From: Yu Kuai <yukuai3@xxxxxxxxxx>
Include following APIs:
- llbitmap_create
- llbitmap_resize
- llbitmap_load
- llbitmap_destroy
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
drivers/md/md-llbitmap.c | 322 +++++++++++++++++++++++++++++++++++++++
1 file changed, 322 insertions(+)
diff --git a/drivers/md/md-llbitmap.c b/drivers/md/md-llbitmap.c
index 4d5f9a139a25..23283c4f7263 100644
--- a/drivers/md/md-llbitmap.c
+++ b/drivers/md/md-llbitmap.c
@@ -689,4 +689,326 @@ static void llbitmap_resume(struct llbitmap *llbitmap, int page_idx)
wake_up(&pctl->wait);
}
+static int llbitmap_check_support(struct mddev *mddev)
+{
+ if (test_bit(MD_HAS_JOURNAL, &mddev->flags)) {
+ pr_notice("md/llbitmap: %s: array with journal cannot have bitmap\n",
+ mdname(mddev));
+ return -EBUSY;
+ }
+
+ if (mddev->bitmap_info.space == 0) {
+ if (mddev->bitmap_info.default_space == 0) {
+ pr_notice("md/llbitmap: %s: no space for bitmap\n",
+ mdname(mddev));
+ return -ENOSPC;
+ }
+ }
+
+ if (!mddev->persistent) {
+ pr_notice("md/llbitmap: %s: array must be persistent\n",
+ mdname(mddev));
+ return -EOPNOTSUPP;
+ }
+
+ if (mddev->bitmap_info.file) {
+ pr_notice("md/llbitmap: %s: doesn't support bitmap file\n",
+ mdname(mddev));
+ return -EOPNOTSUPP;
+ }
+
+ if (mddev->bitmap_info.external) {
+ pr_notice("md/llbitmap: %s: doesn't support external metadata\n",
+ mdname(mddev));
+ return -EOPNOTSUPP;
+ }
+
+ if (mddev_is_dm(mddev)) {
+ pr_notice("md/llbitmap: %s: doesn't support dm-raid\n",
+ mdname(mddev));
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static int llbitmap_init(struct llbitmap *llbitmap)
+{
+ struct mddev *mddev = llbitmap->mddev;
+ sector_t blocks = mddev->resync_max_sectors;
+ unsigned long chunksize = MIN_CHUNK_SIZE;
+ unsigned long chunks = DIV_ROUND_UP(blocks, chunksize);
+ unsigned long space = mddev->bitmap_info.space << SECTOR_SHIFT;
+ int ret;
+
+ while (chunks > space) {
+ chunksize = chunksize << 1;
+ chunks = DIV_ROUND_UP(blocks, chunksize);
+ }
+
+ llbitmap->chunkshift = ffz(~chunksize);
+ llbitmap->chunksize = chunksize;
+ llbitmap->chunks = chunks;
+ mddev->bitmap_info.daemon_sleep = DEFAULT_DAEMON_SLEEP;
+
+ ret = llbitmap_cache_pages(llbitmap);
+ if (ret)
+ return ret;
+
+ llbitmap_state_machine(llbitmap, 0, llbitmap->chunks - 1, BitmapActionInit);
+ return 0;
+}
+
+static int llbitmap_read_sb(struct llbitmap *llbitmap)
+{
+ struct mddev *mddev = llbitmap->mddev;
+ unsigned long daemon_sleep;
+ unsigned long chunksize;
+ unsigned long events;
+ struct page *sb_page;
+ bitmap_super_t *sb;
+ int ret = -EINVAL;
+
+ if (!mddev->bitmap_info.offset) {
+ pr_err("md/llbitmap: %s: no super block found", mdname(mddev));
+ return -EINVAL;
+ }
+
+ sb_page = llbitmap_read_page(llbitmap, 0);
+ if (IS_ERR(sb_page)) {
+ pr_err("md/llbitmap: %s: read super block failed",
+ mdname(mddev));
+ ret = -EIO;
+ goto out;
+ }
+
+ sb = kmap_local_page(sb_page);
+ if (sb->magic != cpu_to_le32(BITMAP_MAGIC)) {
+ pr_err("md/llbitmap: %s: invalid super block magic number",
+ mdname(mddev));
+ goto out_put_page;
+ }
+
+ if (sb->version != cpu_to_le32(BITMAP_MAJOR_LOCKLESS)) {
+ pr_err("md/llbitmap: %s: invalid super block version",
+ mdname(mddev));
+ goto out_put_page;
