minix/servers/vm/queryexit.c
Cristiano Giuffrida c5b309ff07 Merge of Wu's GSOC 09 branch (src.20090525.r4372.wu)
Main changes:
- COW optimization for safecopy.
- safemap, a grant-based interface for sharing memory regions between processes.
- Integration with safemap and complete rework of DS, supporting new data types
  natively (labels, memory ranges, memory mapped ranges).
- For further information:
  http://wiki.minix3.org/en/SummerOfCode2009/MemoryGrants

Additional changes not included in the original Wu's branch:
- Fixed unhandled case in VM when using COW optimization for safecopy in case
  of a block that has already been shared as SMAP.
- Better interface and naming scheme for sys_saferevmap and ds_retrieve_map
  calls.
- Better input checking in syslib: check for page alignment when creating
  memory mapping grants.
- DS notifies subscribers when an entry is deleted.
- Documented the behavior of indirect grants in case of memory mapping.
- Test suite in /usr/src/test/safeperf|safecopy|safemap|ds/* reworked
  and extended.
- Minor fixes and general cleanup.
- TO-DO: Grant ids should be generated and managed the way endpoints are to make
sure grant slots are never misreused.
2010-01-14 15:24:16 +00:00

122 lines
2.5 KiB
C

#define _SYSTEM 1
#include <minix/callnr.h>
#include <minix/com.h>
#include <minix/config.h>
#include <minix/const.h>
#include <minix/ds.h>
#include <minix/endpoint.h>
#include <minix/keymap.h>
#include <minix/minlib.h>
#include <minix/type.h>
#include <minix/ipc.h>
#include <minix/sysutil.h>
#include <minix/syslib.h>
#include <minix/safecopies.h>
#include <minix/bitmap.h>
#include <minix/vm.h>
#include <minix/ds.h>
#include <errno.h>
#include <string.h>
#include <env.h>
#include <stdio.h>
#include "glo.h"
#include "proto.h"
#include "util.h"
struct query_exit_struct {
int avail;
endpoint_t ep;
};
static struct query_exit_struct array[NR_PROCS];
/*===========================================================================*
* do_query_exit *
*===========================================================================*/
PUBLIC int do_query_exit(message *m)
{
int i, nr;
endpoint_t ep;
for (i = 0; i < NR_PROCS; i++) {
if (!array[i].avail) {
array[i].avail = 1;
ep = array[i].ep;
array[i].ep = 0;
break;
}
}
nr = 0;
for (i = 0; i < NR_PROCS; i++) {
if (!array[i].avail)
nr++;
}
m->VM_QUERY_RET_PT = ep;
m->VM_QUERY_IS_MORE = (nr > 0);
return OK;
}
/*===========================================================================*
* do_notify_sig *
*===========================================================================*/
PUBLIC int do_notify_sig(message *m)
{
int i, avails = 0;
endpoint_t ep = m->VM_NOTIFY_SIG_ENDPOINT;
endpoint_t ipc_ep = m->VM_NOTIFY_SIG_IPC;
int r;
for (i = 0; i < NR_PROCS; i++) {
/* its signal is already here */
if (!array[i].avail && array[i].ep == ep)
goto out;
if (array[i].avail)
avails++;
}
if (!avails) {
/* no slot for signals, impossible */
printf("VM: no slot for signals!\n");
return ENOMEM;
}
for (i = 0; i < NR_PROCS; i++) {
if (array[i].avail) {
array[i].avail = 0;
array[i].ep = ep;
break;
}
}
out:
/* only care when IPC server starts up,
* and bypass the process to be signal is IPC itself.
*/
if (ipc_ep != 0 && ep != ipc_ep) {
r = notify(ipc_ep);
if (r != OK)
printf("VM: notify IPC error!\n");
}
return OK;
}
/*===========================================================================*
* init_query_exit *
*===========================================================================*/
PUBLIC void init_query_exit(void)
{
int i;
for (i = 0; i < NR_PROCS; i++) {
array[i].avail = 1;
array[i].ep = 0;
}
}