udf: allow implicit blocksize specification during mount
udf_fill_super() used udf_parse_options() to flag UDF_FLAG_BLOCKSIZE_SET
when blocksize was specified otherwise used 512 bytes
(bdev_logical_block_size) and 2048 bytes (UDF_DEFAULT_BLOCKSIZE)
IOW both 1024 and 4096 specifications were required or resulted in
"mount: wrong fs type, bad option, bad superblock on /dev/loop1"
This patch loops through different block values but also updates
udf_load_vrs() to return -EINVAL instead of 0 when udf_check_vsd()
fails (and uopt->novrs = 0).
The later being the reason for the RFC; we have that case when mounting
a 4kb blocksize against other values but maybe VRS is not mandatory
there ?
Tested with 512, 1024, 2048 and 4096 blocksize
Reported-by: Jan Kara <jack@suse.com>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/udf/super.c b/fs/udf/super.c
index 6b5a1a4..14b4bc1 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1955,7 +1955,7 @@ static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
if (!nsr_off) {
if (!silent)
udf_warn(sb, "No VRS found\n");
- return 0;
+ return -EINVAL;
}
if (nsr_off == -1)
udf_debug("Failed to read sector at offset %d. "
@@ -2159,15 +2159,25 @@ static int udf_fill_super(struct super_block *sb, void *options, int silent)
ret = udf_load_vrs(sb, &uopt, silent, &fileset);
} else {
uopt.blocksize = bdev_logical_block_size(sb->s_bdev);
- ret = udf_load_vrs(sb, &uopt, silent, &fileset);
- if (ret == -EAGAIN && uopt.blocksize != UDF_DEFAULT_BLOCKSIZE) {
- if (!silent)
- pr_notice("Rescanning with blocksize %d\n",
- UDF_DEFAULT_BLOCKSIZE);
- brelse(sbi->s_lvid_bh);
- sbi->s_lvid_bh = NULL;
- uopt.blocksize = UDF_DEFAULT_BLOCKSIZE;
+ while (uopt.blocksize <= 4096) {
ret = udf_load_vrs(sb, &uopt, silent, &fileset);
+ if (ret < 0) {
+ if (!silent && ret != -EACCES) {
+ pr_notice("Scanning with blocksize %d failed\n",
+ uopt.blocksize);
+ }
+ brelse(sbi->s_lvid_bh);
+ sbi->s_lvid_bh = NULL;
+ /*
+ * EACCES is special - we want to propagate to
+ * upper layers that we cannot handle RW mount.
+ */
+ if (ret == -EACCES)
+ break;
+ } else
+ break;
+
+ uopt.blocksize <<= 1;
}
}
if (ret < 0) {
