LXR linux/include/linux/async

   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 */
  42struct 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 */
  63enum 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)
  77struct 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
  82static inline void async_tx_issue_pending_all(void)
  83{
  84        do { } while (0);
  85}
  86
  87static inline struct dma_chan *
  88async_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 */
 101static inline void
 102async_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
 108void
 109async_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
 113struct dma_async_tx_descriptor *
 114async_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
 119struct dma_async_tx_descriptor *
 120async_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
 126struct dma_async_tx_descriptor *
 127async_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
 132struct dma_async_tx_descriptor *
 133async_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
 138struct dma_async_tx_descriptor *
 139async_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
 143void async_tx_quiesce(struct dma_async_tx_descriptor **tx);
 144#endif /* _ASYNC_TX_H_ */
 145