Re: [PATCH 4 of 8] sd: Physical block size and alignment support

["Martin K. Petersen" <martin.petersen@oracle.com>]

>>>>> "Konrad" == Konrad Rzeszutek <konrad@virtualiron.com> writes:

[Printing physical block size]

Konrad> With the changes in the read_capacity_16 (where you set the
Konrad> hw_sector_size) this won't be printed (at least on first probe).

Why not?

[root@10 ~]# modprobe scsi_debug dev_size_mb=1024 num_parts=4 physblk_exp=3
scsi 6:0:0:0: Direct-Access     Linux    scsi_debug       0004 PQ: 0 ANSI: 5
sd 6:0:0:0: Attached scsi generic sg3 type 0
sd 6:0:0:0: [sdc] 2097152 512-byte logical blocks: (1.07 GB/1.00 GiB)
sd 6:0:0:0: [sdc] 4096-byte physical blocks


Konrad> Another question - should the Documentation/*.txt have an entry
Konrad> about what a 'logical block', and 'physical block' is
Konrad> vs. 'hardware sector' ?

Well, another item on my todo list is to kill the notion of hardware
sector completely.  The protocols have been referring to logical blocks
for ages.

It hasn't been a big problem until now because logical block size has
been equal to the hardware sector size.  That's no longer a valid
assumption.

-- 
Martin K. Petersen	Oracle Linux Engineering