active-idle
like active, but no writes have been seen for a while (safe_mode_delay).
+ bitmap/location
+ This indicates where the write-intent bitmap for the array is
+ stored.
+ It can be one of "none", "file" or "[+-]N".
+ "file" may later be extended to "file:/file/name"
+ "[+-]N" means that many sectors from the start of the metadata.
+ This is replicated on all devices. For arrays with externally
+ managed metadata, the offset is from the beginning of the
+ device.
+ bitmap/chunksize
+ The size, in bytes, of the chunk which will be represented by a
+ single bit. For RAID456, it is a portion of an individual
+ device. For RAID10, it is a portion of the array. For RAID1, it
+ is both (they come to the same thing).
+ bitmap/time_base
+ The time, in seconds, between looking for bits in the bitmap to
+ be cleared. In the current implementation, a bit will be cleared
+ between 2 and 3 times "time_base" after all the covered blocks
+ are known to be in-sync.
+ bitmap/backlog
+ When write-mostly devices are active in a RAID1, write requests
+ to those devices proceed in the background - the filesystem (or
+ other user of the device) does not have to wait for them.
+ 'backlog' sets a limit on the number of concurrent background
+ writes. If there are more than this, new writes will by
+ synchronous.
+
+
+
As component devices are added to an md array, they appear in the 'md'
directory as new directories named
bitmap->events_cleared = bitmap->mddev->events;
sb->events_cleared = cpu_to_le64(bitmap->events_cleared);
}
+ /* Just in case these have been changed via sysfs: */
+ sb->daemon_sleep = cpu_to_le32(bitmap->mddev->bitmap_info.daemon_sleep/HZ);
+ sb->write_behind = cpu_to_le32(bitmap->mddev->bitmap_info.max_write_behind);
kunmap_atomic(sb, KM_USER0);
write_page(bitmap, bitmap->sb_page, 1);
}
return err;
}
+static ssize_t
+location_show(mddev_t *mddev, char *page)
+{
+ ssize_t len;
+ if (mddev->bitmap_info.file) {
+ len = sprintf(page, "file");
+ } else if (mddev->bitmap_info.offset) {
+ len = sprintf(page, "%+lld", (long long)mddev->bitmap_info.offset);
+ } else
+ len = sprintf(page, "none");
+ len += sprintf(page+len, "\n");
+ return len;
+}
+
+static ssize_t
+location_store(mddev_t *mddev, const char *buf, size_t len)
+{
+
+ if (mddev->pers) {
+ if (!mddev->pers->quiesce)
+ return -EBUSY;
+ if (mddev->recovery || mddev->sync_thread)
+ return -EBUSY;
+ }
+
+ if (mddev->bitmap || mddev->bitmap_info.file ||
+ mddev->bitmap_info.offset) {
+ /* bitmap already configured. Only option is to clear it */
+ if (strncmp(buf, "none", 4) != 0)
+ return -EBUSY;
+ if (mddev->pers) {
+ mddev->pers->quiesce(mddev, 1);
+ bitmap_destroy(mddev);
+ mddev->pers->quiesce(mddev, 0);
+ }
+ mddev->bitmap_info.offset = 0;
+ if (mddev->bitmap_info.file) {
+ struct file *f = mddev->bitmap_info.file;
+ mddev->bitmap_info.file = NULL;
+ restore_bitmap_write_access(f);
+ fput(f);
+ }
+ } else {
+ /* No bitmap, OK to set a location */
+ long long offset;
+ if (strncmp(buf, "none", 4) == 0)
+ /* nothing to be done */;
+ else if (strncmp(buf, "file:", 5) == 0) {
+ /* Not supported yet */
+ return -EINVAL;
+ } else {
+ int rv;
+ if (buf[0] == '+')
+ rv = strict_strtoll(buf+1, 10, &offset);
+ else
+ rv = strict_strtoll(buf, 10, &offset);
+ if (rv)
+ return rv;
+ if (offset == 0)
+ return -EINVAL;
+ if (mddev->major_version == 0 &&
+ offset != mddev->bitmap_info.default_offset)
+ return -EINVAL;
+ mddev->bitmap_info.offset = offset;
+ if (mddev->pers) {
+ mddev->pers->quiesce(mddev, 1);
+ rv = bitmap_create(mddev);
+ if (rv) {
+ bitmap_destroy(mddev);
+ mddev->bitmap_info.offset = 0;
+ }
+ mddev->pers->quiesce(mddev, 0);
+ if (rv)
+ return rv;
+ }
+ }
+ }
+ if (!mddev->external) {
+ /* Ensure new bitmap info is stored in
+ * metadata promptly.
