cregit-Linux how code gets into the kernel

Release 4.9 arch/arm/include/asm/memory.h

/*
 *  arch/arm/include/asm/memory.h
 *
 *  Copyright (C) 2000-2002 Russell King
 *  modification for nommu, Hyok S. Choi, 2004
 *
 * 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.
 *
 *  Note: this file should not be included by non-asm/.h files
 */
#ifndef __ASM_ARM_MEMORY_H

#define __ASM_ARM_MEMORY_H

#include <linux/compiler.h>
#include <linux/const.h>
#include <linux/types.h>
#include <linux/sizes.h>

#ifdef CONFIG_NEED_MACH_MEMORY_H
#include <mach/memory.h>
#endif

/*
 * Allow for constants defined here to be used from assembly code
 * by prepending the UL suffix only with actual C code compilation.
 */

#define UL(x) _AC(x, UL)

/* PAGE_OFFSET - the virtual address of the start of the kernel image */

#define PAGE_OFFSET		UL(CONFIG_PAGE_OFFSET)

#ifdef CONFIG_MMU

/*
 * TASK_SIZE - the maximum size of a user space task.
 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
 */

#define TASK_SIZE		(UL(CONFIG_PAGE_OFFSET) - UL(SZ_16M))

#define TASK_UNMAPPED_BASE	ALIGN(TASK_SIZE / 3, SZ_16M)

/*
 * The maximum size of a 26-bit user space task.
 */

#define TASK_SIZE_26		(UL(1) << 26)

/*
 * The module space lives between the addresses given by TASK_SIZE
 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
 */
#ifndef CONFIG_THUMB2_KERNEL

#define MODULES_VADDR		(PAGE_OFFSET - SZ_16M)
#else
/* smaller range for Thumb-2 symbols relocation (2^24)*/

#define MODULES_VADDR		(PAGE_OFFSET - SZ_8M)
#endif

#if TASK_SIZE > MODULES_VADDR
#error Top of user space clashes with start of module space
#endif

/*
 * The highmem pkmap virtual space shares the end of the module area.
 */
#ifdef CONFIG_HIGHMEM

#define MODULES_END		(PAGE_OFFSET - PMD_SIZE)
#else

#define MODULES_END		(PAGE_OFFSET)
#endif

/*
 * The XIP kernel gets mapped at the bottom of the module vm area.
 * Since we use sections to map it, this macro replaces the physical address
 * with its virtual address while keeping offset from the base section.
 */

#define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))

#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
/*
 * Allow 16MB-aligned ioremap pages
 */

#define IOREMAP_MAX_ORDER	24
#endif

#else /* CONFIG_MMU */

/*
 * The limitation of user task size can grow up to the end of free ram region.
 * It is difficult to define and perhaps will never meet the original meaning
 * of this define that was meant to.
 * Fortunately, there is no reference for this in noMMU mode, for now.
 */

#define TASK_SIZE		UL(0xffffffff)

#ifndef TASK_UNMAPPED_BASE

#define TASK_UNMAPPED_BASE	UL(0x00000000)
#endif

#ifndef END_MEM

#define END_MEM     		(UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
#endif

/*
 * The module can be at any place in ram in nommu mode.
 */

#define MODULES_END		(END_MEM)

#define MODULES_VADDR		PAGE_OFFSET


#define XIP_VIRT_ADDR(physaddr)  (physaddr)

#endif /* !CONFIG_MMU */

/*
 * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
 * locations
 */
#ifdef CONFIG_HAVE_TCM

#define ITCM_OFFSET	UL(0xfffe0000)

#define DTCM_OFFSET	UL(0xfffe8000)
#endif

/*
 * Convert a page to/from a physical address
 */

#define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))

#define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))

/*
 * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
 * memory.  This is used for XIP and NoMMU kernels, and on platforms that don't
 * have CONFIG_ARM_PATCH_PHYS_VIRT. Assembly code must always use
 * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
 */

#define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)

#ifdef CONFIG_XIP_KERNEL
/*
 * When referencing data in RAM from the XIP region in a relative manner
 * with the MMU off, we need the relative offset between the two physical
 * addresses.  The macro below achieves this, which is:
 *    __pa(v_data) - __xip_pa(v_text)
 */

#define PHYS_RELATIVE(v_data, v_text) \
	(((v_data) - PAGE_OFFSET + PLAT_PHYS_OFFSET) - \
         ((v_text) - XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR) + \
          CONFIG_XIP_PHYS_ADDR))
#else

