File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/microblaze/mm/Makefile b/arch/microblaze/mm/Makefile
new file mode 100644
index 0000000..7313bd8
--- /dev/null
+++ b/arch/microblaze/mm/Makefile
@@ -0,0 +1,8 @@
+#
+# Makefile
+#
+
+obj-y := consistent.o init.o
+
+obj-$(CONFIG_MMU) += pgtable.o mmu_context.o fault.o
+obj-$(CONFIG_HIGHMEM) += highmem.o
diff --git a/arch/microblaze/mm/consistent.c b/arch/microblaze/mm/consistent.c
new file mode 100644
index 0000000..b06c3a7
--- /dev/null
+++ b/arch/microblaze/mm/consistent.c
@@ -0,0 +1,266 @@
+/*
+ * Microblaze support for cache consistent memory.
+ * Copyright (C) 2010 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2010 PetaLogix
+ * Copyright (C) 2005 John Williams <jwilliams@itee.uq.edu.au>
+ *
+ * Based on PowerPC version derived from arch/arm/mm/consistent.c
+ * Copyright (C) 2001 Dan Malek (dmalek@jlc.net)
+ * Copyright (C) 2000 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/export.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/stddef.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/gfp.h>
+
+#include <asm/pgalloc.h>
+#include <linux/io.h>
+#include <linux/hardirq.h>
+#include <linux/mmu_context.h>
+#include <asm/mmu.h>
+#include <linux/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/cpuinfo.h>
+#include <asm/tlbflush.h>
+
+#ifndef CONFIG_MMU
+/* I have to use dcache values because I can't relate on ram size */
+# define UNCACHED_SHADOW_MASK (cpuinfo.dcache_high - cpuinfo.dcache_base + 1)
+#endif
+
+/*
+ * Consistent memory allocators. Used for DMA devices that want to
+ * share uncached memory with the processor core.
+ * My crufty no-MMU approach is simple. In the HW platform we can optionally
+ * mirror the DDR up above the processor cacheable region. So, memory accessed
+ * in this mirror region will not be cached. It's alloced from the same
+ * pool as normal memory, but the handle we return is shifted up into the
+ * uncached region. This will no doubt cause big problems if memory allocated
+ * here is not also freed properly. -- JW
+ */
+void *consistent_alloc(gfp_t gfp, size_t size, dma_addr_t *dma_handle)
+{
+ unsigned long order, vaddr;
+ void *ret;
+ unsigned int i, err = 0;
+ struct page *page, *end;
+
+#ifdef CONFIG_MMU
+ phys_addr_t pa;
+ struct vm_struct *area;
+ unsigned long va;
+#endif
+
+ if (in_interrupt())
+ BUG();
+
+ /* Only allocate page size areas. */
+ size = PAGE_ALIGN(size);
+ order = get_order(size);
+
+ vaddr = __get_free_pages(gfp, order);
+ if (!vaddr)
+ return NULL;
+
+ /*
+ * we need to ensure that there are no cachelines in use,
+ * or worse dirty in this area.
+ */
+ flush_dcache_range(virt_to_phys((void *)vaddr),
+ virt_to_phys((void *)vaddr) + size);
+
+#ifndef CONFIG_MMU
+ ret = (void *)vaddr;
+ /*
+ * Here's the magic! Note if the uncached shadow is not implemented,
+ * it's up to the calling code to also test that condition and make
+ * other arranegments, such as manually flushing the cache and so on.
+ */
+# ifdef CONFIG_XILINX_UNCACHED_SHADOW
+ ret = (void *)((unsigned) ret | UNCACHED_SHADOW_MASK);
+# endif
+ if ((unsigned int)ret > cpuinfo.dcache_base &&
+ (unsigned int)ret < cpuinfo.dcache_high)
+ pr_warn("ERROR: Your cache coherent area is CACHED!!!\n");
+
+ /* dma_handle is same as physical (shadowed) address */
+ *dma_handle = (dma_addr_t)ret;
+#else
+ /* Allocate some common virtual space to map the new pages. */
+ area = get_vm_area(size, VM_ALLOC);
+ if (!area) {
+ free_pages(vaddr, order);
+ return NULL;
+ }
+ va = (unsigned long) area->addr;
+ ret = (void *)va;
+
+ /* This gives us the real physical address of the first page. */
+ *dma_handle = pa = __virt_to_phys(vaddr);
+#endif
+
+ /*
+ * free wasted pages. We skip the first page since we know
+ * that it will have count = 1 and won't require freeing.
+ * We also mark the pages in use as reserved so that
+ * remap_page_range works.
+ */
+ page = virt_to_page(vaddr);
+ end = page + (1 << order);
+
+ split_page(page, order);
+
+ for (i = 0; i < size && err == 0; i += PAGE_SIZE) {
+#ifdef CONFIG_MMU
+ /* MS: This is the whole magic - use cache inhibit pages */
+ err = map_page(va + i, pa + i, _PAGE_KERNEL | _PAGE_NO_CACHE);
+#endif
+
+ SetPageReserved(page);
+ page++;
+ }
+
+ /* Free the otherwise unused pages. */
+ while (page < end) {
+ __free_page(page);
+ page++;
+ }
+
+ if (err) {
+ free_pages(vaddr, order);
+ return NULL;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(consistent_alloc);
+
+#ifdef CONFIG_MMU
+static pte_t *consistent_virt_to_pte(void *vaddr)
+{
+ unsigned long addr = (unsigned long)vaddr;
+
+ return pte_offset_kernel(pmd_offset(pgd_offset_k(addr), addr), addr);
+}
+
+unsigned long consistent_virt_to_pfn(void *vaddr)
+{
+ pte_t *ptep = consistent_virt_to_pte(vaddr);
+
+ if (pte_none(*ptep) || !pte_present(*ptep))
+ return 0;
+
+ return pte_pfn(*ptep);
+}
+#endif
+
+/*
+ * free page(s) as defined by the above mapping.
