1 /*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <sys/types.h>
18 #include <sys/stat.h>
19 #include <fcntl.h>
20 #include <unistd.h>
21 #include <sys/ioctl.h>
22 #include <string.h>
23 #include <limits.h>
24 #include <linux/fs.h>
25 #include <time.h>
26 #include <fs_mgr.h>
27 #include <pthread.h>
28 #define LOG_TAG "fstrim"
29 #include "cutils/log.h"
30 #include "hardware_legacy/power.h"
31
32 /* These numbers must match what the MountService specified in
33 * frameworks/base/services/java/com/android/server/EventLogTags.logtags
34 */
35 #define LOG_FSTRIM_START 2755
36 #define LOG_FSTRIM_FINISH 2756
37
38 #define FSTRIM_WAKELOCK "dofstrim"
39
40 #define UNUSED __attribute__((unused))
41
42 /* From a would-be kernel header */
43 #define FIDTRIM _IOWR('f', 128, struct fstrim_range) /* Deep discard trim */
44
get_boot_time_ms(void)45 static unsigned long long get_boot_time_ms(void)
46 {
47 struct timespec t;
48 unsigned long long time_ms;
49
50 t.tv_sec = 0;
51 t.tv_nsec = 0;
52 clock_gettime(CLOCK_BOOTTIME, &t);
53 time_ms = (t.tv_sec * 1000LL) + (t.tv_nsec / 1000000);
54
55 return time_ms;
56 }
57
do_fstrim_filesystems(void * thread_arg)58 static void *do_fstrim_filesystems(void *thread_arg)
59 {
60 int i;
61 int fd;
62 int ret = 0;
63 struct fstrim_range range = { 0 };
64 struct stat sb;
65 extern struct fstab *fstab;
66 int deep_trim = !!thread_arg;
67
68 SLOGI("Starting fstrim work...\n");
69
70 /* Log the start time in the event log */
71 LOG_EVENT_LONG(LOG_FSTRIM_START, get_boot_time_ms());
72
73 for (i = 0; i < fstab->num_entries; i++) {
74 /* Skip raw partitions */
75 if (!strcmp(fstab->recs[i].fs_type, "emmc") ||
76 !strcmp(fstab->recs[i].fs_type, "mtd")) {
77 continue;
78 }
79 /* Skip read-only filesystems */
80 if (fstab->recs[i].flags & MS_RDONLY) {
81 continue;
82 }
83 if (fs_mgr_is_voldmanaged(&fstab->recs[i])) {
84 continue; /* Should we trim fat32 filesystems? */
85 }
86
87 if (stat(fstab->recs[i].mount_point, &sb) == -1) {
88 SLOGE("Cannot stat mount point %s\n", fstab->recs[i].mount_point);
89 ret = -1;
90 continue;
91 }
92 if (!S_ISDIR(sb.st_mode)) {
93 SLOGE("%s is not a directory\n", fstab->recs[i].mount_point);
94 ret = -1;
95 continue;
96 }
97
98 fd = open(fstab->recs[i].mount_point, O_RDONLY);
99 if (fd < 0) {
100 SLOGE("Cannot open %s for FITRIM\n", fstab->recs[i].mount_point);
101 ret = -1;
102 continue;
103 }
104
105 memset(&range, 0, sizeof(range));
106 range.len = ULLONG_MAX;
107 SLOGI("Invoking %s ioctl on %s", deep_trim ? "FIDTRIM" : "FITRIM", fstab->recs[i].mount_point);
108
109 ret = ioctl(fd, deep_trim ? FIDTRIM : FITRIM, &range);
110 if (ret) {
111 SLOGE("%s ioctl failed on %s (error %d/%s)", deep_trim ? "FIDTRIM" : "FITRIM", fstab->recs[i].mount_point, errno, strerror(errno));
112 ret = -1;
113 } else {
114 SLOGI("Trimmed %llu bytes on %s\n", range.len, fstab->recs[i].mount_point);
115 }
116 close(fd);
117 }
118
119 /* Log the finish time in the event log */
120 LOG_EVENT_LONG(LOG_FSTRIM_FINISH, get_boot_time_ms());
121
122 SLOGI("Finished fstrim work.\n");
123
124 /* Release the wakelock that let us work */
125 release_wake_lock(FSTRIM_WAKELOCK);
126
127 return (void *)(uintptr_t)ret;
128 }
129
fstrim_filesystems(int deep_trim)130 int fstrim_filesystems(int deep_trim)
131 {
132 pthread_t t;
133 int ret;
134
135 /* Get a wakelock as this may take a while, and we don't want the
136 * device to sleep on us.
137 */
138 acquire_wake_lock(PARTIAL_WAKE_LOCK, FSTRIM_WAKELOCK);
139
140 /* Depending on the emmc chip and size, this can take upwards
141 * of a few minutes. If done in the same thread as the caller
142 * of this function, that would block vold from accepting any
143 * commands until the trim is finished. So start another thread
144 * to do the work, and return immediately.
145 *
146 * This function should not be called more than once per day, but
147 * even if it is called a second time before the first one finishes,
148 * the kernel will "do the right thing" and split the work between
149 * the two ioctls invoked in separate threads.
150 */
151 ret = pthread_create(&t, NULL, do_fstrim_filesystems, (void *)(intptr_t)deep_trim);
152 if (ret) {
153 SLOGE("Cannot create thread to do fstrim");
154 return ret;
155 }
156
157 ret = pthread_detach(t);
158 if (ret) {
159 SLOGE("Cannot detach thread doing fstrim");
160 return ret;
161 }
162
163 return 0;
164 }
165