Merge tag 'drivers-5.10-2020-10-12' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "Here are the driver updates for 5.10.

  A few SCSI updates in here too, in coordination with Martin as they
  depend on core block changes for the shared tag bitmap.

  This contains:

   - NVMe pull requests via Christoph:
      - fix keep alive timer modification (Amit Engel)
      - order the PCI ID list more sensibly (Andy Shevchenko)
      - cleanup the open by controller helper (Chaitanya Kulkarni)
      - use an xarray for the CSE log lookup (Chaitanya Kulkarni)
      - support ZNS in nvmet passthrough mode (Chaitanya Kulkarni)
      - fix nvme_ns_report_zones (Christoph Hellwig)
      - add a sanity check to nvmet-fc (James Smart)
      - fix interrupt allocation when too many polled queues are
        specified (Jeffle Xu)
      - small nvmet-tcp optimization (Mark Wunderlich)
      - fix a controller refcount leak on init failure (Chaitanya
        Kulkarni)
      - misc cleanups (Chaitanya Kulkarni)
      - major refactoring of the scanning code (Christoph Hellwig)

   - MD updates via Song:
      - Bug fixes in bitmap code, from Zhao Heming
      - Fix a work queue check, from Guoqing Jiang
      - Fix raid5 oops with reshape, from Song Liu
      - Clean up unused code, from Jason Yan
      - Discard improvements, from Xiao Ni
      - raid5/6 page offset support, from Yufen Yu

   - Shared tag bitmap for SCSI/hisi_sas/null_blk (John, Kashyap,
     Hannes)

   - null_blk open/active zone limit support (Niklas)

   - Set of bcache updates (Coly, Dongsheng, Qinglang)"

* tag 'drivers-5.10-2020-10-12' of git://git.kernel.dk/linux-block: (78 commits)
  md/raid5: fix oops during stripe resizing
  md/bitmap: fix memory leak of temporary bitmap
  md: fix the checking of wrong work queue
  md/bitmap: md_bitmap_get_counter returns wrong blocks
  md/bitmap: md_bitmap_read_sb uses wrong bitmap blocks
  md/raid0: remove unused function is_io_in_chunk_boundary()
  nvme-core: remove extra condition for vwc
  nvme-core: remove extra variable
  nvme: remove nvme_identify_ns_list
  nvme: refactor nvme_validate_ns
  nvme: move nvme_validate_ns
  nvme: query namespace identifiers before adding the namespace
  nvme: revalidate zone bitmaps in nvme_update_ns_info
  nvme: remove nvme_update_formats
  nvme: update the known admin effects
  nvme: set the queue limits in nvme_update_ns_info
  nvme: remove the 0 lba_shift check in nvme_update_ns_info
  nvme: clean up the check for too large logic block sizes
  nvme: freeze the queue over ->lba_shift updates
  nvme: factor out a nvme_configure_metadata helper
  ...

crypto/async_tx/async_pq.c

@@ -104,7 +104,7 @@ do_async_gen_syndrome(struct dma_chan *chan,
  * do_sync_gen_syndrome - synchronously calculate a raid6 syndrome
  */
 static void
-do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
+do_sync_gen_syndrome(struct page **blocks, unsigned int *offsets, int disks,
 		     size_t len, struct async_submit_ctl *submit)
 {
 	void **srcs;
@@ -121,7 +121,8 @@ do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
 			BUG_ON(i > disks - 3); /* P or Q can't be zero */
 			srcs[i] = (void*)raid6_empty_zero_page;
 		} else {
-			srcs[i] = page_address(blocks[i]) + offset;
+			srcs[i] = page_address(blocks[i]) + offsets[i];
+
 			if (i < disks - 2) {
 				stop = i;
 				if (start == -1)
@@ -138,10 +139,23 @@ do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
 	async_tx_sync_epilog(submit);
 }
 
+static inline bool
+is_dma_pq_aligned_offs(struct dma_device *dev, unsigned int *offs,
+				     int src_cnt, size_t len)
+{
+	int i;
+
+	for (i = 0; i < src_cnt; i++) {
+		if (!is_dma_pq_aligned(dev, offs[i], 0, len))
+			return false;
+	}
+	return true;
+}
+
 /**
  * async_gen_syndrome - asynchronously calculate a raid6 syndrome
  * @blocks: source blocks from idx 0..disks-3, P @ disks-2 and Q @ disks-1
- * @offset: common offset into each block (src and dest) to start transaction
+ * @offsets: offset array into each block (src and dest) to start transaction
  * @disks: number of blocks (including missing P or Q, see below)
  * @len: length of operation in bytes
  * @submit: submission/completion modifiers
@@ -160,7 +174,7 @@ do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
  * path.
  */
 struct dma_async_tx_descriptor *
-async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
+async_gen_syndrome(struct page **blocks, unsigned int *offsets, int disks,
 		   size_t len, struct async_submit_ctl *submit)
 {
 	int src_cnt = disks - 2;
@@ -179,7 +193,7 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
 	if (unmap && !(submit->flags & ASYNC_TX_PQ_XOR_DST) &&
 	    (src_cnt <= dma_maxpq(device, 0) ||
 	     dma_maxpq(device, DMA_PREP_CONTINUE) > 0) &&
-	    is_dma_pq_aligned(device, offset, 0, len)) {
+	    is_dma_pq_aligned_offs(device, offsets, disks, len)) {
 		struct dma_async_tx_descriptor *tx;
 		enum dma_ctrl_flags dma_flags = 0;
 		unsigned char coefs[MAX_DISKS];
@@ -196,8 +210,8 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
 		for (i = 0, j = 0; i < src_cnt; i++) {
 			if (blocks[i] == NULL)
 				continue;
-			unmap->addr[j] = dma_map_page(device->dev, blocks[i], offset,
-						      len, DMA_TO_DEVICE);
+			unmap->addr[j] = dma_map_page(device->dev, blocks[i],
+						offsets[i], len, DMA_TO_DEVICE);
 			coefs[j] = raid6_gfexp[i];
 			unmap->to_cnt++;
 			j++;
@@ -210,7 +224,8 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
 		unmap->bidi_cnt++;
 		if (P(blocks, disks))
 			unmap->addr[j++] = dma_map_page(device->dev, P(blocks, disks),
-							offset, len, DMA_BIDIRECTIONAL);
+							P(offsets, disks),
+							len, DMA_BIDIRECTIONAL);
 		else {
 			unmap->addr[j++] = 0;
 			dma_flags |= DMA_PREP_PQ_DISABLE_P;
@@ -219,7 +234,8 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
 		unmap->bidi_cnt++;
 		if (Q(blocks, disks))
 			unmap->addr[j++] = dma_map_page(device->dev, Q(blocks, disks),
-						       offset, len, DMA_BIDIRECTIONAL);
+							Q(offsets, disks),
+							len, DMA_BIDIRECTIONAL);
 		else {
 			unmap->addr[j++] = 0;
 			dma_flags |= DMA_PREP_PQ_DISABLE_Q;
@@ -240,13 +256,13 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
 
