/*
- buddy_get_pages: get free page from buddy system.
- pool @ physical memory structure reserved in the kernel
- order @ get the (1<<order) continous pages from the buddy system
*
- Hints: Find the corresonding free_list which can allocate 1<<order
- continuous pages and don't forget to split the list node after allocation
*/
struct page *buddy_get_pages(struct phys_mem_pool *pool, u64 order)
该函数所实现的功能是分配一个order等于"传入的参数order"的page。
但是注释中写的是get the (1<<order) continous pages from the buddy system,让人误以为要返回2order个页