1 // SPDX-License-Identifier: GPL-2.0-only
9  * update_fastmap_work_fn - calls ubi_update_fastmap from a work queue
17 	spin_lock(&ubi->wl_lock);  in update_fastmap_work_fn()
18 	ubi->fm_work_scheduled = 0;  in update_fastmap_work_fn()
19 	spin_unlock(&ubi->wl_lock);  in update_fastmap_work_fn()
23  * find_anchor_wl_entry - find wear-leveling entry to used as anchor PEB.
24  * @root: the RB-tree where to look for
33 		if (e->pnum < UBI_FM_MAX_START && e->ec < max_ec) {  in find_anchor_wl_entry()
35 			max_ec = e->ec;  in find_anchor_wl_entry()
45 	wl_tree_add(e, &ubi->free);  in return_unused_peb()
46 	ubi->free_count++;  in return_unused_peb()
50  * return_unused_pool_pebs - returns unused PEB to the free tree.
60 	for (i = pool->used; i < pool->size; i++) {  in return_unused_pool_pebs()
61 		e = ubi->lookuptbl[pool->pebs[i]];  in return_unused_pool_pebs()
67  * ubi_wl_get_fm_peb - find a physical erase block with a given maximal number.
79 	if (!ubi->free.rb_node)  in ubi_wl_get_fm_peb()
83 		e = find_anchor_wl_entry(&ubi->free);  in ubi_wl_get_fm_peb()
85 		e = find_mean_wl_entry(ubi, &ubi->free);  in ubi_wl_get_fm_peb()
90 	self_check_in_wl_tree(ubi, e, &ubi->free);  in ubi_wl_get_fm_peb()
94 	rb_erase(&e->u.rb, &ubi->free);  in ubi_wl_get_fm_peb()
95 	ubi->free_count--;  in ubi_wl_get_fm_peb()
101  * wait_free_pebs_for_pool - wait until there enough free pebs
110 	struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool;  in wait_free_pebs_for_pool()
111 	struct ubi_fm_pool *pool = &ubi->fm_pool;  in wait_free_pebs_for_pool()
117 	 * 3. fm pebs - 1: Twice fastmap size deducted by fastmap and fm_anchor  in wait_free_pebs_for_pool()
118 	 * 4. beb_rsvd_pebs: This value should be get under lock ubi->wl_lock  in wait_free_pebs_for_pool()
121 		       ubi->fm_size / ubi->leb_size - 1 + ubi->fm_pool_rsv_cnt;  in wait_free_pebs_for_pool()
124 		spin_lock(&ubi->wl_lock);  in wait_free_pebs_for_pool()
125 		free = ubi->free_count;  in wait_free_pebs_for_pool()
126 		free += pool->size - pool->used + wl_pool->size - wl_pool->used;  in wait_free_pebs_for_pool()
127 		expect_free = reserved + ubi->beb_rsvd_pebs;  in wait_free_pebs_for_pool()
128 		spin_unlock(&ubi->wl_lock);  in wait_free_pebs_for_pool()
133 		 * -EBUSY is returned from mtd layer caused by system shutdown.  in wait_free_pebs_for_pool()
141  * left_free_count - returns the number of free pebs to fill fm pools
151 	if (!ubi->free.rb_node)  in left_free_count()
154 	if (!ubi->ro_mode && !ubi->fm_disabled)  in left_free_count()
155 		fm_used = ubi->fm_size / ubi->leb_size - 1;  in left_free_count()
157 	return ubi->free_count - fm_used;  in left_free_count()
161  * can_fill_pools - whether free PEBs will be left after filling pools
170 	struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool;  in can_fill_pools()
171 	struct ubi_fm_pool *pool = &ubi->fm_pool;  in can_fill_pools()
172 	int pool_need = pool->max_size - pool->size +  in can_fill_pools()
173 			wl_pool->max_size - wl_pool->size;  in can_fill_pools()
175 	if (free - pool_need < 1)  in can_fill_pools()
182  * ubi_refill_pools_and_lock - refills all fastmap PEB pools and takes fm locks.
