target/microblaze: Fix width of PC and BTARGET
[qemu.git] / migration / multifd-zlib.c
1 /*
2 * Multifd zlib compression implementation
3 *
4 * Copyright (c) 2020 Red Hat Inc
5 *
6 * Authors:
7 * Juan Quintela <quintela@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
11 */
12
13 #include "qemu/osdep.h"
14 #include <zlib.h>
15 #include "qemu/rcu.h"
16 #include "exec/target_page.h"
17 #include "qapi/error.h"
18 #include "migration.h"
19 #include "trace.h"
20 #include "multifd.h"
21
22 struct zlib_data {
23 /* stream for compression */
24 z_stream zs;
25 /* compressed buffer */
26 uint8_t *zbuff;
27 /* size of compressed buffer */
28 uint32_t zbuff_len;
29 };
30
31 /* Multifd zlib compression */
32
33 /**
34 * zlib_send_setup: setup send side
35 *
36 * Setup each channel with zlib compression.
37 *
38 * Returns 0 for success or -1 for error
39 *
40 * @p: Params for the channel that we are using
41 * @errp: pointer to an error
42 */
43 static int zlib_send_setup(MultiFDSendParams *p, Error **errp)
44 {
45 uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
46 struct zlib_data *z = g_malloc0(sizeof(struct zlib_data));
47 z_stream *zs = &z->zs;
48
49 zs->zalloc = Z_NULL;
50 zs->zfree = Z_NULL;
51 zs->opaque = Z_NULL;
52 if (deflateInit(zs, migrate_multifd_zlib_level()) != Z_OK) {
53 g_free(z);
54 error_setg(errp, "multifd %d: deflate init failed", p->id);
55 return -1;
56 }
57 /* We will never have more than page_count pages */
58 z->zbuff_len = page_count * qemu_target_page_size();
59 z->zbuff_len *= 2;
60 z->zbuff = g_try_malloc(z->zbuff_len);
61 if (!z->zbuff) {
62 deflateEnd(&z->zs);
63 g_free(z);
64 error_setg(errp, "multifd %d: out of memory for zbuff", p->id);
65 return -1;
66 }
67 p->data = z;
68 return 0;
69 }
70
71 /**
72 * zlib_send_cleanup: cleanup send side
73 *
74 * Close the channel and return memory.
75 *
76 * @p: Params for the channel that we are using
77 */
78 static void zlib_send_cleanup(MultiFDSendParams *p, Error **errp)
79 {
80 struct zlib_data *z = p->data;
81
82 deflateEnd(&z->zs);
83 g_free(z->zbuff);
84 z->zbuff = NULL;
85 g_free(p->data);
86 p->data = NULL;
87 }
88
89 /**
90 * zlib_send_prepare: prepare date to be able to send
91 *
92 * Create a compressed buffer with all the pages that we are going to
93 * send.
94 *
95 * Returns 0 for success or -1 for error
96 *
97 * @p: Params for the channel that we are using
98 * @used: number of pages used
99 */
100 static int zlib_send_prepare(MultiFDSendParams *p, uint32_t used, Error **errp)
101 {
102 struct iovec *iov = p->pages->iov;
103 struct zlib_data *z = p->data;
104 z_stream *zs = &z->zs;
105 uint32_t out_size = 0;
106 int ret;
107 uint32_t i;
108
109 for (i = 0; i < used; i++) {
110 uint32_t available = z->zbuff_len - out_size;
111 int flush = Z_NO_FLUSH;
112
113 if (i == used - 1) {
114 flush = Z_SYNC_FLUSH;
115 }
116
117 zs->avail_in = iov[i].iov_len;
118 zs->next_in = iov[i].iov_base;
119
120 zs->avail_out = available;
121 zs->next_out = z->zbuff + out_size;
122
123 /*
124 * Welcome to deflate semantics
125 *
126 * We need to loop while:
127 * - return is Z_OK
128 * - there are stuff to be compressed
129 * - there are output space free
130 */
131 do {
132 ret = deflate(zs, flush);
133 } while (ret == Z_OK && zs->avail_in && zs->avail_out);
134 if (ret == Z_OK && zs->avail_in) {
135 error_setg(errp, "multifd %d: deflate failed to compress all input",
136 p->id);
137 return -1;
138 }
139 if (ret != Z_OK) {
140 error_setg(errp, "multifd %d: deflate returned %d instead of Z_OK",
141 p->id, ret);
142 return -1;
143 }
144 out_size += available - zs->avail_out;
145 }
146 p->next_packet_size = out_size;
147 p->flags |= MULTIFD_FLAG_ZLIB;
148
149 return 0;
150 }
151
152 /**
153 * zlib_send_write: do the actual write of the data
154 *
155 * Do the actual write of the comprresed buffer.
156 *
157 * Returns 0 for success or -1 for error
158 *
159 * @p: Params for the channel that we are using
160 * @used: number of pages used
161 * @errp: pointer to an error
162 */
163 static int zlib_send_write(MultiFDSendParams *p, uint32_t used, Error **errp)
164 {
165 struct zlib_data *z = p->data;
166
167 return qio_channel_write_all(p->c, (void *)z->zbuff, p->next_packet_size,
168 errp);
169 }
170
171 /**
172 * zlib_recv_setup: setup receive side
173 *
174 * Create the compressed channel and buffer.
