Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 357 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
new file mode 100644
index 000000000..f6a1265fa
--- /dev/null
+++ b/arch/powerpc/include/asm/page.h
@@ -0,0 +1,357 @@
+#ifndef _ASM_POWERPC_PAGE_H
+#define _ASM_POWERPC_PAGE_H
+
+/*
+ * Copyright (C) 2001,2005 IBM Corporation.
+ *
+ * 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.
+ */
+
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+#include <linux/kernel.h>
+#else
+#include <asm/types.h>
+#endif
+#include <asm/asm-const.h>
+
+/*
+ * On regular PPC32 page size is 4K (but we support 4K/16K/64K/256K pages
+ * on PPC44x). For PPC64 we support either 4K or 64K software
+ * page size. When using 64K pages however, whether we are really supporting
+ * 64K pages in HW or not is irrelevant to those definitions.
+ */
+#if defined(CONFIG_PPC_256K_PAGES)
+#define PAGE_SHIFT		18
+#elif defined(CONFIG_PPC_64K_PAGES)
+#define PAGE_SHIFT		16
+#elif defined(CONFIG_PPC_16K_PAGES)
+#define PAGE_SHIFT		14
+#else
+#define PAGE_SHIFT		12
+#endif
+
+#define PAGE_SIZE		(ASM_CONST(1) << PAGE_SHIFT)
+
+#ifndef __ASSEMBLY__
+#ifdef CONFIG_HUGETLB_PAGE
+extern bool hugetlb_disabled;
+extern unsigned int HPAGE_SHIFT;
+#else
+#define HPAGE_SHIFT PAGE_SHIFT
+#endif
+#define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
+#define HPAGE_MASK		(~(HPAGE_SIZE - 1))
+#define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
+#define HUGE_MAX_HSTATE		(MMU_PAGE_COUNT-1)
+#endif
+
+/*
+ * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we
+ * assign PAGE_MASK to a larger type it gets extended the way we want
+ * (i.e. with 1s in the high bits)
+ */
+#define PAGE_MASK      (~((1 << PAGE_SHIFT) - 1))
+
+/*
+ * KERNELBASE is the virtual address of the start of the kernel, it's often
+ * the same as PAGE_OFFSET, but _might not be_.
+ *
+ * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET.
+ *
+ * PAGE_OFFSET is the virtual address of the start of lowmem.
+ *
+ * PHYSICAL_START is the physical address of the start of the kernel.
+ *
+ * MEMORY_START is the physical address of the start of lowmem.
+ *
+ * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on
+ * ppc32 and based on how they are set we determine MEMORY_START.
+ *
+ * For the linear mapping the following equation should be true:
+ * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START
+ *
+ * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START
+ *
+ * There are two ways to determine a physical address from a virtual one:
+ * va = pa + PAGE_OFFSET - MEMORY_START
+ * va = pa + KERNELBASE - PHYSICAL_START
+ *
+ * If you want to know something's offset from the start of the kernel you
+ * should subtract KERNELBASE.
+ *
+ * If you want to test if something's a kernel address, use is_kernel_addr().
+ */
+
+#define KERNELBASE      ASM_CONST(CONFIG_KERNEL_START)
+#define PAGE_OFFSET	ASM_CONST(CONFIG_PAGE_OFFSET)
+#define LOAD_OFFSET	ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START))
+
+#if defined(CONFIG_NONSTATIC_KERNEL)
+#ifndef __ASSEMBLY__
+
+extern phys_addr_t memstart_addr;
+extern phys_addr_t kernstart_addr;
+
+#if defined(CONFIG_RELOCATABLE) && defined(CONFIG_PPC32)
+extern long long virt_phys_offset;
+#endif
+
+#endif /* __ASSEMBLY__ */
+#define PHYSICAL_START	kernstart_addr
+
+#else	/* !CONFIG_NONSTATIC_KERNEL */
+#define PHYSICAL_START	ASM_CONST(CONFIG_PHYSICAL_START)
+#endif
+
+/* See Description below for VIRT_PHYS_OFFSET */
+#if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
+#ifdef CONFIG_RELOCATABLE
+#define VIRT_PHYS_OFFSET virt_phys_offset
+#else
+#define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START)
+#endif
+#endif
+
+#ifdef CONFIG_PPC64
+#define MEMORY_START	0UL
+#elif defined(CONFIG_NONSTATIC_KERNEL)
+#define MEMORY_START	memstart_addr
+#else
+#define MEMORY_START	(PHYSICAL_START + PAGE_OFFSET - KERNELBASE)
+#endif
+
+#ifdef CONFIG_FLATMEM
+#define ARCH_PFN_OFFSET		((unsigned long)(MEMORY_START >> PAGE_SHIFT))
+#ifndef __ASSEMBLY__
+extern unsigned long max_mapnr;
+static inline bool pfn_valid(unsigned long pfn)
+{
+	unsigned long min_pfn = ARCH_PFN_OFFSET;
+
+	return pfn >= min_pfn && pfn < max_mapnr;
+}
+#endif
+#endif
+
+#define virt_to_pfn(kaddr)	(__pa(kaddr) >> PAGE_SHIFT)
+#define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
+#define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
+
+#ifdef CONFIG_PPC_BOOK3S_64
+/*
+ * On hash the vmalloc and other regions alias to the kernel region when passed
+ * through __pa(), which virt_to_pfn() uses. That means virt_addr_valid() can
+ * return true for some vmalloc addresses, which is incorrect. So explicitly
+ * check that the address is in the kernel region.
