[PATCH v2 06/13] async_xor: convert to dmaengine_unmap_data

From: Dan Williams
Date: Tue Oct 22 2013 - 17:10:16 EST


Use the generic unmap object to unmap dma buffers.

Later we can push this unmap object up to the raid layer and get rid of
the 'scribble' parameter.

Cc: Vinod Koul <vinod.koul@xxxxxxxxx>
Cc: Tomasz Figa <t.figa@xxxxxxxxxxx>
Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
[bzolnier: minor cleanups]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
---

Resend to:
1/ add it to the new dmaengine patchwork
2/ cc maintainers of affected drivers
3/ fixup some mail addresses

crypto/async_tx/async_xor.c | 95 +++++++++++++++++++++++--------------------
1 files changed, 51 insertions(+), 44 deletions(-)

diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
index 8ade0a0481c6..f092fa14a745 100644
--- a/crypto/async_tx/async_xor.c
+++ b/crypto/async_tx/async_xor.c
@@ -33,48 +33,32 @@

/* do_async_xor - dma map the pages and perform the xor with an engine */
static __async_inline struct dma_async_tx_descriptor *
-do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
- unsigned int offset, int src_cnt, size_t len, dma_addr_t *dma_src,
+do_async_xor(struct dma_chan *chan, struct dmaengine_unmap_data *unmap,
struct async_submit_ctl *submit)
{
struct dma_device *dma = chan->device;
struct dma_async_tx_descriptor *tx = NULL;
- int src_off = 0;
- int i;
dma_async_tx_callback cb_fn_orig = submit->cb_fn;
void *cb_param_orig = submit->cb_param;
enum async_tx_flags flags_orig = submit->flags;
enum dma_ctrl_flags dma_flags;
- int xor_src_cnt = 0;
- dma_addr_t dma_dest;
-
- /* map the dest bidrectional in case it is re-used as a source */
- dma_dest = dma_map_page(dma->dev, dest, offset, len, DMA_BIDIRECTIONAL);
- for (i = 0; i < src_cnt; i++) {
- /* only map the dest once */
- if (!src_list[i])
- continue;
- if (unlikely(src_list[i] == dest)) {
- dma_src[xor_src_cnt++] = dma_dest;
- continue;
- }
- dma_src[xor_src_cnt++] = dma_map_page(dma->dev, src_list[i], offset,
- len, DMA_TO_DEVICE);
- }
- src_cnt = xor_src_cnt;
+ int src_cnt = unmap->to_cnt;
+ int xor_src_cnt;
+ dma_addr_t dma_dest = unmap->addr[unmap->to_cnt];
+ dma_addr_t *src_list = unmap->addr;

while (src_cnt) {
+ dma_addr_t tmp;
+
submit->flags = flags_orig;
- dma_flags = 0;
xor_src_cnt = min(src_cnt, (int)dma->max_xor);
- /* if we are submitting additional xors, leave the chain open,
- * clear the callback parameters, and leave the destination
- * buffer mapped
+ /* if we are submitting additional xors, leave the chain open
+ * and clear the callback parameters
*/
+ dma_flags = DMA_COMPL_SKIP_SRC_UNMAP | DMA_COMPL_SKIP_DEST_UNMAP;
if (src_cnt > xor_src_cnt) {
submit->flags &= ~ASYNC_TX_ACK;
submit->flags |= ASYNC_TX_FENCE;
- dma_flags = DMA_COMPL_SKIP_DEST_UNMAP;
submit->cb_fn = NULL;
submit->cb_param = NULL;
} else {
@@ -85,12 +69,18 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
dma_flags |= DMA_PREP_INTERRUPT;
if (submit->flags & ASYNC_TX_FENCE)
dma_flags |= DMA_PREP_FENCE;
- /* Since we have clobbered the src_list we are committed
- * to doing this asynchronously. Drivers force forward progress
- * in case they can not provide a descriptor
+
+ /* Drivers force forward progress in case they can not provide a
+ * descriptor
*/
- tx = dma->device_prep_dma_xor(chan, dma_dest, &dma_src[src_off],
- xor_src_cnt, len, dma_flags);
+ tmp = src_list[0];
+ if (src_list > unmap->addr)
+ src_list[0] = dma_dest;
+ tx = dma->device_prep_dma_xor(chan, dma_dest, src_list,
+ xor_src_cnt, unmap->len,
+ dma_flags);
+ src_list[0] = tmp;
+

if (unlikely(!tx))
async_tx_quiesce(&submit->depend_tx);
@@ -99,22 +89,21 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
while (unlikely(!tx)) {
dma_async_issue_pending(chan);
tx = dma->device_prep_dma_xor(chan, dma_dest,
- &dma_src[src_off],
- xor_src_cnt, len,
+ src_list,
+ xor_src_cnt, unmap->len,
dma_flags);
}

+ dma_set_unmap(tx, unmap);
async_tx_submit(chan, tx, submit);
submit->depend_tx = tx;

if (src_cnt > xor_src_cnt) {
/* drop completed sources */
src_cnt -= xor_src_cnt;
- src_off += xor_src_cnt;
-
/* use the intermediate result a source */
- dma_src[--src_off] = dma_dest;
src_cnt++;
+ src_list += xor_src_cnt - 1;
} else
break;
}
@@ -189,22 +178,40 @@ async_xor(struct page *dest, struct page **src_list, unsigned int offset,
struct dma_chan *chan = async_tx_find_channel(submit, DMA_XOR,
&dest, 1, src_list,
src_cnt, len);
- dma_addr_t *dma_src = NULL;
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dmaengine_unmap_data *unmap = NULL;

BUG_ON(src_cnt <= 1);

- if (submit->scribble)
- dma_src = submit->scribble;
- else if (sizeof(dma_addr_t) <= sizeof(struct page *))
- dma_src = (dma_addr_t *) src_list;
+ if (device)
+ unmap = dmaengine_get_unmap_data(device->dev, src_cnt+1, GFP_NOIO);
+
+ if (unmap && is_dma_xor_aligned(device, offset, 0, len)) {
+ struct dma_async_tx_descriptor *tx;
+ int i, j;

- if (dma_src && chan && is_dma_xor_aligned(chan->device, offset, 0, len)) {
/* run the xor asynchronously */
pr_debug("%s (async): len: %zu\n", __func__, len);

- return do_async_xor(chan, dest, src_list, offset, src_cnt, len,
- dma_src, submit);
+ unmap->len = len;
+ for (i = 0, j = 0; i < src_cnt; i++) {
+ if (!src_list[i])
+ continue;
+ unmap->to_cnt++;
+ unmap->addr[j++] = dma_map_page(device->dev, src_list[i],
+ offset, len, DMA_TO_DEVICE);
+ }
+
+ /* map it bidirectional as it may be re-used as a source */
+ unmap->addr[j] = dma_map_page(device->dev, dest, offset, len,
+ DMA_BIDIRECTIONAL);
+ unmap->bidi_cnt = 1;
+
+ tx = do_async_xor(chan, unmap, submit);
+ dmaengine_unmap_put(unmap);
+ return tx;
} else {
+ dmaengine_unmap_put(unmap);
/* run the xor synchronously */
pr_debug("%s (sync): len: %zu\n", __func__, len);
WARN_ONCE(chan, "%s: no space for dma address conversion\n",

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