#define PHYS_RELATIVE(v_data, v_text) ((v_data) - (v_text))
#endif

#ifndef __ASSEMBLY__

/*
 * Physical vs virtual RAM address space conversion.  These are
 * private definitions which should NOT be used outside memory.h
 * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 *
 * PFNs are used to describe any physical page; this means
 * PFN 0 == physical address 0.
 */

#if defined(CONFIG_ARM_PATCH_PHYS_VIRT)

/*
 * Constants used to force the right instruction encodings and shifts
 * so that all we need to do is modify the 8-bit constant field.
 */

#define __PV_BITS_31_24	0x81000000

#define __PV_BITS_7_0	0x81

extern unsigned long __pv_phys_pfn_offset;
extern u64 __pv_offset;
extern void fixup_pv_table(const void *, unsigned long);
extern const void *__pv_table_begin, *__pv_table_end;


#define PHYS_OFFSET	((phys_addr_t)__pv_phys_pfn_offset << PAGE_SHIFT)

#define PHYS_PFN_OFFSET	(__pv_phys_pfn_offset)


#define __pv_stub(from,to,instr,type)			\
	__asm__("@ __pv_stub\n"                         \
        "1:     " instr "       %0, %1, %2\n"           \
        "       .pushsection .pv_table,\"a\"\n"         \
        "       .long   1b\n"                           \
        "       .popsection\n"                          \
        : "=r" (to)                                     \
        : "r" (from), "I" (type))


#define __pv_stub_mov_hi(t)				\
	__asm__ volatile("@ __pv_stub_mov\n"            \
        "1:     mov     %R0, %1\n"                      \
        "       .pushsection .pv_table,\"a\"\n"         \
        "       .long   1b\n"                           \
        "       .popsection\n"                          \
        : "=r" (t)                                      \
        : "I" (__PV_BITS_7_0))


#define __pv_add_carry_stub(x, y)			\
	__asm__ volatile("@ __pv_add_carry_stub\n"      \
        "1:     adds    %Q0, %1, %2\n"                  \
        "       adc     %R0, %R0, #0\n"                 \
        "       .pushsection .pv_table,\"a\"\n"         \
        "       .long   1b\n"                           \
        "       .popsection\n"                          \
        : "+r" (y)                                      \
        : "r" (x), "I" (__PV_BITS_31_24)                \
        : "cc")


static inline phys_addr_t __virt_to_phys(unsigned long x) { phys_addr_t t; if (sizeof(phys_addr_t) == 4) { __pv_stub(x, t, "add", __PV_BITS_31_24); } else { __pv_stub_mov_hi(t); __pv_add_carry_stub(x, t); } return t; }

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russell kingrussell king2648.15%250.00%
santosh shilimkarsantosh shilimkar11.85%125.00%
Total54100.00%4100.00%


static inline unsigned long __phys_to_virt(phys_addr_t x) { unsigned long t; /* * 'unsigned long' cast discard upper word when * phys_addr_t is 64 bit, and makes sure that inline * assembler expression receives 32 bit argument * in place where 'r' 32 bit operand is expected. */ __pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24); return t; }

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russell kingrussell king2882.35%250.00%
victor kamenskyvictor kamensky514.71%125.00%
santosh shilimkarsantosh shilimkar12.94%125.00%
Total34100.00%4100.00%

#else #define PHYS_OFFSET PLAT_PHYS_OFFSET #define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
static inline phys_addr_t __virt_to_phys(unsigned long x) { return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET; }

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santosh shilimkarsantosh shilimkar1780.95%150.00%
russell kingrussell king419.05%150.00%
Total21100.00%2100.00%


static inline unsigned long __phys_to_virt(phys_addr_t x) { return x - PHYS_OFFSET + PAGE_OFFSET; }

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santosh shilimkarsantosh shilimkar1477.78%150.00%
russell kingrussell king422.22%150.00%
Total18100.00%2100.00%

#endif #define virt_to_pfn(kaddr) \ ((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \ PHYS_PFN_OFFSET) /* * These are *only* valid on the kernel direct mapped RAM memory. * Note: Drivers should NOT use these. They are the wrong * translation for translating DMA addresses. Use the driver * DMA support - see dma-mapping.h. */ #define virt_to_phys virt_to_phys
static inline phys_addr_t virt_to_phys(const volatile void *x) { return __virt_to_phys((unsigned long)(x)); }

