xref: /linux-6.15/include/linux/iova.h (revision bb4e9af0)
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 <[email protected]>
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/atomic.h>
16 #include <linux/dma-mapping.h>
17 
18 /* iova structure */
19 struct iova {
20 	struct rb_node	node;
21 	unsigned long	pfn_hi; /* Highest allocated pfn */
22 	unsigned long	pfn_lo; /* Lowest allocated pfn */
23 };
24 
25 struct iova_magazine;
26 struct iova_cpu_rcache;
27 
28 #define IOVA_RANGE_CACHE_MAX_SIZE 6	/* log of max cached IOVA range size (in pages) */
29 #define MAX_GLOBAL_MAGS 32	/* magazines per bin */
30 
31 struct iova_rcache {
32 	spinlock_t lock;
33 	unsigned long depot_size;
34 	struct iova_magazine *depot[MAX_GLOBAL_MAGS];
35 	struct iova_cpu_rcache __percpu *cpu_rcaches;
36 };
37 
38 struct iova_domain;
39 
40 /* Call-Back from IOVA code into IOMMU drivers */
41 typedef void (* iova_flush_cb)(struct iova_domain *domain);
42 
43 /* Destructor for per-entry data */
44 typedef void (* iova_entry_dtor)(unsigned long data);
45 
46 /* Number of entries per Flush Queue */
47 #define IOVA_FQ_SIZE	256
48 
49 /* Timeout (in ms) after which entries are flushed from the Flush-Queue */
50 #define IOVA_FQ_TIMEOUT	10
51 
52 /* Flush Queue entry for defered flushing */
53 struct iova_fq_entry {
54 	unsigned long iova_pfn;
55 	unsigned long pages;
56 	unsigned long data;
57 	u64 counter; /* Flush counter when this entrie was added */
58 };
59 
60 /* Per-CPU Flush Queue structure */
61 struct iova_fq {
62 	struct iova_fq_entry entries[IOVA_FQ_SIZE];
63 	unsigned head, tail;
64 	spinlock_t lock;
65 };
66 
67 /* holds all the iova translations for a domain */
68 struct iova_domain {
69 	spinlock_t	iova_rbtree_lock; /* Lock to protect update of rbtree */
70 	struct rb_root	rbroot;		/* iova domain rbtree root */
71 	struct rb_node	*cached_node;	/* Save last alloced node */
72 	struct rb_node	*cached32_node; /* Save last 32-bit alloced node */
73 	unsigned long	granule;	/* pfn granularity for this domain */
74 	unsigned long	start_pfn;	/* Lower limit for this domain */
75 	unsigned long	dma_32bit_pfn;
76 	unsigned long	max32_alloc_size; /* Size of last failed allocation */
77 	struct iova_fq __percpu *fq;	/* Flush Queue */
78 
79 	atomic64_t	fq_flush_start_cnt;	/* Number of TLB flushes that
80 						   have been started */
81 
82 	atomic64_t	fq_flush_finish_cnt;	/* Number of TLB flushes that
83 						   have been finished */
84 
85 	struct iova	anchor;		/* rbtree lookup anchor */
86 	struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];	/* IOVA range caches */
87 
88 	iova_flush_cb	flush_cb;	/* Call-Back function to flush IOMMU
89 					   TLBs */
90 
91 	iova_entry_dtor entry_dtor;	/* IOMMU driver specific destructor for
92 					   iova entry */
93 
94 	struct timer_list fq_timer;		/* Timer to regularily empty the
95 						   flush-queues */
96 	atomic_t fq_timer_on;			/* 1 when timer is active, 0
97 						   when not */
98 };
99 
100 static inline unsigned long iova_size(struct iova *iova)
101 {
102 	return iova->pfn_hi - iova->pfn_lo + 1;
103 }
104 
105 static inline unsigned long iova_shift(struct iova_domain *iovad)
106 {
107 	return __ffs(iovad->granule);
108 }
109 
110 static inline unsigned long iova_mask(struct iova_domain *iovad)
111 {
112 	return iovad->granule - 1;
113 }
114 
115 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
116 {
117 	return iova & iova_mask(iovad);
118 }
119 
120 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
121 {
122 	return ALIGN(size, iovad->granule);
123 }
124 
125 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
126 {
127 	return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
128 }
129 
130 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
131 {
132 	return iova >> iova_shift(iovad);
