pgd;
+#if CONFIG_PGTABLE_LEVELS >= 4
+ pv_mmu_ops.set_p4d = xen_set_p4d;
#endif
/* This will work as long as patching hasn't happened yet
@@ -2442,7 +2470,7 @@ static void __init xen_post_allocator_init(void)
pv_mmu_ops.alloc_pmd = xen_alloc_pmd;
pv_mmu_ops.release_pte = xen_release_pte;
pv_mmu_ops.release_pmd = xen_release_pmd;
-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
pv_mmu_ops.alloc_pud = xen_alloc_pud;
pv_mmu_ops.release_pud = xen_release_pud;
#endif
@@ -2508,10 +2536,10 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
.make_pmd = PV_CALLEE_SAVE(xen_make_pmd),
.pmd_val = PV_CALLEE_SAVE(xen_pmd_val),
-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
.pud_val = PV_CALLEE_SAVE(xen_pud_val),
.make_pud = PV_CALLEE_SAVE(xen_make_pud),
- .set_pgd = xen_set_pgd_hyper,
+ .set_p4d = xen_set_p4d_hyper,
.alloc_pud = xen_alloc_pmd_init,
.release_pud = xen_release_pmd_init,