[PATCH 6/6] x86: Convert the rest of the code to support p4d_t

From: Kirill A. Shutemov
Date: Fri Mar 17 2017 - 14:56:54 EST

This patch converts x86 to use proper folding of new page table level
with <asm-generic/pgtable-nop4d.h>.

That's a bit of kitchen sink, but I don't see how to split it further
without hurting bisectability.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/paravirt.h | 33 +++++-
arch/x86/include/asm/paravirt_types.h | 12 ++-
arch/x86/include/asm/pgalloc.h | 35 ++++++-
arch/x86/include/asm/pgtable.h | 59 ++++++++++-
arch/x86/include/asm/pgtable_64.h | 12 ++-
arch/x86/include/asm/pgtable_types.h | 10 +-
arch/x86/include/asm/xen/page.h | 8 +-
arch/x86/kernel/paravirt.c | 10 +-
arch/x86/mm/init_64.c | 183 +++++++++++++++++++++++++++-------
arch/x86/xen/mmu.c | 152 ++++++++++++++++------------
include/trace/events/xen.h | 28 +++---
11 files changed, 401 insertions(+), 141 deletions(-)

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 0489884fdc44..158d877ce9e9 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -536,7 +536,7 @@ static inline void set_pud(pud_t *pudp, pud_t pud)
PVOP_VCALL2(pv_mmu_ops.set_pud, pudp,
val);
}
-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
static inline pud_t __pud(pudval_t val)
{
pudval_t ret;
@@ -565,6 +565,32 @@ static inline pudval_t pud_val(pud_t pud)
return ret;
}

+static inline void pud_clear(pud_t *pudp)
+{
+ set_pud(pudp, __pud(0));
+}
+
+static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
+{
+ p4dval_t val = native_p4d_val(p4d);
+
+ if (sizeof(p4dval_t) > sizeof(long))
+ PVOP_VCALL3(pv_mmu_ops.set_p4d, p4dp,
+ val, (u64)val >> 32);
+ else
+ PVOP_VCALL2(pv_mmu_ops.set_p4d, p4dp,
+ val);
+}
+
+static inline void p4d_clear(p4d_t *p4dp)
+{
+ set_p4d(p4dp, __p4d(0));
+}
+
+#if CONFIG_PGTABLE_LEVELS >= 5
+
+#error FIXME
+
static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
{
pgdval_t val = native_pgd_val(pgd);
@@ -582,10 +608,7 @@ static inline void pgd_clear(pgd_t *pgdp)
set_pgd(pgdp, __pgd(0));
}

-static inline void pud_clear(pud_t *pudp)
-{
- set_pud(pudp, __pud(0));
-}
+#endif /* CONFIG_PGTABLE_LEVELS == 5 */

#endif /* CONFIG_PGTABLE_LEVELS == 4 */

diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index b060f962d581..93c49cf09b63 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -279,12 +279,18 @@ struct pv_mmu_ops {
struct paravirt_callee_save pmd_val;
struct paravirt_callee_save make_pmd;

-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
struct paravirt_callee_save pud_val;
struct paravirt_callee_save make_pud;

- void (*set_pgd)(pgd_t *pudp, pgd_t pgdval);
-#endif /* CONFIG_PGTABLE_LEVELS == 4 */
+ void (*set_p4d)(p4d_t *p4dp, p4d_t p4dval);
+
+#if CONFIG_PGTABLE_LEVELS >= 5
+#error FIXME
+#endif /* CONFIG_PGTABLE_LEVELS >= 5 */
+
+#endif /* CONFIG_PGTABLE_LEVELS >= 4 */
+
#endif /* CONFIG_PGTABLE_LEVELS >= 3 */

struct pv_lazy_ops lazy_mode;
diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h
index b6d425999f99..2f585054c63c 100644
--- a/arch/x86/include/asm/pgalloc.h
+++ b/arch/x86/include/asm/pgalloc.h
@@ -121,10 +121,10 @@ static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
#endif /* CONFIG_X86_PAE */

