Merge branch 'md-raid6-accel' into ioat3.2

Conflicts:
	include/linux/dmaengine.h

1 files changed, 105 insertions, 11 deletions

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index ffefba81c818..1012f1abcb54 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -52,11 +52,11 @@ enum dma_status {
 enum dma_transaction_type {
         DMA_MEMCPY,
         DMA_XOR,
-        DMA_PQ_XOR,
+        DMA_PQ,
         DMA_DUAL_XOR,
         DMA_PQ_UPDATE,
-        DMA_ZERO_SUM,
-        DMA_PQ_ZERO_SUM,
+        DMA_XOR_VAL,
+        DMA_PQ_VAL,
         DMA_MEMSET,
         DMA_MEMCPY_CRC32C,
         DMA_INTERRUPT,
@@ -70,18 +70,23 @@ enum dma_transaction_type {
 
 /**
  * enum dma_ctrl_flags - DMA flags to augment operation preparation,
- *      control completion, and communicate status.
+ *  control completion, and communicate status.
  * @DMA_PREP_INTERRUPT - trigger an interrupt (callback) upon completion of
- *      this transaction
+ *  this transaction
  * @DMA_CTRL_ACK - the descriptor cannot be reused until the client
- *      acknowledges receipt, i.e. has has a chance to establish any
- *      dependency chains
+ *  acknowledges receipt, i.e. has has a chance to establish any dependency
+ *  chains
  * @DMA_COMPL_SKIP_SRC_UNMAP - set to disable dma-unmapping the source buffer(s)
  * @DMA_COMPL_SKIP_DEST_UNMAP - set to disable dma-unmapping the destination(s)
  * @DMA_COMPL_SRC_UNMAP_SINGLE - set to do the source dma-unmapping as single
  *      (if not set, do the source dma-unmapping as page)
  * @DMA_COMPL_DEST_UNMAP_SINGLE - set to do the destination dma-unmapping as single
  *      (if not set, do the destination dma-unmapping as page)
+ * @DMA_PREP_PQ_DISABLE_P - prevent generation of P while generating Q
+ * @DMA_PREP_PQ_DISABLE_Q - prevent generation of Q while generating P
+ * @DMA_PREP_CONTINUE - indicate to a driver that it is reusing buffers as
+ *  sources that were the result of a previous operation, in the case of a PQ
+ *  operation it continues the calculation with new sources
  */
 enum dma_ctrl_flags {
         DMA_PREP_INTERRUPT = (1 << 0),
@@ -90,9 +95,31 @@ enum dma_ctrl_flags {
         DMA_COMPL_SKIP_DEST_UNMAP = (1 << 3),
         DMA_COMPL_SRC_UNMAP_SINGLE = (1 << 4),
         DMA_COMPL_DEST_UNMAP_SINGLE = (1 << 5),
+        DMA_PREP_PQ_DISABLE_P = (1 << 6),
+        DMA_PREP_PQ_DISABLE_Q = (1 << 7),
+        DMA_PREP_CONTINUE = (1 << 8),
 };
 
 /**
+ * enum sum_check_bits - bit position of pq_check_flags
+ */
+enum sum_check_bits {
+        SUM_CHECK_P = 0,
+        SUM_CHECK_Q = 1,
+};
+
+/**
+ * enum pq_check_flags - result of async_{xor,pq}_zero_sum operations
+ * @SUM_CHECK_P_RESULT - 1 if xor zero sum error, 0 otherwise
+ * @SUM_CHECK_Q_RESULT - 1 if reed-solomon zero sum error, 0 otherwise
+ */
+enum sum_check_flags {
+        SUM_CHECK_P_RESULT = (1 << SUM_CHECK_P),
+        SUM_CHECK_Q_RESULT = (1 << SUM_CHECK_Q),
+};
+
+
+/**
  * dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
  * See linux/cpumask.h
  */
@@ -213,6 +240,7 @@ struct dma_async_tx_descriptor {
  * @global_node: list_head for global dma_device_list
  * @cap_mask: one or more dma_capability flags
  * @max_xor: maximum number of xor sources, 0 if no capability
+ * @max_pq: maximum number of PQ sources and PQ-continue capability
  * @dev_id: unique device ID
  * @dev: struct device reference for dma mapping api
  * @device_alloc_chan_resources: allocate resources and return the
@@ -220,7 +248,9 @@ struct dma_async_tx_descriptor {
  * @device_free_chan_resources: release DMA channel's resources
  * @device_prep_dma_memcpy: prepares a memcpy operation
  * @device_prep_dma_xor: prepares a xor operation
- * @device_prep_dma_zero_sum: prepares a zero_sum operation
+ * @device_prep_dma_xor_val: prepares a xor validation operation
+ * @device_prep_dma_pq: prepares a pq operation
+ * @device_prep_dma_pq_val: prepares a pqzero_sum operation
  * @device_prep_dma_memset: prepares a memset operation
  * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
  * @device_prep_slave_sg: prepares a slave dma operation
@@ -235,7 +265,9 @@ struct dma_device {
         struct list_head channels;
         struct list_head global_node;
         dma_cap_mask_t  cap_mask;
-        int max_xor;
+        unsigned short max_xor;
+        unsigned short max_pq;
+        #define DMA_HAS_PQ_CONTINUE (1 << 15)
 
