| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <fcntl.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.h" |
| #include "bus-common-errors.h" |
| #include "bus-error.h" |
| #include "dbus-unit.h" |
| #include "strv.h" |
| #include "terminal-util.h" |
| #include "transaction.h" |
| |
| static void transaction_unlink_job(Transaction *tr, Job *j, bool delete_dependencies); |
| |
| static void transaction_delete_job(Transaction *tr, Job *j, bool delete_dependencies) { |
| assert(tr); |
| assert(j); |
| |
| /* Deletes one job from the transaction */ |
| |
| transaction_unlink_job(tr, j, delete_dependencies); |
| |
| job_free(j); |
| } |
| |
| static void transaction_delete_unit(Transaction *tr, Unit *u) { |
| Job *j; |
| |
| /* Deletes all jobs associated with a certain unit from the |
| * transaction */ |
| |
| while ((j = hashmap_get(tr->jobs, u))) |
| transaction_delete_job(tr, j, true); |
| } |
| |
| void transaction_abort(Transaction *tr) { |
| Job *j; |
| |
| assert(tr); |
| |
| while ((j = hashmap_first(tr->jobs))) |
| transaction_delete_job(tr, j, false); |
| |
| assert(hashmap_isempty(tr->jobs)); |
| } |
| |
| static void transaction_find_jobs_that_matter_to_anchor(Job *j, unsigned generation) { |
| JobDependency *l; |
| |
| /* A recursive sweep through the graph that marks all units |
| * that matter to the anchor job, i.e. are directly or |
| * indirectly a dependency of the anchor job via paths that |
| * are fully marked as mattering. */ |
| |
| j->matters_to_anchor = true; |
| j->generation = generation; |
| |
| LIST_FOREACH(subject, l, j->subject_list) { |
| |
| /* This link does not matter */ |
| if (!l->matters) |
| continue; |
| |
| /* This unit has already been marked */ |
| if (l->object->generation == generation) |
| continue; |
| |
| transaction_find_jobs_that_matter_to_anchor(l->object, generation); |
| } |
| } |
| |
| static void transaction_merge_and_delete_job(Transaction *tr, Job *j, Job *other, JobType t) { |
| JobDependency *l, *last; |
| |
| assert(j); |
| assert(other); |
| assert(j->unit == other->unit); |
| assert(!j->installed); |
| |
| /* Merges 'other' into 'j' and then deletes 'other'. */ |
| |
| j->type = t; |
| j->state = JOB_WAITING; |
| j->irreversible = j->irreversible || other->irreversible; |
| j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor; |
| |
| /* Patch us in as new owner of the JobDependency objects */ |
| last = NULL; |
| LIST_FOREACH(subject, l, other->subject_list) { |
| assert(l->subject == other); |
| l->subject = j; |
| last = l; |
| } |
| |
| /* Merge both lists */ |
| if (last) { |
| last->subject_next = j->subject_list; |
| if (j->subject_list) |
| j->subject_list->subject_prev = last; |
| j->subject_list = other->subject_list; |
| } |
| |
| /* Patch us in as new owner of the JobDependency objects */ |
| last = NULL; |
| LIST_FOREACH(object, l, other->object_list) { |
| assert(l->object == other); |
| l->object = j; |
| last = l; |
| } |
| |
| /* Merge both lists */ |
| if (last) { |
| last->object_next = j->object_list; |
| if (j->object_list) |
| j->object_list->object_prev = last; |
| j->object_list = other->object_list; |
| } |
| |
| /* Kill the other job */ |
| other->subject_list = NULL; |
| other->object_list = NULL; |
| transaction_delete_job(tr, other, true); |
| } |
| |
| _pure_ static bool job_is_conflicted_by(Job *j) { |
| JobDependency *l; |
| |
| assert(j); |
| |
| /* Returns true if this job is pulled in by a least one |
| * ConflictedBy dependency. */ |
| |
| LIST_FOREACH(object, l, j->object_list) |
| if (l->conflicts) |
| return true; |
| |
| return false; |
| } |
| |
| static int delete_one_unmergeable_job(Transaction *tr, Job *j) { |
| Job *k; |
| |
| assert(j); |
| |
| /* Tries to delete one item in the linked list |
| * j->transaction_next->transaction_next->... that conflicts |
| * with another one, in an attempt to make an inconsistent |
| * transaction work. */ |
| |
| /* We rely here on the fact that if a merged with b does not |
| * merge with c, either a or b merge with c neither */ |
| LIST_FOREACH(transaction, j, j) |
| LIST_FOREACH(transaction, k, j->transaction_next) { |
| Job *d; |
| |
| /* Is this one mergeable? Then skip it */ |
