munmap
Version
- Linux v5.8.13
Abstract
long sys_munmap(unsigned long addr, size_t len);
Arguments
Return
Definitions
sys_munmap()
- mm/mmap.c
SYSCALL_DEFINE2(munmap, unsigned long, addr, size_t, len)
{
addr = untagged_addr(addr);
profile_munmap(addr);
return __vm_munmap(addr, len, true);
}
__vm_munmap()
- mm/mmap.c
static int __vm_munmap(unsigned long start, size_t len, bool downgrade)
{
int ret;
struct mm_struct *mm = current->mm;
LIST_HEAD(uf);
if (mmap_write_lock_killable(mm))
return -EINTR;
ret = __do_munmap(mm, start, len, &uf, downgrade);
/*
* Returning 1 indicates mmap_lock is downgraded.
* But 1 is not legal return value of vm_munmap() and munmap(), reset
* it to 0 before return.
*/
if (ret == 1) {
mmap_read_unlock(mm);
ret = 0;
} else
mmap_write_unlock(mm);
userfaultfd_unmap_complete(mm, &uf);
return ret;
}
mm/mmap.c の外から呼び出したい場合には vm_munmap() を使用する．
プロトタイプは include/linux/mm.h に宣言されている．
int vm_munmap(unsigned long start, size_t len)
{
return __vm_munmap(start, len, false);
}
EXPORT_SYMBOL(vm_munmap);