300 lines
7.2 KiB
C
300 lines
7.2 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 <errno.h>
|
|
#include <string.h>
|
|
#include <env.h>
|
|
#include <stdio.h>
|
|
#include <fcntl.h>
|
|
#include <signal.h>
|
|
#include <assert.h>
|
|
|
|
#include "glo.h"
|
|
#include "proto.h"
|
|
#include "util.h"
|
|
#include "region.h"
|
|
|
|
/*===========================================================================*
|
|
* pf_errstr *
|
|
*===========================================================================*/
|
|
char *pf_errstr(u32_t err)
|
|
{
|
|
static char buf[100];
|
|
|
|
sprintf(buf, "err 0x%lx ", (long)err);
|
|
if(PFERR_NOPAGE(err)) strcat(buf, "nopage ");
|
|
if(PFERR_PROT(err)) strcat(buf, "protection ");
|
|
if(PFERR_WRITE(err)) strcat(buf, "write");
|
|
if(PFERR_READ(err)) strcat(buf, "read");
|
|
|
|
return buf;
|
|
}
|
|
|
|
struct pf_state {
|
|
endpoint_t ep;
|
|
vir_bytes vaddr;
|
|
u32_t err;
|
|
};
|
|
|
|
struct hm_state {
|
|
endpoint_t requestor;
|
|
struct vmproc *vmp;
|
|
vir_bytes mem;
|
|
vir_bytes len;
|
|
int wrflag;
|
|
};
|
|
|
|
static void pf_cont(struct vmproc *vmp, message *m, void *arg, void *statearg);
|
|
|
|
static void hm_cont(struct vmproc *vmp, message *m, void *arg, void *statearg);
|
|
|
|
static void handle_pagefault(endpoint_t ep, vir_bytes addr, u32_t err, int retry)
|
|
{
|
|
struct vmproc *vmp;
|
|
int s, result;
|
|
struct vir_region *region;
|
|
vir_bytes offset;
|
|
int p, wr = PFERR_WRITE(err);
|
|
int io = 0;
|
|
|
|
if(vm_isokendpt(ep, &p) != OK)
|
|
panic("handle_pagefault: endpoint wrong: %d", ep);
|
|
|
|
vmp = &vmproc[p];
|
|
assert(vmp->vm_flags & VMF_INUSE);
|
|
|
|
/* See if address is valid at all. */
|
|
if(!(region = map_lookup(vmp, addr, NULL))) {
|
|
if(PFERR_PROT(err)) {
|
|
printf("VM: pagefault: SIGSEGV %d protected addr 0x%lx; %s\n",
|
|
ep, addr, pf_errstr(err));
|
|
} else {
|
|
assert(PFERR_NOPAGE(err));
|
|
printf("VM: pagefault: SIGSEGV %d bad addr 0x%lx; %s\n",
|
|
ep, addr, pf_errstr(err));
|
|
sys_sysctl_stacktrace(ep);
|
|
}
|
|
if((s=sys_kill(vmp->vm_endpoint, SIGSEGV)) != OK)
|
|
panic("sys_kill failed: %d", s);
|
|
if((s=sys_vmctl(ep, VMCTL_CLEAR_PAGEFAULT, 0 /*unused*/)) != OK)
|
|
panic("do_pagefaults: sys_vmctl failed: %d", ep);
|
|
return;
|
|
}
|
|
|
|
/* If process was writing, see if it's writable. */
|
|
if(!(region->flags & VR_WRITABLE) && wr) {
|
|
printf("VM: pagefault: SIGSEGV %d ro map 0x%lx %s\n",
|
|
ep, addr, pf_errstr(err));
|
|
if((s=sys_kill(vmp->vm_endpoint, SIGSEGV)) != OK)
|
|
panic("sys_kill failed: %d", s);
|
|
if((s=sys_vmctl(ep, VMCTL_CLEAR_PAGEFAULT, 0 /*unused*/)) != OK)
|
|
panic("do_pagefaults: sys_vmctl failed: %d", ep);
|
|
return;
|
|
}
|
|
|
|
assert(addr >= region->vaddr);
|
|
offset = addr - region->vaddr;
|
|
|
|
/* Access is allowed; handle it. */
|
|
if(retry) {
|
|
result = map_pf(vmp, region, offset, wr, NULL, NULL, 0, &io);
|
|
assert(result != SUSPEND);
|
|
} else {
|
|
struct pf_state state;
|
|
state.ep = ep;
|
|
state.vaddr = addr;
|
|
state.err = err;
|
|
result = map_pf(vmp, region, offset, wr, pf_cont,
|
|
&state, sizeof(state), &io);
|
|
}
|
|
if (io)
|
|
vmp->vm_major_page_fault++;
|
|
else
|
|
vmp->vm_minor_page_fault++;
|
|
|
|
if(result == SUSPEND) {
|
|
return;
|
|
}
|
|
|
|
if(result != OK) {
|
|
printf("VM: pagefault: SIGSEGV %d pagefault not handled\n", ep);
|
|
if((s=sys_kill(ep, SIGSEGV)) != OK)
|
|
panic("sys_kill failed: %d", s);
|
|
if((s=sys_vmctl(ep, VMCTL_CLEAR_PAGEFAULT, 0 /*unused*/)) != OK)
|
|
panic("do_pagefaults: sys_vmctl failed: %d", ep);
|
|
return;
|
|
}
|
|
|
|
pt_clearmapcache();
|
|
|
|
/* Pagefault is handled, so now reactivate the process. */
|
|
if((s=sys_vmctl(ep, VMCTL_CLEAR_PAGEFAULT, 0 /*unused*/)) != OK)
|
|
panic("do_pagefaults: sys_vmctl failed: %d", ep);
|
|
}
|
|
|
|
|
|
