1 /* The kernel call implemented in this file: 2 * m_type: SYS_READBIOS 3 * 4 * The parameters for this kernel call are: 5 * m_lsys_krn_readbios.size number of bytes to copy 6 * m_lsys_krn_readbios.addr absolute address in BIOS area 7 * m_lsys_krn_readbios.buf buffer address in requesting process 8 */ 9 10 #include "kernel/system.h" 11 12 /*===========================================================================* 13 * do_readbios * 14 *===========================================================================*/ 15 int do_readbios(struct proc * caller, message * m_ptr) 16 { 17 struct vir_addr src, dst; 18 size_t len = m_ptr->m_lsys_krn_readbios.size; 19 vir_bytes limit; 20 21 src.offset = m_ptr->m_lsys_krn_readbios.addr; 22 dst.offset = m_ptr->m_lsys_krn_readbios.buf; 23 src.proc_nr_e = NONE; 24 dst.proc_nr_e = m_ptr->m_source; 25 26 limit = src.offset + len - 1; 27 28 #define VINRANGE(v, a, b) ((a) <= (v) && (v) <= (b)) 29 #define SUBRANGE(a,b,c,d) (VINRANGE((a), (c), (d)) && VINRANGE((b),(c),(d))) 30 #define USERRANGE(a, b) SUBRANGE(src.offset, limit, (a), (b)) 31 32 if(!USERRANGE(BIOS_MEM_BEGIN, BIOS_MEM_END) && 33 !USERRANGE(BASE_MEM_TOP, UPPER_MEM_END)) 34 return EPERM; 35 36 return virtual_copy_vmcheck(caller, &src, &dst, m_ptr->m_lsys_krn_readbios.size); 37 } 38