xref: /linux-6.15/include/linux/swiotlb.h (revision cd3bc044)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_SWIOTLB_H
3 #define __LINUX_SWIOTLB_H
4 
5 #include <linux/device.h>
6 #include <linux/dma-direction.h>
7 #include <linux/init.h>
8 #include <linux/types.h>
9 #include <linux/limits.h>
10 #include <linux/spinlock.h>
11 
12 struct device;
13 struct page;
14 struct scatterlist;
15 
16 enum swiotlb_force {
17 	SWIOTLB_NORMAL,		/* Default - depending on HW DMA mask etc. */
18 	SWIOTLB_FORCE,		/* swiotlb=force */
19 	SWIOTLB_NO_FORCE,	/* swiotlb=noforce */
20 };
21 
22 /*
23  * Maximum allowable number of contiguous slabs to map,
24  * must be a power of 2.  What is the appropriate value ?
25  * The complexity of {map,unmap}_single is linearly dependent on this value.
26  */
27 #define IO_TLB_SEGSIZE	128
28 
29 /*
30  * log of the size of each IO TLB slab.  The number of slabs is command line
31  * controllable.
32  */
33 #define IO_TLB_SHIFT 11
34 #define IO_TLB_SIZE (1 << IO_TLB_SHIFT)
35 
36 /* default to 64MB */
37 #define IO_TLB_DEFAULT_SIZE (64UL<<20)
38 
39 extern void swiotlb_init(int verbose);
40 int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);
41 unsigned long swiotlb_size_or_default(void);
42 extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs);
43 extern int swiotlb_late_init_with_default_size(size_t default_size);
44 extern void __init swiotlb_update_mem_attributes(void);
45 
46 phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t phys,
47 		size_t mapping_size, size_t alloc_size,
48 		unsigned int alloc_aligned_mask, enum dma_data_direction dir,
49 		unsigned long attrs);
50 
51 extern void swiotlb_tbl_unmap_single(struct device *hwdev,
52 				     phys_addr_t tlb_addr,
53 				     size_t mapping_size,
54 				     enum dma_data_direction dir,
55 				     unsigned long attrs);
56 
57 void swiotlb_sync_single_for_device(struct device *dev, phys_addr_t tlb_addr,
58 		size_t size, enum dma_data_direction dir);
59 void swiotlb_sync_single_for_cpu(struct device *dev, phys_addr_t tlb_addr,
60 		size_t size, enum dma_data_direction dir);
61 dma_addr_t swiotlb_map(struct device *dev, phys_addr_t phys,
62 		size_t size, enum dma_data_direction dir, unsigned long attrs);
63 
64 #ifdef CONFIG_SWIOTLB
65 extern enum swiotlb_force swiotlb_force;
66 
67 /**
68  * struct io_tlb_mem - IO TLB Memory Pool Descriptor
69  *
70  * @start:	The start address of the swiotlb memory pool. Used to do a quick
71  *		range check to see if the memory was in fact allocated by this
72  *		API.
73  * @end:	The end address of the swiotlb memory pool. Used to do a quick
74  *		range check to see if the memory was in fact allocated by this
75  *		API.
76  * @vaddr:	The vaddr of the swiotlb memory pool. The swiotlb memory pool
77  *		may be remapped in the memory encrypted case and store virtual
78  *		address for bounce buffer operation.
79  * @nslabs:	The number of IO TLB blocks (in groups of 64) between @start and
80  *		@end. For default swiotlb, this is command line adjustable via
81  *		setup_io_tlb_npages.
82  * @used:	The number of used IO TLB block.
83  * @list:	The free list describing the number of free entries available
84  *		from each index.
85  * @index:	The index to start searching in the next round.
86  * @orig_addr:	The original address corresponding to a mapped entry.
87  * @alloc_size:	Size of the allocated buffer.
88  * @lock:	The lock to protect the above data structures in the map and
89  *		unmap calls.
90  * @debugfs:	The dentry to debugfs.
91  * @late_alloc:	%true if allocated using the page allocator
92  * @force_bounce: %true if swiotlb bouncing is forced
93  * @for_alloc:  %true if the pool is used for memory allocation
94  */
95 struct io_tlb_mem {
96 	phys_addr_t start;
97 	phys_addr_t end;
98 	void *vaddr;
99 	unsigned long nslabs;
100 	unsigned long used;
101 	unsigned int index;
102 	spinlock_t lock;
103 	struct dentry *debugfs;
104 	bool late_alloc;
105 	bool force_bounce;
106 	bool for_alloc;
107 	struct io_tlb_slot {
108 		phys_addr_t orig_addr;
109 		size_t alloc_size;
110 		unsigned int list;
111 	} *slots;
112 };
113 extern struct io_tlb_mem io_tlb_default_mem;
114 
115 static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
116 {
117 	struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
118 
119 	return mem && paddr >= mem->start && paddr < mem->end;
120 }
121 
122 static inline bool is_swiotlb_force_bounce(struct device *dev)
123 {
124 	struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
125 
126 	return mem && mem->force_bounce;
127 }
128 
129 void __init swiotlb_exit(void);
130 unsigned int swiotlb_max_segment(void);
131 size_t swiotlb_max_mapping_size(struct device *dev);
132 bool is_swiotlb_active(struct device *dev);
133 void __init swiotlb_adjust_size(unsigned long size);
134 #else
135 #define swiotlb_force SWIOTLB_NO_FORCE
136 static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
137 {
138 	return false;
139 }
140 static inline bool is_swiotlb_force_bounce(struct device *dev)
141 {
142 	return false;
143 }
144 static inline void swiotlb_exit(void)
145 {
146 }
147 static inline unsigned int swiotlb_max_segment(void)
148 {
149 	return 0;
150 }
151 static inline size_t swiotlb_max_mapping_size(struct device *dev)
152 {
153 	return SIZE_MAX;
154 }
155 
156 static inline bool is_swiotlb_active(struct device *dev)
157 {
158 	return false;
159 }
160 
161 static inline void swiotlb_adjust_size(unsigned long size)
162 {
163 }
164 #endif /* CONFIG_SWIOTLB */
165 
166 extern void swiotlb_print_info(void);
167 extern void swiotlb_set_max_segment(unsigned int);
168 
169 #ifdef CONFIG_DMA_RESTRICTED_POOL
170 struct page *swiotlb_alloc(struct device *dev, size_t size);
171 bool swiotlb_free(struct device *dev, struct page *page, size_t size);
172 
173 static inline bool is_swiotlb_for_alloc(struct device *dev)
174 {
175 	return dev->dma_io_tlb_mem->for_alloc;
176 }
177 #else
178 static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
179 {
180 	return NULL;
181 }
182 static inline bool swiotlb_free(struct device *dev, struct page *page,
183 				size_t size)
184 {
185 	return false;
186 }
187 static inline bool is_swiotlb_for_alloc(struct device *dev)
188 {
189 	return false;
190 }
191 #endif /* CONFIG_DMA_RESTRICTED_POOL */
192 
193 extern phys_addr_t swiotlb_unencrypted_base;
194 
195 #endif /* __LINUX_SWIOTLB_H */
196