Mastering Linux Kernel Development

Process memory descriptor

The kernel maintains all information on process memory segments and the corresponding translation table in a memory descriptor structure, which is of type struct mm_struct. The process descriptor structure task_struct contains a pointer *mm to the memory descriptor for the process. We shall discuss a few important elements of the memory descriptor structure:

struct mm_struct {               struct vm_area_struct *mmap; /* list of VMAs */               struct rb_root mm_rb;               u32 vmacache_seqnum; /* per-thread vmacache */#ifdef CONFIG_MMU             unsigned long (*get_unmapped_area) (struct file *filp, unsigned long addr, unsigned long len,                                                                                                    unsigned long pgoff, unsigned long flags); #endif            unsigned long mmap_base;               /* base of mmap area */ unsigned long mmap_legacy_base; ...