2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2014, 2017 Mark Johnston <markj@FreeBSD.org>
5 * Copyright (c) 2017 Conrad Meyer <cem@FreeBSD.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in
14 * the documentation and/or other materials provided with the
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * Subroutines used for writing compressed user process and kernel core dumps.
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
38 #include "opt_zstdio.h"
40 #include <sys/param.h>
41 #include <sys/systm.h>
43 #include <sys/compressor.h>
44 #include <sys/endian.h>
45 #include <sys/kernel.h>
46 #include <sys/linker_set.h>
47 #include <sys/malloc.h>
49 MALLOC_DEFINE(M_COMPRESS, "compressor", "kernel compression subroutines");
51 struct compressor_methods {
53 void *(* const init)(size_t, int);
54 void (* const reset)(void *);
55 int (* const write)(void *, void *, size_t, compressor_cb_t, void *);
56 void (* const fini)(void *);
60 const struct compressor_methods *methods;
66 SET_DECLARE(compressors, struct compressor_methods);
70 #include <contrib/zlib/zutil.h>
73 uint8_t *gz_buffer; /* output buffer */
74 size_t gz_bufsz; /* output buffer size */
75 off_t gz_off; /* offset into the output stream */
76 uint32_t gz_crc; /* stream CRC32 */
77 z_stream gz_stream; /* zlib state */
80 static void *gz_init(size_t maxiosize, int level);
81 static void gz_reset(void *stream);
82 static int gz_write(void *stream, void *data, size_t len, compressor_cb_t,
84 static void gz_fini(void *stream);
87 gz_alloc(void *arg __unused, u_int n, u_int sz)
91 * Memory for zlib state is allocated using M_NODUMP since it may be
92 * used to compress a kernel dump, and we don't want zlib to attempt to
93 * compress its own state.
95 return (malloc(n * sz, M_COMPRESS, M_WAITOK | M_ZERO | M_NODUMP));
99 gz_free(void *arg __unused, void *ptr)
102 free(ptr, M_COMPRESS);
106 gz_init(size_t maxiosize, int level)
111 s = gz_alloc(NULL, 1, roundup2(sizeof(*s), PAGE_SIZE));
112 s->gz_buffer = gz_alloc(NULL, 1, maxiosize);
113 s->gz_bufsz = maxiosize;
115 s->gz_stream.zalloc = gz_alloc;
116 s->gz_stream.zfree = gz_free;
117 s->gz_stream.opaque = NULL;
118 s->gz_stream.next_in = Z_NULL;
119 s->gz_stream.avail_in = 0;
121 if (level != Z_DEFAULT_COMPRESSION) {
122 if (level < Z_BEST_SPEED)
123 level = Z_BEST_SPEED;
124 else if (level > Z_BEST_COMPRESSION)
125 level = Z_BEST_COMPRESSION;
128 error = deflateInit2(&s->gz_stream, level, Z_DEFLATED, -MAX_WBITS,
129 DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY);
143 gz_reset(void *stream)
147 const size_t hdrlen = 10;
151 s->gz_crc = crc32(0L, Z_NULL, 0);
153 (void)deflateReset(&s->gz_stream);
154 s->gz_stream.avail_out = s->gz_bufsz;
155 s->gz_stream.next_out = s->gz_buffer;
157 /* Write the gzip header to the output buffer. */
159 memset(hdr, 0, hdrlen);
164 s->gz_stream.next_out += hdrlen;
165 s->gz_stream.avail_out -= hdrlen;
169 gz_write(void *stream, void *data, size_t len, compressor_cb_t cb,
175 int error, zerror, zflag;
178 zflag = data == NULL ? Z_FINISH : Z_NO_FLUSH;
181 s->gz_stream.avail_in = len;
182 s->gz_stream.next_in = data;
183 s->gz_crc = crc32(s->gz_crc, data, len);
188 zerror = deflate(&s->gz_stream, zflag);
189 if (zerror != Z_OK && zerror != Z_STREAM_END) {
194 if (s->gz_stream.avail_out == 0 || zerror == Z_STREAM_END) {
196 * Our output buffer is full or there's nothing left
197 * to produce, so we're flushing the buffer.
199 len = s->gz_bufsz - s->gz_stream.avail_out;
200 if (zerror == Z_STREAM_END) {
202 * Try to pack as much of the trailer into the
203 * output buffer as we can.
