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Basic VM and other minor improvements.

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Not complete, probably not fully debugged or optimized.
This commit is contained in:
Ben Gras
2008-11-19 12:26:10 +00:00
parent c888305e21
commit c078ec0331
273 changed files with 10814 additions and 4305 deletions
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372
kernel/system.c
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@@ -15,7 +15,6 @@
* send_sig: send a signal directly to a system process
* cause_sig: take action to cause a signal to occur via PM
* umap_bios: map virtual address in BIOS_SEG to physical
* virtual_copy: copy bytes from one virtual address to another
* get_randomness: accumulate randomness in a buffer
* clear_endpoint: remove a process' ability to send and receive messages
*
@@ -31,13 +30,16 @@
#include "kernel.h"
#include "system.h"
#include "proc.h"
#include "vm.h"
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <string.h>
#include <sys/sigcontext.h>
#include <minix/endpoint.h>
#include <minix/safecopies.h>
#include <minix/u64.h>
#include <sys/vm_i386.h>
/* Declaration of the call vector that defines the mapping of system calls
* to handler functions. The vector is initialized in sys_init() with map(),
@@ -46,12 +48,16 @@
* array size will be negative and this won't compile.
*/
PUBLIC int (*call_vec[NR_SYS_CALLS])(message *m_ptr);
char *callnames[NR_SYS_CALLS];
#define map(call_nr, handler) \
{extern int dummy[NR_SYS_CALLS>(unsigned)(call_nr-KERNEL_CALL) ? 1:-1];} \
callnames[(call_nr-KERNEL_CALL)] = #call_nr; \
call_vec[(call_nr-KERNEL_CALL)] = (handler)
FORWARD _PROTOTYPE( void initialize, (void));
FORWARD _PROTOTYPE( void softnotify_check, (void));
FORWARD _PROTOTYPE( struct proc *vmrestart_check, (message *));
/*===========================================================================*
* sys_task *
@@ -64,14 +70,39 @@ PUBLIC void sys_task()
register struct proc *caller_ptr;
int s;
int call_nr;
int n = 0;
/* Initialize the system task. */
initialize();
while (TRUE) {
int r;
/* Get work. Block and wait until a request message arrives. */
if((r=receive(ANY, &m)) != OK) panic("system: receive() failed", r);
struct proc *restarting;
#if 0
if(!(n++ % 100000)) {
int i;
kprintf("switch %8d reload %8d\n", cr3switch, cr3reload);
}
#endif
restarting = vmrestart_check(&m);
softnotify_check();
if(softnotify)
minix_panic("softnotify non-NULL before receive (1)", NO_NUM);
if(!restarting) {
int r;
/* Get work. Block and wait until a request message arrives. */
if(softnotify)
minix_panic("softnotify non-NULL before receive (2)", NO_NUM);
if((r=receive(ANY, &m)) != OK)
minix_panic("receive() failed", r);
if(m.m_source == SYSTEM)
continue;
if(softnotify)
minix_panic("softnotify non-NULL after receive", NO_NUM);
}
sys_call_code = (unsigned) m.m_type;
call_nr = sys_call_code - KERNEL_CALL;
who_e = m.m_source;
@@ -115,16 +146,34 @@ PUBLIC void sys_task()
result = (*call_vec[call_nr])(&m); /* handle the system call */
}
/* Send a reply, unless inhibited by a handler function. Use the kernel
* function lock_send() to prevent a system call trap. The destination
* is known to be blocked waiting for a message.
*/
if (result != EDONTREPLY) {
m.m_type = result; /* report status of call */
if (OK != (s=lock_send(m.m_source, &m))) {
kprintf("SYSTEM, reply to %d failed: %d\n", m.m_source, s);
}
}
if(result == VMSUSPEND) {
/* Special case: message has to be saved for handling
* until VM tells us it's allowed. VM has been notified
* and we must wait for its reply to restart the call.
