UBIFS: fix available blocks count
Take into account that 2 eraseblocks are never available because
they are reserved for the index. This gives more realistic count
of FS blocks.
To avoid future confusions like this, introduce a constant.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c
index d5a6503..e423425 100644
--- a/fs/ubifs/budget.c
+++ b/fs/ubifs/budget.c
@@ -280,13 +280,8 @@
* extra LEB to compensate.
*/
ret += 1;
- /*
- * At present the index needs at least 2 LEBs: one for the index head
- * and one for in-the-gaps method (which currently does not cater for
- * the index head and so excludes it from consideration).
- */
- if (ret < 2)
- ret = 2;
+ if (ret < MIN_INDEX_LEBS)
+ ret = MIN_INDEX_LEBS;
return ret;
}
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 2dbaa4f..a6a7798 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -695,9 +695,10 @@
* necessary to report something for the 'statfs()' call.
*
* Subtract the LEB reserved for GC, the LEB which is reserved for
- * deletions, and assume only one journal head is available.
+ * deletions, minimum LEBs for the index, and assume only one journal
+ * head is available.
*/
- tmp64 = c->main_lebs - 2 - c->jhead_cnt + 1;
+ tmp64 = c->main_lebs - 1 - 1 - MIN_INDEX_LEBS - c->jhead_cnt + 1;
tmp64 *= (uint64_t)c->leb_size - c->leb_overhead;
tmp64 = ubifs_reported_space(c, tmp64);
c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT;
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index f8ef7c1..543e850 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -63,6 +63,14 @@
#define SQNUM_WARN_WATERMARK 0xFFFFFFFF00000000ULL
#define SQNUM_WATERMARK 0xFFFFFFFFFF000000ULL
+/*
+ * Minimum amount of LEBs reserved for the index. At present the index needs at
+ * least 2 LEBs: one for the index head and one for in-the-gaps method (which
+ * currently does not cater for the index head and so excludes it from
+ * consideration).
+ */
+#define MIN_INDEX_LEBS 2
+
/* Minimum amount of data UBIFS writes to the flash */
#define MIN_WRITE_SZ (UBIFS_DATA_NODE_SZ + 8)