async_tx: structify submission arguments, add scribble

Prepare the api for the arrival of a new parameter, 'scribble'.  This
will allow callers to identify scratchpad memory for dma address or page
address conversions.  As this adds yet another parameter, take this
opportunity to convert the common submission parameters (flags,
dependency, callback, and callback argument) into an object that is
passed by reference.

Also, take this opportunity to fix up the kerneldoc and add notes about
the relevant ASYNC_TX_* flags for each routine.

[ Impact: moves api pass-by-value parameters to a pass-by-reference struct ]

Signed-off-by: Andre Noll <maan@systemlinux.org>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 54 insertions, 30 deletions

diff --git a/include/linux/async_tx.h b/include/linux/async_tx.h
index 9f14cd540cd2..00cfb637ddf2 100644
--- a/include/linux/async_tx.h
+++ b/include/linux/async_tx.h
@@ -65,6 +65,22 @@ enum async_tx_flags {
         ASYNC_TX_ACK             = (1 << 2),
 };
 
+/**
+ * struct async_submit_ctl - async_tx submission/completion modifiers
+ * @flags: submission modifiers
+ * @depend_tx: parent dependency of the current operation being submitted
+ * @cb_fn: callback routine to run at operation completion
+ * @cb_param: parameter for the callback routine
+ * @scribble: caller provided space for dma/page address conversions
+ */
+struct async_submit_ctl {
+        enum async_tx_flags flags;
+        struct dma_async_tx_descriptor *depend_tx;
+        dma_async_tx_callback cb_fn;
+        void *cb_param;
+        void *scribble;
+};
+
 #ifdef CONFIG_DMA_ENGINE
 #define async_tx_issue_pending_all dma_issue_pending_all
 #ifdef CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL
@@ -73,8 +89,8 @@ enum async_tx_flags {
 #define async_tx_find_channel(dep, type, dst, dst_count, src, src_count, len) \
          __async_tx_find_channel(dep, type)
 struct dma_chan *
-__async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
-        enum dma_transaction_type tx_type);
+__async_tx_find_channel(struct async_submit_ctl *submit,
+                        enum dma_transaction_type tx_type);
 #endif /* CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL */
 #else
 static inline void async_tx_issue_pending_all(void)
@@ -83,9 +99,10 @@ static inline void async_tx_issue_pending_all(void)
 }
 
 static inline struct dma_chan *
-async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
-        enum dma_transaction_type tx_type, struct page **dst, int dst_count,
-        struct page **src, int src_count, size_t len)
+async_tx_find_channel(struct async_submit_ctl *submit,
+                      enum dma_transaction_type tx_type, struct page **dst,
+                      int dst_count, struct page **src, int src_count,
+                      size_t len)
 {
         return NULL;
 }
@@ -97,46 +114,53 @@ async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
  * @cb_fn_param: parameter to pass to the callback routine
  */
 static inline void
-async_tx_sync_epilog(dma_async_tx_callback cb_fn, void *cb_fn_param)
+async_tx_sync_epilog(struct async_submit_ctl *submit)
+{
+        if (submit->cb_fn)
+                submit->cb_fn(submit->cb_param);
+}
+
+typedef union {
+        unsigned long addr;
+        struct page *page;
+        dma_addr_t dma;
+} addr_conv_t;
+
+static inline void
+init_async_submit(struct async_submit_ctl *args, enum async_tx_flags flags,
+                  struct dma_async_tx_descriptor *tx,
+                  dma_async_tx_callback cb_fn, void *cb_param,
+                  addr_conv_t *scribble)
 {
-        if (cb_fn)
-                cb_fn(cb_fn_param);
+        args->flags = flags;
+        args->depend_tx = tx;
+        args->cb_fn = cb_fn;
+        args->cb_param = cb_param;
+        args->scribble = scribble;
 }
 
-void
-async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
-        enum async_tx_flags flags, struct dma_async_tx_descriptor *depend_tx,
-        dma_async_tx_callback cb_fn, void *cb_fn_param);
+void async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
+                     struct async_submit_ctl *submit);
 
 struct dma_async_tx_descriptor *
 async_xor(struct page *dest, struct page **src_list, unsigned int offset,
-        int src_cnt, size_t len, enum async_tx_flags flags,
-        struct dma_async_tx_descriptor *depend_tx,
-        dma_async_tx_callback cb_fn, void *cb_fn_param);
+          int src_cnt, size_t len, struct async_submit_ctl *submit);
 
 struct dma_async_tx_descriptor *
-async_xor_val(struct page *dest, struct page **src_list,
-        unsigned int offset, int src_cnt, size_t len,
-        u32 *result, enum async_tx_flags flags,
-        struct dma_async_tx_descriptor *depend_tx,
-        dma_async_tx_callback cb_fn, void *cb_fn_param);
+async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
+              int src_cnt, size_t len, u32 *result,
+              struct async_submit_ctl *submit);
 
 struct dma_async_tx_descriptor *
 async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
-        unsigned int src_offset, size_t len, enum async_tx_flags flags,
-        struct dma_async_tx_descriptor *depend_tx,
-        dma_async_tx_callback cb_fn, void *cb_fn_param);
+             unsigned int src_offset, size_t len,
+             struct async_submit_ctl *submit);
 
 struct dma_async_tx_descriptor *
 async_memset(struct page *dest, int val, unsigned int offset,
-        size_t len, enum async_tx_flags flags,
-        struct dma_async_tx_descriptor *depend_tx,
-        dma_async_tx_callback cb_fn, void *cb_fn_param);
+             size_t len, struct async_submit_ctl *submit);
 
-struct dma_async_tx_descriptor *
-async_trigger_callback(enum async_tx_flags flags,
-        struct dma_async_tx_descriptor *depend_tx,
-        dma_async_tx_callback cb_fn, void *cb_fn_param);
+struct dma_async_tx_descriptor *async_trigger_callback(struct async_submit_ctl *submit);
 
 void async_tx_quiesce(struct dma_async_tx_descriptor **tx);
 #endif /* _ASYNC_TX_H_ */