187 	struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool;  in ubi_refill_pools_and_lock()
188 	struct ubi_fm_pool *pool = &ubi->fm_pool;  in ubi_refill_pools_and_lock()
192 	if (!ubi->ro_mode && !ubi->fm_disabled)  in ubi_refill_pools_and_lock()
195 	down_write(&ubi->fm_protect);  in ubi_refill_pools_and_lock()
196 	down_write(&ubi->work_sem);  in ubi_refill_pools_and_lock()
197 	down_write(&ubi->fm_eba_sem);  in ubi_refill_pools_and_lock()
199 	spin_lock(&ubi->wl_lock);  in ubi_refill_pools_and_lock()
204 	wl_pool->size = 0;  in ubi_refill_pools_and_lock()
205 	pool->size = 0;  in ubi_refill_pools_and_lock()
207 	if (ubi->fm_anchor) {  in ubi_refill_pools_and_lock()
208 		wl_tree_add(ubi->fm_anchor, &ubi->free);  in ubi_refill_pools_and_lock()
209 		ubi->free_count++;  in ubi_refill_pools_and_lock()
210 		ubi->fm_anchor = NULL;  in ubi_refill_pools_and_lock()
213 	if (!ubi->fm_disabled)  in ubi_refill_pools_and_lock()
215 		 * All available PEBs are in ubi->free, now is the time to get  in ubi_refill_pools_and_lock()
218 		ubi->fm_anchor = ubi_wl_get_fm_peb(ubi, 1);  in ubi_refill_pools_and_lock()
222 		if (pool->size < pool->max_size) {  in ubi_refill_pools_and_lock()
230 			pool->pebs[pool->size] = e->pnum;  in ubi_refill_pools_and_lock()
231 			pool->size++;  in ubi_refill_pools_and_lock()
235 		if (wl_pool->size < wl_pool->max_size) {  in ubi_refill_pools_and_lock()
241 			e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF,  in ubi_refill_pools_and_lock()
243 			self_check_in_wl_tree(ubi, e, &ubi->free);  in ubi_refill_pools_and_lock()
244 			rb_erase(&e->u.rb, &ubi->free);  in ubi_refill_pools_and_lock()
245 			ubi->free_count--;  in ubi_refill_pools_and_lock()
247 			wl_pool->pebs[wl_pool->size] = e->pnum;  in ubi_refill_pools_and_lock()
248 			wl_pool->size++;  in ubi_refill_pools_and_lock()
256 	wl_pool->used = 0;  in ubi_refill_pools_and_lock()
257 	pool->used = 0;  in ubi_refill_pools_and_lock()
259 	spin_unlock(&ubi->wl_lock);  in ubi_refill_pools_and_lock()
263  * produce_free_peb - produce a free physical eraseblock.
275 	while (!ubi->free.rb_node && ubi->works_count) {  in produce_free_peb()
287  * ubi_wl_get_peb - get a physical eraseblock.
292  * Returns with ubi->fm_eba_sem held in read mode!
297 	struct ubi_fm_pool *pool = &ubi->fm_pool;  in ubi_wl_get_peb()
298 	struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool;  in ubi_wl_get_peb()
301 	down_read(&ubi->fm_eba_sem);  in ubi_wl_get_peb()
302 	spin_lock(&ubi->wl_lock);  in ubi_wl_get_peb()
306 	if (pool->used == pool->size || wl_pool->used == wl_pool->size) {  in ubi_wl_get_peb()
307 		spin_unlock(&ubi->wl_lock);  in ubi_wl_get_peb()
308 		up_read(&ubi->fm_eba_sem);  in ubi_wl_get_peb()
312 			down_read(&ubi->fm_eba_sem);  in ubi_wl_get_peb()
313 			return -ENOSPC;  in ubi_wl_get_peb()
315 		down_read(&ubi->fm_eba_sem);  in ubi_wl_get_peb()
316 		spin_lock(&ubi->wl_lock);  in ubi_wl_get_peb()
319 	if (pool->used == pool->size) {  in ubi_wl_get_peb()
320 		spin_unlock(&ubi->wl_lock);  in ubi_wl_get_peb()
324 			ret = -ENOSPC;  in ubi_wl_get_peb()
327 		up_read(&ubi->fm_eba_sem);  in ubi_wl_get_peb()
330 			down_read(&ubi->fm_eba_sem);  in ubi_wl_get_peb()
336 	ubi_assert(pool->used < pool->size);  in ubi_wl_get_peb()
337 	ret = pool->pebs[pool->used++];  in ubi_wl_get_peb()
338 	prot_queue_add(ubi, ubi->lookuptbl[ret]);  in ubi_wl_get_peb()
339 	spin_unlock(&ubi->wl_lock);  in ubi_wl_get_peb()
345  * next_peb_for_wl - returns next PEB to be used internally by the
346  * WL sub-system.
349  * @need_fill: whether to fill wear-leveling pool when no PEBs are found
354 	struct ubi_fm_pool *pool = &ubi->fm_wl_pool;  in next_peb_for_wl()
357 	if (pool->used == pool->size) {  in next_peb_for_wl()
358 		if (need_fill && !ubi->fm_work_scheduled) {  in next_peb_for_wl()
365 			ubi->fm_work_scheduled = 1;  in next_peb_for_wl()
366 			schedule_work(&ubi->fm_work);  in next_peb_for_wl()
371 	pnum = pool->pebs[pool->used];  in next_peb_for_wl()
372 	return ubi->lookuptbl[pnum];  in next_peb_for_wl()
376  * need_wear_leveling - checks whether to trigger a wear leveling work.
