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	 58b6fed89a
			
		
	
	
		58b6fed89a
		
	
	
	
	
		
			
			Making virt_to_pfn() a static inline taking a strongly typed (const void *) makes the contract of a passing a pointer of that type to the function explicit and exposes any misuse of the macro virt_to_pfn() acting polymorphic and accepting many types such as (void *), (unitptr_t) or (unsigned long) as arguments without warnings. Move the virt_to_pfn() and related functions below the declaration of __pa() so it compiles. For symmetry do the same with pfn_to_kaddr(). As the file is included right into the linker file, we need to surround the functions with ifndef __ASSEMBLY__ so we don't cause compilation errors. The conversion moreover exposes the fact that pmd_page_vaddr() was returning an unsigned long rather than a const void * as could be expected, so all the sites defining pmd_page_vaddr() had to be augmented as well. Finally the KVM code in book3s_64_mmu_hv.c was passing an unsigned int to virt_to_phys() so fix that up with a cast so the result compiles. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> [mpe: Fixup kfence.h, simplify pfn_to_kaddr() & pmd_page_vaddr()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230809-virt-to-phys-powerpc-v1-1-12e912a7d439@linaro.org
		
			
				
	
	
		
			335 lines
		
	
	
	
		
			9.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			335 lines
		
	
	
	
		
