xref: /linux-6.15/include/linux/iova.h (revision 151f4e2b)
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	*cached_node;	/* Save last alloced node */
74 	struct rb_node	*cached32_node; /* Save last 32-bit alloced node */
75 	unsigned long	granule;	/* pfn granularity for this domain */
76 	unsigned long	start_pfn;	/* Lower limit for this domain */
77 	unsigned long	dma_32bit_pfn;
78 	unsigned long	max32_alloc_size; /* Size of last failed allocation */
79 	struct iova_fq __percpu *fq;	/* Flush Queue */
80 
81 	atomic64_t	fq_flush_start_cnt;	/* Number of TLB flushes that
82 						   have been started */
83 
84 	atomic64_t	fq_flush_finish_cnt;	/* Number of TLB flushes that
85 						   have been finished */
86 
87 	struct iova	anchor;		/* rbtree lookup anchor */
88 	struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];	/* IOVA range caches */
89 
90 	iova_flush_cb	flush_cb;	/* Call-Back function to flush IOMMU
91 					   TLBs */
92 
93 	iova_entry_dtor entry_dtor;	/* IOMMU driver specific destructor for
94 					   iova entry */
95 
96 	struct timer_list fq_timer;		/* Timer to regularily empty the
97 						   flush-queues */
98 	atomic_t fq_timer_on;			/* 1 when timer is active, 0
99 						   when not */
100 };
101 
102 static inline unsigned long iova_size(struct iova *iova)
103 {
104 	return iova->pfn_hi - iova->pfn_lo + 1;
105 }
106 
107 static inline unsigned long iova_shift(struct iova_domain *iovad)
108 {
109 	return __ffs(iovad->granule);
110 }
111 
112 static inline unsigned long iova_mask(struct iova_domain *iovad)
113 {
114 	return iovad->granule - 1;
115 }
116 
117 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
118 {
119 	return iova & iova_mask(iovad);
120 }
121 
122 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
123 {
124 	return ALIGN(size, iovad->granule);
125 }
126 
127 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
128 {
129 	return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
130 }
131 
132 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
133 {
134 	return iova >> iova_shift(iovad);
135 }
136 
137 #if IS_ENABLED(CONFIG_IOMMU_IOVA)
138 int iova_cache_get(void);
139 void iova_cache_put(void);
140 
141 struct iova *alloc_iova_mem(void);
142 void free_iova_mem(struct iova *iova);
143 void free_iova(struct iova_domain *iovad, unsigned long pfn);
144 void __free_iova(struct iova_domain *iovad, struct iova *iova);
145 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
146 	unsigned long limit_pfn,
147 	bool size_aligned);
148 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
149 		    unsigned long size);
150 void queue_iova(struct iova_domain *iovad,
151 		unsigned long pfn, unsigned long pages,
152 		unsigned long data);
153 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
154 			      unsigned long limit_pfn, bool flush_rcache);
155 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
156 	unsigned long pfn_hi);
157 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
158 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
159 	unsigned long start_pfn);
160 int init_iova_flush_queue(struct iova_domain *iovad,
161 			  iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
162 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
163 void put_iova_domain(struct iova_domain *iovad);
164 struct iova *split_and_remove_iova(struct iova_domain *iovad,
165 	struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
166 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
167 #else
168 static inline int iova_cache_get(void)
169 {
170 	return -ENOTSUPP;
171 }
172 
173 static inline void iova_cache_put(void)
174 {
175 }
176 
177 static inline struct iova *alloc_iova_mem(void)
178 {
179 	return NULL;
180 }
181 
182 static inline void free_iova_mem(struct iova *iova)
183 {
184 }
185 
186 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
187 {
188 }
189 
190 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
191 {
192 }
193 
194 static inline struct iova *alloc_iova(struct iova_domain *iovad,
195 				      unsigned long size,
196 				      unsigned long limit_pfn,
197 				      bool size_aligned)
198 {
199 	return NULL;
200 }
201 
202 static inline void free_iova_fast(struct iova_domain *iovad,
203 				  unsigned long pfn,
204 				  unsigned long size)
205 {
206 }
207 
208 static inline void queue_iova(struct iova_domain *iovad,
209 			      unsigned long pfn, unsigned long pages,
210 			      unsigned long data)
211 {
212 }
213 
214 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
215 					    unsigned long size,
216 					    unsigned long limit_pfn,
217 					    bool flush_rcache)
218 {
219 	return 0;
220 }
221 
222 static inline struct iova *reserve_iova(struct iova_domain *iovad,
223 					unsigned long pfn_lo,
224 					unsigned long pfn_hi)
225 {
226 	return NULL;
227 }
228 
229 static inline void copy_reserved_iova(struct iova_domain *from,
230 				      struct iova_domain *to)
231 {
232 }
233 
234 static inline void init_iova_domain(struct iova_domain *iovad,
235 				    unsigned long granule,
236 				    unsigned long start_pfn)
237 {
238 }
239 
240 static inline int init_iova_flush_queue(struct iova_domain *iovad,
241 					iova_flush_cb flush_cb,
242 					iova_entry_dtor entry_dtor)
243 {
244 	return -ENODEV;
245 }
246 
247 static inline struct iova *find_iova(struct iova_domain *iovad,
248 				     unsigned long pfn)
249 {
250 	return NULL;
251 }
252 
253 static inline void put_iova_domain(struct iova_domain *iovad)
254 {
255 }
256 
257 static inline struct iova *split_and_remove_iova(struct iova_domain *iovad,
258 						 struct iova *iova,
259 						 unsigned long pfn_lo,
260 						 unsigned long pfn_hi)
261 {
262 	return NULL;
263 }
264 
265 static inline void free_cpu_cached_iovas(unsigned int cpu,
266 					 struct iova_domain *iovad)
267 {
268 }
269 #endif
270 
271 #endif
272