+ */
+void consistent_free(size_t size, void *vaddr)
+{
+ struct page *page;
+
+ if (in_interrupt())
+ BUG();
+
+ size = PAGE_ALIGN(size);
+
+#ifndef CONFIG_MMU
+ /* Clear SHADOW_MASK bit in address, and free as per usual */
+# ifdef CONFIG_XILINX_UNCACHED_SHADOW
+ vaddr = (void *)((unsigned)vaddr & ~UNCACHED_SHADOW_MASK);
+# endif
+ page = virt_to_page(vaddr);
+
+ do {
+ __free_reserved_page(page);
+ page++;
+ } while (size -= PAGE_SIZE);
+#else
+ do {
+ pte_t *ptep = consistent_virt_to_pte(vaddr);
+ unsigned long pfn;
+
+ if (!pte_none(*ptep) && pte_present(*ptep)) {
+ pfn = pte_pfn(*ptep);
+ pte_clear(&init_mm, (unsigned int)vaddr, ptep);
+ if (pfn_valid(pfn)) {
+ page = pfn_to_page(pfn);
+ __free_reserved_page(page);
+ }
+ }
+ vaddr += PAGE_SIZE;
+ } while (size -= PAGE_SIZE);
+
+ /* flush tlb */
+ flush_tlb_all();
+#endif
+}
+EXPORT_SYMBOL(consistent_free);
+
+/*
+ * make an area consistent.
+ */
+void consistent_sync(void *vaddr, size_t size, int direction)
+{
+ unsigned long start;
+ unsigned long end;
+
+ start = (unsigned long)vaddr;
+
+ /* Convert start address back down to unshadowed memory region */
+#ifdef CONFIG_XILINX_UNCACHED_SHADOW
+ start &= ~UNCACHED_SHADOW_MASK;
+#endif
+ end = start + size;
+
+ switch (direction) {
+ case PCI_DMA_NONE:
+ BUG();
+ case PCI_DMA_FROMDEVICE: /* invalidate only */
+ invalidate_dcache_range(start, end);
+ break;
+ case PCI_DMA_TODEVICE: /* writeback only */
+ flush_dcache_range(start, end);
+ break;
+ case PCI_DMA_BIDIRECTIONAL: /* writeback and invalidate */
+ flush_dcache_range(start, end);
+ break;
+ }
+}
+EXPORT_SYMBOL(consistent_sync);
+
+/*
+ * consistent_sync_page makes memory consistent. identical
+ * to consistent_sync, but takes a struct page instead of a
+ * virtual address
+ */
+void consistent_sync_page(struct page *page, unsigned long offset,
+ size_t size, int direction)
+{
+ unsigned long start = (unsigned long)page_address(page) + offset;
+ consistent_sync((void *)start, size, direction);
+}
+EXPORT_SYMBOL(consistent_sync_page);
diff --git a/arch/microblaze/mm/fault.c b/arch/microblaze/mm/fault.c
new file mode 100644
index 0000000..177dfc0
--- /dev/null
+++ b/arch/microblaze/mm/fault.c
@@ -0,0 +1,306 @@
+/*
+ * arch/microblaze/mm/fault.c
+ *
+ * Copyright (C) 2007 Xilinx, Inc. All rights reserved.
+ *
+ * Derived from "arch/ppc/mm/fault.c"
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Derived from "arch/i386/mm/fault.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * Modified by Cort Dougan and Paul Mackerras.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <linux/mmu_context.h>
+#include <linux/uaccess.h>
+#include <asm/exceptions.h>
+
+static unsigned long pte_misses; /* updated by do_page_fault() */
+static unsigned long pte_errors; /* updated by do_page_fault() */
+
+/*
+ * Check whether the instruction at regs->pc is a store using
+ * an update addressing form which will update r1.
+ */
+static int store_updates_sp(struct pt_regs *regs)
+{
+ unsigned int inst;
+
+ if (get_user(inst, (unsigned int __user *)regs->pc))
+ return 0;
+ /* check for 1 in the rD field */
+ if (((inst >> 21) & 0x1f) != 1)
+ return 0;
+ /* check for store opcodes */
+ if ((inst & 0xd0000000) == 0xd0000000)
+ return 1;
+ return 0;
+}
+
+
+/*
+ * bad_page_fault is called when we have a bad access from the kernel.
+ * It is called from do_page_fault above and from some of the procedures
+ * in traps.c.
+ */
+void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
+{
+ const struct exception_table_entry *fixup;
+/* MS: no context */
+ /* Are we prepared to handle this fault? */
+ fixup = search_exception_tables(regs->pc);
+ if (fixup) {
+ regs->pc = fixup->fixup;
+ return;
+ }
+
+ /* kernel has accessed a bad area */
+ die("kernel access of bad area", regs, sig);
+}
+
+/*
+ * The error_code parameter is ESR for a data fault,
+ * 0 for an instruction fault.
