src/journal/journal-vacuum.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright 2011 Lennart Poettering
   4 ***/
   5
   6 #include <fcntl.h>
   7 #include <sys/stat.h>
   8 #include <unistd.h>
   9
  10 #include "sd-id128.h"
  11
  12 #include "alloc-util.h"
  13 #include "dirent-util.h"
  14 #include "fd-util.h"
  15 #include "fs-util.h"
  16 #include "journal-def.h"
  17 #include "journal-file.h"
  18 #include "journal-vacuum.h"
  19 #include "parse-util.h"
  20 #include "string-util.h"
  21 #include "util.h"
  22 #include "xattr-util.h"
  23
  24 struct vacuum_info {
  25         uint64_t usage;
  26         char *filename;
  27
  28         uint64_t realtime;
  29
  30         sd_id128_t seqnum_id;
  31         uint64_t seqnum;
  32         bool have_seqnum;
  33 };
  34
  35 static int vacuum_compare(const void *_a, const void *_b) {
  36         const struct vacuum_info *a, *b;
  37
  38         a = _a;
  39         b = _b;
  40
  41         if (a->have_seqnum && b->have_seqnum &&
  42             sd_id128_equal(a->seqnum_id, b->seqnum_id)) {
  43                 if (a->seqnum < b->seqnum)
  44                         return -1;
  45                 else if (a->seqnum > b->seqnum)
  46                         return 1;
  47                 else
  48                         return 0;
  49         }
  50
  51         if (a->realtime < b->realtime)
  52                 return -1;
  53         else if (a->realtime > b->realtime)
  54                 return 1;
  55         else if (a->have_seqnum && b->have_seqnum)
  56                 return memcmp(&a->seqnum_id, &b->seqnum_id, 16);
  57         else
  58                 return strcmp(a->filename, b->filename);
  59 }
  60
  61 static void patch_realtime(
  62                 int fd,
  63                 const char *fn,
  64                 const struct stat *st,
  65                 unsigned long long *realtime) {
  66
  67         usec_t x, crtime = 0;
  68
  69         /* The timestamp was determined by the file name, but let's
  70          * see if the file might actually be older than the file name
  71          * suggested... */
  72
  73         assert(fd >= 0);
  74         assert(fn);
  75         assert(st);
  76         assert(realtime);
  77
  78         x = timespec_load(&st->st_ctim);
  79         if (x > 0 && x != USEC_INFINITY && x < *realtime)
  80                 *realtime = x;
  81
  82         x = timespec_load(&st->st_atim);
  83         if (x > 0 && x != USEC_INFINITY && x < *realtime)
  84                 *realtime = x;
  85
  86         x = timespec_load(&st->st_mtim);
  87         if (x > 0 && x != USEC_INFINITY && x < *realtime)
  88                 *realtime = x;
  89
  90         /* Let's read the original creation time, if possible. Ideally
  91          * we'd just query the creation time the FS might provide, but
  92          * unfortunately there's currently no sane API to query
  93          * it. Hence let's implement this manually... */
  94
  95         if (fd_getcrtime_at(fd, fn, &crtime, 0) >= 0) {
  96                 if (crtime < *realtime)
  97                         *realtime = crtime;
  98         }
  99 }
 100
 101 static int journal_file_empty(int dir_fd, const char *name) {
 102         _cleanup_close_ int fd;
 103         struct stat st;
 104         le64_t n_entries;
 105         ssize_t n;
 106
 107         fd = openat(dir_fd, name, O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK|O_NOATIME);
 108         if (fd < 0) {
 109                 /* Maybe failed due to O_NOATIME and lack of privileges? */
 110                 fd = openat(dir_fd, name, O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);
 111                 if (fd < 0)
 112                         return -errno;
 113         }
 114
 115         if (fstat(fd, &st) < 0)
 116                 return -errno;
 117
 118         /* If an offline file doesn't even have a header we consider it empty */
 119         if (st.st_size < (off_t) sizeof(Header))
 120                 return 1;
 121
 122         /* If the number of entries is empty, we consider it empty, too */
 123         n = pread(fd, &n_entries, sizeof(n_entries), offsetof(Header, n_entries));
 124         if (n < 0)
 125                 return -errno;
 126         if (n != sizeof(n_entries))
 127                 return -EIO;
 128
