1// SPDX-License-Identifier: GPL-2.0-or-later
2
3/* P9 gunzip sample code for demonstrating the P9 NX hardware
4 * interface.  Not intended for productive uses or for performance or
5 * compression ratio measurements.  Note also that /dev/crypto/gzip,
6 * VAS and skiboot support are required
7 *
8 * Copyright 2020 IBM Corp.
9 *
10 * Author: Bulent Abali <abali@us.ibm.com>
11 *
12 * https://github.com/libnxz/power-gzip for zlib api and other utils
13 * Definitions of acronyms used here.  See
14 * P9 NX Gzip Accelerator User's Manual for details:
15 * https://github.com/libnxz/power-gzip/blob/develop/doc/power_nx_gzip_um.pdf
16 *
17 * adler/crc: 32 bit checksums appended to stream tail
18 * ce:       completion extension
19 * cpb:      coprocessor parameter block (metadata)
20 * crb:      coprocessor request block (command)
21 * csb:      coprocessor status block (status)
22 * dht:      dynamic huffman table
23 * dde:      data descriptor element (address, length)
24 * ddl:      list of ddes
25 * dh/fh:    dynamic and fixed huffman types
26 * fc:       coprocessor function code
27 * histlen:  history/dictionary length
28 * history:  sliding window of up to 32KB of data
29 * lzcount:  Deflate LZ symbol counts
30 * rembytecnt: remaining byte count
31 * sfbt:     source final block type; last block's type during decomp
32 * spbc:     source processed byte count
33 * subc:     source unprocessed bit count
34 * tebc:     target ending bit count; valid bits in the last byte
35 * tpbc:     target processed byte count
36 * vas:      virtual accelerator switch; the user mode interface
37 */
38
39#define _ISOC11_SOURCE	// For aligned_alloc()
40#define _DEFAULT_SOURCE	// For endian.h
41
42#include <stdio.h>
43#include <stdlib.h>
44#include <string.h>
45#include <unistd.h>
46#include <stdint.h>
47#include <sys/types.h>
48#include <sys/stat.h>
49#include <sys/time.h>
50#include <sys/fcntl.h>
51#include <sys/mman.h>
52#include <endian.h>
53#include <bits/endian.h>
54#include <sys/ioctl.h>
55#include <assert.h>
56#include <errno.h>
57#include <signal.h>
58#include "nxu.h"
59#include "nx.h"
60#include "crb.h"
61
62int nx_dbg;
63FILE *nx_gzip_log;
64
65#define NX_MIN(X, Y) (((X) < (Y))?(X):(Y))
66#define NX_MAX(X, Y) (((X) > (Y))?(X):(Y))
67
68#define GETINPC(X) fgetc(X)
69#define FNAME_MAX 1024
70
71/* fifo queue management */
72#define fifo_used_bytes(used) (used)
73#define fifo_free_bytes(used, len) ((len)-(used))
74/* amount of free bytes in the first and last parts */
75#define fifo_free_first_bytes(cur, used, len)  ((((cur)+(used)) <= (len)) \
76						  ? (len)-((cur)+(used)) : 0)
77#define fifo_free_last_bytes(cur, used, len)   ((((cur)+(used)) <= (len)) \
78						  ? (cur) : (len)-(used))
79/* amount of used bytes in the first and last parts */
80#define fifo_used_first_bytes(cur, used, len)  ((((cur)+(used)) <= (len)) \
81						  ? (used) : (len)-(cur))
82#define fifo_used_last_bytes(cur, used, len)   ((((cur)+(used)) <= (len)) \
83						  ? 0 : ((used)+(cur))-(len))
84/* first and last free parts start here */
85#define fifo_free_first_offset(cur, used)      ((cur)+(used))
86#define fifo_free_last_offset(cur, used, len)  \
87					   fifo_used_last_bytes(cur, used, len)
88/* first and last used parts start here */
89#define fifo_used_first_offset(cur)            (cur)
90#define fifo_used_last_offset(cur)             (0)
91
92const int fifo_in_len = 1<<24;
93const int fifo_out_len = 1<<24;
94const int page_sz = 1<<16;
95const int line_sz = 1<<7;
96const int window_max = 1<<15;
97
98/*
99 * Adds an (address, len) pair to the list of ddes (ddl) and updates
100 * the base dde.  ddl[0] is the only dde in a direct dde which
101 * contains a single (addr,len) pair.  For more pairs, ddl[0] becomes
102 * the indirect (base) dde that points to a list of direct ddes.
103 * See Section 6.4 of the NX-gzip user manual for DDE description.
104 * Addr=NULL, len=0 clears the ddl[0].  Returns the total number of
105 * bytes in ddl.  Caller is responsible for allocting the array of
106 * nx_dde_t *ddl.  If N addresses are required in the scatter-gather
107 * list, the ddl array must have N+1 entries minimum.
