linux-kernel - RE: [PATCH] dmaengine: dmatest: Add support for scatter-gather DMA mode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <C246CAC1457055469EF09E3A7AC4E11A4A5B4A17@XAP-PVEXMBX01.xlnx.xilinx.com>
Date:	Tue, 7 Jun 2016 06:08:59 +0000
From:	Appana Durga Kedareswara Rao <appana.durga.rao@...inx.com>
To:	Vinod Koul <vinod.koul@...el.com>
CC:	"dan.j.williams@...el.com" <dan.j.williams@...el.com>,
	"ramon.fried@...demg.com" <ramon.fried@...demg.com>,
	"dmaengine@...r.kernel.org" <dmaengine@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH] dmaengine: dmatest: Add support for scatter-gather DMA
 mode

Hi Vinod,

> >
> > +static unsigned int sg_sources = 1;
> > +module_param(sg_sources, uint, S_IRUGO | S_IWUSR);
> > +MODULE_PARM_DESC(sg_sources,
> 
> sg_buffers rather?

Ok sure will fix...

> 
> > +		"Number of scatter gather buffers (default: 1)");
> 
> blank line please

Ok

> 
> > +static unsigned int dmatest = 1;
> > +module_param(dmatest, uint, S_IRUGO | S_IWUSR);
> > +MODULE_PARM_DESC(dmatest,
> > +		"dmatest 0-memcpy 1-slave_sg (default: 1)");
> 
> dmatest? What does this mean!

To differentiate b/w the memcpy and slave_sg transfers using this dmatest 
Sysfs entry.

> 
> >  static unsigned int xor_sources = 3;
> >  module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
> > MODULE_PARM_DESC(xor_sources, @@ -431,6 +439,8 @@ static int
> > dmatest_func(void *data)
> >  	dev = chan->device;
> >  	if (thread->type == DMA_MEMCPY)
> >  		src_cnt = dst_cnt = 1;
> > +	else if (thread->type == DMA_SG)
> > +		src_cnt = dst_cnt = sg_sources;
> >  	else if (thread->type == DMA_XOR) {
> >  		/* force odd to ensure dst = src */
> >  		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
> @@ -485,6
> > +495,8 @@ static int dmatest_func(void *data)
> >  		dma_addr_t *dsts;
> >  		unsigned int src_off, dst_off, len;
> >  		u8 align = 0;
> > +		struct scatterlist tx_sg[src_cnt];
> > +		struct scatterlist rx_sg[src_cnt];
> >
> >  		total_tests++;
> >
> > @@ -577,10 +589,21 @@ static int dmatest_func(void *data)
> >  			um->bidi_cnt++;
> >  		}
> >
> > +		sg_init_table(tx_sg, src_cnt);
> > +		sg_init_table(rx_sg, dst_cnt);
> 
> why dst_cnt  here wheras you used src_cnt to create the list!

dst_cnt is used in prep_dma_sg will use dst_cnt to created list for rx buffers
Will fix this in v2.

> 
> > +		for (i = 0; i < src_cnt; i++) {
> > +			sg_dma_address(&rx_sg[i]) = srcs[i];
> > +			sg_dma_address(&tx_sg[i]) = dsts[i] + dst_off;
> > +			sg_dma_len(&tx_sg[i]) = len;
> > +			sg_dma_len(&rx_sg[i]) = len;
> > +		}
> >  		if (thread->type == DMA_MEMCPY)
> >  			tx = dev->device_prep_dma_memcpy(chan,
> >  							 dsts[0] + dst_off,
> >  							 srcs[0], len, flags);
> > +		else if (thread->type == DMA_SG)
> > +			tx = dev->device_prep_dma_sg(chan, tx_sg,
> > +					dst_cnt, rx_sg, src_cnt, flags);
> 
> again dst_cnt

Will fix in v2.

> 
> >  		else if (thread->type == DMA_XOR)
> >  			tx = dev->device_prep_dma_xor(chan,
> >  						      dsts[0] + dst_off,
> > @@ -748,6 +771,8 @@ static int dmatest_add_threads(struct dmatest_info
> > *info,
> >
> >  	if (type == DMA_MEMCPY)
> >  		op = "copy";
> > +	else if (type == DMA_SG)
> > +		op = "sg";
> >  	else if (type == DMA_XOR)
> >  		op = "xor";
> >  	else if (type == DMA_PQ)
> > @@ -802,8 +827,16 @@ static int dmatest_add_channel(struct dmatest_info
> *info,
> >  	INIT_LIST_HEAD(&dtc->threads);
> >
> >  	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
> > -		cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
> > -		thread_count += cnt > 0 ? cnt : 0;
> > +		if (dmatest == 0) {
> > +			cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
> > +			thread_count += cnt > 0 ? cnt : 0;
> > +		}
> > +	}
> 
> blank line

Ok sure will fix in v2...

Thanks,
Kedar.

> 
> --
> ~Vinod