#if CONFIG_PGTABLE_LEVELS > 3
-static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
+static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
{
paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
- set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(pud)));
+ set_p4d(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
}

static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
@@ -150,6 +150,37 @@ static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
___pud_free_tlb(tlb, pud);
}

+#if CONFIG_PGTABLE_LEVELS > 4
+static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
+{
+ paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
+ set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
+}
+
+static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr)
+{
+ gfp_t gfp = GFP_KERNEL_ACCOUNT;
+
+ if (mm == &init_mm)
+ gfp &= ~__GFP_ACCOUNT;
+ return (p4d_t *)get_zeroed_page(gfp);
+}
+
+static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
+{
+ BUG_ON((unsigned long)p4d & (PAGE_SIZE-1));
+ free_page((unsigned long)p4d);
+}
+
+extern void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d);
+
+static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
+ unsigned long address)
+{
+ ___p4d_free_tlb(tlb, p4d);
+}
+
+#endif /* CONFIG_PGTABLE_LEVELS > 4 */
#endif /* CONFIG_PGTABLE_LEVELS > 3 */
#endif /* CONFIG_PGTABLE_LEVELS > 2 */

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index d5854bd86f0a..adcebc271764 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -51,11 +51,19 @@ extern struct mm_struct *pgd_page_get_mm(struct page *page);

#define set_pmd(pmdp, pmd) native_set_pmd(pmdp, pmd)

-#ifndef __PAGETABLE_PUD_FOLDED
+#ifndef __PAGETABLE_P4D_FOLDED
#define set_pgd(pgdp, pgd) native_set_pgd(pgdp, pgd)
#define pgd_clear(pgd) native_pgd_clear(pgd)
#endif

+#ifndef set_p4d
+# define set_p4d(p4dp, p4d) native_set_p4d(p4dp, p4d)
+#endif
+
+#ifndef __PAGETABLE_PUD_FOLDED
+#define p4d_clear(p4d) native_p4d_clear(p4d)
+#endif
+
#ifndef set_pud
# define set_pud(pudp, pud) native_set_pud(pudp, pud)
#endif
@@ -72,6 +80,11 @@ extern struct mm_struct *pgd_page_get_mm(struct page *page);
#define pgd_val(x) native_pgd_val(x)
#define __pgd(x) native_make_pgd(x)

+#ifndef __PAGETABLE_P4D_FOLDED
+#define p4d_val(x) native_p4d_val(x)
+#define __p4d(x) native_make_p4d(x)
+#endif
+
#ifndef __PAGETABLE_PUD_FOLDED
#define pud_val(x) native_pud_val(x)
#define __pud(x) native_make_pud(x)
@@ -547,6 +560,7 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
#define pte_pgprot(x) __pgprot(pte_flags(x))
#define pmd_pgprot(x) __pgprot(pmd_flags(x))
#define pud_pgprot(x) __pgprot(pud_flags(x))
+#define p4d_pgprot(x) __pgprot(p4d_flags(x))

#define canon_pgprot(p) __pgprot(massage_pgprot(p))

@@ -784,12 +798,47 @@ static inline unsigned long pud_index(unsigned long address)
return (address >> PUD_SHIFT) & (PTRS_PER_PUD - 1);
}

+#if CONFIG_PGTABLE_LEVELS > 3
+static inline int p4d_none(p4d_t p4d)
+{
+ return (native_p4d_val(p4d) & ~(_PAGE_KNL_ERRATUM_MASK)) == 0;
+}
+
+static inline int p4d_present(p4d_t p4d)
+{
+ return p4d_flags(p4d) & _PAGE_PRESENT;
+}
+
+static inline unsigned long p4d_page_vaddr(p4d_t p4d)
+{
+ return (unsigned long)__va(p4d_val(p4d) & p4d_pfn_mask(p4d));
+}
+
+/*
+ * Currently stuck as a macro due to indirect forward reference to
+ * linux/mmzone.h's __section_mem_map_addr() definition:
+ */
+#define p4d_page(p4d) \
+ pfn_to_page((p4d_val(p4d) & p4d_pfn_mask(p4d)) >> PAGE_SHIFT)
+
+/* Find an entry in the third-level page table.. */
+static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
+{
+ return (pud_t *)p4d_page_vaddr(*p4d) + pud_index(address);
+}
+
+static inline int p4d_bad(p4d_t p4d)
+{
+ return (p4d_flags(p4d) & ~(_KERNPG_TABLE | _PAGE_USER)) != 0;
+}
+#endif /* CONFIG_PGTABLE_LEVELS > 3 */
+
static inline unsigned long p4d_index(unsigned long address)
{
return (address >> P4D_SHIFT) & (PTRS_PER_P4D - 1);
}

