1/*
2 * s390 storage key device
3 *
4 * Copyright 2015 IBM Corp.
5 * Author(s): Jason J. Herne <jjherne@linux.vnet.ibm.com>
6 *
7 * This work is licensed under the terms of the GNU GPL, version 2 or (at
8 * your option) any later version. See the COPYING file in the top-level
9 * directory.
10 */
11
12#include "qemu/osdep.h"
13#include "qemu/units.h"
14#include "hw/boards.h"
15#include "hw/s390x/storage-keys.h"
16#include "qapi/error.h"
17#include "qapi/qapi-commands-misc-target.h"
18#include "qapi/qmp/qdict.h"
19#include "qemu/error-report.h"
20#include "sysemu/kvm.h"
21#include "migration/qemu-file-types.h"
22#include "migration/register.h"
23
24#define S390_SKEYS_BUFFER_SIZE (128 * KiB) /* Room for 128k storage keys */
25#define S390_SKEYS_SAVE_FLAG_EOS 0x01
26#define S390_SKEYS_SAVE_FLAG_SKEYS 0x02
27#define S390_SKEYS_SAVE_FLAG_ERROR 0x04
28
29S390SKeysState *s390_get_skeys_device(void)
30{
31 S390SKeysState *ss;
32
33 ss = S390_SKEYS(object_resolve_path_type("", TYPE_S390_SKEYS, NULL));
34 assert(ss);
35 return ss;
36}
37
38void s390_skeys_init(void)
39{
40 Object *obj;
41
42 if (kvm_enabled()) {
43 obj = object_new(TYPE_KVM_S390_SKEYS);
44 } else {
45 obj = object_new(TYPE_QEMU_S390_SKEYS);
46 }
47 object_property_add_child(qdev_get_machine(), TYPE_S390_SKEYS,
48 obj, NULL);
49 object_unref(obj);
50
51 qdev_init_nofail(DEVICE(obj));
52}
53
54static void write_keys(FILE *f, uint8_t *keys, uint64_t startgfn,
55 uint64_t count, Error **errp)
56{
57 uint64_t curpage = startgfn;
58 uint64_t maxpage = curpage + count - 1;
59
60 for (; curpage <= maxpage; curpage++) {
61 uint8_t acc = (*keys & 0xF0) >> 4;
62 int fp = (*keys & 0x08);
63 int ref = (*keys & 0x04);
64 int ch = (*keys & 0x02);
65 int res = (*keys & 0x01);
66
67 fprintf(f, "page=%03" PRIx64 ": key(%d) => ACC=%X, FP=%d, REF=%d,"
68 " ch=%d, reserved=%d\n",
69 curpage, *keys, acc, fp, ref, ch, res);
70 keys++;
71 }
72}
73
74void hmp_info_skeys(Monitor *mon, const QDict *qdict)
75{
76 S390SKeysState *ss = s390_get_skeys_device();
77 S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
78 uint64_t addr = qdict_get_int(qdict, "addr");
79 uint8_t key;
80 int r;
81
82 /* Quick check to see if guest is using storage keys*/
83 if (!skeyclass->skeys_enabled(ss)) {
84 monitor_printf(mon, "Error: This guest is not using storage keys\n");
85 return;
86 }
87
88 r = skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key);
89 if (r < 0) {
90 monitor_printf(mon, "Error: %s\n", strerror(-r));
91 return;
92 }
93
94 monitor_printf(mon, " key: 0x%X\n", key);
95}
96
97void hmp_dump_skeys(Monitor *mon, const QDict *qdict)
98{
99 const char *filename = qdict_get_str(qdict, "filename");
100 Error *err = NULL;
101
102 qmp_dump_skeys(filename, &err);
103 if (err) {
104 error_report_err(err);
105 }
106}
107
108void qmp_dump_skeys(const char *filename, Error **errp)
109{
110 S390SKeysState *ss = s390_get_skeys_device();
111 S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
112 const uint64_t total_count = ram_size / TARGET_PAGE_SIZE;
113 uint64_t handled_count = 0, cur_count;
114 Error *lerr = NULL;
115 vaddr cur_gfn = 0;
116 uint8_t *buf;
117 int ret;
118 int fd;
119 FILE *f;
120
121 /* Quick check to see if guest is using storage keys*/
122 if (!skeyclass->skeys_enabled(ss)) {
123 error_setg(errp, "This guest is not using storage keys - "
124 "nothing to dump");
125 return;
126 }
127
128 fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
129 if (fd < 0) {
130 error_setg_file_open(errp, errno, filename);
131 return;
132 }
133 f = fdopen(fd, "wb");
134 if (!f) {
135 close(fd);
136 error_setg_file_open(errp, errno, filename);
137 return;
138 }
139
140 buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
141 if (!buf) {
142 error_setg(errp, "Could not allocate memory");
143 goto out;
144 }
145
146 /* we'll only dump initial memory for now */
147 while (handled_count < total_count) {
148 /* Calculate how many keys to ask for & handle overflow case */
149 cur_count = MIN(total_count - handled_count, S390_SKEYS_BUFFER_SIZE);
150
151 ret = skeyclass->get_skeys(ss, cur_gfn, cur_count, buf);
152 if (ret < 0) {
153 error_setg(errp, "get_keys error %d", ret);
154 goto out_free;
155 }
156
157 /* write keys to stream */
158 write_keys(f, buf, cur_gfn, cur_count, &lerr);
159 if (lerr) {
160 goto out_free;
161 }
162
163 cur_gfn += cur_count;
164 handled_count += cur_count;
165 }
166
167out_free:
168 error_propagate(errp, lerr);
169 g_free(buf);
170out:
171 fclose(f);
172}
173
174static void qemu_s390_skeys_init(Object *obj)
175{
176 QEMUS390SKeysState *skeys = QEMU_S390_SKEYS(obj);
177 MachineState *machine = MACHINE(qdev_get_machine());
178
179 skeys->key_count = machine->maxram_size / TARGET_PAGE_SIZE;
180 skeys->keydata = g_malloc0(skeys->key_count);
181}
182
183static int qemu_s390_skeys_enabled(S390SKeysState *ss)
184{
185 return 1;
186}
187
188/*
189 * TODO: for memory hotplug support qemu_s390_skeys_set and qemu_s390_skeys_get
190 * will have to make sure that the given gfn belongs to a memory region and not
191 * a memory hole.
