linux-scsi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH 0/2] sg_ring: Gentler scsi merge
@ 2008-01-03  7:00 Rusty Russell
  2008-01-03  8:50 ` [PATCH 1/3] scsi: Convert everyone to scsi_sglist and scsi_sg_count Rusty Russell
  2008-01-03  9:42 ` [PATCH 0/2] sg_ring: Gentler scsi merge Boaz Harrosh
  0 siblings, 2 replies; 7+ messages in thread
From: Rusty Russell @ 2008-01-03  7:00 UTC (permalink / raw)
  To: Jens Axboe; +Cc: linux-scsi

OK, after wading through many scsi drivers, I decided to change tack and try 
to provide a transition path.  This is in two stages:

1) These two patches.  sg_ring used underneath, but if any driver asks for 
scsi_sglist() they get a 2.6.24-style chained sg.  No other patches are 
necessary.

2) Once all chained-sg-needing scsi drivers change to use cmd->sg (ie. 
sg_ring) directly, and the chained sg patches can be reverted.  scsi_sglist() 
and scsi_sg_count() then become:

	/* You should only use these if you never need chained sgs */
	static inline struct scatterlist *scsi_sglist(struct scsi_cmd *cmd)
	{
		BUG_ON(!list_empty(&cmd->sg->list));
		return &cmd->sg->sg[0];
	}

	static unsigned int scsi_sg_count(struct scsi_cmd *cmd)
	{
		if (!cmd->sg)
			return 0;
		BUG_ON(!list_empty(&cmd->sg->list));
		return cmd->sg->num;
	}

Thanks,
Rusty.

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2008-01-04  3:28 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2008-01-03  7:00 [PATCH 0/2] sg_ring: Gentler scsi merge Rusty Russell
2008-01-03  8:50 ` [PATCH 1/3] scsi: Convert everyone to scsi_sglist and scsi_sg_count Rusty Russell
2008-01-03  8:54   ` [PATCH 2/3] usb_storage: usb_stor_bulk_transfer_sg cleanup Rusty Russell
2008-01-03  8:55     ` [PATCH 3/3] scsi: convert core to sg_ring Rusty Russell
2008-01-03  9:26   ` [PATCH 1/3] scsi: Convert everyone to scsi_sglist and scsi_sg_count Boaz Harrosh
2008-01-04  3:28     ` Rusty Russell
2008-01-03  9:42 ` [PATCH 0/2] sg_ring: Gentler scsi merge Boaz Harrosh

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).