On Mon, 2006-11-06 at 18:26 -0600, Steve French wrote: > I assumed that the original intent of the "inode diet patch" was to > remove fields in the inode, > which most filesystems can get out of the superblock. I think I may have planted the idea that you could get i_blkbits from sb->s_blocksize_bits, but I was wrong. Consider a block device. It's blocksize is not related to the superblock of its containing filesystem. > If > inode->blksize and inode->blkbits were > related (2**blkbits == blksize) , it also makes sense to me that someone > (Ted?) removed one and left the other > as one would be redundant, They were never really related. Some filesystems treated them as if they were, but the vfs always used i_blkbits for the block size. i_blksize was only really used for returning stat->blksize. > but some filesystems like cifs have a large > recommended i/o size (16K), > but if someone wants to remove both from the inode that is fine by me, > as long as cifs > stat->blksize is set as you suggested on the way out of cifs_getattr. > Eventually cifs should set > the stat->blksize to a smaller value for one rarer case. For the most > common case > cifs should still set it to 16K (CIFS_MAX_MSGSIZE) as that is the most > common negotiated > buffer size but if the server does not negotiate large read support, and > the server also is so old > that it negotiates a buffer size smaller than 16K (e.g. Windows95 > negotiates 2K IIRC) > then we could set stat-blksize to the smaller negotiated buffer size - > but since those servers are > getting rarer it is probably not that important. More interesting > will be the future cases in > which we will be able to set this value larger to more servers, as in > general for modern > network adapters, the larger network i/o size the better. It would probably be best to just set stat->blksize to the negotiated buffer size. -- David Kleikamp IBM Linux Technology Center - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