+ */
+void do_page_fault(struct pt_regs *regs, unsigned long address,
+ unsigned long error_code)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = current->mm;
+ siginfo_t info;
+ int code = SEGV_MAPERR;
+ int is_write = error_code & ESR_S;
+ int fault;
+ unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+
+ regs->ear = address;
+ regs->esr = error_code;
+
+ /* On a kernel SLB miss we can only check for a valid exception entry */
+ if (unlikely(kernel_mode(regs) && (address >= TASK_SIZE))) {
+ pr_warn("kernel task_size exceed");
+ _exception(SIGSEGV, regs, code, address);
+ }
+
+ /* for instr TLB miss and instr storage exception ESR_S is undefined */
+ if ((error_code & 0x13) == 0x13 || (error_code & 0x11) == 0x11)
+ is_write = 0;
+
+ if (unlikely(faulthandler_disabled() || !mm)) {
+ if (kernel_mode(regs))
+ goto bad_area_nosemaphore;
+
+ /* faulthandler_disabled() in user mode is really bad,
+ as is current->mm == NULL. */
+ pr_emerg("Page fault in user mode with faulthandler_disabled(), mm = %p\n",
+ mm);
+ pr_emerg("r15 = %lx MSR = %lx\n",
+ regs->r15, regs->msr);
+ die("Weird page fault", regs, SIGSEGV);
+ }
+
+ if (user_mode(regs))
+ flags |= FAULT_FLAG_USER;
+
+ /* When running in the kernel we expect faults to occur only to
+ * addresses in user space. All other faults represent errors in the
+ * kernel and should generate an OOPS. Unfortunately, in the case of an
+ * erroneous fault occurring in a code path which already holds mmap_sem
+ * we will deadlock attempting to validate the fault against the
+ * address space. Luckily the kernel only validly references user
+ * space from well defined areas of code, which are listed in the
+ * exceptions table.
+ *
+ * As the vast majority of faults will be valid we will only perform
+ * the source reference check when there is a possibility of a deadlock.
+ * Attempt to lock the address space, if we cannot we then validate the
+ * source. If this is invalid we can skip the address space check,
+ * thus avoiding the deadlock.
+ */
+ if (unlikely(!down_read_trylock(&mm->mmap_sem))) {
+ if (kernel_mode(regs) && !search_exception_tables(regs->pc))
+ goto bad_area_nosemaphore;
+
+retry:
+ down_read(&mm->mmap_sem);
+ }
+
+ vma = find_vma(mm, address);
+ if (unlikely(!vma))
+ goto bad_area;
+
+ if (vma->vm_start <= address)
+ goto good_area;
+
+ if (unlikely(!(vma->vm_flags & VM_GROWSDOWN)))
+ goto bad_area;
+
+ if (unlikely(!is_write))
+ goto bad_area;
+
+ /*
+ * N.B. The ABI allows programs to access up to
+ * a few hundred bytes below the stack pointer (TBD).
+ * The kernel signal delivery code writes up to about 1.5kB
+ * below the stack pointer (r1) before decrementing it.
+ * The exec code can write slightly over 640kB to the stack
+ * before setting the user r1. Thus we allow the stack to
+ * expand to 1MB without further checks.
+ */
+ if (unlikely(address + 0x100000 < vma->vm_end)) {
+
+ /* get user regs even if this fault is in kernel mode */
+ struct pt_regs *uregs = current->thread.regs;
+ if (uregs == NULL)
+ goto bad_area;
+
+ /*
+ * A user-mode access to an address a long way below
+ * the stack pointer is only valid if the instruction
+ * is one which would update the stack pointer to the
+ * address accessed if the instruction completed,
+ * i.e. either stwu rs,n(r1) or stwux rs,r1,rb
+ * (or the byte, halfword, float or double forms).
+ *
+ * If we don't check this then any write to the area
+ * between the last mapped region and the stack will
+ * expand the stack rather than segfaulting.
+ */
+ if (address + 2048 < uregs->r1
+ && (kernel_mode(regs) || !store_updates_sp(regs)))
+ goto bad_area;
+ }
+ if (expand_stack(vma, address))
+ goto bad_area;
+
+good_area:
+ code = SEGV_ACCERR;
+
+ /* a write */
+ if (unlikely(is_write)) {
+ if (unlikely(!(vma->vm_flags & VM_WRITE)))
+ goto bad_area;
+ flags |= FAULT_FLAG_WRITE;
+ /* a read */
+ } else {
+ /* protection fault */
+ if (unlikely(error_code & 0x08000000))
+ goto bad_area;
+ if (unlikely(!(vma->vm_flags & (VM_READ | VM_EXEC))))
+ goto bad_area;
+ }
+
+ /*
+ * If for any reason at all we couldn't handle the fault,
+ * make sure we exit gracefully rather than endlessly redo
+ * the fault.
+ */
+ fault = handle_mm_fault(mm, vma, address, flags);
+
+ if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
+ return;
+
+ if (unlikely(fault & VM_FAULT_ERROR)) {
+ if (fault & VM_FAULT_OOM)
+ goto out_of_memory;
+ else if (fault & VM_FAULT_SIGSEGV)
+ goto bad_area;
+ else if (fault & VM_FAULT_SIGBUS)
+ goto do_sigbus;
+ BUG();
+ }
+
+ if (flags & FAULT_FLAG_ALLOW_RETRY) {
+ if (unlikely(fault & VM_FAULT_MAJOR))
+ current->maj_flt++;
+ else
+ current->min_flt++;
+ if (fault & VM_FAULT_RETRY) {
+ flags &= ~FAULT_FLAG_ALLOW_RETRY;
+ flags |= FAULT_FLAG_TRIED;
+
+ /*
+ * No need to up_read(&mm->mmap_sem) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
+
+ goto retry;
+ }
+ }
+
+ up_read(&mm->mmap_sem);
+
+ /*
+ * keep track of tlb+htab misses that are good addrs but
+ * just need pte's created via handle_mm_fault()
+ * -- Cort
+ */
+ pte_misses++;
+ return;
+
+bad_area:
+ up_read(&mm->mmap_sem);
+
+bad_area_nosemaphore:
+ pte_errors++;
+
+ /* User mode accesses cause a SIGSEGV */
+ if (user_mode(regs)) {
+ _exception(SIGSEGV, regs, code, address);
+/* info.si_signo = SIGSEGV;
+ info.si_errno = 0;
+ info.si_code = code;
+ info.si_addr = (void *) address;
+ force_sig_info(SIGSEGV, &info, current);*/
+ return;
+ }
+
+ bad_page_fault(regs, address, SIGSEGV);
+ return;
+
+/*
+ * We ran out of memory, or some other thing happened to us that made
+ * us unable to handle the page fault gracefully.