| if (job_type_is_mergeable(j->type, k->type)) |
| continue; |
| |
| /* Ok, we found two that conflict, let's see if we can |
| * drop one of them */ |
| if (!j->matters_to_anchor && !k->matters_to_anchor) { |
| |
| /* Both jobs don't matter, so let's |
| * find the one that is smarter to |
| * remove. Let's think positive and |
| * rather remove stops then starts -- |
| * except if something is being |
| * stopped because it is conflicted by |
| * another unit in which case we |
| * rather remove the start. */ |
| |
| log_unit_debug(j->unit, |
| "Looking at job %s/%s conflicted_by=%s", |
| j->unit->id, job_type_to_string(j->type), |
| yes_no(j->type == JOB_STOP && job_is_conflicted_by(j))); |
| log_unit_debug(k->unit, |
| "Looking at job %s/%s conflicted_by=%s", |
| k->unit->id, job_type_to_string(k->type), |
| yes_no(k->type == JOB_STOP && job_is_conflicted_by(k))); |
| |
| if (j->type == JOB_STOP) { |
| |
| if (job_is_conflicted_by(j)) |
| d = k; |
| else |
| d = j; |
| |
| } else if (k->type == JOB_STOP) { |
| |
| if (job_is_conflicted_by(k)) |
| d = j; |
| else |
| d = k; |
| } else |
| d = j; |
| |
| } else if (!j->matters_to_anchor) |
| d = j; |
| else if (!k->matters_to_anchor) |
| d = k; |
| else |
| return -ENOEXEC; |
| |
| /* Ok, we can drop one, so let's do so. */ |
| log_unit_debug(d->unit, |
| "Fixing conflicting jobs %s/%s,%s/%s by deleting job %s/%s", |
| j->unit->id, job_type_to_string(j->type), |
| k->unit->id, job_type_to_string(k->type), |
| d->unit->id, job_type_to_string(d->type)); |
| transaction_delete_job(tr, d, true); |
| return 0; |
| } |
| |
| return -EINVAL; |
| } |
| |
| static int transaction_merge_jobs(Transaction *tr, sd_bus_error *e) { |
| Job *j; |
| int r; |
| |
| assert(tr); |
| |
| /* First step, check whether any of the jobs for one specific |
| * task conflict. If so, try to drop one of them. */ |
| HASHMAP_FOREACH(j, tr->jobs) { |
| JobType t; |
| Job *k; |
| |
| t = j->type; |
| LIST_FOREACH(transaction, k, j->transaction_next) { |
| if (job_type_merge_and_collapse(&t, k->type, j->unit) >= 0) |
| continue; |
| |
| /* OK, we could not merge all jobs for this |
| * action. Let's see if we can get rid of one |
| * of them */ |
| |
| r = delete_one_unmergeable_job(tr, j); |
| if (r >= 0) |
| /* Ok, we managed to drop one, now |
| * let's ask our callers to call us |
| * again after garbage collecting */ |
| return -EAGAIN; |
| |
| /* We couldn't merge anything. Failure */ |
| return sd_bus_error_setf(e, BUS_ERROR_TRANSACTION_JOBS_CONFLICTING, |
| "Transaction contains conflicting jobs '%s' and '%s' for %s. " |
| "Probably contradicting requirement dependencies configured.", |
| job_type_to_string(t), |
| job_type_to_string(k->type), |
| k->unit->id); |
| } |
| } |
| |
| /* Second step, merge the jobs. */ |
| HASHMAP_FOREACH(j, tr->jobs) { |
| JobType t = j->type; |
| Job *k; |
| |
| /* Merge all transaction jobs for j->unit */ |
| LIST_FOREACH(transaction, k, j->transaction_next) |
| assert_se(job_type_merge_and_collapse(&t, k->type, j->unit) == 0); |
| |
| while ((k = j->transaction_next)) { |
| if (tr->anchor_job == k) { |
| transaction_merge_and_delete_job(tr, k, j, t); |
| j = k; |
| } else |
| transaction_merge_and_delete_job(tr, j, k, t); |
| } |
| |
| assert(!j->transaction_next); |
| assert(!j->transaction_prev); |
| } |
| |
| return 0; |
| } |
| |
| static void transaction_drop_redundant(Transaction *tr) { |
| bool again; |
| |
| /* Goes through the transaction and removes all jobs of the units whose jobs are all noops. If not |
| * all of a unit's jobs are redundant, they are kept. */ |
| |
| assert(tr); |
| |
| do { |
| Job *j; |
| |
| again = false; |
| |
| HASHMAP_FOREACH(j, tr->jobs) { |
| bool keep = false; |
| Job *k; |
| |
| LIST_FOREACH(transaction, k, j) |
| if (tr->anchor_job == k || |
| !job_type_is_redundant(k->type, unit_active_state(k->unit)) || |
| (k->unit->job && job_type_is_conflicting(k->type, k->unit->job->type))) { |
| keep = true; |
| break; |
| } |
| |
| if (!keep) { |
| log_trace("Found redundant job %s/%s, dropping from transaction.", |
| j->unit->id, job_type_to_string(j->type)); |
| transaction_delete_job(tr, j, false); |
| again = true; |
| break; |
| } |
| } |
| } while (again); |
| } |
| |
