1 files changed, 30 insertions, 18 deletions

diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 26a214f016c1..a357f3d27f2f 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -181,11 +181,13 @@ static void wl_entry_destroy(struct ubi_device *ubi, struct ubi_wl_entry *e)
 /**
  * do_work - do one pending work.
  * @ubi: UBI device description object
+ * @executed: whether there is one work is executed
  *
  * This function returns zero in case of success and a negative error code in
- * case of failure.
+ * case of failure. If @executed is not NULL and there is one work executed,
+ * @executed is set as %1, otherwise @executed is set as %0.
  */
-static int do_work(struct ubi_device *ubi)
+static int do_work(struct ubi_device *ubi, int *executed)
 {
 	int err;
 	struct ubi_work *wrk;
@@ -203,9 +205,13 @@ static int do_work(struct ubi_device *ubi)
 	if (list_empty(&ubi->works)) {
 		spin_unlock(&ubi->wl_lock);
 		up_read(&ubi->work_sem);
+		if (executed)
+			*executed = 0;
 		return 0;
 	}
 
+	if (executed)
+		*executed = 1;
 	wrk = list_entry(ubi->works.next, struct ubi_work, list);
 	list_del(&wrk->list);
 	ubi->works_count -= 1;
@@ -311,12 +317,14 @@ static void prot_queue_add(struct ubi_device *ubi, struct ubi_wl_entry *e)
  * @ubi: UBI device description object
  * @root: the RB-tree where to look for
  * @diff: maximum possible difference from the smallest erase counter
+ * @pick_max: pick PEB even its erase counter beyonds 'min_ec + @diff'
  *
  * This function looks for a wear leveling entry with erase counter closest to
  * min + @diff, where min is the smallest erase counter.
  */
 static struct ubi_wl_entry *find_wl_entry(struct ubi_device *ubi,
-					  struct rb_root *root, int diff)
+					  struct rb_root *root, int diff,
+					  int pick_max)
 {
 	struct rb_node *p;
 	struct ubi_wl_entry *e;
@@ -330,9 +338,11 @@ static struct ubi_wl_entry *find_wl_entry(struct ubi_device *ubi,
 		struct ubi_wl_entry *e1;
 
 		e1 = rb_entry(p, struct ubi_wl_entry, u.rb);
-		if (e1->ec >= max)
+		if (e1->ec >= max) {
+			if (pick_max)
+				e = e1;
 			p = p->rb_left;
-		else {
+		} else {
 			p = p->rb_right;
 			e = e1;
 		}
@@ -361,12 +371,15 @@ static struct ubi_wl_entry *find_mean_wl_entry(struct ubi_device *ubi,
 	if (last->ec - first->ec < WL_FREE_MAX_DIFF) {
 		e = rb_entry(root->rb_node, struct ubi_wl_entry, u.rb);
 
-		/* If no fastmap has been written and this WL entry can be used
-		 * as anchor PEB, hold it back and return the second best
-		 * WL entry such that fastmap can use the anchor PEB later. */
+		/*
+		 * If no fastmap has been written and fm_anchor is not
+		 * reserved and this WL entry can be used as anchor PEB
+		 * hold it back and return the second best WL entry such
+		 * that fastmap can use the anchor PEB later.
+		 */
 		e = may_reserve_for_fm(ubi, e, root);
 	} else
-		e = find_wl_entry(ubi, root, WL_FREE_MAX_DIFF/2);
+		e = find_wl_entry(ubi, root, WL_FREE_MAX_DIFF/2, 0);
 
 	return e;
 }
@@ -427,7 +440,7 @@ static int prot_queue_del(struct ubi_device *ubi, int pnum)
 }
 
 /**
- * sync_erase - synchronously erase a physical eraseblock.
+ * ubi_sync_erase - synchronously erase a physical eraseblock.
  * @ubi: UBI device description object
  * @e: the physical eraseblock to erase
  * @torture: if the physical eraseblock has to be tortured
@@ -435,8 +448,7 @@ static int prot_queue_del(struct ubi_device *ubi, int pnum)
  * This function returns zero in case of success and a negative error code in
  * case of failure.
  */
-static int sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e,
-		      int torture)
+int ubi_sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, int torture)
 {
 	int err;
 	struct ubi_ec_hdr *ec_hdr;
@@ -1040,7 +1052,7 @@ static int ensure_wear_leveling(struct ubi_device *ubi, int nested)
 		 * %UBI_WL_THRESHOLD.
 		 */
 		e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, u.rb);
-		e2 = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF);
+		e2 = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF, 0);
 
 		if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD))
 			goto out_unlock;
@@ -1094,7 +1106,7 @@ static int __erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk)
 	dbg_wl("erase PEB %d EC %d LEB %d:%d",
 	       pnum, e->ec, wl_wrk->vol_id, wl_wrk->lnum);
 
-	err = sync_erase(ubi, e, wl_wrk->torture);
+	err = ubi_sync_erase(ubi, e, wl_wrk->torture);
 	if (!err) {
 		spin_lock(&ubi->wl_lock);
 
@@ -1686,7 +1698,7 @@ int ubi_thread(void *u)
 		}
 		spin_unlock(&ubi->wl_lock);
 
-		err = do_work(ubi);
+		err = do_work(ubi, NULL);
 		if (err) {
 			ubi_err(ubi, "%s: work failed with error code %d",
 				ubi->bgt_name, err);
@@ -1749,7 +1761,7 @@ static int erase_aeb(struct ubi_device *ubi, struct ubi_ainf_peb *aeb, bool sync
 	ubi->lookuptbl[e->pnum] = e;
 
 	if (sync) {
-		err = sync_erase(ubi, e, false);
+		err = ubi_sync_erase(ubi, e, false);
 		if (err)
 			goto out_free;
 
@@ -2071,7 +2083,7 @@ static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi)
 {
 	struct ubi_wl_entry *e;
 
-	e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF);
+	e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF, 0);
 	self_check_in_wl_tree(ubi, e, &ubi->free);
 	ubi->free_count--;
 	ubi_assert(ubi->free_count >= 0);
@@ -2097,7 +2109,7 @@ static int produce_free_peb(struct ubi_device *ubi)
 		spin_unlock(&ubi->wl_lock);
 
 		dbg_wl("do one work synchronously");
-		err = do_work(ubi);
+		err = do_work(ubi, NULL);
 
 		spin_lock(&ubi->wl_lock);
 		if (err)