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|
/*-
* Copyright (c) 1982, 1986 The Regents of the University of California.
* Copyright (c) 1989, 1990 William Jolitz
* Copyright (c) 1994 John Dyson
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department, and William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91
* Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$
* $Id: vm_machdep.c,v 1.28 1994/09/02 04:12:07 davidg Exp $
*/
#include "npx.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/buf.h>
#include <sys/vnode.h>
#include <sys/user.h>
#include <machine/cpu.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
#ifdef BOUNCE_BUFFERS
vm_map_t io_map;
volatile int kvasfreecnt;
caddr_t bouncememory;
int bouncepages, bpwait;
vm_offset_t *bouncepa;
int bmwait, bmfreeing;
#define BITS_IN_UNSIGNED (8*sizeof(unsigned))
int bounceallocarraysize;
unsigned *bounceallocarray;
int bouncefree;
#define SIXTEENMEG (4096*4096)
#define MAXBKVA 1024
int maxbkva = MAXBKVA*NBPG;
/* special list that can be used at interrupt time for eventual kva free */
struct kvasfree {
vm_offset_t addr;
vm_offset_t size;
} kvaf[MAXBKVA];
vm_offset_t vm_bounce_kva();
/*
* get bounce buffer pages (count physically contiguous)
* (only 1 inplemented now)
*/
vm_offset_t
vm_bounce_page_find(count)
int count;
{
int bit;
int s,i;
if (count != 1)
panic("vm_bounce_page_find -- no support for > 1 page yet!!!");
s = splbio();
retry:
for (i = 0; i < bounceallocarraysize; i++) {
if (bounceallocarray[i] != 0xffffffff) {
bit = ffs(~bounceallocarray[i]);
if (bit) {
bounceallocarray[i] |= 1 << (bit - 1) ;
bouncefree -= count;
splx(s);
return bouncepa[(i * BITS_IN_UNSIGNED + (bit - 1))];
}
}
}
bpwait = 1;
tsleep((caddr_t) &bounceallocarray, PRIBIO, "bncwai", 0);
goto retry;
}
void
vm_bounce_kva_free(addr, size, now)
vm_offset_t addr;
vm_offset_t size;
int now;
{
int s = splbio();
kvaf[kvasfreecnt].addr = addr;
kvaf[kvasfreecnt].size = size;
++kvasfreecnt;
if( now) {
/*
* this will do wakeups
*/
vm_bounce_kva(0,0);
} else {
if (bmwait) {
/*
* if anyone is waiting on the bounce-map, then wakeup
*/
wakeup((caddr_t) io_map);
bmwait = 0;
}
}
splx(s);
}
/*
* free count bounce buffer pages
*/
void
vm_bounce_page_free(pa, count)
vm_offset_t pa;
int count;
{
int allocindex;
int index;
int bit;
if (count != 1)
panic("vm_bounce_page_free -- no support for > 1 page yet!!!\n");
for(index=0;index<bouncepages;index++) {
if( pa == bouncepa[index])
break;
}
if( index == bouncepages)
panic("vm_bounce_page_free: invalid bounce buffer");
allocindex = index / BITS_IN_UNSIGNED;
bit = index % BITS_IN_UNSIGNED;
bounceallocarray[allocindex] &= ~(1 << bit);
bouncefree += count;
if (bpwait) {
bpwait = 0;
wakeup((caddr_t) &bounceallocarray);
}
}
/*
* allocate count bounce buffer kva pages
*/
vm_offset_t
vm_bounce_kva(size, waitok)
int size;
int waitok;
{
int i;
vm_offset_t kva = 0;
vm_offset_t off;
int s = splbio();
more:
if (!bmfreeing && kvasfreecnt) {
bmfreeing = 1;
for (i = 0; i < kvasfreecnt; i++) {
for(off=0;off<kvaf[i].size;off+=NBPG) {
pmap_kremove( kvaf[i].addr + off);
}
kmem_free_wakeup(io_map, kvaf[i].addr,
kvaf[i].size);
}
kvasfreecnt = 0;
bmfreeing = 0;
if( bmwait) {
bmwait = 0;
wakeup( (caddr_t) io_map);
}
}
if( size == 0) {
splx(s);
return NULL;
}
if ((kva = kmem_alloc_pageable(io_map, size)) == 0) {
if( !waitok) {
splx(s);
return NULL;
