1 /*-
2  * Copyright (c) 1992 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 char copyright[] =
10 "@(#) Copyright (c) 1992 The Regents of the University of California.\n\
11  All rights reserved.\n";
12 #endif /* not lint */
13 
14 #ifndef lint
15 static char sccsid[] = "@(#)cleanerd.c	5.3 (Berkeley) 08/25/92";
16 #endif /* not lint */
17 
18 #include <sys/param.h>
19 #include <sys/mount.h>
20 #include <sys/time.h>
21 
22 #include <ufs/ufs/dinode.h>
23 #include <ufs/lfs/lfs.h>
24 
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <unistd.h>
28 
29 #include "clean.h"
30 char *special = "cleanerd";
31 
32 struct seglist {
33 	int sl_id;	/* segment number */
34 	int sl_cost; 	/* cleaning cost */
35 	char sl_empty;	/* is segment empty */
36 };
37 
38 struct tossstruct {
39 	struct lfs *lfs;
40 	int seg;
41 };
42 
43 /* function prototypes for system calls; not sure where they should go */
44 int	 lfs_segwait __P((fsid_t, struct timeval *));
45 int	 lfs_segclean __P((fsid_t, u_long));
46 int	 lfs_bmapv __P((fsid_t, BLOCK_INFO *, int));
47 int	 lfs_markv __P((fsid_t, BLOCK_INFO *, int));
48 
49 /* function prototypes */
50 int	 bi_tossold __P((const void *, const void *, const void *));
51 int	 choose_segments __P((FS_INFO *, struct seglist *,
52 	     int (*)(FS_INFO *, SEGUSE *)));
53 void	 clean_fs __P((FS_INFO	*, int (*)(FS_INFO *, SEGUSE *)));
54 int	 clean_loop __P((FS_INFO *));
55 int	 clean_segment __P((FS_INFO *, int));
56 int	 cost_benefit __P((FS_INFO *, SEGUSE *));
57 int	 cost_compare __P((const void *, const void *));
58 
59 /*
60  * Cleaning Cost Functions:
61  *
62  * These return the cost of cleaning a segment.  The higher the cost value
63  * the better it is to clean the segment, so empty segments have the highest
64  * cost.  (It is probably better to think of this as a priority value
65  * instead).
66  *
67  * This is the cost-benefit policy simulated and described in Rosenblum's
68  * 1991 SOSP paper.
69  */
70 
71 int
72 cost_benefit(fsp, su)
73 	FS_INFO *fsp;		/* file system information */
74 	SEGUSE *su;
75 {
76 	struct lfs *lfsp;
77 	struct timeval t;
78 	int age;
79 	int live;
80 
81 	gettimeofday(&t, NULL);
82 
83 	live = su->su_nbytes;
84 	age = t.tv_sec - su->su_lastmod < 0 ? 0 : t.tv_sec - su->su_lastmod;
85 
86 	lfsp = &fsp->fi_lfs;
87 	if (live == 0)
88 		return (t.tv_sec * lblkno(lfsp, seg_size(lfsp)));
89 	else {
90 		/*
91 		 * from lfsSegUsage.c (Mendel's code).
92 		 * priority calculation is done using INTEGER arithmetic.
93 		 * sizes are in BLOCKS (that is why we use lblkno below).
94 		 * age is in seconds.
95 		 *
96 		 * priority = ((seg_size - live) * age) / (seg_size + live)
97 		 */
98 #ifdef VERBOSE
99 		if (live < 0 || live > seg_size(lfsp)) {
100 			err(0, "Bad segusage count: %d", live);
101 			live = 0;
102 		}
103 #endif
104 		return (lblkno(lfsp, seg_size(lfsp) - live) * age)
105 			/ lblkno(lfsp, seg_size(lfsp) + live);
106 	}
107 }
108 
109 int
110 main(argc, argv)
111 	int argc;
112 	char *argv[];
113 {
114 	FS_INFO	*lfp, *fsp;
115 	struct statfs *lstatfsp;	/* file system stats */
116 	struct timeval timeout;		/* sleep timeout */
117 	fsid_t fsid;
118 	int count;			/* number of file systems */
119 	int i, nclean;
120 
121 	count = fs_getmntinfo(&lstatfsp, MOUNT_LFS);
122 
123 	timeout.tv_sec = 5*60; /* five minutes */
124 	timeout.tv_usec = 0;
125 	fsid.val[0] = 0;
126 	fsid.val[1] = 0;
127 
128 	for (fsp = get_fs_info(lstatfsp, count); ; reread_fs_info(fsp, count)) {
129 		for (nclean = 0, lfp = fsp, i = 0; i < count; ++lfp, ++i)
130 			nclean += clean_loop(lfp);
131 		/*
132 		 * If some file systems were actually cleaned, run again
133 		 * to make sure that some nasty process hasn't just
134 		 * filled the disk system up.
