1 files changed, 480 insertions, 0 deletions

diff --git a/arch/tile/include/asm/pgtable.h b/arch/tile/include/asm/pgtable.h
new file mode 100644
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+++ b/arch/tile/include/asm/pgtable.h
@@ -0,0 +1,480 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ *
+ * This file contains the functions and defines necessary to modify and use
+ * the TILE page table tree.
+ */
+
+#ifndef _ASM_TILE_PGTABLE_H
+#define _ASM_TILE_PGTABLE_H
+
+#include <hv/hypervisor.h>
+
+#ifndef __ASSEMBLY__
+
+#include <linux/bitops.h>
+#include <linux/threads.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <asm/processor.h>
+#include <asm/fixmap.h>
+#include <asm/system.h>
+
+struct mm_struct;
+struct vm_area_struct;
+
+/*
+ * ZERO_PAGE is a global shared page that is always zero: used
+ * for zero-mapped memory areas etc..
+ */
+extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
+#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
+
+extern pgd_t swapper_pg_dir[];
+extern pgprot_t swapper_pgprot;
+extern struct kmem_cache *pgd_cache;
+extern spinlock_t pgd_lock;
+extern struct list_head pgd_list;
+
+/*
+ * The very last slots in the pgd_t are for addresses unusable by Linux
+ * (pgd_addr_invalid() returns true).  So we use them for the list structure.
+ * The x86 code we are modelled on uses the page->private/index fields
+ * (older 2.6 kernels) or the lru list (newer 2.6 kernels), but since
+ * our pgds are so much smaller than a page, it seems a waste to
+ * spend a whole page on each pgd.
+ */
+#define PGD_LIST_OFFSET \
+  ((PTRS_PER_PGD * sizeof(pgd_t)) - sizeof(struct list_head))
+#define pgd_to_list(pgd) \
+  ((struct list_head *)((char *)(pgd) + PGD_LIST_OFFSET))
+#define list_to_pgd(list) \
+  ((pgd_t *)((char *)(list) - PGD_LIST_OFFSET))
+
+extern void pgtable_cache_init(void);
+extern void paging_init(void);
+extern void set_page_homes(void);
+
+#define FIRST_USER_ADDRESS      0
+
+#define _PAGE_PRESENT           HV_PTE_PRESENT
+#define _PAGE_HUGE_PAGE         HV_PTE_PAGE
+#define _PAGE_READABLE          HV_PTE_READABLE
+#define _PAGE_WRITABLE          HV_PTE_WRITABLE
+#define _PAGE_EXECUTABLE        HV_PTE_EXECUTABLE
+#define _PAGE_ACCESSED          HV_PTE_ACCESSED
+#define _PAGE_DIRTY             HV_PTE_DIRTY
+#define _PAGE_GLOBAL            HV_PTE_GLOBAL
+#define _PAGE_USER              HV_PTE_USER
+
+/*
+ * All the "standard" bits.  Cache-control bits are managed elsewhere.
+ * This is used to test for valid level-2 page table pointers by checking
+ * all the bits, and to mask away the cache control bits for mprotect.
+ */
+#define _PAGE_ALL (\
+  _PAGE_PRESENT | \
+  _PAGE_HUGE_PAGE | \
+  _PAGE_READABLE | \
+  _PAGE_WRITABLE | \
+  _PAGE_EXECUTABLE | \
+  _PAGE_ACCESSED | \
+  _PAGE_DIRTY | \
+  _PAGE_GLOBAL | \
+  _PAGE_USER \
+)
+
+#define PAGE_NONE \
+        __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED)
+#define PAGE_SHARED \
+        __pgprot(_PAGE_PRESENT | _PAGE_READABLE | _PAGE_WRITABLE | \
+                 _PAGE_USER | _PAGE_ACCESSED)
+
+#define PAGE_SHARED_EXEC \
+        __pgprot(_PAGE_PRESENT | _PAGE_READABLE | _PAGE_WRITABLE | \
+                 _PAGE_EXECUTABLE | _PAGE_USER | _PAGE_ACCESSED)
+#define PAGE_COPY_NOEXEC \
+        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_READABLE)
+#define PAGE_COPY_EXEC \
+        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | \
+                 _PAGE_READABLE | _PAGE_EXECUTABLE)
+#define PAGE_COPY \
+        PAGE_COPY_NOEXEC
+#define PAGE_READONLY \
+        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_READABLE)
+#define PAGE_READONLY_EXEC \
+        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | \
+                 _PAGE_READABLE | _PAGE_EXECUTABLE)
+
+#define _PAGE_KERNEL_RO \
+ (_PAGE_PRESENT | _PAGE_GLOBAL | _PAGE_READABLE | _PAGE_ACCESSED)
+#define _PAGE_KERNEL \
+ (_PAGE_KERNEL_RO | _PAGE_WRITABLE | _PAGE_DIRTY)
+#define _PAGE_KERNEL_EXEC       (_PAGE_KERNEL_RO | _PAGE_EXECUTABLE)
+
+#define PAGE_KERNEL             __pgprot(_PAGE_KERNEL)
+#define PAGE_KERNEL_RO          __pgprot(_PAGE_KERNEL_RO)
+#define PAGE_KERNEL_EXEC        __pgprot(_PAGE_KERNEL_EXEC)
+
+#define page_to_kpgprot(p) PAGE_KERNEL
+
+/*
+ * We could tighten these up, but for now writable or executable
+ * implies readable.
