static struct timeval next_removal_check;
/** Creation time of the snapshot currently being created. */
static int64_t current_snapshot_creation_time;
-/** The snapshot currently being removed. */
+/* Set by the pre-rm hook, cleared by handle_remove_exit(). */
struct snapshot *snapshot_currently_being_removed;
/** Needed by the post-create hook. */
static char *path_to_last_complete_snapshot;
return strcmp(s->name, name_of_reference_snapshot)? 0 : 1;
}
-/*
- * return: 0: no redundant snapshots, 1: rm process started, negative: error
- */
static struct snapshot *find_redundant_snapshot(struct snapshot_list *sl)
{
int i, interval;
int i, num_complete;
struct snapshot *s, *ref = NULL;
+ DSS_DEBUG_LOG(("picking snapshot with earliest creation time\n"));
num_complete = num_complete_snapshots(sl);
if (num_complete <= OPT_UINT32_VAL(DSS, MIN_COMPLETE))
return NULL;
ref = s;
continue;
}
- DSS_INFO_LOG(("oldest removable snapshot: %s\n", s->name));
return s;
}
assert(ref);
return ref;
}
+/* returns NULL <==> *reason is set to NULL */
+static struct snapshot *find_removable_snapshot(struct snapshot_list *sl,
+ bool try_hard, char **reason)
+{
+ struct snapshot *victim;
+
+ /*
+ * Don't remove anything if there is free space and we have fewer
+ * snapshots than configured, plus one. This way there is always one
+ * snapshot that can be recycled.
+ */
+ if (!try_hard && sl->num_snapshots <=
+ 1 << OPT_UINT32_VAL(DSS, NUM_INTERVALS))
+ goto nope;
+ victim = find_orphaned_snapshot(sl);
+ if (victim) {
+ *reason = make_message("orphaned");
+ return victim;
+ }
+ victim = find_outdated_snapshot(sl);
+ if (victim) {
+ *reason = make_message("outdated");
+ return victim;
+ }
+ if (!OPT_GIVEN(DSS, KEEP_REDUNDANT)) {
+ victim = find_redundant_snapshot(sl);
+ if (victim) {
+ *reason = make_message("redundant");
+ return victim;
+ }
+ }
+ if (!try_hard)
+ goto nope;
+ DSS_WARNING_LOG(("nothing obvious to remove\n"));
+ victim = find_oldest_removable_snapshot(sl);
+ if (victim) {
+ *reason = make_message("oldest");
+ return victim;
+ }
+nope:
+ *reason = NULL;
+ return NULL;
+}
+
static int rename_incomplete_snapshot(int64_t start)
{
char *old_name;
struct snapshot_list sl;
struct snapshot *victim;
struct timeval now;
- const char *why;
+ char *why;
int low_disk_space;
ret = disk_space_low(NULL);
if (tv_diff(&next_removal_check, &now, NULL) > 0)
return 0;
if (!low_disk_space) {
- if (OPT_GIVEN(DSS, KEEP_REDUNDANT))
- return 0;
if (snapshot_creation_status != HS_READY)
return 0;
if (next_snapshot_is_due())
return 0;
}
- /*
- * Idle and --keep_redundant not given, or low disk space. Look at
- * existing snapshots.
- */
+ /* Idle or low disk space, look at existing snapshots. */
dss_get_snapshot_list(&sl);
- ret = 0;
- /*
- * Don't remove anything if there is free space and we have fewer
- * snapshots than configured, plus one. This way there is always one
- * snapshot that can be recycled.