 	if (!P(blocks, disks)) {
 		P(blocks, disks) = pq_scribble_page;
-		BUG_ON(len + offset > PAGE_SIZE);
+		P(offsets, disks) = 0;
 	}
 	if (!Q(blocks, disks)) {
 		Q(blocks, disks) = pq_scribble_page;
-		BUG_ON(len + offset > PAGE_SIZE);
+		Q(offsets, disks) = 0;
 	}
-	do_sync_gen_syndrome(blocks, offset, disks, len, submit);
+	do_sync_gen_syndrome(blocks, offsets, disks, len, submit);
 
 	return NULL;
 }
@@ -270,6 +286,7 @@ pq_val_chan(struct async_submit_ctl *submit, struct page **blocks, int disks, si
  * @len: length of operation in bytes
  * @pqres: on val failure SUM_CHECK_P_RESULT and/or SUM_CHECK_Q_RESULT are set
  * @spare: temporary result buffer for the synchronous case
+ * @s_off: spare buffer page offset
  * @submit: submission / completion modifiers
  *
  * The same notes from async_gen_syndrome apply to the 'blocks',
@@ -278,9 +295,9 @@ pq_val_chan(struct async_submit_ctl *submit, struct page **blocks, int disks, si
  * specified.
  */
 struct dma_async_tx_descriptor *
-async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
+async_syndrome_val(struct page **blocks, unsigned int *offsets, int disks,
 		   size_t len, enum sum_check_flags *pqres, struct page *spare,
-		   struct async_submit_ctl *submit)
+		   unsigned int s_off, struct async_submit_ctl *submit)
 {
 	struct dma_chan *chan = pq_val_chan(submit, blocks, disks, len);
 	struct dma_device *device = chan ? chan->device : NULL;
@@ -295,7 +312,7 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
 		unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOWAIT);
 
 	if (unmap && disks <= dma_maxpq(device, 0) &&
-	    is_dma_pq_aligned(device, offset, 0, len)) {
+	    is_dma_pq_aligned_offs(device, offsets, disks, len)) {
 		struct device *dev = device->dev;
 		dma_addr_t pq[2];
 		int i, j = 0, src_cnt = 0;
@@ -307,7 +324,7 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
 		for (i = 0; i < disks-2; i++)
 			if (likely(blocks[i])) {
 				unmap->addr[j] = dma_map_page(dev, blocks[i],
-							      offset, len,
+							      offsets[i], len,
 							      DMA_TO_DEVICE);
 				coefs[j] = raid6_gfexp[i];
 				unmap->to_cnt++;
@@ -320,7 +337,7 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
 			dma_flags |= DMA_PREP_PQ_DISABLE_P;
 		} else {
 			pq[0] = dma_map_page(dev, P(blocks, disks),
-					     offset, len,
+					     P(offsets, disks), len,
 					     DMA_TO_DEVICE);
 			unmap->addr[j++] = pq[0];
 			unmap->to_cnt++;
@@ -330,7 +347,7 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
 			dma_flags |= DMA_PREP_PQ_DISABLE_Q;
 		} else {
 			pq[1] = dma_map_page(dev, Q(blocks, disks),
-					     offset, len,
+					     Q(offsets, disks), len,
 					     DMA_TO_DEVICE);
 			unmap->addr[j++] = pq[1];
 			unmap->to_cnt++;
@@ -355,7 +372,9 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
 		async_tx_submit(chan, tx, submit);
 	} else {
 		struct page *p_src = P(blocks, disks);
+		unsigned int p_off = P(offsets, disks);
 		struct page *q_src = Q(blocks, disks);
+		unsigned int q_off = Q(offsets, disks);
 		enum async_tx_flags flags_orig = submit->flags;
 		dma_async_tx_callback cb_fn_orig = submit->cb_fn;
 		void *scribble = submit->scribble;
@@ -381,27 +400,32 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
 		if (p_src) {
 			init_async_submit(submit, ASYNC_TX_XOR_ZERO_DST, NULL,
 					  NULL, NULL, scribble);
-			tx = async_xor(spare, blocks, offset, disks-2, len, submit);
+			tx = async_xor_offs(spare, s_off,
+					blocks, offsets, disks-2, len, submit);
 			async_tx_quiesce(&tx);
-			p = page_address(p_src) + offset;
-			s = page_address(spare) + offset;
+			p = page_address(p_src) + p_off;
+			s = page_address(spare) + s_off;
 			*pqres |= !!memcmp(p, s, len) << SUM_CHECK_P;
 		}
 