| _pure_ static bool unit_matters_to_anchor(Unit *u, Job *j) { |
| assert(u); |
| assert(!j->transaction_prev); |
| |
| /* Checks whether at least one of the jobs for this unit |
| * matters to the anchor. */ |
| |
| LIST_FOREACH(transaction, j, j) |
| if (j->matters_to_anchor) |
| return true; |
| |
| return false; |
| } |
| |
| static char* merge_unit_ids(const char* unit_log_field, char **pairs) { |
| char **unit_id, **job_type, *ans = NULL; |
| size_t size = 0, next; |
| |
| STRV_FOREACH_PAIR(unit_id, job_type, pairs) { |
| next = strlen(unit_log_field) + strlen(*unit_id); |
| if (!GREEDY_REALLOC(ans, size + next + 1)) |
| return mfree(ans); |
| |
| sprintf(ans + size, "%s%s", unit_log_field, *unit_id); |
| if (*(unit_id+1)) |
| ans[size + next] = '\n'; |
| size += next + 1; |
| } |
| |
| return ans; |
| } |
| |
| static int transaction_verify_order_one(Transaction *tr, Job *j, Job *from, unsigned generation, sd_bus_error *e) { |
| |
| static const UnitDependencyAtom directions[] = { |
| UNIT_ATOM_BEFORE, |
| UNIT_ATOM_AFTER, |
| }; |
| |
| int r; |
| |
| assert(tr); |
| assert(j); |
| assert(!j->transaction_prev); |
| |
| /* Does a recursive sweep through the ordering graph, looking for a cycle. If we find a cycle we try |
| * to break it. */ |
| |
| /* Have we seen this before? */ |
| if (j->generation == generation) { |
| Job *k, *delete = NULL; |
| _cleanup_free_ char **array = NULL, *unit_ids = NULL; |
| char **unit_id, **job_type; |
| |
| /* If the marker is NULL we have been here already and decided the job was loop-free from |
| * here. Hence shortcut things and return right-away. */ |
| if (!j->marker) |
| return 0; |
| |
| /* So, the marker is not NULL and we already have been here. We have a cycle. Let's try to |
| * break it. We go backwards in our path and try to find a suitable job to remove. We use the |
| * marker to find our way back, since smart how we are we stored our way back in there. */ |
| for (k = from; k; k = ((k->generation == generation && k->marker != k) ? k->marker : NULL)) { |
| |
| /* For logging below */ |
| if (strv_push_pair(&array, k->unit->id, (char*) job_type_to_string(k->type)) < 0) |
| log_oom(); |
| |
| if (!delete && hashmap_get(tr->jobs, k->unit) && !unit_matters_to_anchor(k->unit, k)) |
| /* Ok, we can drop this one, so let's do so. */ |
| delete = k; |
| |
| /* Check if this in fact was the beginning of the cycle */ |
| if (k == j) |
| break; |
| } |
| |
| unit_ids = merge_unit_ids(j->manager->unit_log_field, array); /* ignore error */ |
| |
| STRV_FOREACH_PAIR(unit_id, job_type, array) |
| /* logging for j not k here to provide a consistent narrative */ |
| log_struct(LOG_WARNING, |
| "MESSAGE=%s: Found %s on %s/%s", |
| j->unit->id, |
| unit_id == array ? "ordering cycle" : "dependency", |
| *unit_id, *job_type, |
| "%s", unit_ids); |
| |
| if (delete) { |
| const char *status; |
| /* logging for j not k here to provide a consistent narrative */ |
| log_struct(LOG_ERR, |
| "MESSAGE=%s: Job %s/%s deleted to break ordering cycle starting with %s/%s", |
| j->unit->id, delete->unit->id, job_type_to_string(delete->type), |
| j->unit->id, job_type_to_string(j->type), |
| "%s", unit_ids); |
| |
| if (log_get_show_color()) |
| status = ANSI_HIGHLIGHT_RED " SKIP " ANSI_NORMAL; |
| else |
| status = " SKIP "; |
| |
| unit_status_printf(delete->unit, |
| STATUS_TYPE_NOTICE, |
| status, |
| "Ordering cycle found, skipping %s", |
| unit_status_string(delete->unit, NULL)); |
| transaction_delete_unit(tr, delete->unit); |
| return -EAGAIN; |
| } |
| |
| log_struct(LOG_ERR, |
| "MESSAGE=%s: Unable to break cycle starting with %s/%s", |
| j->unit->id, j->unit->id, job_type_to_string(j->type), |
| "%s", unit_ids); |
| |
| return sd_bus_error_setf(e, BUS_ERROR_TRANSACTION_ORDER_IS_CYCLIC, |
| "Transaction order is cyclic. See system logs for details."); |
| } |
| |
| /* Make the marker point to where we come from, so that we can |
| * find our way backwards if we want to break a cycle. We use |
| * a special marker for the beginning: we point to |
| * ourselves. */ |
| j->marker = from ? from : j; |
| j->generation = generation; |
| |
| /* Actual ordering of jobs depends on the unit ordering dependency and job types. We need to traverse |
