mtd, ubi, ubifs: resync with Linux-3.14

[oweals/u-boot.git] / drivers / mtd / ubi / misc.c

diff --git a/drivers/mtd/ubi/misc.c b/drivers/mtd/ubi/misc.c
index 5ff55b4f77fea96c0a7236d82e4ad4a24e183fcc..49530b7448f9df8d7653658682b1a5dafe53b7ce 100644 (file)
--- a/drivers/mtd/ubi/misc.c
+++ b/drivers/mtd/ubi/misc.c
@@ -81,14 +81,62 @@ int ubi_check_volume(struct ubi_device *ubi, int vol_id)
 }
 
 /**
- * ubi_calculate_rsvd_pool - calculate how many PEBs must be reserved for bad
+ * ubi_update_reserved - update bad eraseblock handling accounting data.
+ * @ubi: UBI device description object
+ *
+ * This function calculates the gap between current number of PEBs reserved for
+ * bad eraseblock handling and the required level of PEBs that must be
+ * reserved, and if necessary, reserves more PEBs to fill that gap, according
+ * to availability. Should be called with ubi->volumes_lock held.
+ */
+void ubi_update_reserved(struct ubi_device *ubi)
+{
+       int need = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
+
+       if (need <= 0 || ubi->avail_pebs == 0)
+               return;
+
+       need = min_t(int, need, ubi->avail_pebs);
+       ubi->avail_pebs -= need;
+       ubi->rsvd_pebs += need;
+       ubi->beb_rsvd_pebs += need;
+       ubi_msg("reserved more %d PEBs for bad PEB handling", need);
+}
+
+/**
+ * ubi_calculate_reserved - calculate how many PEBs must be reserved for bad
  * eraseblock handling.
  * @ubi: UBI device description object
  */
 void ubi_calculate_reserved(struct ubi_device *ubi)
 {
-       ubi->beb_rsvd_level = ubi->good_peb_count/100;
-       ubi->beb_rsvd_level *= CONFIG_MTD_UBI_BEB_RESERVE;
-       if (ubi->beb_rsvd_level < MIN_RESEVED_PEBS)
-               ubi->beb_rsvd_level = MIN_RESEVED_PEBS;
+       /*
+        * Calculate the actual number of PEBs currently needed to be reserved
+        * for future bad eraseblock handling.
+        */
+       ubi->beb_rsvd_level = ubi->bad_peb_limit - ubi->bad_peb_count;
+       if (ubi->beb_rsvd_level < 0) {
+               ubi->beb_rsvd_level = 0;
+               ubi_warn("number of bad PEBs (%d) is above the expected limit (%d), not reserving any PEBs for bad PEB handling, will use available PEBs (if any)",
+                        ubi->bad_peb_count, ubi->bad_peb_limit);
+       }
+}
+
+/**
+ * ubi_check_pattern - check if buffer contains only a certain byte pattern.
+ * @buf: buffer to check
+ * @patt: the pattern to check
+ * @size: buffer size in bytes
+ *
+ * This function returns %1 in there are only @patt bytes in @buf, and %0 if
+ * something else was also found.
+ */
+int ubi_check_pattern(const void *buf, uint8_t patt, int size)
+{
+       int i;
+
+       for (i = 0; i < size; i++)
+               if (((const uint8_t *)buf)[i] != patt)
+                       return 0;
+       return 1;
 }