205 ((uint32_t *)trailer)[0] = htole32(s->gz_crc);
206 ((uint32_t *)trailer)[1] =
207 htole32(s->gz_stream.total_in);
208 room = MIN(sizeof(trailer),
210 memcpy(s->gz_buffer + len, trailer, room);
214 error = cb(s->gz_buffer, len, s->gz_off, arg);
219 s->gz_stream.next_out = s->gz_buffer;
220 s->gz_stream.avail_out = s->gz_bufsz;
223 * If we couldn't pack the trailer into the output
224 * buffer, write it out now.
226 if (zerror == Z_STREAM_END && room < sizeof(trailer))
227 error = cb(trailer + room,
228 sizeof(trailer) - room, s->gz_off, arg);
230 } while (zerror != Z_STREAM_END &&
231 (zflag == Z_FINISH || s->gz_stream.avail_in > 0));
237 gz_fini(void *stream)
242 (void)deflateEnd(&s->gz_stream);
243 gz_free(NULL, s->gz_buffer);
247 struct compressor_methods gzip_methods = {
248 .format = COMPRESS_GZIP,
254 DATA_SET(compressors, gzip_methods);
260 #define ZSTD_STATIC_LINKING_ONLY
261 #include <contrib/zstd/lib/zstd.h>
263 struct zstdio_stream {
264 ZSTD_CCtx *zst_stream;
265 ZSTD_inBuffer zst_inbuffer;
266 ZSTD_outBuffer zst_outbuffer;
267 uint8_t * zst_buffer; /* output buffer */
268 size_t zst_maxiosz; /* Max output IO size */
269 off_t zst_off; /* offset into the output stream */
270 void * zst_static_wkspc;
273 static void *zstdio_init(size_t maxiosize, int level);
274 static void zstdio_reset(void *stream);
275 static int zstdio_write(void *stream, void *data, size_t len,
276 compressor_cb_t, void *);
277 static void zstdio_fini(void *stream);
280 zstdio_init(size_t maxiosize, int level)
282 ZSTD_CCtx *dump_compressor;
283 struct zstdio_stream *s;
284 void *wkspc, *owkspc, *buffer;
285 size_t wkspc_size, buf_size, rc;
288 wkspc_size = ZSTD_estimateCStreamSize(level);
289 owkspc = wkspc = malloc(wkspc_size + 8, M_COMPRESS,
290 M_WAITOK | M_NODUMP);
291 /* Zstd API requires 8-byte alignment. */
292 if ((uintptr_t)wkspc % 8 != 0)
293 wkspc = (void *)roundup2((uintptr_t)wkspc, 8);
295 dump_compressor = ZSTD_initStaticCCtx(wkspc, wkspc_size);
296 if (dump_compressor == NULL) {
297 printf("%s: workspace too small.\n", __func__);
301 rc = ZSTD_CCtx_setParameter(dump_compressor, ZSTD_c_checksumFlag, 1);
302 if (ZSTD_isError(rc)) {
303 printf("%s: error setting checksumFlag: %s\n", __func__,
304 ZSTD_getErrorName(rc));
307 rc = ZSTD_CCtx_setParameter(dump_compressor, ZSTD_c_compressionLevel,
309 if (ZSTD_isError(rc)) {
310 printf("%s: error setting compressLevel: %s\n", __func__,
311 ZSTD_getErrorName(rc));
315 buf_size = ZSTD_CStreamOutSize() * 2;
316 buffer = malloc(buf_size, M_COMPRESS, M_WAITOK | M_NODUMP);
318 s = malloc(sizeof(*s), M_COMPRESS, M_NODUMP | M_WAITOK);
319 s->zst_buffer = buffer;
320 s->zst_outbuffer.dst = buffer;
321 s->zst_outbuffer.size = buf_size;
322 s->zst_maxiosz = maxiosize;
323 s->zst_stream = dump_compressor;
324 s->zst_static_wkspc = owkspc;
330 free(owkspc, M_COMPRESS);
335 zstdio_reset(void *stream)
337 struct zstdio_stream *s;
341 res = ZSTD_resetCStream(s->zst_stream, 0);
342 if (ZSTD_isError(res))
343 panic("%s: could not reset stream %p: %s\n", __func__, s,
344 ZSTD_getErrorName(res));
347 s->zst_inbuffer.src = NULL;
348 s->zst_inbuffer.size = 0;
349 s->zst_inbuffer.pos = 0;
350 s->zst_outbuffer.pos = 0;
354 zst_flush_intermediate(struct zstdio_stream *s, compressor_cb_t cb, void *arg)
356 size_t bytes_to_dump;
359 /* Flush as many full output blocks as possible. */
360 /* XXX: 4096 is arbitrary safe HDD block size for kernel dumps */
361 while (s->zst_outbuffer.pos >= 4096) {
362 bytes_to_dump = rounddown(s->zst_outbuffer.pos, 4096);
364 if (bytes_to_dump > s->zst_maxiosz)
365 bytes_to_dump = s->zst_maxiosz;
367 error = cb(s->zst_buffer, bytes_to_dump, s->zst_off, arg);
372 * Shift any non-full blocks up to the front of the output
375 s->zst_outbuffer.pos -= bytes_to_dump;
376 memmove(s->zst_outbuffer.dst,
377 (char *)s->zst_outbuffer.dst + bytes_to_dump,
378 s->zst_outbuffer.pos);
379 s->zst_off += bytes_to_dump;
385 zstdio_flush(struct zstdio_stream *s, compressor_cb_t cb, void *arg)
391 * Positive return indicates unflushed data remaining; need to call
392 * endStream again after clearing out room in output buffer.