+ */
+out_of_memory:
+ up_read(&mm->mmap_sem);
+ if (!user_mode(regs))
+ bad_page_fault(regs, address, SIGKILL);
+ else
+ pagefault_out_of_memory();
+ return;
+
+do_sigbus:
+ up_read(&mm->mmap_sem);
+ if (user_mode(regs)) {
+ info.si_signo = SIGBUS;
+ info.si_errno = 0;
+ info.si_code = BUS_ADRERR;
+ info.si_addr = (void __user *)address;
+ force_sig_info(SIGBUS, &info, current);
+ return;
+ }
+ bad_page_fault(regs, address, SIGBUS);
+}
diff --git a/arch/microblaze/mm/highmem.c b/arch/microblaze/mm/highmem.c
new file mode 100644
index 0000000..2fcc5a5
--- /dev/null
+++ b/arch/microblaze/mm/highmem.c
@@ -0,0 +1,90 @@
+/*
+ * highmem.c: virtual kernel memory mappings for high memory
+ *
+ * PowerPC version, stolen from the i386 version.
+ *
+ * Used in CONFIG_HIGHMEM systems for memory pages which
+ * are not addressable by direct kernel virtual addresses.
+ *
+ * Copyright (C) 1999 Gerhard Wichert, Siemens AG
+ * Gerhard.Wichert@pdb.siemens.de
+ *
+ *
+ * Redesigned the x86 32-bit VM architecture to deal with
+ * up to 16 Terrabyte physical memory. With current x86 CPUs
+ * we now support up to 64 Gigabytes physical RAM.
+ *
+ * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
+ *
+ * Reworked for PowerPC by various contributors. Moved from
+ * highmem.h by Benjamin Herrenschmidt (c) 2009 IBM Corp.
+ */
+
+#include <linux/export.h>
+#include <linux/highmem.h>
+
+/*
+ * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
+ * gives a more generic (and caching) interface. But kmap_atomic can
+ * be used in IRQ contexts, so in some (very limited) cases we need
+ * it.
+ */
+#include <asm/tlbflush.h>
+
+void *kmap_atomic_prot(struct page *page, pgprot_t prot)
+{
+
+ unsigned long vaddr;
+ int idx, type;
+
+ preempt_disable();
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+
+
+ type = kmap_atomic_idx_push();
+ idx = type + KM_TYPE_NR*smp_processor_id();
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+ BUG_ON(!pte_none(*(kmap_pte-idx)));
+#endif
+ set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot));
+ local_flush_tlb_page(NULL, vaddr);
+
+ return (void *) vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic_prot);
+
+void __kunmap_atomic(void *kvaddr)
+{
+ unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
+ int type;
+
+ if (vaddr < __fix_to_virt(FIX_KMAP_END)) {
+ pagefault_enable();
+ preempt_enable();
+ return;
+ }
+
+ type = kmap_atomic_idx();
+#ifdef CONFIG_DEBUG_HIGHMEM
+ {
+ unsigned int idx;
+
+ idx = type + KM_TYPE_NR * smp_processor_id();
+ BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+
+ /*
+ * force other mappings to Oops if they'll try to access
+ * this pte without first remap it
+ */
+ pte_clear(&init_mm, vaddr, kmap_pte-idx);
+ local_flush_tlb_page(NULL, vaddr);
+ }
+#endif
+ kmap_atomic_idx_pop();
+ pagefault_enable();
+ preempt_enable();
+}
+EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c
new file mode 100644
index 0000000..77bc7c7
--- /dev/null
+++ b/arch/microblaze/mm/init.c
@@ -0,0 +1,437 @@
+/*
+ * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2006 Atmark Techno, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/bootmem.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/memblock.h>
+#include <linux/mm.h> /* mem_init */
+#include <linux/initrd.h>
+#include <linux/pagemap.h>
+#include <linux/pfn.h>
+#include <linux/slab.h>
+#include <linux/swap.h>
+#include <linux/export.h>
+
+#include <asm/page.h>
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+#include <asm/sections.h>
+#include <asm/tlb.h>
+#include <asm/fixmap.h>
+
+/* Use for MMU and noMMU because of PCI generic code */
+int mem_init_done;
+
+#ifndef CONFIG_MMU
+unsigned int __page_offset;
+EXPORT_SYMBOL(__page_offset);
+
+#else
+static int init_bootmem_done;
+#endif /* CONFIG_MMU */
+
+char *klimit = _end;
+
+/*
+ * Initialize the bootmem system and give it all the memory we
+ * have available.
