Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 283 insertions, 0 deletions

diff --git a/arch/x86_64/mm/ioremap.c b/arch/x86_64/mm/ioremap.c
new file mode 100644
index 000000000000..74ec8554b195
--- /dev/null
+++ b/arch/x86_64/mm/ioremap.c
@@ -0,0 +1,283 @@
+/*
+ * arch/x86_64/mm/ioremap.c
+ *
+ * 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/vmalloc.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <asm/io.h>
+#include <asm/pgalloc.h>
+#include <asm/fixmap.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/proto.h>
+
+#define ISA_START_ADDRESS      0xa0000
+#define ISA_END_ADDRESS                0x100000
+
+static inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
+        unsigned long phys_addr, unsigned long flags)
+{
+        unsigned long end;
+        unsigned long pfn;
+
+        address &= ~PMD_MASK;
+        end = address + size;
+        if (end > PMD_SIZE)
+                end = PMD_SIZE;
+        if (address >= end)
+                BUG();
+        pfn = phys_addr >> PAGE_SHIFT;
+        do {
+                if (!pte_none(*pte)) {
+                        printk("remap_area_pte: page already exists\n");
+                        BUG();
+                }
+                set_pte(pte, pfn_pte(pfn, __pgprot(_PAGE_PRESENT | _PAGE_RW | 
+                                        _PAGE_GLOBAL | _PAGE_DIRTY | _PAGE_ACCESSED | flags)));
+                address += PAGE_SIZE;
+                pfn++;
+                pte++;
+        } while (address && (address < end));
+}
+
+static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
+        unsigned long phys_addr, unsigned long flags)
+{
+        unsigned long end;
+
+        address &= ~PUD_MASK;
+        end = address + size;
+        if (end > PUD_SIZE)
+                end = PUD_SIZE;
+        phys_addr -= address;
+        if (address >= end)
+                BUG();
+        do {
+                pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+                if (!pte)
+                        return -ENOMEM;
+                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
+                address = (address + PMD_SIZE) & PMD_MASK;
+                pmd++;
+        } while (address && (address < end));
+        return 0;
+}
+
+static inline int remap_area_pud(pud_t * pud, unsigned long address, unsigned long size,
+        unsigned long phys_addr, unsigned long flags)
+{
+        unsigned long end;
+
+        address &= ~PGDIR_MASK;
+        end = address + size;
+        if (end > PGDIR_SIZE)
+                end = PGDIR_SIZE;
+        phys_addr -= address;
+        if (address >= end)
+                BUG();
+        do {
+                pmd_t * pmd = pmd_alloc(&init_mm, pud, address);
+                if (!pmd)
+                        return -ENOMEM;
+                remap_area_pmd(pmd, address, end - address, address + phys_addr, flags);
+                address = (address + PUD_SIZE) & PUD_MASK;
+                pud++;
+        } while (address && (address < end));
+        return 0;
+}
+
+static int remap_area_pages(unsigned long address, unsigned long phys_addr,
+                                 unsigned long size, unsigned long flags)
+{
+        int error;
+        pgd_t *pgd;
+        unsigned long end = address + size;
+
+        phys_addr -= address;
+        pgd = pgd_offset_k(address);
+        flush_cache_all();
+        if (address >= end)
+                BUG();
+        spin_lock(&init_mm.page_table_lock);
+        do {
+                pud_t *pud;
+                pud = pud_alloc(&init_mm, pgd, address);
+                error = -ENOMEM;
+                if (!pud)
+                        break;
+                if (remap_area_pud(pud, address, end - address,
+                                         phys_addr + address, flags))
+                        break;
+                error = 0;
+                address = (address + PGDIR_SIZE) & PGDIR_MASK;
+                pgd++;
+        } while (address && (address < end));
+        spin_unlock(&init_mm.page_table_lock);
+        flush_tlb_all();
+        return error;
+}
+
+/*
+ * Fix up the linear direct mapping of the kernel to avoid cache attribute
+ * conflicts.
+ */
+static int
+ioremap_change_attr(unsigned long phys_addr, unsigned long size,
+                                        unsigned long flags)
+{
+        int err = 0;
+        if (flags && phys_addr + size - 1 < (end_pfn_map << PAGE_SHIFT)) {
+                unsigned long npages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
+                unsigned long vaddr = (unsigned long) __va(phys_addr);
+
+                /*
+                 * Must use a address here and not struct page because the phys addr
+                 * can be a in hole between nodes and not have an memmap entry.
+                 */
+                err = change_page_attr_addr(vaddr,npages,__pgprot(__PAGE_KERNEL|flags));
+                if (!err)
+                        global_flush_tlb();
+        }
+        return err;
+}
+
+/*
+ * Generic mapping function
+ */
+
+/*
+ * Remap an arbitrary physical address space into the kernel virtual
+ * address space. Needed when the kernel wants to access high addresses
+ * directly.
