blob: 8f5159d85dc6a491fe30a654f8dc54f4f09ab2ca [file] [log] [blame]
/*
* s390 storage key device
*
* Copyright 2015 IBM Corp.
* Author(s): Jason J. Herne <jjherne@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
* directory.
*/
#include "qemu/osdep.h"
#include "qemu/units.h"
#include "hw/boards.h"
#include "hw/qdev-properties.h"
#include "hw/s390x/storage-keys.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-misc-target.h"
#include "qapi/qmp/qdict.h"
#include "qemu/error-report.h"
#include "sysemu/memory_mapping.h"
#include "exec/address-spaces.h"
#include "sysemu/kvm.h"
#include "migration/qemu-file-types.h"
#include "migration/register.h"
#define S390_SKEYS_BUFFER_SIZE (128 * KiB) /* Room for 128k storage keys */
#define S390_SKEYS_SAVE_FLAG_EOS 0x01
#define S390_SKEYS_SAVE_FLAG_SKEYS 0x02
#define S390_SKEYS_SAVE_FLAG_ERROR 0x04
S390SKeysState *s390_get_skeys_device(void)
{
S390SKeysState *ss;
ss = S390_SKEYS(object_resolve_path_type("", TYPE_S390_SKEYS, NULL));
assert(ss);
return ss;
}
void s390_skeys_init(void)
{
Object *obj;
if (kvm_enabled()) {
obj = object_new(TYPE_KVM_S390_SKEYS);
} else {
obj = object_new(TYPE_QEMU_S390_SKEYS);
}
object_property_add_child(qdev_get_machine(), TYPE_S390_SKEYS,
obj);
object_unref(obj);
qdev_realize(DEVICE(obj), NULL, &error_fatal);
}
static void write_keys(FILE *f, uint8_t *keys, uint64_t startgfn,
uint64_t count, Error **errp)
{
uint64_t curpage = startgfn;
uint64_t maxpage = curpage + count - 1;
for (; curpage <= maxpage; curpage++) {
uint8_t acc = (*keys & 0xF0) >> 4;
int fp = (*keys & 0x08);
int ref = (*keys & 0x04);
int ch = (*keys & 0x02);
int res = (*keys & 0x01);
fprintf(f, "page=%03" PRIx64 ": key(%d) => ACC=%X, FP=%d, REF=%d,"
" ch=%d, reserved=%d\n",
curpage, *keys, acc, fp, ref, ch, res);
keys++;
}
}
void hmp_info_skeys(Monitor *mon, const QDict *qdict)
{
S390SKeysState *ss = s390_get_skeys_device();
S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
uint64_t addr = qdict_get_int(qdict, "addr");
uint8_t key;
int r;
/* Quick check to see if guest is using storage keys*/
if (!skeyclass->skeys_are_enabled(ss)) {
monitor_printf(mon, "Error: This guest is not using storage keys\n");
return;
}
if (!address_space_access_valid(&address_space_memory,
addr & TARGET_PAGE_MASK, TARGET_PAGE_SIZE,
false, MEMTXATTRS_UNSPECIFIED)) {
monitor_printf(mon, "Error: The given address is not valid\n");
return;
}
r = skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key);
if (r < 0) {
monitor_printf(mon, "Error: %s\n", strerror(-r));
return;
}
monitor_printf(mon, " key: 0x%X\n", key);
}
void hmp_dump_skeys(Monitor *mon, const QDict *qdict)
{
const char *filename = qdict_get_str(qdict, "filename");
Error *err = NULL;
qmp_dump_skeys(filename, &err);
if (err) {
error_report_err(err);
}
}
void qmp_dump_skeys(const char *filename, Error **errp)
{
S390SKeysState *ss = s390_get_skeys_device();
S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
GuestPhysBlockList guest_phys_blocks;
GuestPhysBlock *block;
uint64_t pages, gfn;
Error *lerr = NULL;
uint8_t *buf;
int ret;
int fd;
FILE *f;
/* Quick check to see if guest is using storage keys*/
if (!skeyclass->skeys_are_enabled(ss)) {
error_setg(errp, "This guest is not using storage keys - "
"nothing to dump");
return;
}
fd = qemu_open_old(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
if (fd < 0) {
error_setg_file_open(errp, errno, filename);
return;
}
f = fdopen(fd, "wb");
if (!f) {
close(fd);
error_setg_file_open(errp, errno, filename);
return;
}
buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
if (!buf) {
error_setg(errp, "Could not allocate memory");
goto out;
}
assert(qemu_mutex_iothread_locked());
guest_phys_blocks_init(&guest_phys_blocks);
guest_phys_blocks_append(&guest_phys_blocks);
QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) {
assert(QEMU_IS_ALIGNED(block->target_start, TARGET_PAGE_SIZE));
assert(QEMU_IS_ALIGNED(block->target_end, TARGET_PAGE_SIZE));
gfn = block->target_start / TARGET_PAGE_SIZE;
pages = (block->target_end - block->target_start) / TARGET_PAGE_SIZE;
while (pages) {
const uint64_t cur_pages = MIN(pages, S390_SKEYS_BUFFER_SIZE);
ret = skeyclass->get_skeys(ss, gfn, cur_pages, buf);
if (ret < 0) {
error_setg_errno(errp, -ret, "get_keys error");
goto out_free;
}
/* write keys to stream */
write_keys(f, buf, gfn, cur_pages, &lerr);
if (lerr) {
goto out_free;
}
gfn += cur_pages;
pages -= cur_pages;
}
}
out_free:
guest_phys_blocks_free(&guest_phys_blocks);
error_propagate(errp, lerr);
g_free(buf);
out:
fclose(f);
}
static bool qemu_s390_skeys_are_enabled(S390SKeysState *ss)
{
QEMUS390SKeysState *skeys = QEMU_S390_SKEYS(ss);
/* Lockless check is sufficient. */
return !!skeys->keydata;
}
static bool qemu_s390_enable_skeys(S390SKeysState *ss)
{
QEMUS390SKeysState *skeys = QEMU_S390_SKEYS(ss);
static gsize initialized;
if (likely(skeys->keydata)) {
return true;
}
/*
* TODO: Modern Linux doesn't use storage keys unless running KVM guests
* that use storage keys. Therefore, we keep it simple for now.