 		if (q_src) {
 			P(blocks, disks) = NULL;
 			Q(blocks, disks) = spare;
+			Q(offsets, disks) = s_off;
 			init_async_submit(submit, 0, NULL, NULL, NULL, scribble);
-			tx = async_gen_syndrome(blocks, offset, disks, len, submit);
+			tx = async_gen_syndrome(blocks, offsets, disks,
+					len, submit);
 			async_tx_quiesce(&tx);
-			q = page_address(q_src) + offset;
-			s = page_address(spare) + offset;
+			q = page_address(q_src) + q_off;
+			s = page_address(spare) + s_off;
 			*pqres |= !!memcmp(q, s, len) << SUM_CHECK_Q;
 		}
 
 		/* restore P, Q and submit */
 		P(blocks, disks) = p_src;
+		P(offsets, disks) = p_off;
 		Q(blocks, disks) = q_src;
+		Q(offsets, disks) = q_off;
 
 		submit->cb_fn = cb_fn_orig;
 		submit->cb_param = cb_param_orig;

crypto/async_tx/async_raid6_recov.c

@@ -15,8 +15,9 @@
 #include <linux/dmaengine.h>
 
 static struct dma_async_tx_descriptor *
-async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef,
-		  size_t len, struct async_submit_ctl *submit)
+async_sum_product(struct page *dest, unsigned int d_off,
+		struct page **srcs, unsigned int *src_offs, unsigned char *coef,
+		size_t len, struct async_submit_ctl *submit)
 {
 	struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ,
 						      &dest, 1, srcs, 2, len);
@@ -37,11 +38,14 @@ async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef,
 
 		if (submit->flags & ASYNC_TX_FENCE)
 			dma_flags |= DMA_PREP_FENCE;
-		unmap->addr[0] = dma_map_page(dev, srcs[0], 0, len, DMA_TO_DEVICE);
-		unmap->addr[1] = dma_map_page(dev, srcs[1], 0, len, DMA_TO_DEVICE);
+		unmap->addr[0] = dma_map_page(dev, srcs[0], src_offs[0],
+						len, DMA_TO_DEVICE);
+		unmap->addr[1] = dma_map_page(dev, srcs[1], src_offs[1],
+						len, DMA_TO_DEVICE);
 		unmap->to_cnt = 2;
 
-		unmap->addr[2] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
+		unmap->addr[2] = dma_map_page(dev, dest, d_off,
+						len, DMA_BIDIRECTIONAL);
 		unmap->bidi_cnt = 1;
 		/* engine only looks at Q, but expects it to follow P */
 		pq[1] = unmap->addr[2];
@@ -66,9 +70,9 @@ async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef,
 	async_tx_quiesce(&submit->depend_tx);
 	amul = raid6_gfmul[coef[0]];
 	bmul = raid6_gfmul[coef[1]];
-	a = page_address(srcs[0]);
-	b = page_address(srcs[1]);
-	c = page_address(dest);
+	a = page_address(srcs[0]) + src_offs[0];
+	b = page_address(srcs[1]) + src_offs[1];
+	c = page_address(dest) + d_off;
 
 	while (len--) {
 		ax    = amul[*a++];
@@ -80,8 +84,9 @@ async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef,
 }
 
 static struct dma_async_tx_descriptor *
-async_mult(struct page *dest, struct page *src, u8 coef, size_t len,
-	   struct async_submit_ctl *submit)
+async_mult(struct page *dest, unsigned int d_off, struct page *src,
+		unsigned int s_off, u8 coef, size_t len,
+		struct async_submit_ctl *submit)
 {
 	struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ,
 						      &dest, 1, &src, 1, len);
@@ -101,9 +106,11 @@ async_mult(struct page *dest, struct page *src, u8 coef, size_t len,
 
 		if (submit->flags & ASYNC_TX_FENCE)
 			dma_flags |= DMA_PREP_FENCE;
-		unmap->addr[0] = dma_map_page(dev, src, 0, len, DMA_TO_DEVICE);
+		unmap->addr[0] = dma_map_page(dev, src, s_off,
+						len, DMA_TO_DEVICE);
 		unmap->to_cnt++;
-		unmap->addr[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
+		unmap->addr[1] = dma_map_page(dev, dest, d_off,
+						len, DMA_BIDIRECTIONAL);
 		dma_dest[1] = unmap->addr[1];
 		unmap->bidi_cnt++;
 		unmap->len = len;
@@ -133,8 +140,8 @@ async_mult(struct page *dest, struct page *src, u8 coef, size_t len,
 	 */
 	async_tx_quiesce(&submit->depend_tx);
 	qmul  = raid6_gfmul[coef];
-	d = page_address(dest);
-	s = page_address(src);
+	d = page_address(dest) + d_off;
+	s = page_address(src) + s_off;
 
 	while (len--)
 		*d++ = qmul[*s++];
@@ -144,11 +151,14 @@ async_mult(struct page *dest, struct page *src, u8 coef, size_t len,
 