| * the graph over 'before' edges in the actual job execution order. We traverse over both unit |
| * ordering dependencies and we test with job_compare() whether it is the 'before' edge in the job |
| * execution ordering. */ |
| for (size_t d = 0; d < ELEMENTSOF(directions); d++) { |
| Unit *u; |
| |
| UNIT_FOREACH_DEPENDENCY(u, j->unit, directions[d]) { |
| Job *o; |
| |
| /* Is there a job for this unit? */ |
| o = hashmap_get(tr->jobs, u); |
| if (!o) { |
| /* Ok, there is no job for this in the transaction, but maybe there is |
| * already one running? */ |
| o = u->job; |
| if (!o) |
| continue; |
| } |
| |
| /* Cut traversing if the job j is not really *before* o. */ |
| if (job_compare(j, o, directions[d]) >= 0) |
| continue; |
| |
| r = transaction_verify_order_one(tr, o, j, generation, e); |
| if (r < 0) |
| return r; |
| } |
| } |
| |
| /* Ok, let's backtrack, and remember that this entry is not on |
| * our path anymore. */ |
| j->marker = NULL; |
| |
| return 0; |
| } |
| |
| static int transaction_verify_order(Transaction *tr, unsigned *generation, sd_bus_error *e) { |
| Job *j; |
| int r; |
| unsigned g; |
| |
| assert(tr); |
| assert(generation); |
| |
| /* Check if the ordering graph is cyclic. If it is, try to fix |
| * that up by dropping one of the jobs. */ |
| |
| g = (*generation)++; |
| |
| HASHMAP_FOREACH(j, tr->jobs) { |
| r = transaction_verify_order_one(tr, j, NULL, g, e); |
| if (r < 0) |
| return r; |
| } |
| |
| return 0; |
| } |
| |
| static void transaction_collect_garbage(Transaction *tr) { |
| bool again; |
| |
| assert(tr); |
| |
| /* Drop jobs that are not required by any other job */ |
| |
| do { |
| Job *j; |
| |
| again = false; |
| |
| HASHMAP_FOREACH(j, tr->jobs) { |
| if (tr->anchor_job == j) |
| continue; |
| |
| if (!j->object_list) { |
| log_trace("Garbage collecting job %s/%s", j->unit->id, job_type_to_string(j->type)); |
| transaction_delete_job(tr, j, true); |
| again = true; |
| break; |
| } |
| |
| log_trace("Keeping job %s/%s because of %s/%s", |
| j->unit->id, job_type_to_string(j->type), |
| j->object_list->subject ? j->object_list->subject->unit->id : "root", |
| j->object_list->subject ? job_type_to_string(j->object_list->subject->type) : "root"); |
| } |
| |
| } while (again); |
| } |
| |
| static int transaction_is_destructive(Transaction *tr, JobMode mode, sd_bus_error *e) { |
| Job *j; |
| |
| assert(tr); |
| |
| /* Checks whether applying this transaction means that |
| * existing jobs would be replaced */ |
| |
| HASHMAP_FOREACH(j, tr->jobs) { |
| |
| /* Assume merged */ |
| assert(!j->transaction_prev); |
| assert(!j->transaction_next); |
| |
| if (j->unit->job && (mode == JOB_FAIL || j->unit->job->irreversible) && |
| job_type_is_conflicting(j->unit->job->type, j->type)) |
| return sd_bus_error_setf(e, BUS_ERROR_TRANSACTION_IS_DESTRUCTIVE, |
| "Transaction for %s/%s is destructive (%s has '%s' job queued, but '%s' is included in transaction).", |
| tr->anchor_job->unit->id, job_type_to_string(tr->anchor_job->type), |
| j->unit->id, job_type_to_string(j->unit->job->type), job_type_to_string(j->type)); |
| } |
| |
| return 0; |
| } |
| |
| static void transaction_minimize_impact(Transaction *tr) { |
| Job *j; |
| |
| assert(tr); |
| |
| /* Drops all unnecessary jobs that reverse already active jobs |
| * or that stop a running service. */ |
| |
| rescan: |
| HASHMAP_FOREACH(j, tr->jobs) { |
| LIST_FOREACH(transaction, j, j) { |
| bool stops_running_service, changes_existing_job; |
| |
| /* If it matters, we shouldn't drop it */ |
| if (j->matters_to_anchor) |
| continue; |
| |
| /* Would this stop a running service? |
| * Would this change an existing job? |
| * If so, let's drop this entry */ |
| |
| stops_running_service = |
| j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit)); |
| |
| changes_existing_job = |
| j->unit->job && |
| job_type_is_conflicting(j->type, j->unit->job->type); |
| |
| if (!stops_running_service && !changes_existing_job) |
| continue; |
| |
| if (stops_running_service) |
| log_unit_debug(j->unit, |
| "%s/%s would stop a running service.", |
| j->unit->id, job_type_to_string(j->type)); |
| |
| if (changes_existing_job) |
| log_unit_debug(j->unit, |