+ */
+#define virt_addr_valid(kaddr) (REGION_ID(kaddr) == KERNEL_REGION_ID && \
+				pfn_valid(virt_to_pfn(kaddr)))
+#else
+#define virt_addr_valid(kaddr)	pfn_valid(virt_to_pfn(kaddr))
+#endif
+
+/*
+ * On Book-E parts we need __va to parse the device tree and we can't
+ * determine MEMORY_START until then.  However we can determine PHYSICAL_START
+ * from information at hand (program counter, TLB lookup).
+ *
+ * On BookE with RELOCATABLE && PPC32
+ *
+ *   With RELOCATABLE && PPC32,  we support loading the kernel at any physical
+ *   address without any restriction on the page alignment.
+ *
+ *   We find the runtime address of _stext and relocate ourselves based on 
+ *   the following calculation:
+ *
+ *  	  virtual_base = ALIGN_DOWN(KERNELBASE,256M) +
+ *  				MODULO(_stext.run,256M)
+ *   and create the following mapping:
+ *
+ * 	  ALIGN_DOWN(_stext.run,256M) => ALIGN_DOWN(KERNELBASE,256M)
+ *
+ *   When we process relocations, we cannot depend on the
+ *   existing equation for the __va()/__pa() translations:
+ *
+ * 	   __va(x) = (x)  - PHYSICAL_START + KERNELBASE
+ *
+ *   Where:
+ *   	 PHYSICAL_START = kernstart_addr = Physical address of _stext
+ *  	 KERNELBASE = Compiled virtual address of _stext.
+ *
+ *   This formula holds true iff, kernel load address is TLB page aligned.
+ *
+ *   In our case, we need to also account for the shift in the kernel Virtual 
+ *   address.
+ *
+ *   E.g.,
+ *
+ *   Let the kernel be loaded at 64MB and KERNELBASE be 0xc0000000 (same as PAGE_OFFSET).
+ *   In this case, we would be mapping 0 to 0xc0000000, and kernstart_addr = 64M
+ *
+ *   Now __va(1MB) = (0x100000) - (0x4000000) + 0xc0000000
+ *                 = 0xbc100000 , which is wrong.
+ *
+ *   Rather, it should be : 0xc0000000 + 0x100000 = 0xc0100000
+ *      	according to our mapping.
+ *
+ *   Hence we use the following formula to get the translations right:
+ *
+ * 	  __va(x) = (x) - [ PHYSICAL_START - Effective KERNELBASE ]
+ *
+ * 	  Where :
+ * 		PHYSICAL_START = dynamic load address.(kernstart_addr variable)
+ * 		Effective KERNELBASE = virtual_base =
+ * 				     = ALIGN_DOWN(KERNELBASE,256M) +
+ * 						MODULO(PHYSICAL_START,256M)
+ *
+ * 	To make the cost of __va() / __pa() more light weight, we introduce
+ * 	a new variable virt_phys_offset, which will hold :
+ *
+ * 	virt_phys_offset = Effective KERNELBASE - PHYSICAL_START
+ * 			 = ALIGN_DOWN(KERNELBASE,256M) - 
+ * 			 	ALIGN_DOWN(PHYSICALSTART,256M)
+ *
+ * 	Hence :
+ *
+ * 	__va(x) = x - PHYSICAL_START + Effective KERNELBASE
+ * 		= x + virt_phys_offset
+ *
+ * 		and
+ * 	__pa(x) = x + PHYSICAL_START - Effective KERNELBASE
+ * 		= x - virt_phys_offset
+ * 		
+ * On non-Book-E PPC64 PAGE_OFFSET and MEMORY_START are constants so use
+ * the other definitions for __va & __pa.
