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/kernel.h>
45 #include <sys/linker_set.h>
46 #include <sys/malloc.h>
48 MALLOC_DEFINE(M_COMPRESS, "compressor", "kernel compression subroutines");
50 struct compressor_methods {
52 void *(* const init)(size_t, int);
53 void (* const reset)(void *);
54 int (* const write)(void *, void *, size_t, compressor_cb_t, void *);
55 void (* const fini)(void *);
59 const struct compressor_methods *methods;
65 SET_DECLARE(compressors, struct compressor_methods);
69 #include <sys/zutil.h>
72 uint8_t *gz_buffer; /* output buffer */
73 size_t gz_bufsz; /* output buffer size */
74 off_t gz_off; /* offset into the output stream */
75 uint32_t gz_crc; /* stream CRC32 */
76 z_stream gz_stream; /* zlib state */
79 static void *gz_init(size_t maxiosize, int level);
80 static void gz_reset(void *stream);
81 static int gz_write(void *stream, void *data, size_t len, compressor_cb_t,
83 static void gz_fini(void *stream);
86 gz_alloc(void *arg __unused, u_int n, u_int sz)
90 * Memory for zlib state is allocated using M_NODUMP since it may be
91 * used to compress a kernel dump, and we don't want zlib to attempt to
92 * compress its own state.
94 return (malloc(n * sz, M_COMPRESS, M_WAITOK | M_ZERO | M_NODUMP));
98 gz_free(void *arg __unused, void *ptr)
101 free(ptr, M_COMPRESS);
105 gz_init(size_t maxiosize, int level)
110 s = gz_alloc(NULL, 1, roundup2(sizeof(*s), PAGE_SIZE));
111 s->gz_buffer = gz_alloc(NULL, 1, maxiosize);
112 s->gz_bufsz = maxiosize;
114 s->gz_stream.zalloc = gz_alloc;
115 s->gz_stream.zfree = gz_free;
116 s->gz_stream.opaque = NULL;
117 s->gz_stream.next_in = Z_NULL;
118 s->gz_stream.avail_in = 0;
120 error = deflateInit2(&s->gz_stream, level, Z_DEFLATED, -MAX_WBITS,
121 DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY);
135 gz_reset(void *stream)
139 const size_t hdrlen = 10;
145 (void)deflateReset(&s->gz_stream);
146 s->gz_stream.avail_out = s->gz_bufsz;
147 s->gz_stream.next_out = s->gz_buffer;
149 /* Write the gzip header to the output buffer. */
151 memset(hdr, 0, hdrlen);
156 s->gz_stream.next_out += hdrlen;
157 s->gz_stream.avail_out -= hdrlen;
161 gz_write(void *stream, void *data, size_t len, compressor_cb_t cb,
167 int error, zerror, zflag;
170 zflag = data == NULL ? Z_FINISH : Z_NO_FLUSH;
173 s->gz_stream.avail_in = len;
174 s->gz_stream.next_in = data;
175 s->gz_crc = crc32_raw(data, len, s->gz_crc);
181 zerror = deflate(&s->gz_stream, zflag);
182 if (zerror != Z_OK && zerror != Z_STREAM_END) {
187 if (s->gz_stream.avail_out == 0 || zerror == Z_STREAM_END) {
189 * Our output buffer is full or there's nothing left
190 * to produce, so we're flushing the buffer.
192 len = s->gz_bufsz - s->gz_stream.avail_out;
193 if (zerror == Z_STREAM_END) {
195 * Try to pack as much of the trailer into the
196 * output buffer as we can.
198 ((uint32_t *)trailer)[0] = s->gz_crc;
199 ((uint32_t *)trailer)[1] =
200 s->gz_stream.total_in;
201 room = MIN(sizeof(trailer),
203 memcpy(s->gz_buffer + len, trailer, room);
207 error = cb(s->gz_buffer, len, s->gz_off, arg);
212 s->gz_stream.next_out = s->gz_buffer;
213 s->gz_stream.avail_out = s->gz_bufsz;
216 * If we couldn't pack the trailer into the output
217 * buffer, write it out now.
