From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id DB30921C9127D for ; Tue, 1 Aug 2017 09:37:31 -0700 (PDT) Subject: Re: [PATCH 2/5] dmaengine: ioatdma: dma_prep_memcpy_to/from_sg support References: <150153948477.49768.5767882242140065474.stgit@djiang5-desk3.ch.intel.com> <150153986963.49768.7407643931348757530.stgit@djiang5-desk3.ch.intel.com> From: Dave Jiang Message-ID: Date: Tue, 1 Aug 2017 09:39:05 -0700 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: Dan Williams Cc: "Koul, Vinod" , "dmaengine@vger.kernel.org" , "linux-nvdimm@lists.01.org" List-ID: On 07/31/2017 07:14 PM, Dan Williams wrote: > On Mon, Jul 31, 2017 at 3:24 PM, Dave Jiang wrote: >> Adding ioatdma support to copy from a physically contiguos buffer to a >> provided scatterlist and vice versa. This is used to support >> reading/writing persistent memory in the pmem driver. >> >> Signed-off-by: Dave Jiang >> --- >> drivers/dma/ioat/dma.h | 8 +++ >> drivers/dma/ioat/init.c | 3 + >> drivers/dma/ioat/prep.c | 105 +++++++++++++++++++++++++++++++++++++++++++++ >> include/linux/dmaengine.h | 10 ++++ >> 4 files changed, 126 insertions(+) >> >> diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h >> index 56200ee..b9a8d82 100644 >> --- a/drivers/dma/ioat/dma.h >> +++ b/drivers/dma/ioat/dma.h >> @@ -370,6 +370,14 @@ struct dma_async_tx_descriptor * >> ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest, >> dma_addr_t dma_src, size_t len, unsigned long flags); >> struct dma_async_tx_descriptor * >> +ioat_dma_prep_memcpy_to_sg_lock(struct dma_chan *c, >> + struct scatterlist *dst_sg, unsigned int dst_nents, >> + dma_addr_t src, unsigned long flags); >> +struct dma_async_tx_descriptor * >> +ioat_dma_prep_memcpy_from_sg_lock(struct dma_chan *c, dma_addr_t dst, >> + struct scatterlist *dst_sg, unsigned int dst_nents, >> + unsigned long flags); >> +struct dma_async_tx_descriptor * >> ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags); >> struct dma_async_tx_descriptor * >> ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src, >> diff --git a/drivers/dma/ioat/init.c b/drivers/dma/ioat/init.c >> index e437112..1e03f3e 100644 >> --- a/drivers/dma/ioat/init.c >> +++ b/drivers/dma/ioat/init.c >> @@ -1091,6 +1091,9 @@ static int ioat3_dma_probe(struct ioatdma_device *ioat_dma, int dca) >> >> dma = &ioat_dma->dma_dev; >> dma->device_prep_dma_memcpy = ioat_dma_prep_memcpy_lock; >> + dma->device_prep_dma_memcpy_to_sg = ioat_dma_prep_memcpy_to_sg_lock; >> + dma->device_prep_dma_memcpy_from_sg = >> + ioat_dma_prep_memcpy_from_sg_lock; >> dma->device_issue_pending = ioat_issue_pending; >> dma->device_alloc_chan_resources = ioat_alloc_chan_resources; >> dma->device_free_chan_resources = ioat_free_chan_resources; >> diff --git a/drivers/dma/ioat/prep.c b/drivers/dma/ioat/prep.c >> index 243421a..49e220c 100644 >> --- a/drivers/dma/ioat/prep.c >> +++ b/drivers/dma/ioat/prep.c >> @@ -159,6 +159,111 @@ ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest, >> return &desc->txd; >> } >> >> +struct dma_async_tx_descriptor * >> +ioat_dma_prep_memcpy_to_sg_lock(struct dma_chan *c, >> + struct scatterlist *dst_sg, unsigned int dst_nents, >> + dma_addr_t dma_src, unsigned long flags) >> +{ >> + struct ioatdma_chan *ioat_chan = to_ioat_chan(c); >> + struct ioat_dma_descriptor *hw = NULL; >> + struct ioat_ring_ent *desc = NULL; >> + dma_addr_t src = dma_src; >> + int num_descs, idx, i; >> + struct scatterlist *s; >> + size_t total_len = 0, len; >> + >> + >> + if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state)) >> + return NULL; >> + >> + /* >> + * The upper layer will garantee that each entry does not exceed >> + * xfercap. >> + */ >> + num_descs = dst_nents; >> + >> + if (likely(num_descs) && >> + ioat_check_space_lock(ioat_chan, num_descs) == 0) >> + idx = ioat_chan->head; >> + else >> + return NULL; >> + >> + for_each_sg(dst_sg, s, dst_nents, i) { >> + desc = ioat_get_ring_ent(ioat_chan, idx + i); >> + hw = desc->hw; >> + len = sg_dma_len(s); >> + hw->size = len; >> + hw->ctl = 0; >> + hw->src_addr = src; >> + hw->dst_addr = sg_dma_address(s); >> + src += len; >> + total_len += len; >> + dump_desc_dbg(ioat_chan, desc); >> + } >> + >> + desc->txd.flags = flags; >> + desc->len = total_len; >> + hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT); >> + hw->ctl_f.fence = !!