			9.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0-or-later */
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| #ifndef _ASM_POWERPC_PAGE_H
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| #define _ASM_POWERPC_PAGE_H
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| 
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| /*
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|  * Copyright (C) 2001,2005 IBM Corporation.
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|  */
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| 
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| #ifndef __ASSEMBLY__
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| #include <linux/types.h>
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| #include <linux/kernel.h>
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| #include <linux/bug.h>
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| #else
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| #include <asm/types.h>
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| #endif
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| #include <asm/asm-const.h>
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| 
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| /*
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|  * On regular PPC32 page size is 4K (but we support 4K/16K/64K/256K pages
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|  * on PPC44x and 4K/16K on 8xx). For PPC64 we support either 4K or 64K software
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|  * page size. When using 64K pages however, whether we are really supporting
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|  * 64K pages in HW or not is irrelevant to those definitions.
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|  */
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| #define PAGE_SHIFT		CONFIG_PPC_PAGE_SHIFT
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| #define PAGE_SIZE		(ASM_CONST(1) << PAGE_SHIFT)
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| 
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| #ifndef __ASSEMBLY__
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| #ifndef CONFIG_HUGETLB_PAGE
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| #define HPAGE_SHIFT PAGE_SHIFT
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| #elif defined(CONFIG_PPC_BOOK3S_64)
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| extern unsigned int hpage_shift;
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| #define HPAGE_SHIFT hpage_shift
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| #elif defined(CONFIG_PPC_8xx)
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| #define HPAGE_SHIFT		19	/* 512k pages */
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| #elif defined(CONFIG_PPC_E500)
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| #define HPAGE_SHIFT		22	/* 4M pages */
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| #endif
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| #define HPAGE_SIZE		((1UL) << HPAGE_SHIFT)
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| #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
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| #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
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| #define HUGE_MAX_HSTATE		(MMU_PAGE_COUNT-1)
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| #endif
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| 
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| /*
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|  * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we
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|  * assign PAGE_MASK to a larger type it gets extended the way we want
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|  * (i.e. with 1s in the high bits)
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|  */
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| #define PAGE_MASK      (~((1 << PAGE_SHIFT) - 1))
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| 
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| /*
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|  * KERNELBASE is the virtual address of the start of the kernel, it's often
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|  * the same as PAGE_OFFSET, but _might not be_.
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|  *
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|  * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET.
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|  *
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|  * PAGE_OFFSET is the virtual address of the start of lowmem.
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|  *
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|  * PHYSICAL_START is the physical address of the start of the kernel.
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|  *
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|  * MEMORY_START is the physical address of the start of lowmem.
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|  *
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|  * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on
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|  * ppc32 and based on how they are set we determine MEMORY_START.
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|  *
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|  * For the linear mapping the following equation should be true:
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|  * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START
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|  *
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|  * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START
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|  *
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|  * There are two ways to determine a physical address from a virtual one:
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|  * va = pa + PAGE_OFFSET - MEMORY_START
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|  * va = pa + KERNELBASE - PHYSICAL_START
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|  *
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|  * If you want to know something's offset from the start of the kernel you
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|  * should subtract KERNELBASE.
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|  *
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|  * If you want to test if something's a kernel address, use is_kernel_addr().
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|  */
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| 
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| #define KERNELBASE      ASM_CONST(CONFIG_KERNEL_START)
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| #define PAGE_OFFSET	ASM_CONST(CONFIG_PAGE_OFFSET)
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| #define LOAD_OFFSET	ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START))
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| 
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| #if defined(CONFIG_NONSTATIC_KERNEL)
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| #ifndef __ASSEMBLY__
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| 
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| extern phys_addr_t memstart_addr;
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| extern phys_addr_t kernstart_addr;
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| 
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| #if defined(CONFIG_RELOCATABLE) && defined(CONFIG_PPC32)
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| extern long long virt_phys_offset;
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| #endif
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| 
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| #endif /* __ASSEMBLY__ */
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| #define PHYSICAL_START	kernstart_addr
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| 
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| #else	/* !CONFIG_NONSTATIC_KERNEL */
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| #define PHYSICAL_START	ASM_CONST(CONFIG_PHYSICAL_START)
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| #endif
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| 
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| /* See Description below for VIRT_PHYS_OFFSET */
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| #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
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| #ifdef CONFIG_RELOCATABLE
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| #define VIRT_PHYS_OFFSET virt_phys_offset
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| #else
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| #define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START)
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| #endif
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| #endif
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| 
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| #ifdef CONFIG_PPC64
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| #define MEMORY_START	0UL
