include/linux/async_tx.h

   1 /*
   2  * Copyright © 2006, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  16  *
  17  */
  18 #ifndef _ASYNC_TX_H_
  19 #define _ASYNC_TX_H_
  20 #include <linux/dmaengine.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/interrupt.h>
  23
  24 /**
  25  * dma_chan_ref - object used to manage dma channels received from the
  26  *   dmaengine core.
  27  * @chan - the channel being tracked
  28  * @node - node for the channel to be placed on async_tx_master_list
  29  * @rcu - for list_del_rcu
  30  * @count - number of times this channel is listed in the pool
  31  *      (for channels with multiple capabiities)
  32  */
  33 struct dma_chan_ref {
  34         struct dma_chan *chan;
  35         struct list_head node;
  36         struct rcu_head rcu;
  37         atomic_t count;
  38 };
  39
  40 /**
  41  * async_tx_flags - modifiers for the async_* calls
  42  * @ASYNC_TX_XOR_ZERO_DST: this flag must be used for xor operations where the
  43  * the destination address is not a source.  The asynchronous case handles this
  44  * implicitly, the synchronous case needs to zero the destination block.
  45  * @ASYNC_TX_XOR_DROP_DST: this flag must be used if the destination address is
  46  * also one of the source addresses.  In the synchronous case the destination
  47  * address is an implied source, whereas the asynchronous case it must be listed
  48  * as a source.  The destination address must be the first address in the source
  49  * array.
  50  * @ASYNC_TX_ASSUME_COHERENT: skip cache maintenance operations
  51  * @ASYNC_TX_ACK: immediately ack the descriptor, precludes setting up a
  52  * dependency chain
  53  * @ASYNC_TX_DEP_ACK: ack the dependency descriptor.  Useful for chaining.
  54  */
  55 enum async_tx_flags {
  56         ASYNC_TX_XOR_ZERO_DST    = (1 << 0),
  57         ASYNC_TX_XOR_DROP_DST    = (1 << 1),
  58         ASYNC_TX_ASSUME_COHERENT = (1 << 2),
  59         ASYNC_TX_ACK             = (1 << 3),
  60         ASYNC_TX_DEP_ACK         = (1 << 4),
  61 };
  62
  63 #ifdef CONFIG_DMA_ENGINE
  64 void async_tx_issue_pending_all(void);
  65 enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
  66 void async_tx_run_dependencies(struct dma_async_tx_descriptor *tx);
  67 struct dma_chan *
  68 async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
  69         enum dma_transaction_type tx_type);
  70 #else
  71 static inline void async_tx_issue_pending_all(void)
  72 {
  73         do { } while (0);
  74 }
  75
  76 static inline enum dma_status
  77 dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
  78 {
  79         return DMA_SUCCESS;
  80 }
  81
  82 static inline void
  83 async_tx_run_dependencies(struct dma_async_tx_descriptor *tx,
  84         struct dma_chan *host_chan)
  85 {
  86         do { } while (0);
  87 }
  88
  89 static inline struct dma_chan *
  90 async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
  91         enum dma_transaction_type tx_type)
  92 {
  93         return NULL;
  94 }
  95 #endif
  96
  97 /**
  98  * async_tx_sync_epilog - actions to take if an operation is run synchronously
  99  * @flags: async_tx flags
 100  * @depend_tx: transaction depends on depend_tx
 101  * @cb_fn: function to call when the transaction completes
 102  * @cb_fn_param: parameter to pass to the callback routine
 103  */
 104 static inline void
 105 async_tx_sync_epilog(unsigned long flags,
 106         struct dma_async_tx_descriptor *depend_tx,
 107         dma_async_tx_callback cb_fn, void *cb_fn_param)
 108 {
 109         if (cb_fn)
 110                 cb_fn(cb_fn_param);
 111
 112         if (depend_tx && (flags & ASYNC_TX_DEP_ACK))
 113                 async_tx_ack(depend_tx);
 114 }
 115
 116 void
 117 async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
 118         enum async_tx_flags flags, struct dma_async_tx_descriptor *depend_tx,
 119         dma_async_tx_callback cb_fn, void *cb_fn_param);
 120
 121 struct dma_async_tx_descriptor *
 122 async_xor(struct page *dest, struct page **src_list, unsigned int offset,
 123         int src_cnt, size_t len, enum async_tx_flags flags,
 124         struct dma_async_tx_descriptor *depend_tx,
 125         dma_async_tx_callback cb_fn, void *cb_fn_param);
 126
 127 struct dma_async_tx_descriptor *
 128 async_xor_zero_sum(struct page *dest, struct page **src_list,
 129         unsigned int offset, int src_cnt, size_t len,
 130         u32 *result, enum async_tx_flags flags,
 131         struct dma_async_tx_descriptor *depend_tx,
 132         dma_async_tx_callback cb_fn, void *cb_fn_param);
 133
 134 struct dma_async_tx_descriptor *
 135 async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
 136         unsigned int src_offset, size_t len, enum async_tx_flags flags,
 137         struct dma_async_tx_descriptor *depend_tx,
 138         dma_async_tx_callback cb_fn, void *cb_fn_param);
 139
 140 struct dma_async_tx_descriptor *
 141 async_memset(struct page *dest, int val, unsigned int offset,
 142         size_t len, enum async_tx_flags flags,
 143         struct dma_async_tx_descriptor *depend_tx,
 144         dma_async_tx_callback cb_fn, void *cb_fn_param);
 145
 146 struct dma_async_tx_descriptor *
 147 async_trigger_callback(enum async_tx_flags flags,
 148         struct dma_async_tx_descriptor *depend_tx,
 149         dma_async_tx_callback cb_fn, void *cb_fn_param);
 150 #endif /* _ASYNC_TX_H_ */