| "%s/%s would change existing job.", |
| j->unit->id, job_type_to_string(j->type)); |
| |
| /* Ok, let's get rid of this */ |
| log_unit_debug(j->unit, |
| "Deleting %s/%s to minimize impact.", |
| j->unit->id, job_type_to_string(j->type)); |
| |
| transaction_delete_job(tr, j, true); |
| goto rescan; |
| } |
| } |
| } |
| |
| static int transaction_apply( |
| Transaction *tr, |
| Manager *m, |
| JobMode mode, |
| Set *affected_jobs) { |
| |
| Job *j; |
| int r; |
| |
| /* Moves the transaction jobs to the set of active jobs */ |
| |
| if (IN_SET(mode, JOB_ISOLATE, JOB_FLUSH)) { |
| |
| /* When isolating first kill all installed jobs which |
| * aren't part of the new transaction */ |
| HASHMAP_FOREACH(j, m->jobs) { |
| assert(j->installed); |
| |
| if (j->unit->ignore_on_isolate) |
| continue; |
| |
| if (hashmap_get(tr->jobs, j->unit)) |
| continue; |
| |
| /* Not invalidating recursively. Avoids triggering |
| * OnFailure= actions of dependent jobs. Also avoids |
| * invalidating our iterator. */ |
| job_finish_and_invalidate(j, JOB_CANCELED, false, false); |
| } |
| } |
| |
| HASHMAP_FOREACH(j, tr->jobs) { |
| /* Assume merged */ |
| assert(!j->transaction_prev); |
| assert(!j->transaction_next); |
| |
| r = hashmap_ensure_put(&m->jobs, NULL, UINT32_TO_PTR(j->id), j); |
| if (r < 0) |
| goto rollback; |
| } |
| |
| while ((j = hashmap_steal_first(tr->jobs))) { |
| Job *installed_job; |
| |
| /* Clean the job dependencies */ |
| transaction_unlink_job(tr, j, false); |
| |
| installed_job = job_install(j); |
| if (installed_job != j) { |
| /* j has been merged into a previously installed job */ |
| if (tr->anchor_job == j) |
| tr->anchor_job = installed_job; |
| hashmap_remove(m->jobs, UINT32_TO_PTR(j->id)); |
| job_free(j); |
| j = installed_job; |
| } |
| |
| job_add_to_run_queue(j); |
| job_add_to_dbus_queue(j); |
| job_start_timer(j, false); |
| job_shutdown_magic(j); |
| |
| /* When 'affected' is specified, let's track all in it all jobs that were touched because of |
| * this transaction. */ |
| if (affected_jobs) |
| (void) set_put(affected_jobs, j); |
| } |
| |
| return 0; |
| |
| rollback: |
| |
| HASHMAP_FOREACH(j, tr->jobs) |
| hashmap_remove(m->jobs, UINT32_TO_PTR(j->id)); |
| |
| return r; |
| } |
| |
| int transaction_activate( |
| Transaction *tr, |
| Manager *m, |
| JobMode mode, |
| Set *affected_jobs, |
| sd_bus_error *e) { |
| |
| Job *j; |
| int r; |
| unsigned generation = 1; |
| |
| assert(tr); |
| |
| /* This applies the changes recorded in tr->jobs to |
| * the actual list of jobs, if possible. */ |
| |
| /* Reset the generation counter of all installed jobs. The detection of cycles |
| * looks at installed jobs. If they had a non-zero generation from some previous |
| * walk of the graph, the algorithm would break. */ |
| HASHMAP_FOREACH(j, m->jobs) |
| j->generation = 0; |
| |
| /* First step: figure out which jobs matter */ |
| transaction_find_jobs_that_matter_to_anchor(tr->anchor_job, generation++); |
| |
| /* Second step: Try not to stop any running services if |
| * we don't have to. Don't try to reverse running |
| * jobs if we don't have to. */ |
| if (mode == JOB_FAIL) |
| transaction_minimize_impact(tr); |
| |
| /* Third step: Drop redundant jobs */ |
| transaction_drop_redundant(tr); |
| |
| for (;;) { |
| /* Fourth step: Let's remove unneeded jobs that might |
| * be lurking. */ |
| if (mode != JOB_ISOLATE) |
| transaction_collect_garbage(tr); |
| |
| /* Fifth step: verify order makes sense and correct |
| * cycles if necessary and possible */ |
| r = transaction_verify_order(tr, &generation, e); |
| if (r >= 0) |
| break; |
| |
| if (r != -EAGAIN) |
| return log_warning_errno(r, "Requested transaction contains an unfixable cyclic ordering dependency: %s", bus_error_message(e, r)); |
| |
| /* Let's see if the resulting transaction ordering |
| * graph is still cyclic... */ |
| } |
| |
| for (;;) { |
| /* Sixth step: let's drop unmergeable entries if |
| * necessary and possible, merge entries we can |
| * merge */ |
| r = transaction_merge_jobs(tr, e); |
| if (r >= 0) |
| break; |
| |
| if (r != -EAGAIN) |
| return log_warning_errno(r, "Requested transaction contains unmergeable jobs: %s", bus_error_message(e, r)); |
