xref: /linux/drivers/md/dm-vdo/vio.h (revision 306ec721d043bbe5e818d59fbb37c28d999b5d8b)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright 2023 Red Hat
4  */
5 
6 #ifndef VIO_H
7 #define VIO_H
8 
9 #include <linux/bio.h>
10 #include <linux/blkdev.h>
11 #include <linux/compiler.h>
12 #include <linux/kernel.h>
13 #include <linux/list.h>
14 
15 #include "completion.h"
16 #include "constants.h"
17 #include "types.h"
18 #include "vdo.h"
19 
20 enum {
21 	MAX_BLOCKS_PER_VIO = (BIO_MAX_VECS << PAGE_SHIFT) / VDO_BLOCK_SIZE,
22 };
23 
24 struct pooled_vio {
25 	/* The underlying vio */
26 	struct vio vio;
27 	/* The list entry for chaining pooled vios together */
28 	struct list_head list_entry;
29 	/* The context set by the pool */
30 	void *context;
31 	/* The list entry used by the pool */
32 	struct list_head pool_entry;
33 };
34 
35 /**
36  * as_vio() - Convert a generic vdo_completion to a vio.
37  * @completion: The completion to convert.
38  *
39  * Return: The completion as a vio.
40  */
41 static inline struct vio *as_vio(struct vdo_completion *completion)
42 {
43 	vdo_assert_completion_type(completion, VIO_COMPLETION);
44 	return container_of(completion, struct vio, completion);
45 }
46 
47 /**
48  * get_vio_bio_zone_thread_id() - Get the thread id of the bio zone in which a vio should submit
49  *                                its I/O.
50  * @vio: The vio.
51  *
52  * Return: The id of the bio zone thread the vio should use.
53  */
54 static inline thread_id_t __must_check get_vio_bio_zone_thread_id(struct vio *vio)
55 {
56 	return vio->completion.vdo->thread_config.bio_threads[vio->bio_zone];
57 }
58 
59 physical_block_number_t __must_check pbn_from_vio_bio(struct bio *bio);
60 
61 /**
62  * assert_vio_in_bio_zone() - Check that a vio is running on the correct thread for its bio zone.
63  * @vio: The vio to check.
64  */
65 static inline void assert_vio_in_bio_zone(struct vio *vio)
66 {
67 	thread_id_t expected = get_vio_bio_zone_thread_id(vio);
68 	thread_id_t thread_id = vdo_get_callback_thread_id();
69 
70 	VDO_ASSERT_LOG_ONLY((expected == thread_id),
71 			    "vio I/O for physical block %llu on thread %u, should be on bio zone thread %u",
72 			    (unsigned long long) pbn_from_vio_bio(vio->bio), thread_id,
73 			    expected);
74 }
75 
76 int vdo_create_bio(struct bio **bio_ptr);
77 void vdo_free_bio(struct bio *bio);
78 int allocate_vio_components(struct vdo *vdo, enum vio_type vio_type,
79 			    enum vio_priority priority, void *parent,
80 			    unsigned int block_count, char *data, struct vio *vio);
81 int __must_check create_multi_block_metadata_vio(struct vdo *vdo, enum vio_type vio_type,
82 						 enum vio_priority priority,
83 						 void *parent, unsigned int block_count,
84 						 char *data, struct vio **vio_ptr);
85 
86 static inline int __must_check create_metadata_vio(struct vdo *vdo, enum vio_type vio_type,
87 						   enum vio_priority priority,
88 						   void *parent, char *data,
89 						   struct vio **vio_ptr)
90 {
91 	return create_multi_block_metadata_vio(vdo, vio_type, priority, parent, 1, data,
92 					       vio_ptr);
93 }
94 
95 void free_vio_components(struct vio *vio);
96 void free_vio(struct vio *vio);
97 
98 /**
99  * initialize_vio() - Initialize a vio.
100  * @vio: The vio to initialize.
101  * @bio: The bio this vio should use for its I/O.
102  * @block_count: The size of this vio in vdo blocks.
103  * @vio_type: The vio type.
104  * @priority: The relative priority of the vio.