 static struct dma_async_tx_descriptor *
 __2data_recov_4(int disks, size_t bytes, int faila, int failb,
-		struct page **blocks, struct async_submit_ctl *submit)
+		struct page **blocks, unsigned int *offs,
+		struct async_submit_ctl *submit)
 {
 	struct dma_async_tx_descriptor *tx = NULL;
 	struct page *p, *q, *a, *b;
+	unsigned int p_off, q_off, a_off, b_off;
 	struct page *srcs[2];
+	unsigned int src_offs[2];
 	unsigned char coef[2];
 	enum async_tx_flags flags = submit->flags;
 	dma_async_tx_callback cb_fn = submit->cb_fn;
@@ -156,26 +166,34 @@ __2data_recov_4(int disks, size_t bytes, int faila, int failb,
 	void *scribble = submit->scribble;
 
 	p = blocks[disks-2];
+	p_off = offs[disks-2];
 	q = blocks[disks-1];
+	q_off = offs[disks-1];
 
 	a = blocks[faila];
+	a_off = offs[faila];
 	b = blocks[failb];
+	b_off = offs[failb];
 
 	/* in the 4 disk case P + Pxy == P and Q + Qxy == Q */
 	/* Dx = A*(P+Pxy) + B*(Q+Qxy) */
 	srcs[0] = p;
+	src_offs[0] = p_off;
 	srcs[1] = q;
+	src_offs[1] = q_off;
 	coef[0] = raid6_gfexi[failb-faila];
 	coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]];
 	init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
-	tx = async_sum_product(b, srcs, coef, bytes, submit);
+	tx = async_sum_product(b, b_off, srcs, src_offs, coef, bytes, submit);
 
 	/* Dy = P+Pxy+Dx */
 	srcs[0] = p;
+	src_offs[0] = p_off;
 	srcs[1] = b;
+	src_offs[1] = b_off;
 	init_async_submit(submit, flags | ASYNC_TX_XOR_ZERO_DST, tx, cb_fn,
 			  cb_param, scribble);
-	tx = async_xor(a, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(a, a_off, srcs, src_offs, 2, bytes, submit);
 
 	return tx;
 
@@ -183,11 +201,14 @@ __2data_recov_4(int disks, size_t bytes, int faila, int failb,
 
 static struct dma_async_tx_descriptor *
 __2data_recov_5(int disks, size_t bytes, int faila, int failb,
-		struct page **blocks, struct async_submit_ctl *submit)
+		struct page **blocks, unsigned int *offs,
+		struct async_submit_ctl *submit)
 {
 	struct dma_async_tx_descriptor *tx = NULL;
 	struct page *p, *q, *g, *dp, *dq;
+	unsigned int p_off, q_off, g_off, dp_off, dq_off;
 	struct page *srcs[2];
+	unsigned int src_offs[2];
 	unsigned char coef[2];
 	enum async_tx_flags flags = submit->flags;
 	dma_async_tx_callback cb_fn = submit->cb_fn;
@@ -208,60 +229,77 @@ __2data_recov_5(int disks, size_t bytes, int faila, int failb,
 	BUG_ON(good_srcs > 1);
 
 	p = blocks[disks-2];
+	p_off = offs[disks-2];
 	q = blocks[disks-1];
+	q_off = offs[disks-1];
 	g = blocks[good];
+	g_off = offs[good];
 
 	/* Compute syndrome with zero for the missing data pages
 	 * Use the dead data pages as temporary storage for delta p and
 	 * delta q
 	 */
 	dp = blocks[faila];
+	dp_off = offs[faila];
 	dq = blocks[failb];
+	dq_off = offs[failb];
 
 	init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
-	tx = async_memcpy(dp, g, 0, 0, bytes, submit);
+	tx = async_memcpy(dp, g, dp_off, g_off, bytes, submit);
 	init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
-	tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit);
+	tx = async_mult(dq, dq_off, g, g_off,
+			raid6_gfexp[good], bytes, submit);
 
 	/* compute P + Pxy */
 	srcs[0] = dp;
+	src_offs[0] = dp_off;
 	srcs[1] = p;
+	src_offs[1] = p_off;
 	init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
 			  NULL, NULL, scribble);
-	tx = async_xor(dp, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(dp, dp_off, srcs, src_offs, 2, bytes, submit);
 
 	/* compute Q + Qxy */
 	srcs[0] = dq;
+	src_offs[0] = dq_off;
 	srcs[1] = q;
+	src_offs[1] = q_off;
 	init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
 			  NULL, NULL, scribble);
-	tx = async_xor(dq, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(dq, dq_off, srcs, src_offs, 2, bytes, submit);
 
 	/* Dx = A*(P+Pxy) + B*(Q+Qxy) */
 	srcs[0] = dp;
+	src_offs[0] = dp_off;
 	srcs[1] = dq;
+	src_offs[1] = dq_off;
 	coef[0] = raid6_gfexi[failb-faila];
 	coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]];
 	init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
-	tx = async_sum_product(dq, srcs, coef, bytes, submit);
+	tx = async_sum_product(dq, dq_off, srcs, src_offs, coef, bytes, submit);
 
