xref: /linux-6.15/include/linux/iova.h (revision bb7e5ce7)
1 /*
2  * Copyright (c) 2006, Intel Corporation.
3  *
4  * This file is released under the GPLv2.
5  *
6  * Copyright (C) 2006-2008 Intel Corporation
7  * Author: Anil S Keshavamurthy <[email protected]>
8  *
9  */
10 
11 #ifndef _IOVA_H_
12 #define _IOVA_H_
13 
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/rbtree.h>
17 #include <linux/atomic.h>
18 #include <linux/dma-mapping.h>
19 
20 /* iova structure */
21 struct iova {
22 	struct rb_node	node;
23 	unsigned long	pfn_hi; /* Highest allocated pfn */
24 	unsigned long	pfn_lo; /* Lowest allocated pfn */
25 };
26 
27 struct iova_magazine;
28 struct iova_cpu_rcache;
29 
30 #define IOVA_RANGE_CACHE_MAX_SIZE 6	/* log of max cached IOVA range size (in pages) */
31 #define MAX_GLOBAL_MAGS 32	/* magazines per bin */
32 
33 struct iova_rcache {
34 	spinlock_t lock;
35 	unsigned long depot_size;
36 	struct iova_magazine *depot[MAX_GLOBAL_MAGS];
37 	struct iova_cpu_rcache __percpu *cpu_rcaches;
38 };
39 
40 struct iova_domain;
41 
42 /* Call-Back from IOVA code into IOMMU drivers */
43 typedef void (* iova_flush_cb)(struct iova_domain *domain);
44 
45 /* Destructor for per-entry data */
46 typedef void (* iova_entry_dtor)(unsigned long data);
47 
48 /* Number of entries per Flush Queue */
49 #define IOVA_FQ_SIZE	256
50 
51 /* Timeout (in ms) after which entries are flushed from the Flush-Queue */
52 #define IOVA_FQ_TIMEOUT	10
53 
54 /* Flush Queue entry for defered flushing */
55 struct iova_fq_entry {
56 	unsigned long iova_pfn;
57 	unsigned long pages;
58 	unsigned long data;
59 	u64 counter; /* Flush counter when this entrie was added */
60 };
61 
62 /* Per-CPU Flush Queue structure */
63 struct iova_fq {
64 	struct iova_fq_entry entries[IOVA_FQ_SIZE];
65 	unsigned head, tail;
66 	spinlock_t lock;
67 };
68 
69 /* holds all the iova translations for a domain */
70 struct iova_domain {
71 	spinlock_t	iova_rbtree_lock; /* Lock to protect update of rbtree */
72 	struct rb_root	rbroot;		/* iova domain rbtree root */
73 	struct rb_node	*cached32_node; /* Save last alloced node */
74 	unsigned long	granule;	/* pfn granularity for this domain */
75 	unsigned long	start_pfn;	/* Lower limit for this domain */
76 	unsigned long	dma_32bit_pfn;
77 	struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];	/* IOVA range caches */
78 
79 	iova_flush_cb	flush_cb;	/* Call-Back function to flush IOMMU
80 					   TLBs */
81 
82 	iova_entry_dtor entry_dtor;	/* IOMMU driver specific destructor for
83 					   iova entry */
84 
85 	struct iova_fq __percpu *fq;	/* Flush Queue */
86 
87 	atomic64_t	fq_flush_start_cnt;	/* Number of TLB flushes that
88 						   have been started */
89 
90 	atomic64_t	fq_flush_finish_cnt;	/* Number of TLB flushes that
91 						   have been finished */
92 
93 	struct timer_list fq_timer;		/* Timer to regularily empty the
94 						   flush-queues */
95 	atomic_t fq_timer_on;			/* 1 when timer is active, 0
96 						   when not */
97 };
98 
99 static inline unsigned long iova_size(struct iova *iova)
100 {
101 	return iova->pfn_hi - iova->pfn_lo + 1;
102 }
103 
104 static inline unsigned long iova_shift(struct iova_domain *iovad)
105 {
106 	return __ffs(iovad->granule);
107 }
108 
109 static inline unsigned long iova_mask(struct iova_domain *iovad)
110 {
111 	return iovad->granule - 1;
112 }
113 
114 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
115 {
116 	return iova & iova_mask(iovad);
117 }
118 
119 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
120 {
121 	return ALIGN(size, iovad->granule);
122 }
123 
124 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
125 {
126 	return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
127 }
128 
129 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
130 {