378  * and 'ubi->free', because free PEB in 'ubi->free' tree maybe moved into
388 	if (!ubi->used.rb_node)  in need_wear_leveling()
393 		if (!ubi->free.rb_node)  in need_wear_leveling()
395 		e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF, 0);  in need_wear_leveling()
396 		ec = e->ec;  in need_wear_leveling()
398 		ec = e->ec;  in need_wear_leveling()
399 		if (ubi->free.rb_node) {  in need_wear_leveling()
400 			e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF, 0);  in need_wear_leveling()
401 			ec = max(ec, e->ec);  in need_wear_leveling()
404 	e = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, u.rb);  in need_wear_leveling()
406 	return ec - e->ec >= UBI_WL_THRESHOLD;  in need_wear_leveling()
409 /* get_peb_for_wl - returns a PEB to be used internally by the WL sub-system.
415 	struct ubi_fm_pool *pool = &ubi->fm_wl_pool;  in get_peb_for_wl()
418 	ubi_assert(rwsem_is_locked(&ubi->fm_eba_sem));  in get_peb_for_wl()
420 	if (pool->used == pool->size) {  in get_peb_for_wl()
424 		if (!ubi->fm_work_scheduled) {  in get_peb_for_wl()
425 			ubi->fm_work_scheduled = 1;  in get_peb_for_wl()
426 			schedule_work(&ubi->fm_work);  in get_peb_for_wl()
431 	pnum = pool->pebs[pool->used++];  in get_peb_for_wl()
432 	return ubi->lookuptbl[pnum];  in get_peb_for_wl()
436  * ubi_ensure_anchor_pebs - schedule wear-leveling to produce an anchor PEB.
444 	spin_lock(&ubi->wl_lock);  in ubi_ensure_anchor_pebs()
447 	if (ubi->fm_anchor) {  in ubi_ensure_anchor_pebs()
448 		spin_unlock(&ubi->wl_lock);  in ubi_ensure_anchor_pebs()
455 		ubi->fm_anchor = anchor;  in ubi_ensure_anchor_pebs()
456 		spin_unlock(&ubi->wl_lock);  in ubi_ensure_anchor_pebs()
460 	ubi->fm_do_produce_anchor = 1;  in ubi_ensure_anchor_pebs()
461 	/* No luck, trigger wear leveling to produce a new anchor PEB. */  in ubi_ensure_anchor_pebs()
462 	if (ubi->wl_scheduled) {  in ubi_ensure_anchor_pebs()
463 		spin_unlock(&ubi->wl_lock);  in ubi_ensure_anchor_pebs()
466 	ubi->wl_scheduled = 1;  in ubi_ensure_anchor_pebs()
467 	spin_unlock(&ubi->wl_lock);  in ubi_ensure_anchor_pebs()
471 		spin_lock(&ubi->wl_lock);  in ubi_ensure_anchor_pebs()
472 		ubi->wl_scheduled = 0;  in ubi_ensure_anchor_pebs()
473 		spin_unlock(&ubi->wl_lock);  in ubi_ensure_anchor_pebs()
474 		return -ENOMEM;  in ubi_ensure_anchor_pebs()
477 	wrk->func = &wear_leveling_worker;  in ubi_ensure_anchor_pebs()
483  * ubi_wl_put_fm_peb - returns a PEB used in a fastmap to the wear-leveling
484  * sub-system.
496 	int vol_id, pnum = fm_e->pnum;  in ubi_wl_put_fm_peb()
501 	ubi_assert(pnum < ubi->peb_count);  in ubi_wl_put_fm_peb()
503 	spin_lock(&ubi->wl_lock);  in ubi_wl_put_fm_peb()
504 	e = ubi->lookuptbl[pnum];  in ubi_wl_put_fm_peb()
512 		ubi_assert(e->ec >= 0);  in ubi_wl_put_fm_peb()
513 		ubi->lookuptbl[pnum] = e;  in ubi_wl_put_fm_peb()
516 	spin_unlock(&ubi->wl_lock);  in ubi_wl_put_fm_peb()
523  * ubi_is_erase_work - checks whether a work is erase work.
528 	return wrk->func == erase_worker;  in ubi_is_erase_work()
535 	return_unused_pool_pebs(ubi, &ubi->fm_pool);  in ubi_fastmap_close()
536 	return_unused_pool_pebs(ubi, &ubi->fm_wl_pool);  in ubi_fastmap_close()
538 	if (ubi->fm_anchor) {  in ubi_fastmap_close()
539 		return_unused_peb(ubi, ubi->fm_anchor);  in ubi_fastmap_close()
540 		ubi->fm_anchor = NULL;  in ubi_fastmap_close()
543 	if (ubi->fm) {  in ubi_fastmap_close()
544 		for (i = 0; i < ubi->fm->used_blocks; i++)  in ubi_fastmap_close()
545 			kfree(ubi->fm->e[i]);  in ubi_fastmap_close()
547 	kfree(ubi->fm);  in ubi_fastmap_close()
551  * may_reserve_for_fm - tests whether a PEB shall be reserved for fastmap.
561 	if (e && !ubi->fm_disabled && !ubi->fm && !ubi->fm_anchor &&  in may_reserve_for_fm()
562 	    e->pnum < UBI_FM_MAX_START)  in may_reserve_for_fm()
563 		e = rb_entry(rb_next(root->rb_node),  in may_reserve_for_fm()