Linux kernel mirror (for testing)
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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, void *);
39
40struct iommu_domain {
41 struct iommu_ops *ops;
42 void *priv;
43 iommu_fault_handler_t handler;
44 void *handler_token;
45};
46
47#define IOMMU_CAP_CACHE_COHERENCY 0x1
48#define IOMMU_CAP_INTR_REMAP 0x2 /* isolates device intrs */
49
50#ifdef CONFIG_IOMMU_API
51
52/**
53 * struct iommu_ops - iommu ops and capabilities
54 * @domain_init: init iommu domain
55 * @domain_destroy: destroy iommu domain
56 * @attach_dev: attach device to an iommu domain
57 * @detach_dev: detach device from an iommu domain
58 * @map: map a physically contiguous memory region to an iommu domain
59 * @unmap: unmap a physically contiguous memory region from an iommu domain
60 * @iova_to_phys: translate iova to physical address
61 * @domain_has_cap: domain capabilities query
62 * @commit: commit iommu domain
63 * @pgsize_bitmap: bitmap of supported page sizes
64 */
65struct iommu_ops {
66 int (*domain_init)(struct iommu_domain *domain);
67 void (*domain_destroy)(struct iommu_domain *domain);
68 int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
69 void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
70 int (*map)(struct iommu_domain *domain, unsigned long iova,
71 phys_addr_t paddr, size_t size, int prot);
72 size_t (*unmap)(struct iommu_domain *domain, unsigned long iova,
73 size_t size);
74 phys_addr_t (*iova_to_phys)(struct iommu_domain *domain,
75 unsigned long iova);
76 int (*domain_has_cap)(struct iommu_domain *domain,
77 unsigned long cap);
78 int (*device_group)(struct device *dev, unsigned int *groupid);
79 unsigned long pgsize_bitmap;
80};
81
82extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
83extern bool iommu_present(struct bus_type *bus);
84extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
85extern void iommu_domain_free(struct iommu_domain *domain);
86extern int iommu_attach_device(struct iommu_domain *domain,
87 struct device *dev);
88extern void iommu_detach_device(struct iommu_domain *domain,
89 struct device *dev);
90extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
91 phys_addr_t paddr, size_t size, int prot);
92extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
93 size_t size);
94extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
95 unsigned long iova);
96extern int iommu_domain_has_cap(struct iommu_domain *domain,
97 unsigned long cap);
98extern void iommu_set_fault_handler(struct iommu_domain *domain,
99 iommu_fault_handler_t handler, void *token);
100extern int iommu_device_group(struct device *dev, unsigned int *groupid);
101
102/**
103 * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
104 * @domain: the iommu domain where the fault has happened
105 * @dev: the device where the fault has happened
106 * @iova: the faulting address
107 * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
108 *
109 * This function should be called by the low-level IOMMU implementations
110 * whenever IOMMU faults happen, to allow high-level users, that are
111 * interested in such events, to know about them.
112 *
113 * This event may be useful for several possible use cases:
114 * - mere logging of the event
115 * - dynamic TLB/PTE loading
116 * - if restarting of the faulting device is required
117 *
118 * Returns 0 on success and an appropriate error code otherwise (if dynamic
119 * PTE/TLB loading will one day be supported, implementations will be able
120 * to tell whether it succeeded or not according to this return value).
121 *
122 * Specifically, -ENOSYS is returned if a fault handler isn't installed
123 * (though fault handlers can also return -ENOSYS, in case they want to
124 * elicit the default behavior of the IOMMU drivers).
125 */
126static inline int report_iommu_fault(struct iommu_domain *domain,
127 struct device *dev, unsigned long iova, int flags)
128{
129 int ret = -ENOSYS;
130
131 /*
132 * if upper layers showed interest and installed a fault handler,
133 * invoke it.
134 */
135 if (domain->handler)
136 ret = domain->handler(domain, dev, iova, flags,
137 domain->handler_token);
138
139 return ret;
140}
141
142#else /* CONFIG_IOMMU_API */
143
144struct iommu_ops {};
145
146static inline bool iommu_present(struct bus_type *bus)
147{
148 return false;
149}
150
151static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
152{
153 return NULL;
154}
155
156static inline void iommu_domain_free(struct iommu_domain *domain)
157{
158}
159
160static inline int iommu_attach_device(struct iommu_domain *domain,
161 struct device *dev)
162{
163 return -ENODEV;
164}
165
166static inline void iommu_detach_device(struct iommu_domain *domain,
167 struct device *dev)
168{
169}
170
171static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
172 phys_addr_t paddr, int gfp_order, int prot)
173{
174 return -ENODEV;
175}
176
177static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
178 int gfp_order)
179{
180 return -ENODEV;
181}
182
183static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
184 unsigned long iova)
185{
186 return 0;
187}
188
189static inline int domain_has_cap(struct iommu_domain *domain,
190 unsigned long cap)
191{
192 return 0;
193}
194
195static inline void iommu_set_fault_handler(struct iommu_domain *domain,
196 iommu_fault_handler_t handler, void *token)
197{
198}
199
200static inline int iommu_device_group(struct device *dev, unsigned int *groupid)
201{
202 return -ENODEV;
203}
204
205#endif /* CONFIG_IOMMU_API */
206
207#endif /* __LINUX_IOMMU_H */