freebsd-skq/sys/amd64/vmm/vmm_mem.c
grehan d45b7f14ae Import of bhyve hypervisor and utilities, part 1.
vmm.ko - kernel module for VT-x, VT-d and hypervisor control
  bhyve  - user-space sequencer and i/o emulation
  vmmctl - dump of hypervisor register state
  libvmm - front-end to vmm.ko chardev interface

bhyve was designed and implemented by Neel Natu.

Thanks to the following folk from NetApp who helped to make this available:
	Joe CaraDonna
	Peter Snyder
	Jeff Heller
	Sandeep Mann
	Steve Miller
	Brian Pawlowski
2011-05-13 04:54:01 +00:00

414 lines
10 KiB
C

/*-
* Copyright (c) 2011 NetApp, Inc.
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``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 NETAPP, INC 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.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/linker.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <machine/md_var.h>
#include <machine/metadata.h>
#include <machine/pc/bios.h>
#include <machine/vmparam.h>
#include <machine/pmap.h>
#include "vmm_util.h"
#include "vmm_mem.h"
static MALLOC_DEFINE(M_VMM_MEM, "vmm memory", "vmm memory");
#define MB (1024 * 1024)
#define GB (1024 * MB)
#define VMM_MEM_MAXSEGS 64
/* protected by vmm_mem_mtx */
static struct {
vm_paddr_t base;
vm_size_t length;
} vmm_mem_avail[VMM_MEM_MAXSEGS];
static int vmm_mem_nsegs;
static vm_paddr_t maxaddr;
static struct mtx vmm_mem_mtx;
/*
* Steal any memory that was deliberately hidden from FreeBSD either by
* the use of MAXMEM kernel config option or the hw.physmem loader tunable.
*/
static int
vmm_mem_steal_memory(void)
{
int nsegs;
caddr_t kmdp;
uint32_t smapsize;
uint64_t base, length;
struct bios_smap *smapbase, *smap, *smapend;
/*
* Borrowed from hammer_time() and getmemsize() in machdep.c
*/
kmdp = preload_search_by_type("elf kernel");
if (kmdp == NULL)
kmdp = preload_search_by_type("elf64 kernel");
smapbase = (struct bios_smap *)preload_search_info(kmdp,
MODINFO_METADATA | MODINFOMD_SMAP);
if (smapbase == NULL)
panic("No BIOS smap info from loader!");
smapsize = *((uint32_t *)smapbase - 1);
smapend = (struct bios_smap *)((uintptr_t)smapbase + smapsize);
nsegs = 0;
for (smap = smapbase; smap < smapend; smap++) {
/*
* XXX
* Assuming non-overlapping, monotonically increasing
* memory segments.
*/
if (smap->type != SMAP_TYPE_MEMORY)
continue;
if (smap->length == 0)
break;
base = roundup(smap->base, NBPDR);
length = rounddown(smap->length, NBPDR);
/* Skip this segment if FreeBSD is using all of it. */
if (base + length <= ptoa(Maxmem))
continue;
/*
* If FreeBSD is using part of this segment then adjust
* 'base' and 'length' accordingly.
*/
if (base < ptoa(Maxmem)) {
uint64_t used;
used = roundup(ptoa(Maxmem), NBPDR) - base;
base += used;
length -= used;
}
if (length == 0)
continue;
vmm_mem_avail[nsegs].base = base;
vmm_mem_avail[nsegs].length = length;
if (base + length > maxaddr)
maxaddr = base + length;
if (0 && bootverbose) {
printf("vmm_mem_populate: index %d, base 0x%0lx, "
"length %ld\n",
nsegs, vmm_mem_avail[nsegs].base,
vmm_mem_avail[nsegs].length);
}
nsegs++;
if (nsegs >= VMM_MEM_MAXSEGS) {
printf("vmm_mem_populate: maximum number of vmm memory "
"segments reached!\n");
return (ENOSPC);
}
}
vmm_mem_nsegs = nsegs;
return (0);
}
static void
vmm_mem_direct_map(vm_paddr_t start, vm_paddr_t end)
{
vm_paddr_t addr, remaining;
int pdpi, pdi, superpage_size;
pml4_entry_t *pml4p;
pdp_entry_t *pdp;
pd_entry_t *pd;
uint64_t page_attr_bits;
if (end >= NBPML4)
panic("Cannot map memory beyond %ldGB", NBPML4 / GB);
/* XXX FreeBSD 8.1 does not use 1G superpages in the direct map */
if (0 && vmm_supports_1G_pages())
superpage_size = NBPDP;
else
superpage_size = NBPDR;
/*
* Get the page directory pointer page that contains the direct
* map address mappings.
