Re: [PATCH 2/2] completely convert sg to block layer helpers

[Mike Christie <michaelc@cs.wisc.edu>]

Mike Christie wrote:
> Mike Christie wrote:
>> any missing functionality. I am still testing the patch. I have not
>> tested some of the older sg interfaces
> 
> I am pretty sure (100% :)), that I messed up the old interface handling.
> 
>> -
>> -static int
>> -sg_write_xfer(Sg_request * srp)
>> -{
>> -	sg_io_hdr_t *hp = &srp->header;
>> -	Sg_scatter_hold *schp = &srp->data;
>> -	struct scatterlist *sg = schp->buffer;
>> -	int num_xfer = 0;
>> -	int j, k, onum, usglen, ksglen, res;
>> -	int iovec_count = (int) hp->iovec_count;
>> -	int dxfer_dir = hp->dxfer_direction;
>> -	unsigned char *p;
>> -	unsigned char __user *up;
>> -	int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
>> -
>> -	if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
>> -	    (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
>> -		num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
>> -		if (schp->bufflen < num_xfer)
>> -			num_xfer = schp->bufflen;
> 
> In sg_write_xfer here, for the old interface is it valid to have
> hp->dxfer_len greater than hp->flags, then have sg_read_oxfer get
> num_read_xfer that is not equal to hp->dxfer_len?

Could num_read_xfer would also not be equal to hp->flags, so three
different values?