 	/* Dy = P+Pxy+Dx */
 	srcs[0] = dp;
+	src_offs[0] = dp_off;
 	srcs[1] = dq;
+	src_offs[1] = dq_off;
 	init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn,
 			  cb_param, scribble);
-	tx = async_xor(dp, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(dp, dp_off, srcs, src_offs, 2, bytes, submit);
 
 	return tx;
 }
 
 static struct dma_async_tx_descriptor *
 __2data_recov_n(int disks, size_t bytes, int faila, int failb,
-	      struct page **blocks, struct async_submit_ctl *submit)
+	      struct page **blocks, unsigned int *offs,
+		  struct async_submit_ctl *submit)
 {
 	struct dma_async_tx_descriptor *tx = NULL;
 	struct page *p, *q, *dp, *dq;
+	unsigned int p_off, q_off, dp_off, dq_off;
 	struct page *srcs[2];
+	unsigned int src_offs[2];
 	unsigned char coef[2];
 	enum async_tx_flags flags = submit->flags;
 	dma_async_tx_callback cb_fn = submit->cb_fn;
@@ -269,56 +307,74 @@ __2data_recov_n(int disks, size_t bytes, int faila, int failb,
 	void *scribble = submit->scribble;
 
 	p = blocks[disks-2];
+	p_off = offs[disks-2];
 	q = blocks[disks-1];
+	q_off = offs[disks-1];
 
 	/* Compute syndrome with zero for the missing data pages
 	 * Use the dead data pages as temporary storage for
 	 * delta p and delta q
 	 */
 	dp = blocks[faila];
+	dp_off = offs[faila];
 	blocks[faila] = NULL;
 	blocks[disks-2] = dp;
+	offs[disks-2] = dp_off;
 	dq = blocks[failb];
+	dq_off = offs[failb];
 	blocks[failb] = NULL;
 	blocks[disks-1] = dq;
+	offs[disks-1] = dq_off;
 
 	init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
-	tx = async_gen_syndrome(blocks, 0, disks, bytes, submit);
+	tx = async_gen_syndrome(blocks, offs, disks, bytes, submit);
 
 	/* Restore pointer table */
 	blocks[faila]   = dp;
+	offs[faila] = dp_off;
 	blocks[failb]   = dq;
+	offs[failb] = dq_off;
 	blocks[disks-2] = p;
+	offs[disks-2] = p_off;
 	blocks[disks-1] = q;
+	offs[disks-1] = q_off;
 
 	/* compute P + Pxy */
 	srcs[0] = dp;
+	src_offs[0] = dp_off;
 	srcs[1] = p;
+	src_offs[1] = p_off;
 	init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
 			  NULL, NULL, scribble);
-	tx = async_xor(dp, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(dp, dp_off, srcs, src_offs, 2, bytes, submit);
 
 	/* compute Q + Qxy */
 	srcs[0] = dq;
+	src_offs[0] = dq_off;
 	srcs[1] = q;
+	src_offs[1] = q_off;
 	init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
 			  NULL, NULL, scribble);
-	tx = async_xor(dq, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(dq, dq_off, srcs, src_offs, 2, bytes, submit);
 
 	/* Dx = A*(P+Pxy) + B*(Q+Qxy) */
 	srcs[0] = dp;
+	src_offs[0] = dp_off;
 	srcs[1] = dq;
+	src_offs[1] = dq_off;
 	coef[0] = raid6_gfexi[failb-faila];
 	coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]];
 	init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
-	tx = async_sum_product(dq, srcs, coef, bytes, submit);
+	tx = async_sum_product(dq, dq_off, srcs, src_offs, coef, bytes, submit);
 
 	/* Dy = P+Pxy+Dx */
 	srcs[0] = dp;
+	src_offs[0] = dp_off;
 	srcs[1] = dq;
+	src_offs[1] = dq_off;
 	init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn,
 			  cb_param, scribble);
-	tx = async_xor(dp, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(dp, dp_off, srcs, src_offs, 2, bytes, submit);
 
 	return tx;
 }
@@ -330,11 +386,13 @@ __2data_recov_n(int disks, size_t bytes, int faila, int failb,
  * @faila: first failed drive index
  * @failb: second failed drive index
  * @blocks: array of source pointers where the last two entries are p and q
+ * @offs: array of offset for pages in blocks
  * @submit: submission/completion modifiers
  */
 struct dma_async_tx_descriptor *
 async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
-			struct page **blocks, struct async_submit_ctl *submit)
+			struct page **blocks, unsigned int *offs,
+			struct async_submit_ctl *submit)
 {
 	void *scribble = submit->scribble;
 	int non_zero_srcs, i;
@@ -358,7 +416,7 @@ async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
 			if (blocks[i] == NULL)
 				ptrs[i] = (void *) raid6_empty_zero_page;
 			else
-				ptrs[i] = page_address(blocks[i]);
+				ptrs[i] = page_address(blocks[i]) + offs[i];
 
 		raid6_2data_recov(disks, bytes, faila, failb, ptrs);
 
