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/gsb_crc32.h>
70 #include <sys/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 error = deflateInit2(&s->gz_stream, level, Z_DEFLATED, -MAX_WBITS,
122 DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY);
136 gz_reset(void *stream)
140 const size_t hdrlen = 10;
146 (void)deflateReset(&s->gz_stream);
147 s->gz_stream.avail_out = s->gz_bufsz;
148 s->gz_stream.next_out = s->gz_buffer;
150 /* Write the gzip header to the output buffer. */
152 memset(hdr, 0, hdrlen);
157 s->gz_stream.next_out += hdrlen;
158 s->gz_stream.avail_out -= hdrlen;
162 gz_write(void *stream, void *data, size_t len, compressor_cb_t cb,
168 int error, zerror, zflag;
171 zflag = data == NULL ? Z_FINISH : Z_NO_FLUSH;
174 s->gz_stream.avail_in = len;
175 s->gz_stream.next_in = data;
176 s->gz_crc = crc32_raw(data, len, s->gz_crc);
182 zerror = deflate(&s->gz_stream, zflag);
183 if (zerror != Z_OK && zerror != Z_STREAM_END) {
188 if (s->gz_stream.avail_out == 0 || zerror == Z_STREAM_END) {
190 * Our output buffer is full or there's nothing left
191 * to produce, so we're flushing the buffer.
193 len = s->gz_bufsz - s->gz_stream.avail_out;
194 if (zerror == Z_STREAM_END) {
196 * Try to pack as much of the trailer into the
197 * output buffer as we can.
199 ((uint32_t *)trailer)[0] = s->gz_crc;
200 ((uint32_t *)trailer)[1] =
201 s->gz_stream.total_in;
202 room = MIN(sizeof(trailer),
204 memcpy(s->gz_buffer + len, trailer, room);
208 error = cb(s->gz_buffer, len, s->gz_off, arg);
213 s->gz_stream.next_out = s->gz_buffer;
214 s->gz_stream.avail_out = s->gz_bufsz;
217 * If we couldn't pack the trailer into the output
218 * buffer, write it out now.
220 if (zerror == Z_STREAM_END && room < sizeof(trailer))
221 error = cb(trailer + room,
222 sizeof(trailer) - room, s->gz_off, arg);
224 } while (zerror != Z_STREAM_END &&
225 (zflag == Z_FINISH || s->gz_stream.avail_in > 0));
231 gz_fini(void *stream)
236 (void)deflateEnd(&s->gz_stream);
237 gz_free(NULL, s->gz_buffer);
241 struct compressor_methods gzip_methods = {
242 .format = COMPRESS_GZIP,
248 DATA_SET(compressors, gzip_methods);
254 #define ZSTD_STATIC_LINKING_ONLY
255 #include <contrib/zstd/lib/zstd.h>
257 struct zstdio_stream {
258 ZSTD_CCtx *zst_stream;
259 ZSTD_inBuffer zst_inbuffer;
260 ZSTD_outBuffer zst_outbuffer;
261 uint8_t * zst_buffer; /* output buffer */
262 size_t zst_maxiosz; /* Max output IO size */
263 off_t zst_off; /* offset into the output stream */
264 void * zst_static_wkspc;
267 static void *zstdio_init(size_t maxiosize, int level);
268 static void zstdio_reset(void *stream);
269 static int zstdio_write(void *stream, void *data, size_t len,
270 compressor_cb_t, void *);
271 static void zstdio_fini(void *stream);
274 zstdio_init(size_t maxiosize, int level)
276 ZSTD_CCtx *dump_compressor;
277 struct zstdio_stream *s;
278 void *wkspc, *owkspc, *buffer;
279 size_t wkspc_size, buf_size, rc;
282 wkspc_size = ZSTD_estimateCStreamSize(level);
283 owkspc = wkspc = malloc(wkspc_size + 8, M_COMPRESS,
284 M_WAITOK | M_NODUMP);
285 /* Zstd API requires 8-byte alignment. */
286 if ((uintptr_t)wkspc % 8 != 0)
287 wkspc = (void *)roundup2((uintptr_t)wkspc, 8);
289 dump_compressor = ZSTD_initStaticCCtx(wkspc, wkspc_size);
290 if (dump_compressor == NULL) {
291 printf("%s: workspace too small.\n", __func__);
295 rc = ZSTD_CCtx_setParameter(dump_compressor, ZSTD_c_checksumFlag, 1);
296 if (ZSTD_isError(rc)) {
297 printf("%s: error setting checksumFlag: %s\n", __func__,
298 ZSTD_getErrorName(rc));
301 rc = ZSTD_CCtx_setParameter(dump_compressor, ZSTD_c_compressionLevel,
303 if (ZSTD_isError(rc)) {
304 printf("%s: error setting compressLevel: %s\n", __func__,
305 ZSTD_getErrorName(rc));
309 buf_size = ZSTD_CStreamOutSize() * 2;
310 buffer = malloc(buf_size, M_COMPRESS, M_WAITOK | M_NODUMP);
312 s = malloc(sizeof(*s), M_COMPRESS, M_NODUMP | M_WAITOK);
313 s->zst_buffer = buffer;
314 s->zst_outbuffer.dst = buffer;
315 s->zst_outbuffer.size = buf_size;
316 s->zst_maxiosz = maxiosize;
317 s->zst_stream = dump_compressor;
