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linux-stable/arch/sparc/include/asm/pgtable_64.h
David Hildenbrand fa2e71a6fc sparc/mm: don't unconditionally set HW writable bit when setting PTE dirty on 64bit 
On sparc64, there is no HW modified bit, therefore, SW tracks via a SW bit
if the PTE is dirty via pte_mkdirty().  However, pte_mkdirty() currently
also unconditionally sets the HW writable bit, which is wrong.

pte_mkdirty() is not supposed to make a PTE actually writable, unless the
SW writable bit -- pte_write() -- indicates that the PTE is not
write-protected.  Fortunately, sparc64 also defines a SW writable bit.

For example, this already turned into a problem in the context of THP
splitting as documented in commit 624a2c94f5 ("Partly revert "mm/thp:
carry over dirty bit when thp splits on pmd""), and for page migration, as
documented in commit 96a9c287e2 ("mm/migrate: fix wrongly apply write
bit after mkdirty on sparc64").

Also, we might want to use the dirty PTE bit in the context of KSM with
shared zeropage [1], whereby setting the page writable would be
problematic.

But more general, any code that might end up setting a PTE/PMD dirty
inside a VM without write permissions is possibly broken,

Before this commit (sun4u in QEMU):
	root@debian:~/linux/tools/testing/selftests/mm# ./mkdirty
	# [INFO] detected THP size: 8192 KiB
	TAP version 13
	1..6
	# [INFO] PTRACE write access
	not ok 1 SIGSEGV generated, page not modified
	# [INFO] PTRACE write access to THP
	not ok 2 SIGSEGV generated, page not modified
	# [INFO] Page migration
	ok 3 SIGSEGV generated, page not modified
	# [INFO] Page migration of THP
	ok 4 SIGSEGV generated, page not modified
	# [INFO] PTE-mapping a THP
	ok 5 SIGSEGV generated, page not modified
	# [INFO] UFFDIO_COPY
	not ok 6 SIGSEGV generated, page not modified
	Bail out! 3 out of 6 tests failed
	# Totals: pass:3 fail:3 xfail:0 xpass:0 skip:0 error:0

Test #3,#4,#5 pass ever since we added some MM workarounds, the
underlying issue remains.

Let's fix the remaining issues and prepare for reverting the workarounds
by setting the HW writable bit only if both, the SW dirty bit and the SW
writable bit are set.

We have to move pte_dirty() and pte_write() up. The code patching
mechanism and handling constants > 22bit is a bit special on sparc64.

The ASM logic in pte_mkdirty() and pte_mkwrite() match the logic in
pte_mkold() to create the mask depending on the machine type. The ASM
logic in __pte_mkhwwrite() matches the logic in pte_present(), just
using an "or" instead of an "and" instruction.

With this commit (sun4u in QEMU):
	root@debian:~/linux/tools/testing/selftests/mm# ./mkdirty
	# [INFO] detected THP size: 8192 KiB
	TAP version 13
	1..6
	# [INFO] PTRACE write access
	ok 1 SIGSEGV generated, page not modified
	# [INFO] PTRACE write access to THP
	ok 2 SIGSEGV generated, page not modified
	# [INFO] Page migration
	ok 3 SIGSEGV generated, page not modified
	# [INFO] Page migration of THP
	ok 4 SIGSEGV generated, page not modified
	# [INFO] PTE-mapping a THP
	ok 5 SIGSEGV generated, page not modified
	# [INFO] UFFDIO_COPY
	ok 6 SIGSEGV generated, page not modified
	# Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0

This handling seems to have been in place forever.

[1] https://lkml.kernel.org/r/533a7c3d-3a48-b16b-b421-6e8386e0b142@redhat.com

Link: https://lkml.kernel.org/r/20230411142512.438404-4-david@redhat.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18 16:30:00 -07:00

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/* SPDX-License-Identifier: GPL-2.0 */
/*
* pgtable.h: SpitFire page table operations.
*
* Copyright 1996,1997 David S. Miller (davem@caip.rutgers.edu)
* Copyright 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#ifndef _SPARC64_PGTABLE_H
#define _SPARC64_PGTABLE_H
/* This file contains the functions and defines necessary to modify and use
* the SpitFire page tables.
*/
#include <asm-generic/pgtable-nop4d.h>
#include <linux/compiler.h>
#include <linux/const.h>
#include <asm/types.h>
#include <asm/spitfire.h>
#include <asm/asi.h>
#include <asm/adi.h>
#include <asm/page.h>
#include <asm/processor.h>
/* The kernel image occupies 0x4000000 to 0x6000000 (4MB --> 96MB).
* The page copy blockops can use 0x6000000 to 0x8000000.
* The 8K TSB is mapped in the 0x8000000 to 0x8400000 range.
* The 4M TSB is mapped in the 0x8400000 to 0x8800000 range.
* The PROM resides in an area spanning 0xf0000000 to 0x100000000.
* The vmalloc area spans 0x100000000 to 0x200000000.
* Since modules need to be in the lowest 32-bits of the address space,
* we place them right before the OBP area from 0x10000000 to 0xf0000000.
* There is a single static kernel PMD which maps from 0x0 to address
* 0x400000000.