+ */
+#define __P000  PAGE_NONE
+#define __P001  PAGE_READONLY
+#define __P010  PAGE_COPY      /* this is write-only, which we won't support */
+#define __P011  PAGE_COPY
+#define __P100  PAGE_READONLY_EXEC
+#define __P101  PAGE_READONLY_EXEC
+#define __P110  PAGE_COPY_EXEC
+#define __P111  PAGE_COPY_EXEC
+
+#define __S000  PAGE_NONE
+#define __S001  PAGE_READONLY
+#define __S010  PAGE_SHARED
+#define __S011  PAGE_SHARED
+#define __S100  PAGE_READONLY_EXEC
+#define __S101  PAGE_READONLY_EXEC
+#define __S110  PAGE_SHARED_EXEC
+#define __S111  PAGE_SHARED_EXEC
+
+/*
+ * All the normal _PAGE_ALL bits are ignored for PMDs, except PAGE_PRESENT
+ * and PAGE_HUGE_PAGE, which must be one and zero, respectively.
+ * We set the ignored bits to zero.
+ */
+#define _PAGE_TABLE     _PAGE_PRESENT
+
+/* Inherit the caching flags from the old protection bits. */
+#define pgprot_modify(oldprot, newprot) \
+  (pgprot_t) { ((oldprot).val & ~_PAGE_ALL) | (newprot).val }
+
+/* Just setting the PFN to zero suffices. */
+#define pte_pgprot(x) hv_pte_set_pfn((x), 0)
+
+/*
+ * For PTEs and PDEs, we must clear the Present bit first when
+ * clearing a page table entry, so clear the bottom half first and
+ * enforce ordering with a barrier.
+ */
+static inline void __pte_clear(pte_t *ptep)
+{
+#ifdef __tilegx__
+        ptep->val = 0;
+#else
+        u32 *tmp = (u32 *)ptep;
+        tmp[0] = 0;
+        barrier();
+        tmp[1] = 0;
+#endif
+}
+#define pte_clear(mm, addr, ptep) __pte_clear(ptep)
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+#define pte_present hv_pte_get_present
+#define pte_user hv_pte_get_user
+#define pte_read hv_pte_get_readable
+#define pte_dirty hv_pte_get_dirty
+#define pte_young hv_pte_get_accessed
+#define pte_write hv_pte_get_writable
+#define pte_exec hv_pte_get_executable
+#define pte_huge hv_pte_get_page
+#define pte_rdprotect hv_pte_clear_readable
+#define pte_exprotect hv_pte_clear_executable
+#define pte_mkclean hv_pte_clear_dirty
+#define pte_mkold hv_pte_clear_accessed
+#define pte_wrprotect hv_pte_clear_writable
+#define pte_mksmall hv_pte_clear_page
+#define pte_mkread hv_pte_set_readable
+#define pte_mkexec hv_pte_set_executable
+#define pte_mkdirty hv_pte_set_dirty
+#define pte_mkyoung hv_pte_set_accessed
+#define pte_mkwrite hv_pte_set_writable
+#define pte_mkhuge hv_pte_set_page
+
+#define pte_special(pte) 0
+#define pte_mkspecial(pte) (pte)
+
+/*
+ * Use some spare bits in the PTE for user-caching tags.
+ */
+#define pte_set_forcecache hv_pte_set_client0
+#define pte_get_forcecache hv_pte_get_client0
+#define pte_clear_forcecache hv_pte_clear_client0
+#define pte_set_anyhome hv_pte_set_client1
+#define pte_get_anyhome hv_pte_get_client1
+#define pte_clear_anyhome hv_pte_clear_client1
+
+/*
+ * A migrating PTE has PAGE_PRESENT clear but all the other bits preserved.