-#if CONFIG_PGTABLE_LEVELS > 3
+#if CONFIG_PGTABLE_LEVELS > 4
static inline int pgd_present(pgd_t pgd)
{
return pgd_flags(pgd) & _PAGE_PRESENT;
@@ -807,9 +856,9 @@ static inline unsigned long pgd_page_vaddr(pgd_t pgd)
#define pgd_page(pgd) pfn_to_page(pgd_val(pgd) >> PAGE_SHIFT)

/* to find an entry in a page-table-directory. */
-static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
+static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
{
- return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(address);
+ return (p4d_t *)pgd_page_vaddr(*pgd) + p4d_index(address);
}

static inline int pgd_bad(pgd_t pgd)
@@ -827,7 +876,7 @@ static inline int pgd_none(pgd_t pgd)
*/
return !native_pgd_val(pgd);
}
-#endif /* CONFIG_PGTABLE_LEVELS > 3 */
+#endif /* CONFIG_PGTABLE_LEVELS > 4 */

#endif /* __ASSEMBLY__ */

diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index 73c7ccc38912..79396bfdc791 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -41,9 +41,9 @@ extern void paging_init(void);

struct mm_struct;

+void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte);
void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte);

-
static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
@@ -121,6 +121,16 @@ static inline pud_t native_pudp_get_and_clear(pud_t *xp)
#endif
}

+static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
+{
+ *p4dp = p4d;
+}
+
+static inline void native_p4d_clear(p4d_t *p4d)
+{
+ native_set_p4d(p4d, (p4d_t) { .pgd = native_make_pgd(0)});
+}
+
static inline void native_set_pgd(pgd_t *pgdp, pgd_t pgd)
{
*pgdp = pgd;
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index df08535f774a..4930afe9df0a 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -277,11 +277,11 @@ static inline pgdval_t pgd_flags(pgd_t pgd)
#error FIXME

#else
-#include <asm-generic/5level-fixup.h>
+#include <asm-generic/pgtable-nop4d.h>

static inline p4dval_t native_p4d_val(p4d_t p4d)
{
- return native_pgd_val(p4d);
+ return native_pgd_val(p4d.pgd);
}
#endif

@@ -298,12 +298,11 @@ static inline pudval_t native_pud_val(pud_t pud)
return pud.pud;
}
#else
-#define __ARCH_USE_5LEVEL_HACK
#include <asm-generic/pgtable-nopud.h>

static inline pudval_t native_pud_val(pud_t pud)
{
- return native_pgd_val(pud.pgd);
+ return native_pgd_val(pud.p4d.pgd);
}
#endif

@@ -320,12 +319,11 @@ static inline pmdval_t native_pmd_val(pmd_t pmd)
return pmd.pmd;
}
#else
-#define __ARCH_USE_5LEVEL_HACK
#include <asm-generic/pgtable-nopmd.h>

static inline pmdval_t native_pmd_val(pmd_t pmd)
{
- return native_pgd_val(pmd.pud.pgd);
+ return native_pgd_val(pmd.pud.p4d.pgd);
}
#endif

diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h
index 64c5e745ebad..8a5a02b1dfba 100644
--- a/arch/x86/include/asm/xen/page.h
+++ b/arch/x86/include/asm/xen/page.h
@@ -280,13 +280,17 @@ static inline pte_t __pte_ma(pteval_t x)