*/
#define TLBTEMP_BASE _AC(0x0000000006000000,UL)
#define TSBMAP_8K_BASE _AC(0x0000000008000000,UL)
#define TSBMAP_4M_BASE _AC(0x0000000008400000,UL)
#define MODULES_VADDR _AC(0x0000000010000000,UL)
#define MODULES_LEN _AC(0x00000000e0000000,UL)
#define MODULES_END _AC(0x00000000f0000000,UL)
#define LOW_OBP_ADDRESS _AC(0x00000000f0000000,UL)
#define HI_OBP_ADDRESS _AC(0x0000000100000000,UL)
#define VMALLOC_START _AC(0x0000000100000000,UL)
#define VMEMMAP_BASE VMALLOC_END
/* PMD_SHIFT determines the size of the area a second-level page
* table can map
*/
#define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT-3))
#define PMD_SIZE (_AC(1,UL) << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
#define PMD_BITS (PAGE_SHIFT - 3)
/* PUD_SHIFT determines the size of the area a third-level page
* table can map
*/
#define PUD_SHIFT (PMD_SHIFT + PMD_BITS)
#define PUD_SIZE (_AC(1,UL) << PUD_SHIFT)
#define PUD_MASK (~(PUD_SIZE-1))
#define PUD_BITS (PAGE_SHIFT - 3)
/* PGDIR_SHIFT determines what a fourth-level page table entry can map */
#define PGDIR_SHIFT (PUD_SHIFT + PUD_BITS)
#define PGDIR_SIZE (_AC(1,UL) << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
#define PGDIR_BITS (PAGE_SHIFT - 3)
#if (MAX_PHYS_ADDRESS_BITS > PGDIR_SHIFT + PGDIR_BITS)
#error MAX_PHYS_ADDRESS_BITS exceeds what kernel page tables can support
#endif
#if (PGDIR_SHIFT + PGDIR_BITS) != 53
#error Page table parameters do not cover virtual address space properly.
#endif
#if (PMD_SHIFT != HPAGE_SHIFT)
#error PMD_SHIFT must equal HPAGE_SHIFT for transparent huge pages.
#endif
#ifndef __ASSEMBLY__
extern unsigned long VMALLOC_END;
#define vmemmap ((struct page *)VMEMMAP_BASE)
#include <linux/sched.h>
bool kern_addr_valid(unsigned long addr);
/* Entries per page directory level. */
#define PTRS_PER_PTE (1UL << (PAGE_SHIFT-3))
#define PTRS_PER_PMD (1UL << PMD_BITS)
#define PTRS_PER_PUD (1UL << PUD_BITS)
#define PTRS_PER_PGD (1UL << PGDIR_BITS)
#define pmd_ERROR(e) \
pr_err("%s:%d: bad pmd %p(%016lx) seen at (%pS)\n", \
__FILE__, __LINE__, &(e), pmd_val(e), __builtin_return_address(0))
#define pud_ERROR(e) \
pr_err("%s:%d: bad pud %p(%016lx) seen at (%pS)\n", \
__FILE__, __LINE__, &(e), pud_val(e), __builtin_return_address(0))
#define pgd_ERROR(e) \
pr_err("%s:%d: bad pgd %p(%016lx) seen at (%pS)\n", \
__FILE__, __LINE__, &(e), pgd_val(e), __builtin_return_address(0))
#endif /* !(__ASSEMBLY__) */
/* PTE bits which are the same in SUN4U and SUN4V format. */
#define _PAGE_VALID _AC(0x8000000000000000,UL) /* Valid TTE */
#define _PAGE_R _AC(0x8000000000000000,UL) /* Keep ref bit uptodate*/
#define _PAGE_SPECIAL _AC(0x0200000000000000,UL) /* Special page */
#define _PAGE_PMD_HUGE _AC(0x0100000000000000,UL) /* Huge page */
#define _PAGE_PUD_HUGE _PAGE_PMD_HUGE
/* SUN4U pte bits... */
#define _PAGE_SZ4MB_4U _AC(0x6000000000000000,UL) /* 4MB Page */
#define _PAGE_SZ512K_4U _AC(0x4000000000000000,UL) /* 512K Page */
#define _PAGE_SZ64K_4U _AC(0x2000000000000000,UL) /* 64K Page */
#define _PAGE_SZ8K_4U _AC(0x0000000000000000,UL) /* 8K Page */
#define _PAGE_NFO_4U _AC(0x1000000000000000,UL) /* No Fault Only */
#define _PAGE_IE_4U _AC(0x0800000000000000,UL) /* Invert Endianness */
#define _PAGE_SOFT2_4U _AC(0x07FC000000000000,UL) /* Software bits, set 2 */
#define _PAGE_SPECIAL_4U _AC(0x0200000000000000,UL) /* Special page */
#define _PAGE_PMD_HUGE_4U _AC(0x0100000000000000,UL) /* Huge page */
#define _PAGE_RES1_4U _AC(0x0002000000000000,UL) /* Reserved */
#define _PAGE_SZ32MB_4U _AC(0x0001000000000000,UL) /* (Panther) 32MB page */
#define _PAGE_SZ256MB_4U _AC(0x2001000000000000,UL) /* (Panther) 256MB page */
#define _PAGE_SZALL_4U _AC(0x6001000000000000,UL) /* All pgsz bits */
#define _PAGE_SN_4U _AC(0x0000800000000000,UL) /* (Cheetah) Snoop */
#define _PAGE_RES2_4U _AC(0x0000780000000000,UL) /* Reserved */
#define _PAGE_PADDR_4U _AC(0x000007FFFFFFE000,UL) /* (Cheetah) pa[42:13] */
#define _PAGE_SOFT_4U _AC(0x0000000000001F80,UL) /* Software bits: */
#define _PAGE_EXEC_4U _AC(0x0000000000001000,UL) /* Executable SW bit */
