generic_64.c 4.27 KB
Newer Older
Adrian Bunk's avatar
Adrian Bunk committed
1
/*
Linus Torvalds's avatar
Linus Torvalds committed
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41
 * generic.c: Generic Sparc mm routines that are not dependent upon
 *            MMU type but are Sparc specific.
 *
 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
 */

#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/pagemap.h>

#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#include <asm/tlbflush.h>

/* Remap IO memory, the same way as remap_pfn_range(), but use
 * the obio memory space.
 *
 * They use a pgprot that sets PAGE_IO and does not check the
 * mem_map table as this is independent of normal memory.
 */
static inline void io_remap_pte_range(struct mm_struct *mm, pte_t * pte,
				      unsigned long address,
				      unsigned long size,
				      unsigned long offset, pgprot_t prot,
				      int space)
{
	unsigned long end;

	/* clear hack bit that was used as a write_combine side-effect flag */
	offset &= ~0x1UL;
	address &= ~PMD_MASK;
	end = address + size;
	if (end > PMD_SIZE)
		end = PMD_SIZE;
	do {
		pte_t entry;
		unsigned long curend = address + PAGE_SIZE;
		
42
		entry = mk_pte_io(offset, prot, space, PAGE_SIZE);
Linus Torvalds's avatar
Linus Torvalds committed
43
		if (!(address & 0xffff)) {
44 45 46 47 48 49
			if (PAGE_SIZE < (4 * 1024 * 1024) &&
			    !(address & 0x3fffff) &&
			    !(offset & 0x3ffffe) &&
			    end >= address + 0x400000) {
				entry = mk_pte_io(offset, prot, space,
						  4 * 1024 * 1024);
Linus Torvalds's avatar
Linus Torvalds committed
50 51
				curend = address + 0x400000;
				offset += 0x400000;
52 53 54 55 56 57
			} else if (PAGE_SIZE < (512 * 1024) &&
				   !(address & 0x7ffff) &&
				   !(offset & 0x7fffe) &&
				   end >= address + 0x80000) {
				entry = mk_pte_io(offset, prot, space,
						  512 * 1024 * 1024);
Linus Torvalds's avatar
Linus Torvalds committed
58 59
				curend = address + 0x80000;
				offset += 0x80000;
60 61 62 63 64
			} else if (PAGE_SIZE < (64 * 1024) &&
				   !(offset & 0xfffe) &&
				   end >= address + 0x10000) {
				entry = mk_pte_io(offset, prot, space,
						  64 * 1024);
Linus Torvalds's avatar
Linus Torvalds committed
65 66 67 68 69 70 71
				curend = address + 0x10000;
				offset += 0x10000;
			} else
				offset += PAGE_SIZE;
		} else
			offset += PAGE_SIZE;

72 73
		if (pte_write(entry))
			entry = pte_mkdirty(entry);
Linus Torvalds's avatar
Linus Torvalds committed
74 75 76 77
		do {
			BUG_ON(!pte_none(*pte));
			set_pte_at(mm, address, pte, entry);
			address += PAGE_SIZE;
78
			pte_val(entry) += PAGE_SIZE;
Linus Torvalds's avatar
Linus Torvalds committed
79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136
			pte++;
		} while (address < curend);
	} while (address < end);
}

static inline int io_remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned long address, unsigned long size,
	unsigned long offset, pgprot_t prot, int space)
{
	unsigned long end;

	address &= ~PGDIR_MASK;
	end = address + size;
	if (end > PGDIR_SIZE)
		end = PGDIR_SIZE;
	offset -= address;
	do {
		pte_t * pte = pte_alloc_map(mm, pmd, address);
		if (!pte)
			return -ENOMEM;
		io_remap_pte_range(mm, pte, address, end - address, address + offset, prot, space);
		pte_unmap(pte);
		address = (address + PMD_SIZE) & PMD_MASK;
		pmd++;
	} while (address < end);
	return 0;
}

static inline int io_remap_pud_range(struct mm_struct *mm, pud_t * pud, unsigned long address, unsigned long size,
	unsigned long offset, pgprot_t prot, int space)
{
	unsigned long end;

	address &= ~PUD_MASK;
	end = address + size;
	if (end > PUD_SIZE)
		end = PUD_SIZE;
	offset -= address;
	do {
		pmd_t *pmd = pmd_alloc(mm, pud, address);
		if (!pud)
			return -ENOMEM;
		io_remap_pmd_range(mm, pmd, address, end - address, address + offset, prot, space);
		address = (address + PUD_SIZE) & PUD_MASK;
		pud++;
	} while (address < end);
	return 0;
}

int io_remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
		unsigned long pfn, unsigned long size, pgprot_t prot)
{
	int error = 0;
	pgd_t * dir;
	unsigned long beg = from;
	unsigned long end = from + size;
	struct mm_struct *mm = vma->vm_mm;
	int space = GET_IOSPACE(pfn);
	unsigned long offset = GET_PFN(pfn) << PAGE_SHIFT;
137 138 139
	unsigned long phys_base;

	phys_base = offset | (((unsigned long) space) << 32UL);
Linus Torvalds's avatar
Linus Torvalds committed
140

141
	/* See comment in mm/memory.c remap_pfn_range */
142 143
	vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
	vma->vm_pgoff = phys_base >> PAGE_SHIFT;
144

Linus Torvalds's avatar
Linus Torvalds committed
145 146 147 148 149
	offset -= from;
	dir = pgd_offset(mm, from);
	flush_cache_range(vma, beg, end);

	while (from < end) {
150
		pud_t *pud = pud_alloc(mm, dir, from);
Linus Torvalds's avatar
Linus Torvalds committed
151 152 153 154 155 156 157 158 159 160
		error = -ENOMEM;
		if (!pud)
			break;
		error = io_remap_pud_range(mm, pud, from, end - from, offset + from, prot, space);
		if (error)
			break;
		from = (from + PGDIR_SIZE) & PGDIR_MASK;
		dir++;
	}

161
	flush_tlb_range(vma, beg, end);
Linus Torvalds's avatar
Linus Torvalds committed
162 163
	return error;
}
164
EXPORT_SYMBOL(io_remap_pfn_range);