#define pmd_val_ma(v) ((v).pmd)
#ifdef __PAGETABLE_PUD_FOLDED
-#define pud_val_ma(v) ((v).pgd.pgd)
+#define pud_val_ma(v) ((v).p4d.pgd.pgd)
#else
#define pud_val_ma(v) ((v).pud)
#endif
#define __pmd_ma(x) ((pmd_t) { (x) } )

-#define pgd_val_ma(x) ((x).pgd)
+#ifdef __PAGETABLE_P4D_FOLDED
+#define p4d_val_ma(x) ((x).pgd.pgd)
+#else
+#define p4d_val_ma(x) ((x).p4d)
+#endif

void xen_set_domain_pte(pte_t *ptep, pte_t pteval, unsigned domid);

diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 4797e87b0fb6..110daf22f5c7 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -430,12 +430,16 @@ struct pv_mmu_ops pv_mmu_ops __ro_after_init = {
.pmd_val = PTE_IDENT,
.make_pmd = PTE_IDENT,

-#if CONFIG_PGTABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS >= 4
.pud_val = PTE_IDENT,
.make_pud = PTE_IDENT,

- .set_pgd = native_set_pgd,
-#endif
+ .set_p4d = native_set_p4d,
+
+#if CONFIG_PGTABLE_LEVELS >= 5
+#error FIXME
+#endif /* CONFIG_PGTABLE_LEVELS >= 4 */
+#endif /* CONFIG_PGTABLE_LEVELS >= 4 */
#endif /* CONFIG_PGTABLE_LEVELS >= 3 */

.pte_val = PTE_IDENT,
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index f6da869810a8..a242139df8fe 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -97,28 +97,38 @@ void sync_global_pgds(unsigned long start, unsigned long end)
unsigned long address;

for (address = start; address <= end; address += PGDIR_SIZE) {
- const pgd_t *pgd_ref = pgd_offset_k(address);
+ pgd_t *pgd_ref = pgd_offset_k(address);
+ const p4d_t *p4d_ref;
struct page *page;

- if (pgd_none(*pgd_ref))
+ /*
+ * With folded p4d, pgd_none() is always false, we need to
+ * handle synchonization on p4d level.
+ */
+ BUILD_BUG_ON(pgd_none(*pgd_ref));
+ p4d_ref = p4d_offset(pgd_ref, address);
+
+ if (p4d_none(*p4d_ref))
continue;

spin_lock(&pgd_lock);
list_for_each_entry(page, &pgd_list, lru) {
pgd_t *pgd;
+ p4d_t *p4d;
spinlock_t *pgt_lock;

pgd = (pgd_t *)page_address(page) + pgd_index(address);
+ p4d = p4d_offset(pgd, address);
/* the pgt_lock only for Xen */
pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
spin_lock(pgt_lock);

- if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
- BUG_ON(pgd_page_vaddr(*pgd)
- != pgd_page_vaddr(*pgd_ref));
+ if (!p4d_none(*p4d_ref) && !p4d_none(*p4d))
+ BUG_ON(p4d_page_vaddr(*p4d)
+ != p4d_page_vaddr(*p4d_ref));

- if (pgd_none(*pgd))
- set_pgd(pgd, *pgd_ref);
+ if (p4d_none(*p4d))
+ set_p4d(p4d, *p4d_ref);

spin_unlock(pgt_lock);
}
@@ -149,16 +159,28 @@ static __ref void *spp_getpage(void)
return ptr;
}