         int dev_id;
         struct device *dev;
@@ -249,9 +281,17 @@ struct dma_device {
         struct dma_async_tx_descriptor *(*device_prep_dma_xor)(
                 struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
                 unsigned int src_cnt, size_t len, unsigned long flags);
-        struct dma_async_tx_descriptor *(*device_prep_dma_zero_sum)(
+        struct dma_async_tx_descriptor *(*device_prep_dma_xor_val)(
                 struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
-                size_t len, u32 *result, unsigned long flags);
+                size_t len, enum sum_check_flags *result, unsigned long flags);
+        struct dma_async_tx_descriptor *(*device_prep_dma_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);
+        struct dma_async_tx_descriptor *(*device_prep_dma_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);
         struct dma_async_tx_descriptor *(*device_prep_dma_memset)(
                 struct dma_chan *chan, dma_addr_t dest, int value, size_t len,
                 unsigned long flags);
@@ -270,6 +310,60 @@ struct dma_device {
         void (*device_issue_pending)(struct dma_chan *chan);
 };
 
+static inline void
+dma_set_maxpq(struct dma_device *dma, int maxpq, int has_pq_continue)
+{
+        dma->max_pq = maxpq;
+        if (has_pq_continue)
+                dma->max_pq |= DMA_HAS_PQ_CONTINUE;
+}
+
+static inline bool dmaf_continue(enum dma_ctrl_flags flags)
+{
+        return (flags & DMA_PREP_CONTINUE) == DMA_PREP_CONTINUE;
+}
+
+static inline bool dmaf_p_disabled_continue(enum dma_ctrl_flags flags)
+{
+        enum dma_ctrl_flags mask = DMA_PREP_CONTINUE | DMA_PREP_PQ_DISABLE_P;
+
+        return (flags & mask) == mask;
+}
+
+static inline bool dma_dev_has_pq_continue(struct dma_device *dma)
+{
+        return (dma->max_pq & DMA_HAS_PQ_CONTINUE) == DMA_HAS_PQ_CONTINUE;
+}
+
+static unsigned short dma_dev_to_maxpq(struct dma_device *dma)
+{
+        return dma->max_pq & ~DMA_HAS_PQ_CONTINUE;
+}
+
+/* dma_maxpq - reduce maxpq in the face of continued operations
+ * @dma - dma device with PQ capability
+ * @flags - to check if DMA_PREP_CONTINUE and DMA_PREP_PQ_DISABLE_P are set
+ *
+ * When an engine does not support native continuation we need 3 extra
+ * source slots to reuse P and Q with the following coefficients:
+ * 1/ {00} * P : remove P from Q', but use it as a source for P'
+ * 2/ {01} * Q : use Q to continue Q' calculation
+ * 3/ {00} * Q : subtract Q from P' to cancel (2)
+ *
+ * In the case where P is disabled we only need 1 extra source:
+ * 1/ {01} * Q : use Q to continue Q' calculation
+ */
+static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags)
+{
+        if (dma_dev_has_pq_continue(dma) || !dmaf_continue(flags))
+                return dma_dev_to_maxpq(dma);
+        else if (dmaf_p_disabled_continue(flags))
+                return dma_dev_to_maxpq(dma) - 1;
+        else if (dmaf_continue(flags))
+                return dma_dev_to_maxpq(dma) - 3;
+        BUG();
+}
+
 /* --- public DMA engine API --- */
 
 #ifdef CONFIG_DMA_ENGINE