133 }
134 
135 #if IS_ENABLED(CONFIG_IOMMU_IOVA)
136 int iova_cache_get(void);
137 void iova_cache_put(void);
138 
139 struct iova *alloc_iova_mem(void);
140 void free_iova_mem(struct iova *iova);
141 void free_iova(struct iova_domain *iovad, unsigned long pfn);
142 void __free_iova(struct iova_domain *iovad, struct iova *iova);
143 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
144 	unsigned long limit_pfn,
145 	bool size_aligned);
146 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
147 		    unsigned long size);
148 void queue_iova(struct iova_domain *iovad,
149 		unsigned long pfn, unsigned long pages,
150 		unsigned long data);
151 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
152 			      unsigned long limit_pfn, bool flush_rcache);
153 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
154 	unsigned long pfn_hi);
155 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
156 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
157 	unsigned long start_pfn);
158 int init_iova_flush_queue(struct iova_domain *iovad,
159 			  iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
160 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
161 void put_iova_domain(struct iova_domain *iovad);
162 struct iova *split_and_remove_iova(struct iova_domain *iovad,
163 	struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
164 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
165 #else
166 static inline int iova_cache_get(void)
167 {
168 	return -ENOTSUPP;
169 }
170 
171 static inline void iova_cache_put(void)
172 {
173 }
174 
175 static inline struct iova *alloc_iova_mem(void)
176 {
177 	return NULL;
178 }
179 
180 static inline void free_iova_mem(struct iova *iova)
181 {
182 }
183 
184 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
185 {
186 }
187 
188 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
189 {
190 }
191 
192 static inline struct iova *alloc_iova(struct iova_domain *iovad,
193 				      unsigned long size,
194 				      unsigned long limit_pfn,
195 				      bool size_aligned)
196 {
197 	return NULL;
198 }
199 
200 static inline void free_iova_fast(struct iova_domain *iovad,
201 				  unsigned long pfn,
202 				  unsigned long size)
203 {
204 }
205 
206 static inline void queue_iova(struct iova_domain *iovad,
207 			      unsigned long pfn, unsigned long pages,
208 			      unsigned long data)
209 {
210 }
211 
212 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
213 					    unsigned long size,
214 					    unsigned long limit_pfn,
215 					    bool flush_rcache)
216 {
217 	return 0;
218 }
219 
220 static inline struct iova *reserve_iova(struct iova_domain *iovad,
221 					unsigned long pfn_lo,
222 					unsigned long pfn_hi)
223 {
224 	return NULL;
225 }
226 
227 static inline void copy_reserved_iova(struct iova_domain *from,
228 				      struct iova_domain *to)
229 {
230 }
231 
232 static inline void init_iova_domain(struct iova_domain *iovad,
233 				    unsigned long granule,
234 				    unsigned long start_pfn)
235 {
236 }
237 
238 static inline int init_iova_flush_queue(struct iova_domain *iovad,
239 					iova_flush_cb flush_cb,
240 					iova_entry_dtor entry_dtor)
241 {
242 	return -ENODEV;
243 }
244 
245 static inline struct iova *find_iova(struct iova_domain *iovad,
246 				     unsigned long pfn)
247 {
248 	return NULL;
249 }
250 
251 static inline void put_iova_domain(struct iova_domain *iovad)
252 {
253 }
254 
255 static inline struct iova *split_and_remove_iova(struct iova_domain *iovad,
256 						 struct iova *iova,
257 						 unsigned long pfn_lo,
258 						 unsigned long pfn_hi)
259 {
260 	return NULL;
261 }
262 
263 static inline void free_cpu_cached_iovas(unsigned int cpu,
264 					 struct iova_domain *iovad)
265 {
266 }
267 #endif
268 
269 #endif
270