*
* 1) We should initialize to "referenced+changed" for an initial
* over-indication. Let's avoid touching megabytes of data for now and
* assume that any sane user will issue a storage key instruction before
* actually relying on this data.
* 2) Relying on ram_size and allocating a big array is ugly. We should
* allocate and manage storage key data per RAMBlock or optimally using
* some sparse data structure.
* 3) We only ever have a single S390SKeysState, so relying on
* g_once_init_enter() is good enough.
*/
if (g_once_init_enter(&initialized)) {
MachineState *machine = MACHINE(qdev_get_machine());
skeys->key_count = machine->ram_size / TARGET_PAGE_SIZE;
skeys->keydata = g_malloc0(skeys->key_count);
g_once_init_leave(&initialized, 1);
}
return false;
}
static int qemu_s390_skeys_set(S390SKeysState *ss, uint64_t start_gfn,
uint64_t count, uint8_t *keys)
{
QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss);
int i;
/* Check for uint64 overflow and access beyond end of key data */
if (unlikely(!skeydev->keydata || start_gfn + count > skeydev->key_count ||
start_gfn + count < count)) {
error_report("Error: Setting storage keys for pages with unallocated "
"storage key memory: gfn=%" PRIx64 " count=%" PRId64,
start_gfn, count);
return -EINVAL;
}
for (i = 0; i < count; i++) {
skeydev->keydata[start_gfn + i] = keys[i];
}
return 0;
}
static int qemu_s390_skeys_get(S390SKeysState *ss, uint64_t start_gfn,
uint64_t count, uint8_t *keys)
{
QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss);
int i;
/* Check for uint64 overflow and access beyond end of key data */
if (unlikely(!skeydev->keydata || start_gfn + count > skeydev->key_count ||
start_gfn + count < count)) {
error_report("Error: Getting storage keys for pages with unallocated "
"storage key memory: gfn=%" PRIx64 " count=%" PRId64,
start_gfn, count);
return -EINVAL;
}
for (i = 0; i < count; i++) {
keys[i] = skeydev->keydata[start_gfn + i];
}
return 0;
}
static void qemu_s390_skeys_class_init(ObjectClass *oc, void *data)
{
S390SKeysClass *skeyclass = S390_SKEYS_CLASS(oc);
DeviceClass *dc = DEVICE_CLASS(oc);
skeyclass->skeys_are_enabled = qemu_s390_skeys_are_enabled;
skeyclass->enable_skeys = qemu_s390_enable_skeys;
skeyclass->get_skeys = qemu_s390_skeys_get;
skeyclass->set_skeys = qemu_s390_skeys_set;
/* Reason: Internal device (only one skeys device for the whole memory) */
dc->user_creatable = false;
}
static const TypeInfo qemu_s390_skeys_info = {
.name = TYPE_QEMU_S390_SKEYS,
.parent = TYPE_S390_SKEYS,
.instance_size = sizeof(QEMUS390SKeysState),
.class_init = qemu_s390_skeys_class_init,
.class_size = sizeof(S390SKeysClass),
};
static void s390_storage_keys_save(QEMUFile *f, void *opaque)
{
S390SKeysState *ss = S390_SKEYS(opaque);
S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
GuestPhysBlockList guest_phys_blocks;
GuestPhysBlock *block;
uint64_t pages, gfn;
int error = 0;
uint8_t *buf;
if (!skeyclass->skeys_are_enabled(ss)) {
goto end_stream;
}
buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
if (!buf) {
error_report("storage key save could not allocate memory");
goto end_stream;
}
guest_phys_blocks_init(&guest_phys_blocks);
guest_phys_blocks_append(&guest_phys_blocks);
/* Send each contiguous physical memory range separately. */
QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) {
assert(QEMU_IS_ALIGNED(block->target_start, TARGET_PAGE_SIZE));
assert(QEMU_IS_ALIGNED(block->target_end, TARGET_PAGE_SIZE));
gfn = block->target_start / TARGET_PAGE_SIZE;
pages = (block->target_end - block->target_start) / TARGET_PAGE_SIZE;
qemu_put_be64(f, block->target_start | S390_SKEYS_SAVE_FLAG_SKEYS);
qemu_put_be64(f, pages);
while (pages) {
const uint64_t cur_pages = MIN(pages, S390_SKEYS_BUFFER_SIZE);
if (!error) {
error = skeyclass->get_skeys(ss, gfn, cur_pages, buf);
if (error) {
/*
* Create a valid stream with all 0x00 and indicate
* S390_SKEYS_SAVE_FLAG_ERROR to the destination.