219 if (zerror == Z_STREAM_END && room < sizeof(trailer))
220 error = cb(trailer + room,
221 sizeof(trailer) - room, s->gz_off, arg);
223 } while (zerror != Z_STREAM_END &&
224 (zflag == Z_FINISH || s->gz_stream.avail_in > 0));
230 gz_fini(void *stream)
235 (void)deflateEnd(&s->gz_stream);
236 gz_free(NULL, s->gz_buffer);
240 struct compressor_methods gzip_methods = {
241 .format = COMPRESS_GZIP,
247 DATA_SET(compressors, gzip_methods);
253 #define ZSTD_STATIC_LINKING_ONLY
254 #include <contrib/zstd/lib/zstd.h>
256 struct zstdio_stream {
257 ZSTD_CCtx *zst_stream;
258 ZSTD_inBuffer zst_inbuffer;
259 ZSTD_outBuffer zst_outbuffer;
260 uint8_t * zst_buffer; /* output buffer */
261 size_t zst_maxiosz; /* Max output IO size */
262 off_t zst_off; /* offset into the output stream */
263 void * zst_static_wkspc;
266 static void *zstdio_init(size_t maxiosize, int level);
267 static void zstdio_reset(void *stream);
268 static int zstdio_write(void *stream, void *data, size_t len,
269 compressor_cb_t, void *);
270 static void zstdio_fini(void *stream);
273 zstdio_init(size_t maxiosize, int level)
275 ZSTD_CCtx *dump_compressor;
276 struct zstdio_stream *s;
277 void *wkspc, *owkspc, *buffer;
278 size_t wkspc_size, buf_size;
280 wkspc_size = ZSTD_estimateCStreamSize(level);
281 owkspc = wkspc = malloc(wkspc_size + 8, M_COMPRESS,
282 M_WAITOK | M_NODUMP);
283 /* Zstd API requires 8-byte alignment. */
284 if ((uintptr_t)wkspc % 8 != 0)
285 wkspc = (void *)roundup2((uintptr_t)wkspc, 8);
287 dump_compressor = ZSTD_initStaticCCtx(wkspc, wkspc_size);
288 if (dump_compressor == NULL) {
289 free(owkspc, M_COMPRESS);
290 printf("%s: workspace too small.\n", __func__);
294 (void)ZSTD_CCtx_setParameter(dump_compressor, ZSTD_p_checksumFlag, 1);
296 buf_size = ZSTD_CStreamOutSize() * 2;
297 buffer = malloc(buf_size, M_COMPRESS, M_WAITOK | M_NODUMP);
299 s = malloc(sizeof(*s), M_COMPRESS, M_NODUMP | M_WAITOK);
300 s->zst_buffer = buffer;
301 s->zst_outbuffer.dst = buffer;
302 s->zst_outbuffer.size = buf_size;
303 s->zst_maxiosz = maxiosize;
304 s->zst_stream = dump_compressor;
305 s->zst_static_wkspc = owkspc;
313 zstdio_reset(void *stream)
315 struct zstdio_stream *s;
319 res = ZSTD_resetCStream(s->zst_stream, 0);
320 if (ZSTD_isError(res))
321 panic("%s: could not reset stream %p: %s\n", __func__, s,
322 ZSTD_getErrorName(res));
325 s->zst_inbuffer.src = NULL;
326 s->zst_inbuffer.size = 0;
327 s->zst_inbuffer.pos = 0;
328 s->zst_outbuffer.pos = 0;
332 zst_flush_intermediate(struct zstdio_stream *s, compressor_cb_t cb, void *arg)
334 size_t bytes_to_dump;
337 /* Flush as many full output blocks as possible. */
338 /* XXX: 4096 is arbitrary safe HDD block size for kernel dumps */
339 while (s->zst_outbuffer.pos >= 4096) {
340 bytes_to_dump = rounddown(s->zst_outbuffer.pos, 4096);
342 if (bytes_to_dump > s->zst_maxiosz)
343 bytes_to_dump = s->zst_maxiosz;
345 error = cb(s->zst_buffer, bytes_to_dump, s->zst_off, arg);
350 * Shift any non-full blocks up to the front of the output
353 s->zst_outbuffer.pos -= bytes_to_dump;
354 memmove(s->zst_outbuffer.dst,
355 (char *)s->zst_outbuffer.dst + bytes_to_dump,
356 s->zst_outbuffer.pos);
357 s->zst_off += bytes_to_dump;
363 zstdio_flush(struct zstdio_stream *s, compressor_cb_t cb, void *arg)
369 * Positive return indicates unflushed data remaining; need to call
370 * endStream again after clearing out room in output buffer.
