linux-stable/include/linux/pfn_t.h
Laurent Dufour 3010a5ea66 mm: introduce ARCH_HAS_PTE_SPECIAL
Currently the PTE special supports is turned on in per architecture
header files.  Most of the time, it is defined in
arch/*/include/asm/pgtable.h depending or not on some other per
architecture static definition.

This patch introduce a new configuration variable to manage this
directly in the Kconfig files.  It would later replace
__HAVE_ARCH_PTE_SPECIAL.

Here notes for some architecture where the definition of
__HAVE_ARCH_PTE_SPECIAL is not obvious:

arm
 __HAVE_ARCH_PTE_SPECIAL which is currently defined in
arch/arm/include/asm/pgtable-3level.h which is included by
arch/arm/include/asm/pgtable.h when CONFIG_ARM_LPAE is set.
So select ARCH_HAS_PTE_SPECIAL if ARM_LPAE.

powerpc
__HAVE_ARCH_PTE_SPECIAL is defined in 2 files:
 - arch/powerpc/include/asm/book3s/64/pgtable.h
 - arch/powerpc/include/asm/pte-common.h
The first one is included if (PPC_BOOK3S & PPC64) while the second is
included in all the other cases.
So select ARCH_HAS_PTE_SPECIAL all the time.

sparc:
__HAVE_ARCH_PTE_SPECIAL is defined if defined(__sparc__) &&
defined(__arch64__) which are defined through the compiler in
sparc/Makefile if !SPARC32 which I assume to be if SPARC64.
So select ARCH_HAS_PTE_SPECIAL if SPARC64

There is no functional change introduced by this patch.

Link: http://lkml.kernel.org/r/1523433816-14460-2-git-send-email-ldufour@linux.vnet.ibm.com
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Suggested-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Christophe LEROY <christophe.leroy@c-s.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07 17:34:35 -07:00

136 lines
3.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_PFN_T_H_
#define _LINUX_PFN_T_H_
#include <linux/mm.h>
/*
* PFN_FLAGS_MASK - mask of all the possible valid pfn_t flags
* PFN_SG_CHAIN - pfn is a pointer to the next scatterlist entry
* PFN_SG_LAST - pfn references a page and is the last scatterlist entry
* PFN_DEV - pfn is not covered by system memmap by default
* PFN_MAP - pfn has a dynamic page mapping established by a device driver
*/
#define PFN_FLAGS_MASK (((u64) ~PAGE_MASK) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
#define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1))
#define PFN_SG_LAST (1ULL << (BITS_PER_LONG_LONG - 2))
#define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3))
#define PFN_MAP (1ULL << (BITS_PER_LONG_LONG - 4))
#define PFN_SPECIAL (1ULL << (BITS_PER_LONG_LONG - 5))
#define PFN_FLAGS_TRACE \
{ PFN_SPECIAL, "SPECIAL" }, \
{ PFN_SG_CHAIN, "SG_CHAIN" }, \
{ PFN_SG_LAST, "SG_LAST" }, \
{ PFN_DEV, "DEV" }, \
{ PFN_MAP, "MAP" }
static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags)
{
pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
return pfn_t;
}
/* a default pfn to pfn_t conversion assumes that @pfn is pfn_valid() */
static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
{
return __pfn_to_pfn_t(pfn, 0);
}
static inline pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
{
return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
}
static inline bool pfn_t_has_page(pfn_t pfn)
{
return (pfn.val & PFN_MAP) == PFN_MAP || (pfn.val & PFN_DEV) == 0;
}
static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
{
return pfn.val & ~PFN_FLAGS_MASK;
}
static inline struct page *pfn_t_to_page(pfn_t pfn)
{
if (pfn_t_has_page(pfn))
return pfn_to_page(pfn_t_to_pfn(pfn));
return NULL;
}
static inline phys_addr_t pfn_t_to_phys(pfn_t pfn)
{
return PFN_PHYS(pfn_t_to_pfn(pfn));
}
static inline void *pfn_t_to_virt(pfn_t pfn)
{
if (pfn_t_has_page(pfn))
return __va(pfn_t_to_phys(pfn));
return NULL;
}
static inline pfn_t page_to_pfn_t(struct page *page)
{
return pfn_to_pfn_t(page_to_pfn(page));
}
static inline int pfn_t_valid(pfn_t pfn)
{
return pfn_valid(pfn_t_to_pfn(pfn));
}
#ifdef CONFIG_MMU
static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
{
return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
}
#endif
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot)
{
return pfn_pmd(pfn_t_to_pfn(pfn), pgprot);
}
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
static inline pud_t pfn_t_pud(pfn_t pfn, pgprot_t pgprot)
{
return pfn_pud(pfn_t_to_pfn(pfn), pgprot);
}
#endif
#endif
#ifdef __HAVE_ARCH_PTE_DEVMAP
static inline bool pfn_t_devmap(pfn_t pfn)
{
const u64 flags = PFN_DEV|PFN_MAP;
return (pfn.val & flags) == flags;
}
#else
static inline bool pfn_t_devmap(pfn_t pfn)
{
return false;
}
pte_t pte_mkdevmap(pte_t pte);
pmd_t pmd_mkdevmap(pmd_t pmd);
#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
pud_t pud_mkdevmap(pud_t pud);
#endif
#endif /* __HAVE_ARCH_PTE_DEVMAP */
#ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
static inline bool pfn_t_special(pfn_t pfn)
{
return (pfn.val & PFN_SPECIAL) == PFN_SPECIAL;
}
#else
static inline bool pfn_t_special(pfn_t pfn)
{
return false;
}
#endif /* CONFIG_ARCH_HAS_PTE_SPECIAL */
#endif /* _LINUX_PFN_T_H_ */