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>
This commit is contained in:
Toshi Kani 2015-04-14 15:47:20 -07:00 committed by Linus Torvalds
parent 0f616be120
commit 0ddab1d2ed
5 changed files with 52 additions and 0 deletions

View file

@ -38,6 +38,14 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end,
}
#endif
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
void __init ioremap_huge_init(void);
int arch_ioremap_pud_supported(void);
int arch_ioremap_pmd_supported(void);
#else
static inline void ioremap_huge_init(void) { }
#endif
/*
* Managed iomap interface
*/