+ */
+unsigned long memory_start;
+EXPORT_SYMBOL(memory_start);
+unsigned long memory_size;
+EXPORT_SYMBOL(memory_size);
+unsigned long lowmem_size;
+
+#ifdef CONFIG_HIGHMEM
+pte_t *kmap_pte;
+EXPORT_SYMBOL(kmap_pte);
+pgprot_t kmap_prot;
+EXPORT_SYMBOL(kmap_prot);
+
+static inline pte_t *virt_to_kpte(unsigned long vaddr)
+{
+ return pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr),
+ vaddr), vaddr);
+}
+
+static void __init highmem_init(void)
+{
+ pr_debug("%x\n", (u32)PKMAP_BASE);
+ map_page(PKMAP_BASE, 0, 0); /* XXX gross */
+ pkmap_page_table = virt_to_kpte(PKMAP_BASE);
+
+ kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
+ kmap_prot = PAGE_KERNEL;
+}
+
+static void highmem_setup(void)
+{
+ unsigned long pfn;
+
+ for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) {
+ struct page *page = pfn_to_page(pfn);
+
+ /* FIXME not sure about */
+ if (!memblock_is_reserved(pfn << PAGE_SHIFT))
+ free_highmem_page(page);
+ }
+}
+#endif /* CONFIG_HIGHMEM */
+
+/*
+ * paging_init() sets up the page tables - in fact we've already done this.
+ */
+static void __init paging_init(void)
+{
+ unsigned long zones_size[MAX_NR_ZONES];
+#ifdef CONFIG_MMU
+ int idx;
+
+ /* Setup fixmaps */
+ for (idx = 0; idx < __end_of_fixed_addresses; idx++)
+ clear_fixmap(idx);
+#endif
+
+ /* Clean every zones */
+ memset(zones_size, 0, sizeof(zones_size));
+
+#ifdef CONFIG_HIGHMEM
+ highmem_init();
+
+ zones_size[ZONE_DMA] = max_low_pfn;
+ zones_size[ZONE_HIGHMEM] = max_pfn;
+#else
+ zones_size[ZONE_DMA] = max_pfn;
+#endif
+
+ /* We don't have holes in memory map */
+ free_area_init_nodes(zones_size);
+}
+
+void __init setup_memory(void)
+{
+ unsigned long map_size;
+ struct memblock_region *reg;
+
+#ifndef CONFIG_MMU
+ u32 kernel_align_start, kernel_align_size;
+
+ /* Find main memory where is the kernel */
+ for_each_memblock(memory, reg) {
+ memory_start = (u32)reg->base;
+ lowmem_size = reg->size;
+ if ((memory_start <= (u32)_text) &&
+ ((u32)_text <= (memory_start + lowmem_size - 1))) {
+ memory_size = lowmem_size;
+ PAGE_OFFSET = memory_start;
+ pr_info("%s: Main mem: 0x%x, size 0x%08x\n",
+ __func__, (u32) memory_start,
+ (u32) memory_size);
+ break;
+ }
+ }
+
+ if (!memory_start || !memory_size) {
+ panic("%s: Missing memory setting 0x%08x, size=0x%08x\n",
+ __func__, (u32) memory_start, (u32) memory_size);
+ }
+
+ /* reservation of region where is the kernel */
+ kernel_align_start = PAGE_DOWN((u32)_text);
+ /* ALIGN can be remove because _end in vmlinux.lds.S is align */
+ kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
+ pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n",
+ __func__, kernel_align_start, kernel_align_start
+ + kernel_align_size, kernel_align_size);
+ memblock_reserve(kernel_align_start, kernel_align_size);
+#endif
+ /*
+ * Kernel:
+ * start: base phys address of kernel - page align
+ * end: base phys address of kernel - page align
+ *
+ * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
+ * max_low_pfn
+ * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
+ */
+
+ /* memory start is from the kernel end (aligned) to higher addr */
+ min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
+ /* RAM is assumed contiguous */
+ max_mapnr = memory_size >> PAGE_SHIFT;
+ max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT;
+ max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT;
+
+ pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr);
+ pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
+ pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
+ pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn);
+
+ /*
+ * Find an area to use for the bootmem bitmap.
+ * We look for the first area which is at least
+ * 128kB in length (128kB is enough for a bitmap
+ * for 4GB of memory, using 4kB pages), plus 1 page
+ * (in case the address isn't page-aligned).
