1/****************************************************************************** 2 * gntdev.h 3 * 4 * Interface to /dev/xen/gntdev. 5 * 6 * Copyright (c) 2007, D G Murray 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License version 2 10 * as published by the Free Software Foundation; or, when distributed 11 * separately from the Linux kernel or incorporated into other 12 * software packages, subject to the following license: 13 * 14 * Permission is hereby granted, free of charge, to any person obtaining a copy 15 * of this source file (the "Software"), to deal in the Software without 16 * restriction, including without limitation the rights to use, copy, modify, 17 * merge, publish, distribute, sublicense, and/or sell copies of the Software, 18 * and to permit persons to whom the Software is furnished to do so, subject to 19 * the following conditions: 20 * 21 * The above copyright notice and this permission notice shall be included in 22 * all copies or substantial portions of the Software. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 25 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 26 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 27 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 28 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 29 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 30 * IN THE SOFTWARE. 31 */ 32 33#ifndef __XEN_GNTDEV_H__ 34#define __XEN_GNTDEV_H__ 35 36#include <sys/ioccom.h> 37 38struct ioctl_gntdev_grant_ref { 39 /* The domain ID of the grant to be mapped. */ 40 uint32_t domid; 41 /* The grant reference of the grant to be mapped. */ 42 uint32_t ref; 43}; 44 45/* 46 * Inserts the grant references into the mapping table of an instance 47 * of gntdev. N.B. This does not perform the mapping, which is deferred 48 * until mmap() is called with @index as the offset. 49 */ 50#define IOCTL_GNTDEV_MAP_GRANT_REF \ 51 _IOWR('G', 0, sizeof(struct ioctl_gntdev_map_grant_ref)) 52struct ioctl_gntdev_map_grant_ref { 53 /* IN parameters */ 54 /* The number of grants to be mapped. */ 55 uint32_t count; 56 uint32_t pad; 57 /* OUT parameters */ 58 /* The offset to be used on a subsequent call to mmap(). */ 59 uint64_t index; 60 /* Variable IN parameter. */ 61 /* Array of grant references, of size @count. */ 62 struct ioctl_gntdev_grant_ref refs[1]; 63}; 64 65/* 66 * Removes the grant references from the mapping table of an instance of 67 * of gntdev. N.B. munmap() must be called on the relevant virtual address(es) 68 * before this ioctl is called, or an error will result. 69 */ 70#define IOCTL_GNTDEV_UNMAP_GRANT_REF \ 71 _IOW('G', 1, sizeof(struct ioctl_gntdev_unmap_grant_ref)) 72struct ioctl_gntdev_unmap_grant_ref { 73 /* IN parameters */ 74 /* The offset was returned by the corresponding map operation. */ 75 uint64_t index; 76 /* The number of pages to be unmapped. */ 77 uint32_t count; 78 uint32_t pad; 79}; 80 81/* 82 * Returns the offset in the driver's address space that corresponds 83 * to @vaddr. This can be used to perform a munmap(), followed by an 84 * UNMAP_GRANT_REF ioctl, where no state about the offset is retained by 85 * the caller. The number of pages that were allocated at the same time as 86 * @vaddr is returned in @count. 87 * 88 * N.B. Where more than one page has been mapped into a contiguous range, the 89 * supplied @vaddr must correspond to the start of the range; otherwise 90 * an error will result. It is only possible to munmap() the entire 91 * contiguously-allocated range at once, and not any subrange thereof. 92 */ 93#define IOCTL_GNTDEV_GET_OFFSET_FOR_VADDR \ 94 _IOWR('G', 2, sizeof(struct ioctl_gntdev_get_offset_for_vaddr)) 95struct ioctl_gntdev_get_offset_for_vaddr { 96 /* IN parameters */ 97 /* The virtual address of the first mapped page in a range. */ 98 uint64_t vaddr; 99 /* OUT parameters */ 100 /* The offset that was used in the initial mmap() operation. */ 101 uint64_t offset; 102 /* The number of pages mapped in the VM area that begins at @vaddr. */ 103 uint32_t count; 104 uint32_t pad; 105}; 106 107/* 108 * Sets the maximum number of grants that may mapped at once by this gntdev 109 * instance. 110 * 111 * N.B. This must be called before any other ioctl is performed on the device. 112 */ 113#define IOCTL_GNTDEV_SET_MAX_GRANTS \ 114 _IOW('G', 3, sizeof(struct ioctl_gntdev_set_max_grants)) 115struct ioctl_gntdev_set_max_grants { 116 /* IN parameter */ 117 /* The maximum number of grants that may be mapped at once. */ 118 uint32_t count; 119}; 120 121#endif /* __XEN_GNTDEV_H__ */ 122