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, 305 insertions, 0 deletions

diff --git a/include/asm-arm26/pgtable.h b/include/asm-arm26/pgtable.h
new file mode 100644
index 0000000..af0b890
--- /dev/null
+++ b/include/asm-arm26/pgtable.h
@@ -0,0 +1,305 @@
+/*
+ *  linux/include/asm-arm26/pgtable.h
+ *
+ *  Copyright (C) 2000-2002 Russell King
+ *  Copyright (C) 2003 Ian Molton
+ *
+ * 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.
+ */
+#ifndef _ASMARM_PGTABLE_H
+#define _ASMARM_PGTABLE_H
+
+#include <asm-generic/4level-fixup.h>
+
+#include <linux/config.h>
+#include <asm/memory.h>
+
+/*
+ * The table below defines the page protection levels that we insert into our
+ * Linux page table version.  These get translated into the best that the
+ * architecture can perform.  Note that on most ARM hardware:
+ *  1) We cannot do execute protection
+ *  2) If we could do execute protection, then read is implied
+ *  3) write implies read permissions
+ */
+#define __P000  PAGE_NONE
+#define __P001  PAGE_READONLY
+#define __P010  PAGE_COPY
+#define __P011  PAGE_COPY
+#define __P100  PAGE_READONLY
+#define __P101  PAGE_READONLY
+#define __P110  PAGE_COPY
+#define __P111  PAGE_COPY
+
+#define __S000  PAGE_NONE
+#define __S001  PAGE_READONLY
+#define __S010  PAGE_SHARED
+#define __S011  PAGE_SHARED
+#define __S100  PAGE_READONLY
+#define __S101  PAGE_READONLY
+#define __S110  PAGE_SHARED
+#define __S111  PAGE_SHARED
+
+/*
+ * PMD_SHIFT determines the size of the area a second-level page table can map
+ * PGDIR_SHIFT determines what a third-level page table entry can map
+ */
+#define PGD_SHIFT		25
+#define PMD_SHIFT		20
+
+#define PGD_SIZE                (1UL << PGD_SHIFT)
+#define PGD_MASK                (~(PGD_SIZE-1))
+#define PMD_SIZE                (1UL << PMD_SHIFT)
+#define PMD_MASK                (~(PMD_SIZE-1))
+
+/* The kernel likes to use these names for the above (ick) */
+#define PGDIR_SIZE PGD_SIZE
+#define PGDIR_MASK PGD_MASK
+
+#define PTRS_PER_PGD            32
+#define PTRS_PER_PMD            1
+#define PTRS_PER_PTE            32
+
+#define FIRST_USER_PGD_NR       1
+#define USER_PTRS_PER_PGD       ((TASK_SIZE/PGD_SIZE) - FIRST_USER_PGD_NR)
+
+// FIXME - WTF?
+#define LIBRARY_TEXT_START	0x0c000000
+
+
+
+#ifndef __ASSEMBLY__
+extern void __pte_error(const char *file, int line, unsigned long val);
+extern void __pmd_error(const char *file, int line, unsigned long val);
+extern void __pgd_error(const char *file, int line, unsigned long val);
+
+#define pte_ERROR(pte)		__pte_error(__FILE__, __LINE__, pte_val(pte))
+#define pmd_ERROR(pmd)		__pmd_error(__FILE__, __LINE__, pmd_val(pmd))
+#define pgd_ERROR(pgd)		__pgd_error(__FILE__, __LINE__, pgd_val(pgd))
+
+/*
+ * ZERO_PAGE is a global shared page that is always zero: used
+ * for zero-mapped memory areas etc..
+ */
+extern struct page *empty_zero_page;
+#define ZERO_PAGE(vaddr)	(empty_zero_page)
+
+#define pte_pfn(pte)		(pte_val(pte) >> PAGE_SHIFT)
+#define pte_page(pte)           (pfn_to_page(pte_pfn(pte)))
+#define pfn_pte(pfn,prot)	(__pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot)))
+#define pages_to_mb(x)		((x) >> (20 - PAGE_SHIFT))
+#define mk_pte(page,prot)	pfn_pte(page_to_pfn(page),prot)
+#define page_pte_prot(page,prot)	mk_pte(page, prot)
+#define page_pte(page)		mk_pte(page, __pgprot(0))
+
+/*
+ * Terminology: PGD = Page Directory, PMD = Page Middle Directory,
+ *              PTE = Page Table Entry
+ *
+ * on arm26 we have no 2nd level page table. we simulate this by removing the
+ * PMD.