192 */
193static int qemu_s390_skeys_set(S390SKeysState *ss, uint64_t start_gfn,
194 uint64_t count, uint8_t *keys)
195{
196 QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss);
197 int i;
198
199 /* Check for uint64 overflow and access beyond end of key data */
200 if (start_gfn + count > skeydev->key_count || start_gfn + count < count) {
201 error_report("Error: Setting storage keys for page beyond the end "
202 "of memory: gfn=%" PRIx64 " count=%" PRId64,
203 start_gfn, count);
204 return -EINVAL;
205 }
206
207 for (i = 0; i < count; i++) {
208 skeydev->keydata[start_gfn + i] = keys[i];
209 }
210 return 0;
211}
212
213static int qemu_s390_skeys_get(S390SKeysState *ss, uint64_t start_gfn,
214 uint64_t count, uint8_t *keys)
215{
216 QEMUS390SKeysState *skeydev = QEMU_S390_SKEYS(ss);
217 int i;
218
219 /* Check for uint64 overflow and access beyond end of key data */
220 if (start_gfn + count > skeydev->key_count || start_gfn + count < count) {
221 error_report("Error: Getting storage keys for page beyond the end "
222 "of memory: gfn=%" PRIx64 " count=%" PRId64,
223 start_gfn, count);
224 return -EINVAL;
225 }
226
227 for (i = 0; i < count; i++) {
228 keys[i] = skeydev->keydata[start_gfn + i];
229 }
230 return 0;
231}
232
233static void qemu_s390_skeys_class_init(ObjectClass *oc, void *data)
234{
235 S390SKeysClass *skeyclass = S390_SKEYS_CLASS(oc);
236 DeviceClass *dc = DEVICE_CLASS(oc);
237
238 skeyclass->skeys_enabled = qemu_s390_skeys_enabled;
239 skeyclass->get_skeys = qemu_s390_skeys_get;
240 skeyclass->set_skeys = qemu_s390_skeys_set;
241
242 /* Reason: Internal device (only one skeys device for the whole memory) */
243 dc->user_creatable = false;
244}
245
246static const TypeInfo qemu_s390_skeys_info = {
247 .name = TYPE_QEMU_S390_SKEYS,
248 .parent = TYPE_S390_SKEYS,
249 .instance_init = qemu_s390_skeys_init,
250 .instance_size = sizeof(QEMUS390SKeysState),
251 .class_init = qemu_s390_skeys_class_init,
252 .class_size = sizeof(S390SKeysClass),
253};
254
255static void s390_storage_keys_save(QEMUFile *f, void *opaque)
256{
257 S390SKeysState *ss = S390_SKEYS(opaque);
258 S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
259 uint64_t pages_left = ram_size / TARGET_PAGE_SIZE;
260 uint64_t read_count, eos = S390_SKEYS_SAVE_FLAG_EOS;
261 vaddr cur_gfn = 0;
262 int error = 0;
263 uint8_t *buf;
264
265 if (!skeyclass->skeys_enabled(ss)) {
266 goto end_stream;
267 }
268
269 buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
270 if (!buf) {
271 error_report("storage key save could not allocate memory");
272 goto end_stream;
273 }
274
275 /* We only support initial memory. Standby memory is not handled yet. */
276 qemu_put_be64(f, (cur_gfn * TARGET_PAGE_SIZE) | S390_SKEYS_SAVE_FLAG_SKEYS);
277 qemu_put_be64(f, pages_left);
278
279 while (pages_left) {
280 read_count = MIN(pages_left, S390_SKEYS_BUFFER_SIZE);
281
282 if (!error) {
283 error = skeyclass->get_skeys(ss, cur_gfn, read_count, buf);
284 if (error) {
285 /*
286 * If error: we want to fill the stream with valid data instead
287 * of stopping early so we pad the stream with 0x00 values and
288 * use S390_SKEYS_SAVE_FLAG_ERROR to indicate failure to the
289 * reading side.