*/
error_report("S390_GET_KEYS error %d", error);
memset(buf, 0, S390_SKEYS_BUFFER_SIZE);
}
}
qemu_put_buffer(f, buf, cur_pages);
gfn += cur_pages;
pages -= cur_pages;
}
if (error) {
break;
}
}
guest_phys_blocks_free(&guest_phys_blocks);
g_free(buf);
end_stream:
if (error) {
qemu_put_be64(f, S390_SKEYS_SAVE_FLAG_ERROR);
} else {
qemu_put_be64(f, S390_SKEYS_SAVE_FLAG_EOS);
}
}
static int s390_storage_keys_load(QEMUFile *f, void *opaque, int version_id)
{
S390SKeysState *ss = S390_SKEYS(opaque);
S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
int ret = 0;
/*
* Make sure to lazy-enable if required to be done explicitly. No need to
* flush any TLB as the VM is not running yet.
*/
if (skeyclass->enable_skeys) {
skeyclass->enable_skeys(ss);
}
while (!ret) {
ram_addr_t addr;
int flags;
addr = qemu_get_be64(f);
flags = addr & ~TARGET_PAGE_MASK;
addr &= TARGET_PAGE_MASK;
switch (flags) {
case S390_SKEYS_SAVE_FLAG_SKEYS: {
const uint64_t total_count = qemu_get_be64(f);
uint64_t handled_count = 0, cur_count;
uint64_t cur_gfn = addr / TARGET_PAGE_SIZE;
uint8_t *buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
if (!buf) {
error_report("storage key load could not allocate memory");
ret = -ENOMEM;
break;
}
while (handled_count < total_count) {
cur_count = MIN(total_count - handled_count,
S390_SKEYS_BUFFER_SIZE);
qemu_get_buffer(f, buf, cur_count);
ret = skeyclass->set_skeys(ss, cur_gfn, cur_count, buf);
if (ret < 0) {
error_report("S390_SET_KEYS error %d", ret);
break;
}
handled_count += cur_count;
cur_gfn += cur_count;
}
g_free(buf);
break;
}
case S390_SKEYS_SAVE_FLAG_ERROR: {
error_report("Storage key data is incomplete");
ret = -EINVAL;
break;
}
case S390_SKEYS_SAVE_FLAG_EOS:
/* normal exit */
return 0;
default:
error_report("Unexpected storage key flag data: %#x", flags);
ret = -EINVAL;
}
}
return ret;
}
static SaveVMHandlers savevm_s390_storage_keys = {
.save_state = s390_storage_keys_save,
.load_state = s390_storage_keys_load,
};
static void s390_skeys_realize(DeviceState *dev, Error **errp)
{
S390SKeysState *ss = S390_SKEYS(dev);
if (ss->migration_enabled) {
register_savevm_live(TYPE_S390_SKEYS, 0, 1,
&savevm_s390_storage_keys, ss);
}
}
static Property s390_skeys_props[] = {
DEFINE_PROP_BOOL("migration-enabled", S390SKeysState, migration_enabled, true),
DEFINE_PROP_END_OF_LIST(),
};
static void s390_skeys_class_init(ObjectClass *oc, void *data)
{
DeviceClass *dc = DEVICE_CLASS(oc);
dc->hotpluggable = false;
dc->realize = s390_skeys_realize;
device_class_set_props(dc, s390_skeys_props);
set_bit(DEVICE_CATEGORY_MISC, dc->categories);
}
static const TypeInfo s390_skeys_info = {
.name = TYPE_S390_SKEYS,
.parent = TYPE_DEVICE,
.instance_size = sizeof(S390SKeysState),
.class_init = s390_skeys_class_init,
.class_size = sizeof(S390SKeysClass),
.abstract = true,
};
static void qemu_s390_skeys_register_types(void)
{
type_register_static(&s390_skeys_info);
type_register_static(&qemu_s390_skeys_info);
}
type_init(qemu_s390_skeys_register_types)