minix/servers/vm/main.c
Ben Gras 49b9165251 vm: mmap support
. test74 for mmap functionality
	. vm: add a mem_file memory type that specifies an mmap()ped
	  memory range, backed by a file
	. add fdref, an object that keeps track of FD references within
	  VM per process and so knows how to de-duplicate the use of FD's
	  by various mmap()ped ranges; there can be many more than there can
	  be FD's
	. turned off for now, enable with 'filemap=1' as boot option

Change-Id: I640b1126cdaa522a0560301cf6732b7661555672
2013-05-31 15:42:01 +00:00

516 lines
13 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/const.h>
#include <minix/bitmap.h>
#include <minix/crtso.h>
#include <minix/rs.h>
#include <libexec.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <env.h>
#include <stdio.h>
#include <assert.h>
#define _MAIN 1
#include "glo.h"
#include "proto.h"
#include "util.h"
#include "vm.h"
#include "sanitycheck.h"
extern int missing_spares;
#include <machine/archtypes.h>
#include <sys/param.h>
#include "kernel/const.h"
#include "kernel/config.h"
#include "kernel/proc.h"
#include <signal.h>
/* Table of calls and a macro to test for being in range. */
struct {
int (*vmc_func)(message *); /* Call handles message. */
char *vmc_name; /* Human-readable string. */
} vm_calls[NR_VM_CALLS];
/* Macro to verify call range and map 'high' range to 'base' range
* (starting at 0) in one. Evaluates to zero-based call number if call
* number is valid, returns -1 otherwise.
*/
#define CALLNUMBER(c) (((c) >= VM_RQ_BASE && \
(c) < VM_RQ_BASE + ELEMENTS(vm_calls)) ? \
((c) - VM_RQ_BASE) : -1)
static int map_service(struct rprocpub *rpub);
static int vm_acl_ok(endpoint_t caller, int call);
static int do_rs_init(message *m);
/* SEF functions and variables. */
static void sef_cb_signal_handler(int signo);
void init_vm(void);
/*===========================================================================*
* main *
*===========================================================================*/
int main(void)
{
message msg;
int result, who_e, rcv_sts;
int caller_slot;
/* Initialize system so that all processes are runnable */
init_vm();
/* Register init callbacks. */
sef_setcb_init_restart(sef_cb_init_fail);
sef_setcb_signal_handler(sef_cb_signal_handler);
/* Let SEF perform startup. */
sef_startup();
SANITYCHECK(SCL_TOP);
/* This is VM's main loop. */
while (TRUE) {
int r, c;
u32_t type, param;
SANITYCHECK(SCL_TOP);
if(missing_spares > 0) {
alloc_cycle(); /* mem alloc code wants to be called */
}
if ((r=sef_receive_status(ANY, &msg, &rcv_sts)) != OK)
panic("sef_receive_status() error: %d", r);
if (is_ipc_notify(rcv_sts)) {
/* Unexpected notify(). */
printf("VM: ignoring notify() from %d\n", msg.m_source);
continue;
}
who_e = msg.m_source;
if(vm_isokendpt(who_e, &caller_slot) != OK)
panic("invalid caller %d", who_e);
type = param = msg.m_type;
type &= 0x0000FFFF;
param >>= 16;
c = CALLNUMBER(type);
result = ENOSYS; /* Out of range or restricted calls return this. */
if(msg.m_type == RS_INIT && msg.m_source == RS_PROC_NR) {
result = do_rs_init(&msg);
} else if (msg.m_type == VM_PAGEFAULT) {
if (!IPC_STATUS_FLAGS_TEST(rcv_sts, IPC_FLG_MSG_FROM_KERNEL)) {
printf("VM: process %d faked VM_PAGEFAULT "
"message!\n", msg.m_source);
}
do_pagefaults(&msg);
/*
* do not reply to this call, the caller is unblocked by
* a sys_vmctl() call in do_pagefaults if success. VM panics
* otherwise
*/
continue;
} else if(c < 0 || !vm_calls[c].vmc_func) {
/* out of range or missing callnr */
} else {
if (vm_acl_ok(who_e, c) != OK) {
printf("VM: unauthorized %s by %d\n",
vm_calls[c].vmc_name, who_e);
} else {
SANITYCHECK(SCL_FUNCTIONS);
result = vm_calls[c].vmc_func(&msg);
SANITYCHECK(SCL_FUNCTIONS);
}
}
/* Send reply message, unless the return code is SUSPEND,
* which is a pseudo-result suppressing the reply message.
