page_track.c (4776B)
1/* 2 * Copyright(c) 2011-2017 Intel Corporation. All rights reserved. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 * SOFTWARE. 22 */ 23#include "i915_drv.h" 24#include "gvt.h" 25 26/** 27 * intel_vgpu_find_page_track - find page track rcord of guest page 28 * @vgpu: a vGPU 29 * @gfn: the gfn of guest page 30 * 31 * Returns: 32 * A pointer to struct intel_vgpu_page_track if found, else NULL returned. 33 */ 34struct intel_vgpu_page_track *intel_vgpu_find_page_track( 35 struct intel_vgpu *vgpu, unsigned long gfn) 36{ 37 return radix_tree_lookup(&vgpu->page_track_tree, gfn); 38} 39 40/** 41 * intel_vgpu_register_page_track - register a guest page to be tacked 42 * @vgpu: a vGPU 43 * @gfn: the gfn of guest page 44 * @handler: page track handler 45 * @priv: tracker private 46 * 47 * Returns: 48 * zero on success, negative error code if failed. 49 */ 50int intel_vgpu_register_page_track(struct intel_vgpu *vgpu, unsigned long gfn, 51 gvt_page_track_handler_t handler, void *priv) 52{ 53 struct intel_vgpu_page_track *track; 54 int ret; 55 56 track = intel_vgpu_find_page_track(vgpu, gfn); 57 if (track) 58 return -EEXIST; 59 60 track = kzalloc(sizeof(*track), GFP_KERNEL); 61 if (!track) 62 return -ENOMEM; 63 64 track->handler = handler; 65 track->priv_data = priv; 66 67 ret = radix_tree_insert(&vgpu->page_track_tree, gfn, track); 68 if (ret) { 69 kfree(track); 70 return ret; 71 } 72 73 return 0; 74} 75 76/** 77 * intel_vgpu_unregister_page_track - unregister the tracked guest page 78 * @vgpu: a vGPU 79 * @gfn: the gfn of guest page 80 * 81 */ 82void intel_vgpu_unregister_page_track(struct intel_vgpu *vgpu, 83 unsigned long gfn) 84{ 85 struct intel_vgpu_page_track *track; 86 87 track = radix_tree_delete(&vgpu->page_track_tree, gfn); 88 if (track) { 89 if (track->tracked) 90 intel_gvt_page_track_remove(vgpu, gfn); 91 kfree(track); 92 } 93} 94 95/** 96 * intel_vgpu_enable_page_track - set write-protection on guest page 97 * @vgpu: a vGPU 98 * @gfn: the gfn of guest page 99 * 100 * Returns: 101 * zero on success, negative error code if failed. 102 */ 103int intel_vgpu_enable_page_track(struct intel_vgpu *vgpu, unsigned long gfn) 104{ 105 struct intel_vgpu_page_track *track; 106 int ret; 107 108 track = intel_vgpu_find_page_track(vgpu, gfn); 109 if (!track) 110 return -ENXIO; 111 112 if (track->tracked) 113 return 0; 114 115 ret = intel_gvt_page_track_add(vgpu, gfn); 116 if (ret) 117 return ret; 118 track->tracked = true; 119 return 0; 120} 121 122/** 123 * intel_vgpu_enable_page_track - cancel write-protection on guest page 124 * @vgpu: a vGPU 125 * @gfn: the gfn of guest page 126 * 127 * Returns: 128 * zero on success, negative error code if failed. 129 */ 130int intel_vgpu_disable_page_track(struct intel_vgpu *vgpu, unsigned long gfn) 131{ 132 struct intel_vgpu_page_track *track; 133 int ret; 134 135 track = intel_vgpu_find_page_track(vgpu, gfn); 136 if (!track) 137 return -ENXIO; 138 139 if (!track->tracked) 140 return 0; 141 142 ret = intel_gvt_page_track_remove(vgpu, gfn); 143 if (ret) 144 return ret; 145 track->tracked = false; 146 return 0; 147} 148 149/** 150 * intel_vgpu_page_track_handler - called when write to write-protected page 151 * @vgpu: a vGPU 152 * @gpa: the gpa of this write 153 * @data: the writed data 154 * @bytes: the length of this write 155 * 156 * Returns: 157 * zero on success, negative error code if failed. 158 */ 159int intel_vgpu_page_track_handler(struct intel_vgpu *vgpu, u64 gpa, 160 void *data, unsigned int bytes) 161{ 162 struct intel_vgpu_page_track *page_track; 163 int ret = 0; 164 165 mutex_lock(&vgpu->vgpu_lock); 166 167 page_track = intel_vgpu_find_page_track(vgpu, gpa >> PAGE_SHIFT); 168 if (!page_track) { 169 ret = -ENXIO; 170 goto out; 171 } 172 173 if (unlikely(vgpu->failsafe)) { 174 /* Remove write protection to prevent furture traps. */ 175 intel_gvt_page_track_remove(vgpu, gpa >> PAGE_SHIFT); 176 } else { 177 ret = page_track->handler(page_track, gpa, data, bytes); 178 if (ret) 179 gvt_err("guest page write error, gpa %llx\n", gpa); 180 } 181 182out: 183 mutex_unlock(&vgpu->vgpu_lock); 184 return ret; 185}