1 /****************************************************************************** 2 * grant_table.h 3 * 4 * Two sets of functionality: 5 * 1. Granting foreign access to our memory reservation. 6 * 2. Accessing others' memory reservations via grant references. 7 * (i.e., mechanisms for both sender and recipient of grant references) 8 * 9 * Copyright (c) 2004-2005, K A Fraser 10 * Copyright (c) 2005, Christopher Clark 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License version 2 14 * as published by the Free Software Foundation; or, when distributed 15 * separately from the Linux kernel or incorporated into other 16 * software packages, subject to the following license: 17 * 18 * Permission is hereby granted, free of charge, to any person obtaining a copy 19 * of this source file (the "Software"), to deal in the Software without 20 * restriction, including without limitation the rights to use, copy, modify, 21 * merge, publish, distribute, sublicense, and/or sell copies of the Software, 22 * and to permit persons to whom the Software is furnished to do so, subject to 23 * the following conditions: 24 * 25 * The above copyright notice and this permission notice shall be included in 26 * all copies or substantial portions of the Software. 27 * 28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 29 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 30 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 31 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 32 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 33 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 34 * IN THE SOFTWARE. 35 */ 36 37 #ifndef __ASM_GNTTAB_H__ 38 #define __ASM_GNTTAB_H__ 39 40 #include <asm/page.h> 41 42 #include <xen/interface/xen.h> 43 #include <xen/interface/grant_table.h> 44 45 #include <asm/xen/hypervisor.h> 46 #include <asm/xen/grant_table.h> 47 48 #include <xen/features.h> 49 50 /* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */ 51 #define NR_GRANT_FRAMES 4 52 53 struct gnttab_free_callback { 54 struct gnttab_free_callback *next; 55 void (*fn)(void *); 56 void *arg; 57 u16 count; 58 }; 59 60 int gnttab_init(void); 61 int gnttab_suspend(void); 62 int gnttab_resume(void); 63 64 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame, 65 int readonly); 66 67 /* 68 * End access through the given grant reference, iff the grant entry is no 69 * longer in use. Return 1 if the grant entry was freed, 0 if it is still in 70 * use. 71 */ 72 int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly); 73 74 /* 75 * Eventually end access through the given grant reference, and once that 76 * access has been ended, free the given page too. Access will be ended 77 * immediately iff the grant entry is not in use, otherwise it will happen 78 * some time later. page may be 0, in which case no freeing will occur. 79 */ 80 void gnttab_end_foreign_access(grant_ref_t ref, int readonly, 81 unsigned long page); 82 83 int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn); 84 85 unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref); 86 unsigned long gnttab_end_foreign_transfer(grant_ref_t ref); 87 88 int gnttab_query_foreign_access(grant_ref_t ref); 89 90 /* 91 * operations on reserved batches of grant references 92 */ 93 int gnttab_alloc_grant_references(u16 count, grant_ref_t *pprivate_head); 94 95 void gnttab_free_grant_reference(grant_ref_t ref); 96 97 void gnttab_free_grant_references(grant_ref_t head); 98 99 int gnttab_empty_grant_references(const grant_ref_t *pprivate_head); 100 101 int gnttab_claim_grant_reference(grant_ref_t *pprivate_head); 102 103 void gnttab_release_grant_reference(grant_ref_t *private_head, 104 grant_ref_t release); 105 106 void gnttab_request_free_callback(struct gnttab_free_callback *callback, 107 void (*fn)(void *), void *arg, u16 count); 108 void gnttab_cancel_free_callback(struct gnttab_free_callback *callback); 109 110 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid, 111 unsigned long frame, int readonly); 112 113 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid, 114 unsigned long pfn); 115 116 static inline void 117 gnttab_set_map_op(struct gnttab_map_grant_ref *map, phys_addr_t addr, 118 uint32_t flags, grant_ref_t ref, domid_t domid) 119 { 120 if (flags & GNTMAP_contains_pte) 121 map->host_addr = addr; 122 else if (xen_feature(XENFEAT_auto_translated_physmap)) 123 map->host_addr = __pa(addr); 124 else 125 map->host_addr = addr; 126 127 map->flags = flags; 128 map->ref = ref; 129 map->dom = domid; 130 } 131 132 static inline void 133 gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr, 134 uint32_t flags, grant_handle_t handle) 135 { 136 if (flags & GNTMAP_contains_pte) 137 unmap->host_addr = addr; 138 else if (xen_feature(XENFEAT_auto_translated_physmap)) 139 unmap->host_addr = __pa(addr); 140 else 141 unmap->host_addr = addr; 142 143 unmap->handle = handle; 144 unmap->dev_bus_addr = 0; 145 } 146 147 int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes, 148 unsigned long max_nr_gframes, 149 struct grant_entry **__shared); 150 void arch_gnttab_unmap_shared(struct grant_entry *shared, 151 unsigned long nr_gframes); 152 153 extern unsigned long xen_hvm_resume_frames; 154 unsigned int gnttab_max_grant_frames(void); 155 156 #define gnttab_map_vaddr(map) ((void *)(map.host_virt_addr)) 157 158 int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, 159 struct page **pages, unsigned int count); 160 int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, 161 struct page **pages, unsigned int count); 162 163 #endif /* __ASM_GNTTAB_H__ */ 164