@@ -383,16 +441,19 @@ async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
 		 * explicitly handle the special case of a 4 disk array with
 		 * both data disks missing.
 		 */
-		return __2data_recov_4(disks, bytes, faila, failb, blocks, submit);
+		return __2data_recov_4(disks, bytes, faila, failb,
+				blocks, offs, submit);
 	case 3:
 		/* dma devices do not uniformly understand a single
 		 * source pq operation (in contrast to the synchronous
 		 * case), so explicitly handle the special case of a 5 disk
 		 * array with 2 of 3 data disks missing.
 		 */
-		return __2data_recov_5(disks, bytes, faila, failb, blocks, submit);
+		return __2data_recov_5(disks, bytes, faila, failb,
+				blocks, offs, submit);
 	default:
-		return __2data_recov_n(disks, bytes, faila, failb, blocks, submit);
+		return __2data_recov_n(disks, bytes, faila, failb,
+				blocks, offs, submit);
 	}
 }
 EXPORT_SYMBOL_GPL(async_raid6_2data_recov);
@@ -403,14 +464,17 @@ EXPORT_SYMBOL_GPL(async_raid6_2data_recov);
  * @bytes: block size
  * @faila: failed drive index
  * @blocks: array of source pointers where the last two entries are p and q
+ * @offs: array of offset for pages in blocks
  * @submit: submission/completion modifiers
  */
 struct dma_async_tx_descriptor *
 async_raid6_datap_recov(int disks, size_t bytes, int faila,
-			struct page **blocks, struct async_submit_ctl *submit)
+			struct page **blocks, unsigned int *offs,
+			struct async_submit_ctl *submit)
 {
 	struct dma_async_tx_descriptor *tx = NULL;
 	struct page *p, *q, *dq;
+	unsigned int p_off, q_off, dq_off;
 	u8 coef;
 	enum async_tx_flags flags = submit->flags;
 	dma_async_tx_callback cb_fn = submit->cb_fn;
@@ -418,6 +482,7 @@ async_raid6_datap_recov(int disks, size_t bytes, int faila,
 	void *scribble = submit->scribble;
 	int good_srcs, good, i;
 	struct page *srcs[2];
+	unsigned int src_offs[2];
 
 	pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes);
 
@@ -434,7 +499,7 @@ async_raid6_datap_recov(int disks, size_t bytes, int faila,
 			if (blocks[i] == NULL)
 				ptrs[i] = (void*)raid6_empty_zero_page;
 			else
-				ptrs[i] = page_address(blocks[i]);
+				ptrs[i] = page_address(blocks[i]) + offs[i];
 
 		raid6_datap_recov(disks, bytes, faila, ptrs);
 
@@ -458,55 +523,67 @@ async_raid6_datap_recov(int disks, size_t bytes, int faila,
 	BUG_ON(good_srcs == 0);
 
 	p = blocks[disks-2];
+	p_off = offs[disks-2];
 	q = blocks[disks-1];
+	q_off = offs[disks-1];
 
 	/* Compute syndrome with zero for the missing data page
 	 * Use the dead data page as temporary storage for delta q
 	 */
 	dq = blocks[faila];
+	dq_off = offs[faila];
 	blocks[faila] = NULL;
 	blocks[disks-1] = dq;
+	offs[disks-1] = dq_off;
 
 	/* in the 4-disk case we only need to perform a single source
 	 * multiplication with the one good data block.
 	 */
 	if (good_srcs == 1) {
 		struct page *g = blocks[good];
+		unsigned int g_off = offs[good];
 
 		init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL,
 				  scribble);
-		tx = async_memcpy(p, g, 0, 0, bytes, submit);
+		tx = async_memcpy(p, g, p_off, g_off, bytes, submit);
 
 		init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL,
 				  scribble);
-		tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit);
+		tx = async_mult(dq, dq_off, g, g_off,
+				raid6_gfexp[good], bytes, submit);
 	} else {
 		init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL,
 				  scribble);
-		tx = async_gen_syndrome(blocks, 0, disks, bytes, submit);
+		tx = async_gen_syndrome(blocks, offs, disks, bytes, submit);
 	}
 
 	/* Restore pointer table */
 	blocks[faila]   = dq;
+	offs[faila] = dq_off;
 	blocks[disks-1] = q;
+	offs[disks-1] = q_off;
 
 	/* calculate g^{-faila} */
 	coef = raid6_gfinv[raid6_gfexp[faila]];
 
 	srcs[0] = dq;
+	src_offs[0] = dq_off;
 	srcs[1] = q;
+	src_offs[1] = q_off;
 	init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
 			  NULL, NULL, scribble);
-	tx = async_xor(dq, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(dq, dq_off, srcs, src_offs, 2, bytes, submit);
 
 	init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
-	tx = async_mult(dq, dq, coef, bytes, submit);
+	tx = async_mult(dq, dq_off, dq, dq_off, coef, bytes, submit);
 
 	srcs[0] = p;
+	src_offs[0] = p_off;
 	srcs[1] = dq;
+	src_offs[1] = dq_off;
 	init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn,
 			  cb_param, scribble);
-	tx = async_xor(p, srcs, 0, 2, bytes, submit);
+	tx = async_xor_offs(p, p_off, srcs, src_offs, 2, bytes, submit);
 
 	return tx;
 }

crypto/async_tx/async_xor.c

@@ -97,7 +97,8 @@ do_async_xor(struct dma_chan *chan, struct dmaengine_unmap_data *unmap,
 }
 
 static void
-do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
+do_sync_xor_offs(struct page *dest, unsigned int offset,
+		struct page **src_list, unsigned int *src_offs,
 	    int src_cnt, size_t len, struct async_submit_ctl *submit)
 {
 	int i;
@@ -114,7 +115,8 @@ do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
 	/* convert to buffer pointers */
 	for (i = 0; i < src_cnt; i++)
 		if (src_list[i])
-			srcs[xor_src_cnt++] = page_address(src_list[i]) + offset;
+			srcs[xor_src_cnt++] = page_address(src_list[i]) +
+				(src_offs ? src_offs[i] : offset);
 	src_cnt = xor_src_cnt;
 	/* set destination address */
 	dest_buf = page_address(dest) + offset;
@@ -135,11 +137,31 @@ do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
 	async_tx_sync_epilog(submit);
 }
 