#define _PAGE_MODIFIED_4U _AC(0x0000000000000800,UL) /* Modified (dirty) */
#define _PAGE_ACCESSED_4U _AC(0x0000000000000400,UL) /* Accessed (ref'd) */
#define _PAGE_READ_4U _AC(0x0000000000000200,UL) /* Readable SW Bit */
#define _PAGE_WRITE_4U _AC(0x0000000000000100,UL) /* Writable SW Bit */
#define _PAGE_PRESENT_4U _AC(0x0000000000000080,UL) /* Present */
#define _PAGE_L_4U _AC(0x0000000000000040,UL) /* Locked TTE */
#define _PAGE_CP_4U _AC(0x0000000000000020,UL) /* Cacheable in P-Cache */
#define _PAGE_CV_4U _AC(0x0000000000000010,UL) /* Cacheable in V-Cache */
#define _PAGE_E_4U _AC(0x0000000000000008,UL) /* side-Effect */
#define _PAGE_P_4U _AC(0x0000000000000004,UL) /* Privileged Page */
#define _PAGE_W_4U _AC(0x0000000000000002,UL) /* Writable */
/* SUN4V pte bits... */
#define _PAGE_NFO_4V _AC(0x4000000000000000,UL) /* No Fault Only */
#define _PAGE_SOFT2_4V _AC(0x3F00000000000000,UL) /* Software bits, set 2 */
#define _PAGE_MODIFIED_4V _AC(0x2000000000000000,UL) /* Modified (dirty) */
#define _PAGE_ACCESSED_4V _AC(0x1000000000000000,UL) /* Accessed (ref'd) */
#define _PAGE_READ_4V _AC(0x0800000000000000,UL) /* Readable SW Bit */
#define _PAGE_WRITE_4V _AC(0x0400000000000000,UL) /* Writable SW Bit */
#define _PAGE_SPECIAL_4V _AC(0x0200000000000000,UL) /* Special page */
#define _PAGE_PMD_HUGE_4V _AC(0x0100000000000000,UL) /* Huge page */
#define _PAGE_PADDR_4V _AC(0x00FFFFFFFFFFE000,UL) /* paddr[55:13] */
#define _PAGE_IE_4V _AC(0x0000000000001000,UL) /* Invert Endianness */
#define _PAGE_E_4V _AC(0x0000000000000800,UL) /* side-Effect */
#define _PAGE_CP_4V _AC(0x0000000000000400,UL) /* Cacheable in P-Cache */
#define _PAGE_CV_4V _AC(0x0000000000000200,UL) /* Cacheable in V-Cache */
/* Bit 9 is used to enable MCD corruption detection instead on M7 */
#define _PAGE_MCD_4V _AC(0x0000000000000200,UL) /* Memory Corruption */
#define _PAGE_P_4V _AC(0x0000000000000100,UL) /* Privileged Page */
#define _PAGE_EXEC_4V _AC(0x0000000000000080,UL) /* Executable Page */
#define _PAGE_W_4V _AC(0x0000000000000040,UL) /* Writable */
#define _PAGE_SOFT_4V _AC(0x0000000000000030,UL) /* Software bits */
#define _PAGE_PRESENT_4V _AC(0x0000000000000010,UL) /* Present */
#define _PAGE_RESV_4V _AC(0x0000000000000008,UL) /* Reserved */
#define _PAGE_SZ16GB_4V _AC(0x0000000000000007,UL) /* 16GB Page */
#define _PAGE_SZ2GB_4V _AC(0x0000000000000006,UL) /* 2GB Page */
#define _PAGE_SZ256MB_4V _AC(0x0000000000000005,UL) /* 256MB Page */
#define _PAGE_SZ32MB_4V _AC(0x0000000000000004,UL) /* 32MB Page */
#define _PAGE_SZ4MB_4V _AC(0x0000000000000003,UL) /* 4MB Page */
#define _PAGE_SZ512K_4V _AC(0x0000000000000002,UL) /* 512K Page */
#define _PAGE_SZ64K_4V _AC(0x0000000000000001,UL) /* 64K Page */
#define _PAGE_SZ8K_4V _AC(0x0000000000000000,UL) /* 8K Page */
#define _PAGE_SZALL_4V _AC(0x0000000000000007,UL) /* All pgsz bits */
#define _PAGE_SZBITS_4U _PAGE_SZ8K_4U
#define _PAGE_SZBITS_4V _PAGE_SZ8K_4V
#if REAL_HPAGE_SHIFT != 22
#error REAL_HPAGE_SHIFT and _PAGE_SZHUGE_foo must match up
#endif
#define _PAGE_SZHUGE_4U _PAGE_SZ4MB_4U
#define _PAGE_SZHUGE_4V _PAGE_SZ4MB_4V
/* We borrow bit 20 to store the exclusive marker in swap PTEs. */
#define _PAGE_SWP_EXCLUSIVE _AC(0x0000000000100000, UL)
#ifndef __ASSEMBLY__
pte_t mk_pte_io(unsigned long, pgprot_t, int, unsigned long);
unsigned long pte_sz_bits(unsigned long size);
extern pgprot_t PAGE_KERNEL;
extern pgprot_t PAGE_KERNEL_LOCKED;
extern pgprot_t PAGE_COPY;
extern pgprot_t PAGE_SHARED;
/* XXX This ugliness is for the atyfb driver's sparc mmap() support. XXX */
extern unsigned long _PAGE_IE;
extern unsigned long _PAGE_E;
extern unsigned long _PAGE_CACHE;
extern unsigned long pg_iobits;
extern unsigned long _PAGE_ALL_SZ_BITS;
extern struct page *mem_map_zero;
#define ZERO_PAGE(vaddr) (mem_map_zero)
/* PFNs are real physical page numbers. However, mem_map only begins to record
* per-page information starting at pfn_base. This is to handle systems where
* the first physical page in the machine is at some huge physical address,
* such as 4GB. This is common on a partitioned E10000, for example.
