xref: /dragonfly/sys/dev/drm/drm_vm.c (revision 926deccb)
1 /*-
2  * Copyright 2003 Eric Anholt
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * ERIC ANHOLT BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
20  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22  *
23  * $FreeBSD: head/sys/dev/drm2/drm_vm.c 235783 2012-05-22 11:07:44Z kib $"
24  */
25 
26 /** @file drm_vm.c
27  * Support code for mmaping of DRM maps.
28  */
29 
30 #include <sys/conf.h>
31 #include <sys/mutex2.h>
32 #include <vm/vm_page.h>
33 #include <vm/vm_pager.h>
34 
35 #include <drm/drmP.h>
36 
37 int drm_mmap(struct dev_mmap_args *ap)
38 {
39 	struct cdev *kdev = ap->a_head.a_dev;
40 	vm_offset_t offset = ap->a_offset;
41 	struct drm_device *dev = drm_get_device_from_kdev(kdev);
42 	struct drm_file *file_priv = NULL;
43 	struct drm_local_map *map = NULL;
44 	struct drm_map_list *r_list;
45 
46 	enum drm_map_type type;
47 	vm_paddr_t phys;
48 
49 	/* d_mmap gets called twice, we can only reference file_priv during
50 	 * the first call.  We need to assume that if error is EBADF the
51 	 * call was succesful and the client is authenticated.
52 	 */
53 	DRM_LOCK(dev);
54 	file_priv = drm_find_file_by_proc(dev, curthread);
55 	DRM_UNLOCK(dev);
56 
57 	if (!file_priv) {
58 		DRM_ERROR("Could not find authenticator!\n");
59 		return EINVAL;
60 	}
61 
62 	if (!file_priv->authenticated)
63 		return EACCES;
64 
65 	DRM_DEBUG("called with offset %016jx\n", (uintmax_t)offset);
66 	if (dev->dma && offset < ptoa(dev->dma->page_count)) {
67 		drm_device_dma_t *dma = dev->dma;
68 
69 		spin_lock(&dev->dma_lock);
70 
71 		if (dma->pagelist != NULL) {
72 			unsigned long page = offset >> PAGE_SHIFT;
73 			unsigned long phys = dma->pagelist[page];
74 
75 			spin_unlock(&dev->dma_lock);
76 			// XXX *paddr = phys;
77 			ap->a_result = phys;
78 			return 0;
79 		} else {
80 			spin_unlock(&dev->dma_lock);
81 			return -1;
82 		}
83 	}
84 
85 	/* A sequential search of a linked list is
86 	   fine here because: 1) there will only be
87 	   about 5-10 entries in the list and, 2) a
88 	   DRI client only has to do this mapping
89 	   once, so it doesn't have to be optimized
90 	   for performance, even if the list was a
91 	   bit longer.
92 	*/
93 	DRM_LOCK(dev);
94 	list_for_each_entry(r_list, &dev->maplist, head) {
95 		if (r_list->map && r_list->map->offset >> DRM_MAP_HANDLE_SHIFT ==
96 		    (unsigned long)r_list->map->handle >> DRM_MAP_HANDLE_SHIFT)
97 			map = r_list->map;
98 			break;
99 	}
100 
101 	if (map == NULL) {
102 		DRM_DEBUG("Can't find map, request offset = %016jx\n",
103 		    (uintmax_t)offset);
104 		list_for_each_entry(r_list, &dev->maplist, head) {
105 			DRM_DEBUG("map offset = %016lx, handle = %016lx\n",
106 			    r_list->map->offset, (unsigned long)r_list->map->handle);
107 		}
108 		DRM_UNLOCK(dev);
109 		return -1;
110 	}
111 	if (((map->flags & _DRM_RESTRICTED) && !DRM_SUSER(DRM_CURPROC))) {
112 		DRM_UNLOCK(dev);
113 		DRM_DEBUG("restricted map\n");
114 		return -1;
115 	}
116 	type = map->type;
117 	DRM_UNLOCK(dev);
118 
119 	offset = offset & ((1ULL << DRM_MAP_HANDLE_SHIFT) - 1);
120 
121 	switch (type) {
122 	case _DRM_FRAME_BUFFER:
123 	case _DRM_AGP:
124 #if 0	/* XXX */
125 		*memattr = VM_MEMATTR_WRITE_COMBINING;
126 #endif
127 		/* FALLTHROUGH */
128 	case _DRM_REGISTERS:
129 		phys = map->offset + offset;
130 		break;
131 	case _DRM_SCATTER_GATHER:
132 #if 0	/* XXX */
133 		*memattr = VM_MEMATTR_WRITE_COMBINING;
