1 files changed, 37 insertions, 7 deletions

diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c
index 35d1e33afd5b..42f6f10fb0cc 100644
--- a/drivers/dma/ioat/dma_v3.c
+++ b/drivers/dma/ioat/dma_v3.c
@@ -378,6 +378,8 @@ static void ioat3_timer_event(unsigned long data)
                         u32 chanerr;
 
                         chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
+                        dev_err(to_dev(chan), "%s: Channel halted (%x)\n",
+                                __func__, chanerr);
                         BUG_ON(is_ioat_bug(chanerr));
                 }
 
@@ -569,7 +571,7 @@ __ioat3_prep_xor_lock(struct dma_chan *c, enum sum_check_flags *result,
         dump_desc_dbg(ioat, compl_desc);
 
         /* we leave the channel locked to ensure in order submission */
-        return &desc->txd;
+        return &compl_desc->txd;
 }
 
 static struct dma_async_tx_descriptor *
@@ -728,7 +730,7 @@ __ioat3_prep_pq_lock(struct dma_chan *c, enum sum_check_flags *result,
         dump_desc_dbg(ioat, compl_desc);
 
         /* we leave the channel locked to ensure in order submission */
-        return &desc->txd;
+        return &compl_desc->txd;
 }
 
 static struct dma_async_tx_descriptor *
@@ -736,10 +738,16 @@ ioat3_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
               unsigned int src_cnt, const unsigned char *scf, size_t len,
               unsigned long flags)
 {
+        /* specify valid address for disabled result */
+        if (flags & DMA_PREP_PQ_DISABLE_P)
+                dst[0] = dst[1];
+        if (flags & DMA_PREP_PQ_DISABLE_Q)
+                dst[1] = dst[0];
+
         /* handle the single source multiply case from the raid6
          * recovery path
          */
-        if (unlikely((flags & DMA_PREP_PQ_DISABLE_P) && src_cnt == 1)) {
+        if ((flags & DMA_PREP_PQ_DISABLE_P) && src_cnt == 1) {
                 dma_addr_t single_source[2];
                 unsigned char single_source_coef[2];
 
@@ -761,6 +769,12 @@ ioat3_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
                   unsigned int src_cnt, const unsigned char *scf, size_t len,
                   enum sum_check_flags *pqres, unsigned long flags)
 {
+        /* specify valid address for disabled result */
+        if (flags & DMA_PREP_PQ_DISABLE_P)
+                pq[0] = pq[1];
+        if (flags & DMA_PREP_PQ_DISABLE_Q)
+                pq[1] = pq[0];
+
         /* the cleanup routine only sets bits on validate failure, it
          * does not clear bits on validate success... so clear it here
          */
@@ -778,9 +792,9 @@ ioat3_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
         dma_addr_t pq[2];
 
         memset(scf, 0, src_cnt);
-        flags |= DMA_PREP_PQ_DISABLE_Q;
         pq[0] = dst;
-        pq[1] = ~0;
+        flags |= DMA_PREP_PQ_DISABLE_Q;
+        pq[1] = dst; /* specify valid address for disabled result */
 
         return __ioat3_prep_pq_lock(chan, NULL, pq, src, src_cnt, scf, len,
                                     flags);
@@ -800,9 +814,9 @@ ioat3_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
         *result = 0;
 
         memset(scf, 0, src_cnt);
-        flags |= DMA_PREP_PQ_DISABLE_Q;
         pq[0] = src[0];
-        pq[1] = ~0;
+        flags |= DMA_PREP_PQ_DISABLE_Q;
+        pq[1] = pq[0]; /* specify valid address for disabled result */
 
         return __ioat3_prep_pq_lock(chan, result, pq, &src[1], src_cnt - 1, scf,
                                     len, flags);
@@ -1117,6 +1131,7 @@ static int __devinit ioat3_dma_self_test(struct ioatdma_device *device)
 int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca)
 {
         struct pci_dev *pdev = device->pdev;
+        int dca_en = system_has_dca_enabled(pdev);
         struct dma_device *dma;
         struct dma_chan *c;
         struct ioat_chan_common *chan;
@@ -1137,6 +1152,11 @@ int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca)
         dma->device_prep_dma_interrupt = ioat3_prep_interrupt_lock;
 
         cap = readl(device->reg_base + IOAT_DMA_CAP_OFFSET);
+
+        /* dca is incompatible with raid operations */
+        if (dca_en && (cap & (IOAT_CAP_XOR|IOAT_CAP_PQ)))
+                cap &= ~(IOAT_CAP_XOR|IOAT_CAP_PQ);
+
         if (cap & IOAT_CAP_XOR) {
                 is_raid_device = true;
                 dma->max_xor = 8;
@@ -1186,6 +1206,16 @@ int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca)
                 device->timer_fn = ioat2_timer_event;
         }
 
+        #ifdef CONFIG_ASYNC_TX_DISABLE_PQ_VAL_DMA
+        dma_cap_clear(DMA_PQ_VAL, dma->cap_mask);
+        dma->device_prep_dma_pq_val = NULL;
+        #endif
+
+        #ifdef CONFIG_ASYNC_TX_DISABLE_XOR_VAL_DMA
+        dma_cap_clear(DMA_XOR_VAL, dma->cap_mask);
+        dma->device_prep_dma_xor_val = NULL;
+        #endif
+
         /* -= IOAT ver.3 workarounds =- */
         /* Write CHANERRMSK_INT with 3E07h to mask out the errors
          * that can cause stability issues for IOAT ver.3