Logfs: Allow NULL block_isbad() methods

Not all mtd drivers define block_isbad().  Let's assume no bad blocks
instead of refusing to mount.

Signed-off-by: Joern Engel <joern@logfs.org>

1 files changed, 12 insertions, 14 deletions

diff --git a/fs/logfs/dev_mtd.c b/fs/logfs/dev_mtd.c
index 339e17e9133d..d054d7e975ca 100644
--- a/fs/logfs/dev_mtd.c
+++ b/fs/logfs/dev_mtd.c
@@ -150,14 +150,13 @@ static struct page *mtd_find_first_sb(struct super_block *sb, u64 *ofs)
         filler_t *filler = mtd_readpage;
         struct mtd_info *mtd = super->s_mtd;
 
-        if (!mtd->block_isbad)
-                return NULL;
-
         *ofs = 0;
-        while (mtd->block_isbad(mtd, *ofs)) {
-                *ofs += mtd->erasesize;
-                if (*ofs >= mtd->size)
-                        return NULL;
+        if (mtd->block_isbad) {
+                while (mtd->block_isbad(mtd, *ofs)) {
+                        *ofs += mtd->erasesize;
+                        if (*ofs >= mtd->size)
+                                return NULL;
+                }
         }
         BUG_ON(*ofs & ~PAGE_MASK);
         return read_cache_page(mapping, *ofs >> PAGE_SHIFT, filler, sb);
@@ -170,14 +169,13 @@ static struct page *mtd_find_last_sb(struct super_block *sb, u64 *ofs)
         filler_t *filler = mtd_readpage;
         struct mtd_info *mtd = super->s_mtd;
 
-        if (!mtd->block_isbad)
-                return NULL;
-
         *ofs = mtd->size - mtd->erasesize;
-        while (mtd->block_isbad(mtd, *ofs)) {
-                *ofs -= mtd->erasesize;
-                if (*ofs <= 0)
-                        return NULL;
+        if (mtd->block_isbad) {
+                while (mtd->block_isbad(mtd, *ofs)) {
+                        *ofs -= mtd->erasesize;
+                        if (*ofs <= 0)
+                                return NULL;
+                }
         }
         *ofs = *ofs + mtd->erasesize - 0x1000;
         BUG_ON(*ofs & ~PAGE_MASK);