*/
static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot)
{
unsigned long paddr = pfn << PAGE_SHIFT;
BUILD_BUG_ON(_PAGE_SZBITS_4U != 0UL || _PAGE_SZBITS_4V != 0UL);
return __pte(paddr | pgprot_val(prot));
}
#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static inline pmd_t pfn_pmd(unsigned long page_nr, pgprot_t pgprot)
{
pte_t pte = pfn_pte(page_nr, pgprot);
return __pmd(pte_val(pte));
}
#define mk_pmd(page, pgprot) pfn_pmd(page_to_pfn(page), (pgprot))
#endif
/* This one can be done with two shifts. */
static inline unsigned long pte_pfn(pte_t pte)
{
unsigned long ret;
__asm__ __volatile__(
"\n661: sllx %1, %2, %0\n"
" srlx %0, %3, %0\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sllx %1, %4, %0\n"
" srlx %0, %5, %0\n"
" .previous\n"
: "=r" (ret)
: "r" (pte_val(pte)),
"i" (21), "i" (21 + PAGE_SHIFT),
"i" (8), "i" (8 + PAGE_SHIFT));
return ret;
}
#define pte_page(x) pfn_to_page(pte_pfn(x))
static inline pte_t pte_modify(pte_t pte, pgprot_t prot)
{
unsigned long mask, tmp;
/* SUN4U: 0x630107ffffffec38 (negated == 0x9cfef800000013c7)
* SUN4V: 0x33ffffffffffee07 (negated == 0xcc000000000011f8)
*
* Even if we use negation tricks the result is still a 6
* instruction sequence, so don't try to play fancy and just
* do the most straightforward implementation.
*
* Note: We encode this into 3 sun4v 2-insn patch sequences.
*/
BUILD_BUG_ON(_PAGE_SZBITS_4U != 0UL || _PAGE_SZBITS_4V != 0UL);
__asm__ __volatile__(
"\n661: sethi %%uhi(%2), %1\n"
" sethi %%hi(%2), %0\n"
"\n662: or %1, %%ulo(%2), %1\n"
" or %0, %%lo(%2), %0\n"
"\n663: sllx %1, 32, %1\n"
" or %0, %1, %0\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%3), %1\n"
" sethi %%hi(%3), %0\n"
" .word 662b\n"
" or %1, %%ulo(%3), %1\n"
" or %0, %%lo(%3), %0\n"
" .word 663b\n"
" sllx %1, 32, %1\n"
" or %0, %1, %0\n"
" .previous\n"
" .section .sun_m7_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%4), %1\n"
" sethi %%hi(%4), %0\n"
" .word 662b\n"
" or %1, %%ulo(%4), %1\n"
" or %0, %%lo(%4), %0\n"
" .word 663b\n"
" sllx %1, 32, %1\n"
" or %0, %1, %0\n"
" .previous\n"
: "=r" (mask), "=r" (tmp)
: "i" (_PAGE_PADDR_4U | _PAGE_MODIFIED_4U | _PAGE_ACCESSED_4U |
_PAGE_CP_4U | _PAGE_CV_4U | _PAGE_E_4U |
_PAGE_SPECIAL | _PAGE_PMD_HUGE | _PAGE_SZALL_4U),
"i" (_PAGE_PADDR_4V | _PAGE_MODIFIED_4V | _PAGE_ACCESSED_4V |
_PAGE_CP_4V | _PAGE_CV_4V | _PAGE_E_4V |
_PAGE_SPECIAL | _PAGE_PMD_HUGE | _PAGE_SZALL_4V),
"i" (_PAGE_PADDR_4V | _PAGE_MODIFIED_4V | _PAGE_ACCESSED_4V |
_PAGE_CP_4V | _PAGE_E_4V |
_PAGE_SPECIAL | _PAGE_PMD_HUGE | _PAGE_SZALL_4V));
return __pte((pte_val(pte) & mask) | (pgprot_val(prot) & ~mask));
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
{
pte_t pte = __pte(pmd_val(pmd));
pte = pte_modify(pte, newprot);
return __pmd(pte_val(pte));
}
#endif
static inline pgprot_t pgprot_noncached(pgprot_t prot)
{
unsigned long val = pgprot_val(prot);
__asm__ __volatile__(
"\n661: andn %0, %2, %0\n"
" or %0, %3, %0\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" andn %0, %4, %0\n"
" or %0, %5, %0\n"
" .previous\n"
" .section .sun_m7_2insn_patch, \"ax\"\n"
" .word 661b\n"
" andn %0, %6, %0\n"
" or %0, %5, %0\n"
" .previous\n"
: "=r" (val)
: "0" (val), "i" (_PAGE_CP_4U | _PAGE_CV_4U), "i" (_PAGE_E_4U),
"i" (_PAGE_CP_4V | _PAGE_CV_4V), "i" (_PAGE_E_4V),
"i" (_PAGE_CP_4V));
return __pgprot(val);
}
/* Various pieces of code check for platform support by ifdef testing
* on "pgprot_noncached". That's broken and should be fixed, but for
* now...