105  * @vdo: The vdo for this vio.
106  */
107 static inline void initialize_vio(struct vio *vio, struct bio *bio,
108 				  unsigned int block_count, enum vio_type vio_type,
109 				  enum vio_priority priority, struct vdo *vdo)
110 {
111 	/* data_vio's may not span multiple blocks */
112 	BUG_ON((vio_type == VIO_TYPE_DATA) && (block_count != 1));
113 
114 	vio->bio = bio;
115 	vio->block_count = block_count;
116 	vio->type = vio_type;
117 	vio->priority = priority;
118 	vdo_initialize_completion(&vio->completion, vdo, VIO_COMPLETION);
119 }
120 
121 void vdo_set_bio_properties(struct bio *bio, struct vio *vio, bio_end_io_t callback,
122 			    blk_opf_t bi_opf, physical_block_number_t pbn);
123 
124 int vio_reset_bio(struct vio *vio, char *data, bio_end_io_t callback,
125 		  blk_opf_t bi_opf, physical_block_number_t pbn);
126 
127 void update_vio_error_stats(struct vio *vio, const char *format, ...)
128 	__printf(2, 3);
129 
130 /**
131  * is_data_vio() - Check whether a vio is servicing an external data request.
132  * @vio: The vio to check.
133  */
134 static inline bool is_data_vio(struct vio *vio)
135 {
136 	return (vio->type == VIO_TYPE_DATA);
137 }
138 
139 /**
140  * get_metadata_priority() - Convert a vio's priority to a work item priority.
141  * @vio: The vio.
142  *
143  * Return: The priority with which to submit the vio's bio.
144  */
145 static inline enum vdo_completion_priority get_metadata_priority(struct vio *vio)
146 {
147 	return ((vio->priority == VIO_PRIORITY_HIGH) ?
148 		BIO_Q_HIGH_PRIORITY :
149 		BIO_Q_METADATA_PRIORITY);
150 }
151 
152 /**
153  * continue_vio() - Enqueue a vio to run its next callback.
154  * @vio: The vio to continue.
155  *
156  * Return: The result of the current operation.
157  */
158 static inline void continue_vio(struct vio *vio, int result)
159 {
160 	if (unlikely(result != VDO_SUCCESS))
161 		vdo_set_completion_result(&vio->completion, result);
162 
163 	vdo_enqueue_completion(&vio->completion, VDO_WORK_Q_DEFAULT_PRIORITY);
164 }
165 
166 void vdo_count_bios(struct atomic_bio_stats *bio_stats, struct bio *bio);
167 void vdo_count_completed_bios(struct bio *bio);
168 
169 /**
170  * continue_vio_after_io() - Continue a vio now that its I/O has returned.
171  */
172 static inline void continue_vio_after_io(struct vio *vio, vdo_action_fn callback,
173 					 thread_id_t thread)
174 {
175 	vdo_count_completed_bios(vio->bio);
176 	vdo_set_completion_callback(&vio->completion, callback, thread);
177 	continue_vio(vio, blk_status_to_errno(vio->bio->bi_status));
178 }
179 
180 void vio_record_metadata_io_error(struct vio *vio);
181 
182 /* A vio_pool is a collection of preallocated vios used to write arbitrary metadata blocks. */
183 
184 static inline struct pooled_vio *vio_as_pooled_vio(struct vio *vio)
185 {
186 	return container_of(vio, struct pooled_vio, vio);
187 }
188 
189 struct vio_pool;
190 
191 int __must_check make_vio_pool(struct vdo *vdo, size_t pool_size, thread_id_t thread_id,
192 			       enum vio_type vio_type, enum vio_priority priority,
193 			       void *context, struct vio_pool **pool_ptr);
194 void free_vio_pool(struct vio_pool *pool);
195 bool __must_check is_vio_pool_busy(struct vio_pool *pool);
196 void acquire_vio_from_pool(struct vio_pool *pool, struct vdo_waiter *waiter);
197 void return_vio_to_pool(struct vio_pool *pool, struct pooled_vio *vio);
198 
199 #endif /* VIO_H */
200