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will deaconwill deacon14.00%125.00%
Total25100.00%4100.00%

#define phys_to_virt phys_to_virt
static inline void *phys_to_virt(phys_addr_t x) { return (void *)__phys_to_virt(x); }

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will deaconwill deacon14.76%133.33%
Total21100.00%3100.00%

/* * Drivers should NOT use these either. */ #define __pa(x) __virt_to_phys((unsigned long)(x)) #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x))) #define pfn_to_kaddr(pfn) __va((phys_addr_t)(pfn) << PAGE_SHIFT) extern long long arch_phys_to_idmap_offset; /* * These are for systems that have a hardware interconnect supported alias * of physical memory for idmap purposes. Most cases should leave these * untouched. Note: this can only return addresses less than 4GiB. */
static inline bool arm_has_idmap_alias(void) { return IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset != 0; }

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#define IDMAP_INVALID_ADDR ((u32)~0)
static inline unsigned long phys_to_idmap(phys_addr_t addr) { if (IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset) { addr += arch_phys_to_idmap_offset; if (addr > (u32)~0) addr = IDMAP_INVALID_ADDR; } return addr; }

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russell kingrussell king3479.07%375.00%
santosh shilimkarsantosh shilimkar920.93%125.00%
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static inline phys_addr_t idmap_to_phys(unsigned long idmap) { phys_addr_t addr = idmap; if (IS_ENABLED(CONFIG_MMU) && arch_phys_to_idmap_offset) addr -= arch_phys_to_idmap_offset; return addr; }

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russell kingrussell king2990.62%150.00%
santosh shilimkarsantosh shilimkar39.38%150.00%
Total32100.00%2100.00%


static inline unsigned long __virt_to_idmap(unsigned long x) { return phys_to_idmap(__virt_to_phys(x)); }

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russell kingrussell king1466.67%150.00%
santosh shilimkarsantosh shilimkar733.33%150.00%
Total21100.00%2100.00%

#define virt_to_idmap(x) __virt_to_idmap((unsigned long)(x)) /* * Virtual <-> DMA view memory address translations * Again, these are *only* valid on the kernel direct mapped RAM * memory. Use of these is *deprecated* (and that doesn't mean * use the __ prefixed forms instead.) See dma-mapping.h. */ #ifndef __virt_to_bus #define __virt_to_bus __virt_to_phys #define __bus_to_virt __phys_to_virt #define __pfn_to_bus(x) __pfn_to_phys(x) #define __bus_to_pfn(x) __phys_to_pfn(x) #endif /* * Conversion between a struct page and a physical address. * * page_to_pfn(page) convert a struct page * to a PFN number * pfn_to_page(pfn) convert a _valid_ PFN number to struct page * * * virt_to_page(k) convert a _valid_ virtual address to struct page * * virt_addr_valid(k) indicates whether a virtual address is valid */ #define ARCH_PFN_OFFSET PHYS_PFN_OFFSET #define virt_to_page(kaddr) pfn_to_page(virt_to_pfn(kaddr)) #define virt_addr_valid(kaddr) (((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \ && pfn_valid(virt_to_pfn(kaddr))) #endif #include <asm-generic/memory_model.h> #endif

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russell kingrussell king38452.39%2441.38%
r sricharanr sricharan729.82%11.72%
santosh shilimkarsantosh shilimkar608.19%23.45%
nicolas pitrenicolas pitre557.50%712.07%
pre-gitpre-git486.55%11.72%
lennert buytenheklennert buytenhek172.32%23.45%
sergey dyaslysergey dyasly152.05%11.72%
linus walleijlinus walleij141.91%11.72%
catalin marinascatalin marinas131.77%23.45%
will deaconwill deacon101.36%35.17%
uwe kleine-koeniguwe kleine-koenig91.23%35.17%
thierry redingthierry reding81.09%11.72%
hiroki kaminagahiroki kaminaga60.82%11.72%
victor kamenskyvictor kamensky50.68%11.72%
kamezawa hiroyukikamezawa hiroyuki40.55%11.72%
linus torvaldslinus torvalds40.55%11.72%
al viroal viro30.41%11.72%
kevin hilmankevin hilman20.27%11.72%
vitaly andrianovvitaly andrianov10.14%11.72%
alessandro rubinialessandro rubini10.14%11.72%
andreas fenkartandreas fenkart10.14%11.72%
jiang liujiang liu10.14%11.72%
Total733100.00%58100.00%