1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (c) 2006, Intel Corporation.
4  *
5  * Copyright (C) 2006-2008 Intel Corporation
6  * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
7  */
8 
9 #ifndef _IOVA_H_
10 #define _IOVA_H_
11 
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/rbtree.h>
15 #include <linux/dma-mapping.h>
16 
17 /* iova structure */
18 struct iova {
19 	struct rb_node	node;
20 	unsigned long	pfn_hi; /* Highest allocated pfn */
21 	unsigned long	pfn_lo; /* Lowest allocated pfn */
22 };
23 
24 
25 struct iova_rcache;
26 
27 /* holds all the iova translations for a domain */
28 struct iova_domain {
29 	spinlock_t	iova_rbtree_lock; /* Lock to protect update of rbtree */
30 	struct rb_root	rbroot;		/* iova domain rbtree root */
31 	struct rb_node	*cached_node;	/* Save last alloced node */
32 	struct rb_node	*cached32_node; /* Save last 32-bit alloced node */
33 	unsigned long	granule;	/* pfn granularity for this domain */
34 	unsigned long	start_pfn;	/* Lower limit for this domain */
35 	unsigned long	dma_32bit_pfn;
36 	unsigned long	max32_alloc_size; /* Size of last failed allocation */
37 	struct iova	anchor;		/* rbtree lookup anchor */
38 
39 	struct iova_rcache	*rcaches;
40 	struct hlist_node	cpuhp_dead;
41 };
42 
iova_size(struct iova * iova)43 static inline unsigned long iova_size(struct iova *iova)
44 {
45 	return iova->pfn_hi - iova->pfn_lo + 1;
46 }
47 
iova_shift(struct iova_domain * iovad)48 static inline unsigned long iova_shift(struct iova_domain *iovad)
49 {
50 	return __ffs(iovad->granule);
51 }
52 
iova_mask(struct iova_domain * iovad)53 static inline unsigned long iova_mask(struct iova_domain *iovad)
54 {
55 	return iovad->granule - 1;
56 }
57 
iova_offset(struct iova_domain * iovad,dma_addr_t iova)58 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
59 {
60 	return iova & iova_mask(iovad);
61 }
62 
iova_align(struct iova_domain * iovad,size_t size)63 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
64 {
65 	return ALIGN(size, iovad->granule);
66 }
67 
iova_align_down(struct iova_domain * iovad,size_t size)68 static inline size_t iova_align_down(struct iova_domain *iovad, size_t size)
69 {
70 	return ALIGN_DOWN(size, iovad->granule);
71 }
72 
iova_dma_addr(struct iova_domain * iovad,struct iova * iova)73 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
74 {
75 	return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
76 }
77 
iova_pfn(struct iova_domain * iovad,dma_addr_t iova)78 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
79 {
80 	return iova >> iova_shift(iovad);
81 }
82 
83 #if IS_REACHABLE(CONFIG_IOMMU_IOVA)
84 int iova_cache_get(void);
85 void iova_cache_put(void);
86 
87 unsigned long iova_rcache_range(void);
88 
89 void free_iova(struct iova_domain *iovad, unsigned long pfn);
90 void __free_iova(struct iova_domain *iovad, struct iova *iova);
91 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
92 	unsigned long limit_pfn,
93 	bool size_aligned);
94 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
95 		    unsigned long size);
96 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
97 			      unsigned long limit_pfn, bool flush_rcache);
98 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
99 	unsigned long pfn_hi);
100 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
101 	unsigned long start_pfn);
102 int iova_domain_init_rcaches(struct iova_domain *iovad);
103 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
104 void put_iova_domain(struct iova_domain *iovad);
105 #else
iova_cache_get(void)106 static inline int iova_cache_get(void)
107 {
108 	return -ENOTSUPP;
109 }
110 
iova_cache_put(void)111 static inline void iova_cache_put(void)
112 {
113 }
114 
free_iova(struct iova_domain * iovad,unsigned long pfn)115 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
116 {
117 }
118 
__free_iova(struct iova_domain * iovad,struct iova * iova)119 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
120 {
121 }
122 
alloc_iova(struct iova_domain * iovad,unsigned long size,unsigned long limit_pfn,bool size_aligned)123 static inline struct iova *alloc_iova(struct iova_domain *iovad,
124 				      unsigned long size,
125 				      unsigned long limit_pfn,
126 				      bool size_aligned)
127 {
128 	return NULL;
129 }
130 
free_iova_fast(struct iova_domain * iovad,unsigned long pfn,unsigned long size)131 static inline void free_iova_fast(struct iova_domain *iovad,
132 				  unsigned long pfn,
133 				  unsigned long size)
134 {
135 }
136 
alloc_iova_fast(struct iova_domain * iovad,unsigned long size,unsigned long limit_pfn,bool flush_rcache)137 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
138 					    unsigned long size,
139 					    unsigned long limit_pfn,
140 					    bool flush_rcache)
141 {
142 	return 0;
143 }
144 
reserve_iova(struct iova_domain * iovad,unsigned long pfn_lo,unsigned long pfn_hi)145 static inline struct iova *reserve_iova(struct iova_domain *iovad,
146 					unsigned long pfn_lo,
147 					unsigned long pfn_hi)
148 {
149 	return NULL;
150 }
151 
init_iova_domain(struct iova_domain * iovad,unsigned long granule,unsigned long start_pfn)152 static inline void init_iova_domain(struct iova_domain *iovad,
153 				    unsigned long granule,
154 				    unsigned long start_pfn)
155 {
156 }
157 
find_iova(struct iova_domain * iovad,unsigned long pfn)158 static inline struct iova *find_iova(struct iova_domain *iovad,
159 				     unsigned long pfn)
160 {
161 	return NULL;
162 }
163 
put_iova_domain(struct iova_domain * iovad)164 static inline void put_iova_domain(struct iova_domain *iovad)
165 {
166 }
167 
168 #endif
169 
170 #endif
171