}
bmwait = 1;
tsleep((caddr_t) io_map, PRIBIO, "bmwait", 0);
goto more;
}
splx(s);
return kva;
}
/*
* same as vm_bounce_kva -- but really allocate (but takes pages as arg)
*/
vm_offset_t
vm_bounce_kva_alloc(count)
int count;
{
int i;
vm_offset_t kva;
vm_offset_t pa;
if( bouncepages == 0) {
kva = (vm_offset_t) malloc(count*NBPG, M_TEMP, M_WAITOK);
return kva;
}
kva = vm_bounce_kva(count*NBPG, 1);
for(i=0;i<count;i++) {
pa = vm_bounce_page_find(1);
pmap_kenter(kva + i * NBPG, pa);
}
return kva;
}
/*
* same as vm_bounce_kva_free -- but really free
*/
void
vm_bounce_kva_alloc_free(kva, count)
vm_offset_t kva;
int count;
{
int i;
vm_offset_t pa;
if( bouncepages == 0) {
free((caddr_t) kva, M_TEMP);
return;
}
for(i = 0; i < count; i++) {
pa = pmap_kextract(kva + i * NBPG);
vm_bounce_page_free(pa, 1);
}
vm_bounce_kva_free(kva, count*NBPG, 0);
}
/*
* do the things necessary to the struct buf to implement
* bounce buffers... inserted before the disk sort
*/
void
vm_bounce_alloc(bp)
struct buf *bp;
{
int countvmpg;
vm_offset_t vastart, vaend;
vm_offset_t vapstart, vapend;
vm_offset_t va, kva;
vm_offset_t pa;
int dobounceflag = 0;
int i;
if (bouncepages == 0)
return;
if (bp->b_flags & B_BOUNCE) {
printf("vm_bounce_alloc: called recursively???\n");
return;
}
if (bp->b_bufsize < bp->b_bcount) {
printf(
"vm_bounce_alloc: b_bufsize(0x%lx) < b_bcount(0x%lx) !!\n",
bp->b_bufsize, bp->b_bcount);
panic("vm_bounce_alloc");
}
/*
* This is not really necessary
* if( bp->b_bufsize != bp->b_bcount) {
* printf("size: %d, count: %d\n", bp->b_bufsize, bp->b_bcount);
* }
*/
vastart = (vm_offset_t) bp->b_data;
vaend = (vm_offset_t) bp->b_data + bp->b_bufsize;
vapstart = i386_trunc_page(vastart);
vapend = i386_round_page(vaend);
countvmpg = (vapend - vapstart) / NBPG;
/*
* if any page is above 16MB, then go into bounce-buffer mode
*/
va = vapstart;
for (i = 0; i < countvmpg; i++) {
pa = pmap_kextract(va);
if (pa >= SIXTEENMEG)
++dobounceflag;
va += NBPG;
}
if (dobounceflag == 0)
return;
if (bouncepages < dobounceflag)
panic("Not enough bounce buffers!!!");
/*
* allocate a replacement kva for b_addr
*/
kva = vm_bounce_kva(countvmpg*NBPG, 1);
#if 0
printf("%s: vapstart: %x, vapend: %x, countvmpg: %d, kva: %x ",
(bp->b_flags & B_READ) ? "read":"write",
vapstart, vapend, countvmpg, kva);
#endif
va = vapstart;
for (i = 0; i < countvmpg; i++) {
pa = pmap_kextract(va);
if (pa >= SIXTEENMEG) {
/*
* allocate a replacement page
*/
vm_offset_t bpa = vm_bounce_page_find(1);
pmap_kenter(kva + (NBPG * i), bpa);
#if 0
printf("r(%d): (%x,%x,%x) ", i, va, pa, bpa);
#endif
/*
* if we are writing, the copy the data into the page
*/
if ((bp->b_flags & B_READ) == 0) {
bcopy((caddr_t) va, (caddr_t) kva + (NBPG * i), NBPG);
}
} else {
/*
* use original page
*/
pmap_kenter(kva + (NBPG * i), pa);
}
va += NBPG;
}
/*
* flag the buffer as being bounced
*/
bp->b_flags |= B_BOUNCE;
/*
* save the original buffer kva
*/
bp->b_savekva = bp->b_data;
/*
* put our new kva into the buffer (offset by original offset)
*/
bp->b_data = (caddr_t) (((vm_offset_t) kva) |
((vm_offset_t) bp->b_savekva & (NBPG - 1)));
#if 0
printf("b_savekva: %x, newva: %x\n", bp->b_savekva, bp->b_data);
#endif
return;
}
/*
* hook into biodone to free bounce buffer
*/
void
vm_bounce_free(bp)
struct buf *bp;
{
int i;
vm_offset_t origkva, bouncekva, bouncekvaend;
/*
* if this isn't a bounced buffer, then just return
