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