*/
memcpy(&caller_ptr->p_vmrequest.saved.reqmsg, &m, sizeof(m));
caller_ptr->p_vmrequest.type = VMSTYPE_SYS_MESSAGE;
#if 0
kprintf("SYSTEM: suspending call from %d\n", m.m_source);
#endif
} else if (result != EDONTREPLY) {
/* Send a reply, unless inhibited by a handler function.
* Use the kernel function lock_send() to prevent a system
* call trap.
*/
if(restarting)
RTS_LOCK_UNSET(restarting, VMREQUEST);
m.m_type = result; /* report status of call */
if(WILLRECEIVE(caller_ptr, SYSTEM)) {
if (OK != (s=lock_send(m.m_source, &m))) {
kprintf("SYSTEM, reply to %d failed: %d\n",
m.m_source, s);
}
} else {
kprintf("SYSTEM: not replying to %d; not ready\n",
caller_ptr->p_endpoint);
}
}
}
}
@@ -153,6 +202,7 @@ PRIVATE void initialize(void)
*/
for (i=0; i<NR_SYS_CALLS; i++) {
call_vec[i] = do_unused;
callnames[i] = "unused";
}
/* Process management. */
@@ -181,14 +231,14 @@ PRIVATE void initialize(void)
map(SYS_SEGCTL, do_segctl); /* add segment and get selector */
map(SYS_MEMSET, do_memset); /* write char to memory area */
map(SYS_VM_SETBUF, do_vm_setbuf); /* PM passes buffer for page tables */
map(SYS_VM_MAP, do_vm_map); /* Map/unmap physical (device) memory */
map(SYS_VMCTL, do_vmctl); /* various VM process settings */
/* Copying. */
map(SYS_UMAP, do_umap); /* map virtual to physical address */
map(SYS_VIRCOPY, do_vircopy); /* use pure virtual addressing */
map(SYS_PHYSCOPY, do_physcopy); /* use physical addressing */
map(SYS_PHYSCOPY, do_copy); /* use physical addressing */
map(SYS_VIRVCOPY, do_virvcopy); /* vector with copy requests */
map(SYS_PHYSVCOPY, do_physvcopy); /* vector with copy requests */
map(SYS_PHYSVCOPY, do_vcopy); /* vector with copy requests */
map(SYS_SAFECOPYFROM, do_safecopy); /* copy with pre-granted permission */
map(SYS_SAFECOPYTO, do_safecopy); /* copy with pre-granted permission */
map(SYS_VSAFECOPY, do_vsafecopy); /* vectored safecopy */
@@ -279,19 +329,16 @@ PUBLIC void send_sig(int proc_nr, int sig_nr)
/* Notify a system process about a signal. This is straightforward. Simply
* set the signal that is to be delivered in the pending signals map and
* send a notification with source SYSTEM.
*
* Process number is verified to avoid writing in random places, but we
* don't kprintf() or panic() because that causes send_sig() invocations.
*/
register struct proc *rp;
static int n;
if(!isokprocn(proc_nr) || isemptyn(proc_nr))
return;
minix_panic("send_sig to empty process", proc_nr);
rp = proc_addr(proc_nr);
sigaddset(&priv(rp)->s_sig_pending, sig_nr);
lock_notify(SYSTEM, rp->p_endpoint);
soft_notify(rp->p_endpoint);
}
/*===========================================================================*
@@ -317,7 +364,7 @@ int sig_nr; /* signal to be sent, 1 to _NSIG */
register struct proc *rp;
if (proc_nr == PM_PROC_NR)
panic("cause_sig: PM gets signal", NO_NUM);
minix_panic("cause_sig: PM gets signal", NO_NUM);
/* Check if the signal is already pending. Process it otherwise. */
rp = proc_addr(proc_nr);
@@ -335,8 +382,7 @@ int sig_nr; /* signal to be sent, 1 to _NSIG */
/*===========================================================================*
* umap_bios *
*===========================================================================*/
PUBLIC phys_bytes umap_bios(rp, vir_addr, bytes)
register struct proc *rp; /* pointer to proc table entry for process */
PUBLIC phys_bytes umap_bios(vir_addr, bytes)
vir_bytes vir_addr; /* virtual address in BIOS segment */
vir_bytes bytes; /* # of bytes to be copied */
{
@@ -358,37 +404,6 @@ vir_bytes bytes; /* # of bytes to be copied */
}
#endif
/*===========================================================================*
* umap_verify_grant *
*===========================================================================*/
PUBLIC phys_bytes umap_verify_grant(rp, grantee, grant, offset, bytes, access)
struct proc *rp; /* pointer to proc table entry for process */
endpoint_t grantee; /* who wants to do this */
cp_grant_id_t grant; /* grant no. */
vir_bytes offset; /* offset into grant */
vir_bytes bytes; /* size */
int access; /* does grantee want to CPF_READ or _WRITE? */
{
int proc_nr;
vir_bytes v_offset;
endpoint_t granter;
/* See if the grant in that process is sensible, and
* find out the virtual address and (optionally) new
* process for that address.
