umovestr: read chunks of memory up to pagesize at a time

* defs.h (get_pagesize): New prototype.
* mem.c (get_pagesize) Make global.
* util.c (PAGMASK): Remove.
(vm_read_mem): New process_vm_readv proxy function.
(umoven, umovestr): Use it.
(umovestr): Read chunks up to pagesize at a time.
3 files changed