ubifs: Raise write version to 5

[sfrench/cifs-2.6.git] / fs / ubifs / sb.c

diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c
index 3cbb904a6d7d92fe4b72b73861a73d5380fee369..7f1ead29e7270a39374bef080035beaf42374820 100644 (file)
--- a/fs/ubifs/sb.c
+++ b/fs/ubifs/sb.c
@@ -163,6 +163,7 @@ static int create_default_filesystem(struct ubifs_info *c)
        tmp64 = (long long)max_buds * c->leb_size;
        if (big_lpt)
                sup_flags |= UBIFS_FLG_BIGLPT;
+       sup_flags |= UBIFS_FLG_DOUBLE_HASH;
 
        sup->ch.node_type  = UBIFS_SB_NODE;
        sup->key_hash      = UBIFS_KEY_HASH_R5;
@@ -465,6 +466,16 @@ static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup)
                goto failed;
        }
 
+       if (!c->double_hash && c->fmt_version >= 5) {
+               err = 16;
+               goto failed;
+       }
+
+       if (c->encrypted && c->fmt_version < 5) {
+               err = 17;
+               goto failed;
+       }
+
        return 0;
 
 failed:
@@ -620,6 +631,24 @@ int ubifs_read_superblock(struct ubifs_info *c)
        memcpy(&c->uuid, &sup->uuid, 16);
        c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
        c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP);
+       c->double_hash = !!(sup_flags & UBIFS_FLG_DOUBLE_HASH);
+       c->encrypted = !!(sup_flags & UBIFS_FLG_ENCRYPTION);
+
+       if ((sup_flags & ~UBIFS_FLG_MASK) != 0) {
+               ubifs_err(c, "Unknown feature flags found: %#x",
+                         sup_flags & ~UBIFS_FLG_MASK);
+               err = -EINVAL;
+               goto out;
+       }
+
+#ifndef CONFIG_UBIFS_FS_ENCRYPTION
+       if (c->encrypted) {
+               ubifs_err(c, "file system contains encrypted files but UBIFS"
+                            " was built without crypto support.");
+               err = -EINVAL;
+               goto out;
+       }
+#endif
 
        /* Automatically increase file system size to the maximum size */
        c->old_leb_cnt = c->leb_cnt;
@@ -807,3 +836,33 @@ int ubifs_fixup_free_space(struct ubifs_info *c)
        ubifs_msg(c, "free space fixup complete");
        return err;
 }
+
+int ubifs_enable_encryption(struct ubifs_info *c)
+{
+       int err;
+       struct ubifs_sb_node *sup;
+
+       if (c->encrypted)
+               return 0;
+
+       if (c->ro_mount || c->ro_media)
+               return -EROFS;
+
+       if (c->fmt_version < 5) {
+               ubifs_err(c, "on-flash format version 5 is needed for encryption");
+               return -EINVAL;
+       }
+
+       sup = ubifs_read_sb_node(c);
+       if (IS_ERR(sup))
+               return PTR_ERR(sup);
+
+       sup->flags |= cpu_to_le32(UBIFS_FLG_ENCRYPTION);
+
+       err = ubifs_write_sb_node(c, sup);
+       if (!err)
+               c->encrypted = 1;
+       kfree(sup);
+
+       return err;
+}