On Thu, 26 Aug 2004 19:20:09 +0400, Brad Campbell <brad@xxxxxxxxxxx> wrote:
G'day all,
Hot on the trail of this libata oddity.
ATA_MAX_SECTORS == 200.
Should then the scsi layer be able to do this and queue 1/2 a Meg in a single request?
Am I looking at something completely weird? Is the block layer doing something I should know about? Can SATA transfers handle 1024 sectors in one go? Will Batman make it out of the cave alive?
That is decimal 200, not hex 200. Technically with ATA (or SATA) drives you can bump it to 0x100 (256). That is the limitation of LBA28 drives. With LBA48 drives you can do 0xffff (64k) sectors per request I believe.
G'day Dave,
Thanks for the reply.
In theory I guess 0xffff sectors is possible. Over here, I'm getting requests of more than 256 sectors intermittently locking up my SATA->PATA converters if run on a via sata interface (On a promise interface it's not a problem)
I also note than in sata_sil there is a workaround for Seagate drives that knocks max_sectors back to 15. Is the md driver going to circumvent that also and lock up those interfaces?
I realise that 200 is decimal, my question was more how are requests of 1024 sectors making it to the driver when the driver has a max_sector value of 200?
I'm only seeing sectors > 200 when the request comes from md, thus my cc'ing it to the raid list to see if anyone there has any idea.
Regards, Brad (Getting warmer) - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