| |
| /* Seventh step: an entry got dropped, let's garbage |
| * collect its dependencies. */ |
| if (mode != JOB_ISOLATE) |
| transaction_collect_garbage(tr); |
| |
| /* Let's see if the resulting transaction still has |
| * unmergeable entries ... */ |
| } |
| |
| /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */ |
| transaction_drop_redundant(tr); |
| |
| /* Ninth step: check whether we can actually apply this */ |
| r = transaction_is_destructive(tr, mode, e); |
| if (r < 0) |
| return log_notice_errno(r, "Requested transaction contradicts existing jobs: %s", bus_error_message(e, r)); |
| |
| /* Tenth step: apply changes */ |
| r = transaction_apply(tr, m, mode, affected_jobs); |
| if (r < 0) |
| return log_warning_errno(r, "Failed to apply transaction: %m"); |
| |
| assert(hashmap_isempty(tr->jobs)); |
| |
| if (!hashmap_isempty(m->jobs)) { |
| /* Are there any jobs now? Then make sure we have the |
| * idle pipe around. We don't really care too much |
| * whether this works or not, as the idle pipe is a |
| * feature for cosmetics, not actually useful for |
| * anything beyond that. */ |
| |
| if (m->idle_pipe[0] < 0 && m->idle_pipe[1] < 0 && |
| m->idle_pipe[2] < 0 && m->idle_pipe[3] < 0) { |
| (void) pipe2(m->idle_pipe, O_NONBLOCK|O_CLOEXEC); |
| (void) pipe2(m->idle_pipe + 2, O_NONBLOCK|O_CLOEXEC); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static Job* transaction_add_one_job(Transaction *tr, JobType type, Unit *unit, bool *is_new) { |
| Job *j, *f; |
| |
| assert(tr); |
| assert(unit); |
| |
| /* Looks for an existing prospective job and returns that. If |
| * it doesn't exist it is created and added to the prospective |
| * jobs list. */ |
| |
| f = hashmap_get(tr->jobs, unit); |
| |
| LIST_FOREACH(transaction, j, f) { |
| assert(j->unit == unit); |
| |
| if (j->type == type) { |
| if (is_new) |
| *is_new = false; |
| return j; |
| } |
| } |
| |
| j = job_new(unit, type); |
| if (!j) |
| return NULL; |
| |
| j->generation = 0; |
| j->marker = NULL; |
| j->matters_to_anchor = false; |
| j->irreversible = tr->irreversible; |
| |
| LIST_PREPEND(transaction, f, j); |
| |
| if (hashmap_replace(tr->jobs, unit, f) < 0) { |
| LIST_REMOVE(transaction, f, j); |
| job_free(j); |
| return NULL; |
| } |
| |
| if (is_new) |
| *is_new = true; |
| |
| log_trace("Added job %s/%s to transaction.", unit->id, job_type_to_string(type)); |
| |
| return j; |
| } |
| |
| static void transaction_unlink_job(Transaction *tr, Job *j, bool delete_dependencies) { |
| assert(tr); |
| assert(j); |
| |
| if (j->transaction_prev) |
| j->transaction_prev->transaction_next = j->transaction_next; |
| else if (j->transaction_next) |
| hashmap_replace(tr->jobs, j->unit, j->transaction_next); |
| else |
| hashmap_remove_value(tr->jobs, j->unit, j); |
| |
| if (j->transaction_next) |
| j->transaction_next->transaction_prev = j->transaction_prev; |
| |
| j->transaction_prev = j->transaction_next = NULL; |
| |
| while (j->subject_list) |
| job_dependency_free(j->subject_list); |
| |
| while (j->object_list) { |
| Job *other = j->object_list->matters ? j->object_list->subject : NULL; |
| |
| job_dependency_free(j->object_list); |
| |
| if (other && delete_dependencies) { |
| log_unit_debug(other->unit, |
| "Deleting job %s/%s as dependency of job %s/%s", |
| other->unit->id, job_type_to_string(other->type), |
| j->unit->id, job_type_to_string(j->type)); |
| transaction_delete_job(tr, other, delete_dependencies); |
| } |
| } |
| } |
| |
| void transaction_add_propagate_reload_jobs(Transaction *tr, Unit *unit, Job *by, bool ignore_order, sd_bus_error *e) { |
| JobType nt; |
| Unit *dep; |
| int r; |
| |
| assert(tr); |
| assert(unit); |
| |
| UNIT_FOREACH_DEPENDENCY(dep, unit, UNIT_ATOM_PROPAGATES_RELOAD_TO) { |
| nt = job_type_collapse(JOB_TRY_RELOAD, dep); |
| if (nt == JOB_NOP) |
| continue; |
| |
| r = transaction_add_job_and_dependencies(tr, nt, dep, by, false, false, false, ignore_order, e); |
| if (r < 0) { |
| log_unit_warning(dep, |
| "Cannot add dependency reload job, ignoring: %s", |
| bus_error_message(e, r)); |
| sd_bus_error_free(e); |
| } |
| } |
| } |
| |
| int transaction_add_job_and_dependencies( |
| Transaction *tr, |
| JobType type, |
| Unit *unit, |