+ */
+#define pte_migrating hv_pte_get_migrating
+#define pte_mkmigrate(x) hv_pte_set_migrating(hv_pte_clear_present(x))
+#define pte_donemigrate(x) hv_pte_set_present(hv_pte_clear_migrating(x))
+
+#define pte_ERROR(e) \
+        pr_err("%s:%d: bad pte 0x%016llx.\n", __FILE__, __LINE__, pte_val(e))
+#define pgd_ERROR(e) \
+        pr_err("%s:%d: bad pgd 0x%016llx.\n", __FILE__, __LINE__, pgd_val(e))
+
+/*
+ * set_pte_order() sets the given PTE and also sanity-checks the
+ * requested PTE against the page homecaching.  Unspecified parts
+ * of the PTE are filled in when it is written to memory, i.e. all
+ * caching attributes if "!forcecache", or the home cpu if "anyhome".
+ */
+extern void set_pte_order(pte_t *ptep, pte_t pte, int order);
+
+#define set_pte(ptep, pteval) set_pte_order(ptep, pteval, 0)
+#define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
+#define set_pte_atomic(pteptr, pteval) set_pte(pteptr, pteval)
+
+#define pte_page(x)             pfn_to_page(pte_pfn(x))
+
+static inline int pte_none(pte_t pte)
+{
+        return !pte.val;
+}
+
+static inline unsigned long pte_pfn(pte_t pte)
+{
+        return hv_pte_get_pfn(pte);
+}
+
+/* Set or get the remote cache cpu in a pgprot with remote caching. */
+extern pgprot_t set_remote_cache_cpu(pgprot_t prot, int cpu);
+extern int get_remote_cache_cpu(pgprot_t prot);
+
+static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot)
+{
+        return hv_pte_set_pfn(prot, pfn);
+}
+
+/* Support for priority mappings. */
+extern void start_mm_caching(struct mm_struct *mm);
+extern void check_mm_caching(struct mm_struct *prev, struct mm_struct *next);
+
+/*
+ * Support non-linear file mappings (see sys_remap_file_pages).
+ * This is defined by CLIENT1 set but CLIENT0 and _PAGE_PRESENT clear, and the
+ * file offset in the 32 high bits.
+ */
+#define _PAGE_FILE        HV_PTE_CLIENT1
+#define PTE_FILE_MAX_BITS 32
+#define pte_file(pte)     (hv_pte_get_client1(pte) && !hv_pte_get_client0(pte))
+#define pte_to_pgoff(pte) ((pte).val >> 32)
+#define pgoff_to_pte(off) ((pte_t) { (((long long)(off)) << 32) | _PAGE_FILE })
+
+/*
+ * Encode and de-code a swap entry (see <linux/swapops.h>).
+ * We put the swap file type+offset in the 32 high bits;
+ * I believe we can just leave the low bits clear.
+ */
+#define __swp_type(swp)         ((swp).val & 0x1f)
+#define __swp_offset(swp)       ((swp).val >> 5)
+#define __swp_entry(type, off)  ((swp_entry_t) { (type) | ((off) << 5) })
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { (pte).val >> 32 })
+#define __swp_entry_to_pte(swp) ((pte_t) { (((long long) ((swp).val)) << 32) })
+
+/*
+ * clone_pgd_range(pgd_t *dst, pgd_t *src, int count);
+ *
+ *  dst - pointer to pgd range anwhere on a pgd page
+ *  src - ""
+ *  count - the number of pgds to copy.
+ *
+ * dst and src can be on the same page, but the range must not overlap,
+ * and must not cross a page boundary.
+ */
+static inline void clone_pgd_range(pgd_t *dst, pgd_t *src, int count)
+{
+       memcpy(dst, src, count * sizeof(pgd_t));
+}
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+
+#define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
+
+/*
+ * If we are doing an mprotect(), just accept the new vma->vm_page_prot
+ * value and combine it with the PFN from the old PTE to get a new PTE.
+ */
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+        return pfn_pte(hv_pte_get_pfn(pte), newprot);
+}
+
+/*
+ * The pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
+ *
+ * This macro returns the index of the entry in the pgd page which would
+ * control the given virtual address.
+ */
+#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
+
+/*
+ * pgd_offset() returns a (pgd_t *)
+ * pgd_index() is used get the offset into the pgd page's array of pgd_t's.
+ */
+#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
+
+/*
+ * A shortcut which implies the use of the kernel's pgd, instead
+ * of a process's.