static void pf_cont(struct vmproc *vmp, message *m,
|
|
void *arg, void *statearg)
|
|
{
|
|
struct pf_state *state = statearg;
|
|
int p;
|
|
if(vm_isokendpt(state->ep, &p) != OK) return; /* signal */
|
|
handle_pagefault(state->ep, state->vaddr, state->err, 1);
|
|
}
|
|
|
|
static void hm_cont(struct vmproc *vmp, message *m,
|
|
void *arg, void *statearg)
|
|
{
|
|
int r;
|
|
struct hm_state *state = statearg;
|
|
printf("hm_cont: result %d\n", m->VMV_RESULT);
|
|
r = handle_memory(vmp, state->mem, state->len, state->wrflag,
|
|
hm_cont, &state, sizeof(state));
|
|
if(r == SUSPEND) {
|
|
printf("VM: hm_cont: damnit: hm_cont: more SUSPEND\n");
|
|
return;
|
|
}
|
|
|
|
printf("VM: hm_cont: ok, result %d, requestor %d\n", r, state->requestor);
|
|
|
|
if(sys_vmctl(state->requestor, VMCTL_MEMREQ_REPLY, r) != OK)
|
|
panic("hm_cont: sys_vmctl failed: %d", r);
|
|
|
|
printf("MEMREQ_REPLY sent\n");
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* do_pagefaults *
|
|
*===========================================================================*/
|
|
void do_pagefaults(message *m)
|
|
{
|
|
handle_pagefault(m->m_source, m->VPF_ADDR, m->VPF_FLAGS, 0);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* do_memory *
|
|
*===========================================================================*/
|
|
void do_memory(void)
|
|
{
|
|
endpoint_t who, who_s, requestor;
|
|
vir_bytes mem, mem_s;
|
|
vir_bytes len;
|
|
int wrflag;
|
|
|
|
while(1) {
|
|
int p, r = OK;
|
|
struct vmproc *vmp;
|
|
|
|
r = sys_vmctl_get_memreq(&who, &mem, &len, &wrflag, &who_s,
|
|
&mem_s, &requestor);
|
|
|
|
switch(r) {
|
|
case VMPTYPE_CHECK:
|
|
{
|
|
struct hm_state state;
|
|
|
|
if(vm_isokendpt(who, &p) != OK)
|
|
panic("do_memory: bad endpoint: %d", who);
|
|
vmp = &vmproc[p];
|
|
|
|
|
|
state.vmp = vmp;
|
|
state.mem = mem;
|
|
state.len = len;
|
|
state.wrflag = wrflag;
|
|
state.requestor = requestor;
|
|
|
|
r = handle_memory(vmp, mem, len,
|
|
wrflag, hm_cont, &state, sizeof(state));
|
|
|
|
break;
|
|
}
|
|
|
|
default:
|
|
return;
|
|
}
|
|
|
|
if(r != SUSPEND) {
|
|
if(sys_vmctl(requestor, VMCTL_MEMREQ_REPLY, r) != OK)
|
|
panic("do_memory: sys_vmctl failed: %d", r);
|
|
}
|
|
}
|
|
}
|
|
|
|
int handle_memory(struct vmproc *vmp, vir_bytes mem, vir_bytes len, int wrflag,
|
|
vfs_callback_t callback, void *state, int statelen)
|
|
{
|
|
struct vir_region *region;
|
|
vir_bytes o;
|
|
struct hm_state *hmstate = (struct hm_state *) state;
|
|
|
|
/* Page-align memory and length. */
|
|
o = mem % VM_PAGE_SIZE;
|
|
mem -= o;
|
|
len += o;
|
|
o = len % VM_PAGE_SIZE;
|
|
if(o > 0) len += VM_PAGE_SIZE - o;
|
|
|
|
while(len > 0) {
|
|
int r;
|
|
if(!(region = map_lookup(vmp, mem, NULL))) {
|
|
#if VERBOSE
|
|
map_printmap(vmp);
|
|
printf("VM: do_memory: memory doesn't exist\n");
|
|
#endif
|
|
r = EFAULT;
|
|
} else if(!(region->flags & VR_WRITABLE) && wrflag) {
|
|
#if VERBOSE
|
|
printf("VM: do_memory: write to unwritable map\n");
|
|
#endif
|
|
r = EFAULT;
|
|
} else {
|
|
vir_bytes offset, sublen;
|
|
assert(region->vaddr <= mem);
|
|
assert(!(region->vaddr % VM_PAGE_SIZE));
|
|
offset = mem - region->vaddr;
|
|
sublen = len;
|
|
if(offset + sublen > region->length)
|
|
sublen = region->length - offset;
|
|
|
|
if(hmstate && hmstate->requestor == VFS_PROC_NR
|
|
&& region->def_memtype == &mem_type_mappedfile) {
|
|
r = map_handle_memory(vmp, region, offset,
|
|
sublen, wrflag, NULL, NULL, 0);
|
|
} else {
|
|
r = map_handle_memory(vmp, region, offset,
|
|
sublen, wrflag, callback, state, sizeof(state));
|
|
}
|
|
|
|
len -= sublen;
|
|
mem += sublen;
|
|
}
|
|
|
|
if(r != OK) {
|
|
#if VERBOSE
|
|
printf("VM: memory range 0x%lx-0x%lx not available in %d\n",
|
|
mem, mem+len, vmp->vm_endpoint);
|
|
#endif
|
|
return r;
|
|
}
|
|
}
|
|
|
|
return OK;
|
|
}
|
|
|