108 */
109static inline uint32_t nx_append_dde(struct nx_dde_t *ddl, void *addr,
110					uint32_t len)
111{
112	uint32_t ddecnt;
113	uint32_t bytes;
114
115	if (addr == NULL && len == 0) {
116		clearp_dde(ddl);
117		return 0;
118	}
119
120	NXPRT(fprintf(stderr, "%d: %s addr %p len %x\n", __LINE__, addr,
121			__func__, len));
122
123	/* Number of ddes in the dde list ; == 0 when it is a direct dde */
124	ddecnt = getpnn(ddl, dde_count);
125	bytes = getp32(ddl, ddebc);
126
127	if (ddecnt == 0 && bytes == 0) {
128		/* First dde is unused; make it a direct dde */
129		bytes = len;
130		putp32(ddl, ddebc, bytes);
131		putp64(ddl, ddead, (uint64_t) addr);
132	} else if (ddecnt == 0) {
133		/* Converting direct to indirect dde
134		 * ddl[0] becomes head dde of ddl
135		 * copy direct to indirect first.
136		 */
137		ddl[1] = ddl[0];
138
139		/* Add the new dde next */
140		clear_dde(ddl[2]);
141		put32(ddl[2], ddebc, len);
142		put64(ddl[2], ddead, (uint64_t) addr);
143
144		/* Ddl head points to 2 direct ddes */
145		ddecnt = 2;
146		putpnn(ddl, dde_count, ddecnt);
147		bytes = bytes + len;
148		putp32(ddl, ddebc, bytes);
149		/* Pointer to the first direct dde */
150		putp64(ddl, ddead, (uint64_t) &ddl[1]);
151	} else {
152		/* Append a dde to an existing indirect ddl */
153		++ddecnt;
154		clear_dde(ddl[ddecnt]);
155		put64(ddl[ddecnt], ddead, (uint64_t) addr);
156		put32(ddl[ddecnt], ddebc, len);
157
158		putpnn(ddl, dde_count, ddecnt);
159		bytes = bytes + len;
160		putp32(ddl, ddebc, bytes); /* byte sum of all dde */
161	}
162	return bytes;
163}
164
165/*
166 * Touch specified number of pages represented in number bytes
167 * beginning from the first buffer in a dde list.
168 * Do not touch the pages past buf_sz-th byte's page.
169 *
170 * Set buf_sz = 0 to touch all pages described by the ddep.
171 */
172static int nx_touch_pages_dde(struct nx_dde_t *ddep, long buf_sz, long page_sz,
173				int wr)
174{
175	uint32_t indirect_count;
176	uint32_t buf_len;
177	long total;
178	uint64_t buf_addr;
179	struct nx_dde_t *dde_list;
180	int i;
181
182	assert(!!ddep);
183
184	indirect_count = getpnn(ddep, dde_count);
185
186	NXPRT(fprintf(stderr, "%s dde_count %d request len ", __func__,
187			indirect_count));
188	NXPRT(fprintf(stderr, "0x%lx\n", buf_sz));
189
190	if (indirect_count == 0) {
191		/* Direct dde */
192		buf_len = getp32(ddep, ddebc);
193		buf_addr = getp64(ddep, ddead);
194
195		NXPRT(fprintf(stderr, "touch direct ddebc 0x%x ddead %p\n",
196				buf_len, (void *)buf_addr));
197
198		if (buf_sz == 0)
199			nxu_touch_pages((void *)buf_addr, buf_len, page_sz, wr);
200		else
201			nxu_touch_pages((void *)buf_addr, NX_MIN(buf_len,
202					buf_sz), page_sz, wr);
203
204		return ERR_NX_OK;
205	}
206
207	/* Indirect dde */
208	if (indirect_count > MAX_DDE_COUNT)
209		return ERR_NX_EXCESSIVE_DDE;
210
211	/* First address of the list */
212	dde_list = (struct nx_dde_t *) getp64(ddep, ddead);
213
214	if (buf_sz == 0)
215		buf_sz = getp32(ddep, ddebc);
216
217	total = 0;
218	for (i = 0; i < indirect_count; i++) {
219		buf_len = get32(dde_list[i], ddebc);
220		buf_addr = get64(dde_list[i], ddead);
221		total += buf_len;
222
223		NXPRT(fprintf(stderr, "touch loop len 0x%x ddead %p total ",
224				buf_len, (void *)buf_addr));
225		NXPRT(fprintf(stderr, "0x%lx\n", total));
226
227		/* Touching fewer pages than encoded in the ddebc */
228		if (total > buf_sz) {
229			buf_len = NX_MIN(buf_len, total - buf_sz);
230			nxu_touch_pages((void *)buf_addr, buf_len, page_sz, wr);
231			NXPRT(fprintf(stderr, "touch loop break len 0x%x ",
232				      buf_len));
233			NXPRT(fprintf(stderr, "ddead %p\n", (void *)buf_addr));
234			break;
235		}
236		nxu_touch_pages((void *)buf_addr, buf_len, page_sz, wr);
237	}
238	return ERR_NX_OK;
239}
240
241/*
242 * Src and dst buffers are supplied in scatter gather lists.
