init-mm.c (1681B)
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 11#include <linux/atomic.h> 12#include <linux/user_namespace.h> 13#include <linux/ioasid.h> 14#include <asm/mmu.h> 15 16#ifndef INIT_MM_CONTEXT 17#define INIT_MM_CONTEXT(name) 18#endif 19 20/* 21 * For dynamically allocated mm_structs, there is a dynamically sized cpumask 22 * at the end of the structure, the size of which depends on the maximum CPU 23 * number the system can see. That way we allocate only as much memory for 24 * mm_cpumask() as needed for the hundreds, or thousands of processes that 25 * a system typically runs. 26 * 27 * Since there is only one init_mm in the entire system, keep it simple 28 * and size this cpu_bitmask to NR_CPUS. 29 */ 30struct mm_struct init_mm = { 31 .mm_rb = RB_ROOT, 32 .pgd = swapper_pg_dir, 33 .mm_users = ATOMIC_INIT(2), 34 .mm_count = ATOMIC_INIT(1), 35 .write_protect_seq = SEQCNT_ZERO(init_mm.write_protect_seq), 36 MMAP_LOCK_INITIALIZER(init_mm) 37 .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock), 38 .arg_lock = __SPIN_LOCK_UNLOCKED(init_mm.arg_lock), 39 .mmlist = LIST_HEAD_INIT(init_mm.mmlist), 40 .user_ns = &init_user_ns, 41 .cpu_bitmap = CPU_BITS_NONE, 42#ifdef CONFIG_IOMMU_SVA 43 .pasid = INVALID_IOASID, 44#endif 45 INIT_MM_CONTEXT(init_mm) 46}; 47 48void setup_initial_init_mm(void *start_code, void *end_code, 49 void *end_data, void *brk) 50{ 51 init_mm.start_code = (unsigned long)start_code; 52 init_mm.end_code = (unsigned long)end_code; 53 init_mm.end_data = (unsigned long)end_data; 54 init_mm.brk = (unsigned long)brk; 55}