*/
if ((bp->b_flags & B_BOUNCE) == 0)
return;
/*
* This check is not necessary
* if (bp->b_bufsize != bp->b_bcount) {
* printf("vm_bounce_free: b_bufsize=%d, b_bcount=%d\n",
* bp->b_bufsize, bp->b_bcount);
* }
*/
origkva = (vm_offset_t) bp->b_savekva;
bouncekva = (vm_offset_t) bp->b_data;
/*
printf("free: %d ", bp->b_bufsize);
*/
/*
* check every page in the kva space for b_addr
*/
for (i = 0; i < bp->b_bufsize; ) {
vm_offset_t mybouncepa;
vm_offset_t copycount;
copycount = i386_round_page(bouncekva + 1) - bouncekva;
mybouncepa = pmap_kextract(i386_trunc_page(bouncekva));
/*
* if this is a bounced pa, then process as one
*/
if ( mybouncepa != pmap_kextract( i386_trunc_page( origkva))) {
vm_offset_t tocopy = copycount;
if (i + tocopy > bp->b_bufsize)
tocopy = bp->b_bufsize - i;
/*
* if this is a read, then copy from bounce buffer into original buffer
*/
if (bp->b_flags & B_READ)
bcopy((caddr_t) bouncekva, (caddr_t) origkva, tocopy);
/*
* free the bounce allocation
*/
/*
printf("(kva: %x, pa: %x)", bouncekva, mybouncepa);
*/
vm_bounce_page_free(mybouncepa, 1);
}
origkva += copycount;
bouncekva += copycount;
i += copycount;
}
/*
printf("\n");
*/
/*
* add the old kva into the "to free" list
*/
bouncekva= i386_trunc_page((vm_offset_t) bp->b_data);
bouncekvaend= i386_round_page((vm_offset_t)bp->b_data + bp->b_bufsize);
/*
printf("freeva: %d\n", (bouncekvaend - bouncekva) / NBPG);
*/
vm_bounce_kva_free( bouncekva, (bouncekvaend - bouncekva), 0);
bp->b_data = bp->b_savekva;
bp->b_savekva = 0;
bp->b_flags &= ~B_BOUNCE;
return;
}
/*
* init the bounce buffer system
*/
void
vm_bounce_init()
{
int i;
kvasfreecnt = 0;
if (bouncepages == 0)
return;
bounceallocarraysize = (bouncepages + BITS_IN_UNSIGNED - 1) / BITS_IN_UNSIGNED;
bounceallocarray = malloc(bounceallocarraysize * sizeof(unsigned), M_TEMP, M_NOWAIT);
if (!bounceallocarray)
panic("Cannot allocate bounce resource array\n");
bzero(bounceallocarray, bounceallocarraysize * sizeof(unsigned));
bouncepa = malloc(bouncepages * sizeof(vm_offset_t), M_TEMP, M_NOWAIT);
if (!bouncepa)
panic("Cannot allocate physical memory array\n");
for(i=0;i<bouncepages;i++) {
vm_offset_t pa;
if( (pa = pmap_kextract((vm_offset_t) bouncememory + i * NBPG)) >= SIXTEENMEG)
panic("bounce memory out of range");
if( pa == 0)
panic("bounce memory not resident");
bouncepa[i] = pa;
}
bouncefree = bouncepages;
}
#endif /* BOUNCE_BUFFERS */
/*
* quick version of vm_fault
*/
void
vm_fault_quick( v, prot)
vm_offset_t v;
int prot;
{
if( (cpu_class == CPUCLASS_386) &&
(prot & VM_PROT_WRITE))
vm_fault(&curproc->p_vmspace->vm_map, v,
VM_PROT_READ|VM_PROT_WRITE, FALSE);
else if( prot & VM_PROT_WRITE)
*(volatile char *)v += 0;
else
*(volatile char *)v;
}
/*
* Finish a fork operation, with process p2 nearly set up.
* Copy and update the kernel stack and pcb, making the child
* ready to run, and marking it so that it can return differently
* than the parent. Returns 1 in the child process, 0 in the parent.
* We currently double-map the user area so that the stack is at the same
* address in each process; in the future we will probably relocate
* the frame pointers on the stack after copying.
*/
int
cpu_fork(p1, p2)
register struct proc *p1, *p2;
{
register struct user *up = p2->p_addr;
int offset;
extern char kstack[];
extern int mvesp();
/*
* Copy pcb and stack from proc p1 to p2.