395 lastpos = s->zst_outbuffer.pos;
397 rc = ZSTD_endStream(s->zst_stream, &s->zst_outbuffer);
398 if (ZSTD_isError(rc)) {
399 printf("%s: ZSTD_endStream failed (%s)\n", __func__,
400 ZSTD_getErrorName(rc));
403 if (lastpos == s->zst_outbuffer.pos) {
404 printf("%s: did not make forward progress endStream %zu\n",
409 error = zst_flush_intermediate(s, cb, arg);
413 lastpos = s->zst_outbuffer.pos;
417 * We've already done an intermediate flush, so all full blocks have
418 * been written. Only a partial block remains. Padding happens in a
421 if (s->zst_outbuffer.pos != 0) {
422 error = cb(s->zst_buffer, s->zst_outbuffer.pos, s->zst_off,
432 zstdio_write(void *stream, void *data, size_t len, compressor_cb_t cb,
435 struct zstdio_stream *s;
441 return (zstdio_flush(s, cb, arg));
443 s->zst_inbuffer.src = data;
444 s->zst_inbuffer.size = len;
445 s->zst_inbuffer.pos = 0;
448 while (s->zst_inbuffer.pos < s->zst_inbuffer.size) {
449 rc = ZSTD_compressStream(s->zst_stream, &s->zst_outbuffer,
451 if (ZSTD_isError(rc)) {
452 printf("%s: Compress failed on %p! (%s)\n",
453 __func__, data, ZSTD_getErrorName(rc));
457 if (lastpos == s->zst_inbuffer.pos) {
459 * XXX: May need flushStream to make forward progress
461 printf("ZSTD: did not make forward progress @pos %zu\n",
465 lastpos = s->zst_inbuffer.pos;
467 error = zst_flush_intermediate(s, cb, arg);
475 zstdio_fini(void *stream)
477 struct zstdio_stream *s;
480 if (s->zst_static_wkspc != NULL)
481 free(s->zst_static_wkspc, M_COMPRESS);
483 ZSTD_freeCCtx(s->zst_stream);
484 free(s->zst_buffer, M_COMPRESS);
488 static struct compressor_methods zstd_methods = {
489 .format = COMPRESS_ZSTD,
491 .reset = zstdio_reset,
492 .write = zstdio_write,
495 DATA_SET(compressors, zstd_methods);
500 compressor_avail(int format)
502 struct compressor_methods **iter;
504 SET_FOREACH(iter, compressors) {
505 if ((*iter)->format == format)
512 compressor_init(compressor_cb_t cb, int format, size_t maxiosize, int level,
515 struct compressor_methods **iter;
516 struct compressor *s;
519 SET_FOREACH(iter, compressors) {
520 if ((*iter)->format == format)
523 if (iter == SET_LIMIT(compressors))
526 priv = (*iter)->init(maxiosize, level);
530 s = malloc(sizeof(*s), M_COMPRESS, M_WAITOK | M_ZERO);
531 s->methods = (*iter);
539 compressor_reset(struct compressor *stream)
542 stream->methods->reset(stream->priv);
546 compressor_write(struct compressor *stream, void *data, size_t len)
549 return (stream->methods->write(stream->priv, data, len, stream->cb,
554 compressor_flush(struct compressor *stream)
557 return (stream->methods->write(stream->priv, NULL, 0, stream->cb,
562 compressor_fini(struct compressor *stream)
565 stream->methods->fini(stream->priv);