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 */
18struct 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
25struct iova_rcache;
26
27/* holds all the iova translations for a domain */
28struct 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
43static inline unsigned long iova_size(struct iova *iova)
44{
45	return iova->pfn_hi - iova->pfn_lo + 1;
46}
47
48static inline unsigned long iova_shift(struct iova_domain *iovad)
49{
50	return __ffs(iovad->granule);
51}
52
53static inline unsigned long iova_mask(struct iova_domain *iovad)
54{
55	return iovad->granule - 1;
56}
57
58static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
59{
60	return iova & iova_mask(iovad);
61}
62
63static inline size_t iova_align(struct iova_domain *iovad, size_t size)
64{
65	return ALIGN(size, iovad->granule);
66}
67
68static inline size_t iova_align_down(struct iova_domain *iovad, size_t size)
69{
70	return ALIGN_DOWN(size, iovad->granule);
71}
72
73static 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
78static 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)
84int iova_cache_get(void);
85void iova_cache_put(void);
86
87unsigned long iova_rcache_range(void);
88
89void free_iova(struct iova_domain *iovad, unsigned long pfn);
90void __free_iova(struct iova_domain *iovad, struct iova *iova);
91struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
92	unsigned long limit_pfn,
93	bool size_aligned);
94void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
95		    unsigned long size);
96unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
97			      unsigned long limit_pfn, bool flush_rcache);
98struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
99	unsigned long pfn_hi);
100void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
101	unsigned long start_pfn);
102int iova_domain_init_rcaches(struct iova_domain *iovad);
103struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
104void put_iova_domain(struct iova_domain *iovad);
105#else
106static inline int iova_cache_get(void)
107{
108	return -ENOTSUPP;
109}
110
111static inline void iova_cache_put(void)
112{
113}
114
115static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
116{
117}
118
119static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
120{
121}
122
123static 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
131static inline void free_iova_fast(struct iova_domain *iovad,
132				  unsigned long pfn,
133				  unsigned long size)
134{
135}
136
137static 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
145static 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
152static inline void init_iova_domain(struct iova_domain *iovad,
153				    unsigned long granule,
154				    unsigned long start_pfn)
155{
156}
157
158static inline struct iova *find_iova(struct iova_domain *iovad,
159				     unsigned long pfn)
160{
161	return NULL;
162}
163
164static inline void put_iova_domain(struct iova_domain *iovad)
165{
166}
167
168#endif
169
170#endif
171