xref: /linux-6.15/include/linux/iova.h (revision f96cffd7)
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/dma-mapping.h>
18 
19 /* iova structure */
20 struct iova {
21 	struct rb_node	node;
22 	unsigned long	pfn_hi; /* Highest allocated pfn */
23 	unsigned long	pfn_lo; /* Lowest allocated pfn */
24 };
25 
26 struct iova_magazine;
27 struct iova_cpu_rcache;
28 
29 #define IOVA_RANGE_CACHE_MAX_SIZE 6	/* log of max cached IOVA range size (in pages) */
30 #define MAX_GLOBAL_MAGS 32	/* magazines per bin */
31 
32 struct iova_rcache {
33 	spinlock_t lock;
34 	unsigned long depot_size;
35 	struct iova_magazine *depot[MAX_GLOBAL_MAGS];
36 	struct iova_cpu_rcache __percpu *cpu_rcaches;
37 };
38 
39 /* holds all the iova translations for a domain */
40 struct iova_domain {
41 	spinlock_t	iova_rbtree_lock; /* Lock to protect update of rbtree */
42 	struct rb_root	rbroot;		/* iova domain rbtree root */
43 	struct rb_node	*cached32_node; /* Save last alloced node */
44 	unsigned long	granule;	/* pfn granularity for this domain */
45 	unsigned long	start_pfn;	/* Lower limit for this domain */
46 	unsigned long	dma_32bit_pfn;
47 	struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];	/* IOVA range caches */
48 };
49 
50 static inline unsigned long iova_size(struct iova *iova)
51 {
52 	return iova->pfn_hi - iova->pfn_lo + 1;
53 }
54 
55 static inline unsigned long iova_shift(struct iova_domain *iovad)
56 {
57 	return __ffs(iovad->granule);
58 }
59 
60 static inline unsigned long iova_mask(struct iova_domain *iovad)
61 {
62 	return iovad->granule - 1;
63 }
64 
65 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
66 {
67 	return iova & iova_mask(iovad);
68 }
69 
70 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
71 {
72 	return ALIGN(size, iovad->granule);
73 }
74 
75 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
76 {
77 	return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
78 }
79 
80 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
81 {
82 	return iova >> iova_shift(iovad);
83 }
84 
85 int iova_cache_get(void);
86 void iova_cache_put(void);
87 
88 struct iova *alloc_iova_mem(void);
89 void free_iova_mem(struct iova *iova);
90 void free_iova(struct iova_domain *iovad, unsigned long pfn);
91 void __free_iova(struct iova_domain *iovad, struct iova *iova);
92 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
93 	unsigned long limit_pfn,
94 	bool size_aligned);
95 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
96 		    unsigned long size);
97 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
98 			      unsigned long limit_pfn);
99 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
100 	unsigned long pfn_hi);
101 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
102 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
103 	unsigned long start_pfn, unsigned long pfn_32bit);
104 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
105 void put_iova_domain(struct iova_domain *iovad);
106 struct iova *split_and_remove_iova(struct iova_domain *iovad,
107 	struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
108 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
109 
110 #endif
111