src/journal/journal-vacuum.c

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