+static inline bool
+dma_xor_aligned_offsets(struct dma_device *device, unsigned int offset,
+		unsigned int *src_offs, int src_cnt, int len)
+{
+	int i;
+
+	if (!is_dma_xor_aligned(device, offset, 0, len))
+		return false;
+
+	if (!src_offs)
+		return true;
+
+	for (i = 0; i < src_cnt; i++) {
+		if (!is_dma_xor_aligned(device, src_offs[i], 0, len))
+			return false;
+	}
+	return true;
+}
+
 /**
- * async_xor - attempt to xor a set of blocks with a dma engine.
+ * async_xor_offs - attempt to xor a set of blocks with a dma engine.
  * @dest: destination page
+ * @offset: dst offset to start transaction
  * @src_list: array of source pages
- * @offset: common src/dst offset to start transaction
+ * @src_offs: array of source pages offset, NULL means common src/dst offset
  * @src_cnt: number of source pages
  * @len: length in bytes
  * @submit: submission / completion modifiers
@@ -157,8 +179,9 @@ do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
  * is not specified.
  */
 struct dma_async_tx_descriptor *
-async_xor(struct page *dest, struct page **src_list, unsigned int offset,
-	  int src_cnt, size_t len, struct async_submit_ctl *submit)
+async_xor_offs(struct page *dest, unsigned int offset,
+		struct page **src_list, unsigned int *src_offs,
+		int src_cnt, size_t len, struct async_submit_ctl *submit)
 {
 	struct dma_chan *chan = async_tx_find_channel(submit, DMA_XOR,
 						      &dest, 1, src_list,
@@ -171,7 +194,8 @@ async_xor(struct page *dest, struct page **src_list, unsigned int offset,
 	if (device)
 		unmap = dmaengine_get_unmap_data(device->dev, src_cnt+1, GFP_NOWAIT);
 
-	if (unmap && is_dma_xor_aligned(device, offset, 0, len)) {
+	if (unmap && dma_xor_aligned_offsets(device, offset,
+				src_offs, src_cnt, len)) {
 		struct dma_async_tx_descriptor *tx;
 		int i, j;
 
@@ -184,7 +208,8 @@ async_xor(struct page *dest, struct page **src_list, unsigned int offset,
 				continue;
 			unmap->to_cnt++;
 			unmap->addr[j++] = dma_map_page(device->dev, src_list[i],
-							offset, len, DMA_TO_DEVICE);
+					src_offs ? src_offs[i] : offset,
+					len, DMA_TO_DEVICE);
 		}
 
 		/* map it bidirectional as it may be re-used as a source */
@@ -213,11 +238,42 @@ async_xor(struct page *dest, struct page **src_list, unsigned int offset,
 		/* wait for any prerequisite operations */
 		async_tx_quiesce(&submit->depend_tx);
 
-		do_sync_xor(dest, src_list, offset, src_cnt, len, submit);
+		do_sync_xor_offs(dest, offset, src_list, src_offs,
+				src_cnt, len, submit);
 
 		return NULL;
 	}
 }
+EXPORT_SYMBOL_GPL(async_xor_offs);
+
+/**
+ * async_xor - attempt to xor a set of blocks with a dma engine.
+ * @dest: destination page
+ * @src_list: array of source pages
+ * @offset: common src/dst offset to start transaction
+ * @src_cnt: number of source pages
+ * @len: length in bytes
+ * @submit: submission / completion modifiers
+ *
+ * honored flags: ASYNC_TX_ACK, ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DST
+ *
+ * xor_blocks always uses the dest as a source so the
+ * ASYNC_TX_XOR_ZERO_DST flag must be set to not include dest data in
+ * the calculation.  The assumption with dma eninges is that they only
+ * use the destination buffer as a source when it is explicity specified
+ * in the source list.
+ *
+ * src_list note: if the dest is also a source it must be at index zero.
+ * The contents of this array will be overwritten if a scribble region
+ * is not specified.
+ */
+struct dma_async_tx_descriptor *
+async_xor(struct page *dest, struct page **src_list, unsigned int offset,
+	  int src_cnt, size_t len, struct async_submit_ctl *submit)
+{
+	return async_xor_offs(dest, offset, src_list, NULL,
+			src_cnt, len, submit);
+}
 EXPORT_SYMBOL_GPL(async_xor);
 
 static int page_is_zero(struct page *p, unsigned int offset, size_t len)
@@ -237,10 +293,11 @@ xor_val_chan(struct async_submit_ctl *submit, struct page *dest,
 }
 
 /**
- * async_xor_val - attempt a xor parity check with a dma engine.
+ * async_xor_val_offs - attempt a xor parity check with a dma engine.
  * @dest: destination page used if the xor is performed synchronously
+ * @offset: des offset in pages to start transaction
  * @src_list: array of source pages
- * @offset: offset in pages to start transaction
+ * @src_offs: array of source pages offset, NULL means common src/det offset
  * @src_cnt: number of source pages
  * @len: length in bytes
  * @result: 0 if sum == 0 else non-zero
@@ -253,9 +310,10 @@ xor_val_chan(struct async_submit_ctl *submit, struct page *dest,
  * is not specified.
  */
 struct dma_async_tx_descriptor *
-async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
-	      int src_cnt, size_t len, enum sum_check_flags *result,
-	      struct async_submit_ctl *submit)
+async_xor_val_offs(struct page *dest, unsigned int offset,
+		struct page **src_list, unsigned int *src_offs,
+		int src_cnt, size_t len, enum sum_check_flags *result,
+		struct async_submit_ctl *submit)
 {
 	struct dma_chan *chan = xor_val_chan(submit, dest, src_list, src_cnt, len);
 	struct dma_device *device = chan ? chan->device : NULL;
@@ -268,7 +326,7 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
 		unmap = dmaengine_get_unmap_data(device->dev, src_cnt, GFP_NOWAIT);
 
 	if (unmap && src_cnt <= device->max_xor &&
-	    is_dma_xor_aligned(device, offset, 0, len)) {
+	    dma_xor_aligned_offsets(device, offset, src_offs, src_cnt, len)) {
 		unsigned long dma_prep_flags = 0;
 		int i;
 
