raid6/async_tx: handle holes in block list in async_syndrome_val
async_syndrome_val check the P and Q blocks used for RAID6
calculations.
With DDF raid6, some of the data blocks might be NULL, so
this needs to be handled in the same way that async_gen_syndrome
handles it.
As async_syndrome_val calls async_xor, also enhance async_xor
to detect and skip NULL blocks in the list.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
index b459a90..79182dc 100644
--- a/crypto/async_tx/async_xor.c
+++ b/crypto/async_tx/async_xor.c
@@ -44,20 +44,23 @@
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;
+ 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[i] = dma_dest;
+ dma_src[xor_src_cnt++] = dma_dest;
continue;
}
- dma_src[i] = dma_map_page(dma->dev, src_list[i], offset,
- len, DMA_TO_DEVICE);
+ dma_src[xor_src_cnt++] = dma_map_page(dma->dev, src_list[i], offset,
+ len, DMA_TO_DEVICE);
}
+ src_cnt = xor_src_cnt;
while (src_cnt) {
submit->flags = flags_orig;
@@ -123,7 +126,7 @@
int src_cnt, size_t len, struct async_submit_ctl *submit)
{
int i;
- int xor_src_cnt;
+ int xor_src_cnt = 0;
int src_off = 0;
void *dest_buf;
void **srcs;
@@ -135,8 +138,9 @@
/* convert to buffer pointers */
for (i = 0; i < src_cnt; i++)
- srcs[i] = page_address(src_list[i]) + offset;
-
+ if (src_list[i])
+ srcs[xor_src_cnt++] = page_address(src_list[i]) + offset;
+ src_cnt = xor_src_cnt;
/* set destination address */
dest_buf = page_address(dest) + offset;