134 #endif
135 		/* FALLTHROUGH */
136 	case _DRM_CONSISTENT:
137 	case _DRM_SHM:
138 		phys = vtophys((char *)map->virtual + offset);
139 		break;
140 	default:
141 		DRM_ERROR("bad map type %d\n", type);
142 		return -1;	/* This should never happen. */
143 	}
144 
145 	ap->a_result = atop(phys);
146 	return 0;
147 }
148 
149 /* XXX The following is just temporary hack to replace the
150  * vm_phys_fictitious functions available on FreeBSD
151  */
152 #define VM_PHYS_FICTITIOUS_NSEGS        8
153 static struct vm_phys_fictitious_seg {
154         vm_paddr_t      start;
155         vm_paddr_t      end;
156         vm_page_t       first_page;
157 } vm_phys_fictitious_segs[VM_PHYS_FICTITIOUS_NSEGS];
158 static struct mtx vm_phys_fictitious_reg_mtx = MTX_INITIALIZER;
159 
160 MALLOC_DEFINE(M_FICT_PAGES, "", "");
161 
162 vm_page_t
163 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
164 {
165         struct vm_phys_fictitious_seg *seg;
166         vm_page_t m;
167         int segind;
168 
169         m = NULL;
170         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
171                 seg = &vm_phys_fictitious_segs[segind];
172                 if (pa >= seg->start && pa < seg->end) {
173                         m = &seg->first_page[atop(pa - seg->start)];
174                         KASSERT((m->flags & PG_FICTITIOUS) != 0,
175                             ("%p not fictitious", m));
176                         break;
177                 }
178         }
179         return (m);
180 }
181 
182 int
183 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
184     vm_memattr_t memattr)
185 {
186         struct vm_phys_fictitious_seg *seg;
187         vm_page_t fp;
188         long i, page_count;
189         int segind;
190 
191         page_count = (end - start) / PAGE_SIZE;
192 
193         fp = kmalloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
194                     M_WAITOK | M_ZERO);
195 
196         for (i = 0; i < page_count; i++) {
197 		vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr);
198 		fp[i].flags &= ~(PG_BUSY | PG_UNMANAGED);
199         }
200         mtx_lock(&vm_phys_fictitious_reg_mtx);
201         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
202                 seg = &vm_phys_fictitious_segs[segind];
203                 if (seg->start == 0 && seg->end == 0) {
204                         seg->start = start;
205                         seg->end = end;
206                         seg->first_page = fp;
207                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
208                         return (0);
209                 }
210         }
211         mtx_unlock(&vm_phys_fictitious_reg_mtx);
212         kfree(fp, M_FICT_PAGES);
213         return (EBUSY);
214 }
215 
216 void
217 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
218 {
219 	struct vm_phys_fictitious_seg *seg;
220 	vm_page_t fp;
221 	int segind;
222 
223 	mtx_lock(&vm_phys_fictitious_reg_mtx);
224 	for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
225 		seg = &vm_phys_fictitious_segs[segind];
226 		if (seg->start == start && seg->end == end) {
227 			seg->start = seg->end = 0;
228 			fp = seg->first_page;
229 			seg->first_page = NULL;
230 			mtx_unlock(&vm_phys_fictitious_reg_mtx);
231 			kfree(fp, M_FICT_PAGES);
232 			return;
233 		}
234 	}
235 	mtx_unlock(&vm_phys_fictitious_reg_mtx);
236 	KASSERT(0, ("Unregistering not registered fictitious range"));
237 }
238