+ */
+ map_size = init_bootmem_node(NODE_DATA(0),
+ PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn);
+ memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size);
+
+ /* Add active regions with valid PFNs */
+ for_each_memblock(memory, reg) {
+ unsigned long start_pfn, end_pfn;
+
+ start_pfn = memblock_region_memory_base_pfn(reg);
+ end_pfn = memblock_region_memory_end_pfn(reg);
+ memblock_set_node(start_pfn << PAGE_SHIFT,
+ (end_pfn - start_pfn) << PAGE_SHIFT,
+ &memblock.memory, 0);
+ }
+
+ /* free bootmem is whole main memory */
+ free_bootmem_with_active_regions(0, max_low_pfn);
+
+ /* reserve allocate blocks */
+ for_each_memblock(reserved, reg) {
+ unsigned long top = reg->base + reg->size - 1;
+
+ pr_debug("reserved - 0x%08x-0x%08x, %lx, %lx\n",
+ (u32) reg->base, (u32) reg->size, top,
+ memory_start + lowmem_size - 1);
+
+ if (top <= (memory_start + lowmem_size - 1)) {
+ reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
+ } else if (reg->base < (memory_start + lowmem_size - 1)) {
+ unsigned long trunc_size = memory_start + lowmem_size -
+ reg->base;
+ reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT);
+ }
+ }
+
+ /* XXX need to clip this if using highmem? */
+ sparse_memory_present_with_active_regions(0);
+
+#ifdef CONFIG_MMU
+ init_bootmem_done = 1;
+#endif
+ paging_init();
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+ free_reserved_area((void *)start, (void *)end, -1, "initrd");
+}
+#endif
+
+void free_initmem(void)
+{
+ free_initmem_default(-1);
+}
+
+void __init mem_init(void)
+{
+ high_memory = (void *)__va(memory_start + lowmem_size - 1);
+
+ /* this will put all memory onto the freelists */
+ free_all_bootmem();
+#ifdef CONFIG_HIGHMEM
+ highmem_setup();
+#endif
+
+ mem_init_print_info(NULL);
+#ifdef CONFIG_MMU
+ pr_info("Kernel virtual memory layout:\n");
+ pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
+#ifdef CONFIG_HIGHMEM
+ pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
+ PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
+#endif /* CONFIG_HIGHMEM */
+ pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
+ ioremap_bot, ioremap_base);
+ pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
+ (unsigned long)VMALLOC_START, VMALLOC_END);
+#endif
+ mem_init_done = 1;
+}
+
+#ifndef CONFIG_MMU
+int page_is_ram(unsigned long pfn)
+{
+ return __range_ok(pfn, 0);
+}
+#else
+int page_is_ram(unsigned long pfn)
+{
+ return pfn < max_low_pfn;
+}
+
+/*
+ * Check for command-line options that affect what MMU_init will do.
+ */
+static void mm_cmdline_setup(void)
+{
+ unsigned long maxmem = 0;
+ char *p = cmd_line;
+
+ /* Look for mem= option on command line */
+ p = strstr(cmd_line, "mem=");
+ if (p) {
+ p += 4;
+ maxmem = memparse(p, &p);
+ if (maxmem && memory_size > maxmem) {
+ memory_size = maxmem;
+ memblock.memory.regions[0].size = memory_size;
+ }
+ }
+}
+
+/*
+ * MMU_init_hw does the chip-specific initialization of the MMU hardware.
+ */
+static void __init mmu_init_hw(void)
+{
+ /*
+ * The Zone Protection Register (ZPR) defines how protection will
+ * be applied to every page which is a member of a given zone. At
+ * present, we utilize only two of the zones.
+ * The zone index bits (of ZSEL) in the PTE are used for software
+ * indicators, except the LSB. For user access, zone 1 is used,
+ * for kernel access, zone 0 is used. We set all but zone 1
+ * to zero, allowing only kernel access as indicated in the PTE.
+ * For zone 1, we set a 01 binary (a value of 10 will not work)
+ * to allow user access as indicated in the PTE. This also allows
+ * kernel access as indicated in the PTE.
+ */
+ __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
+ "mts rzpr, r11;"
+ : : : "r11");
+}
+
+/*
+ * MMU_init sets up the basic memory mappings for the kernel,
+ * including both RAM and possibly some I/O regions,
+ * and sets up the page tables and the MMU hardware ready to go.
+ */
+
+/* called from head.S */
+asmlinkage void __init mmu_init(void)
+{
+ unsigned int kstart, ksize;
+
+ if (!memblock.reserved.cnt) {
+ pr_emerg("Error memory count\n");
+ machine_restart(NULL);
+ }
+
+ if ((u32) memblock.memory.regions[0].size < 0x400000) {
+ pr_emerg("Memory must be greater than 4MB\n");
+ machine_restart(NULL);
+ }
+
+ if ((u32) memblock.memory.regions[0].size < kernel_tlb) {
+ pr_emerg("Kernel size is greater than memory node\n");
+ machine_restart(NULL);
+ }
+
+ /* Find main memory where the kernel is */
+ memory_start = (u32) memblock.memory.regions[0].base;
+ lowmem_size = memory_size = (u32) memblock.memory.regions[0].size;
+
+ if (lowmem_size > CONFIG_LOWMEM_SIZE) {
+ lowmem_size = CONFIG_LOWMEM_SIZE;
+#ifndef CONFIG_HIGHMEM
+ memory_size = lowmem_size;
+#endif
+ }
+
+ mm_cmdline_setup(); /* FIXME parse args from command line - not used */
+
+ /*
+ * Map out the kernel text/data/bss from the available physical
+ * memory.