+ */
+ set_bit(MD_CHANGE_DEVS, &mddev->flags);
+ md_wakeup_thread(mddev->thread);
+ }
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_location =
+__ATTR(location, S_IRUGO|S_IWUSR, location_show, location_store);
+
+static ssize_t
+timeout_show(mddev_t *mddev, char *page)
+{
+ ssize_t len;
+ unsigned long secs = mddev->bitmap_info.daemon_sleep / HZ;
+ unsigned long jifs = mddev->bitmap_info.daemon_sleep % HZ;
+
+ len = sprintf(page, "%lu", secs);
+ if (jifs)
+ len += sprintf(page+len, ".%03u", jiffies_to_msecs(jifs));
+ len += sprintf(page+len, "\n");
+ return len;
+}
+
+static ssize_t
+timeout_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ /* timeout can be set at any time */
+ unsigned long timeout;
+ int rv = strict_strtoul_scaled(buf, &timeout, 4);
+ if (rv)
+ return rv;
+
+ /* just to make sure we don't overflow... */
+ if (timeout >= LONG_MAX / HZ)
+ return -EINVAL;
+
+ timeout = timeout * HZ / 10000;
+
+ if (timeout >= MAX_SCHEDULE_TIMEOUT)
+ timeout = MAX_SCHEDULE_TIMEOUT-1;
+ if (timeout < 1)
+ timeout = 1;
+ mddev->bitmap_info.daemon_sleep = timeout;
+ if (mddev->thread) {
+ /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then
+ * the bitmap is all clean and we don't need to
+ * adjust the timeout right now
+ */
+ if (mddev->thread->timeout < MAX_SCHEDULE_TIMEOUT) {
+ mddev->thread->timeout = timeout;
+ md_wakeup_thread(mddev->thread);
+ }
+ }
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_timeout =
+__ATTR(time_base, S_IRUGO|S_IWUSR, timeout_show, timeout_store);
+
+static ssize_t
+backlog_show(mddev_t *mddev, char *page)
+{
+ return sprintf(page, "%lu\n", mddev->bitmap_info.max_write_behind);
+}
+
+static ssize_t
+backlog_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ unsigned long backlog;
+ int rv = strict_strtoul(buf, 10, &backlog);
+ if (rv)
+ return rv;
+ if (backlog > COUNTER_MAX)
+ return -EINVAL;
+ mddev->bitmap_info.max_write_behind = backlog;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_backlog =
+__ATTR(backlog, S_IRUGO|S_IWUSR, backlog_show, backlog_store);
+
+static ssize_t
+chunksize_show(mddev_t *mddev, char *page)
+{
+ return sprintf(page, "%lu\n", mddev->bitmap_info.chunksize);
+}
+
+static ssize_t
+chunksize_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ /* Can only be changed when no bitmap is active */
+ int rv;
+ unsigned long csize;
+ if (mddev->bitmap)
+ return -EBUSY;
+ rv = strict_strtoul(buf, 10, &csize);
+ if (rv)
+ return rv;
+ if (csize < 512 ||
+ !is_power_of_2(csize))
+ return -EINVAL;
+ mddev->bitmap_info.chunksize = csize;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_chunksize =
+__ATTR(chunksize, S_IRUGO|S_IWUSR, chunksize_show, chunksize_store);
+
+static struct attribute *md_bitmap_attrs[] = {
+ &bitmap_location.attr,
+ &bitmap_timeout.attr,
+ &bitmap_backlog.attr,
+ &bitmap_chunksize.attr,
+ NULL
+};
+struct attribute_group md_bitmap_group = {
+ .name = "bitmap",
+ .attrs = md_bitmap_attrs,
+};
+
+
/* the bitmap API -- for raid personalities */
EXPORT_SYMBOL(bitmap_startwrite);
EXPORT_SYMBOL(bitmap_endwrite);
projects / kernel.git / commitdiff