318 s->zst_static_wkspc = owkspc;
324 free(owkspc, M_COMPRESS);
329 zstdio_reset(void *stream)
331 struct zstdio_stream *s;
335 res = ZSTD_resetCStream(s->zst_stream, 0);
336 if (ZSTD_isError(res))
337 panic("%s: could not reset stream %p: %s\n", __func__, s,
338 ZSTD_getErrorName(res));
341 s->zst_inbuffer.src = NULL;
342 s->zst_inbuffer.size = 0;
343 s->zst_inbuffer.pos = 0;
344 s->zst_outbuffer.pos = 0;
348 zst_flush_intermediate(struct zstdio_stream *s, compressor_cb_t cb, void *arg)
350 size_t bytes_to_dump;
353 /* Flush as many full output blocks as possible. */
354 /* XXX: 4096 is arbitrary safe HDD block size for kernel dumps */
355 while (s->zst_outbuffer.pos >= 4096) {
356 bytes_to_dump = rounddown(s->zst_outbuffer.pos, 4096);
358 if (bytes_to_dump > s->zst_maxiosz)
359 bytes_to_dump = s->zst_maxiosz;
361 error = cb(s->zst_buffer, bytes_to_dump, s->zst_off, arg);
366 * Shift any non-full blocks up to the front of the output
369 s->zst_outbuffer.pos -= bytes_to_dump;
370 memmove(s->zst_outbuffer.dst,
371 (char *)s->zst_outbuffer.dst + bytes_to_dump,
372 s->zst_outbuffer.pos);
373 s->zst_off += bytes_to_dump;
379 zstdio_flush(struct zstdio_stream *s, compressor_cb_t cb, void *arg)
385 * Positive return indicates unflushed data remaining; need to call
386 * endStream again after clearing out room in output buffer.
389 lastpos = s->zst_outbuffer.pos;
391 rc = ZSTD_endStream(s->zst_stream, &s->zst_outbuffer);
392 if (ZSTD_isError(rc)) {
393 printf("%s: ZSTD_endStream failed (%s)\n", __func__,
394 ZSTD_getErrorName(rc));
397 if (lastpos == s->zst_outbuffer.pos) {
398 printf("%s: did not make forward progress endStream %zu\n",
403 error = zst_flush_intermediate(s, cb, arg);
407 lastpos = s->zst_outbuffer.pos;
411 * We've already done an intermediate flush, so all full blocks have
412 * been written. Only a partial block remains. Padding happens in a
415 if (s->zst_outbuffer.pos != 0) {
416 error = cb(s->zst_buffer, s->zst_outbuffer.pos, s->zst_off,
426 zstdio_write(void *stream, void *data, size_t len, compressor_cb_t cb,
429 struct zstdio_stream *s;
435 return (zstdio_flush(s, cb, arg));
437 s->zst_inbuffer.src = data;
438 s->zst_inbuffer.size = len;
439 s->zst_inbuffer.pos = 0;
442 while (s->zst_inbuffer.pos < s->zst_inbuffer.size) {
443 rc = ZSTD_compressStream(s->zst_stream, &s->zst_outbuffer,
445 if (ZSTD_isError(rc)) {
446 printf("%s: Compress failed on %p! (%s)\n",
447 __func__, data, ZSTD_getErrorName(rc));
451 if (lastpos == s->zst_inbuffer.pos) {
453 * XXX: May need flushStream to make forward progress
455 printf("ZSTD: did not make forward progress @pos %zu\n",
459 lastpos = s->zst_inbuffer.pos;
461 error = zst_flush_intermediate(s, cb, arg);
469 zstdio_fini(void *stream)
471 struct zstdio_stream *s;
474 if (s->zst_static_wkspc != NULL)
475 free(s->zst_static_wkspc, M_COMPRESS);
477 ZSTD_freeCCtx(s->zst_stream);
478 free(s->zst_buffer, M_COMPRESS);
482 static struct compressor_methods zstd_methods = {
483 .format = COMPRESS_ZSTD,
485 .reset = zstdio_reset,
486 .write = zstdio_write,
489 DATA_SET(compressors, zstd_methods);
494 compressor_avail(int format)
496 struct compressor_methods **iter;
498 SET_FOREACH(iter, compressors) {
499 if ((*iter)->format == format)
506 compressor_init(compressor_cb_t cb, int format, size_t maxiosize, int level,
509 struct compressor_methods **iter;
510 struct compressor *s;
513 SET_FOREACH(iter, compressors) {
514 if ((*iter)->format == format)
517 if (iter == SET_LIMIT(compressors))
520 priv = (*iter)->init(maxiosize, level);
524 s = malloc(sizeof(*s), M_COMPRESS, M_WAITOK | M_ZERO);
525 s->methods = (*iter);
533 compressor_reset(struct compressor *stream)
536 stream->methods->reset(stream->priv);
540 compressor_write(struct compressor *stream, void *data, size_t len)
543 return (stream->methods->write(stream->priv, data, len, stream->cb,
548 compressor_flush(struct compressor *stream)
551 return (stream->methods->write(stream->priv, NULL, 0, stream->cb,
556 compressor_fini(struct compressor *stream)
559 stream->methods->fini(stream->priv);