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author | Anshuman Khandual <anshuman.khandual@arm.com> | 2019-07-16 16:27:33 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-16 19:23:22 -0700 |
commit | 0f472d04f59ff89d15b2a1c4eafde7317ddd67a2 (patch) | |
tree | 20786684171109ec50859a88c6a354e12e2a8390 | |
parent | 6b95ab4218bfa59bc315105127ffe03aef3b5742 (diff) | |
download | linux-0f472d04f59ff89d15b2a1c4eafde7317ddd67a2.tar.gz linux-0f472d04f59ff89d15b2a1c4eafde7317ddd67a2.tar.bz2 linux-0f472d04f59ff89d15b2a1c4eafde7317ddd67a2.zip |
mm/ioremap: probe platform for p4d huge map support
Finish up what commit c2febafc6773 ("mm: convert generic code to 5-level
paging") started while levelling up P4D huge mapping support at par with
PUD and PMD. A new arch call back arch_ioremap_p4d_supported() is added
which just maintains status quo (P4D huge map not supported) on x86,
arm64 and powerpc.
When HAVE_ARCH_HUGE_VMAP is enabled its just a simple check from the
arch about the support, hence runtime effects are minimal.
Link: http://lkml.kernel.org/r/1561699231-20991-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | arch/arm64/mm/mmu.c | 5 | ||||
-rw-r--r-- | arch/powerpc/mm/book3s64/radix_pgtable.c | 5 | ||||
-rw-r--r-- | arch/x86/mm/ioremap.c | 5 | ||||
-rw-r--r-- | include/linux/io.h | 1 | ||||
-rw-r--r-- | lib/ioremap.c | 2 |
5 files changed, 18 insertions, 0 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 1b49c08dfa2b..e661469cabdd 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -942,6 +942,11 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys) return dt_virt; } +int __init arch_ioremap_p4d_supported(void) +{ + return 0; +} + int __init arch_ioremap_pud_supported(void) { /* diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c index 65c2ba1e1783..b4ca9e95e678 100644 --- a/arch/powerpc/mm/book3s64/radix_pgtable.c +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c @@ -1237,3 +1237,8 @@ int radix__ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size, return 0; } } + +int __init arch_ioremap_p4d_supported(void) +{ + return 0; +} diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index e500f1df1140..63e99f15d7cf 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -459,6 +459,11 @@ void iounmap(volatile void __iomem *addr) } EXPORT_SYMBOL(iounmap); +int __init arch_ioremap_p4d_supported(void) +{ + return 0; +} + int __init arch_ioremap_pud_supported(void) { #ifdef CONFIG_X86_64 diff --git a/include/linux/io.h b/include/linux/io.h index 9876e5801a9d..accac822336a 100644 --- a/include/linux/io.h +++ b/include/linux/io.h @@ -33,6 +33,7 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end, #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP void __init ioremap_huge_init(void); +int arch_ioremap_p4d_supported(void); int arch_ioremap_pud_supported(void); int arch_ioremap_pmd_supported(void); #else diff --git a/lib/ioremap.c b/lib/ioremap.c index a95161d9c883..0a2ffadc6d71 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -30,6 +30,8 @@ early_param("nohugeiomap", set_nohugeiomap); void __init ioremap_huge_init(void) { if (!ioremap_huge_disabled) { + if (arch_ioremap_p4d_supported()) + ioremap_p4d_capable = 1; if (arch_ioremap_pud_supported()) ioremap_pud_capable = 1; if (arch_ioremap_pmd_supported()) |