*/
#define pgprot_noncached pgprot_noncached
static inline unsigned long pte_dirty(pte_t pte)
{
unsigned long mask;
__asm__ __volatile__(
"\n661: mov %1, %0\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%2), %0\n"
" sllx %0, 32, %0\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_MODIFIED_4U), "i" (_PAGE_MODIFIED_4V));
return (pte_val(pte) & mask);
}
static inline unsigned long pte_write(pte_t pte)
{
unsigned long mask;
__asm__ __volatile__(
"\n661: mov %1, %0\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%2), %0\n"
" sllx %0, 32, %0\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_WRITE_4U), "i" (_PAGE_WRITE_4V));
return (pte_val(pte) & mask);
}
#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags);
#define arch_make_huge_pte arch_make_huge_pte
static inline unsigned long __pte_default_huge_mask(void)
{
unsigned long mask;
__asm__ __volatile__(
"\n661: sethi %%uhi(%1), %0\n"
" sllx %0, 32, %0\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" mov %2, %0\n"
" nop\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_SZHUGE_4U), "i" (_PAGE_SZHUGE_4V));
return mask;
}
static inline pte_t pte_mkhuge(pte_t pte)
{
return __pte(pte_val(pte) | __pte_default_huge_mask());
}
static inline bool is_default_hugetlb_pte(pte_t pte)
{
unsigned long mask = __pte_default_huge_mask();
return (pte_val(pte) & mask) == mask;
}
static inline bool is_hugetlb_pmd(pmd_t pmd)
{
return !!(pmd_val(pmd) & _PAGE_PMD_HUGE);
}
static inline bool is_hugetlb_pud(pud_t pud)
{
return !!(pud_val(pud) & _PAGE_PUD_HUGE);
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static inline pmd_t pmd_mkhuge(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
pte = pte_mkhuge(pte);
pte_val(pte) |= _PAGE_PMD_HUGE;
return __pmd(pte_val(pte));
}
#endif
#else
static inline bool is_hugetlb_pte(pte_t pte)
{
return false;
}
#endif
static inline pte_t __pte_mkhwwrite(pte_t pte)
{
unsigned long val = pte_val(pte);
/*
* Note: we only want to set the HW writable bit if the SW writable bit
* and the SW dirty bit are set.
*/
__asm__ __volatile__(
"\n661: or %0, %2, %0\n"
" .section .sun4v_1insn_patch, \"ax\"\n"
" .word 661b\n"
" or %0, %3, %0\n"
" .previous\n"
: "=r" (val)
: "0" (val), "i" (_PAGE_W_4U), "i" (_PAGE_W_4V));
return __pte(val);
}
static inline pte_t pte_mkdirty(pte_t pte)
{
unsigned long val = pte_val(pte), mask;
__asm__ __volatile__(
"\n661: mov %1, %0\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%2), %0\n"
" sllx %0, 32, %0\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_MODIFIED_4U), "i" (_PAGE_MODIFIED_4V));
pte = __pte(val | mask);
return pte_write(pte) ? __pte_mkhwwrite(pte) : pte;
}
static inline pte_t pte_mkclean(pte_t pte)
{
unsigned long val = pte_val(pte), tmp;
__asm__ __volatile__(
"\n661: andn %0, %3, %0\n"
" nop\n"
"\n662: nop\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%4), %1\n"
" sllx %1, 32, %1\n"
" .word 662b\n"
" or %1, %%lo(%4), %1\n"
" andn %0, %1, %0\n"
" .previous\n"
: "=r" (val), "=r" (tmp)
: "0" (val), "i" (_PAGE_MODIFIED_4U | _PAGE_W_4U),
"i" (_PAGE_MODIFIED_4V | _PAGE_W_4V));
return __pte(val);
}
static inline pte_t pte_mkwrite(pte_t pte)
{
unsigned long val = pte_val(pte), mask;
__asm__ __volatile__(
"\n661: mov %1, %0\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%2), %0\n"
" sllx %0, 32, %0\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_WRITE_4U), "i" (_PAGE_WRITE_4V));
pte = __pte(val | mask);
return pte_dirty(pte) ? __pte_mkhwwrite(pte) : pte;
}
static inline pte_t pte_wrprotect(pte_t pte)
{
unsigned long val = pte_val(pte), tmp;
__asm__ __volatile__(
"\n661: andn %0, %3, %0\n"
" nop\n"
"\n662: nop\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%4), %1\n"
" sllx %1, 32, %1\n"
" .word 662b\n"
" or %1, %%lo(%4), %1\n"
" andn %0, %1, %0\n"
" .previous\n"
: "=r" (val), "=r" (tmp)
: "0" (val), "i" (_PAGE_WRITE_4U | _PAGE_W_4U),
"i" (_PAGE_WRITE_4V | _PAGE_W_4V));
return __pte(val);
}
static inline pte_t pte_mkold(pte_t pte)
{
unsigned long mask;
__asm__ __volatile__(
"\n661: mov %1, %0\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%2), %0\n"
" sllx %0, 32, %0\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_ACCESSED_4U), "i" (_PAGE_ACCESSED_4V));