-static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
+static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr)
{
if (pgd_none(*pgd)) {
- pud_t *pud = (pud_t *)spp_getpage();
- pgd_populate(&init_mm, pgd, pud);
- if (pud != pud_offset(pgd, 0))
+ p4d_t *p4d = (p4d_t *)spp_getpage();
+ pgd_populate(&init_mm, pgd, p4d);
+ if (p4d != p4d_offset(pgd, 0))
printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
- pud, pud_offset(pgd, 0));
+ p4d, p4d_offset(pgd, 0));
+ }
+ return p4d_offset(pgd, vaddr);
+}
+
+static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr)
+{
+ if (p4d_none(*p4d)) {
+ pud_t *pud = (pud_t *)spp_getpage();
+ p4d_populate(&init_mm, p4d, pud);
+ if (pud != pud_offset(p4d, 0))
+ printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
+ pud, pud_offset(p4d, 0));
}
- return pud_offset(pgd, vaddr);
+ return pud_offset(p4d, vaddr);
}

static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
@@ -167,7 +189,7 @@ static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
pmd_t *pmd = (pmd_t *) spp_getpage();
pud_populate(&init_mm, pud, pmd);
if (pmd != pmd_offset(pud, 0))
- printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
+ printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n",
pmd, pmd_offset(pud, 0));
}
return pmd_offset(pud, vaddr);
@@ -179,20 +201,15 @@ static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
pte_t *pte = (pte_t *) spp_getpage();
pmd_populate_kernel(&init_mm, pmd, pte);
if (pte != pte_offset_kernel(pmd, 0))
- printk(KERN_ERR "PAGETABLE BUG #02!\n");
+ printk(KERN_ERR "PAGETABLE BUG #03!\n");
}
return pte_offset_kernel(pmd, vaddr);
}

-void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
+static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte)
{
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
-
- pud = pud_page + pud_index(vaddr);
- pmd = fill_pmd(pud, vaddr);
- pte = fill_pte(pmd, vaddr);
+ pmd_t *pmd = fill_pmd(pud, vaddr);
+ pte_t *pte = fill_pte(pmd, vaddr);

set_pte(pte, new_pte);

@@ -203,10 +220,25 @@ void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
__flush_tlb_one(vaddr);
}

+void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte)
+{
+ p4d_t *p4d = p4d_page + p4d_index(vaddr);
+ pud_t *pud = fill_pud(p4d, vaddr);
+
+ __set_pte_vaddr(pud, vaddr, new_pte);
+}
+
+void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
+{
+ pud_t *pud = pud_page + pud_index(vaddr);
+
+ __set_pte_vaddr(pud, vaddr, new_pte);
+}
+
void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
{
pgd_t *pgd;
- pud_t *pud_page;
+ p4d_t *p4d_page;

pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));

@@ -216,17 +248,20 @@ void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
"PGD FIXMAP MISSING, it should be setup in head.S!\n");
return;
}
- pud_page = (pud_t*)pgd_page_vaddr(*pgd);
- set_pte_vaddr_pud(pud_page, vaddr, pteval);
+
+ p4d_page = p4d_offset(pgd, 0);
+ set_pte_vaddr_p4d(p4d_page, vaddr, pteval);
}

pmd_t * __init populate_extra_pmd(unsigned long vaddr)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;

pgd = pgd_offset_k(vaddr);
- pud = fill_pud(pgd, vaddr);
+ p4d = fill_p4d(pgd, vaddr);
+ pud = fill_pud(p4d, vaddr);
return fill_pmd(pud, vaddr);
}

@@ -245,6 +280,7 @@ static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
enum page_cache_mode cache)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pgprot_t prot;
@@ -255,11 +291,17 @@ static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
pgd = pgd_offset_k((unsigned long)__va(phys));
if (pgd_none(*pgd)) {
+ p4d = (p4d_t *) spp_getpage();
+ set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE |
+ _PAGE_USER));
+ }
+ p4d = p4d_offset(pgd, (unsigned long)__va(phys));
+ if (p4d_none(*p4d)) {
pud = (pud_t *) spp_getpage();
- set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
+ set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE |
_PAGE_USER));
}
- pud = pud_offset(pgd, (unsigned long)__va(phys));
+ pud = pud_offset(p4d, (unsigned long)__va(phys));
if (pud_none(*pud)) {
pmd = (pmd_t *) spp_getpage();
set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
@@ -563,12 +605,15 @@ kernel_physical_mapping_init(unsigned long paddr_start,

for (; vaddr < vaddr_end; vaddr = vaddr_next) {
pgd_t *pgd = pgd_offset_k(vaddr);
+ p4d_t *p4d;
pud_t *pud;

vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;