- */
- if (!low_disk_space && sl.num_snapshots <=
- 1 << OPT_UINT32_VAL(DSS, NUM_INTERVALS))
- goto out;
- why = "outdated";
- victim = find_outdated_snapshot(&sl);
- if (victim)
- goto remove;
- why = "redundant";
- victim = find_redundant_snapshot(&sl);
- if (victim)
- goto remove;
- why = "orphaned";
- victim = find_orphaned_snapshot(&sl);
+ victim = find_removable_snapshot(&sl, low_disk_space, &why);
+ if (victim) {
+ pre_remove_hook(victim, why);
+ free(why);
+ }
+ free_snapshot_list(&sl);
if (victim)
- goto remove;
- /* try harder only if disk space is low */
+ return 1;
if (!low_disk_space)
- goto out;
- DSS_WARNING_LOG(("disk space low and nothing obvious to remove\n"));
- why = "oldest";
- victim = find_oldest_removable_snapshot(&sl);
- if (victim)
- goto remove;
+ return 0;
DSS_CRIT_LOG(("uhuhu: disk space low and nothing to remove\n"));
- ret = -ERRNO_TO_DSS_ERROR(ENOSPC);
- goto out;
-remove:
- pre_remove_hook(victim, why);
-out:
- free_snapshot_list(&sl);
- return ret;
+ return -ERRNO_TO_DSS_ERROR(ENOSPC);
}
static void post_create_hook(void)
static void create_rsync_argv(char ***argv, int64_t *num)
{
char *logname;
- int i = 0, j, N = OPT_GIVEN(DSS, RSYNC_OPTION);
+ int i = 0, j, N;
struct snapshot_list sl;
static bool seeded;
name_of_reference_snapshot = name_of_newest_complete_snapshot(&sl);
free_snapshot_list(&sl);
- *argv = dss_malloc((15 + N) * sizeof(char *));
+ /*
+ * We specify up to 6 arguments, one argument per given rsync option
+ * and one argument per given source dir. We also need space for the
+ * terminating NULL pointer.
+ */
+ N = OPT_GIVEN(DSS, RSYNC_OPTION) + OPT_GIVEN(DSS, SOURCE_DIR);
+ *argv = dss_malloc((7 + N) * sizeof(char *));
(*argv)[i++] = dss_strdup("rsync");
(*argv)[i++] = dss_strdup("-a");
(*argv)[i++] = dss_strdup("--delete");
DSS_NOTICE_LOG(("adding --checksum to rsync options\n"));
(*argv)[i++] = dss_strdup("--checksum");
}
- for (j = 0; j < N; j++)
+ for (j = 0; j < OPT_GIVEN(DSS, RSYNC_OPTION); j++)
(*argv)[i++] = dss_strdup(lls_string_val(j,
OPT_RESULT(DSS, RSYNC_OPTION)));
if (name_of_reference_snapshot) {
} else
DSS_INFO_LOG(("no suitable reference snapshot found\n"));
logname = dss_logname();
- N = OPT_GIVEN(DSS, SOURCE_DIR);
if (use_rsync_locally(logname)) {
- for (j = 0; j < N; j++)
+ for (j = 0; j < OPT_GIVEN(DSS, SOURCE_DIR); j++)
(*argv)[i++] = dss_strdup(lls_string_val(j,
OPT_RESULT(DSS, SOURCE_DIR)));
} else {
* directory on the destination match the source. To preserve
* the old behaviour, we thus have to special-case N=1.
*/
- for (j = 0; j < N; j++) {
+ for (j = 0; j < OPT_GIVEN(DSS, SOURCE_DIR); j++) {
(*argv)[i++] = make_message("%s@%s:%s%s",
OPT_GIVEN(DSS, REMOTE_USER)?
OPT_STRING_VAL(DSS, REMOTE_USER) : logname,
victim = find_redundant_snapshot(&sl);
if (victim)
goto rm;
+ dss_msg("nothing to prune\n");
ret = 0;
goto out;
rm:
ret = wait_for_remove_process();
if (ret < 0)
goto out;
+ ret = -E_HOOK_FAILED;
if (snapshot_removal_status != HS_PRE_SUCCESS)
goto out;
}
ret = wait_for_remove_process();
if (ret < 0)
goto out;
- if (snapshot_removal_status != HS_SUCCESS)
- goto out;
+ assert(snapshot_removal_status == HS_SUCCESS);
post_remove_hook();
- if (snapshot_removal_status != HS_POST_RUNNING)
- goto out;
+ assert(snapshot_removal_status == HS_POST_RUNNING);
ret = wait_for_remove_process();
if (ret < 0)
goto out;