* We do this as cheaply as possible, copying only the active
* part of the stack. The stack and pcb need to agree;
* this is tricky, as the final pcb is constructed by savectx,
* but its frame isn't yet on the stack when the stack is copied.
* swtch compensates for this when the child eventually runs.
* This should be done differently, with a single call
* that copies and updates the pcb+stack,
* replacing the bcopy and savectx.
*/
p2->p_addr->u_pcb = p1->p_addr->u_pcb;
offset = mvesp() - (int)kstack;
bcopy((caddr_t)kstack + offset, (caddr_t)p2->p_addr + offset,
(unsigned) ctob(UPAGES) - offset);
p2->p_md.md_regs = p1->p_md.md_regs;
pmap_activate(&p2->p_vmspace->vm_pmap, &up->u_pcb);
/*
*
* Arrange for a non-local goto when the new process
* is started, to resume here, returning nonzero from setjmp.
*/
if (savectx(&up->u_pcb, 1)) {
/*
* Return 1 in child.
*/
return (1);
}
return (0);
}
void
cpu_exit(p)
register struct proc *p;
{
#if NNPX > 0
npxexit(p);
#endif /* NNPX */
curproc = p;
mi_switch();
/*
* This is to shutup the compiler, and if swtch() failed I suppose
* this would be a good thing. This keeps gcc happy because panic
* is a volatile void function as well.
*/
panic("cpu_exit");
}
void
cpu_wait(p) struct proc *p; {
/* extern vm_map_t upages_map; */
/* drop per-process resources */
pmap_remove(vm_map_pmap(kernel_map), (vm_offset_t) p->p_addr,
((vm_offset_t) p->p_addr) + ctob(UPAGES));
kmem_free(kernel_map, (vm_offset_t)p->p_addr, ctob(UPAGES));
vmspace_free(p->p_vmspace);
}
/*
* Dump the machine specific header information at the start of a core dump.
*/
int
cpu_coredump(p, vp, cred)
struct proc *p;
struct vnode *vp;
struct ucred *cred;
{
return (vn_rdwr(UIO_WRITE, vp, (caddr_t) p->p_addr, ctob(UPAGES),
(off_t)0, UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, cred, (int *)NULL,
p));
}
/*
* Set a red zone in the kernel stack after the u. area.
*/
void
setredzone(pte, vaddr)
u_short *pte;
caddr_t vaddr;
{
/* eventually do this by setting up an expand-down stack segment
for ss0: selector, allowing stack access down to top of u.
this means though that protection violations need to be handled
thru a double fault exception that must do an integral task
switch to a known good context, within which a dump can be
taken. a sensible scheme might be to save the initial context
used by sched (that has physical memory mapped 1:1 at bottom)
and take the dump while still in mapped mode */
}
/*
* Move pages from one kernel virtual address to another.
* Both addresses are assumed to reside in the Sysmap,
* and size must be a multiple of CLSIZE.
*/
void
pagemove(from, to, size)
register caddr_t from, to;
int size;
{
register vm_offset_t pa;
if (size & CLOFSET)
panic("pagemove");
while (size > 0) {
pa = pmap_kextract((vm_offset_t)from);
if (pa == 0)
panic("pagemove 2");
if (pmap_kextract((vm_offset_t)to) != 0)
panic("pagemove 3");
pmap_kremove((vm_offset_t)from);
pmap_kenter((vm_offset_t)to, pa);
from += PAGE_SIZE;
to += PAGE_SIZE;
size -= PAGE_SIZE;
}
}
/*
* Convert kernel VA to physical address
*/
u_long
kvtop(void *addr)
{
vm_offset_t va;
va = pmap_kextract((vm_offset_t)addr);
if (va == 0)
panic("kvtop: zero page frame");
return((int)va);
}
/*
* Map an IO request into kernel virtual address space.
*
* All requests are (re)mapped into kernel VA space.
* Notice that we use b_bufsize for the size of the buffer
* to be mapped. b_bcount might be modified by the driver.
*/
void
vmapbuf(bp)
register struct buf *bp;
{
register int npf;
register caddr_t addr;
int off;
vm_offset_t kva;
vm_offset_t pa, lastv, v;
if ((bp->b_flags & B_PHYS) == 0)
panic("vmapbuf");
/*
* this is the kva that is to be used for
* the temporary kernel mapping
*/
kva = (vm_offset_t) bp->b_saveaddr;
lastv = 0;
for (addr = (caddr_t)trunc_page(bp->b_data);
addr < bp->b_data + bp->b_bufsize;
addr += PAGE_SIZE) {
/*
* make sure that the pde is valid and held
*/
v = trunc_page(((vm_offset_t)vtopte(addr)));
if (v != lastv) {
vm_fault_quick(v, VM_PROT_READ);
pa = pmap_kextract( v);
vm_page_hold(PHYS_TO_VM_PAGE(pa));
lastv = v;
}
/*
* do the vm_fault if needed, do the copy-on-write thing when
* reading stuff off device into memory.