- if (pgd_val(*pgd)) {
- pud = (pud_t *)pgd_page_vaddr(*pgd);
+ BUILD_BUG_ON(pgd_none(*pgd));
+ p4d = p4d_offset(pgd, vaddr);
+ if (p4d_val(*p4d)) {
+ pud = (pud_t *)p4d_page_vaddr(*p4d);
paddr_last = phys_pud_init(pud, __pa(vaddr),
__pa(vaddr_end),
page_size_mask);
@@ -580,7 +625,7 @@ kernel_physical_mapping_init(unsigned long paddr_start,
page_size_mask);

spin_lock(&init_mm.page_table_lock);
- pgd_populate(&init_mm, pgd, pud);
+ p4d_populate(&init_mm, p4d, pud);
spin_unlock(&init_mm.page_table_lock);
pgd_changed = true;
}
@@ -726,6 +771,24 @@ static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
spin_unlock(&init_mm.page_table_lock);
}

+static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
+{
+ pud_t *pud;
+ int i;
+
+ for (i = 0; i < PTRS_PER_PUD; i++) {
+ pud = pud_start + i;
+ if (!pud_none(*pud))
+ return;
+ }
+
+ /* free a pud talbe */
+ free_pagetable(p4d_page(*p4d), 0);
+ spin_lock(&init_mm.page_table_lock);
+ p4d_clear(p4d);
+ spin_unlock(&init_mm.page_table_lock);
+}
+
static void __meminit
remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
bool direct)
@@ -908,6 +971,32 @@ remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
update_page_count(PG_LEVEL_1G, -pages);
}

+static void __meminit
+remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
+ bool direct)
+{
+ unsigned long next, pages = 0;
+ pud_t *pud_base;
+ p4d_t *p4d;
+
+ p4d = p4d_start + p4d_index(addr);
+ for (; addr < end; addr = next, p4d++) {
+ next = p4d_addr_end(addr, end);
+
+ if (!p4d_present(*p4d))
+ continue;
+
+ BUILD_BUG_ON(p4d_large(*p4d));
+
+ pud_base = (pud_t *)p4d_page_vaddr(*p4d);
+ remove_pud_table(pud_base, addr, next, direct);
+ free_pud_table(pud_base, p4d);
+ }
+
+ if (direct)
+ update_page_count(PG_LEVEL_512G, -pages);
+}
+
/* start and end are both virtual address. */
static void __meminit
remove_pagetable(unsigned long start, unsigned long end, bool direct)
@@ -915,7 +1004,7 @@ remove_pagetable(unsigned long start, unsigned long end, bool direct)
unsigned long next;
unsigned long addr;
pgd_t *pgd;
- pud_t *pud;
+ p4d_t *p4d;

for (addr = start; addr < end; addr = next) {
next = pgd_addr_end(addr, end);
@@ -924,8 +1013,8 @@ remove_pagetable(unsigned long start, unsigned long end, bool direct)
if (!pgd_present(*pgd))
continue;

- pud = (pud_t *)pgd_page_vaddr(*pgd);
- remove_pud_table(pud, addr, next, direct);
+ p4d = (p4d_t *)pgd_page_vaddr(*pgd);
+ remove_p4d_table(p4d, addr, next, direct);
}

flush_tlb_all();
@@ -1090,6 +1179,7 @@ int kern_addr_valid(unsigned long addr)
{
unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
@@ -1101,7 +1191,11 @@ int kern_addr_valid(unsigned long addr)
if (pgd_none(*pgd))
return 0;

- pud = pud_offset(pgd, addr);
+ p4d = p4d_offset(pgd, addr);
+ if (p4d_none(*p4d))
+ return 0;
+
+ pud = pud_offset(p4d, addr);
if (pud_none(*pud))
return 0;