@@ -281,7 +339,8 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
 
 		for (i = 0; i < src_cnt; i++) {
 			unmap->addr[i] = dma_map_page(device->dev, src_list[i],
-						      offset, len, DMA_TO_DEVICE);
+					src_offs ? src_offs[i] : offset,
+					len, DMA_TO_DEVICE);
 			unmap->to_cnt++;
 		}
 		unmap->len = len;
@@ -312,7 +371,8 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
 		submit->flags |= ASYNC_TX_XOR_DROP_DST;
 		submit->flags &= ~ASYNC_TX_ACK;
 
-		tx = async_xor(dest, src_list, offset, src_cnt, len, submit);
+		tx = async_xor_offs(dest, offset, src_list, src_offs,
+				src_cnt, len, submit);
 
 		async_tx_quiesce(&tx);
 
@@ -325,6 +385,32 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
 
 	return tx;
 }
+EXPORT_SYMBOL_GPL(async_xor_val_offs);
+
+/**
+ * async_xor_val - attempt a xor parity check with a dma engine.
+ * @dest: destination page used if the xor is performed synchronously
+ * @src_list: array of source pages
+ * @offset: offset in pages to start transaction
+ * @src_cnt: number of source pages
+ * @len: length in bytes
+ * @result: 0 if sum == 0 else non-zero
+ * @submit: submission / completion modifiers
+ *
+ * honored flags: ASYNC_TX_ACK
+ *
+ * src_list note: if the dest is also a source it must be at index zero.
+ * The contents of this array will be overwritten if a scribble region
+ * is not specified.
+ */
+struct dma_async_tx_descriptor *
+async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
+	      int src_cnt, size_t len, enum sum_check_flags *result,
+	      struct async_submit_ctl *submit)
+{
+	return async_xor_val_offs(dest, offset, src_list, NULL, src_cnt,
+			len, result, submit);
+}
 EXPORT_SYMBOL_GPL(async_xor_val);
 
 MODULE_AUTHOR("Intel Corporation");

crypto/async_tx/raid6test.c

@@ -18,6 +18,7 @@
 #define NDISKS 64 /* Including P and Q */
 
 static struct page *dataptrs[NDISKS];
+unsigned int dataoffs[NDISKS];
 static addr_conv_t addr_conv[NDISKS];
 static struct page *data[NDISKS+3];
 static struct page *spare;
@@ -38,6 +39,7 @@ static void makedata(int disks)
 	for (i = 0; i < disks; i++) {
 		prandom_bytes(page_address(data[i]), PAGE_SIZE);
 		dataptrs[i] = data[i];
+		dataoffs[i] = 0;
 	}
 }
 
@@ -52,7 +54,8 @@ static char disk_type(int d, int disks)
 }
 
 /* Recover two failed blocks. */
-static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, struct page **ptrs)
+static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb,
+		struct page **ptrs, unsigned int *offs)
 {
 	struct async_submit_ctl submit;
 	struct completion cmp;
@@ -66,7 +69,8 @@ static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, stru
 		if (faila == disks-2) {
 			/* P+Q failure.  Just rebuild the syndrome. */
 			init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
-			tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
+			tx = async_gen_syndrome(ptrs, offs,
+					disks, bytes, &submit);
 		} else {
 			struct page *blocks[NDISKS];
 			struct page *dest;
@@ -89,22 +93,26 @@ static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, stru
 			tx = async_xor(dest, blocks, 0, count, bytes, &submit);
 
 			init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv);
-			tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
+			tx = async_gen_syndrome(ptrs, offs,
+					disks, bytes, &submit);
 		}
 	} else {
 		if (failb == disks-2) {
 			/* data+P failure. */
 			init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
-			tx = async_raid6_datap_recov(disks, bytes, faila, ptrs, &submit);
+			tx = async_raid6_datap_recov(disks, bytes,
+					faila, ptrs, offs, &submit);
 		} else {
 			/* data+data failure. */
 			init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
-			tx = async_raid6_2data_recov(disks, bytes, faila, failb, ptrs, &submit);
+			tx = async_raid6_2data_recov(disks, bytes,
+					faila, failb, ptrs, offs, &submit);
 		}
 	}
 	init_completion(&cmp);
 	init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv);
-	tx = async_syndrome_val(ptrs, 0, disks, bytes, &result, spare, &submit);
+	tx = async_syndrome_val(ptrs, offs,
+			disks, bytes, &result, spare, 0, &submit);
 	async_tx_issue_pending(tx);
 
 	if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0)
@@ -126,7 +134,7 @@ static int test_disks(int i, int j, int disks)
 	dataptrs[i] = recovi;
 	dataptrs[j] = recovj;
 
-	raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs);
+	raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs, dataoffs);
 
 	erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE);
 	errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE);
@@ -162,7 +170,7 @@ static int test(int disks, int *tests)
 	/* Generate assumed good syndrome */
 	init_completion(&cmp);
 	init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv);
-	tx = async_gen_syndrome(dataptrs, 0, disks, PAGE_SIZE, &submit);
+	tx = async_gen_syndrome(dataptrs, dataoffs, disks, PAGE_SIZE, &submit);
 	async_tx_issue_pending(tx);
 
 	if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) {