*/
vm_fault_quick(addr,
(bp->b_flags&B_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ);
pa = pmap_kextract((vm_offset_t) addr);
/*
* hold the data page
*/
vm_page_hold(PHYS_TO_VM_PAGE(pa));
}
addr = bp->b_saveaddr = bp->b_data;
off = (int)addr & PGOFSET;
npf = btoc(round_page(bp->b_bufsize + off));
bp->b_data = (caddr_t) (kva + off);
while (npf--) {
pa = pmap_kextract((vm_offset_t)addr);
if (pa == 0)
panic("vmapbuf: null page frame");
pmap_kenter(kva, trunc_page(pa));
addr += PAGE_SIZE;
kva += PAGE_SIZE;
}
}
/*
* Free the io map PTEs associated with this IO operation.
* We also invalidate the TLB entries and restore the original b_addr.
*/
void
vunmapbuf(bp)
register struct buf *bp;
{
register caddr_t addr;
vm_offset_t v,lastv,pa;
if ((bp->b_flags & B_PHYS) == 0)
panic("vunmapbuf");
for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data);
addr < bp->b_data + bp->b_bufsize;
addr += NBPG)
pmap_kremove((vm_offset_t) addr);
bp->b_data = bp->b_saveaddr;
bp->b_saveaddr = NULL;
/*
* unhold the pde, and data pages
*/
lastv = 0;
for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data);
addr < bp->b_data + bp->b_bufsize;
addr += NBPG) {
/*
* release the data page
*/
pa = pmap_kextract((vm_offset_t) addr);
vm_page_unhold(PHYS_TO_VM_PAGE(pa));
/*
* and unhold the page table
*/
v = trunc_page(((vm_offset_t)vtopte(addr)));
if (v != lastv) {
pa = pmap_kextract(v);
vm_page_unhold(PHYS_TO_VM_PAGE(pa));
lastv = v;
}
}
}
/*
* Force reset the processor by invalidating the entire address space!
*/
void
cpu_reset() {
/* force a shutdown by unmapping entire address space ! */
bzero((caddr_t) PTD, NBPG);
/* "good night, sweet prince .... <THUNK!>" */
pmap_update();
/* NOTREACHED */
while(1);
}
/*
* Grow the user stack to allow for 'sp'. This version grows the stack in
* chunks of SGROWSIZ.
*/
int
grow(p, sp)
struct proc *p;
u_int sp;
{
unsigned int nss;
caddr_t v;
struct vmspace *vm = p->p_vmspace;
if ((caddr_t)sp <= vm->vm_maxsaddr || (unsigned)sp >= (unsigned)USRSTACK)
return (1);
nss = roundup(USRSTACK - (unsigned)sp, PAGE_SIZE);
if (nss > p->p_rlimit[RLIMIT_STACK].rlim_cur)
return (0);
if (vm->vm_ssize && roundup(vm->vm_ssize << PAGE_SHIFT,
SGROWSIZ) < nss) {
int grow_amount;
/*
* If necessary, grow the VM that the stack occupies
* to allow for the rlimit. This allows us to not have
* to allocate all of the VM up-front in execve (which
* is expensive).
* Grow the VM by the amount requested rounded up to
* the nearest SGROWSIZ to provide for some hysteresis.
*/
grow_amount = roundup((nss - (vm->vm_ssize << PAGE_SHIFT)), SGROWSIZ);
v = (char *)USRSTACK - roundup(vm->vm_ssize << PAGE_SHIFT,
SGROWSIZ) - grow_amount;
/*
* If there isn't enough room to extend by SGROWSIZ, then
* just extend to the maximum size
*/
if (v < vm->vm_maxsaddr) {
v = vm->vm_maxsaddr;
grow_amount = MAXSSIZ - (vm->vm_ssize << PAGE_SHIFT);
}
if (vm_allocate(&vm->vm_map, (vm_offset_t *)&v,
grow_amount, FALSE) != KERN_SUCCESS) {
return (0);
}
vm->vm_ssize += grow_amount >> PAGE_SHIFT;
}
return (1);
}
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