243 * NX function code and other parameters supplied in cmdp.
244 */
245static int nx_submit_job(struct nx_dde_t *src, struct nx_dde_t *dst,
246			 struct nx_gzip_crb_cpb_t *cmdp, void *handle)
247{
248	uint64_t csbaddr;
249
250	memset((void *)&cmdp->crb.csb, 0, sizeof(cmdp->crb.csb));
251
252	cmdp->crb.source_dde = *src;
253	cmdp->crb.target_dde = *dst;
254
255	/* Status, output byte count in tpbc */
256	csbaddr = ((uint64_t) &cmdp->crb.csb) & csb_address_mask;
257	put64(cmdp->crb, csb_address, csbaddr);
258
259	/* NX reports input bytes in spbc; cleared */
260	cmdp->cpb.out_spbc_comp_wrap = 0;
261	cmdp->cpb.out_spbc_comp_with_count = 0;
262	cmdp->cpb.out_spbc_decomp = 0;
263
264	/* Clear output */
265	put32(cmdp->cpb, out_crc, INIT_CRC);
266	put32(cmdp->cpb, out_adler, INIT_ADLER);
267
268	/* Submit the crb, the job descriptor, to the accelerator. */
269	return nxu_submit_job(cmdp, handle);
270}
271
272int decompress_file(int argc, char **argv, void *devhandle)
273{
274	FILE *inpf = NULL;
275	FILE *outf = NULL;
276
277	int c, expect, i, cc, rc = 0;
278	char gzfname[FNAME_MAX];
279
280	/* Queuing, file ops, byte counting */
281	char *fifo_in, *fifo_out;
282	int used_in, cur_in, used_out, cur_out, read_sz, n;
283	int first_free, last_free, first_used, last_used;
284	int first_offset, last_offset;
285	int write_sz, free_space, source_sz;
286	int source_sz_estimate, target_sz_estimate;
287	uint64_t last_comp_ratio = 0; /* 1000 max */
288	uint64_t total_out = 0;
289	int is_final, is_eof;
290
291	/* nx hardware */
292	int sfbt, subc, spbc, tpbc, nx_ce, fc, resuming = 0;
293	int history_len = 0;
294	struct nx_gzip_crb_cpb_t cmd, *cmdp;
295	struct nx_dde_t *ddl_in;
296	struct nx_dde_t dde_in[6] __aligned(128);
297	struct nx_dde_t *ddl_out;
298	struct nx_dde_t dde_out[6] __aligned(128);
299	int pgfault_retries;
300
301	/* when using mmap'ed files */
302	off_t input_file_offset;
303
304	if (argc > 2) {
305		fprintf(stderr, "usage: %s <fname> or stdin\n", argv[0]);
306		fprintf(stderr, "    writes to stdout or <fname>.nx.gunzip\n");
307		return -1;
308	}
309
310	if (argc == 1) {
311		inpf = stdin;
312		outf = stdout;
313	} else if (argc == 2) {
314		char w[1024];
315		char *wp;
316
317		inpf = fopen(argv[1], "r");
318		if (inpf == NULL) {
319			perror(argv[1]);
320			return -1;
321		}
322
323		/* Make a new file name to write to.  Ignoring '.gz' */
324		wp = (NULL != (wp = strrchr(argv[1], '/'))) ? (wp+1) : argv[1];
325		strcpy(w, wp);
326		strcat(w, ".nx.gunzip");
327
328		outf = fopen(w, "w");
329		if (outf == NULL) {
330			perror(w);
331			return -1;
332		}
333	}
334
335	/* Decode the gzip header */
336	c = GETINPC(inpf); expect = 0x1f; /* ID1 */
337	if (c != expect)
338		goto err1;
339
340	c = GETINPC(inpf); expect = 0x8b; /* ID2 */
341	if (c != expect)
342		goto err1;
343
344	c = GETINPC(inpf); expect = 0x08; /* CM */
345	if (c != expect)
346		goto err1;
347
348	int flg = GETINPC(inpf); /* FLG */
349
350	if (flg & 0xE0 || flg & 0x4 || flg == EOF)
351		goto err2;
352
353	fprintf(stderr, "gzHeader FLG %x\n", flg);
354
355	/* Read 6 bytes; ignoring the MTIME, XFL, OS fields in this
356	 * sample code.