 129         return le64toh(n_entries) <= 0;
 130 }
 131
 132 int journal_directory_vacuum(
 133                 const char *directory,
 134                 uint64_t max_use,
 135                 uint64_t n_max_files,
 136                 usec_t max_retention_usec,
 137                 usec_t *oldest_usec,
 138                 bool verbose) {
 139
 140         _cleanup_closedir_ DIR *d = NULL;
 141         struct vacuum_info *list = NULL;
 142         unsigned n_list = 0, i, n_active_files = 0;
 143         size_t n_allocated = 0;
 144         uint64_t sum = 0, freed = 0;
 145         usec_t retention_limit = 0;
 146         char sbytes[FORMAT_BYTES_MAX];
 147         struct dirent *de;
 148         int r;
 149
 150         assert(directory);
 151
 152         if (max_use <= 0 && max_retention_usec <= 0 && n_max_files <= 0)
 153                 return 0;
 154
 155         if (max_retention_usec > 0) {
 156                 retention_limit = now(CLOCK_REALTIME);
 157                 if (retention_limit > max_retention_usec)
 158                         retention_limit -= max_retention_usec;
 159                 else
 160                         max_retention_usec = retention_limit = 0;
 161         }
 162
 163         d = opendir(directory);
 164         if (!d)
 165                 return -errno;
 166
 167         FOREACH_DIRENT_ALL(de, d, r = -errno; goto finish) {
 168
 169                 unsigned long long seqnum = 0, realtime;
 170                 _cleanup_free_ char *p = NULL;
 171                 sd_id128_t seqnum_id;
 172                 bool have_seqnum;
 173                 uint64_t size;
 174                 struct stat st;
 175                 size_t q;
 176
 177                 if (fstatat(dirfd(d), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0) {
 178                         log_debug_errno(errno, "Failed to stat file %s while vacuuming, ignoring: %m", de->d_name);
 179                         continue;
 180                 }
 181
 182                 if (!S_ISREG(st.st_mode))
 183                         continue;
 184
 185                 q = strlen(de->d_name);
 186
 187                 if (endswith(de->d_name, ".journal")) {
 188
 189                         /* Vacuum archived files. Active files are
 190                          * left around */
 191
 192                         if (q < 1 + 32 + 1 + 16 + 1 + 16 + 8) {
 193                                 n_active_files++;
 194                                 continue;
 195                         }
 196
 197                         if (de->d_name[q-8-16-1] != '-' ||
 198                             de->d_name[q-8-16-1-16-1] != '-' ||
 199                             de->d_name[q-8-16-1-16-1-32-1] != '@') {
 200                                 n_active_files++;
 201                                 continue;
 202                         }
 203
 204                         p = strdup(de->d_name);
 205                         if (!p) {
 206                                 r = -ENOMEM;
 207                                 goto finish;
 208                         }
 209
 210                         de->d_name[q-8-16-1-16-1] = 0;
 211                         if (sd_id128_from_string(de->d_name + q-8-16-1-16-1-32, &seqnum_id) < 0) {
 212                                 n_active_files++;
 213                                 continue;
 214                         }
 215
 216                         if (sscanf(de->d_name + q-8-16-1-16, "%16llx-%16llx.journal", &seqnum, &realtime) != 2) {
 217                                 n_active_files++;
 218                                 continue;
 219                         }
 220
 221                         have_seqnum = true;
 222
 223                 } else if (endswith(de->d_name, ".journal~")) {
 224                         unsigned long long tmp;
 225
 226                         /* Vacuum corrupted files */
 227
 228                         if (q < 1 + 16 + 1 + 16 + 8 + 1) {
 229                                 n_active_files++;
 230                                 continue;
 231                         }
 232
 233                         if (de->d_name[q-1-8-16-1] != '-' ||
 234                             de->d_name[q-1-8-16-1-16-1] != '@') {
 235                                 n_active_files++;
 236                                 continue;