131 	return iova >> iova_shift(iovad);
132 }
133 
134 #if IS_ENABLED(CONFIG_IOMMU_IOVA)
135 int iova_cache_get(void);
136 void iova_cache_put(void);
137 
138 struct iova *alloc_iova_mem(void);
139 void free_iova_mem(struct iova *iova);
140 void free_iova(struct iova_domain *iovad, unsigned long pfn);
141 void __free_iova(struct iova_domain *iovad, struct iova *iova);
142 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
143 	unsigned long limit_pfn,
144 	bool size_aligned);
145 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
146 		    unsigned long size);
147 void queue_iova(struct iova_domain *iovad,
148 		unsigned long pfn, unsigned long pages,
149 		unsigned long data);
150 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
151 			      unsigned long limit_pfn);
152 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
153 	unsigned long pfn_hi);
154 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
155 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
156 	unsigned long start_pfn, unsigned long pfn_32bit);
157 int init_iova_flush_queue(struct iova_domain *iovad,
158 			  iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
159 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
160 void put_iova_domain(struct iova_domain *iovad);
161 struct iova *split_and_remove_iova(struct iova_domain *iovad,
162 	struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
163 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
164 #else
165 static inline int iova_cache_get(void)
166 {
167 	return -ENOTSUPP;
168 }
169 
170 static inline void iova_cache_put(void)
171 {
172 }
173 
174 static inline struct iova *alloc_iova_mem(void)
175 {
176 	return NULL;
177 }
178 
179 static inline void free_iova_mem(struct iova *iova)
180 {
181 }
182 
183 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
184 {
185 }
186 
187 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
188 {
189 }
190 
191 static inline struct iova *alloc_iova(struct iova_domain *iovad,
192 				      unsigned long size,
193 				      unsigned long limit_pfn,
194 				      bool size_aligned)
195 {
196 	return NULL;
197 }
198 
199 static inline void free_iova_fast(struct iova_domain *iovad,
200 				  unsigned long pfn,
201 				  unsigned long size)
202 {
203 }
204 
205 static inline void queue_iova(struct iova_domain *iovad,
206 			      unsigned long pfn, unsigned long pages,
207 			      unsigned long data)
208 {
209 }
210 
211 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
212 					    unsigned long size,
213 					    unsigned long limit_pfn)
214 {
215 	return 0;
216 }
217 
218 static inline struct iova *reserve_iova(struct iova_domain *iovad,
219 					unsigned long pfn_lo,
220 					unsigned long pfn_hi)
221 {
222 	return NULL;
223 }
224 
225 static inline void copy_reserved_iova(struct iova_domain *from,
226 				      struct iova_domain *to)
227 {
228 }
229 
230 static inline void init_iova_domain(struct iova_domain *iovad,
231 				    unsigned long granule,
232 				    unsigned long start_pfn,
233 				    unsigned long pfn_32bit)
234 {
235 }
236 
237 static inline int init_iova_flush_queue(struct iova_domain *iovad,
238 					iova_flush_cb flush_cb,
239 					iova_entry_dtor entry_dtor)
240 {
241 	return -ENODEV;
242 }
243 
244 static inline struct iova *find_iova(struct iova_domain *iovad,
245 				     unsigned long pfn)
246 {
247 	return NULL;
248 }
249 
250 static inline void put_iova_domain(struct iova_domain *iovad)
251 {
252 }
253 
254 static inline struct iova *split_and_remove_iova(struct iova_domain *iovad,
255 						 struct iova *iova,
256 						 unsigned long pfn_lo,
257 						 unsigned long pfn_hi)
258 {
259 	return NULL;
260 }
261 
262 static inline void free_cpu_cached_iovas(unsigned int cpu,
263 					 struct iova_domain *iovad)
264 {
265 }
266 #endif
267 
268 #endif
269