*/
pml4p = kernel_pmap->pm_pml4;
pdp = (pdp_entry_t *)PHYS_TO_DMAP(pml4p[DMPML4I] & ~PAGE_MASK);
page_attr_bits = PG_RW | PG_V | PG_PS | PG_G;
addr = start;
while (addr < end) {
remaining = end - addr;
pdpi = addr / NBPDP;
if (superpage_size == NBPDP &&
remaining >= NBPDP &&
addr % NBPDP == 0) {
/*
* If there isn't a mapping for this address then
* create one but if there is one already make sure
* it matches what we expect it to be.
*/
if (pdp[pdpi] == 0) {
pdp[pdpi] = addr | page_attr_bits;
if (0 && bootverbose) {
printf("vmm_mem_populate: mapping "
"0x%lx with 1GB page at "
"pdpi %d\n", addr, pdpi);
}
} else {
pdp_entry_t pdpe = pdp[pdpi];
if ((pdpe & ~PAGE_MASK) != addr ||
(pdpe & page_attr_bits) != page_attr_bits) {
panic("An invalid mapping 0x%016lx "
"already exists for 0x%016lx\n",
pdpe, addr);
}
}
addr += NBPDP;
} else {
if (remaining < NBPDR) {
panic("vmm_mem_populate: remaining (%ld) must "
"be greater than NBPDR (%d)\n",
remaining, NBPDR);
}
if (pdp[pdpi] == 0) {
/*
* XXX we lose this memory forever because
* we do not keep track of the virtual address
* that would be required to free this page.
*/
pd = malloc(PAGE_SIZE, M_VMM_MEM,
M_WAITOK | M_ZERO);
if ((uintptr_t)pd & PAGE_MASK) {
panic("vmm_mem_populate: page directory"
"page not aligned on %d "
"boundary\n", PAGE_SIZE);
}
pdp[pdpi] = vtophys(pd);
pdp[pdpi] |= PG_RW | PG_V | PG_U;
if (0 && bootverbose) {
printf("Creating page directory "
"at pdp index %d for 0x%016lx\n",
pdpi, addr);
}
}
pdi = (addr % NBPDP) / NBPDR;
pd = (pd_entry_t *)PHYS_TO_DMAP(pdp[pdpi] & ~PAGE_MASK);
/*
* Create a new mapping if one doesn't already exist
* or validate it if it does.
*/
if (pd[pdi] == 0) {
pd[pdi] = addr | page_attr_bits;
if (0 && bootverbose) {
printf("vmm_mem_populate: mapping "
"0x%lx with 2MB page at "
"pdpi %d, pdi %d\n",
addr, pdpi, pdi);
}
} else {
pd_entry_t pde = pd[pdi];
if ((pde & ~PAGE_MASK) != addr ||
(pde & page_attr_bits) != page_attr_bits) {
panic("An invalid mapping 0x%016lx "
"already exists for 0x%016lx\n",
pde, addr);
}
}
addr += NBPDR;
}
}
}
static int
vmm_mem_populate(void)
{
int seg, error;
vm_paddr_t start, end;
/* populate the vmm_mem_avail[] array */
error = vmm_mem_steal_memory();
if (error)
return (error);
/*
* Now map the memory that was hidden from FreeBSD in
* the direct map VA space.
*/
for (seg = 0; seg < vmm_mem_nsegs; seg++) {
start = vmm_mem_avail[seg].base;
end = start + vmm_mem_avail[seg].length;
if ((start & PDRMASK) != 0 || (end & PDRMASK) != 0) {
panic("start (0x%016lx) and end (0x%016lx) must be "
"aligned on a %dMB boundary\n",
start, end, NBPDR / MB);
}
vmm_mem_direct_map(start, end);
}
return (0);
}
int
vmm_mem_init(void)
{
int error;
mtx_init(&vmm_mem_mtx, "vmm_mem_mtx", NULL, MTX_DEF);
error = vmm_mem_populate();
if (error)
return (error);
return (0);
}
vm_paddr_t
vmm_mem_alloc(size_t size)
{
int i;
vm_paddr_t addr;
if ((size & PDRMASK) != 0) {
panic("vmm_mem_alloc: size 0x%0lx must be "
"aligned on a 0x%0x boundary\n", size, NBPDR);
}
addr = 0;
mtx_lock(&vmm_mem_mtx);
for (i = 0; i < vmm_mem_nsegs; i++) {
if (vmm_mem_avail[i].length >= size) {
addr = vmm_mem_avail[i].base;
vmm_mem_avail[i].base += size;
vmm_mem_avail[i].length -= size;
/* remove a zero length segment */
if (vmm_mem_avail[i].length == 0) {
memmove(&vmm_mem_avail[i],
&vmm_mem_avail[i + 1],
(vmm_mem_nsegs - (i + 1)) *
sizeof(vmm_mem_avail[0]));
vmm_mem_nsegs--;
}
break;
}
}
mtx_unlock(&vmm_mem_mtx);
return (addr);
}
void
vmm_mem_free(vm_paddr_t base, size_t length)
{
int i;
if ((base & PDRMASK) != 0 || (length & PDRMASK) != 0) {
panic("vmm_mem_free: base 0x%0lx and length 0x%0lx must be "
"aligned on a 0x%0x boundary\n", base, length, NBPDR);
}
mtx_lock(&vmm_mem_mtx);
for (i = 0; i < vmm_mem_nsegs; i++) {
if (vmm_mem_avail[i].base > base)
break;
}
if (vmm_mem_nsegs >= VMM_MEM_MAXSEGS)
panic("vmm_mem_free: cannot free any more segments");
/* Create a new segment at index 'i' */
memmove(&vmm_mem_avail[i + 1], &vmm_mem_avail[i],
(vmm_mem_nsegs - i) * sizeof(vmm_mem_avail[0]));
vmm_mem_avail[i].base = base;
vmm_mem_avail[i].length = length;
vmm_mem_nsegs++;
coalesce_some_more:
for (i = 0; i < vmm_mem_nsegs - 1; i++) {
if (vmm_mem_avail[i].base + vmm_mem_avail[i].length ==
vmm_mem_avail[i + 1].base) {
vmm_mem_avail[i].length += vmm_mem_avail[i + 1].length;
memmove(&vmm_mem_avail[i + 1], &vmm_mem_avail[i + 2],
(vmm_mem_nsegs - (i + 2)) * sizeof(vmm_mem_avail[0]));
vmm_mem_nsegs--;
goto coalesce_some_more;
}
}
mtx_unlock(&vmm_mem_mtx);
}
vm_paddr_t
vmm_mem_maxaddr(void)
{
return (maxaddr);
}
void
vmm_mem_dump(void)
{
int i;
vm_paddr_t base;
vm_size_t length;
mtx_lock(&vmm_mem_mtx);
for (i = 0; i < vmm_mem_nsegs; i++) {
base = vmm_mem_avail[i].base;
length = vmm_mem_avail[i].length;
printf("%-4d0x%016lx 0x%016lx\n", i, base, base + length);
}
mtx_unlock(&vmm_mem_mtx);
}