*/
if(result != SUSPEND) {
msg.m_type = result;
if((r=send(who_e, &msg)) != OK) {
printf("VM: couldn't send %d to %d (err %d)\n",
msg.m_type, who_e, r);
panic("send() error");
}
}
}
return(OK);
}
static int do_rs_init(message *m)
{
int s, i;
static struct rprocpub rprocpub[NR_BOOT_PROCS];
/* Map all the services in the boot image. */
if((s = sys_safecopyfrom(RS_PROC_NR, m->RS_INIT_RPROCTAB_GID, 0,
(vir_bytes) rprocpub, sizeof(rprocpub))) != OK) {
panic("vm: sys_safecopyfrom (rs) failed: %d", s);
}
for(i=0;i < NR_BOOT_PROCS;i++) {
if(rprocpub[i].in_use) {
if((s = map_service(&rprocpub[i])) != OK) {
panic("unable to map service: %d", s);
}
}
}
/* RS expects this response that it then again wants to reply to: */
m->RS_INIT_RESULT = OK;
sendrec(RS_PROC_NR, m);
return(SUSPEND);
}
struct vmproc *init_proc(endpoint_t ep_nr)
{
static struct boot_image *ip;
for (ip = &kernel_boot_info.boot_procs[0];
ip < &kernel_boot_info.boot_procs[NR_BOOT_PROCS]; ip++) {
struct vmproc *vmp;
if(ip->proc_nr != ep_nr) continue;
if(ip->proc_nr >= _NR_PROCS || ip->proc_nr < 0)
panic("proc: %d", ip->proc_nr);
vmp = &vmproc[ip->proc_nr];
assert(!(vmp->vm_flags & VMF_INUSE)); /* no double procs */
clear_proc(vmp);
vmp->vm_flags = VMF_INUSE;
vmp->vm_endpoint = ip->endpoint;
vmp->vm_boot = ip;
return vmp;
}
panic("no init_proc");
}
struct vm_exec_info {
struct exec_info execi;
struct boot_image *ip;
struct vmproc *vmp;
};
static int libexec_copy_physcopy(struct exec_info *execi,
off_t off, off_t vaddr, size_t len)
{
vir_bytes end;
struct vm_exec_info *ei = execi->opaque;
end = ei->ip->start_addr + ei->ip->len;
assert(ei->ip->start_addr + off + len <= end);
return sys_physcopy(NONE, ei->ip->start_addr + off,
execi->proc_e, vaddr, len);
}
static void boot_alloc(struct exec_info *execi, off_t vaddr,
size_t len, int flags)
{
struct vmproc *vmp = ((struct vm_exec_info *) execi->opaque)->vmp;
if(!(map_page_region(vmp, vaddr, 0, len,
VR_ANON | VR_WRITABLE | VR_UNINITIALIZED, flags,
&mem_type_anon))) {
panic("VM: exec: map_page_region for boot process failed");
}
}
static int libexec_alloc_vm_prealloc(struct exec_info *execi,
off_t vaddr, size_t len)
{
boot_alloc(execi, vaddr, len, MF_PREALLOC);
return OK;
}
static int libexec_alloc_vm_ondemand(struct exec_info *execi,
off_t vaddr, size_t len)
{
boot_alloc(execi, vaddr, len, 0);
return OK;
}
void exec_bootproc(struct vmproc *vmp, struct boot_image *ip)
{
struct vm_exec_info vmexeci;
struct exec_info *execi = &vmexeci.execi;
char hdr[VM_PAGE_SIZE];
memset(&vmexeci, 0, sizeof(vmexeci));
if(pt_new(&vmp->vm_pt) != OK)
panic("VM: no new pagetable");
if(pt_bind(&vmp->vm_pt, vmp) != OK)
panic("VM: pt_bind failed");
if(sys_physcopy(NONE, ip->start_addr, SELF,
(vir_bytes) hdr, sizeof(hdr)) != OK)
panic("can't look at boot proc header");
execi->stack_high = kernel_boot_info.user_sp;
execi->stack_size = DEFAULT_STACK_LIMIT;
execi->proc_e = vmp->vm_endpoint;
execi->hdr = hdr;
