minix/kernel/system/do_mapdma.c

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2008-02-22 11:51:37 +01:00
/* The kernel call implemented in this file:
* m_type: SYS_MAPDMA
*
* The parameters for this kernel call are:
* m5_l1: CP_SRC_ADDR (virtual address)
* m5_l3: CP_NR_BYTES (size of datastructure)
*/
#include "../system.h"
/*==========================================================================*
* do_mapdma *
*==========================================================================*/
PUBLIC int do_mapdma(m_ptr)
register message *m_ptr; /* pointer to request message */
{
int r;
endpoint_t proc_e;
int proc_p;
vir_bytes base, size;
phys_bytes phys_base;
struct proc *proc;
message m;
proc_e = m_ptr->CP_SRC_ENDPT;
base= m_ptr->CP_SRC_ADDR;
size= m_ptr->CP_NR_BYTES;
if (!isokendpt(proc_e, &proc_p))
return(EINVAL);
proc = proc_addr(proc_p);
phys_base= umap_virtual(proc, D, base, size);
if (!phys_base)
{
kprintf("do_mapdma: umap_virtual failed\n");
2008-02-22 11:51:37 +01:00
return EFAULT;
}
m_ptr->CP_DST_ADDR = phys_base;
return OK;
}