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| #elif defined(CONFIG_NONSTATIC_KERNEL)
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| #define MEMORY_START	memstart_addr
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| #else
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| #define MEMORY_START	(PHYSICAL_START + PAGE_OFFSET - KERNELBASE)
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| #endif
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| 
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| #ifdef CONFIG_FLATMEM
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| #define ARCH_PFN_OFFSET		((unsigned long)(MEMORY_START >> PAGE_SHIFT))
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| #endif
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| 
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| /*
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|  * On Book-E parts we need __va to parse the device tree and we can't
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|  * determine MEMORY_START until then.  However we can determine PHYSICAL_START
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|  * from information at hand (program counter, TLB lookup).
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|  *
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|  * On BookE with RELOCATABLE && PPC32
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|  *
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|  *   With RELOCATABLE && PPC32,  we support loading the kernel at any physical
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|  *   address without any restriction on the page alignment.
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|  *
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|  *   We find the runtime address of _stext and relocate ourselves based on 
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|  *   the following calculation:
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|  *
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|  *  	  virtual_base = ALIGN_DOWN(KERNELBASE,256M) +
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|  *  				MODULO(_stext.run,256M)
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|  *   and create the following mapping:
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|  *
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|  * 	  ALIGN_DOWN(_stext.run,256M) => ALIGN_DOWN(KERNELBASE,256M)
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|  *
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|  *   When we process relocations, we cannot depend on the
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|  *   existing equation for the __va()/__pa() translations:
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|  *
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|  * 	   __va(x) = (x)  - PHYSICAL_START + KERNELBASE
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|  *
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|  *   Where:
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|  *   	 PHYSICAL_START = kernstart_addr = Physical address of _stext
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|  *  	 KERNELBASE = Compiled virtual address of _stext.
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|  *
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|  *   This formula holds true iff, kernel load address is TLB page aligned.
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|  *
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|  *   In our case, we need to also account for the shift in the kernel Virtual 
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|  *   address.
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|  *
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|  *   E.g.,
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|  *
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|  *   Let the kernel be loaded at 64MB and KERNELBASE be 0xc0000000 (same as PAGE_OFFSET).
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|  *   In this case, we would be mapping 0 to 0xc0000000, and kernstart_addr = 64M
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|  *
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|  *   Now __va(1MB) = (0x100000) - (0x4000000) + 0xc0000000
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|  *                 = 0xbc100000 , which is wrong.
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|  *
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|  *   Rather, it should be : 0xc0000000 + 0x100000 = 0xc0100000
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|  *      	according to our mapping.
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|  *
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|  *   Hence we use the following formula to get the translations right:
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|  *
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|  * 	  __va(x) = (x) - [ PHYSICAL_START - Effective KERNELBASE ]
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|  *
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|  * 	  Where :
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|  * 		PHYSICAL_START = dynamic load address.(kernstart_addr variable)
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|  * 		Effective KERNELBASE = virtual_base =
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|  * 				     = ALIGN_DOWN(KERNELBASE,256M) +
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|  * 						MODULO(PHYSICAL_START,256M)
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|  *
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|  * 	To make the cost of __va() / __pa() more light weight, we introduce
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|  * 	a new variable virt_phys_offset, which will hold :
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|  *
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|  * 	virt_phys_offset = Effective KERNELBASE - PHYSICAL_START
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|  * 			 = ALIGN_DOWN(KERNELBASE,256M) - 
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|  * 			 	ALIGN_DOWN(PHYSICALSTART,256M)
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|  *
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|  * 	Hence :
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|  *
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|  * 	__va(x) = x - PHYSICAL_START + Effective KERNELBASE
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|  * 		= x + virt_phys_offset
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|  *
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|  * 		and
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|  * 	__pa(x) = x + PHYSICAL_START - Effective KERNELBASE
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|  * 		= x - virt_phys_offset
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|  * 		
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|  * On non-Book-E PPC64 PAGE_OFFSET and MEMORY_START are constants so use
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|  * the other definitions for __va & __pa.
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|  */
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| #if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
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| #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + VIRT_PHYS_OFFSET))
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| #define __pa(x) ((phys_addr_t)(unsigned long)(x) - VIRT_PHYS_OFFSET)
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| #else
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| #ifdef CONFIG_PPC64
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| 
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| #define VIRTUAL_WARN_ON(x)	WARN_ON(IS_ENABLED(CONFIG_DEBUG_VIRTUAL) && (x))
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| 
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| /*
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|  * gcc miscompiles (unsigned long)(&static_var) - PAGE_OFFSET
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|  * with -mcmodel=medium, so we use & and | instead of - and + on 64-bit.
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|  * This also results in better code generation.
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|  */
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| #define __va(x)								\
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| ({									\
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| 	VIRTUAL_WARN_ON((unsigned long)(x) >= PAGE_OFFSET);		\
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| 	(void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET);	\
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| })
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| 
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| #define __pa(x)								\
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| ({									\
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| 	VIRTUAL_WARN_ON((unsigned long)(x) < PAGE_OFFSET);		\
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| 	(unsigned long)(x) & 0x0fffffffffffffffUL;			\
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| })
