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/* The kernel call implemented in this file:
* m_type: SYS_READBIOS
*
* The parameters for this kernel call are:
* m_lsys_krn_readbios.size number of bytes to copy
* m_lsys_krn_readbios.addr absolute address in BIOS area
* m_lsys_krn_readbios.buf buffer address in requesting process
*/
#include "kernel/system.h"
/*===========================================================================*
* do_readbios *
*===========================================================================*/
int do_readbios(struct proc * caller, message * m_ptr)
{
struct vir_addr src, dst;
size_t len = m_ptr->m_lsys_krn_readbios.size;
vir_bytes limit;
src.offset = m_ptr->m_lsys_krn_readbios.addr;
dst.offset = m_ptr->m_lsys_krn_readbios.buf;
src.proc_nr_e = NONE;
dst.proc_nr_e = m_ptr->m_source;
limit = src.offset + len - 1;
#define VINRANGE(v, a, b) ((a) <= (v) && (v) <= (b))
#define SUBRANGE(a,b,c,d) (VINRANGE((a), (c), (d)) && VINRANGE((b),(c),(d)))
#define USERRANGE(a, b) SUBRANGE(src.offset, limit, (a), (b))
if(!USERRANGE(BIOS_MEM_BEGIN, BIOS_MEM_END) &&
!USERRANGE(BASE_MEM_TOP, UPPER_MEM_END))
return EPERM;
return virtual_copy_vmcheck(caller, &src, &dst, m_ptr->m_lsys_krn_readbios.size);
}
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