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 /* on architectures without dma-mapping capabilities we need to ensure
  25  * that the asynchronous path compiles away
  26  */
  27 #ifdef CONFIG_HAS_DMA
  28 #define __async_inline
  29 #else
  30 #define __async_inline __always_inline
  31 #endif
  32
  33 /**
  34  * dma_chan_ref - object used to manage dma channels received from the
  35  *   dmaengine core.
  36  * @chan - the channel being tracked
  37  * @node - node for the channel to be placed on async_tx_master_list
  38  * @rcu - for list_del_rcu
  39  * @count - number of times this channel is listed in the pool
  40  *      (for channels with multiple capabiities)
  41  */
  42 struct dma_chan_ref {
  43         struct dma_chan *chan;
  44         struct list_head node;
  45         struct rcu_head rcu;
  46         atomic_t count;
  47 };
  48
  49 /**
  50  * async_tx_flags - modifiers for the async_* calls
  51  * @ASYNC_TX_XOR_ZERO_DST: this flag must be used for xor operations where the
  52  * the destination address is not a source.  The asynchronous case handles this
  53  * implicitly, the synchronous case needs to zero the destination block.
  54  * @ASYNC_TX_XOR_DROP_DST: this flag must be used if the destination address is
  55  * also one of the source addresses.  In the synchronous case the destination
  56  * address is an implied source, whereas the asynchronous case it must be listed
  57  * as a source.  The destination address must be the first address in the source
  58  * array.
  59  * @ASYNC_TX_ACK: immediately ack the descriptor, precludes setting up a
  60  * dependency chain
  61  * @ASYNC_TX_DEP_ACK: ack the dependency descriptor.  Useful for chaining.
  62  */
  63 enum async_tx_flags {
  64         ASYNC_TX_XOR_ZERO_DST    = (1 << 0),
  65         ASYNC_TX_XOR_DROP_DST    = (1 << 1),
  66         ASYNC_TX_ACK             = (1 << 3),
  67         ASYNC_TX_DEP_ACK         = (1 << 4),
  68 };
  69
  70 #ifdef CONFIG_DMA_ENGINE
  71 #define async_tx_issue_pending_all dma_issue_pending_all
  72 #ifdef CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL
  73 #include <asm/async_tx.h>
  74 #else
  75 #define async_tx_find_channel(dep, type, dst, dst_count, src, src_count, len) \
  76          __async_tx_find_channel(dep, type)
  77 struct dma_chan *
  78 __async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
  79         enum dma_transaction_type tx_type);
  80 #endif /* CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL */
  81 #else
  82 static inline void async_tx_issue_pending_all(void)
  83 {
  84         do { } while (0);
  85 }
  86
  87 static inline struct dma_chan *
  88 async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
  89         enum dma_transaction_type tx_type, struct page **dst, int dst_count,
  90         struct page **src, int src_count, size_t len)
  91 {
  92         return NULL;
  93 }
  94 #endif
  95
  96 /**
  97  * async_tx_sync_epilog - actions to take if an operation is run synchronously
  98  * @cb_fn: function to call when the transaction completes
  99  * @cb_fn_param: parameter to pass to the callback routine
 100  */
 101 static inline void
 102 async_tx_sync_epilog(dma_async_tx_callback cb_fn, void *cb_fn_param)
 103 {
 104         if (cb_fn)
 105                 cb_fn(cb_fn_param);
 106 }
 107
 108 void
 109 async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
 110         enum async_tx_flags flags, struct dma_async_tx_descriptor *depend_tx,
 111         dma_async_tx_callback cb_fn, void *cb_fn_param);
 112
 113 struct dma_async_tx_descriptor *
 114 async_xor(struct page *dest, struct page **src_list, unsigned int offset,
 115         int src_cnt, size_t len, enum async_tx_flags flags,
 116         struct dma_async_tx_descriptor *depend_tx,
 117         dma_async_tx_callback cb_fn, void *cb_fn_param);
 118
 119 struct dma_async_tx_descriptor *
 120 async_xor_zero_sum(struct page *dest, struct page **src_list,
 121         unsigned int offset, int src_cnt, size_t len,
 122         u32 *result, enum async_tx_flags flags,
 123         struct dma_async_tx_descriptor *depend_tx,
 124         dma_async_tx_callback cb_fn, void *cb_fn_param);
 125
 126 struct dma_async_tx_descriptor *
 127 async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
 128         unsigned int src_offset, size_t len, enum async_tx_flags flags,
 129         struct dma_async_tx_descriptor *depend_tx,
 130         dma_async_tx_callback cb_fn, void *cb_fn_param);
 131
 132 struct dma_async_tx_descriptor *
 133 async_memset(struct page *dest, int val, unsigned int offset,
 134         size_t len, enum async_tx_flags flags,
 135         struct dma_async_tx_descriptor *depend_tx,
 136         dma_async_tx_callback cb_fn, void *cb_fn_param);
 137
 138 struct dma_async_tx_descriptor *
 139 async_trigger_callback(enum async_tx_flags flags,
 140         struct dma_async_tx_descriptor *depend_tx,
 141         dma_async_tx_callback cb_fn, void *cb_fn_param);
 142
 143 void async_tx_quiesce(struct dma_async_tx_descriptor **tx);
 144 #endif /* _ASYNC_TX_H_ */