Documentation/translations/zh_CN/arch/riscv/vm-layout.rst

   1 .. SPDX-License-Identifier: GPL-2.0
   2 .. include:: ../../disclaimer-zh_CN.rst
   3
   4 :Original: Documentation/arch/riscv/vm-layout.rst
   5
   6 :翻译:
   7
   8  司延腾 Yanteng Si <siyanteng@loongson.cn>
   9         Binbin Zhou <zhoubinbin@loongson.cn>
  10
  11 ============================
  12 RISC-V Linux上的虚拟内存布局
  13 ============================
  14
  15 :作者: Alexandre Ghiti <alex@ghiti.fr>
  16 :日期: 12 February 2021
  17
  18 这份文件描述了RISC-V Linux内核使用的虚拟内存布局。
  19
  20 32位 RISC-V Linux 内核
  21 ======================
  22
  23 RISC-V Linux Kernel SV32
  24 ------------------------
  25
  26 TODO
  27
  28 64位 RISC-V Linux 内核
  29 ======================
  30
  31 RISC-V特权架构文档指出，64位地址 "必须使第63-48位值都等于第47位，否则将发生缺页异常。"：这将虚
  32 拟地址空间分成两半，中间有一个非常大的洞，下半部分是用户空间所在的地方，上半部分是RISC-V Linux
  33 内核所在的地方。
  34
  35 RISC-V Linux Kernel SV39
  36 ------------------------
  37
  38 ::
  39
  40   ========================================================================================================================
  41       开始地址       |   偏移      |     结束地址      |  大小    | 虚拟内存区域描述
  42   ========================================================================================================================
  43                     |            |                  |         |
  44    0000000000000000 |    0       | 0000003fffffffff |  256 GB | 用户空间虚拟内存，每个内存管理器不同
  45   __________________|____________|__________________|_________|___________________________________________________________
  46                     |            |                  |         |
  47    0000004000000000 | +256    GB | ffffffbfffffffff | ~16M TB | ... 巨大的、几乎64位宽的直到内核映射的-256GB地方
  48                     |            |                  |         |     开始偏移的非经典虚拟内存地址空洞。
  49                     |            |                  |         |
  50   __________________|____________|__________________|_________|___________________________________________________________
  51                                                               |
  52                                                               | 内核空间的虚拟内存，在所有进程之间共享:
  53   ____________________________________________________________|___________________________________________________________
  54                     |            |                  |         |
  55    ffffffc6fee00000 | -228    GB | ffffffc6feffffff |    2 MB | fixmap
  56    ffffffc6ff000000 | -228    GB | ffffffc6ffffffff |   16 MB | PCI io
  57    ffffffc700000000 | -228    GB | ffffffc7ffffffff |    4 GB | vmemmap
  58    ffffffc800000000 | -224    GB | ffffffd7ffffffff |   64 GB | vmalloc/ioremap space
  59    ffffffd800000000 | -160    GB | fffffff6ffffffff |  124 GB | 直接映射所有物理内存
  60    fffffff700000000 |  -36    GB | fffffffeffffffff |   32 GB | kasan
  61   __________________|____________|__________________|_________|____________________________________________________________
  62                                                               |
  63                                                               |
  64   ____________________________________________________________|____________________________________________________________
  65                     |            |                  |         |
  66    ffffffff00000000 |   -4    GB | ffffffff7fffffff |    2 GB | modules, BPF
  67    ffffffff80000000 |   -2    GB | ffffffffffffffff |    2 GB | kernel
  68   __________________|____________|__________________|_________|____________________________________________________________
  69
  70
  71 RISC-V Linux Kernel SV48
  72 ------------------------
  73
  74 ::
  75
  76  ========================================================================================================================
  77       开始地址       |   偏移      |     结束地址      |  大小    | 虚拟内存区域描述
  78  ========================================================================================================================
  79                     |            |                  |         |
  80    0000000000000000 |    0       | 00007fffffffffff |  128 TB | 用户空间虚拟内存，每个内存管理器不同
  81   __________________|____________|__________________|_________|___________________________________________________________
  82                     |            |                  |         |
  83    0000800000000000 | +128    TB | ffff7fffffffffff | ~16M TB | ... 巨大的、几乎64位宽的直到内核映射的-128TB地方
  84                     |            |                  |         |     开始偏移的非经典虚拟内存地址空洞。
  85                     |            |                  |         |
  86   __________________|____________|__________________|_________|___________________________________________________________
  87                                                               |
  88                                                               | 内核空间的虚拟内存，在所有进程之间共享:
  89   ____________________________________________________________|___________________________________________________________
  90                     |            |                  |         |
  91    ffff8d7ffee00000 |  -114.5 TB | ffff8d7ffeffffff |    2 MB | fixmap
  92    ffff8d7fff000000 |  -114.5 TB | ffff8d7fffffffff |   16 MB | PCI io
  93    ffff8d8000000000 |  -114.5 TB | ffff8f7fffffffff |    2 TB | vmemmap
  94    ffff8f8000000000 |  -112.5 TB | ffffaf7fffffffff |   32 TB | vmalloc/ioremap space
  95    ffffaf8000000000 |  -80.5  TB | ffffef7fffffffff |   64 TB | 直接映射所有物理内存
  96    ffffef8000000000 |  -16.5  TB | fffffffeffffffff | 16.5 TB | kasan
  97   __________________|____________|__________________|_________|____________________________________________________________
  98                                                               |
  99                                                               | 从此处开始，与39-bit布局相同：
 100   ____________________________________________________________|____________________________________________________________
 101                     |            |                  |         |
 102    ffffffff00000000 |   -4    GB | ffffffff7fffffff |    2 GB | modules, BPF
 103    ffffffff80000000 |   -2    GB | ffffffffffffffff |    2 GB | kernel
 104   __________________|____________|__________________|_________|____________________________________________________________