+ *
+ * pgd_none is 0 to prevernt pmd_alloc() calling __pmd_alloc(). This causes it
+ * to return pmd_offset(pgd,addr) which is a pointer to the pgd (IOW, a no-op).
+ *
+ * however, to work this way, whilst we are allocating 32 pgds, containing 32
+ * PTEs, the actual work is done on the PMDs, thus:
+ *
+ * instead of  mm->pgd->pmd->pte
+ * we have     mm->pgdpmd->pte
+ *
+ * IOW, think of PGD operations and PMD ones as being the same thing, just
+ * that PGD stuff deals with the mm_struct side of things, wheras PMD stuff
+ * deals with the pte side of things.
+ *
+ * additionally, we store some bits in the PGD and PTE pointers: 
+ * PGDs:
+ *   o The lowest (1) bit of the PGD is to determine if it is present or swap.
+ *   o The 2nd bit of the PGD is unused and must be zero.
+ *   o The top 6 bits of the PGD must be zero. 
+ * PTEs:
+ *   o The lower 5 bits of a pte are flags. bit 1 is the 'present' flag. The
+ *     others determine the pages attributes.
+ *
+ * the pgd_val, pmd_val, and pte_val macros seem to be private to our code.
+ * They get the RAW value of the PGD/PMD/PTE entry, including our flags
+ * encoded into the pointers.
+ * 
+ * The pgd_offset, pmd_offset, and pte_offset macros are used by the kernel,
+ * so they shouldnt have our flags attached.
+ *
+ * If you understood that, feel free to explain it to me...
+ *
+ */
+
+#define _PMD_PRESENT     (0x01)
+
+/* These definitions allow us to optimise out stuff like pmd_alloc() */
+#define pgd_none(pgd)		(0) 
+#define pgd_bad(pgd)		(0)
+#define pgd_present(pgd)	(1)
+#define pgd_clear(pgdp)		do { } while (0)
+
+/* Whilst these handle our actual 'page directory' (the agglomeration of pgd and pmd)
+ */
+#define pmd_none(pmd)           (!pmd_val(pmd))
+#define pmd_bad(pmd)            ((pmd_val(pmd) & 0xfc000002))
+#define pmd_present(pmd)        (pmd_val(pmd) & _PMD_PRESENT)
+#define set_pmd(pmd_ptr, pmd)   ((*(pmd_ptr)) = (pmd))
+#define pmd_clear(pmdp)         set_pmd(pmdp, __pmd(0))
+
+/* and these handle our pte tables */
+#define pte_none(pte)           (!pte_val(pte))
+#define pte_present(pte)        (pte_val(pte) & _PAGE_PRESENT)
+#define set_pte(pte_ptr, pte)   ((*(pte_ptr)) = (pte))
+#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
+#define pte_clear(mm,addr,ptep)	set_pte_at((mm),(addr),(ptep), __pte(0))
+
+/* macros to ease the getting of pointers to stuff... */
+#define pgd_offset(mm, addr)	((pgd_t *)(mm)->pgd        + __pgd_index(addr))
+#define pmd_offset(pgd, addr)	((pmd_t *)(pgd))
+#define pte_offset(pmd, addr)   ((pte_t *)pmd_page(*(pmd)) + __pte_index(addr))
+
+/* there is no __pmd_index as we dont use pmds */
+#define __pgd_index(addr)	((addr) >> PGD_SHIFT)
+#define __pte_index(addr)	(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
+
+
+/* Keep the kernel happy */
+#define pgd_index(addr)         __pgd_index(addr)
+#define pgd_offset_k(addr)	(pgd_offset(&init_mm, addr))
+
+/*
+ * The vmalloc() routines leaves a hole of 4kB between each vmalloced
+ * area for the same reason. ;) FIXME: surely 1 page not 4k ?
+ */
+#define VMALLOC_START     0x01a00000
+#define VMALLOC_END       0x01c00000
+
+/* Is pmd_page supposed to return a pointer to a page in some arches? ours seems to
+ * return a pointer to memory (no special alignment)
+ */
+#define pmd_page(pmd)  ((struct page *)(pmd_val((pmd)) & ~_PMD_PRESENT))
+#define pmd_page_kernel(pmd) ((pte_t *)(pmd_val((pmd)) & ~_PMD_PRESENT))
+
+#define pte_offset_kernel(dir,addr)     (pmd_page_kernel(*(dir)) + __pte_index(addr))
+
+#define pte_offset_map(dir,addr)        (pmd_page_kernel(*(dir)) + __pte_index(addr))
+#define pte_offset_map_nested(dir,addr) (pmd_page_kernel(*(dir)) + __pte_index(addr))
+#define pte_unmap(pte)                  do { } while (0)
+#define pte_unmap_nested(pte)           do { } while (0)
+
+
+#define _PAGE_PRESENT   0x01
+#define _PAGE_READONLY  0x02
+#define _PAGE_NOT_USER  0x04
+#define _PAGE_OLD       0x08
+#define _PAGE_CLEAN     0x10
+
+// an old page has never been read.
