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| author | Toshi Kani <toshi.kani@hp.com> | 2015-04-15 00:47:20 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-15 01:49:04 +0200 |
| commit | 0ddab1d2ed664c85c95488eef569786a84aedf37 (patch) | |
| tree | b7f2d24f5ba9e307052833500758e0d7bf10bf53 /lib/ioremap.c | |
| parent | mm: change __get_vm_area_node() to use fls_long() (diff) | |
| download | linux-0ddab1d2ed664c85c95488eef569786a84aedf37.tar.xz linux-0ddab1d2ed664c85c95488eef569786a84aedf37.zip | |
lib/ioremap.c: add huge I/O map capability interfaces
Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when
I/O mappings with pud/pmd are enabled on the kernel.
ioremap_huge_init() calls arch_ioremap_pud_supported() and
arch_ioremap_pmd_supported() to initialize the capabilities at boot-time.
A new kernel option "nohugeiomap" is also added, so that user can disable
the huge I/O map capabilities when necessary.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/ioremap.c')
| -rw-r--r-- | lib/ioremap.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/lib/ioremap.c b/lib/ioremap.c index 0c9216c48762..2008652c9a1f 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -13,6 +13,43 @@ #include <asm/cacheflush.h> #include <asm/pgtable.h> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP +int __read_mostly ioremap_pud_capable; +int __read_mostly ioremap_pmd_capable; +int __read_mostly ioremap_huge_disabled; + +static int __init set_nohugeiomap(char *str) +{ + ioremap_huge_disabled = 1; + return 0; +} +early_param("nohugeiomap", set_nohugeiomap); + +void __init ioremap_huge_init(void) +{ + if (!ioremap_huge_disabled) { + if (arch_ioremap_pud_supported()) + ioremap_pud_capable = 1; + if (arch_ioremap_pmd_supported()) + ioremap_pmd_capable = 1; + } +} + +static inline int ioremap_pud_enabled(void) +{ + return ioremap_pud_capable; +} + +static inline int ioremap_pmd_enabled(void) +{ + return ioremap_pmd_capable; +} + +#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */ +static inline int ioremap_pud_enabled(void) { return 0; } +static inline int ioremap_pmd_enabled(void) { return 0; } +#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ + static int ioremap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { |