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_FENCE: specify that the next operation in the dependency
  62 * chain uses this operation's result as an input
  63 */
  64enum async_tx_flags {
  65        ASYNC_TX_XOR_ZERO_DST    = (1 << 0),
  66        ASYNC_TX_XOR_DROP_DST    = (1 << 1),
  67        ASYNC_TX_ACK             = (1 << 2),
  68        ASYNC_TX_FENCE           = (1 << 3),
  69};
  70
  71/**
  72 * struct async_submit_ctl - async_tx submission/completion modifiers
  73 * @flags: submission modifiers
  74 * @depend_tx: parent dependency of the current operation being submitted
  75 * @cb_fn: callback routine to run at operation completion
  76 * @cb_param: parameter for the callback routine
  77 * @scribble: caller provided space for dma/page address conversions
  78 */
  79struct async_submit_ctl {
  80        enum async_tx_flags flags;
  81        struct dma_async_tx_descriptor *depend_tx;
  82        dma_async_tx_callback cb_fn;
  83        void *cb_param;
  84        void *scribble;
  85};
  86
  87#ifdef CONFIG_DMA_ENGINE
  88#define async_tx_issue_pending_all dma_issue_pending_all
  89
  90/**
  91 * async_tx_issue_pending - send pending descriptor to the hardware channel
  92 * @tx: descriptor handle to retrieve hardware context
  93 *
  94 * Note: any dependent operations will have already been issued by
  95 * async_tx_channel_switch, or (in the case of no channel switch) will
  96 * be already pending on this channel.
  97 */
  98static inline void async_tx_issue_pending(struct dma_async_tx_descriptor *tx)
  99{
 100        if (likely(tx)) {
 101                struct dma_chan *chan = tx->chan;
 102                struct dma_device *dma = chan->device;
 103
 104                dma->device_issue_pending(chan);
 105        }
 106}
 107#ifdef CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL
 108#include <asm/async_tx.h>
 109#else
 110#define async_tx_find_channel(dep, type, dst, dst_count, src, src_count, len) \
 111         __async_tx_find_channel(dep, type)
 112struct dma_chan *
 113__async_tx_find_channel(struct async_submit_ctl *submit,
 114                        enum dma_transaction_type tx_type);
 115#endif /* CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL */
 116#else
 117static inline void async_tx_issue_pending_all(void)
 118{
 119        do { } while (0);
 120}
 121
 122static inline void async_tx_issue_pending(struct dma_async_tx_descriptor *tx)
 123{
 124        do { } while (0);
 125}
 126
 127static inline struct dma_chan *
 128async_tx_find_channel(struct async_submit_ctl *submit,
 129                      enum dma_transaction_type tx_type, struct page **dst,
 130                      int dst_count, struct page **src, int src_count,
 131                      size_t len)
 132{
 133        return NULL;
 134}
 135#endif
 136
 137/**
 138 * async_tx_sync_epilog - actions to take if an operation is run synchronously
 139 * @cb_fn: function to call when the transaction completes
 140 * @cb_fn_param: parameter to pass to the callback routine
 141 */
 142static inline void
 143async_tx_sync_epilog(struct async_submit_ctl *submit)
 144{
 145        if (submit->cb_fn)
 146                submit->cb_fn(submit->cb_param);
 147}
 148
 149typedef union {
 150        unsigned long addr;
 151        struct page *page;
 152        dma_addr_t dma;
 153} addr_conv_t;
 154
 155static inline void
 156init_async_submit(struct async_submit_ctl *args, enum async_tx_flags flags,
 157                  struct dma_async_tx_descriptor *tx,
 158                  dma_async_tx_callback cb_fn, void *cb_param,
 159                  addr_conv_t *scribble)
 160{
 161        args->flags = flags;
 162        args->depend_tx = tx;
 163        args->cb_fn = cb_fn;
 164        args->cb_param = cb_param;
 165        args->scribble = scribble;
 166}
 167
 168void async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
 169                     struct async_submit_ctl *submit);
 170
 171struct dma_async_tx_descriptor *
 172async_xor(struct page *dest, struct page **src_list, unsigned int offset,
 173          int src_cnt, size_t len, struct async_submit_ctl *submit);
 174
 175struct dma_async_tx_descriptor *
 176async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
 177              int src_cnt, size_t len, enum sum_check_flags *result,
 178              struct async_submit_ctl *submit);
 179
 180struct dma_async_tx_descriptor *
 181async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
 182             unsigned int src_offset, size_t len,
 183             struct async_submit_ctl *submit);
 184
 185struct dma_async_tx_descriptor *async_trigger_callback(struct async_submit_ctl *submit);
 186
 187struct dma_async_tx_descriptor *
 188async_gen_syndrome(struct page **blocks, unsigned int offset, int src_cnt,
 189                   size_t len, struct async_submit_ctl *submit);
 190
 191struct dma_async_tx_descriptor *
 192async_syndrome_val(struct page **blocks, unsigned int offset, int src_cnt,
 193                   size_t len, enum sum_check_flags *pqres, struct page *spare,
 194                   struct async_submit_ctl *submit);
 195
 196struct dma_async_tx_descriptor *
 197async_raid6_2data_recov(int src_num, size_t bytes, int faila, int failb,
 198                        struct page **ptrs, struct async_submit_ctl *submit);
 199
 200struct dma_async_tx_descriptor *
 201async_raid6_datap_recov(int src_num, size_t bytes, int faila,
 202                        struct page **ptrs, struct async_submit_ctl *submit);
 203
 204void async_tx_quiesce(struct dma_async_tx_descriptor **tx);
 205#endif /* _ASYNC_TX_H_ */
 206