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