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 * @ASYNC_TX_PQ_XOR_DST: do not overwrite the syndrome but XOR it with the
  64 * input data. Required for rmw case.
  65 */
  66enum async_tx_flags {
  67        ASYNC_TX_XOR_ZERO_DST    = (1 << 0),
  68        ASYNC_TX_XOR_DROP_DST    = (1 << 1),
  69        ASYNC_TX_ACK             = (1 << 2),
  70        ASYNC_TX_FENCE           = (1 << 3),
  71        ASYNC_TX_PQ_XOR_DST      = (1 << 4),
  72};
  73
  74/**
  75 * struct async_submit_ctl - async_tx submission/completion modifiers
  76 * @flags: submission modifiers
  77 * @depend_tx: parent dependency of the current operation being submitted
  78 * @cb_fn: callback routine to run at operation completion
  79 * @cb_param: parameter for the callback routine
  80 * @scribble: caller provided space for dma/page address conversions
  81 */
  82struct async_submit_ctl {
  83        enum async_tx_flags flags;
  84        struct dma_async_tx_descriptor *depend_tx;
  85        dma_async_tx_callback cb_fn;
  86        void *cb_param;
  87        void *scribble;
  88};
  89
  90#ifdef CONFIG_DMA_ENGINE
  91#define async_tx_issue_pending_all dma_issue_pending_all
  92
  93/**
  94 * async_tx_issue_pending - send pending descriptor to the hardware channel
  95 * @tx: descriptor handle to retrieve hardware context
  96 *
  97 * Note: any dependent operations will have already been issued by
  98 * async_tx_channel_switch, or (in the case of no channel switch) will
  99 * be already pending on this channel.
 100 */
 101static inline void async_tx_issue_pending(struct dma_async_tx_descriptor *tx)
 102{
 103        if (likely(tx)) {
 104                struct dma_chan *chan = tx->chan;
 105                struct dma_device *dma = chan->device;
 106
 107                dma->device_issue_pending(chan);
 108        }
 109}
 110#ifdef CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL
 111#include <asm/async_tx.h>
 112#else
 113#define async_tx_find_channel(dep, type, dst, dst_count, src, src_count, len) \
 114         __async_tx_find_channel(dep, type)
 115struct dma_chan *
 116__async_tx_find_channel(struct async_submit_ctl *submit,
 117                        enum dma_transaction_type tx_type);
 118#endif /* CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL */
 119#else
 120static inline void async_tx_issue_pending_all(void)
 121{
 122        do { } while (0);
 123}
 124
 125static inline void async_tx_issue_pending(struct dma_async_tx_descriptor *tx)
 126{
 127        do { } while (0);
 128}
 129
 130static inline struct dma_chan *
 131async_tx_find_channel(struct async_submit_ctl *submit,
 132                      enum dma_transaction_type tx_type, struct page **dst,
 133                      int dst_count, struct page **src, int src_count,
 134                      size_t len)
 135{
 136        return NULL;
 137}
 138#endif
 139
 140/**
 141 * async_tx_sync_epilog - actions to take if an operation is run synchronously
 142 * @cb_fn: function to call when the transaction completes
 143 * @cb_fn_param: parameter to pass to the callback routine
 144 */
 145static inline void
 146async_tx_sync_epilog(struct async_submit_ctl *submit)
 147{
 148        if (submit->cb_fn)
 149                submit->cb_fn(submit->cb_param);
 150}
 151
 152typedef union {
 153        unsigned long addr;
 154        struct page *page;
 155        dma_addr_t dma;
 156} addr_conv_t;
 157
 158static inline void
 159init_async_submit(struct async_submit_ctl *args, enum async_tx_flags flags,
 160                  struct dma_async_tx_descriptor *tx,
 161                  dma_async_tx_callback cb_fn, void *cb_param,
 162                  addr_conv_t *scribble)
 163{
 164        args->flags = flags;
 165        args->depend_tx = tx;
 166        args->cb_fn = cb_fn;
 167        args->cb_param = cb_param;
 168        args->scribble = scribble;
 169}
 170
 171void async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
 172                     struct async_submit_ctl *submit);
 173
 174struct dma_async_tx_descriptor *
 175async_xor(struct page *dest, struct page **src_list, unsigned int offset,
 176          int src_cnt, size_t len, struct async_submit_ctl *submit);
 177
 178struct dma_async_tx_descriptor *
 179async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
 180              int src_cnt, size_t len, enum sum_check_flags *result,
 181              struct async_submit_ctl *submit);
 182
 183struct dma_async_tx_descriptor *
 184async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
 185             unsigned int src_offset, size_t len,
 186             struct async_submit_ctl *submit);
 187
 188struct dma_async_tx_descriptor *async_trigger_callback(struct async_submit_ctl *submit);
 189
 190struct dma_async_tx_descriptor *
 191async_gen_syndrome(struct page **blocks, unsigned int offset, int src_cnt,
 192                   size_t len, struct async_submit_ctl *submit);
 193
 194struct dma_async_tx_descriptor *
 195async_syndrome_val(struct page **blocks, unsigned int offset, int src_cnt,
 196                   size_t len, enum sum_check_flags *pqres, struct page *spare,
 197                   struct async_submit_ctl *submit);
 198
 199struct dma_async_tx_descriptor *
 200async_raid6_2data_recov(int src_num, size_t bytes, int faila, int failb,
 201                        struct page **ptrs, struct async_submit_ctl *submit);
 202
 203struct dma_async_tx_descriptor *
 204async_raid6_datap_recov(int src_num, size_t bytes, int faila,
 205                        struct page **ptrs, struct async_submit_ctl *submit);
 206
 207void async_tx_quiesce(struct dma_async_tx_descriptor **tx);
 208#endif /* _ASYNC_TX_H_ */
 209