init-mm.c 1.4 KB

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  1. // SPDX-License-Identifier: GPL-2.0
  2. #include <linux/mm_types.h>
  3. #include <linux/rbtree.h>
  4. #include <linux/rwsem.h>
  5. #include <linux/spinlock.h>
  6. #include <linux/list.h>
  7. #include <linux/cpumask.h>
  8. #include <linux/mman.h>
  9. #include <linux/pgtable.h>
  10. #include <linux/atomic.h>
  11. #include <linux/user_namespace.h>
  12. #include <asm/mmu.h>
  13. #ifndef INIT_MM_CONTEXT
  14. #define INIT_MM_CONTEXT(name)
  15. #endif
  16. /*
  17. * For dynamically allocated mm_structs, there is a dynamically sized cpumask
  18. * at the end of the structure, the size of which depends on the maximum CPU
  19. * number the system can see. That way we allocate only as much memory for
  20. * mm_cpumask() as needed for the hundreds, or thousands of processes that
  21. * a system typically runs.
  22. *
  23. * Since there is only one init_mm in the entire system, keep it simple
  24. * and size this cpu_bitmask to NR_CPUS.
  25. */
  26. struct mm_struct init_mm = {
  27. .mm_rb = RB_ROOT,
  28. #ifdef CONFIG_SPECULATIVE_PAGE_FAULT
  29. .mm_rb_lock = __RW_LOCK_UNLOCKED(init_mm.mm_rb_lock),
  30. #endif
  31. .pgd = swapper_pg_dir,
  32. .mm_users = ATOMIC_INIT(2),
  33. .mm_count = ATOMIC_INIT(1),
  34. .write_protect_seq = SEQCNT_ZERO(init_mm.write_protect_seq),
  35. MMAP_LOCK_INITIALIZER(init_mm)
  36. .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock),
  37. .arg_lock = __SPIN_LOCK_UNLOCKED(init_mm.arg_lock),
  38. .mmlist = LIST_HEAD_INIT(init_mm.mmlist),
  39. .user_ns = &init_user_ns,
  40. .cpu_bitmap = CPU_BITS_NONE,
  41. INIT_MM_CONTEXT(init_mm)
  42. };