357	 */
358	for (i = 0; i < 6; i++) {
359		char tmp[10];
360
361		tmp[i] = GETINPC(inpf);
362		if (tmp[i] == EOF)
363			goto err3;
364		fprintf(stderr, "%02x ", tmp[i]);
365		if (i == 5)
366			fprintf(stderr, "\n");
367	}
368	fprintf(stderr, "gzHeader MTIME, XFL, OS ignored\n");
369
370	/* FNAME */
371	if (flg & 0x8) {
372		int k = 0;
373
374		do {
375			c = GETINPC(inpf);
376			if (c == EOF || k >= FNAME_MAX)
377				goto err3;
378			gzfname[k++] = c;
379		} while (c);
380		fprintf(stderr, "gzHeader FNAME: %s\n", gzfname);
381	}
382
383	/* FHCRC */
384	if (flg & 0x2) {
385		c = GETINPC(inpf);
386		if (c == EOF)
387			goto err3;
388		c = GETINPC(inpf);
389		if (c == EOF)
390			goto err3;
391		fprintf(stderr, "gzHeader FHCRC: ignored\n");
392	}
393
394	used_in = cur_in = used_out = cur_out = 0;
395	is_final = is_eof = 0;
396
397	/* Allocate one page larger to prevent page faults due to NX
398	 * overfetching.
399	 * Either do this (char*)(uintptr_t)aligned_alloc or use
400	 * -std=c11 flag to make the int-to-pointer warning go away.
401	 */
402	assert((fifo_in  = (char *)(uintptr_t)aligned_alloc(line_sz,
403				   fifo_in_len + page_sz)) != NULL);
404	assert((fifo_out = (char *)(uintptr_t)aligned_alloc(line_sz,
405				   fifo_out_len + page_sz + line_sz)) != NULL);
406	/* Leave unused space due to history rounding rules */
407	fifo_out = fifo_out + line_sz;
408	nxu_touch_pages(fifo_out, fifo_out_len, page_sz, 1);
409
410	ddl_in  = &dde_in[0];
411	ddl_out = &dde_out[0];
412	cmdp = &cmd;
413	memset(&cmdp->crb, 0, sizeof(cmdp->crb));
414
415read_state:
416
417	/* Read from .gz file */
418
419	NXPRT(fprintf(stderr, "read_state:\n"));
420
421	if (is_eof != 0)
422		goto write_state;
423
424	/* We read in to fifo_in in two steps: first: read in to from
425	 * cur_in to the end of the buffer.  last: if free space wrapped
426	 * around, read from fifo_in offset 0 to offset cur_in.
427	 */
428
429	/* Reset fifo head to reduce unnecessary wrap arounds */
430	cur_in = (used_in == 0) ? 0 : cur_in;
431
432	/* Free space total is reduced by a gap */
433	free_space = NX_MAX(0, fifo_free_bytes(used_in, fifo_in_len)
434			    - line_sz);
435
436	/* Free space may wrap around as first and last */
437	first_free = fifo_free_first_bytes(cur_in, used_in, fifo_in_len);
438	last_free  = fifo_free_last_bytes(cur_in, used_in, fifo_in_len);
439
440	/* Start offsets of the free memory */
441	first_offset = fifo_free_first_offset(cur_in, used_in);
442	last_offset  = fifo_free_last_offset(cur_in, used_in, fifo_in_len);
443
444	/* Reduce read_sz because of the line_sz gap */
445	read_sz = NX_MIN(free_space, first_free);
446	n = 0;
447	if (read_sz > 0) {
448		/* Read in to offset cur_in + used_in */
449		n = fread(fifo_in + first_offset, 1, read_sz, inpf);
450		used_in = used_in + n;
451		free_space = free_space - n;
452		assert(n <= read_sz);
453		if (n != read_sz) {
454			/* Either EOF or error; exit the read loop */
455			is_eof = 1;
456			goto write_state;
457		}
458	}
459
460	/* If free space wrapped around */
461	if (last_free > 0) {
462		/* Reduce read_sz because of the line_sz gap */
463		read_sz = NX_MIN(free_space, last_free);
464		n = 0;
465		if (read_sz > 0) {
466			n = fread(fifo_in + last_offset, 1, read_sz, inpf);
467			used_in = used_in + n;       /* Increase used space */
468			free_space = free_space - n; /* Decrease free space */
469			assert(n <= read_sz);
470			if (n != read_sz) {
471				/* Either EOF or error; exit the read loop */
472				is_eof = 1;
473				goto write_state;
474			}
475		}
476	}
477
478	/* At this point we have used_in bytes in fifo_in with the
479	 * data head starting at cur_in and possibly wrapping around.
480	 */
481
482write_state:
483
484	/* Write decompressed data to output file */
485
486	NXPRT(fprintf(stderr, "write_state:\n"));
487
488	if (used_out == 0)
489		goto decomp_state;
490
491	/* If fifo_out has data waiting, write it out to the file to
492	 * make free target space for the accelerator used bytes in
493	 * the first and last parts of fifo_out.