+ */
+#if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
+#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + VIRT_PHYS_OFFSET))
+#define __pa(x) ((unsigned long)(x) - VIRT_PHYS_OFFSET)
+#else
+#ifdef CONFIG_PPC64
+/*
+ * gcc miscompiles (unsigned long)(&static_var) - PAGE_OFFSET
+ * with -mcmodel=medium, so we use & and | instead of - and + on 64-bit.
+ */
+#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET))
+#define __pa(x) ((unsigned long)(x) & 0x0fffffffffffffffUL)
+
+#else /* 32-bit, non book E */
+#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START))
+#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START)
+#endif
+#endif
+
+/*
+ * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI,
+ * and needs to be executable.  This means the whole heap ends
+ * up being executable.
+ */
+#define VM_DATA_DEFAULT_FLAGS32 \
+	(((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) | \
+				 VM_READ | VM_WRITE | \
+				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#define VM_DATA_DEFAULT_FLAGS64	(VM_READ | VM_WRITE | \
+				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#ifdef __powerpc64__
+#include <asm/page_64.h>
+#else
+#include <asm/page_32.h>
+#endif
+
+/* align addr on a size boundary - adjust address up/down if needed */
+#define _ALIGN_UP(addr, size)   __ALIGN_KERNEL(addr, size)
+#define _ALIGN_DOWN(addr, size)	((addr)&(~((typeof(addr))(size)-1)))
+
+/* align addr on a size boundary - adjust address up if needed */
+#define _ALIGN(addr,size)     _ALIGN_UP(addr,size)
+
+/*
+ * Don't compare things with KERNELBASE or PAGE_OFFSET to test for
+ * "kernelness", use is_kernel_addr() - it should do what you want.
+ */
+#ifdef CONFIG_PPC_BOOK3E_64
+#define is_kernel_addr(x)	((x) >= 0x8000000000000000ul)
+#else
+#define is_kernel_addr(x)	((x) >= PAGE_OFFSET)
+#endif
+
+#ifndef CONFIG_PPC_BOOK3S_64
+/*
+ * Use the top bit of the higher-level page table entries to indicate whether
+ * the entries we point to contain hugepages.  This works because we know that
+ * the page tables live in kernel space.  If we ever decide to support having
+ * page tables at arbitrary addresses, this breaks and will have to change.
+ */
+#ifdef CONFIG_PPC64
+#define PD_HUGE 0x8000000000000000
+#else
+#define PD_HUGE 0x80000000
+#endif
+
+#else	/* CONFIG_PPC_BOOK3S_64 */
+/*
+ * Book3S 64 stores real addresses in the hugepd entries to
+ * avoid overlaps with _PAGE_PRESENT and _PAGE_PTE.
+ */
+#define HUGEPD_ADDR_MASK	(0x0ffffffffffffffful & ~HUGEPD_SHIFT_MASK)
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
+/*
+ * Some number of bits at the level of the page table that points to
+ * a hugepte are used to encode the size.  This masks those bits.
+ */
+#define HUGEPD_SHIFT_MASK     0x3f
+
+#ifndef __ASSEMBLY__
+
+#ifdef CONFIG_PPC_BOOK3S_64
+#include <asm/pgtable-be-types.h>
+#else
+#include <asm/pgtable-types.h>
+#endif
+
+
+#ifndef CONFIG_HUGETLB_PAGE
+#define is_hugepd(pdep)		(0)
+#define pgd_huge(pgd)		(0)
+#endif /* CONFIG_HUGETLB_PAGE */
+
+struct page;
+extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg);
+extern void copy_user_page(void *to, void *from, unsigned long vaddr,
+		struct page *p);
+extern int page_is_ram(unsigned long pfn);
+extern int devmem_is_allowed(unsigned long pfn);
+
+#ifdef CONFIG_PPC_SMLPAR
+void arch_free_page(struct page *page, int order);
+#define HAVE_ARCH_FREE_PAGE
+#endif
+
+struct vm_area_struct;
+#ifdef CONFIG_PPC_BOOK3S_64
+/*
+ * For BOOK3s 64 with 4k and 64K linux page size
+ * we want to use pointers, because the page table
+ * actually store pfn
+ */
+typedef pte_t *pgtable_t;
+#else
+#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC64)
+typedef pte_t *pgtable_t;
+#else
+typedef struct page *pgtable_t;
+#endif
+#endif
+
+#include <asm-generic/memory_model.h>
+#endif /* __ASSEMBLY__ */
+#include <asm/slice.h>
+
+#endif /* _ASM_POWERPC_PAGE_H */