135 		 */
136 		if (nclean)
137 			continue;
138 
139 #ifdef VERBOSE
140 		(void)printf("Cleaner going to sleep.\n");
141 #endif
142 		if (lfs_segwait(fsid, &timeout) < 0)
143 			err(0, "lfs_segwait: returned error\n");
144 #ifdef VERBOSE
145 		(void)printf("Cleaner waking up.\n");
146 #endif
147 	}
148 }
149 
150 /* return the number of segments cleaned */
151 int
152 clean_loop(fsp)
153 	FS_INFO	*fsp;	/* file system information */
154 {
155 	double loadavg[MAXLOADS];
156 	time_t	now;
157 	u_long max_free_segs;
158 
159         /*
160 	 * Compute the maximum possible number of free segments, given the
161 	 * number of free blocks.
162 	 */
163 	max_free_segs = fsp->fi_statfsp->f_bfree / fsp->fi_lfs.lfs_ssize;
164 
165 	/*
166 	 * We will clean if there are not enough free blocks or total clean
167 	 * space is less than BUSY_LIM % of possible clean space.
168 	 */
169 	now = time((time_t *)NULL);
170 	if (fsp->fi_cip->clean <= MIN_SEGS(&fsp->fi_lfs) ||
171 	    fsp->fi_cip->clean < max_free_segs * BUSY_LIM) {
172 		printf("Cleaner Running  at %s (need space)\n",
173 		    ctime(&now));
174 		clean_fs(fsp, cost_benefit);
175 		return (1);
176 	} else {
177 	        /*
178 		 * We will also clean if the system is reasonably idle and
179 		 * the total clean space is less then IDLE_LIM % of possible
180 		 * clean space.
181 		 */
182 		if (getloadavg(loadavg, MAXLOADS) == -1) {
183 			perror("getloadavg: failed\n");
184 			return (-1);
185 		}
186 		if (loadavg[ONE_MIN] == 0.0 && loadavg[FIVE_MIN] &&
187 		    fsp->fi_cip->clean < max_free_segs * IDLE_LIM) {
188 		        clean_fs(fsp, cost_benefit);
189 			printf("Cleaner Running  at %s (system idle)\n",
190 			    ctime(&now));
191 			return (1);
192 		}
193 	}
194 	printf("Cleaner Not Running at %s\n", ctime(&now));
195 	return (0);
196 }
197 
198 
199 void
200 clean_fs(fsp, cost_func)
201 	FS_INFO	*fsp;	/* file system information */
202 	int (*cost_func) __P((FS_INFO *, SEGUSE *));
203 {
204 	struct seglist *segs, *sp;
205 	int i;
206 
207 	if ((segs = malloc(fsp->fi_lfs.lfs_nseg * sizeof(struct seglist)))
208 	    == NULL) {
209 		err(0, "malloc failed");
210 		return;
211 	}
212 	i = choose_segments(fsp, segs, cost_func);
213 #ifdef VERBOSE
214 	printf("clean_fs: cleaning %d segments in file system %s\n",
215 		i, fsp->fi_statfsp->f_mntonname);
216 	fflush(stdout);
217 #endif
218 	if (i)
219 		for (i = MIN(i, NUM_TO_CLEAN(fsp)), sp = segs; i-- ; ++sp)
220 			if (clean_segment(fsp, sp->sl_id) < 0)
221 				perror("clean_segment failed");
222 			else if (lfs_segclean (fsp->fi_statfsp->f_fsid,
223 			    sp->sl_id) < 0)
224 				perror("lfs_segclean failed");
225 	free(segs);
226 }
227 
228 /*
229  * Segment with the highest priority get sorted to the beginning of the
230  * list.  This sort assumes that empty segments always have a higher
231  * cost/benefit than any utilized segment.
232  */
233 int
234 cost_compare(a, b)
235 	const void *a;
236 	const void *b;
237 {
238 	return (((struct seglist *)b)->sl_cost -
239 	    ((struct seglist *)a)->sl_cost);
240 }
241 
242 
243 /*
244  * Returns the number of segments to be cleaned with the elements of seglist
245  * filled in.