+ */
+#define pgd_offset_k(address) pgd_offset(&init_mm, address)
+
+#if defined(CONFIG_HIGHPTE)
+extern pte_t *_pte_offset_map(pmd_t *, unsigned long address, enum km_type);
+#define pte_offset_map(dir, address) \
+        _pte_offset_map(dir, address, KM_PTE0)
+#define pte_offset_map_nested(dir, address) \
+        _pte_offset_map(dir, address, KM_PTE1)
+#define pte_unmap(pte) kunmap_atomic(pte, KM_PTE0)
+#define pte_unmap_nested(pte) kunmap_atomic(pte, KM_PTE1)
+#else
+#define pte_offset_map(dir, address) pte_offset_kernel(dir, address)
+#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
+#define pte_unmap(pte) do { } while (0)
+#define pte_unmap_nested(pte) do { } while (0)
+#endif
+
+/* Clear a non-executable kernel PTE and flush it from the TLB. */
+#define kpte_clear_flush(ptep, vaddr)           \
+do {                                            \
+        pte_clear(&init_mm, (vaddr), (ptep));   \
+        local_flush_tlb_page(FLUSH_NONEXEC, (vaddr), PAGE_SIZE); \
+} while (0)
+
+/*
+ * The kernel page tables contain what we need, and we flush when we
+ * change specific page table entries.
+ */
+#define update_mmu_cache(vma, address, pte) do { } while (0)
+
+#ifdef CONFIG_FLATMEM
+#define kern_addr_valid(addr)   (1)
+#endif /* CONFIG_FLATMEM */
+
+#define io_remap_pfn_range(vma, vaddr, pfn, size, prot)         \
+                remap_pfn_range(vma, vaddr, pfn, size, prot)
+
+extern void vmalloc_sync_all(void);
+
+#endif /* !__ASSEMBLY__ */
+
+#ifdef __tilegx__
+#include <asm/pgtable_64.h>
+#else
+#include <asm/pgtable_32.h>
+#endif
+
+#ifndef __ASSEMBLY__
+
+static inline int pmd_none(pmd_t pmd)
+{
+        /*
+         * Only check low word on 32-bit platforms, since it might be
+         * out of sync with upper half.
+         */
+        return (unsigned long)pmd_val(pmd) == 0;
+}
+
+static inline int pmd_present(pmd_t pmd)
+{
+        return pmd_val(pmd) & _PAGE_PRESENT;
+}
+
+static inline int pmd_bad(pmd_t pmd)
+{
+        return ((pmd_val(pmd) & _PAGE_ALL) != _PAGE_TABLE);
+}
+
+static inline unsigned long pages_to_mb(unsigned long npg)
+{
+        return npg >> (20 - PAGE_SHIFT);
+}
+
+/*
+ * The pmd can be thought of an array like this: pmd_t[PTRS_PER_PMD]
+ *
+ * This function returns the index of the entry in the pmd which would
+ * control the given virtual address.
+ */
+static inline unsigned long pmd_index(unsigned long address)
+{
+        return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
+}
+
+/*
+ * A given kernel pmd_t maps to a specific virtual address (either a
+ * kernel huge page or a kernel pte_t table).  Since kernel pte_t
+ * tables can be aligned at sub-page granularity, this function can
+ * return non-page-aligned pointers, despite its name.
+ */
+static inline unsigned long pmd_page_vaddr(pmd_t pmd)
+{
+        phys_addr_t pa =
+                (phys_addr_t)pmd_ptfn(pmd) << HV_LOG2_PAGE_TABLE_ALIGN;
+        return (unsigned long)__va(pa);
+}
+
+/*
+ * A pmd_t points to the base of a huge page or to a pte_t array.
+ * If a pte_t array, since we can have multiple per page, we don't
+ * have a one-to-one mapping of pmd_t's to pages.  However, this is
+ * OK for pte_lockptr(), since we just end up with potentially one
+ * lock being used for several pte_t arrays.
+ */
+#define pmd_page(pmd) pfn_to_page(HV_PTFN_TO_PFN(pmd_ptfn(pmd)))
+
+/*
+ * The pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
+ *
+ * This macro returns the index of the entry in the pte page which would
+ * control the given virtual address.
+ */
+static inline unsigned long pte_index(unsigned long address)
+{
+        return (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
+}
+
+static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long address)
+{
+       return (pte_t *)pmd_page_vaddr(*pmd) + pte_index(address);
+}
+
+static inline int pmd_huge_page(pmd_t pmd)
+{
+        return pmd_val(pmd) & _PAGE_HUGE_PAGE;
+}
+
+#include <asm-generic/pgtable.h>
+
+/* Support /proc/NN/pgtable API. */
+struct seq_file;
+int arch_proc_pgtable_show(struct seq_file *m, struct mm_struct *mm,
+                           unsigned long vaddr, pte_t *ptep, void **datap);
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_TILE_PGTABLE_H */