+ *
+ * NOTE! We need to allow non-page-aligned mappings too: we will obviously
+ * have to convert them into an offset in a page-aligned mapping, but the
+ * caller shouldn't need to know that small detail.
+ */
+void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
+{
+        void * addr;
+        struct vm_struct * area;
+        unsigned long offset, last_addr;
+
+        /* Don't allow wraparound or zero size */
+        last_addr = phys_addr + size - 1;
+        if (!size || last_addr < phys_addr)
+                return NULL;
+
+        /*
+         * Don't remap the low PCI/ISA area, it's always mapped..
+         */
+        if (phys_addr >= ISA_START_ADDRESS && last_addr < ISA_END_ADDRESS)
+                return (__force void __iomem *)phys_to_virt(phys_addr);
+
+#ifndef CONFIG_DISCONTIGMEM
+        /*
+         * Don't allow anybody to remap normal RAM that we're using..
+         */
+        if (last_addr < virt_to_phys(high_memory)) {
+                char *t_addr, *t_end;
+                struct page *page;
+
+                t_addr = __va(phys_addr);
+                t_end = t_addr + (size - 1);
+           
+                for(page = virt_to_page(t_addr); page <= virt_to_page(t_end); page++)
+                        if(!PageReserved(page))
+                                return NULL;
+        }
+#endif
+
+        /*
+         * Mappings have to be page-aligned
+         */
+        offset = phys_addr & ~PAGE_MASK;
+        phys_addr &= PAGE_MASK;
+        size = PAGE_ALIGN(last_addr+1) - phys_addr;
+
+        /*
+         * Ok, go for it..
+         */
+        area = get_vm_area(size, VM_IOREMAP | (flags << 20));
+        if (!area)
+                return NULL;
+        area->phys_addr = phys_addr;
+        addr = area->addr;
+        if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
+                remove_vm_area((void *)(PAGE_MASK & (unsigned long) addr));
+                return NULL;
+        }
+        if (ioremap_change_attr(phys_addr, size, flags) < 0) {
+                area->flags &= 0xffffff;
+                vunmap(addr);
+                return NULL;
+        }
+        return (__force void __iomem *) (offset + (char *)addr);
+}
+
+/**
+ * ioremap_nocache     -   map bus memory into CPU space
+ * @offset:    bus address of the memory
+ * @size:      size of the resource to map
+ *
+ * ioremap_nocache performs a platform specific sequence of operations to
+ * make bus memory CPU accessible via the readb/readw/readl/writeb/
+ * writew/writel functions and the other mmio helpers. The returned
+ * address is not guaranteed to be usable directly as a virtual
+ * address. 
+ *
+ * This version of ioremap ensures that the memory is marked uncachable
+ * on the CPU as well as honouring existing caching rules from things like
+ * the PCI bus. Note that there are other caches and buffers on many 
+ * busses. In particular driver authors should read up on PCI writes
+ *
+ * It's useful if some control registers are in such an area and
+ * write combining or read caching is not desirable:
+ * 
+ * Must be freed with iounmap.
+ */
+
+void __iomem *ioremap_nocache (unsigned long phys_addr, unsigned long size)
+{
+        return __ioremap(phys_addr, size, _PAGE_PCD);
+}
+
+void iounmap(volatile void __iomem *addr)
+{
+        struct vm_struct *p, **pprev;
+
+        if (addr <= high_memory) 
+                return; 
+        if (addr >= phys_to_virt(ISA_START_ADDRESS) &&
+                addr < phys_to_virt(ISA_END_ADDRESS))
+                return;
+
+        write_lock(&vmlist_lock);
+        for (p = vmlist, pprev = &vmlist; p != NULL; pprev = &p->next, p = *pprev)
+                if (p->addr == (void *)(PAGE_MASK & (unsigned long)addr))
+                        break;
+        if (!p) { 
+                printk("__iounmap: bad address %p\n", addr);
+                goto out_unlock;
+        }
+        *pprev = p->next;
+        unmap_vm_area(p);
+        if ((p->flags >> 20) &&
+                p->phys_addr + p->size - 1 < virt_to_phys(high_memory)) {
+                /* p->size includes the guard page, but cpa doesn't like that */
+                change_page_attr(virt_to_page(__va(p->phys_addr)),
+                                 p->size >> PAGE_SHIFT,
+                                 PAGE_KERNEL);
+                global_flush_tlb();
+        } 
+out_unlock:
+        write_unlock(&vmlist_lock);
+        kfree(p); 
+}