mask |= _PAGE_R;
return __pte(pte_val(pte) & ~mask);
}
static inline pte_t pte_mkyoung(pte_t pte)
{
unsigned long mask;
__asm__ __volatile__(
"\n661: mov %1, %0\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%2), %0\n"
" sllx %0, 32, %0\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_ACCESSED_4U), "i" (_PAGE_ACCESSED_4V));
mask |= _PAGE_R;
return __pte(pte_val(pte) | mask);
}
static inline pte_t pte_mkspecial(pte_t pte)
{
pte_val(pte) |= _PAGE_SPECIAL;
return pte;
}
static inline pte_t pte_mkmcd(pte_t pte)
{
pte_val(pte) |= _PAGE_MCD_4V;
return pte;
}
static inline pte_t pte_mknotmcd(pte_t pte)
{
pte_val(pte) &= ~_PAGE_MCD_4V;
return pte;
}
static inline unsigned long pte_young(pte_t pte)
{
unsigned long mask;
__asm__ __volatile__(
"\n661: mov %1, %0\n"
" nop\n"
" .section .sun4v_2insn_patch, \"ax\"\n"
" .word 661b\n"
" sethi %%uhi(%2), %0\n"
" sllx %0, 32, %0\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_ACCESSED_4U), "i" (_PAGE_ACCESSED_4V));
return (pte_val(pte) & mask);
}
static inline unsigned long pte_exec(pte_t pte)
{
unsigned long mask;
__asm__ __volatile__(
"\n661: sethi %%hi(%1), %0\n"
" .section .sun4v_1insn_patch, \"ax\"\n"
" .word 661b\n"
" mov %2, %0\n"
" .previous\n"
: "=r" (mask)
: "i" (_PAGE_EXEC_4U), "i" (_PAGE_EXEC_4V));
return (pte_val(pte) & mask);
}
static inline unsigned long pte_present(pte_t pte)
{
unsigned long val = pte_val(pte);
__asm__ __volatile__(
"\n661: and %0, %2, %0\n"
" .section .sun4v_1insn_patch, \"ax\"\n"
" .word 661b\n"
" and %0, %3, %0\n"
" .previous\n"
: "=r" (val)
: "0" (val), "i" (_PAGE_PRESENT_4U), "i" (_PAGE_PRESENT_4V));
return val;
}
#define pte_accessible pte_accessible
static inline unsigned long pte_accessible(struct mm_struct *mm, pte_t a)
{
return pte_val(a) & _PAGE_VALID;
}
static inline unsigned long pte_special(pte_t pte)
{
return pte_val(pte) & _PAGE_SPECIAL;
}
#define pmd_leaf pmd_large
static inline unsigned long pmd_large(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
return pte_val(pte) & _PAGE_PMD_HUGE;
}
static inline unsigned long pmd_pfn(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
return pte_pfn(pte);
}
#define pmd_write pmd_write
static inline unsigned long pmd_write(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
return pte_write(pte);
}
#define pud_write(pud) pte_write(__pte(pud_val(pud)))
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static inline unsigned long pmd_dirty(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
return pte_dirty(pte);
}
#define pmd_young pmd_young
static inline unsigned long pmd_young(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
return pte_young(pte);
}
static inline unsigned long pmd_trans_huge(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
return pte_val(pte) & _PAGE_PMD_HUGE;
}
static inline pmd_t pmd_mkold(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
pte = pte_mkold(pte);
return __pmd(pte_val(pte));
}
static inline pmd_t pmd_wrprotect(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
pte = pte_wrprotect(pte);
return __pmd(pte_val(pte));
}
static inline pmd_t pmd_mkdirty(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
pte = pte_mkdirty(pte);
return __pmd(pte_val(pte));
}
static inline pmd_t pmd_mkclean(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
pte = pte_mkclean(pte);
return __pmd(pte_val(pte));
}
static inline pmd_t pmd_mkyoung(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
pte = pte_mkyoung(pte);
return __pmd(pte_val(pte));
}
static inline pmd_t pmd_mkwrite(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
pte = pte_mkwrite(pte);
return __pmd(pte_val(pte));
}
static inline pgprot_t pmd_pgprot(pmd_t entry)
{
unsigned long val = pmd_val(entry);
return __pgprot(val);
}
#endif
static inline int pmd_present(pmd_t pmd)
{
return pmd_val(pmd) != 0UL;
}
#define pmd_none(pmd) (!pmd_val(pmd))
/* pmd_bad() is only called on non-trans-huge PMDs. Our encoding is
* very simple, it's just the physical address. PTE tables are of
* size PAGE_SIZE so make sure the sub-PAGE_SIZE bits are clear and
* the top bits outside of the range of any physical address size we
* support are clear as well. We also validate the physical itself.
