C PROGRAMMING

The Linux kernel uses the memory descriptor data structure to represent a process's address space. The mem- ory descriptor struct mm_struct is defined in and included in a process's task_struct. In mm_struct the mm_users field is the number of processes using this address space and the mm_count field is the reference count for this mm_struct. The vm_area_struct describes a single memory area over a con- tiguous interval in an address space. All the virtual memory areas together form a process's virtual address space. To calculate the size of a virtual address space, one only needs to sum the sizes of individual virtual memory areas (VMA). The VMAs in a process can be accessed in two ways. mmap in mm_struct points to a sorted linked list of all VMAs of a process. mm_rb points to a red-black tree of VMAs, which can be used to search for a given VMA. You can verify your result using pmap. The Linux kernel uses the memory descriptor data structure to represent a process's address space. The mem- ory descriptor struct mm_struct is defined in and included in a process's task_struct. In mm_struct the mm_users field is the number of processes using this address space and the mm_count field is the reference count for this mm_struct. The vm_area_struct describes a single memory area over a con- tiguous interval in an address space. All the virtual memory areas together form a process's virtual address space. To calculate the size of a virtual address space, one only needs to sum the sizes of individual virtual memory areas (VMA). The VMAs in a process can be accessed in two ways. mmap in mm_struct points to a sorted linked list of all VMAs of a process. mm_rb points to a red-black tree of VMAs, which can be used to search for a given VMA. You can verify your result using pmap