494	 */
495
496	first_used = fifo_used_first_bytes(cur_out, used_out, fifo_out_len);
497	last_used  = fifo_used_last_bytes(cur_out, used_out, fifo_out_len);
498
499	write_sz = first_used;
500
501	n = 0;
502	if (write_sz > 0) {
503		n = fwrite(fifo_out + cur_out, 1, write_sz, outf);
504		used_out = used_out - n;
505		/* Move head of the fifo */
506		cur_out = (cur_out + n) % fifo_out_len;
507		assert(n <= write_sz);
508		if (n != write_sz) {
509			fprintf(stderr, "error: write\n");
510			rc = -1;
511			goto err5;
512		}
513	}
514
515	if (last_used > 0) { /* If more data available in the last part */
516		write_sz = last_used; /* Keep it here for later */
517		n = 0;
518		if (write_sz > 0) {
519			n = fwrite(fifo_out, 1, write_sz, outf);
520			used_out = used_out - n;
521			cur_out = (cur_out + n) % fifo_out_len;
522			assert(n <= write_sz);
523			if (n != write_sz) {
524				fprintf(stderr, "error: write\n");
525				rc = -1;
526				goto err5;
527			}
528		}
529	}
530
531decomp_state:
532
533	/* NX decompresses input data */
534
535	NXPRT(fprintf(stderr, "decomp_state:\n"));
536
537	if (is_final)
538		goto finish_state;
539
540	/* Address/len lists */
541	clearp_dde(ddl_in);
542	clearp_dde(ddl_out);
543
544	/* FC, CRC, HistLen, Table 6-6 */
545	if (resuming) {
546		/* Resuming a partially decompressed input.
547		 * The key to resume is supplying the 32KB
548		 * dictionary (history) to NX, which is basically
549		 * the last 32KB of output produced.
550		 */
551		fc = GZIP_FC_DECOMPRESS_RESUME;
552
553		cmdp->cpb.in_crc   = cmdp->cpb.out_crc;
554		cmdp->cpb.in_adler = cmdp->cpb.out_adler;
555
556		/* Round up the history size to quadword.  Section 2.10 */
557		history_len = (history_len + 15) / 16;
558		putnn(cmdp->cpb, in_histlen, history_len);
559		history_len = history_len * 16; /* bytes */
560
561		if (history_len > 0) {
562			/* Chain in the history buffer to the DDE list */
563			if (cur_out >= history_len) {
564				nx_append_dde(ddl_in, fifo_out
565					      + (cur_out - history_len),
566					      history_len);
567			} else {
568				nx_append_dde(ddl_in, fifo_out
569					      + ((fifo_out_len + cur_out)
570					      - history_len),
571					      history_len - cur_out);
572				/* Up to 32KB history wraps around fifo_out */
573				nx_append_dde(ddl_in, fifo_out, cur_out);
574			}
575
576		}
577	} else {
578		/* First decompress job */
579		fc = GZIP_FC_DECOMPRESS;
580
581		history_len = 0;
582		/* Writing 0 clears out subc as well */
583		cmdp->cpb.in_histlen = 0;
584		total_out = 0;
585
586		put32(cmdp->cpb, in_crc, INIT_CRC);
587		put32(cmdp->cpb, in_adler, INIT_ADLER);
588		put32(cmdp->cpb, out_crc, INIT_CRC);
589		put32(cmdp->cpb, out_adler, INIT_ADLER);
590
591		/* Assuming 10% compression ratio initially; use the
592		 * most recently measured compression ratio as a
593		 * heuristic to estimate the input and output
594		 * sizes.  If we give too much input, the target buffer
595		 * overflows and NX cycles are wasted, and then we
596		 * must retry with smaller input size.  1000 is 100%.
597		 */
598		last_comp_ratio = 100UL;
599	}
600	cmdp->crb.gzip_fc = 0;
601	putnn(cmdp->crb, gzip_fc, fc);
602
603	/*
604	 * NX source buffers
605	 */
606	first_used = fifo_used_first_bytes(cur_in, used_in, fifo_in_len);
607	last_used = fifo_used_last_bytes(cur_in, used_in, fifo_in_len);
608
609	if (first_used > 0)
610		nx_append_dde(ddl_in, fifo_in + cur_in, first_used);
611
612	if (last_used > 0)
613		nx_append_dde(ddl_in, fifo_in, last_used);
614
615	/*
616	 * NX target buffers
617	 */
618	first_free = fifo_free_first_bytes(cur_out, used_out, fifo_out_len);
619	last_free = fifo_free_last_bytes(cur_out, used_out, fifo_out_len);
620
621	/* Reduce output free space amount not to overwrite the history */
622	int target_max = NX_MAX(0, fifo_free_bytes(used_out, fifo_out_len)
623				- (1<<16));
624
625	NXPRT(fprintf(stderr, "target_max %d (0x%x)\n", target_max,
626		      target_max));
627
628	first_free = NX_MIN(target_max, first_free);
629	if (first_free > 0) {
630		first_offset = fifo_free_first_offset(cur_out, used_out);
631		nx_append_dde(ddl_out, fifo_out + first_offset, first_free);
632	}
633
634	if (last_free > 0) {
635		last_free = NX_MIN(target_max - first_free, last_free);
636		if (last_free > 0) {
637			last_offset = fifo_free_last_offset(cur_out, used_out,
638							    fifo_out_len);
639			nx_append_dde(ddl_out, fifo_out + last_offset,
640				      last_free);
641		}
642	}
643
644	/* Target buffer size is used to limit the source data size
645	 * based on previous measurements of compression ratio.