373 lastpos = s->zst_outbuffer.pos;
375 rc = ZSTD_endStream(s->zst_stream, &s->zst_outbuffer);
376 if (ZSTD_isError(rc)) {
377 printf("%s: ZSTD_endStream failed (%s)\n", __func__,
378 ZSTD_getErrorName(rc));
381 if (lastpos == s->zst_outbuffer.pos) {
382 printf("%s: did not make forward progress endStream %zu\n",
387 error = zst_flush_intermediate(s, cb, arg);
391 lastpos = s->zst_outbuffer.pos;
395 * We've already done an intermediate flush, so all full blocks have
396 * been written. Only a partial block remains. Padding happens in a
399 if (s->zst_outbuffer.pos != 0) {
400 error = cb(s->zst_buffer, s->zst_outbuffer.pos, s->zst_off,
410 zstdio_write(void *stream, void *data, size_t len, compressor_cb_t cb,
413 struct zstdio_stream *s;
419 return (zstdio_flush(s, cb, arg));
421 s->zst_inbuffer.src = data;
422 s->zst_inbuffer.size = len;
423 s->zst_inbuffer.pos = 0;
426 while (s->zst_inbuffer.pos < s->zst_inbuffer.size) {
427 rc = ZSTD_compressStream(s->zst_stream, &s->zst_outbuffer,
429 if (ZSTD_isError(rc)) {
430 printf("%s: Compress failed on %p! (%s)\n",
431 __func__, data, ZSTD_getErrorName(rc));
435 if (lastpos == s->zst_inbuffer.pos) {
437 * XXX: May need flushStream to make forward progress
439 printf("ZSTD: did not make forward progress @pos %zu\n",
443 lastpos = s->zst_inbuffer.pos;
445 error = zst_flush_intermediate(s, cb, arg);
453 zstdio_fini(void *stream)
455 struct zstdio_stream *s;
458 if (s->zst_static_wkspc != NULL)
459 free(s->zst_static_wkspc, M_COMPRESS);
461 ZSTD_freeCCtx(s->zst_stream);
462 free(s->zst_buffer, M_COMPRESS);
466 static struct compressor_methods zstd_methods = {
467 .format = COMPRESS_ZSTD,
469 .reset = zstdio_reset,
470 .write = zstdio_write,
473 DATA_SET(compressors, zstd_methods);
478 compressor_avail(int format)
480 struct compressor_methods **iter;
482 SET_FOREACH(iter, compressors) {
483 if ((*iter)->format == format)
490 compressor_init(compressor_cb_t cb, int format, size_t maxiosize, int level,
493 struct compressor_methods **iter;
494 struct compressor *s;
497 SET_FOREACH(iter, compressors) {
498 if ((*iter)->format == format)
504 priv = (*iter)->init(maxiosize, level);
508 s = malloc(sizeof(*s), M_COMPRESS, M_WAITOK | M_ZERO);
509 s->methods = (*iter);
517 compressor_reset(struct compressor *stream)
520 stream->methods->reset(stream->priv);
524 compressor_write(struct compressor *stream, void *data, size_t len)
527 return (stream->methods->write(stream->priv, data, len, stream->cb,
532 compressor_flush(struct compressor *stream)
535 return (stream->methods->write(stream->priv, NULL, 0, stream->cb,
540 compressor_fini(struct compressor *stream)
543 stream->methods->fini(stream->priv);