@@ -1158,6 +1252,7 @@ static int __meminit vmemmap_populate_hugepages(unsigned long start,
unsigned long addr;
unsigned long next;
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;

@@ -1168,7 +1263,11 @@ static int __meminit vmemmap_populate_hugepages(unsigned long start,
if (!pgd)
return -ENOMEM;

- pud = vmemmap_pud_populate(pgd, addr, node);
+ p4d = vmemmap_p4d_populate(pgd, addr, node);
+ if (!p4d)
+ return -ENOMEM;
+
+ pud = vmemmap_pud_populate(p4d, addr, node);
if (!pud)
return -ENOMEM;

@@ -1236,6 +1335,7 @@ void register_page_bootmem_memmap(unsigned long section_nr,
unsigned long end = (unsigned long)(start_page + size);
unsigned long next;
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
unsigned int nr_pages;
@@ -1251,7 +1351,14 @@ void register_page_bootmem_memmap(unsigned long section_nr,
}
get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);

- pud = pud_offset(pgd, addr);
+ p4d = p4d_offset(pgd, addr);
+ if (p4d_none(*p4d)) {
+ next = (addr + PAGE_SIZE) & PAGE_MASK;
+ continue;
+ }
+ get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
+
+ pud = pud_offset(p4d, addr);
if (pud_none(*pud)) {
next = (addr + PAGE_SIZE) & PAGE_MASK;
continue;
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index b3c4f13e48a4..f226038a39ca 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++;
+ 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);
+ }
+ 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_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_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;
}
- 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;
- }
+ 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,
diff --git a/include/trace/events/xen.h b/include/trace/events/xen.h
index bce990f5a35d..31acce9019a6 100644
--- a/include/trace/events/xen.h
+++ b/include/trace/events/xen.h
@@ -241,21 +241,21 @@ TRACE_EVENT(xen_mmu_set_pud,
(int)sizeof(pudval_t) * 2, (unsigned long long)__entry->pudval)
);

-TRACE_EVENT(xen_mmu_set_pgd,
- TP_PROTO(pgd_t *pgdp, pgd_t *user_pgdp, pgd_t pgdval),
- TP_ARGS(pgdp, user_pgdp, pgdval),
+TRACE_EVENT(xen_mmu_set_p4d,
+ TP_PROTO(p4d_t *p4dp, p4d_t *user_p4dp, p4d_t p4dval),
+ TP_ARGS(p4dp, user_p4dp, p4dval),
TP_STRUCT__entry(
- __field(pgd_t *, pgdp)
- __field(pgd_t *, user_pgdp)
- __field(pgdval_t, pgdval)
- ),
- TP_fast_assign(__entry->pgdp = pgdp;
- __entry->user_pgdp = user_pgdp;
- __entry->pgdval = pgdval.pgd),
- TP_printk("pgdp %p user_pgdp %p pgdval %0*llx (raw %0*llx)",
- __entry->pgdp, __entry->user_pgdp,
- (int)sizeof(pgdval_t) * 2, (unsigned long long)pgd_val(native_make_pgd(__entry->pgdval)),
- (int)sizeof(pgdval_t) * 2, (unsigned long long)__entry->pgdval)
+ __field(p4d_t *, p4dp)
+ __field(p4d_t *, user_p4dp)
+ __field(p4dval_t, p4dval)
+ ),
+ TP_fast_assign(__entry->p4dp = p4dp;
+ __entry->user_p4dp = user_p4dp;
+ __entry->p4dval = p4d_val(p4dval)),
+ TP_printk("p4dp %p user_p4dp %p p4dval %0*llx (raw %0*llx)",
+ __entry->p4dp, __entry->user_p4dp,
+ (int)sizeof(p4dval_t) * 2, (unsigned long long)pgd_val(native_make_pgd(__entry->p4dval)),
+ (int)sizeof(p4dval_t) * 2, (unsigned long long)__entry->p4dval)
);

TRACE_EVENT(xen_mmu_pud_clear,
--
2.11.0