+ */
+ kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
+ /* kernel size */
+ ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
+ memblock_reserve(kstart, ksize);
+
+#if defined(CONFIG_BLK_DEV_INITRD)
+ /* Remove the init RAM disk from the available memory. */
+ if (initrd_start) {
+ unsigned long size;
+ size = initrd_end - initrd_start;
+ memblock_reserve(__virt_to_phys(initrd_start), size);
+ }
+#endif /* CONFIG_BLK_DEV_INITRD */
+
+ /* Initialize the MMU hardware */
+ mmu_init_hw();
+
+ /* Map in all of RAM starting at CONFIG_KERNEL_START */
+ mapin_ram();
+
+ /* Extend vmalloc and ioremap area as big as possible */
+#ifdef CONFIG_HIGHMEM
+ ioremap_base = ioremap_bot = PKMAP_BASE;
+#else
+ ioremap_base = ioremap_bot = FIXADDR_START;
+#endif
+
+ /* Initialize the context management stuff */
+ mmu_context_init();
+
+ /* Shortly after that, the entire linear mapping will be available */
+ /* This will also cause that unflatten device tree will be allocated
+ * inside 768MB limit */
+ memblock_set_current_limit(memory_start + lowmem_size - 1);
+}
+
+/* This is only called until mem_init is done. */
+void __init *early_get_page(void)
+{
+ void *p;
+ if (init_bootmem_done) {
+ p = alloc_bootmem_pages(PAGE_SIZE);
+ } else {
+ /*
+ * Mem start + kernel_tlb -> here is limit
+ * because of mem mapping from head.S
+ */
+ p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE,
+ memory_start + kernel_tlb));
+ }
+ return p;
+}
+
+#endif /* CONFIG_MMU */
+
+void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask)
+{
+ if (mem_init_done)
+ return kmalloc(size, mask);
+ else
+ return alloc_bootmem(size);
+}
+
+void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask)
+{
+ void *p;
+
+ if (mem_init_done)
+ p = kzalloc(size, mask);
+ else {
+ p = alloc_bootmem(size);
+ if (p)
+ memset(p, 0, size);
+ }
+ return p;
+}
diff --git a/arch/microblaze/mm/mmu_context.c b/arch/microblaze/mm/mmu_context.c
new file mode 100644
index 0000000..26ff82f
--- /dev/null
+++ b/arch/microblaze/mm/mmu_context.c
@@ -0,0 +1,70 @@
+/*
+ * This file contains the routines for handling the MMU.
+ *
+ * Copyright (C) 2007 Xilinx, Inc. All rights reserved.
+ *
+ * Derived from arch/ppc/mm/4xx_mmu.c:
+ * -- paulus
+ *
+ * Derived from arch/ppc/mm/init.c:
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ * and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ * Copyright (C) 1996 Paul Mackerras
+ * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ *
+ * Derived from "arch/i386/mm/init.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/mm.h>
+#include <linux/init.h>
+
+#include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
+
+mm_context_t next_mmu_context;
+unsigned long context_map[LAST_CONTEXT / BITS_PER_LONG + 1];
+atomic_t nr_free_contexts;
+struct mm_struct *context_mm[LAST_CONTEXT+1];
+
+/*
+ * Initialize the context management stuff.
+ */
+void __init mmu_context_init(void)
+{
+ /*
+ * The use of context zero is reserved for the kernel.
+ * This code assumes FIRST_CONTEXT < 32.
+ */
+ context_map[0] = (1 << FIRST_CONTEXT) - 1;
+ next_mmu_context = FIRST_CONTEXT;
+ atomic_set(&nr_free_contexts, LAST_CONTEXT - FIRST_CONTEXT + 1);
+}
+
+/*
+ * Steal a context from a task that has one at the moment.
+ *
+ * This isn't an LRU system, it just frees up each context in
+ * turn (sort-of pseudo-random replacement :). This would be the
+ * place to implement an LRU scheme if anyone were motivated to do it.
+ */
+void steal_context(void)
+{
+ struct mm_struct *mm;
+
+ /* free up context `next_mmu_context' */
+ /* if we shouldn't free context 0, don't... */
+ if (next_mmu_context < FIRST_CONTEXT)
+ next_mmu_context = FIRST_CONTEXT;
+ mm = context_mm[next_mmu_context];
+ flush_tlb_mm(mm);
+ destroy_context(mm);
+}
diff --git a/arch/microblaze/mm/pgtable.c b/arch/microblaze/mm/pgtable.c
new file mode 100644
index 0000000..4f4520e
--- /dev/null
+++ b/arch/microblaze/mm/pgtable.c
@@ -0,0 +1,260 @@
+/*
+ * This file contains the routines setting up the linux page tables.
+ *
+ * Copyright (C) 2008 Michal Simek
+ * Copyright (C) 2008 PetaLogix
+ *
+ * Copyright (C) 2007 Xilinx, Inc. All rights reserved.
+ *
+ * Derived from arch/ppc/mm/pgtable.c:
+ * -- paulus
+ *
+ * Derived from arch/ppc/mm/init.c:
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ * and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ * Copyright (C) 1996 Paul Mackerras
+ * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ *
+ * Derived from "arch/i386/mm/init.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <linux/io.h>
+#include <asm/mmu.h>
+#include <asm/sections.h>
+#include <asm/fixmap.h>
+
+unsigned long ioremap_base;
+unsigned long ioremap_bot;
+EXPORT_SYMBOL(ioremap_bot);
+
+#ifndef CONFIG_SMP
+struct pgtable_cache_struct quicklists;
+#endif
+
+static void __iomem *__ioremap(phys_addr_t addr, unsigned long size,
+ unsigned long flags)
+{
+ unsigned long v, i;
+ phys_addr_t p;
+ int err;
+
+ /*
+ * Choose an address to map it to.
+ * Once the vmalloc system is running, we use it.
+ * Before then, we use space going down from ioremap_base
+ * (ioremap_bot records where we're up to).
+ */
+ p = addr & PAGE_MASK;
+ size = PAGE_ALIGN(addr + size) - p;
+
+ /*
+ * Don't allow anybody to remap normal RAM that we're using.
+ * mem_init() sets high_memory so only do the check after that.
+ *
+ * However, allow remap of rootfs: TBD
+ */
+
+ if (mem_init_done &&
+ p >= memory_start && p < virt_to_phys(high_memory) &&
+ !(p >= __virt_to_phys((phys_addr_t)__bss_stop) &&
+ p < __virt_to_phys((phys_addr_t)__bss_stop))) {
+ pr_warn("__ioremap(): phys addr "PTE_FMT" is RAM lr %pf\n",
+ (unsigned long)p, __builtin_return_address(0));
+ return NULL;
+ }
+
+ if (size == 0)
+ return NULL;
+
+ /*
+ * Is it already mapped? If the whole area is mapped then we're
+ * done, otherwise remap it since we want to keep the virt addrs for
+ * each request contiguous.