290 */
291 error_report("S390_GET_KEYS error %d", error);
292 memset(buf, 0, S390_SKEYS_BUFFER_SIZE);
293 eos = S390_SKEYS_SAVE_FLAG_ERROR;
294 }
295 }
296
297 qemu_put_buffer(f, buf, read_count);
298 cur_gfn += read_count;
299 pages_left -= read_count;
300 }
301
302 g_free(buf);
303end_stream:
304 qemu_put_be64(f, eos);
305}
306
307static int s390_storage_keys_load(QEMUFile *f, void *opaque, int version_id)
308{
309 S390SKeysState *ss = S390_SKEYS(opaque);
310 S390SKeysClass *skeyclass = S390_SKEYS_GET_CLASS(ss);
311 int ret = 0;
312
313 while (!ret) {
314 ram_addr_t addr;
315 int flags;
316
317 addr = qemu_get_be64(f);
318 flags = addr & ~TARGET_PAGE_MASK;
319 addr &= TARGET_PAGE_MASK;
320
321 switch (flags) {
322 case S390_SKEYS_SAVE_FLAG_SKEYS: {
323 const uint64_t total_count = qemu_get_be64(f);
324 uint64_t handled_count = 0, cur_count;
325 uint64_t cur_gfn = addr / TARGET_PAGE_SIZE;
326 uint8_t *buf = g_try_malloc(S390_SKEYS_BUFFER_SIZE);
327
328 if (!buf) {
329 error_report("storage key load could not allocate memory");
330 ret = -ENOMEM;
331 break;
332 }
333
334 while (handled_count < total_count) {
335 cur_count = MIN(total_count - handled_count,
336 S390_SKEYS_BUFFER_SIZE);
337 qemu_get_buffer(f, buf, cur_count);
338
339 ret = skeyclass->set_skeys(ss, cur_gfn, cur_count, buf);
340 if (ret < 0) {
341 error_report("S390_SET_KEYS error %d", ret);
342 break;
343 }
344 handled_count += cur_count;
345 cur_gfn += cur_count;
346 }
347 g_free(buf);
348 break;
349 }
350 case S390_SKEYS_SAVE_FLAG_ERROR: {
351 error_report("Storage key data is incomplete");
352 ret = -EINVAL;
353 break;
354 }
355 case S390_SKEYS_SAVE_FLAG_EOS:
356 /* normal exit */
357 return 0;
358 default:
359 error_report("Unexpected storage key flag data: %#x", flags);
360 ret = -EINVAL;
361 }
362 }
363
364 return ret;
365}
366
367static inline bool s390_skeys_get_migration_enabled(Object *obj, Error **errp)
368{
369 S390SKeysState *ss = S390_SKEYS(obj);
370
371 return ss->migration_enabled;
372}
373
374static SaveVMHandlers savevm_s390_storage_keys = {
375 .save_state = s390_storage_keys_save,
376 .load_state = s390_storage_keys_load,
377};
378
379static inline void s390_skeys_set_migration_enabled(Object *obj, bool value,
380 Error **errp)
381{
382 S390SKeysState *ss = S390_SKEYS(obj);
383
384 /* Prevent double registration of savevm handler */
385 if (ss->migration_enabled == value) {
386 return;
387 }
388
389 ss->migration_enabled = value;
390
391 if (ss->migration_enabled) {
392 register_savevm_live(NULL, TYPE_S390_SKEYS, 0, 1,
393 &savevm_s390_storage_keys, ss);
394 } else {
395 unregister_savevm(DEVICE(ss), TYPE_S390_SKEYS, ss);
396 }
397}
398
399static void s390_skeys_instance_init(Object *obj)
400{
401 object_property_add_bool(obj, "migration-enabled",
402 s390_skeys_get_migration_enabled,
403 s390_skeys_set_migration_enabled, NULL);
404 object_property_set_bool(obj, true, "migration-enabled", NULL);
405}
406
407static void s390_skeys_class_init(ObjectClass *oc, void *data)
408{
409 DeviceClass *dc = DEVICE_CLASS(oc);
410
411 dc->hotpluggable = false;
412 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
413}
414
415static const TypeInfo s390_skeys_info = {
416 .name = TYPE_S390_SKEYS,
417 .parent = TYPE_DEVICE,
418 .instance_init = s390_skeys_instance_init,
419 .instance_size = sizeof(S390SKeysState),
420 .class_init = s390_skeys_class_init,
421 .class_size = sizeof(S390SKeysClass),
422 .abstract = true,
423};
424
425static void qemu_s390_skeys_register_types(void)
426{
427 type_register_static(&s390_skeys_info);
428 type_register_static(&qemu_s390_skeys_info);
429}
430
431type_init(qemu_s390_skeys_register_types)
432