*
* Then convert that process to a slot number.
*/
if(verify_grant(rp->p_endpoint, grantee, grant, bytes, access, offset,
&v_offset, &granter) != OK
|| !isokendpt(granter, &proc_nr)) {
return 0;
}
/* Do the mapping from virtual to physical. */
return umap_local(proc_addr(proc_nr), D, v_offset, bytes);
}
/*===========================================================================*
* umap_grant *
*===========================================================================*/
@@ -398,9 +413,9 @@ cp_grant_id_t grant; /* grant no. */
vir_bytes bytes; /* size */
{
int proc_nr;
vir_bytes offset;
vir_bytes offset, ret;
endpoint_t granter;
/* See if the grant in that process is sensible, and
* find out the virtual address and (optionally) new
* process for that address.
@@ -409,88 +424,25 @@ vir_bytes bytes; /* size */
*/
if(verify_grant(rp->p_endpoint, ANY, grant, bytes, 0, 0,
&offset, &granter) != OK) {
kprintf("SYSTEM: umap_grant: verify_grant failed\n");
return 0;
}
if(!isokendpt(granter, &proc_nr)) {
kprintf("SYSTEM: umap_grant: isokendpt failed\n");
return 0;
}
/* Do the mapping from virtual to physical. */
return umap_local(proc_addr(proc_nr), D, offset, bytes);
ret = umap_virtual(proc_addr(proc_nr), D, offset, bytes);
if(!ret) {
kprintf("SYSTEM:umap_grant:umap_virtual failed; grant %s:%d -> %s: vir 0x%lx\n",
rp->p_name, grant,
proc_addr(proc_nr)->p_name, offset);
}
return ret;
}
/*===========================================================================*
* virtual_copy *
*===========================================================================*/
PUBLIC int virtual_copy(src_addr, dst_addr, bytes)
struct vir_addr *src_addr; /* source virtual address */
struct vir_addr *dst_addr; /* destination virtual address */
vir_bytes bytes; /* # of bytes to copy */
{
/* Copy bytes from virtual address src_addr to virtual address dst_addr.
* Virtual addresses can be in ABS, LOCAL_SEG, REMOTE_SEG, or BIOS_SEG.