| Job *by, |
| bool matters, |
| bool conflicts, |
| bool ignore_requirements, |
| bool ignore_order, |
| sd_bus_error *e) { |
| |
| bool is_new; |
| Unit *dep; |
| Job *ret; |
| int r; |
| |
| assert(tr); |
| assert(type < _JOB_TYPE_MAX); |
| assert(type < _JOB_TYPE_MAX_IN_TRANSACTION); |
| assert(unit); |
| |
| /* Before adding jobs for this unit, let's ensure that its state has been loaded |
| * This matters when jobs are spawned as part of coldplugging itself (see e. g. path_coldplug()). |
| * This way, we "recursively" coldplug units, ensuring that we do not look at state of |
| * not-yet-coldplugged units. */ |
| if (MANAGER_IS_RELOADING(unit->manager)) |
| unit_coldplug(unit); |
| |
| if (by) |
| log_trace("Pulling in %s/%s from %s/%s", unit->id, job_type_to_string(type), by->unit->id, job_type_to_string(by->type)); |
| |
| /* Safety check that the unit is a valid state, i.e. not in UNIT_STUB or UNIT_MERGED which should only be set |
| * temporarily. */ |
| if (!UNIT_IS_LOAD_COMPLETE(unit->load_state)) |
| return sd_bus_error_setf(e, BUS_ERROR_LOAD_FAILED, "Unit %s is not loaded properly.", unit->id); |
| |
| if (type != JOB_STOP) { |
| r = bus_unit_validate_load_state(unit, e); |
| /* The time-based cache allows to start new units without daemon-reload, |
| * but if they are already referenced (because of dependencies or ordering) |
| * then we have to force a load of the fragment. As an optimization, check |
| * first if anything in the usual paths was modified since the last time |
| * the cache was loaded. Also check if the last time an attempt to load the |
| * unit was made was before the most recent cache refresh, so that we know |
| * we need to try again — even if the cache is current, it might have been |
| * updated in a different context before we had a chance to retry loading |
| * this particular unit. |
| * |
| * Given building up the transaction is a synchronous operation, attempt |
| * to load the unit immediately. */ |
| if (r < 0 && manager_unit_cache_should_retry_load(unit)) { |
| sd_bus_error_free(e); |
| unit->load_state = UNIT_STUB; |
| r = unit_load(unit); |
| if (r < 0 || unit->load_state == UNIT_STUB) |
| unit->load_state = UNIT_NOT_FOUND; |
| r = bus_unit_validate_load_state(unit, e); |
| } |
| if (r < 0) |
| return r; |
| } |
| |
| if (!unit_job_is_applicable(unit, type)) |
| return sd_bus_error_setf(e, BUS_ERROR_JOB_TYPE_NOT_APPLICABLE, |
| "Job type %s is not applicable for unit %s.", |
| job_type_to_string(type), unit->id); |
| |
| /* First add the job. */ |
| ret = transaction_add_one_job(tr, type, unit, &is_new); |
| if (!ret) |
| return -ENOMEM; |
| |
| ret->ignore_order = ret->ignore_order || ignore_order; |
| |
| /* Then, add a link to the job. */ |
| if (by) { |
| if (!job_dependency_new(by, ret, matters, conflicts)) |
| return -ENOMEM; |
| } else { |
| /* If the job has no parent job, it is the anchor job. */ |
| assert(!tr->anchor_job); |
| tr->anchor_job = ret; |
| } |
| |
| if (is_new && !ignore_requirements && type != JOB_NOP) { |
| Set *following; |
| |
| /* If we are following some other unit, make sure we |
| * add all dependencies of everybody following. */ |
| if (unit_following_set(ret->unit, &following) > 0) { |
| SET_FOREACH(dep, following) { |
| r = transaction_add_job_and_dependencies(tr, type, dep, ret, false, false, false, ignore_order, e); |
| if (r < 0) { |
| log_unit_full_errno(dep, r == -ERFKILL ? LOG_INFO : LOG_WARNING, r, |
| "Cannot add dependency job, ignoring: %s", |
| bus_error_message(e, r)); |
| sd_bus_error_free(e); |
| } |
| } |
| |
| set_free(following); |
| } |
| |
| /* Finally, recursively add in all dependencies. */ |
| if (IN_SET(type, JOB_START, JOB_RESTART)) { |
| UNIT_FOREACH_DEPENDENCY(dep, ret->unit, UNIT_ATOM_PULL_IN_START) { |
| r = transaction_add_job_and_dependencies(tr, JOB_START, dep, ret, true, false, false, ignore_order, e); |
| if (r < 0) { |
| if (r != -EBADR) /* job type not applicable */ |
| goto fail; |
| |
| sd_bus_error_free(e); |
| } |
| } |
| |
| UNIT_FOREACH_DEPENDENCY(dep, ret->unit, UNIT_ATOM_PULL_IN_START_IGNORED) { |
| r = transaction_add_job_and_dependencies(tr, JOB_START, dep, ret, false, false, false, ignore_order, e); |
| if (r < 0) { |
