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