*/
struct vir_addr *vir_addr[2]; /* virtual source and destination address */
phys_bytes phys_addr[2]; /* absolute source and destination */
int seg_index;
int i;
/* Check copy count. */
if (bytes <= 0) return(EDOM);
/* Do some more checks and map virtual addresses to physical addresses. */
vir_addr[_SRC_] = src_addr;
vir_addr[_DST_] = dst_addr;
for (i=_SRC_; i<=_DST_; i++) {
int proc_nr, type;
struct proc *p;
type = vir_addr[i]->segment & SEGMENT_TYPE;
if(type != PHYS_SEG && isokendpt(vir_addr[i]->proc_nr_e, &proc_nr))
p = proc_addr(proc_nr);
else
p = NULL;
/* Get physical address. */
switch(type) {
case LOCAL_SEG:
if(!p) return EDEADSRCDST;
seg_index = vir_addr[i]->segment & SEGMENT_INDEX;
phys_addr[i] = umap_local(p, seg_index, vir_addr[i]->offset, bytes);
break;
case REMOTE_SEG:
if(!p) return EDEADSRCDST;
seg_index = vir_addr[i]->segment & SEGMENT_INDEX;
phys_addr[i] = umap_remote(p, seg_index, vir_addr[i]->offset, bytes);
break;
#if _MINIX_CHIP == _CHIP_INTEL
case BIOS_SEG:
if(!p) return EDEADSRCDST;
phys_addr[i] = umap_bios(p, vir_addr[i]->offset, bytes );
break;
#endif
case PHYS_SEG:
phys_addr[i] = vir_addr[i]->offset;
break;
case GRANT_SEG:
phys_addr[i] = umap_grant(p, vir_addr[i]->offset, bytes);
break;
default:
return(EINVAL);
}
/* Check if mapping succeeded. */
if (phys_addr[i] <= 0 && vir_addr[i]->segment != PHYS_SEG)
return(EFAULT);
}
/* Now copy bytes between physical addresseses. */
phys_copy(phys_addr[_SRC_], phys_addr[_DST_], (phys_bytes) bytes);
return(OK);
}
/*===========================================================================*
* clear_endpoint *
*===========================================================================*/
@@ -499,8 +451,22 @@ register struct proc *rc; /* slot of process to clean up */
{
register struct proc *rp; /* iterate over process table */
register struct proc **xpp; /* iterate over caller queue */
struct proc *np;
if(isemptyp(rc)) panic("clear_proc: empty process", proc_nr(rc));
if(isemptyp(rc)) minix_panic("clear_proc: empty process", proc_nr(rc));
#if 1
if(rc->p_endpoint == PM_PROC_NR || rc->p_endpoint == VFS_PROC_NR) {
/* This test is great for debugging system processes dying,
* but as this happens normally on reboot, not good permanent code.
*/
kprintf("process %s / %d died; stack: ", rc->p_name, rc->p_endpoint);
proc_stacktrace(rc);
kprintf("kernel trace: ");
util_stacktrace();
minix_panic("clear_proc: system process died", rc->p_endpoint);
}
#endif
/* Make sure that the exiting process is no longer scheduled. */
RTS_LOCK_SET(rc, NO_ENDPOINT);
@@ -550,7 +516,8 @@ register struct proc *rc; /* slot of process to clean up */
rp->p_reg.retreg = ESRCDIED; /* report source died */
RTS_LOCK_UNSET(rp, RECEIVING); /* no longer receiving */
#if DEBUG_ENABLE_IPC_WARNINGS
kprintf("Proc %d receive dead src %d\n", proc_nr(rp), proc_nr(rc));
kprintf("Proc %d (%s) receiving from dead src %d (%s)\n",
proc_nr(rp), rp->p_name, proc_nr(rc), rc->p_name);
#endif
}
if (RTS_ISSET(rp, SENDING) &&
@@ -558,8 +525,147 @@ register struct proc *rc; /* slot of process to clean up */
rp->p_reg.retreg = EDSTDIED; /* report destination died */
RTS_LOCK_UNSET(rp, SENDING);
#if DEBUG_ENABLE_IPC_WARNINGS
kprintf("Proc %d send dead dst %d\n", proc_nr(rp), proc_nr(rc));
kprintf("Proc %d (%s) send to dying dst %d (%s)\n",
proc_nr(rp), rp->p_name, proc_nr(rc), rc->p_name);
#endif
}
}
/* No pending soft notifies. */
for(np = softnotify; np; np = np->next_soft_notify) {
if(np == rc) {
minix_panic("dying proc was on next_soft_notify", np->p_endpoint);
}
}
}
/*===========================================================================*
* umap_verify_grant *
*===========================================================================*/
PUBLIC phys_bytes umap_verify_grant(rp, grantee, grant, offset, bytes, access)
struct proc *rp; /* pointer to proc table entry for process */
endpoint_t grantee; /* who wants to do this */
cp_grant_id_t grant; /* grant no. */
vir_bytes offset; /* offset into grant */
vir_bytes bytes; /* size */
int access; /* does grantee want to CPF_READ or _WRITE? */
{
int proc_nr;
vir_bytes v_offset;
endpoint_t granter;
/* See if the grant in that process is sensible, and
* find out the virtual address and (optionally) new
* process for that address.