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| 
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| #else /* 32-bit, non book E */
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| #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START))
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| #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START)
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| #endif
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| #endif
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| 
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| #ifndef __ASSEMBLY__
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| static inline unsigned long virt_to_pfn(const void *kaddr)
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| {
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| 	return __pa(kaddr) >> PAGE_SHIFT;
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| }
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| 
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| static inline const void *pfn_to_kaddr(unsigned long pfn)
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| {
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| 	return __va(pfn << PAGE_SHIFT);
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| }
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| #endif
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| 
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| #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
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| #define virt_addr_valid(vaddr)	({					\
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| 	unsigned long _addr = (unsigned long)vaddr;			\
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| 	_addr >= PAGE_OFFSET && _addr < (unsigned long)high_memory &&	\
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| 	pfn_valid(virt_to_pfn((void *)_addr));				\
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| })
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| 
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| /*
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|  * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI,
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|  * and needs to be executable.  This means the whole heap ends
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|  * up being executable.
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|  */
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| #define VM_DATA_DEFAULT_FLAGS32	VM_DATA_FLAGS_TSK_EXEC
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| #define VM_DATA_DEFAULT_FLAGS64	VM_DATA_FLAGS_NON_EXEC
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| 
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| #ifdef __powerpc64__
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| #include <asm/page_64.h>
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| #else
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| #include <asm/page_32.h>
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| #endif
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| 
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| /*
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|  * Don't compare things with KERNELBASE or PAGE_OFFSET to test for
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|  * "kernelness", use is_kernel_addr() - it should do what you want.
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|  */
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| #ifdef CONFIG_PPC_BOOK3E_64
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| #define is_kernel_addr(x)	((x) >= 0x8000000000000000ul)
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| #elif defined(CONFIG_PPC_BOOK3S_64)
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| #define is_kernel_addr(x)	((x) >= PAGE_OFFSET)
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| #else
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| #define is_kernel_addr(x)	((x) >= TASK_SIZE)
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| #endif
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| 
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| #ifndef CONFIG_PPC_BOOK3S_64
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| /*
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|  * Use the top bit of the higher-level page table entries to indicate whether
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|  * the entries we point to contain hugepages.  This works because we know that
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|  * the page tables live in kernel space.  If we ever decide to support having
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|  * page tables at arbitrary addresses, this breaks and will have to change.
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|  */
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| #ifdef CONFIG_PPC64
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| #define PD_HUGE 0x8000000000000000UL
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| #else
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| #define PD_HUGE 0x80000000
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| #endif
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| 
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| #else	/* CONFIG_PPC_BOOK3S_64 */
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| /*
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|  * Book3S 64 stores real addresses in the hugepd entries to
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|  * avoid overlaps with _PAGE_PRESENT and _PAGE_PTE.
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|  */
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| #define HUGEPD_ADDR_MASK	(0x0ffffffffffffffful & ~HUGEPD_SHIFT_MASK)
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| #endif /* CONFIG_PPC_BOOK3S_64 */
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| 
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| /*
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|  * Some number of bits at the level of the page table that points to
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|  * a hugepte are used to encode the size.  This masks those bits.
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|  * On 8xx, HW assistance requires 4k alignment for the hugepte.
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|  */
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| #ifdef CONFIG_PPC_8xx
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| #define HUGEPD_SHIFT_MASK     0xfff
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| #else
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| #define HUGEPD_SHIFT_MASK     0x3f
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| #endif
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| 
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| #ifndef __ASSEMBLY__
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| 
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| #ifdef CONFIG_PPC_BOOK3S_64
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| #include <asm/pgtable-be-types.h>
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| #else
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| #include <asm/pgtable-types.h>
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| #endif
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| 
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| struct page;
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| extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg);
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| extern void copy_user_page(void *to, void *from, unsigned long vaddr,
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| 		struct page *p);
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| extern int devmem_is_allowed(unsigned long pfn);
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| 
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| #ifdef CONFIG_PPC_SMLPAR
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| void arch_free_page(struct page *page, int order);
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| #define HAVE_ARCH_FREE_PAGE
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| #endif
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| 
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| struct vm_area_struct;
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| 
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| extern unsigned long kernstart_virt_addr;
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| 
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| static inline unsigned long kaslr_offset(void)
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| {
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| 	return kernstart_virt_addr - KERNELBASE;
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| }
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| 
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| #include <asm-generic/memory_model.h>
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| #endif /* __ASSEMBLY__ */
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| 
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| #endif /* _ASM_POWERPC_PAGE_H */
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