| /* unit masked, job type not applicable and unit not found are not considered as errors. */ |
| log_unit_full_errno(dep, |
| IN_SET(r, -ERFKILL, -EBADR, -ENOENT) ? LOG_DEBUG : LOG_WARNING, |
| r, "Cannot add dependency job, ignoring: %s", |
| bus_error_message(e, r)); |
| sd_bus_error_free(e); |
| } |
| } |
| |
| UNIT_FOREACH_DEPENDENCY(dep, ret->unit, UNIT_ATOM_PULL_IN_VERIFY) { |
| r = transaction_add_job_and_dependencies(tr, JOB_VERIFY_ACTIVE, dep, ret, true, false, false, ignore_order, e); |
| if (r < 0) { |
| if (r != -EBADR) /* job type not applicable */ |
| goto fail; |
| |
| sd_bus_error_free(e); |
| } |
| } |
| |
| UNIT_FOREACH_DEPENDENCY(dep, ret->unit, UNIT_ATOM_PULL_IN_STOP) { |
| r = transaction_add_job_and_dependencies(tr, JOB_STOP, dep, ret, true, true, false, ignore_order, e); |
| if (r < 0) { |
| if (r != -EBADR) /* job type not applicable */ |
| goto fail; |
| |
| sd_bus_error_free(e); |
| } |
| } |
| |
| UNIT_FOREACH_DEPENDENCY(dep, ret->unit, UNIT_ATOM_PULL_IN_STOP_IGNORED) { |
| r = transaction_add_job_and_dependencies(tr, JOB_STOP, dep, ret, false, false, false, ignore_order, e); |
| if (r < 0) { |
| log_unit_warning(dep, |
| "Cannot add dependency job, ignoring: %s", |
| bus_error_message(e, r)); |
| sd_bus_error_free(e); |
| } |
| } |
| } |
| |
| if (IN_SET(type, JOB_STOP, JOB_RESTART)) { |
| UnitDependencyAtom atom; |
| JobType ptype; |
| |
| /* We propagate STOP as STOP, but RESTART only as TRY_RESTART, in order not to start |
| * dependencies that are not around. */ |
| if (type == JOB_RESTART) { |
| atom = UNIT_ATOM_PROPAGATE_RESTART; |
| ptype = JOB_TRY_RESTART; |
| } else { |
| ptype = JOB_STOP; |
| atom = UNIT_ATOM_PROPAGATE_STOP; |
| } |
| |
| UNIT_FOREACH_DEPENDENCY(dep, ret->unit, atom) { |
| JobType nt; |
| |
| nt = job_type_collapse(ptype, dep); |
| if (nt == JOB_NOP) |
| continue; |
| |
| r = transaction_add_job_and_dependencies(tr, nt, dep, ret, true, false, false, ignore_order, e); |
| if (r < 0) { |
| if (r != -EBADR) /* job type not applicable */ |
| goto fail; |
| |
| sd_bus_error_free(e); |
| } |
| } |
| } |
| |
| if (type == JOB_RELOAD) |
| transaction_add_propagate_reload_jobs(tr, ret->unit, ret, ignore_order, e); |
| |
| /* JOB_VERIFY_ACTIVE requires no dependency handling */ |
| } |
| |
| return 0; |
| |
| fail: |
| return r; |
| } |
| |
| int transaction_add_isolate_jobs(Transaction *tr, Manager *m) { |
| Unit *u; |
| char *k; |
| int r; |
| |
| assert(tr); |
| assert(m); |
| |
| HASHMAP_FOREACH_KEY(u, k, m->units) { |
| |
| /* ignore aliases */ |
| if (u->id != k) |
| continue; |
| |
| if (u->ignore_on_isolate) |
| continue; |
| |
| /* No need to stop inactive jobs */ |
| if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(u)) && !u->job) |
| continue; |
| |
| /* Is there already something listed for this? */ |
| if (hashmap_get(tr->jobs, u)) |
| continue; |
| |
| r = transaction_add_job_and_dependencies(tr, JOB_STOP, u, tr->anchor_job, true, false, false, false, NULL); |
| if (r < 0) |
| log_unit_warning_errno(u, r, "Cannot add isolate job, ignoring: %m"); |
| } |
| |
| return 0; |
| } |
| |
| int transaction_add_triggering_jobs(Transaction *tr, Unit *u) { |
| Unit *trigger; |
| int r; |
| |
| assert(tr); |
| assert(u); |
| |
| UNIT_FOREACH_DEPENDENCY(trigger, u, UNIT_ATOM_TRIGGERED_BY) { |
| |
| /* No need to stop inactive jobs */ |
| if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(trigger)) && !trigger->job) |
| continue; |
| |
| /* Is there already something listed for this? */ |
| if (hashmap_get(tr->jobs, trigger)) |
| continue; |
| |
| r = transaction_add_job_and_dependencies(tr, JOB_STOP, trigger, tr->anchor_job, true, false, false, false, NULL); |
| if (r < 0) |
| log_unit_warning_errno(u, r, "Cannot add triggered by job, ignoring: %m"); |
| } |
| |
| return 0; |
| } |
| |
| Transaction *transaction_new(bool irreversible) { |
| Transaction *tr; |
| |
| tr = new0(Transaction, 1); |
| if (!tr) |
| return NULL; |
| |
| tr->jobs = hashmap_new(NULL); |
| if (!tr->jobs) |
| return mfree(tr); |
| |
| tr->irreversible = irreversible; |
| |
| return tr; |
| } |
| |
| void transaction_free(Transaction *tr) { |
| assert(hashmap_isempty(tr->jobs)); |
| hashmap_free(tr->jobs); |
| free(tr); |
| } |
