Re: [PATCH] udf : skip mirror metadata FE since metadata FE is ok.

[NamJae Jeon <linkinjeon@gmail.com>]

2011/10/21 Jan Kara <jack@suse.cz>:
> On Thu 20-10-11 00:03:18, Namjae Jeon wrote:
>> By Jan Kara's suggestion, This patch skip mirror metadata FE since
>> metadata FE is ok. And try to read it only the first time
>> udf_get_pblock_meta25() fails to map the block from metadata FE.
>>
>> Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
>> Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com>
>> ---
>>  fs/udf/partition.c |   20 ++++++++++++++++++++
>>  fs/udf/super.c     |   33 ++++++++++++++++-----------------
>>  2 files changed, 36 insertions(+), 17 deletions(-)
>>
>> diff --git a/fs/udf/partition.c b/fs/udf/partition.c
>> index f3e472c..8bfc25b 100644
>> --- a/fs/udf/partition.c
>> +++ b/fs/udf/partition.c
>> @@ -311,6 +311,7 @@ uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block,
>>       struct udf_meta_data *mdata;
>>       uint32_t retblk;
>>       struct inode *inode;
>> +     struct kernel_lb_addr addr;
>>
>>       udf_debug("READING from METADATA\n");
>>
>> @@ -323,6 +324,25 @@ uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block,
>>       retblk = udf_try_read_meta(inode, block, partition, offset);
>>       if (retblk == 0xFFFFFFFF) {
>>               udf_warn(sb, "error reading from METADATA, trying to read from MIRROR\n");
>> +             if (mdata->s_mirror_fe == NULL) {
>  This won't be good because if s_mirror_fe cannot be loaded as well, you'd
> just try loading it on every block mapping which failed from the primary
> metadata map. So you should have a flag somewhere whether in mdata, whether
> you tried loading mirror_fe or not and use that.
>
>> +                     /* mirror file entry */
>> +                     addr.logicalBlockNum = mdata->s_mirror_file_loc;
>> +                     addr.partitionReferenceNum = map->s_partition_num;
>> +                     udf_debug("Mirror metadata file location: block = %d part = %d\n",
>> +                             addr.logicalBlockNum,
>> +                             addr.partitionReferenceNum);
>> +                     mdata->s_mirror_fe = udf_iget(sb, &addr);
>> +
>> +                     if (mdata->s_mirror_fe == NULL)
>> +                             udf_err(sb, "mirror inode efe not found");
>> +                     else if (UDF_I(mdata->s_mirror_fe)->i_alloc_type !=
>> +                                     ICBTAG_FLAG_AD_SHORT) {
>> +                             udf_warn(sb, "mirror inode efe does not have short allocation descriptors!\n");
>> +                             iput(mdata->s_mirror_fe);
>> +                             mdata->s_mirror_fe = NULL;
>> +                     }
>  Also please create a helper function for loading metadata/mirror metadat
> FE so that we don't have loading duplicated in three places... Thanks.
Hi Jan.
Thanks for your review.
I will do it.

>
>                                                                Honza
> --
> Jan Kara <jack@suse.cz>
> SUSE Labs, CR
>