646	 */
647
648	/* source_sz includes history */
649	source_sz = getp32(ddl_in, ddebc);
650	assert(source_sz > history_len);
651	source_sz = source_sz - history_len;
652
653	/* Estimating how much source is needed to 3/4 fill a
654	 * target_max size target buffer.  If we overshoot, then NX
655	 * must repeat the job with smaller input and we waste
656	 * bandwidth.  If we undershoot then we use more NX calls than
657	 * necessary.
658	 */
659
660	source_sz_estimate = ((uint64_t)target_max * last_comp_ratio * 3UL)
661				/ 4000;
662
663	if (source_sz_estimate < source_sz) {
664		/* Target might be small, therefore limiting the
665		 * source data.
666		 */
667		source_sz = source_sz_estimate;
668		target_sz_estimate = target_max;
669	} else {
670		/* Source file might be small, therefore limiting target
671		 * touch pages to a smaller value to save processor cycles.
672		 */
673		target_sz_estimate = ((uint64_t)source_sz * 1000UL)
674					/ (last_comp_ratio + 1);
675		target_sz_estimate = NX_MIN(2 * target_sz_estimate,
676					    target_max);
677	}
678
679	source_sz = source_sz + history_len;
680
681	/* Some NX condition codes require submitting the NX job again.
682	 * Kernel doesn't handle NX page faults. Expects user code to
683	 * touch pages.
684	 */
685	pgfault_retries = NX_MAX_FAULTS;
686
687restart_nx:
688
689	putp32(ddl_in, ddebc, source_sz);
690
691	/* Fault in pages */
692	nxu_touch_pages(cmdp, sizeof(struct nx_gzip_crb_cpb_t), page_sz, 1);
693	nx_touch_pages_dde(ddl_in, 0, page_sz, 0);
694	nx_touch_pages_dde(ddl_out, target_sz_estimate, page_sz, 1);
695
696	/* Send job to NX */
697	cc = nx_submit_job(ddl_in, ddl_out, cmdp, devhandle);
698
699	switch (cc) {
700
701	case ERR_NX_AT_FAULT:
702
703		/* We touched the pages ahead of time.  In the most common case
704		 * we shouldn't be here.  But may be some pages were paged out.
705		 * Kernel should have placed the faulting address to fsaddr.
706		 */
707		NXPRT(fprintf(stderr, "ERR_NX_AT_FAULT %p\n",
708			      (void *)cmdp->crb.csb.fsaddr));
709
710		if (pgfault_retries == NX_MAX_FAULTS) {
711			/* Try once with exact number of pages */
712			--pgfault_retries;
713			goto restart_nx;
714		} else if (pgfault_retries > 0) {
715			/* If still faulting try fewer input pages
716			 * assuming memory outage
717			 */
718			if (source_sz > page_sz)
719				source_sz = NX_MAX(source_sz / 2, page_sz);
720			--pgfault_retries;
721			goto restart_nx;
722		} else {
723			fprintf(stderr, "cannot make progress; too many ");
724			fprintf(stderr, "page fault retries cc= %d\n", cc);
725			rc = -1;
726			goto err5;
727		}
728
729	case ERR_NX_DATA_LENGTH:
730
731		NXPRT(fprintf(stderr, "ERR_NX_DATA_LENGTH; "));
732		NXPRT(fprintf(stderr, "stream may have trailing data\n"));
733
734		/* Not an error in the most common case; it just says
735		 * there is trailing data that we must examine.
736		 *
737		 * CC=3 CE(1)=0 CE(0)=1 indicates partial completion
738		 * Fig.6-7 and Table 6-8.
739		 */
740		nx_ce = get_csb_ce_ms3b(cmdp->crb.csb);
741
742		if (!csb_ce_termination(nx_ce) &&
743		    csb_ce_partial_completion(nx_ce)) {
744			/* Check CPB for more information
745			 * spbc and tpbc are valid
746			 */
747			sfbt = getnn(cmdp->cpb, out_sfbt); /* Table 6-4 */
748			subc = getnn(cmdp->cpb, out_subc); /* Table 6-4 */
749			spbc = get32(cmdp->cpb, out_spbc_decomp);
750			tpbc = get32(cmdp->crb.csb, tpbc);
751			assert(target_max >= tpbc);
752
753			goto ok_cc3; /* not an error */
754		} else {
755			/* History length error when CE(1)=1 CE(0)=0. */
756			rc = -1;
757			fprintf(stderr, "history length error cc= %d\n", cc);
758			goto err5;
759		}
760
761	case ERR_NX_TARGET_SPACE:
762
763		/* Target buffer not large enough; retry smaller input
764		 * data; give at least 1 byte.  SPBC/TPBC are not valid.