execi->hdr_len = sizeof(hdr);
strlcpy(execi->progname, ip->proc_name, sizeof(execi->progname));
execi->frame_len = 0;
execi->opaque = &vmexeci;
execi->filesize = ip->len;
vmexeci.ip = ip;
vmexeci.vmp = vmp;
/* callback functions and data */
execi->copymem = libexec_copy_physcopy;
execi->clearproc = NULL;
execi->clearmem = libexec_clear_sys_memset;
execi->allocmem_prealloc_junk = libexec_alloc_vm_prealloc;
execi->allocmem_prealloc_cleared = libexec_alloc_vm_prealloc;
execi->allocmem_ondemand = libexec_alloc_vm_ondemand;
if(libexec_load_elf(execi) != OK)
panic("vm: boot process load of process %s (ep=%d) failed\n",
execi->progname,vmp->vm_endpoint);
if(sys_exec(vmp->vm_endpoint, (char *) execi->stack_high - 12,
(char *) ip->proc_name, execi->pc) != OK)
panic("vm: boot process exec of process %s (ep=%d) failed\n",
execi->progname,vmp->vm_endpoint);
/* make it runnable */
if(sys_vmctl(vmp->vm_endpoint, VMCTL_BOOTINHIBIT_CLEAR, 0) != OK)
panic("VMCTL_BOOTINHIBIT_CLEAR failed");
}
void init_vm(void)
{
int s, i;
static struct memory mem_chunks[NR_MEMS];
static struct boot_image *ip;
extern void __minix_init(void);
multiboot_module_t *mod;
vir_bytes kern_dyn, kern_static;
#if SANITYCHECKS
incheck = nocheck = 0;
#endif
/* Retrieve various crucial boot parameters */
if(OK != (s=sys_getkinfo(&kernel_boot_info))) {
panic("couldn't get bootinfo: %d", s);
}
/* Turn file mmap on? */
env_parse("filemap", "d", 0, &enable_filemap, 0, 1);
/* Sanity check */
assert(kernel_boot_info.mmap_size > 0);
assert(kernel_boot_info.mods_with_kernel > 0);
/* Get chunks of available memory. */
get_mem_chunks(mem_chunks);
/* Set table to 0. This invalidates all slots (clear VMF_INUSE). */
memset(vmproc, 0, sizeof(vmproc));
for(i = 0; i < ELEMENTS(vmproc); i++) {
vmproc[i].vm_slot = i;
}
/* region management initialization. */
map_region_init();
/* Initialize tables to all physical memory. */
mem_init(mem_chunks);
/* Architecture-dependent initialization. */
init_proc(VM_PROC_NR);
pt_init();
/* The kernel's freelist does not include boot-time modules; let
* the allocator know that the total memory is bigger.
*/
for (mod = &kernel_boot_info.module_list[0];
mod < &kernel_boot_info.module_list[kernel_boot_info.mods_with_kernel-1]; mod++) {
phys_bytes len = mod->mod_end-mod->mod_start+1;
len = roundup(len, VM_PAGE_SIZE);
mem_add_total_pages(len/VM_PAGE_SIZE);
}
kern_dyn = kernel_boot_info.kernel_allocated_bytes_dynamic;
kern_static = kernel_boot_info.kernel_allocated_bytes;
kern_static = roundup(kern_static, VM_PAGE_SIZE);
mem_add_total_pages((kern_dyn + kern_static)/VM_PAGE_SIZE);
/* Give these processes their own page table. */
for (ip = &kernel_boot_info.boot_procs[0];
ip < &kernel_boot_info.boot_procs[NR_BOOT_PROCS]; ip++) {
struct vmproc *vmp;
if(ip->proc_nr < 0) continue;
assert(ip->start_addr);
/* VM has already been set up by the kernel and pt_init().
* Any other boot process is already in memory and is set up
* here.