175 *
176 * Returns 0 for success or -1 for error
177 *
178 * @p: Params for the channel that we are using
179 * @errp: pointer to an error
180 */
181 static int zlib_recv_setup(MultiFDRecvParams *p, Error **errp)
182 {
183 uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
184 struct zlib_data *z = g_malloc0(sizeof(struct zlib_data));
185 z_stream *zs = &z->zs;
186
187 p->data = z;
188 zs->zalloc = Z_NULL;
189 zs->zfree = Z_NULL;
190 zs->opaque = Z_NULL;
191 zs->avail_in = 0;
192 zs->next_in = Z_NULL;
193 if (inflateInit(zs) != Z_OK) {
194 error_setg(errp, "multifd %d: inflate init failed", p->id);
195 return -1;
196 }
197 /* We will never have more than page_count pages */
198 z->zbuff_len = page_count * qemu_target_page_size();
199 /* We know compression "could" use more space */
200 z->zbuff_len *= 2;
201 z->zbuff = g_try_malloc(z->zbuff_len);
202 if (!z->zbuff) {
203 inflateEnd(zs);
204 error_setg(errp, "multifd %d: out of memory for zbuff", p->id);
205 return -1;
206 }
207 return 0;
208 }
209
210 /**
211 * zlib_recv_cleanup: setup receive side
212 *
213 * For no compression this function does nothing.
214 *
215 * @p: Params for the channel that we are using
216 */
217 static void zlib_recv_cleanup(MultiFDRecvParams *p)
218 {
219 struct zlib_data *z = p->data;
220
221 inflateEnd(&z->zs);
222 g_free(z->zbuff);
223 z->zbuff = NULL;
224 g_free(p->data);
225 p->data = NULL;
226 }
227
228 /**
229 * zlib_recv_pages: read the data from the channel into actual pages
230 *
231 * Read the compressed buffer, and uncompress it into the actual
232 * pages.
233 *
234 * Returns 0 for success or -1 for error
235 *
236 * @p: Params for the channel that we are using
237 * @used: number of pages used
238 * @errp: pointer to an error
239 */
240 static int zlib_recv_pages(MultiFDRecvParams *p, uint32_t used, Error **errp)
241 {
242 struct zlib_data *z = p->data;
243 z_stream *zs = &z->zs;
244 uint32_t in_size = p->next_packet_size;
245 /* we measure the change of total_out */
246 uint32_t out_size = zs->total_out;
247 uint32_t expected_size = used * qemu_target_page_size();
248 uint32_t flags = p->flags & MULTIFD_FLAG_COMPRESSION_MASK;
249 int ret;
250 int i;
251
252 if (flags != MULTIFD_FLAG_ZLIB) {
253 error_setg(errp, "multifd %d: flags received %x flags expected %x",
254 p->id, flags, MULTIFD_FLAG_ZLIB);
255 return -1;
256 }
257 ret = qio_channel_read_all(p->c, (void *)z->zbuff, in_size, errp);
258
259 if (ret != 0) {
260 return ret;
261 }
262
263 zs->avail_in = in_size;
264 zs->next_in = z->zbuff;
265
266 for (i = 0; i < used; i++) {
267 struct iovec *iov = &p->pages->iov[i];
268 int flush = Z_NO_FLUSH;
269 unsigned long start = zs->total_out;
270
271 if (i == used - 1) {
272 flush = Z_SYNC_FLUSH;
273 }
274
275 zs->avail_out = iov->iov_len;
276 zs->next_out = iov->iov_base;
277
278 /*
279 * Welcome to inflate semantics
280 *
281 * We need to loop while:
282 * - return is Z_OK
283 * - there are input available
284 * - we haven't completed a full page
285 */
286 do {
287 ret = inflate(zs, flush);
288 } while (ret == Z_OK && zs->avail_in
289 && (zs->total_out - start) < iov->iov_len);
290 if (ret == Z_OK && (zs->total_out - start) < iov->iov_len) {
291 error_setg(errp, "multifd %d: inflate generated too few output",
292 p->id);
293 return -1;
294 }
295 if (ret != Z_OK) {
296 error_setg(errp, "multifd %d: inflate returned %d instead of Z_OK",
297 p->id, ret);
298 return -1;
299 }
300 }
301 out_size = zs->total_out - out_size;
302 if (out_size != expected_size) {
303 error_setg(errp, "multifd %d: packet size received %d size expected %d",
304 p->id, out_size, expected_size);
305 return -1;
306 }
307 return 0;
308 }
309
310 static MultiFDMethods multifd_zlib_ops = {
311 .send_setup = zlib_send_setup,
312 .send_cleanup = zlib_send_cleanup,
313 .send_prepare = zlib_send_prepare,
314 .send_write = zlib_send_write,
315 .recv_setup = zlib_recv_setup,
316 .recv_cleanup = zlib_recv_cleanup,
317 .recv_pages = zlib_recv_pages
318 };
319
320 static void multifd_zlib_register(void)
321 {
322 multifd_register_ops(MULTIFD_COMPRESSION_ZLIB, &multifd_zlib_ops);
323 }
324
325 migration_init(multifd_zlib_register);