+ *
+ * We make the assumption here that if the bottom and top
+ * of the range we want are mapped then it's mapped to the
+ * same virt address (and this is contiguous).
+ * -- Cort
+ */
+
+ if (mem_init_done) {
+ struct vm_struct *area;
+ area = get_vm_area(size, VM_IOREMAP);
+ if (area == NULL)
+ return NULL;
+ v = (unsigned long) area->addr;
+ } else {
+ v = (ioremap_bot -= size);
+ }
+
+ if ((flags & _PAGE_PRESENT) == 0)
+ flags |= _PAGE_KERNEL;
+ if (flags & _PAGE_NO_CACHE)
+ flags |= _PAGE_GUARDED;
+
+ err = 0;
+ for (i = 0; i < size && err == 0; i += PAGE_SIZE)
+ err = map_page(v + i, p + i, flags);
+ if (err) {
+ if (mem_init_done)
+ vfree((void *)v);
+ return NULL;
+ }
+
+ return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
+}
+
+void __iomem *ioremap(phys_addr_t addr, unsigned long size)
+{
+ return __ioremap(addr, size, _PAGE_NO_CACHE);
+}
+EXPORT_SYMBOL(ioremap);
+
+void iounmap(void __iomem *addr)
+{
+ if ((__force void *)addr > high_memory &&
+ (unsigned long) addr < ioremap_bot)
+ vfree((void *) (PAGE_MASK & (unsigned long) addr));
+}
+EXPORT_SYMBOL(iounmap);
+
+
+int map_page(unsigned long va, phys_addr_t pa, int flags)
+{
+ pmd_t *pd;
+ pte_t *pg;
+ int err = -ENOMEM;
+ /* Use upper 10 bits of VA to index the first level map */
+ pd = pmd_offset(pgd_offset_k(va), va);
+ /* Use middle 10 bits of VA to index the second-level map */
+ pg = pte_alloc_kernel(pd, va); /* from powerpc - pgtable.c */
+ /* pg = pte_alloc_kernel(&init_mm, pd, va); */
+
+ if (pg != NULL) {
+ err = 0;
+ set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
+ __pgprot(flags)));
+ if (unlikely(mem_init_done))
+ _tlbie(va);
+ }
+ return err;
+}
+
+/*
+ * Map in all of physical memory starting at CONFIG_KERNEL_START.
+ */
+void __init mapin_ram(void)
+{
+ unsigned long v, p, s, f;
+
+ v = CONFIG_KERNEL_START;
+ p = memory_start;
+ for (s = 0; s < lowmem_size; s += PAGE_SIZE) {
+ f = _PAGE_PRESENT | _PAGE_ACCESSED |
+ _PAGE_SHARED | _PAGE_HWEXEC;
+ if ((char *) v < _stext || (char *) v >= _etext)
+ f |= _PAGE_WRENABLE;
+ else
+ /* On the MicroBlaze, no user access
+ forces R/W kernel access */
+ f |= _PAGE_USER;
+ map_page(v, p, f);
+ v += PAGE_SIZE;
+ p += PAGE_SIZE;
+ }
+}
+
+/* is x a power of 2? */
+#define is_power_of_2(x) ((x) != 0 && (((x) & ((x) - 1)) == 0))
+
+/* Scan the real Linux page tables and return a PTE pointer for
+ * a virtual address in a context.
+ * Returns true (1) if PTE was found, zero otherwise. The pointer to
+ * the PTE pointer is unmodified if PTE is not found.
+ */
+static int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep)
+{
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+ int retval = 0;
+
+ pgd = pgd_offset(mm, addr & PAGE_MASK);
+ if (pgd) {
+ pmd = pmd_offset(pgd, addr & PAGE_MASK);
+ if (pmd_present(*pmd)) {
+ pte = pte_offset_kernel(pmd, addr & PAGE_MASK);
+ if (pte) {
+ retval = 1;
+ *ptep = pte;
+ }
+ }
+ }
+ return retval;
+}
+
+/* Find physical address for this virtual address. Normally used by
+ * I/O functions, but anyone can call it.
+ */
+unsigned long iopa(unsigned long addr)
+{
+ unsigned long pa;
+
+ pte_t *pte;
+ struct mm_struct *mm;
+
+ /* Allow mapping of user addresses (within the thread)
+ * for DMA if necessary.
+ */
+ if (addr < TASK_SIZE)
+ mm = current->mm;
+ else
+ mm = &init_mm;
+
+ pa = 0;
+ if (get_pteptr(mm, addr, &pte))
+ pa = (pte_val(*pte) & PAGE_MASK) | (addr & ~PAGE_MASK);
+
+ return pa;
+}
+
+__init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
+ unsigned long address)
+{
+ pte_t *pte;
+ if (mem_init_done) {
+ pte = (pte_t *)__get_free_page(GFP_KERNEL |
+ __GFP_REPEAT | __GFP_ZERO);
+ } else {
+ pte = (pte_t *)early_get_page();
+ if (pte)
+ clear_page(pte);
+ }
+ return pte;
+}
+
+void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
+{
+ unsigned long address = __fix_to_virt(idx);
+
+ if (idx >= __end_of_fixed_addresses)
+ BUG();
+
+ map_page(address, phys, pgprot_val(flags));
+}