765		 */
766		assert(source_sz > history_len);
767		source_sz = ((source_sz - history_len + 2) / 2) + history_len;
768		NXPRT(fprintf(stderr, "ERR_NX_TARGET_SPACE; retry with "));
769		NXPRT(fprintf(stderr, "smaller input data src %d hist %d\n",
770			      source_sz, history_len));
771		goto restart_nx;
772
773	case ERR_NX_OK:
774
775		/* This should not happen for gzip formatted data;
776		 * we need trailing crc and isize
777		 */
778		fprintf(stderr, "ERR_NX_OK\n");
779		spbc = get32(cmdp->cpb, out_spbc_decomp);
780		tpbc = get32(cmdp->crb.csb, tpbc);
781		assert(target_max >= tpbc);
782		assert(spbc >= history_len);
783		source_sz = spbc - history_len;
784		goto offsets_state;
785
786	default:
787		fprintf(stderr, "error: cc= %d\n", cc);
788		rc = -1;
789		goto err5;
790	}
791
792ok_cc3:
793
794	NXPRT(fprintf(stderr, "cc3: sfbt: %x\n", sfbt));
795
796	assert(spbc > history_len);
797	source_sz = spbc - history_len;
798
799	/* Table 6-4: Source Final Block Type (SFBT) describes the
800	 * last processed deflate block and clues the software how to
801	 * resume the next job.  SUBC indicates how many input bits NX
802	 * consumed but did not process.  SPBC indicates how many
803	 * bytes of source were given to the accelerator including
804	 * history bytes.
805	 */
806
807	switch (sfbt) {
808		int dhtlen;
809
810	case 0x0: /* Deflate final EOB received */
811
812		/* Calculating the checksum start position. */
813
814		source_sz = source_sz - subc / 8;
815		is_final = 1;
816		break;
817
818		/* Resume decompression cases are below. Basically
819		 * indicates where NX has suspended and how to resume
820		 * the input stream.
821		 */
822
823	case 0x8: /* Within a literal block; use rembytecount */
824	case 0x9: /* Within a literal block; use rembytecount; bfinal=1 */
825
826		/* Supply the partially processed source byte again */
827		source_sz = source_sz - ((subc + 7) / 8);
828
829		/* SUBC LS 3bits: number of bits in the first source byte need
830		 * to be processed.
831		 * 000 means all 8 bits;  Table 6-3
832		 * Clear subc, histlen, sfbt, rembytecnt, dhtlen
833		 */
834		cmdp->cpb.in_subc = 0;
835		cmdp->cpb.in_sfbt = 0;
836		putnn(cmdp->cpb, in_subc, subc % 8);
837		putnn(cmdp->cpb, in_sfbt, sfbt);
838		putnn(cmdp->cpb, in_rembytecnt, getnn(cmdp->cpb,
839						      out_rembytecnt));
840		break;
841
842	case 0xA: /* Within a FH block; */
843	case 0xB: /* Within a FH block; bfinal=1 */
844
845		source_sz = source_sz - ((subc + 7) / 8);
846
847		/* Clear subc, histlen, sfbt, rembytecnt, dhtlen */
848		cmdp->cpb.in_subc = 0;
849		cmdp->cpb.in_sfbt = 0;
850		putnn(cmdp->cpb, in_subc, subc % 8);
851		putnn(cmdp->cpb, in_sfbt, sfbt);
852		break;
853
854	case 0xC: /* Within a DH block; */
855	case 0xD: /* Within a DH block; bfinal=1 */
856
857		source_sz = source_sz - ((subc + 7) / 8);
858
859		/* Clear subc, histlen, sfbt, rembytecnt, dhtlen */
860		cmdp->cpb.in_subc = 0;
861		cmdp->cpb.in_sfbt = 0;
862		putnn(cmdp->cpb, in_subc, subc % 8);
863		putnn(cmdp->cpb, in_sfbt, sfbt);
864
865		dhtlen = getnn(cmdp->cpb, out_dhtlen);
866		putnn(cmdp->cpb, in_dhtlen, dhtlen);
867		assert(dhtlen >= 42);
868
869		/* Round up to a qword */
870		dhtlen = (dhtlen + 127) / 128;
871
872		while (dhtlen > 0) { /* Copy dht from cpb.out to cpb.in */
873			--dhtlen;
874			cmdp->cpb.in_dht[dhtlen] = cmdp->cpb.out_dht[dhtlen];
875		}
876		break;
877
878	case 0xE: /* Within a block header; bfinal=0; */
879		     /* Also given if source data exactly ends (SUBC=0) with
880		      * EOB code with BFINAL=0.  Means the next byte will
881		      * contain a block header.
