Re: [osd-dev] [PATCH 1/9] exofs: osd Swiss army knife

Boaz Harrosh
2009-01-13T14:43:57Z

Alan Cox wrote:
>>> +#define EXOFS_SUPER_ID 0x10000 /* object ID for on-disk superblock */
>
> And if an OS failure breaks the super block and you have only one how do
> you recover it ?

There is nothing really in this object but the "next_id" which is recoverable
by an fsck utility (Not yet submitted) by a simple osd-list-partition
command. Same for num-of-files. All these values are just cached values,
for convenience.

>
>>> +#define EXOFS_BM_ID 0x10001 /* object ID for ID bitmap */
Not used will be dropped

>>> +#define EXOFS_ROOT_ID 0x10002 /* object ID for root directory */
OK Only one, but so is all other directories. I'll think about it.
I'll probably postpone it for together with the raid management.

>>> +#define EXOFS_TEST_ID 0x10003 /* object ID for test object */
Not used will be dropped

>
> Ditto some of the others
>
>>> + EXOFS_UINT64_MAX = (~0LL),
>>> + EXOFS_MAX_INO_ID = (sizeof(ino_t) * 8 == 64) ? EXOFS_UINT64_MAX :
>>> + (1LL << (sizeof(ino_t) * 8 - 1)),
>
> Ok so thats quite a big number
>
>>> + uint32_t s_nextid; /* Highest object ID used */
I fixed all that to be __le64, you can see that on the web here:
http://git.open-osd.org/gitweb.cgi?p=open-osd.git;a=shortlog;h=refs/heads/exofs

I will submit another round ASAP. I'm currently busy with user-mode-library.
Once done I'll post the next exofs round. All these and lots of other areas where
converted to proper __leXX types. Specially the directory code had all these
missing. It was all triggered thanks to Morton who pointed me to all these ext2
bug-fixes since 2.6.10.

>
> but that is a smaller one
>
>>> + uint32_t s_numfiles; /* Number of files on fs */
>
> as is this

Yes also fixed to __le64

>
>>> + uint32_t i_atime; /* Access time */
>>> + uint32_t i_ctime; /* Creation time */
>>> + uint32_t i_mtime; /* Modification time */
>
> 2038 ? - bits are cheap
>

OK Avisi got lazy, This is a copy form ext2. I will fix that,
thanks for pointing this out. I will put __le64 for seconds
and also add __le64 for nanoseconds while at it.

Thanks Ingo for your review
Boaz