*/
#define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK)
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) (pud_val(pud) & ~PAGE_MASK)
#define p4d_none(p4d) (!p4d_val(p4d))
#define p4d_bad(p4d) (p4d_val(p4d) & ~PAGE_MASK)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
void set_pmd_at(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t pmd);
#else
static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t pmd)
{
*pmdp = pmd;
}
#endif
static inline void pmd_set(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
{
unsigned long val = __pa((unsigned long) (ptep));
pmd_val(*pmdp) = val;
}
#define pud_set(pudp, pmdp) \
(pud_val(*(pudp)) = (__pa((unsigned long) (pmdp))))
static inline unsigned long pmd_page_vaddr(pmd_t pmd)
{
pte_t pte = __pte(pmd_val(pmd));
unsigned long pfn;
pfn = pte_pfn(pte);
return ((unsigned long) __va(pfn << PAGE_SHIFT));
}
static inline pmd_t *pud_pgtable(pud_t pud)
{
pte_t pte = __pte(pud_val(pud));
unsigned long pfn;
pfn = pte_pfn(pte);
return ((pmd_t *) __va(pfn << PAGE_SHIFT));
}
#define pmd_page(pmd) virt_to_page((void *)pmd_page_vaddr(pmd))
#define pud_page(pud) virt_to_page((void *)pud_pgtable(pud))
#define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0UL)
#define pud_present(pud) (pud_val(pud) != 0U)
#define pud_clear(pudp) (pud_val(*(pudp)) = 0UL)
#define p4d_pgtable(p4d) \
((pud_t *) __va(p4d_val(p4d)))
#define p4d_present(p4d) (p4d_val(p4d) != 0U)
#define p4d_clear(p4dp) (p4d_val(*(p4dp)) = 0UL)
/* only used by the stubbed out hugetlb gup code, should never be called */
#define p4d_page(p4d) NULL
#define pud_leaf pud_large
static inline unsigned long pud_large(pud_t pud)
{
pte_t pte = __pte(pud_val(pud));
return pte_val(pte) & _PAGE_PMD_HUGE;
}
static inline unsigned long pud_pfn(pud_t pud)
{
pte_t pte = __pte(pud_val(pud));
return pte_pfn(pte);
}
/* Same in both SUN4V and SUN4U. */
#define pte_none(pte) (!pte_val(pte))
#define p4d_set(p4dp, pudp) \
(p4d_val(*(p4dp)) = (__pa((unsigned long) (pudp))))
/* We cannot include <linux/mm_types.h> at this point yet: */
extern struct mm_struct init_mm;
/* Actual page table PTE updates. */
void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
pte_t *ptep, pte_t orig, int fullmm,
unsigned int hugepage_shift);
static void maybe_tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
pte_t *ptep, pte_t orig, int fullmm,
unsigned int hugepage_shift)
{
/* It is more efficient to let flush_tlb_kernel_range()
* handle init_mm tlb flushes.
*
* SUN4V NOTE: _PAGE_VALID is the same value in both the SUN4U
* and SUN4V pte layout, so this inline test is fine.
*/
if (likely(mm != &init_mm) && pte_accessible(mm, orig))
tlb_batch_add(mm, vaddr, ptep, orig, fullmm, hugepage_shift);
}
#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
unsigned long addr,
pmd_t *pmdp)
{
pmd_t pmd = *pmdp;
set_pmd_at(mm, addr, pmdp, __pmd(0UL));
return pmd;
}
static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte, int fullmm)
{
pte_t orig = *ptep;
*ptep = pte;
maybe_tlb_batch_add(mm, addr, ptep, orig, fullmm, PAGE_SHIFT);
}
#define set_pte_at(mm,addr,ptep,pte) \
__set_pte_at((mm), (addr), (ptep), (pte), 0)
#define pte_clear(mm,addr,ptep) \
set_pte_at((mm), (addr), (ptep), __pte(0UL))
#define __HAVE_ARCH_PTE_CLEAR_NOT_PRESENT_FULL
#define pte_clear_not_present_full(mm,addr,ptep,fullmm) \
__set_pte_at((mm), (addr), (ptep), __pte(0UL), (fullmm))
#ifdef DCACHE_ALIASING_POSSIBLE
#define __HAVE_ARCH_MOVE_PTE
#define move_pte(pte, prot, old_addr, new_addr) \
({ \
pte_t newpte = (pte); \
if (tlb_type != hypervisor && pte_present(pte)) { \
unsigned long this_pfn = pte_pfn(pte); \
\
if (pfn_valid(this_pfn) && \
(((old_addr) ^ (new_addr)) & (1 << 13))) \
flush_dcache_page_all(current->mm, \
pfn_to_page(this_pfn)); \
} \
newpte; \
})
#endif
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
void paging_init(void);
unsigned long find_ecache_flush_span(unsigned long size);
struct seq_file;
void mmu_info(struct seq_file *);
struct vm_area_struct;
void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr,
pmd_t *pmd);
#define __HAVE_ARCH_PMDP_INVALIDATE
extern pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
pmd_t *pmdp);
#define __HAVE_ARCH_PGTABLE_DEPOSIT
void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
pgtable_t pgtable);
#define __HAVE_ARCH_PGTABLE_WITHDRAW
pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
#endif
/*
* Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
* are !pte_none() && !pte_present().
*
* Format of swap PTEs:
*
* 6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3
* 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2
* <--------------------------- offset ---------------------------
*
* 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
* --------------------> E <-- type ---> <------- zeroes -------->
*/
#define __swp_type(entry) (((entry).val >> PAGE_SHIFT) & 0x7fUL)
#define __swp_offset(entry) ((entry).val >> (PAGE_SHIFT + 8UL))
#define __swp_entry(type, offset) \
( (swp_entry_t) \
{ \
((((long)(type) & 0x7fUL) << PAGE_SHIFT) | \
((long)(offset) << (PAGE_SHIFT + 8UL))) \
} )
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
static inline int pte_swp_exclusive(pte_t pte)
{
return pte_val(pte) & _PAGE_SWP_EXCLUSIVE;
}
static inline pte_t pte_swp_mkexclusive(pte_t pte)
{
return __pte(pte_val(pte) | _PAGE_SWP_EXCLUSIVE);
}
static inline pte_t pte_swp_clear_exclusive(pte_t pte)
{
return __pte(pte_val(pte) & ~_PAGE_SWP_EXCLUSIVE);
}
int page_in_phys_avail(unsigned long paddr);
/*
* For sparc32&64, the pfn in io_remap_pfn_range() carries <iospace> in
* its high 4 bits. These macros/functions put it there or get it from there.
