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author | Haavard Skinnemoen <hskinnemoen@atmel.com> | 2006-09-30 23:29:12 -0700 |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-01 00:39:31 -0700 |
commit | 74588d8ba34ff1bda027cfa737972af01ab00c8b (patch) | |
tree | 5e889e96d29c96e9c54ff72933de0612c61e9835 /lib | |
parent | bc03613decef0cc4d2f3a24f19fa5a868745715f (diff) | |
download | linux-stable-74588d8ba34ff1bda027cfa737972af01ab00c8b.tar.gz linux-stable-74588d8ba34ff1bda027cfa737972af01ab00c8b.tar.bz2 linux-stable-74588d8ba34ff1bda027cfa737972af01ab00c8b.zip |
[PATCH] Generic ioremap_page_range: implementation
This patch adds a generic implementation of ioremap_page_range() in
lib/ioremap.c based on the i386 implementation. It differs from the
i386 version in the following ways:
* The PTE flags are passed as a pgprot_t argument and must be
determined up front by the arch-specific code. No additional
PTE flags are added.
* Uses set_pte_at() instead of set_pte()
[bunk@stusta.de: warning fix]
]dhowells@redhat.com: nommu build fix]
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Andi Kleen <ak@suse.de>
Cc: <linux-m32r@ml.linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@parisc-linux.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Makefile | 1 | ||||
-rw-r--r-- | lib/ioremap.c | 94 |
2 files changed, 95 insertions, 0 deletions
diff --git a/lib/Makefile b/lib/Makefile index 402762fead70..ddf3e676e1f4 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -7,6 +7,7 @@ lib-y := errno.o ctype.o string.o vsprintf.o cmdline.o \ idr.o div64.o int_sqrt.o bitmap.o extable.o prio_tree.o \ sha1.o +lib-$(CONFIG_MMU) += ioremap.o lib-$(CONFIG_SMP) += cpumask.o lib-y += kobject.o kref.o kobject_uevent.o klist.o diff --git a/lib/ioremap.c b/lib/ioremap.c new file mode 100644 index 000000000000..29c810ec9813 --- /dev/null +++ b/lib/ioremap.c @@ -0,0 +1,94 @@ +/* + * Re-map IO memory to kernel address space so that we can access it. + * This is needed for high PCI addresses that aren't mapped in the + * 640k-1MB IO memory area on PC's + * + * (C) Copyright 1995 1996 Linus Torvalds + */ +#include <linux/io.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> + +#include <asm/cacheflush.h> +#include <asm/pgtable.h> + +static int ioremap_pte_range(pmd_t *pmd, unsigned long addr, + unsigned long end, unsigned long phys_addr, pgprot_t prot) +{ + pte_t *pte; + unsigned long pfn; + + pfn = phys_addr >> PAGE_SHIFT; + pte = pte_alloc_kernel(pmd, addr); + if (!pte) + return -ENOMEM; + do { + BUG_ON(!pte_none(*pte)); + set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot)); + pfn++; + } while (pte++, addr += PAGE_SIZE, addr != end); + return 0; +} + +static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr, + unsigned long end, unsigned long phys_addr, pgprot_t prot) +{ + pmd_t *pmd; + unsigned long next; + + phys_addr -= addr; + pmd = pmd_alloc(&init_mm, pud, addr); + if (!pmd) + return -ENOMEM; + do { + next = pmd_addr_end(addr, end); + if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot)) + return -ENOMEM; + } while (pmd++, addr = next, addr != end); + return 0; +} + +static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr, + unsigned long end, unsigned long phys_addr, pgprot_t prot) +{ + pud_t *pud; + unsigned long next; + + phys_addr -= addr; + pud = pud_alloc(&init_mm, pgd, addr); + if (!pud) + return -ENOMEM; + do { + next = pud_addr_end(addr, end); + if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot)) + return -ENOMEM; + } while (pud++, addr = next, addr != end); + return 0; +} + +int ioremap_page_range(unsigned long addr, + unsigned long end, unsigned long phys_addr, pgprot_t prot) +{ + pgd_t *pgd; + unsigned long start; + unsigned long next; + int err; + + BUG_ON(addr >= end); + + flush_cache_all(); + + start = addr; + phys_addr -= addr; + pgd = pgd_offset_k(addr); + do { + next = pgd_addr_end(addr, end); + err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot); + if (err) + break; + } while (pgd++, addr = next, addr != end); + + flush_tlb_all(); + + return err; +} |