 237                         }
 238
 239                         p = strdup(de->d_name);
 240                         if (!p) {
 241                                 r = -ENOMEM;
 242                                 goto finish;
 243                         }
 244
 245                         if (sscanf(de->d_name + q-1-8-16-1-16, "%16llx-%16llx.journal~", &realtime, &tmp) != 2) {
 246                                 n_active_files++;
 247                                 continue;
 248                         }
 249
 250                         have_seqnum = false;
 251                 } else {
 252                         /* We do not vacuum unknown files! */
 253                         log_debug("Not vacuuming unknown file %s.", de->d_name);
 254                         continue;
 255                 }
 256
 257                 size = 512UL * (uint64_t) st.st_blocks;
 258
 259                 r = journal_file_empty(dirfd(d), p);
 260                 if (r < 0) {
 261                         log_debug_errno(r, "Failed check if %s is empty, ignoring: %m", p);
 262                         continue;
 263                 }
 264                 if (r > 0) {
 265                         /* Always vacuum empty non-online files. */
 266
 267                         r = unlinkat_deallocate(dirfd(d), p, 0);
 268                         if (r >= 0) {
 269
 270                                 log_full(verbose ? LOG_INFO : LOG_DEBUG,
 271                                          "Deleted empty archived journal %s/%s (%s).", directory, p, format_bytes(sbytes, sizeof(sbytes), size));
 272
 273                                 freed += size;
 274                         } else if (r != -ENOENT)
 275                                 log_warning_errno(r, "Failed to delete empty archived journal %s/%s: %m", directory, p);
 276
 277                         continue;
 278                 }
 279
 280                 patch_realtime(dirfd(d), p, &st, &realtime);
 281
 282                 if (!GREEDY_REALLOC(list, n_allocated, n_list + 1)) {
 283                         r = -ENOMEM;
 284                         goto finish;
 285                 }
 286
 287                 list[n_list].filename = TAKE_PTR(p);
 288                 list[n_list].usage = size;
 289                 list[n_list].seqnum = seqnum;
 290                 list[n_list].realtime = realtime;
 291                 list[n_list].seqnum_id = seqnum_id;
 292                 list[n_list].have_seqnum = have_seqnum;
 293                 n_list++;
 294
 295                 sum += size;
 296         }
 297
 298         qsort_safe(list, n_list, sizeof(struct vacuum_info), vacuum_compare);
 299
 300         for (i = 0; i < n_list; i++) {
 301                 unsigned left;
 302
 303                 left = n_active_files + n_list - i;
 304
 305                 if ((max_retention_usec <= 0 || list[i].realtime >= retention_limit) &&
 306                     (max_use <= 0 || sum <= max_use) &&
 307                     (n_max_files <= 0 || left <= n_max_files))
 308                         break;
 309
 310                 r = unlinkat_deallocate(dirfd(d), list[i].filename, 0);
 311                 if (r >= 0) {
 312                         log_full(verbose ? LOG_INFO : LOG_DEBUG, "Deleted archived journal %s/%s (%s).", directory, list[i].filename, format_bytes(sbytes, sizeof(sbytes), list[i].usage));
 313                         freed += list[i].usage;
 314
 315                         if (list[i].usage < sum)
 316                                 sum -= list[i].usage;
 317                         else
 318                                 sum = 0;
 319
 320                 } else if (r != -ENOENT)
 321                         log_warning_errno(r, "Failed to delete archived journal %s/%s: %m", directory, list[i].filename);
 322         }
 323
 324         if (oldest_usec && i < n_list && (*oldest_usec == 0 || list[i].realtime < *oldest_usec))
 325                 *oldest_usec = list[i].realtime;
 326
 327         r = 0;
 328
 329 finish:
 330         for (i = 0; i < n_list; i++)
 331                 free(list[i].filename);
 332         free(list);
 333
 334         log_full(verbose ? LOG_INFO : LOG_DEBUG, "Vacuuming done, freed %s of archived journals from %s.", format_bytes(sbytes, sizeof(sbytes), freed), directory);
 335
 336         return r;
 337 }