*/
#define MK_IOSPACE_PFN(space, pfn) (pfn | (space << (BITS_PER_LONG - 4)))
#define GET_IOSPACE(pfn) (pfn >> (BITS_PER_LONG - 4))
#define GET_PFN(pfn) (pfn & 0x0fffffffffffffffUL)
int remap_pfn_range(struct vm_area_struct *, unsigned long, unsigned long,
unsigned long, pgprot_t);
void adi_restore_tags(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pte_t pte);
int adi_save_tags(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pte_t oldpte);
#define __HAVE_ARCH_DO_SWAP_PAGE
static inline void arch_do_swap_page(struct mm_struct *mm,
struct vm_area_struct *vma,
unsigned long addr,
pte_t pte, pte_t oldpte)
{
/* If this is a new page being mapped in, there can be no
* ADI tags stored away for this page. Skip looking for
* stored tags
*/
if (pte_none(oldpte))
return;
if (adi_state.enabled && (pte_val(pte) & _PAGE_MCD_4V))
adi_restore_tags(mm, vma, addr, pte);
}
#define __HAVE_ARCH_UNMAP_ONE
static inline int arch_unmap_one(struct mm_struct *mm,
struct vm_area_struct *vma,
unsigned long addr, pte_t oldpte)
{
if (adi_state.enabled && (pte_val(oldpte) & _PAGE_MCD_4V))
return adi_save_tags(mm, vma, addr, oldpte);
return 0;
}
static inline int io_remap_pfn_range(struct vm_area_struct *vma,
unsigned long from, unsigned long pfn,
unsigned long size, pgprot_t prot)
{
unsigned long offset = GET_PFN(pfn) << PAGE_SHIFT;
int space = GET_IOSPACE(pfn);
unsigned long phys_base;
phys_base = offset | (((unsigned long) space) << 32UL);
return remap_pfn_range(vma, from, phys_base >> PAGE_SHIFT, size, prot);
}
#define io_remap_pfn_range io_remap_pfn_range
static inline unsigned long __untagged_addr(unsigned long start)
{
if (adi_capable()) {
long addr = start;
/* If userspace has passed a versioned address, kernel
* will not find it in the VMAs since it does not store
* the version tags in the list of VMAs. Storing version
* tags in list of VMAs is impractical since they can be
* changed any time from userspace without dropping into
* kernel. Any address search in VMAs will be done with
* non-versioned addresses. Ensure the ADI version bits
* are dropped here by sign extending the last bit before
* ADI bits. IOMMU does not implement version tags.
*/
return (addr << (long)adi_nbits()) >> (long)adi_nbits();
}
return start;
}
#define untagged_addr(addr) \
((__typeof__(addr))(__untagged_addr((unsigned long)(addr))))
static inline bool pte_access_permitted(pte_t pte, bool write)
{
u64 prot;
if (tlb_type == hypervisor) {
prot = _PAGE_PRESENT_4V | _PAGE_P_4V;
if (write)
prot |= _PAGE_WRITE_4V;
} else {
prot = _PAGE_PRESENT_4U | _PAGE_P_4U;
if (write)
prot |= _PAGE_WRITE_4U;
}
return (pte_val(pte) & (prot | _PAGE_SPECIAL)) == prot;
}
#define pte_access_permitted pte_access_permitted
#include <asm/tlbflush.h>
/* We provide our own get_unmapped_area to cope with VA holes and
* SHM area cache aliasing for userland.
*/
#define HAVE_ARCH_UNMAPPED_AREA
#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
/* We provide a special get_unmapped_area for framebuffer mmaps to try and use
* the largest alignment possible such that larget PTEs can be used.
*/
unsigned long get_fb_unmapped_area(struct file *filp, unsigned long,
unsigned long, unsigned long,
unsigned long);
#define HAVE_ARCH_FB_UNMAPPED_AREA
void sun4v_register_fault_status(void);
void sun4v_ktsb_register(void);
void __init cheetah_ecache_flush_init(void);
void sun4v_patch_tlb_handlers(void);
extern unsigned long cmdline_memory_size;
asmlinkage void do_sparc64_fault(struct pt_regs *regs);
#define pmd_pgtable(PMD) ((pte_t *)pmd_page_vaddr(PMD))
#ifdef CONFIG_HUGETLB_PAGE
#define pud_leaf_size pud_leaf_size
extern unsigned long pud_leaf_size(pud_t pud);
#define pmd_leaf_size pmd_leaf_size
extern unsigned long pmd_leaf_size(pmd_t pmd);
#define pte_leaf_size pte_leaf_size
extern unsigned long pte_leaf_size(pte_t pte);
#endif /* CONFIG_HUGETLB_PAGE */
#endif /* !(__ASSEMBLY__) */
#endif /* !(_SPARC64_PGTABLE_H) */
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