+ }
+
+ if (memcmp(sb->uuid, mddev->uuid, 16)) {
+ pr_err("md/llbitmap: %s: bitmap superblock UUID mismatch\n",
+ mdname(mddev));
+ goto out_put_page;
+ }
+
+ if (mddev->bitmap_info.space == 0) {
+ int room = le32_to_cpu(sb->sectors_reserved);
+
+ if (room)
+ mddev->bitmap_info.space = room;
+ else
+ mddev->bitmap_info.space = mddev->bitmap_info.default_space;
+ }
+ llbitmap->flags = le32_to_cpu(sb->state);
+ if (test_and_clear_bit(BITMAP_FIRST_USE, &llbitmap->flags)) {
+ ret = llbitmap_init(llbitmap);
+ goto out_put_page;
+ }
+
+ chunksize = le32_to_cpu(sb->chunksize);
+ if (!is_power_of_2(chunksize)) {
+ pr_err("md/llbitmap: %s: chunksize not a power of 2",
+ mdname(mddev));
+ goto out_put_page;
+ }
+
+ if (chunksize < DIV_ROUND_UP(mddev->resync_max_sectors,
+ mddev->bitmap_info.space << SECTOR_SHIFT)) {
+ pr_err("md/llbitmap: %s: chunksize too small %lu < %llu / %lu",
+ mdname(mddev), chunksize, mddev->resync_max_sectors,
+ mddev->bitmap_info.space);
+ goto out_put_page;
+ }
+
+ daemon_sleep = le32_to_cpu(sb->daemon_sleep);
+ if (daemon_sleep < 1 || daemon_sleep > MAX_SCHEDULE_TIMEOUT / HZ) {
+ pr_err("md/llbitmap: %s: daemon sleep %lu period out of range",
+ mdname(mddev), daemon_sleep);
+ goto out_put_page;
+ }
+
+ events = le64_to_cpu(sb->events);
+ if (events < mddev->events) {
+ pr_warn("md/llbitmap :%s: bitmap file is out of date (%lu < %llu) -- forcing full recovery",
+ mdname(mddev), events, mddev->events);
+ set_bit(BITMAP_STALE, &llbitmap->flags);
+ }
+
+ sb->sync_size = cpu_to_le64(mddev->resync_max_sectors);
+ mddev->bitmap_info.chunksize = chunksize;
+ mddev->bitmap_info.daemon_sleep = daemon_sleep;
+
+ llbitmap->chunksize = chunksize;
+ llbitmap->chunks = DIV_ROUND_UP(mddev->resync_max_sectors, chunksize);
+ llbitmap->chunkshift = ffz(~chunksize);
+ ret = llbitmap_cache_pages(llbitmap);
+
+out_put_page:
+ __free_page(sb_page);
+out:
+ kunmap_local(sb);
+ return ret;
+}
+
+static void llbitmap_pending_timer_fn(struct timer_list *t)
+{
+ struct llbitmap *llbitmap = from_timer(llbitmap, t, pending_timer);
+
+ if (work_busy(&llbitmap->daemon_work)) {
+ pr_warn("daemon_work not finished\n");
+ set_bit(BITMAP_DAEMON_BUSY, &llbitmap->flags);
+ return;
+ }
+
+ queue_work(md_llbitmap_io_wq, &llbitmap->daemon_work);
+}
+
+static void md_llbitmap_daemon_fn(struct work_struct *work)
+{
+ struct llbitmap *llbitmap =
+ container_of(work, struct llbitmap, daemon_work);
+ unsigned long start;
+ unsigned long end;
+ bool restart;
+ int idx;
+
+ if (llbitmap->mddev->degraded)
+ return;
+
+retry:
+ start = 0;
+ end = min(llbitmap->chunks, PAGE_SIZE - BITMAP_SB_SIZE) - 1;
+ restart = false;
+
+ for (idx = 0; idx < llbitmap->nr_pages; idx++) {
+ struct llbitmap_page_ctl *pctl = llbitmap->pctl[idx];
+
+ if (idx > 0) {
+ start = end + 1;
+ end = min(end + PAGE_SIZE, llbitmap->chunks - 1);
+ }
+
+ if (!test_bit(LLPageFlush, &pctl->flags) &&
+ time_before(jiffies, pctl->expire)) {
+ restart = true;
+ continue;
+ }
+
+ llbitmap_suspend(llbitmap, idx);
+ llbitmap_state_machine(llbitmap, start, end, BitmapActionDaemon);
+ llbitmap_resume(llbitmap, idx);
+ }
+
+ /*
+ * If the daemon took a long time to finish, retry to prevent missing
+ * clearing dirty bits.