882		      */
883	case 0xF: /* within a block header with BFINAL=1. */
884
885		source_sz = source_sz - ((subc + 7) / 8);
886
887		/* Clear subc, histlen, sfbt, rembytecnt, dhtlen */
888		cmdp->cpb.in_subc = 0;
889		cmdp->cpb.in_sfbt = 0;
890		putnn(cmdp->cpb, in_subc, subc % 8);
891		putnn(cmdp->cpb, in_sfbt, sfbt);
892
893		/* Engine did not process any data */
894		if (is_eof && (source_sz == 0))
895			is_final = 1;
896	}
897
898offsets_state:
899
900	/* Adjust the source and target buffer offsets and lengths  */
901
902	NXPRT(fprintf(stderr, "offsets_state:\n"));
903
904	/* Delete input data from fifo_in */
905	used_in = used_in - source_sz;
906	cur_in = (cur_in + source_sz) % fifo_in_len;
907	input_file_offset = input_file_offset + source_sz;
908
909	/* Add output data to fifo_out */
910	used_out = used_out + tpbc;
911
912	assert(used_out <= fifo_out_len);
913
914	total_out = total_out + tpbc;
915
916	/* Deflate history is 32KB max.  No need to supply more
917	 * than 32KB on a resume.
918	 */
919	history_len = (total_out > window_max) ? window_max : total_out;
920
921	/* To estimate expected expansion in the next NX job; 500 means 50%.
922	 * Deflate best case is around 1 to 1000.
923	 */
924	last_comp_ratio = (1000UL * ((uint64_t)source_sz + 1))
925			  / ((uint64_t)tpbc + 1);
926	last_comp_ratio = NX_MAX(NX_MIN(1000UL, last_comp_ratio), 1);
927	NXPRT(fprintf(stderr, "comp_ratio %ld source_sz %d spbc %d tpbc %d\n",
928		      last_comp_ratio, source_sz, spbc, tpbc));
929
930	resuming = 1;
931
932finish_state:
933
934	NXPRT(fprintf(stderr, "finish_state:\n"));
935
936	if (is_final) {
937		if (used_out)
938			goto write_state; /* More data to write out */
939		else if (used_in < 8) {
940			/* Need at least 8 more bytes containing gzip crc
941			 * and isize.
942			 */
943			rc = -1;
944			goto err4;
945		} else {
946			/* Compare checksums and exit */
947			int i;
948			unsigned char tail[8];
949			uint32_t cksum, isize;
950
951			for (i = 0; i < 8; i++)
952				tail[i] = fifo_in[(cur_in + i) % fifo_in_len];
953			fprintf(stderr, "computed checksum %08x isize %08x\n",
954				cmdp->cpb.out_crc, (uint32_t) (total_out
955				% (1ULL<<32)));
956			cksum = ((uint32_t) tail[0] | (uint32_t) tail[1]<<8
957				 | (uint32_t) tail[2]<<16
958				 | (uint32_t) tail[3]<<24);
959			isize = ((uint32_t) tail[4] | (uint32_t) tail[5]<<8
960				 | (uint32_t) tail[6]<<16
961				 | (uint32_t) tail[7]<<24);
962			fprintf(stderr, "stored   checksum %08x isize %08x\n",
963				cksum, isize);
964
965			if (cksum == cmdp->cpb.out_crc && isize == (uint32_t)
966			    (total_out % (1ULL<<32))) {
967				rc = 0;	goto ok1;
968			} else {
969				rc = -1; goto err4;
970			}
971		}
972	} else
973		goto read_state;
974
975	return -1;
976
977err1:
978	fprintf(stderr, "error: not a gzip file, expect %x, read %x\n",
979		expect, c);
980	return -1;
981
982err2:
983	fprintf(stderr, "error: the FLG byte is wrong or not being handled\n");
984	return -1;
985
986err3:
987	fprintf(stderr, "error: gzip header\n");
988	return -1;
989
990err4:
991	fprintf(stderr, "error: checksum missing or mismatch\n");
992
993err5:
994ok1:
995	fprintf(stderr, "decomp is complete: fclose\n");
996	fclose(outf);
997
998	return rc;
999}
1000
1001
1002int main(int argc, char **argv)
1003{
1004	int rc;
1005	struct sigaction act;
1006	void *handle;
1007
1008	nx_dbg = 0;
1009	nx_gzip_log = NULL;
1010	act.sa_handler = 0;
1011	act.sa_sigaction = nxu_sigsegv_handler;
1012	act.sa_flags = SA_SIGINFO;
1013	act.sa_restorer = 0;
1014	sigemptyset(&act.sa_mask);
1015	sigaction(SIGSEGV, &act, NULL);
1016
1017	handle = nx_function_begin(NX_FUNC_COMP_GZIP, 0);
1018	if (!handle) {
1019		fprintf(stderr, "Unable to init NX, errno %d\n", errno);
1020		exit(-1);
1021	}
1022
1023	rc = decompress_file(argc, argv, handle);
1024
1025	nx_function_end(handle);
1026
1027	return rc;
1028}
1029