raid5-cache: add trim support for log (4b482044) · Commits · 戴 / test

drivers/md/raid5-cache.c

+62 −1

Original line number	Diff line number	Diff line
		@@ -85,6 +85,7 @@ struct r5l_log {
		spinlock_t no_space_stripes_lock;

		bool need_cache_flush;
		bool in_teardown;
		};

		/*
		@@ -644,6 +645,60 @@ void r5l_flush_stripe_to_raid(struct r5l_log *log)
		}

		static void r5l_write_super(struct r5l_log *log, sector_t cp);
		static void r5l_write_super_and_discard_space(struct r5l_log *log,
		sector_t end)
		{
		struct block_device *bdev = log->rdev->bdev;
		struct mddev *mddev;

		r5l_write_super(log, end);

		if (!blk_queue_discard(bdev_get_queue(bdev)))
		return;

		mddev = log->rdev->mddev;
		/*
		* This is to avoid a deadlock. r5l_quiesce holds reconfig_mutex and
		* wait for this thread to finish. This thread waits for
		* MD_CHANGE_PENDING clear, which is supposed to be done in
		* md_check_recovery(). md_check_recovery() tries to get
		* reconfig_mutex. Since r5l_quiesce already holds the mutex,
		* md_check_recovery() fails, so the PENDING never get cleared. The
		* in_teardown check workaround this issue.
		*/
		if (!log->in_teardown) {
		set_bit(MD_CHANGE_DEVS, &mddev->flags);
		set_bit(MD_CHANGE_PENDING, &mddev->flags);
		md_wakeup_thread(mddev->thread);
		wait_event(mddev->sb_wait,
		!test_bit(MD_CHANGE_PENDING, &mddev->flags) \|\|
		log->in_teardown);
		/*
		* r5l_quiesce could run after in_teardown check and hold
		* mutex first. Superblock might get updated twice.
		*/
		if (log->in_teardown)
		md_update_sb(mddev, 1);
		} else {
		WARN_ON(!mddev_is_locked(mddev));
		md_update_sb(mddev, 1);
		}

		if (log->last_checkpoint < end) {
		blkdev_issue_discard(bdev,
		log->last_checkpoint + log->rdev->data_offset,
		end - log->last_checkpoint, GFP_NOIO, 0);
		} else {
		blkdev_issue_discard(bdev,
		log->last_checkpoint + log->rdev->data_offset,
		log->device_size - log->last_checkpoint,
		GFP_NOIO, 0);
		blkdev_issue_discard(bdev, log->rdev->data_offset, end,
		GFP_NOIO, 0);
		}
		}


		static void r5l_do_reclaim(struct r5l_log *log)
		{
		sector_t reclaim_target = xchg(&log->reclaim_target, 0);
		@@ -685,7 +740,7 @@ static void r5l_do_reclaim(struct r5l_log *log)
		* here, because the log area might be reused soon and we don't want to
		* confuse recovery
		*/
		r5l_write_super(log, next_checkpoint);
		r5l_write_super_and_discard_space(log, next_checkpoint);

		mutex_lock(&log->io_mutex);
		log->last_checkpoint = next_checkpoint;
		@@ -721,9 +776,11 @@ static void r5l_wake_reclaim(struct r5l_log *log, sector_t space)

		void r5l_quiesce(struct r5l_log *log, int state)
		{
		struct mddev *mddev;
		if (!log \|\| state == 2)
		return;
		if (state == 0) {
		log->in_teardown = 0;
		log->reclaim_thread = md_register_thread(r5l_reclaim_thread,
		log->rdev->mddev, "reclaim");
		} else if (state == 1) {
		@@ -731,6 +788,10 @@ void r5l_quiesce(struct r5l_log *log, int state)
		* at this point all stripes are finished, so io_unit is at
		* least in STRIPE_END state
		*/
		log->in_teardown = 1;
		/* make sure r5l_write_super_and_discard_space exits */
		mddev = log->rdev->mddev;
		wake_up(&mddev->sb_wait);
		r5l_wake_reclaim(log, -1L);
		md_unregister_thread(&log->reclaim_thread);
		r5l_do_reclaim(log);

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