Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/*
2 * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
3 * Author: Joerg Roedel <joerg.roedel@amd.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published
7 * by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 */
18
19#ifndef __LINUX_IOMMU_H
20#define __LINUX_IOMMU_H
21
22#include <linux/errno.h>
23
24#define IOMMU_READ (1)
25#define IOMMU_WRITE (2)
26#define IOMMU_CACHE (4) /* DMA cache coherency */
27
28struct iommu_ops;
29struct bus_type;
30struct device;
31struct iommu_domain;
32
33/* iommu fault flags */
34#define IOMMU_FAULT_READ 0x0
35#define IOMMU_FAULT_WRITE 0x1
36
37typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
38 struct device *, unsigned long, int);
39
40struct iommu_domain {
41 struct iommu_ops *ops;
42 void *priv;
43 iommu_fault_handler_t handler;
44};
45
46#define IOMMU_CAP_CACHE_COHERENCY 0x1
47#define IOMMU_CAP_INTR_REMAP 0x2 /* isolates device intrs */
48
49#ifdef CONFIG_IOMMU_API
50
51struct iommu_ops {
52 int (*domain_init)(struct iommu_domain *domain);
53 void (*domain_destroy)(struct iommu_domain *domain);
54 int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
55 void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
56 int (*map)(struct iommu_domain *domain, unsigned long iova,
57 phys_addr_t paddr, int gfp_order, int prot);
58 int (*unmap)(struct iommu_domain *domain, unsigned long iova,
59 int gfp_order);
60 phys_addr_t (*iova_to_phys)(struct iommu_domain *domain,
61 unsigned long iova);
62 int (*domain_has_cap)(struct iommu_domain *domain,
63 unsigned long cap);
64};
65
66extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
67extern bool iommu_present(struct bus_type *bus);
68extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
69extern void iommu_domain_free(struct iommu_domain *domain);
70extern int iommu_attach_device(struct iommu_domain *domain,
71 struct device *dev);
72extern void iommu_detach_device(struct iommu_domain *domain,
73 struct device *dev);
74extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
75 phys_addr_t paddr, int gfp_order, int prot);
76extern int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
77 int gfp_order);
78extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
79 unsigned long iova);
80extern int iommu_domain_has_cap(struct iommu_domain *domain,
81 unsigned long cap);
82extern void iommu_set_fault_handler(struct iommu_domain *domain,
83 iommu_fault_handler_t handler);
84
85/**
86 * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
87 * @domain: the iommu domain where the fault has happened
88 * @dev: the device where the fault has happened
89 * @iova: the faulting address
90 * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
91 *
92 * This function should be called by the low-level IOMMU implementations
93 * whenever IOMMU faults happen, to allow high-level users, that are
94 * interested in such events, to know about them.
95 *
96 * This event may be useful for several possible use cases:
97 * - mere logging of the event
98 * - dynamic TLB/PTE loading
99 * - if restarting of the faulting device is required
100 *
101 * Returns 0 on success and an appropriate error code otherwise (if dynamic
102 * PTE/TLB loading will one day be supported, implementations will be able
103 * to tell whether it succeeded or not according to this return value).
104 *
105 * Specifically, -ENOSYS is returned if a fault handler isn't installed
106 * (though fault handlers can also return -ENOSYS, in case they want to
107 * elicit the default behavior of the IOMMU drivers).
108 */
109static inline int report_iommu_fault(struct iommu_domain *domain,
110 struct device *dev, unsigned long iova, int flags)
111{
112 int ret = -ENOSYS;
113
114 /*
115 * if upper layers showed interest and installed a fault handler,
116 * invoke it.
117 */
118 if (domain->handler)
119 ret = domain->handler(domain, dev, iova, flags);
120
121 return ret;
122}
123
124#else /* CONFIG_IOMMU_API */
125
126struct iommu_ops {};
127
128static inline bool iommu_present(struct bus_type *bus)
129{
130 return false;
131}
132
133static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
134{
135 return NULL;
136}
137
138static inline void iommu_domain_free(struct iommu_domain *domain)
139{
140}
141
142static inline int iommu_attach_device(struct iommu_domain *domain,
143 struct device *dev)
144{
145 return -ENODEV;
146}
147
148static inline void iommu_detach_device(struct iommu_domain *domain,
149 struct device *dev)
150{
151}
152
153static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
154 phys_addr_t paddr, int gfp_order, int prot)
155{
156 return -ENODEV;
157}
158
159static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
160 int gfp_order)
161{
162 return -ENODEV;
163}
164
165static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
166 unsigned long iova)
167{
168 return 0;
169}
170
171static inline int domain_has_cap(struct iommu_domain *domain,
172 unsigned long cap)
173{
174 return 0;
175}
176
177static inline void iommu_set_fault_handler(struct iommu_domain *domain,
178 iommu_fault_handler_t handler)
179{
180}
181
182#endif /* CONFIG_IOMMU_API */
183
184#endif /* __LINUX_IOMMU_H */