[Sheepdog] [PATCH v3] abstract store IO interface

[Liu Yuan]

On 11/17/2011 04:54 PM, Liu Yuan wrote:

> This is an atemp to abstract store IO interface to adopt sheepdog to more
> kv-stores.
> 
> changes v3:
>  - use io control structure to pass internal information between interfaces. This 
>    aims to make interface more generic and flexible.
>  - move fallocate() and ftruncate() into default store's open. This aims to remove 
>    higher level code's awareness of store's internal iocb.
>  - rename store_write_obj_fd into do_write_obj.
>  - split simple store out of store.c
> 


miss below update:
   for journel.c
 - split journel_perform() into journel_begin() and journel_end()

> changes v2:
>  - use void pointer for private data transfer.
>  - open: return the return value, and the private data in the argument.
>  - open: use create flag for creating new file instead of posix flags.
> 
>  As is sugguested by Christoph Hellwig. Thanks!
> 
>  - read/write: use xpread/xpwrite for short rw and other conditions, but
>    not return SD_RES_EIO, just retrn -1 in error case as system call read/write.
> 
> Thanks,
> Yuan