*
* Then convert that process to a slot number.
*/
if(verify_grant(rp->p_endpoint, grantee, grant, bytes, access, offset,
&v_offset, &granter) != OK
|| !isokendpt(granter, &proc_nr)) {
return 0;
}
/* Do the mapping from virtual to physical. */
return umap_virtual(proc_addr(proc_nr), D, v_offset, bytes);
}
/*===========================================================================*
* softnotify_check *
*===========================================================================*/
PRIVATE void softnotify_check(void)
{
struct proc *np, *nextnp;
if(!softnotify)
return;
for(np = softnotify; np; np = nextnp) {
if(!np->p_softnotified)
minix_panic("softnotify but no p_softnotified", NO_NUM);
lock_notify(SYSTEM, np->p_endpoint);
nextnp = np->next_soft_notify;
np->next_soft_notify = NULL;
np->p_softnotified = 0;
}
softnotify = NULL;
}
/*===========================================================================*
* vmrestart_check *
*===========================================================================*/
PRIVATE struct proc *vmrestart_check(message *m)
{
int type, r;
struct proc *restarting;
/* Anyone waiting to be vm-restarted? */
if(!(restarting = vmrestart))
return NULL;
if(restarting->p_rts_flags & SLOT_FREE)
minix_panic("SYSTEM: VMREQUEST set for empty process", NO_NUM);
type = restarting->p_vmrequest.type;
restarting->p_vmrequest.type = VMSTYPE_SYS_NONE;
vmrestart = restarting->p_vmrequest.nextrestart;
if(!RTS_ISSET(restarting, VMREQUEST))
minix_panic("SYSTEM: VMREQUEST not set for process on vmrestart queue",
restarting->p_endpoint);
switch(type) {
case VMSTYPE_SYS_MESSAGE:
memcpy(m, &restarting->p_vmrequest.saved.reqmsg, sizeof(*m));
#if 0
kprintf("SYSTEM: restart sys_message type %d / %lx source %d\n",
m->m_type, m->m_type, m->m_source);
#endif
if(m->m_source != restarting->p_endpoint)
minix_panic("SYSTEM: vmrestart source doesn't match",
NO_NUM);
/* Original caller could've disappeared in the meantime. */
if(!isokendpt(m->m_source, &who_p)) {
kprintf("SYSTEM: ignoring call %d from dead %d\n",
m->m_type, m->m_source);
return NULL;
}
{ int i;
i = m->m_type - KERNEL_CALL;
if(i >= 0 && i < NR_SYS_CALLS) {
#if 0
kprintf("SYSTEM: restart %s from %d\n",
callnames[i], m->m_source);
#endif
} else {
minix_panic("call number out of range", i);
}
}
return restarting;
case VMSTYPE_SYS_CALL:
kprintf("SYSTEM: restart sys_call\n");
/* Restarting a kernel trap. */
sys_call_restart(restarting);
/* Handled; restart system loop. */
return NULL;
case VMSTYPE_MSGCOPY:
/* Do delayed message copy. */
if((r=data_copy(SYSTEM,
(vir_bytes) &restarting->p_vmrequest.saved.msgcopy.msgbuf,
restarting->p_vmrequest.saved.msgcopy.dst->p_endpoint,
(vir_bytes) restarting->p_vmrequest.saved.msgcopy.dst_v,
sizeof(message))) != OK) {
minix_panic("SYSTEM: delayed msgcopy failed", r);
}
RTS_LOCK_UNSET(restarting, VMREQUEST);
/* Handled; restart system loop. */
return NULL;
default:
minix_panic("strange restart type", type);
}
minix_panic("fell out of switch", NO_NUM);
}