[libata] restore sg on DMA mapping failure
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index e1346cd..1c1a7ca 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -2622,8 +2622,11 @@
dma_address = dma_map_single(ap->host_set->dev, qc->buf_virt,
sg->length, dir);
- if (dma_mapping_error(dma_address))
+ if (dma_mapping_error(dma_address)) {
+ /* restore sg */
+ sg->length += qc->pad_len;
return -1;
+ }
sg_dma_address(sg) = dma_address;
sg_dma_len(sg) = sg->length;
@@ -2694,8 +2697,11 @@
dir = qc->dma_dir;
n_elem = dma_map_sg(ap->host_set->dev, sg, qc->n_elem, dir);
- if (n_elem < 1)
+ if (n_elem < 1) {
+ /* restore last sg */
+ lsg->length += qc->pad_len;
return -1;
+ }
DPRINTK("%d sg elements mapped\n", n_elem);