xref: /linux-6.15/include/linux/async_tx.h (revision b2f46fd8)
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  */
42 struct 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  */
62 enum async_tx_flags {
63 	ASYNC_TX_XOR_ZERO_DST	 = (1 << 0),
64 	ASYNC_TX_XOR_DROP_DST	 = (1 << 1),
65 	ASYNC_TX_ACK		 = (1 << 2),
66 };
67 
68 /**
69  * struct async_submit_ctl - async_tx submission/completion modifiers
70  * @flags: submission modifiers
71  * @depend_tx: parent dependency of the current operation being submitted
72  * @cb_fn: callback routine to run at operation completion
73  * @cb_param: parameter for the callback routine
74  * @scribble: caller provided space for dma/page address conversions
75  */
76 struct async_submit_ctl {
77 	enum async_tx_flags flags;
78 	struct dma_async_tx_descriptor *depend_tx;
79 	dma_async_tx_callback cb_fn;
80 	void *cb_param;
81 	void *scribble;
82 };
83 
84 #ifdef CONFIG_DMA_ENGINE
85 #define async_tx_issue_pending_all dma_issue_pending_all
86 
87 /**
88  * async_tx_issue_pending - send pending descriptor to the hardware channel
89  * @tx: descriptor handle to retrieve hardware context
90  *
91  * Note: any dependent operations will have already been issued by
92  * async_tx_channel_switch, or (in the case of no channel switch) will
93  * be already pending on this channel.
94  */
95 static inline void async_tx_issue_pending(struct dma_async_tx_descriptor *tx)
96 {
97 	if (likely(tx)) {
98 		struct dma_chan *chan = tx->chan;
99 		struct dma_device *dma = chan->device;
100 
101 		dma->device_issue_pending(chan);
102 	}
103 }
104 #ifdef CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL
105 #include <asm/async_tx.h>
106 #else
107 #define async_tx_find_channel(dep, type, dst, dst_count, src, src_count, len) \
108 	 __async_tx_find_channel(dep, type)
109 struct dma_chan *
110 __async_tx_find_channel(struct async_submit_ctl *submit,
111 			enum dma_transaction_type tx_type);
112 #endif /* CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL */
113 #else
114 static inline void async_tx_issue_pending_all(void)
115 {
116 	do { } while (0);
117 }
118 
119 static inline void async_tx_issue_pending(struct dma_async_tx_descriptor *tx)
120 {
121 	do { } while (0);
122 }
123 
124 static inline struct dma_chan *
125 async_tx_find_channel(struct async_submit_ctl *submit,
126 		      enum dma_transaction_type tx_type, struct page **dst,
127 		      int dst_count, struct page **src, int src_count,
128 		      size_t len)
129 {
130 	return NULL;
131 }
132 #endif
133 
134 /**
135  * async_tx_sync_epilog - actions to take if an operation is run synchronously
136  * @cb_fn: function to call when the transaction completes
137  * @cb_fn_param: parameter to pass to the callback routine
138  */
139 static inline void
140 async_tx_sync_epilog(struct async_submit_ctl *submit)
141 {
142 	if (submit->cb_fn)
143 		submit->cb_fn(submit->cb_param);
144 }
145 
146 typedef union {
147 	unsigned long addr;
148 	struct page *page;
149 	dma_addr_t dma;
150 } addr_conv_t;
151 
152 static inline void
153 init_async_submit(struct async_submit_ctl *args, enum async_tx_flags flags,
154 		  struct dma_async_tx_descriptor *tx,
155 		  dma_async_tx_callback cb_fn, void *cb_param,
156 		  addr_conv_t *scribble)
157 {
158 	args->flags = flags;
159 	args->depend_tx = tx;
160 	args->cb_fn = cb_fn;
161 	args->cb_param = cb_param;
162 	args->scribble = scribble;
163 }
164 
165 void async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
166 		     struct async_submit_ctl *submit);
167 
168 struct dma_async_tx_descriptor *
169 async_xor(struct page *dest, struct page **src_list, unsigned int offset,
170 	  int src_cnt, size_t len, struct async_submit_ctl *submit);
171 
172 struct dma_async_tx_descriptor *
173 async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
174 	      int src_cnt, size_t len, enum sum_check_flags *result,
175 	      struct async_submit_ctl *submit);
176 
177 struct dma_async_tx_descriptor *
178 async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
179 	     unsigned int src_offset, size_t len,
180 	     struct async_submit_ctl *submit);
181 
182 struct dma_async_tx_descriptor *
183 async_memset(struct page *dest, int val, unsigned int offset,
184 	     size_t len, struct async_submit_ctl *submit);
185 
186 struct dma_async_tx_descriptor *async_trigger_callback(struct async_submit_ctl *submit);
187 
188 struct dma_async_tx_descriptor *
189 async_gen_syndrome(struct page **blocks, unsigned int offset, int src_cnt,
190 		   size_t len, struct async_submit_ctl *submit);
191 
192 struct dma_async_tx_descriptor *
193 async_syndrome_val(struct page **blocks, unsigned int offset, int src_cnt,
194 		   size_t len, enum sum_check_flags *pqres, struct page *spare,
195 		   struct async_submit_ctl *submit);
196 
197 void async_tx_quiesce(struct dma_async_tx_descriptor **tx);
198 #endif /* _ASYNC_TX_H_ */
199