+// a clean page has never been written.
+
+/*                               -- present --   -- !dirty --  --- !write ---   ---- !user --- */
+#define PAGE_NONE       __pgprot(_PAGE_PRESENT | _PAGE_CLEAN | _PAGE_READONLY | _PAGE_NOT_USER)
+#define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_CLEAN                                  )
+#define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_CLEAN | _PAGE_READONLY                 )
+#define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_CLEAN | _PAGE_READONLY                 )
+#define PAGE_KERNEL     __pgprot(_PAGE_PRESENT                                | _PAGE_NOT_USER)
+
+#define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_OLD | _PAGE_CLEAN)
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+#define pte_read(pte)                   (!(pte_val(pte) & _PAGE_NOT_USER))
+#define pte_write(pte)                  (!(pte_val(pte) & _PAGE_READONLY))
+#define pte_exec(pte)                   (!(pte_val(pte) & _PAGE_NOT_USER))
+#define pte_dirty(pte)                  (!(pte_val(pte) & _PAGE_CLEAN))
+#define pte_young(pte)                  (!(pte_val(pte) & _PAGE_OLD))
+//ONLY when !pte_present() I think. nicked from arm32 (FIXME!)
+#define pte_file(pte)                   (!(pte_val(pte) & _PAGE_OLD))
+
+#define PTE_BIT_FUNC(fn,op)                     \
+static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
+
+PTE_BIT_FUNC(wrprotect, |=  _PAGE_READONLY);
+PTE_BIT_FUNC(mkwrite,   &= ~_PAGE_READONLY);
+PTE_BIT_FUNC(exprotect, |=  _PAGE_NOT_USER);
+PTE_BIT_FUNC(mkexec,    &= ~_PAGE_NOT_USER);
+PTE_BIT_FUNC(mkclean,   |=  _PAGE_CLEAN);
+PTE_BIT_FUNC(mkdirty,   &= ~_PAGE_CLEAN);
+PTE_BIT_FUNC(mkold,     |=  _PAGE_OLD);
+PTE_BIT_FUNC(mkyoung,   &= ~_PAGE_OLD);
+
+/*
+ * We don't store cache state bits in the page table here. FIXME - or do we?
+ */
+#define pgprot_noncached(prot)  (prot)
+#define pgprot_writecombine(prot) (prot) //FIXME - is a no-op?
+
+extern void pgtable_cache_init(void);
+
+//FIXME - nicked from arm32 and brutally hacked. probably wrong.
+#define pte_to_pgoff(x) (pte_val(x) >> 2)
+#define pgoff_to_pte(x) __pte(((x) << 2) & ~_PAGE_OLD)
+
+//FIXME - next line borrowed from arm32. is it right?
+#define PTE_FILE_MAX_BITS       30
+
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+	pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot);
+	return pte;
+}
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+
+/* Encode and decode a swap entry.
+ *
+ * We support up to 32GB of swap on 4k machines
+ */
+#define __swp_type(x)		(((x).val >> 2) & 0x7f)
+#define __swp_offset(x)		((x).val >> 9)
+#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << 2) | ((offset) << 9) })
+#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
+
+/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
+/* FIXME: this is not correct */
+#define kern_addr_valid(addr)	(1)
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+static inline pte_t mk_pte_phys(unsigned long physpage, pgprot_t pgprot)
+{
+        pte_t pte;
+        pte_val(pte) = physpage | pgprot_val(pgprot);
+        return pte;
+}
+
+
+#include <asm-generic/pgtable.h>
+
+/*
+ * remap a physical address `phys' of size `size' with page protection `prot'
+ * into virtual address `from'
+ */
+#define io_remap_page_range(vma,from,phys,size,prot) \
+		remap_pfn_range(vma, from, (phys) >> PAGE_SHIFT, size, prot)
+
+#define io_remap_pfn_range(vma,from,pfn,size,prot) \
+		remap_pfn_range(vma, from, pfn, size, prot)
+
+#define MK_IOSPACE_PFN(space, pfn)	(pfn)
+#define GET_IOSPACE(pfn)		0
+#define GET_PFN(pfn)			(pfn)
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASMARM_PGTABLE_H */