drm_vm.c revision 1.8
1 /* $NetBSD: drm_vm.c,v 1.8 2018/08/27 06:58:20 riastradh Exp $ */ 2 3 /*- 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Taylor R. Campbell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: drm_vm.c,v 1.8 2018/08/27 06:58:20 riastradh Exp $"); 34 35 #include <sys/types.h> 36 #include <sys/conf.h> 37 38 #include <uvm/uvm_extern.h> 39 #include <uvm/uvm_device.h> 40 41 #include <drm/drmP.h> 42 #include <drm/drm_legacy.h> 43 44 static paddr_t drm_mmap_paddr_locked(struct drm_device *, off_t, int); 45 static paddr_t drm_mmap_dma_paddr(struct drm_device *, off_t, int); 46 static paddr_t drm_mmap_map_paddr(struct drm_device *, struct drm_local_map *, 47 off_t, int); 48 49 int 50 drm_mmap_object(struct drm_device *dev, off_t offset, size_t size, int prot, 51 struct uvm_object **uobjp, voff_t *uoffsetp, struct file *file __unused) 52 { 53 devmajor_t maj = cdevsw_lookup_major(&drm_cdevsw); 54 dev_t devno = makedev(maj, dev->primary->index); 55 struct uvm_object *uobj; 56 57 KASSERT(offset == (offset & ~(PAGE_SIZE-1))); 58 59 /* 60 * Attach the device. The size and offset are used only for 61 * access checks; offset does not become a base address for the 62 * subsequent uvm_map, hence we set *uoffsetp to offset, not 0. 63 */ 64 uobj = udv_attach(devno, prot, offset, size); 65 if (uobj == NULL) 66 return -EINVAL; 67 68 *uobjp = uobj; 69 *uoffsetp = offset; 70 return 0; 71 } 72 73 paddr_t 74 drm_mmap_paddr(struct drm_device *dev, off_t byte_offset, int prot) 75 { 76 paddr_t paddr; 77 78 if (byte_offset != (byte_offset & ~(PAGE_SIZE-1))) 79 return -1; 80 81 mutex_lock(&dev->struct_mutex); 82 paddr = drm_mmap_paddr_locked(dev, byte_offset, prot); 83 mutex_unlock(&dev->struct_mutex); 84 85 return paddr; 86 } 87 88 static paddr_t 89 drm_mmap_paddr_locked(struct drm_device *dev, off_t byte_offset, int prot) 90 { 91 const off_t page_offset = (byte_offset >> PAGE_SHIFT); 92 struct drm_hash_item *hash; 93 94 KASSERT(mutex_is_locked(&dev->struct_mutex)); 95 KASSERT(byte_offset == (byte_offset & ~(PAGE_SIZE-1))); 96 97 if ((dev->dma != NULL) && 98 (0 <= byte_offset) && 99 (page_offset <= dev->dma->page_count)) 100 return drm_mmap_dma_paddr(dev, byte_offset, prot); 101 102 if (drm_ht_find_item(&dev->map_hash, page_offset, &hash)) 103 return -1; 104 105 struct drm_local_map *const map = drm_hash_entry(hash, 106 struct drm_map_list, hash)->map; 107 if (map == NULL) 108 return -1; 109 110 /* 111 * XXX FreeBSD drops the mutex at this point, which would be 112 * nice, to allow sleeping in bus_dma cruft, but I don't know 113 * what guarantees the map will continue to exist. 114 */ 115 116 if (ISSET(map->flags, _DRM_RESTRICTED) && !DRM_SUSER()) 117 return -1; 118 119 if (!(map->offset <= byte_offset)) 120 return -1; 121 if (map->size < (map->offset - byte_offset)) 122 return -1; 123 124 return drm_mmap_map_paddr(dev, map, (byte_offset - map->offset), prot); 125 } 126 127 static paddr_t 128 drm_mmap_dma_paddr(struct drm_device *dev, off_t byte_offset, int prot) 129 { 130 const off_t page_offset = (byte_offset >> PAGE_SHIFT); 131 132 KASSERT(mutex_is_locked(&dev->struct_mutex)); 133 KASSERT(byte_offset == (byte_offset & ~(PAGE_SIZE-1))); 134 KASSERT(page_offset <= dev->dma->page_count); 135 136 if (dev->dma->pagelist == NULL) 137 return (paddr_t)-1; 138 139 return dev->dma->pagelist[page_offset]; 140 } 141 142 static paddr_t 143 drm_mmap_map_paddr(struct drm_device *dev, struct drm_local_map *map, 144 off_t byte_offset, int prot) 145 { 146 int flags = 0; 147 148 KASSERT(byte_offset <= map->size); 149 150 switch (map->type) { 151 case _DRM_FRAME_BUFFER: 152 case _DRM_AGP: 153 flags |= BUS_SPACE_MAP_PREFETCHABLE; 154 /* Fall through. */ 155 156 case _DRM_REGISTERS: 157 flags |= BUS_SPACE_MAP_LINEAR; /* XXX Why? */ 158 159 return bus_space_mmap(map->lm_data.bus_space.bst, map->offset, 160 byte_offset, prot, flags); 161 162 case _DRM_CONSISTENT: { 163 struct drm_dma_handle *const dmah = map->lm_data.dmah; 164 165 return bus_dmamem_mmap(dev->dmat, &dmah->dmah_seg, 1, 166 byte_offset, prot, 167 /* XXX BUS_DMA_WAITOK? We're holding a mutex... */ 168 /* XXX What else? BUS_DMA_COHERENT? */ 169 (BUS_DMA_WAITOK | BUS_DMA_NOCACHE)); 170 } 171 172 case _DRM_SCATTER_GATHER: { 173 struct drm_sg_mem *const sg = dev->sg; 174 175 #if 0 /* XXX */ 176 KASSERT(sg == map->lm_data.sg); 177 #endif 178 179 return bus_dmamem_mmap(dev->dmat, sg->sg_segs, sg->sg_nsegs, 180 byte_offset, prot, 181 /* XXX BUS_DMA_WAITOK? We're holding a mutex... */ 182 /* XXX What else? BUS_DMA_COHERENT? */ 183 (BUS_DMA_WAITOK | BUS_DMA_NOCACHE)); 184 } 185 186 case _DRM_SHM: 187 default: 188 return (paddr_t)-1; 189 } 190 } 191
Indexes created Thu Sep 25 16:09:42 GMT 2025