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
28 struct iommu_ops;
29 struct bus_type;
30 struct device;
31 struct iommu_domain;
32
33 /* iommu fault flags */
34 #define IOMMU_FAULT_READ 0x0
35 #define IOMMU_FAULT_WRITE 0x1
36
37 typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
38 struct device *, unsigned long, int);
39
40 struct 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
51 /**
52 * struct iommu_ops - iommu ops and capabilities
53 * @domain_init: init iommu domain
54 * @domain_destroy: destroy iommu domain
55 * @attach_dev: attach device to an iommu domain
56 * @detach_dev: detach device from an iommu domain
57 * @map: map a physically contiguous memory region to an iommu domain
58 * @unmap: unmap a physically contiguous memory region from an iommu domain
59 * @iova_to_phys: translate iova to physical address
60 * @domain_has_cap: domain capabilities query
61 * @commit: commit iommu domain
62 * @pgsize_bitmap: bitmap of supported page sizes
63 */
64 struct iommu_ops {
65 int (*domain_init)(struct iommu_domain *domain);
66 void (*domain_destroy)(struct iommu_domain *domain);
67 int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
68 void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
69 int (*map)(struct iommu_domain *domain, unsigned long iova,
70 phys_addr_t paddr, size_t size, int prot);
71 size_t (*unmap)(struct iommu_domain *domain, unsigned long iova,
72 size_t size);
73 phys_addr_t (*iova_to_phys)(struct iommu_domain *domain,
74 unsigned long iova);
75 int (*domain_has_cap)(struct iommu_domain *domain,
76 unsigned long cap);
77 int (*device_group)(struct device *dev, unsigned int *groupid);
78 unsigned long pgsize_bitmap;
79 };
80
81 extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
82 extern bool iommu_present(struct bus_type *bus);
83 extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
84 extern void iommu_domain_free(struct iommu_domain *domain);
85 extern int iommu_attach_device(struct iommu_domain *domain,
86 struct device *dev);
87 extern void iommu_detach_device(struct iommu_domain *domain,
88 struct device *dev);
89 extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
90 phys_addr_t paddr, size_t size, int prot);
91 extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
92 size_t size);
93 extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
94 unsigned long iova);
95 extern int iommu_domain_has_cap(struct iommu_domain *domain,
96 unsigned long cap);
97 extern void iommu_set_fault_handler(struct iommu_domain *domain,
98 iommu_fault_handler_t handler);
99 extern int iommu_device_group(struct device *dev, unsigned int *groupid);
100
101 /**
102 * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
103 * @domain: the iommu domain where the fault has happened
104 * @dev: the device where the fault has happened
105 * @iova: the faulting address
106 * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
107 *
108 * This function should be called by the low-level IOMMU implementations
109 * whenever IOMMU faults happen, to allow high-level users, that are
110 * interested in such events, to know about them.
111 *
112 * This event may be useful for several possible use cases:
113 * - mere logging of the event
114 * - dynamic TLB/PTE loading
115 * - if restarting of the faulting device is required
116 *
117 * Returns 0 on success and an appropriate error code otherwise (if dynamic
118 * PTE/TLB loading will one day be supported, implementations will be able
119 * to tell whether it succeeded or not according to this return value).
120 *
121 * Specifically, -ENOSYS is returned if a fault handler isn't installed
122 * (though fault handlers can also return -ENOSYS, in case they want to
123 * elicit the default behavior of the IOMMU drivers).
124 */
report_iommu_fault(struct iommu_domain * domain,struct device * dev,unsigned long iova,int flags)125 static inline int report_iommu_fault(struct iommu_domain *domain,
126 struct device *dev, unsigned long iova, int flags)
127 {
128 int ret = -ENOSYS;
129
130 /*
131 * if upper layers showed interest and installed a fault handler,
132 * invoke it.
133 */
134 if (domain->handler)
135 ret = domain->handler(domain, dev, iova, flags);
136
137 return ret;
138 }
139
140 #else /* CONFIG_IOMMU_API */
141
142 struct iommu_ops {};
143
iommu_present(struct bus_type * bus)144 static inline bool iommu_present(struct bus_type *bus)
145 {
146 return false;
147 }
148
iommu_domain_alloc(struct bus_type * bus)149 static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
150 {
151 return NULL;
152 }
153
iommu_domain_free(struct iommu_domain * domain)154 static inline void iommu_domain_free(struct iommu_domain *domain)
155 {
156 }
157
iommu_attach_device(struct iommu_domain * domain,struct device * dev)158 static inline int iommu_attach_device(struct iommu_domain *domain,
159 struct device *dev)
160 {
161 return -ENODEV;
162 }
163
iommu_detach_device(struct iommu_domain * domain,struct device * dev)164 static inline void iommu_detach_device(struct iommu_domain *domain,
165 struct device *dev)
166 {
167 }
168
iommu_map(struct iommu_domain * domain,unsigned long iova,phys_addr_t paddr,int gfp_order,int prot)169 static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
170 phys_addr_t paddr, int gfp_order, int prot)
171 {
172 return -ENODEV;
173 }
174
iommu_unmap(struct iommu_domain * domain,unsigned long iova,int gfp_order)175 static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
176 int gfp_order)
177 {
178 return -ENODEV;
179 }
180
iommu_iova_to_phys(struct iommu_domain * domain,unsigned long iova)181 static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
182 unsigned long iova)
183 {
184 return 0;
185 }
186
domain_has_cap(struct iommu_domain * domain,unsigned long cap)187 static inline int domain_has_cap(struct iommu_domain *domain,
188 unsigned long cap)
189 {
190 return 0;
191 }
192
iommu_set_fault_handler(struct iommu_domain * domain,iommu_fault_handler_t handler)193 static inline void iommu_set_fault_handler(struct iommu_domain *domain,
194 iommu_fault_handler_t handler)
195 {
196 }
197
iommu_device_group(struct device * dev,unsigned int * groupid)198 static inline int iommu_device_group(struct device *dev, unsigned int *groupid)
199 {
200 return -ENODEV;
201 }
202
203 #endif /* CONFIG_IOMMU_API */
204
205 #endif /* __LINUX_IOMMU_H */
206