*/
if(ip->proc_nr == VM_PROC_NR) continue;
vmp = init_proc(ip->proc_nr);
exec_bootproc(vmp, ip);
/* Free the file blob */
assert(!(ip->start_addr % VM_PAGE_SIZE));
ip->len = roundup(ip->len, VM_PAGE_SIZE);
free_mem(ABS2CLICK(ip->start_addr), ABS2CLICK(ip->len));
}
/* Set up table of calls. */
#define CALLMAP(code, func) { int i; \
i=CALLNUMBER(code); \
assert(i >= 0); \
assert(i < NR_VM_CALLS); \
vm_calls[i].vmc_func = (func); \
vm_calls[i].vmc_name = #code; \
}
/* Set call table to 0. This invalidates all calls (clear
* vmc_func).
*/
memset(vm_calls, 0, sizeof(vm_calls));
/* Basic VM calls. */
CALLMAP(VM_MMAP, do_mmap);
CALLMAP(VM_MUNMAP, do_munmap);
CALLMAP(VM_MAP_PHYS, do_map_phys);
CALLMAP(VM_UNMAP_PHYS, do_munmap);
/* Calls from PM. */
CALLMAP(VM_EXIT, do_exit);
CALLMAP(VM_FORK, do_fork);
CALLMAP(VM_BRK, do_brk);
CALLMAP(VM_WILLEXIT, do_willexit);
CALLMAP(VM_NOTIFY_SIG, do_notify_sig);
/* Calls from VFS. */
CALLMAP(VM_VFS_REPLY, do_vfs_reply);
CALLMAP(VM_VFS_MMAP, do_vfs_mmap);
/* Calls from RS */
CALLMAP(VM_RS_SET_PRIV, do_rs_set_priv);
CALLMAP(VM_RS_UPDATE, do_rs_update);
CALLMAP(VM_RS_MEMCTL, do_rs_memctl);
/* Calls from RS/VFS */
CALLMAP(VM_PROCCTL, do_procctl);
/* Generic calls. */
CALLMAP(VM_REMAP, do_remap);
CALLMAP(VM_REMAP_RO, do_remap);
CALLMAP(VM_GETPHYS, do_get_phys);
CALLMAP(VM_SHM_UNMAP, do_munmap);
CALLMAP(VM_GETREF, do_get_refcount);
CALLMAP(VM_INFO, do_info);
CALLMAP(VM_QUERY_EXIT, do_query_exit);
CALLMAP(VM_WATCH_EXIT, do_watch_exit);
/* Cache blocks. */
CALLMAP(VM_MAPCACHEPAGE, do_mapcache);
CALLMAP(VM_SETCACHEPAGE, do_setcache);
/* Initialize the structures for queryexit */
init_query_exit();
/* Acquire kernel ipc vectors that weren't available
* before VM had determined kernel mappings
*/
__minix_init();
}
/*===========================================================================*
* sef_cb_signal_handler *
*===========================================================================*/
static void sef_cb_signal_handler(int signo)
{
/* Check for known kernel signals, ignore anything else. */
switch(signo) {
/* There is a pending memory request from the kernel. */
case SIGKMEM:
do_memory();
break;
}
/* It can happen that we get stuck receiving signals
* without sef_receive() returning. We could need more memory
* though.
*/
if(missing_spares > 0) {
alloc_cycle(); /* pagetable code wants to be called */
}
pt_clearmapcache();
}
/*===========================================================================*
* map_service *
*===========================================================================*/
static int map_service(rpub)
struct rprocpub *rpub;
{
/* Map a new service by initializing its call mask. */
int r, proc_nr;
if ((r = vm_isokendpt(rpub->endpoint, &proc_nr)) != OK) {
return r;
}
/* Copy the call mask. */
memcpy(&vmproc[proc_nr].vm_call_mask, &rpub->vm_call_mask,
sizeof(vmproc[proc_nr].vm_call_mask));
return(OK);
}
/*===========================================================================*
* vm_acl_ok *
*===========================================================================*/
static int vm_acl_ok(endpoint_t caller, int call)
{
int n, r;
if ((r = vm_isokendpt(caller, &n)) != OK)
panic("VM: from strange source: %d", caller);
/* See if the call is allowed. */
if (!GET_BIT(vmproc[n].vm_call_mask, call)) {
return EPERM;
}
return OK;
}