(flags & DMA_PREP_FENCE); >> + hw->ctl_f.compl_write = 1; >> + dump_desc_dbg(ioat_chan, desc); >> + /* we leave the channel locked to ensure in order submission */ >> + >> + return &desc->txd; >> +} >> + >> +struct dma_async_tx_descriptor * >> +ioat_dma_prep_memcpy_from_sg_lock(struct dma_chan *c, dma_addr_t dma_dst, >> + struct scatterlist *src_sg, unsigned int src_nents, >> + unsigned long flags) >> +{ >> + struct ioatdma_chan *ioat_chan = to_ioat_chan(c); >> + struct ioat_dma_descriptor *hw = NULL; >> + struct ioat_ring_ent *desc = NULL; >> + dma_addr_t dst = dma_dst; >> + int num_descs, idx, i; >> + struct scatterlist *s; >> + size_t total_len = 0, len; >> + >> + >> + if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state)) >> + return NULL; >> + >> + /* >> + * The upper layer will garantee that each entry does not exceed >> + * xfercap. >> + */ >> + num_descs = src_nents; >> + >> + if (likely(num_descs) && >> + ioat_check_space_lock(ioat_chan, num_descs) == 0) >> + idx = ioat_chan->head; >> + else >> + return NULL; >> + >> + for_each_sg(src_sg, s, src_nents, i) { >> + desc = ioat_get_ring_ent(ioat_chan, idx + i); >> + hw = desc->hw; >> + len = sg_dma_len(s); >> + hw->size = len; >> + hw->ctl = 0; >> + hw->src_addr = sg_dma_address(s); >> + hw->dst_addr = dst; >> + dst += len; >> + total_len += len; >> + dump_desc_dbg(ioat_chan, desc); >> + } >> + >> + desc->txd.flags = flags; >> + desc->len = total_len; >> + hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT); >> + hw->ctl_f.fence = !!(flags & DMA_PREP_FENCE); >> + hw->ctl_f.compl_write = 1; >> + dump_desc_dbg(ioat_chan, desc); >> + /* we leave the channel locked to ensure in order submission */ >> + >> + return &desc->txd; >> +} >> >> static struct dma_async_tx_descriptor * >> __ioat_prep_xor_lock(struct dma_chan *c, enum sum_check_flags *result, >> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h >> index 5336808..6202e7c 100644 >> --- a/include/linux/dmaengine.h >> +++ b/include/linux/dmaengine.h >> @@ -694,6 +694,8 @@ struct dma_filter { >> * @device_prep_dma_memset: prepares a memset operation >> * @device_prep_dma_memset_sg: prepares a memset operation over a scatter list >> * @device_prep_dma_interrupt: prepares an end of chain interrupt operation >> + * @device_prep_dma_memcpy_to_sg: prepares memcpy from buffer to scatterlist >> + * @device_prep_dma_memcpy_from_sg: prepares memcpy from scatterlist to buffer >> * @device_prep_slave_sg: prepares a slave dma operation >> * @device_prep_dma_cyclic: prepare a cyclic dma operation suitable for audio. >> * The function takes a buffer of size buf_len. The callback function will >> @@ -776,6 +778,14 @@ struct dma_device { >> struct scatterlist *dst_sg, unsigned int dst_nents, >> struct scatterlist *src_sg, unsigned int src_nents, >> unsigned long flags); >> + struct dma_async_tx_descriptor *(*device_prep_dma_memcpy_to_sg)( >> + struct dma_chan *chan, >> + struct scatterlist *dst_sg, unsigned int dst_nents, >> + dma_addr_t src, unsigned long flags); >> + struct dma_async_tx_descriptor *(*device_prep_dma_memcpy_from_sg)( >> + struct dma_chan *chan, dma_addr_t dst, >> + struct scatterlist *dst_sg, unsigned int dst_nents, >> + unsigned long flags); >> >> struct dma_async_tx_descriptor *(*device_prep_slave_sg)( >> struct dma_chan *chan, struct scatterlist *sgl, >> > > Can we get away with just adding one new operation with a flag to > indicate whether it is the 'to' or' 'from' sg case? > Yes I can try to make that happen. _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm