inmates/lib/x86/mem.c

   1 /*
   2  * Jailhouse, a Linux-based partitioning hypervisor
   3  *
   4  * Copyright (c) Siemens AG, 2014
   5  *
   6  * Authors:
   7  *  Jan Kiszka <jan.kiszka@siemens.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  */
  12
  13 #include <inmate.h>
  14
  15 #define PG_PRESENT      0x01
  16 #define PG_RW           0x02
  17 #define PG_PS           0x80
  18 #define PG_PCD          0x10
  19
  20 static unsigned long heap_pos = HEAP_BASE;
  21
  22 void *alloc(unsigned long size, unsigned long align)
  23 {
  24         unsigned long base = (heap_pos + align - 1) & ~(align - 1);
  25
  26         heap_pos = base + size;
  27         return (void *)base;
  28 }
  29
  30 void map_range(void *start, unsigned long size, enum map_type map_type)
  31 {
  32         unsigned long pt_addr, *pt_entry, *pt;
  33         unsigned long vaddr = (unsigned long)start;
  34
  35         asm volatile("mov %%cr3,%0" : "=r" (pt_addr));
  36
  37         size += HUGE_PAGE_SIZE - 1;
  38         size &= HUGE_PAGE_MASK;
  39         while (size > 0) {
  40 #ifdef __x86_64__
  41                 pt_addr &= PAGE_MASK;
  42                 pt = (unsigned long *)pt_addr;
  43
  44                 pt_entry = &pt[(vaddr >> 39) & 0x1ff];
  45                 if (*pt_entry & PG_PRESENT) {
  46                         pt = (unsigned long *)(*pt_entry & PAGE_MASK);
  47                 } else {
  48                         pt = alloc(PAGE_SIZE, PAGE_SIZE);
  49                         *pt_entry = (unsigned long)pt | PG_RW | PG_PRESENT;
  50                 }
  51
  52                 pt_entry = &pt[(vaddr >> 30) & 0x1ff];
  53                 if (*pt_entry & PG_PRESENT) {
  54                         pt = (unsigned long *)(*pt_entry & PAGE_MASK);
  55                 } else {
  56                         pt = alloc(PAGE_SIZE, PAGE_SIZE);
  57                         *pt_entry = (unsigned long)pt | PG_RW | PG_PRESENT;
  58                 }
  59
  60                 pt_entry = &pt[(vaddr >> 21) & 0x1ff];
  61                 *pt_entry = (vaddr & HUGE_PAGE_MASK) |
  62                         (map_type == MAP_UNCACHED ? PG_PCD : 0) |
  63                         PG_PS | PG_RW | PG_PRESENT;
  64 #else
  65 #error not yet implemented
  66 #endif
  67                 size -= HUGE_PAGE_SIZE;
  68                 vaddr += HUGE_PAGE_SIZE;
  69         }
  70 }