1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2015 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 #include <sys/sendfile.h>
24 #include "sd-daemon.h"
26 #include "ratelimit.h"
27 #include "btrfs-util.h"
28 #include "import-common.h"
29 #include "export-tar.h"
31 #define COPY_BUFFER_SIZE (16*1024)
36 TarExportFinished on_finished;
45 ImportCompress compress;
47 sd_event_source *output_event_source;
51 size_t buffer_allocated;
53 uint64_t written_compressed;
54 uint64_t written_uncompressed;
59 uint64_t quota_referenced;
61 unsigned last_percent;
62 RateLimit progress_rate_limit;
68 TarExport *tar_export_unref(TarExport *e) {
72 sd_event_source_unref(e->output_event_source);
75 (void) kill_and_sigcont(e->tar_pid, SIGKILL);
76 (void) wait_for_terminate(e->tar_pid, NULL);
80 (void) btrfs_subvol_remove(e->temp_path);
84 import_compress_free(&e->compress);
86 sd_event_unref(e->event);
88 safe_close(e->tar_fd);
100 TarExportFinished on_finished,
103 _cleanup_(tar_export_unrefp) TarExport *e = NULL;
108 e = new0(TarExport, 1);
112 e->output_fd = e->tar_fd = -1;
113 e->on_finished = on_finished;
114 e->userdata = userdata;
115 e->quota_referenced = (uint64_t) -1;
117 RATELIMIT_INIT(e->progress_rate_limit, 100 * USEC_PER_MSEC, 1);
118 e->last_percent = (unsigned) -1;
121 e->event = sd_event_ref(event);
123 r = sd_event_default(&e->event);
134 static void tar_export_report_progress(TarExport *e) {
138 /* Do we have any quota info? I fnot, we don't know anything about the progress */
139 if (e->quota_referenced == (uint64_t) -1)
142 if (e->written_uncompressed >= e->quota_referenced)
145 percent = (unsigned) ((e->written_uncompressed * UINT64_C(100)) / e->quota_referenced);
147 if (percent == e->last_percent)
150 if (!ratelimit_test(&e->progress_rate_limit))
153 sd_notifyf(false, "X_IMPORT_PROGRESS=%u", percent);
154 log_info("Exported %u%%.", percent);
156 e->last_percent = percent;
159 static int tar_export_process(TarExport *e) {
165 if (!e->tried_splice && e->compress.type == IMPORT_COMPRESS_UNCOMPRESSED) {
167 l = splice(e->tar_fd, NULL, e->output_fd, NULL, COPY_BUFFER_SIZE, 0);
172 e->tried_splice = true;
177 e->written_uncompressed += l;
178 e->written_compressed += l;
180 tar_export_report_progress(e);
186 while (e->buffer_size <= 0) {
187 uint8_t input[COPY_BUFFER_SIZE];
194 l = read(e->tar_fd, input, sizeof(input));
196 r = log_error_errno(errno, "Failed to read tar file: %m");
202 r = import_compress_finish(&e->compress, &e->buffer, &e->buffer_size, &e->buffer_allocated);
204 e->written_uncompressed += l;
205 r = import_compress(&e->compress, input, l, &e->buffer, &e->buffer_size, &e->buffer_allocated);
208 r = log_error_errno(r, "Failed to encode: %m");
213 l = write(e->output_fd, e->buffer, e->buffer_size);
218 r = log_error_errno(errno, "Failed to write output file: %m");
222 assert((size_t) l <= e->buffer_size);
223 memmove(e->buffer, (uint8_t*) e->buffer + l, e->buffer_size - l);
225 e->written_compressed += l;
227 tar_export_report_progress(e);
233 e->on_finished(e, r, e->userdata);
235 sd_event_exit(e->event, r);
240 static int tar_export_on_output(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
241 TarExport *i = userdata;
243 return tar_export_process(i);
246 static int tar_export_on_defer(sd_event_source *s, void *userdata) {
247 TarExport *i = userdata;
249 return tar_export_process(i);
252 int tar_export_start(TarExport *e, const char *path, int fd, ImportCompressType compress) {
253 _cleanup_close_ int sfd = -1;
259 assert(compress < _IMPORT_COMPRESS_TYPE_MAX);
260 assert(compress != IMPORT_COMPRESS_UNKNOWN);
262 if (e->output_fd >= 0)
265 sfd = open(path, O_DIRECTORY|O_RDONLY|O_NOCTTY|O_CLOEXEC);
269 if (fstat(sfd, &e->st) < 0)
272 r = fd_nonblock(fd, true);
276 r = free_and_strdup(&e->path, path);
280 e->quota_referenced = (uint64_t) -1;
282 if (e->st.st_ino == 256) { /* might be a btrfs subvolume? */
285 r = btrfs_subvol_get_quota_fd(sfd, &q);
287 e->quota_referenced = q.referenced;
292 r = tempfn_random(path, &e->temp_path);
296 /* Let's try to make a snapshot, if we can, so that the export is atomic */
297 r = btrfs_subvol_snapshot_fd(sfd, e->temp_path, true, false);
299 log_debug_errno(r, "Couldn't create snapshot %s of %s, not exporting atomically: %m", e->temp_path, path);
305 r = import_compress_init(&e->compress, compress);
309 r = sd_event_add_io(e->event, &e->output_event_source, fd, EPOLLOUT, tar_export_on_output, e);
311 r = sd_event_add_defer(e->event, &e->output_event_source, tar_export_on_defer, e);
315 r = sd_event_source_set_enabled(e->output_event_source, SD_EVENT_ON);
320 e->tar_fd = import_fork_tar_c(e->temp_path ?: e->path, &e->tar_pid);
322 e->output_event_source = sd_event_source_unref(e->output_event_source);