minix/kernel/system/do_sdevio.c
Ben Gras 3061d7b17a Changed do_devio not to require DIO_TYPE, but to extract type
from DIO_REQUEST. Also do_vdevio. Also do_sdevio, but this
function also supports grant id's and offsets.

do_segctl: rename protected to prot.

do_umap: support for GRANT_SEG umap.

do_privctl: support SYS_PRIV_SET_GRANTS, which sets location and size
of in-own-address-space grant table.

do_safecopy: functions to verify and perform 'safe' (grant-based) copies.
2006-06-20 10:03:10 +00:00

84 lines
2.7 KiB
C

/* The kernel call implemented in this file:
* m_type: SYS_SDEVIO
*
* The parameters for this kernel call are:
* m2_i3: DIO_REQUEST (request input or output)
* m2_i1: DIO_TYPE (flag indicating byte, word, or long)
* m2_l1: DIO_PORT (port to read/ write)
* m2_p1: DIO_VEC_ADDR (virtual address of buffer)
* m2_l2: DIO_VEC_SIZE (number of elements)
* m2_i2: DIO_VEC_PROC (process where buffer is)
*/
#include "../system.h"
#include <minix/devio.h>
#include <minix/endpoint.h>
#if USE_SDEVIO
/*===========================================================================*
* do_sdevio *
*===========================================================================*/
PUBLIC int do_sdevio(m_ptr)
register message *m_ptr; /* pointer to request message */
{
int proc_nr, proc_nr_e = m_ptr->DIO_VEC_ENDPT;
int count = m_ptr->DIO_VEC_SIZE;
long port = m_ptr->DIO_PORT;
phys_bytes phys_buf;
int req_type, req_dir;
/* Check if process endpoint is OK.
* A driver may directly provide a pointer to a buffer at the user-process
* that initiated the device I/O. Kernel processes, of course, are denied.
*/
if (proc_nr_e == SELF)
proc_nr = who_p;
else
if(!isokendpt(proc_nr_e, &proc_nr))
return(EINVAL);
if (iskerneln(proc_nr)) return(EPERM);
/* Extract direction (in or out) and type (size). */
req_dir = m_ptr->DIO_REQUEST & _DIO_DIRMASK;
req_type = m_ptr->DIO_REQUEST & _DIO_TYPEMASK;
/* Check for 'safe' variants. */
if((m_ptr->DIO_REQUEST & _DIO_SAFEMASK) == _DIO_SAFE) {
/* Map grant address to physical address. */
if ((phys_buf = umap_verify_grant(proc_addr(proc_nr), who_e,
(vir_bytes) m_ptr->DIO_VEC_ADDR,
(vir_bytes) m_ptr->DIO_OFFSET, count,
req_dir == _DIO_INPUT ? CPF_WRITE : CPF_READ)) == 0)
return(EPERM);
} else {
if(proc_nr != who_p)
kprintf("unsafe sdevio by %d in %d\n", who_e, proc_nr_e);
/* Get and check physical address. */
if ((phys_buf = numap_local(proc_nr,
(vir_bytes) m_ptr->DIO_VEC_ADDR, count)) == 0)
return(EFAULT);
}
/* Perform device I/O for bytes and words. Longs are not supported. */
if (req_dir == _DIO_INPUT) {
switch (req_type) {
case _DIO_BYTE: phys_insb(port, phys_buf, count); break;
case _DIO_WORD: phys_insw(port, phys_buf, count); break;
default: return(EINVAL);
}
} else if (req_dir == _DIO_OUTPUT) {
switch (req_type) {
case _DIO_BYTE: phys_outsb(port, phys_buf, count); break;
case _DIO_WORD: phys_outsw(port, phys_buf, count); break;
default: return(EINVAL);
}
}
else {
return(EINVAL);
}
return(OK);
}
#endif /* USE_SDEVIO */