+ */
+ if (test_and_clear_bit(BITMAP_DAEMON_BUSY, &llbitmap->flags))
+ goto retry;
+
+ /* If some page is dirty but not expired, setup timer again */
+ if (restart)
+ mod_timer(&llbitmap->pending_timer,
+ jiffies + llbitmap->mddev->bitmap_info.daemon_sleep * HZ);
+}
+
+static int llbitmap_create(struct mddev *mddev)
+{
+ struct llbitmap *llbitmap;
+ int ret;
+
+ ret = llbitmap_check_support(mddev);
+ if (ret)
+ return ret;
+
+ llbitmap = kzalloc(sizeof(*llbitmap), GFP_KERNEL);
+ if (!llbitmap)
+ return -ENOMEM;
+
+ llbitmap->mddev = mddev;
+ llbitmap->io_size = bdev_logical_block_size(mddev->gendisk->part0);
+ llbitmap->bits_per_page = PAGE_SIZE / llbitmap->io_size;
+
+ timer_setup(&llbitmap->pending_timer, llbitmap_pending_timer_fn, 0);
+ INIT_WORK(&llbitmap->daemon_work, md_llbitmap_daemon_fn);
+ atomic_set(&llbitmap->behind_writes, 0);
+ init_waitqueue_head(&llbitmap->behind_wait);
+
+ mutex_lock(&mddev->bitmap_info.mutex);
+ mddev->bitmap = llbitmap;
+ ret = llbitmap_read_sb(llbitmap);
+ mutex_unlock(&mddev->bitmap_info.mutex);
+ if (ret)
+ goto err_out;
+
+ return 0;
+
+err_out:
+ kfree(llbitmap);
+ return ret;
+}
+
+static int llbitmap_resize(struct mddev *mddev, sector_t blocks, int chunksize)
+{
+ struct llbitmap *llbitmap = mddev->bitmap;
+ unsigned long chunks;
+
+ if (chunksize == 0)
+ chunksize = llbitmap->chunksize;
+
+ /* If there is enough space, leave the chunksize unchanged. */
+ chunks = DIV_ROUND_UP(blocks, chunksize);
+ while (chunks > mddev->bitmap_info.space << SECTOR_SHIFT) {
+ chunksize = chunksize << 1;
+ chunks = DIV_ROUND_UP(blocks, chunksize);
+ }
+
+ llbitmap->chunkshift = ffz(~chunksize);
+ llbitmap->chunksize = chunksize;
+ llbitmap->chunks = chunks;
+
+ return 0;
+}
+
+static int llbitmap_load(struct mddev *mddev)
+{
+ enum llbitmap_action action = BitmapActionReload;
+ struct llbitmap *llbitmap = mddev->bitmap;
+
+ if (test_and_clear_bit(BITMAP_STALE, &llbitmap->flags))
+ action = BitmapActionStale;
+
+ llbitmap_state_machine(llbitmap, 0, llbitmap->chunks - 1, action);
+ return 0;
+}
+
+static void llbitmap_destroy(struct mddev *mddev)
+{
+ struct llbitmap *llbitmap = mddev->bitmap;
+
+ if (!llbitmap)
+ return;
+
+ mutex_lock(&mddev->bitmap_info.mutex);
+
+ timer_delete_sync(&llbitmap->pending_timer);
+ flush_workqueue(md_llbitmap_io_wq);
+ flush_workqueue(md_llbitmap_unplug_wq);
+
+ mddev->bitmap = NULL;
+ llbitmap_free_pages(llbitmap);
+ kfree(llbitmap);
+ mutex_unlock(&mddev->bitmap_info.mutex);
+}
+
#endif /* CONFIG_MD_LLBITMAP */
--
2.39.2
