xref: /dflybsd-src/sys/dev/drm/drm_vm.c (revision 450f08dbfd98cded95c51be4079ef10f5adb3241)
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 "dev/drm/drmP.h"
36 #include "dev/drm/drm.h"
37 
38 int drm_mmap(struct dev_mmap_args *ap)
39 {
40 	struct cdev *kdev = ap->a_head.a_dev;
41 	vm_offset_t offset = ap->a_offset;
42 	struct drm_device *dev = drm_get_device_from_kdev(kdev);
43 	struct drm_file *file_priv = NULL;
44 	drm_local_map_t *map;
45 	enum drm_map_type type;
46 	vm_paddr_t phys;
47 
48 	/* d_mmap gets called twice, we can only reference file_priv during
49 	 * the first call.  We need to assume that if error is EBADF the
50 	 * call was succesful and the client is authenticated.
51 	 */
52 	DRM_LOCK(dev);
53 	file_priv = drm_find_file_by_proc(dev, curthread);
54 	DRM_UNLOCK(dev);
55 
56 	if (!file_priv) {
57 		DRM_ERROR("Could not find authenticator!\n");
58 		return EINVAL;
59 	}
60 
61 	if (!file_priv->authenticated)
62 		return EACCES;
63 
64 	DRM_DEBUG("called with offset %016jx\n", (uintmax_t)offset);
65 	if (dev->dma && offset < ptoa(dev->dma->page_count)) {
66 		drm_device_dma_t *dma = dev->dma;
67 
68 		spin_lock(&dev->dma_lock);
69 
70 		if (dma->pagelist != NULL) {
71 			unsigned long page = offset >> PAGE_SHIFT;
72 			unsigned long phys = dma->pagelist[page];
73 
74 			spin_unlock(&dev->dma_lock);
75 			// XXX *paddr = phys;
76 			ap->a_result = phys;
77 			return 0;
78 		} else {
79 			spin_unlock(&dev->dma_lock);
80 			return -1;
81 		}
82 	}
83 
84 	/* A sequential search of a linked list is
85 	   fine here because: 1) there will only be
86 	   about 5-10 entries in the list and, 2) a
87 	   DRI client only has to do this mapping
88 	   once, so it doesn't have to be optimized
89 	   for performance, even if the list was a
90 	   bit longer.
91 	*/
92 	DRM_LOCK(dev);
93 	TAILQ_FOREACH(map, &dev->maplist, link) {
94 		if (offset >> DRM_MAP_HANDLE_SHIFT ==
95 		    (unsigned long)map->handle >> DRM_MAP_HANDLE_SHIFT)
96 			break;
97 	}
98 
99 	if (map == NULL) {
100 		DRM_DEBUG("Can't find map, request offset = %016jx\n",
101 		    (uintmax_t)offset);
102 		TAILQ_FOREACH(map, &dev->maplist, link) {
103 			DRM_DEBUG("map offset = %016lx, handle = %016lx\n",
104 			    map->offset, (unsigned long)map->handle);
105 		}
106 		DRM_UNLOCK(dev);
107 		return -1;
108 	}
109 	if (((map->flags & _DRM_RESTRICTED) && !DRM_SUSER(DRM_CURPROC))) {
110 		DRM_UNLOCK(dev);
111 		DRM_DEBUG("restricted map\n");
112 		return -1;
113 	}
114 	type = map->type;
115 	DRM_UNLOCK(dev);
116 
117 	offset = offset & ((1ULL << DRM_MAP_HANDLE_SHIFT) - 1);
118 
119 	switch (type) {
120 	case _DRM_FRAME_BUFFER:
121 	case _DRM_AGP:
122 #if 0	/* XXX */
123 		*memattr = VM_MEMATTR_WRITE_COMBINING;
124 #endif
125 		/* FALLTHROUGH */
126 	case _DRM_REGISTERS:
127 		phys = map->offset + offset;
128 		break;
129 	case _DRM_SCATTER_GATHER:
130 #if 0	/* XXX */
131 		*memattr = VM_MEMATTR_WRITE_COMBINING;
132 #endif
133 		/* FALLTHROUGH */
134 	case _DRM_CONSISTENT:
135 	case _DRM_SHM:
136 		phys = vtophys((char *)map->virtual + offset);
137 		break;
138 	default:
139 		DRM_ERROR("bad map type %d\n", type);
140 		return -1;	/* This should never happen. */
141 	}
142 
143 	ap->a_result = atop(phys);
144 	return 0;
145 }
146 
147 /* XXX The following is just temporary hack to replace the
148  * vm_phys_fictitious functions available on FreeBSD
149  */
150 #define VM_PHYS_FICTITIOUS_NSEGS        8
151 static struct vm_phys_fictitious_seg {
152         vm_paddr_t      start;
153         vm_paddr_t      end;
154         vm_page_t       first_page;
155 } vm_phys_fictitious_segs[VM_PHYS_FICTITIOUS_NSEGS];
156 static struct mtx vm_phys_fictitious_reg_mtx = MTX_INITIALIZER;
157 
158 MALLOC_DEFINE(M_FICT_PAGES, "", "");
159 
160 vm_page_t
161 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
162 {
163         struct vm_phys_fictitious_seg *seg;
164         vm_page_t m;
165         int segind;
166 
167         m = NULL;
168         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
169                 seg = &vm_phys_fictitious_segs[segind];
170                 if (pa >= seg->start && pa < seg->end) {
171                         m = &seg->first_page[atop(pa - seg->start)];
172                         KASSERT((m->flags & PG_FICTITIOUS) != 0,
173                             ("%p not fictitious", m));
174                         break;
175                 }
176         }
177         return (m);
178 }
179 
180 int
181 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
182     vm_memattr_t memattr)
183 {
184         struct vm_phys_fictitious_seg *seg;
185         vm_page_t fp;
186         long i, page_count;
187         int segind;
188 
189         page_count = (end - start) / PAGE_SIZE;
190 
191         fp = kmalloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
192                     M_WAITOK | M_ZERO);
193 
194         for (i = 0; i < page_count; i++) {
195 		vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr);
196 		fp[i].flags &= ~(PG_BUSY | PG_UNMANAGED);
197         }
198         mtx_lock(&vm_phys_fictitious_reg_mtx);
199         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
200                 seg = &vm_phys_fictitious_segs[segind];
201                 if (seg->start == 0 && seg->end == 0) {
202                         seg->start = start;
203                         seg->end = end;
204                         seg->first_page = fp;
205                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
206                         return (0);
207                 }
208         }
209         mtx_unlock(&vm_phys_fictitious_reg_mtx);
210         kfree(fp, M_FICT_PAGES);
211         return (EBUSY);
212 }
213 
214 void
215 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
216 {
217 	struct vm_phys_fictitious_seg *seg;
218 	vm_page_t fp;
219 	int segind;
220 
221 	mtx_lock(&vm_phys_fictitious_reg_mtx);
222 	for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
223 		seg = &vm_phys_fictitious_segs[segind];
224 		if (seg->start == start && seg->end == end) {
225 			seg->start = seg->end = 0;
226 			fp = seg->first_page;
227 			seg->first_page = NULL;
228 			mtx_unlock(&vm_phys_fictitious_reg_mtx);
229 			kfree(fp, M_FICT_PAGES);
230 			return;
231 		}
232 	}
233 	mtx_unlock(&vm_phys_fictitious_reg_mtx);
234 	KASSERT(0, ("Unregistering not registered fictitious range"));
235 }
236