246  */
247 int
248 choose_segments(fsp, seglist, cost_func)
249 	FS_INFO *fsp;
250 	struct seglist *seglist;
251 	int (*cost_func) __P((FS_INFO *, SEGUSE *));
252 {
253 	struct lfs *lfsp;
254 	struct seglist *sp;
255 	SEGUSE *sup;
256 	int i, nsegs;
257 
258 	lfsp = &fsp->fi_lfs;
259 
260 #ifdef VERBOSE
261 	(void) printf("Entering choose_segments\n");
262 #endif
263 	dump_super(lfsp);
264 	dump_cleaner_info(fsp->fi_cip);
265 
266 	for (sp = seglist, i = 0; i < lfsp->lfs_nseg; ++i) {
267 		sup = SEGUSE_ENTRY(lfsp, fsp->fi_segusep, i);
268 		 PRINT_SEGUSE(sup, i);
269 		if (!(sup->su_flags & SEGUSE_DIRTY) ||
270 		    sup->su_flags & SEGUSE_ACTIVE)
271 			continue;
272 #ifdef VERBOSE
273 		(void) printf("\tchoosing segment %d\n", i);
274 #endif
275 		sp->sl_cost = (*cost_func)(fsp, sup);
276 		sp->sl_id = i;
277 		sp->sl_empty = sup->su_nbytes ? 0 : 1;
278 		++sp;
279 	}
280 	nsegs = sp - seglist;
281 	qsort(seglist, nsegs, sizeof(struct seglist), cost_compare);
282 #ifdef VERBOSE
283 	(void)printf("Returning %d segments\n", nsegs);
284 #endif
285 	return (nsegs);
286 }
287 
288 
289 int
290 clean_segment(fsp, id)
291 	FS_INFO *fsp;	/* file system information */
292 	int id;		/* segment number */
293 {
294 	BLOCK_INFO *block_array;
295 	SEGUSE *sp;
296 	struct lfs *lfsp;
297 	struct tossstruct t;
298 	caddr_t seg_buf;
299 	int num_blocks;
300 
301 	lfsp = &fsp->fi_lfs;
302 	sp = SEGUSE_ENTRY(lfsp, fsp->fi_segusep, id);
303 
304 #ifdef VERBOSE
305 	(void) printf("cleaning segment %d: contains %lu bytes\n", id,
306 	    sp->su_nbytes);
307 	fflush(stdout);
308 #endif
309 	/* XXX could add debugging to verify that segment is really empty */
310 	if (sp->su_nbytes == sp->su_nsums * LFS_SUMMARY_SIZE)
311 		return (0);
312 
313 	/* map the segment into a buffer */
314 	if (mmap_segment(fsp, id, &seg_buf) < 0) {
315 		err(0, "mmap_segment failed");
316 		return (-1);
317 	}
318 	/* get a list of blocks that are contained by the segment */
319 	if (lfs_segmapv(fsp, id, seg_buf, &block_array, &num_blocks) < 0) {
320 		err(0, "clean_segment: lfs_segmapv failed");
321 		return (-1);
322 	}
323 
324 #ifdef VERBOSE
325 	(void) printf("lfs_segmapv returned %d blocks\n", num_blocks);
326 	fflush (stdout);
327 #endif
328 
329 	/* get the current disk address of blocks contained by the segment */
330 	if (lfs_bmapv(fsp->fi_statfsp->f_fsid, block_array, num_blocks) < 0) {
331 		perror("clean_segment: lfs_bmapv failed\n");
332 		return -1;
333 	}
334 
335 	/* Now toss any blocks not in the current segment */
336 	t.lfs = lfsp;
337 	t.seg = id;
338 	toss(block_array, &num_blocks, sizeof(BLOCK_INFO), bi_tossold, &t);
339 
340 	/* Check if last element should be tossed */
341 	if (num_blocks && bi_tossold(&t, block_array + num_blocks - 1, NULL))
342 		--num_blocks;
343 
344 #ifdef VERBOSE
345 	{
346 		BLOCK_INFO *_bip;
347 		u_long *lp;
348 		int i;
349 
350 		(void) printf("after bmapv still have %d blocks\n", num_blocks);
351 		fflush (stdout);
352 		if (num_blocks)
353 			printf("BLOCK INFOS\n");
354 		for (_bip = block_array, i=0; i < num_blocks; ++_bip, ++i) {
355 			PRINT_BINFO(_bip);
356 			lp = (u_long *)_bip->bi_bp;
357 		}
358 	}
359 #endif
360 	/* rewrite the live data */
361 	if (num_blocks > 0)
362 		if (lfs_markv(fsp->fi_statfsp->f_fsid, block_array, num_blocks)
363 		    < 0 ) {
364 			err(0, "clean_segment: lfs_bmapv failed");
365 			return (-1);
366 		}
367 	free(block_array);
368 	munmap_segment(fsp, seg_buf);
369 
370 	return (0);
371 }
372 
373 
374 int
375 bi_tossold(client, a, b)
376 	const void *client;
377 	const void *a;
378 	const void *b;
379 {
380 	const struct tossstruct *t;
381 
382 	t = (struct tossstruct *)client;
383 
384 	return (((BLOCK_INFO *)a)->bi_daddr == LFS_UNUSED_DADDR ||
385 	    datosn(t->lfs, ((BLOCK_INFO *)a)->bi_daddr) != t->seg);
386 }
387