diff options
Diffstat (limited to 'mm/init-mm.c')
| -rw-r--r-- | mm/init-mm.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/mm/init-mm.c b/mm/init-mm.c new file mode 100644 index 000000000..153162669 --- /dev/null +++ b/mm/init-mm.c @@ -0,0 +1,42 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/mm_types.h> +#include <linux/rbtree.h> +#include <linux/rwsem.h> +#include <linux/spinlock.h> +#include <linux/list.h> +#include <linux/cpumask.h> +#include <linux/mman.h> +#include <linux/pgtable.h> + +#include <linux/atomic.h> +#include <linux/user_namespace.h> +#include <asm/mmu.h> + +#ifndef INIT_MM_CONTEXT +#define INIT_MM_CONTEXT(name) +#endif + +/* + * For dynamically allocated mm_structs, there is a dynamically sized cpumask + * at the end of the structure, the size of which depends on the maximum CPU + * number the system can see. That way we allocate only as much memory for + * mm_cpumask() as needed for the hundreds, or thousands of processes that + * a system typically runs. + * + * Since there is only one init_mm in the entire system, keep it simple + * and size this cpu_bitmask to NR_CPUS. + */ +struct mm_struct init_mm = { + .mm_rb = RB_ROOT, + .pgd = swapper_pg_dir, + .mm_users = ATOMIC_INIT(2), + .mm_count = ATOMIC_INIT(1), + .write_protect_seq = SEQCNT_ZERO(init_mm.write_protect_seq), + MMAP_LOCK_INITIALIZER(init_mm) + .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock), + .arg_lock = __SPIN_LOCK_UNLOCKED(init_mm.arg_lock), + .mmlist = LIST_HEAD_INIT(init_mm.mmlist), + .user_ns = &init_user_ns, + .cpu_bitmap = CPU_BITS_NONE, + INIT_MM_CONTEXT(init_mm) +}; |