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Commit e61ce6ad authored by Toshi Kani's avatar Toshi Kani Committed by Linus Torvalds
Browse files

mm: change ioremap to set up huge I/O mappings 



ioremap_pud_range() and ioremap_pmd_range() are changed to create huge I/O
mappings when their capability is enabled, and a request meets required
conditions -- both virtual & physical addresses are aligned by their huge
page size, and a requested range fufills their huge page size.  When
pud_set_huge() or pmd_set_huge() returns zero, i.e.  no-operation is
performed, the code simply falls back to the next level.

The changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined on
the architecture.

Signed-off-by: default avatarToshi 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 0ddab1d2

include/asm-generic/pgtable.h

+15 −0
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 


#include <linux/mm_types.h>

#include <linux/bug.h>

#include <linux/errno.h>



#if 4 - defined(__PAGETABLE_PUD_FOLDED) - defined(__PAGETABLE_PMD_FOLDED) != \

	CONFIG_PGTABLE_LEVELS
@@ -696,6 +697,20 @@ static inline int pmd_protnone(pmd_t pmd) 


#endif /* CONFIG_MMU */



#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP

int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot);

int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot);

#else	/* !CONFIG_HAVE_ARCH_HUGE_VMAP */

static inline int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)

{

	return 0;

}

static inline int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)

{

	return 0;

}

#endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */



#endif /* !__ASSEMBLY__ */



#ifndef io_remap_pfn_range

lib/ioremap.c

+16 −0
Original line number Diff line number Diff line
@@ -80,6 +80,14 @@ static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr, 
		return -ENOMEM;

	do {

		next = pmd_addr_end(addr, end);



		if (ioremap_pmd_enabled() &&

		    ((next - addr) == PMD_SIZE) &&

		    IS_ALIGNED(phys_addr + addr, PMD_SIZE)) {

			if (pmd_set_huge(pmd, phys_addr + addr, prot))

				continue;

		}



		if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))

			return -ENOMEM;

	} while (pmd++, addr = next, addr != end);
@@ -98,6 +106,14 @@ static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr, 
		return -ENOMEM;

	do {

		next = pud_addr_end(addr, end);



		if (ioremap_pud_enabled() &&

		    ((next - addr) == PUD_SIZE) &&

		    IS_ALIGNED(phys_addr + addr, PUD_SIZE)) {

			if (pud_set_huge(pud, phys_addr + addr, prot))

				continue;

		}



		if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))

			return -ENOMEM;

	} while (pud++, addr = next, addr != end);