xref: /netbsd-src/sys/external/bsd/drm2/drm/drm_gem_cma_helper.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* $NetBSD: drm_gem_cma_helper.c,v 1.1 2017/12/26 14:53:12 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2015-2017 Jared McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: drm_gem_cma_helper.c,v 1.1 2017/12/26 14:53:12 jmcneill Exp $");
31 
32 #include <drm/drmP.h>
33 #include <drm/drm_gem_cma_helper.h>
34 
35 #include <uvm/uvm.h>
36 
37 struct drm_gem_cma_object *
38 drm_gem_cma_create(struct drm_device *ddev, unsigned int size)
39 {
40 	struct drm_gem_cma_object *obj;
41 	int error, nsegs;
42 
43 	obj = kmem_zalloc(sizeof(*obj), KM_SLEEP);
44 	obj->dmat = ddev->bus_dmat;
45 	obj->dmasize = size;
46 
47         error = bus_dmamem_alloc(obj->dmat, obj->dmasize, PAGE_SIZE, 0,
48 	    obj->dmasegs, 1, &nsegs, BUS_DMA_WAITOK);
49 	if (error)
50 		goto failed;
51 	error = bus_dmamem_map(obj->dmat, obj->dmasegs, nsegs,
52 	    obj->dmasize, &obj->vaddr, BUS_DMA_WAITOK | BUS_DMA_COHERENT);
53 	if (error)
54 		goto free;
55 	error = bus_dmamap_create(obj->dmat, obj->dmasize, 1,
56 	    obj->dmasize, 0, BUS_DMA_WAITOK, &obj->dmamap);
57 	if (error)
58 		goto unmap;
59 	error = bus_dmamap_load(obj->dmat, obj->dmamap, obj->vaddr,
60 	    obj->dmasize, NULL, BUS_DMA_WAITOK);
61 	if (error)
62 		goto destroy;
63 
64 	memset(obj->vaddr, 0, obj->dmasize);
65 
66 	drm_gem_private_object_init(ddev, &obj->base, size);
67 
68 	return obj;
69 
70 destroy:
71 	bus_dmamap_destroy(obj->dmat, obj->dmamap);
72 unmap:
73 	bus_dmamem_unmap(obj->dmat, obj->vaddr, obj->dmasize);
74 free:
75 	bus_dmamem_free(obj->dmat, obj->dmasegs, nsegs);
76 failed:
77 	kmem_free(obj, sizeof(*obj));
78 
79 	return NULL;
80 }
81 
82 static void
83 drm_gem_cma_obj_free(struct drm_gem_cma_object *obj)
84 {
85 	bus_dmamap_unload(obj->dmat, obj->dmamap);
86 	bus_dmamap_destroy(obj->dmat, obj->dmamap);
87 	bus_dmamem_unmap(obj->dmat, obj->vaddr, obj->dmasize);
88 	bus_dmamem_free(obj->dmat, obj->dmasegs, 1);
89 	kmem_free(obj, sizeof(*obj));
90 }
91 
92 void
93 drm_gem_cma_free_object(struct drm_gem_object *gem_obj)
94 {
95 	struct drm_gem_cma_object *obj = to_drm_gem_cma_obj(gem_obj);
96 
97 	drm_gem_free_mmap_offset(gem_obj);
98 	drm_gem_object_release(gem_obj);
99 	drm_gem_cma_obj_free(obj);
100 }
101 
102 int
103 drm_gem_cma_dumb_create(struct drm_file *file_priv, struct drm_device *ddev,
104     struct drm_mode_create_dumb *args)
105 {
106 	struct drm_gem_cma_object *obj;
107 	uint32_t handle;
108 	int error;
109 
110 	args->pitch = args->width * ((args->bpp + 7) / 8);
111 	args->size = args->pitch * args->height;
112 	args->size = roundup(args->size, PAGE_SIZE);
113 	args->handle = 0;
114 
115 	obj = drm_gem_cma_create(ddev, args->size);
116 	if (obj == NULL)
117 		return -ENOMEM;
118 
119 	error = drm_gem_handle_create(file_priv, &obj->base, &handle);
120 	drm_gem_object_unreference_unlocked(&obj->base);
121 	if (error) {
122 		drm_gem_cma_obj_free(obj);
123 		return error;
124 	}
125 
126 	args->handle = handle;
127 
128 	return 0;
129 }
130 
131 int
132 drm_gem_cma_dumb_map_offset(struct drm_file *file_priv, struct drm_device *ddev,
133     uint32_t handle, uint64_t *offset)
134 {
135 	struct drm_gem_object *gem_obj;
136 	struct drm_gem_cma_object *obj;
137 	int error;
138 
139 	gem_obj = drm_gem_object_lookup(ddev, file_priv, handle);
140 	if (gem_obj == NULL)
141 		return -ENOENT;
142 
143 	obj = to_drm_gem_cma_obj(gem_obj);
144 
145 	if (drm_vma_node_has_offset(&obj->base.vma_node) == 0) {
146 		error = drm_gem_create_mmap_offset(&obj->base);
147 		if (error)
148 			goto done;
149 	} else {
150 		error = 0;
151 	}
152 
153 	*offset = drm_vma_node_offset_addr(&obj->base.vma_node);
154 
155 done:
156 	drm_gem_object_unreference_unlocked(&obj->base);
157 
158 	return error;
159 }
160 
161 static int
162 drm_gem_cma_fault(struct uvm_faultinfo *ufi, vaddr_t vaddr,
163     struct vm_page **pps, int npages, int centeridx, vm_prot_t access_type,
164     int flags)
165 {
166 	struct vm_map_entry *entry = ufi->entry;
167 	struct uvm_object *uobj = entry->object.uvm_obj;
168 	struct drm_gem_object *gem_obj =
169 	    container_of(uobj, struct drm_gem_object, gemo_uvmobj);
170 	struct drm_gem_cma_object *obj = to_drm_gem_cma_obj(gem_obj);
171 	off_t curr_offset;
172 	vaddr_t curr_va;
173 	paddr_t paddr, mdpgno;
174 	u_int mmapflags;
175 	int lcv, retval;
176 	vm_prot_t mapprot;
177 
178 	if (UVM_ET_ISCOPYONWRITE(entry))
179 		return -EIO;
180 
181 	curr_offset = entry->offset + (vaddr - entry->start);
182 	curr_va = vaddr;
183 
184 	retval = 0;
185 	for (lcv = 0; lcv < npages; lcv++, curr_offset += PAGE_SIZE,
186 	    curr_va += PAGE_SIZE) {
187 		if ((flags & PGO_ALLPAGES) == 0 && lcv != centeridx)
188 			continue;
189 		if (pps[lcv] == PGO_DONTCARE)
190 			continue;
191 
192 		mdpgno = bus_dmamem_mmap(obj->dmat, obj->dmasegs, 1,
193 		    curr_offset, access_type, BUS_DMA_PREFETCHABLE);
194 		if (mdpgno == -1) {
195 			retval = -EIO;
196 			break;
197 		}
198 		paddr = pmap_phys_address(mdpgno);
199 		mmapflags = pmap_mmap_flags(mdpgno);
200 		mapprot = ufi->entry->protection;
201 
202 		if (pmap_enter(ufi->orig_map->pmap, curr_va, paddr, mapprot,
203 		    PMAP_CANFAIL | mapprot | mmapflags) != 0) {
204 			pmap_update(ufi->orig_map->pmap);
205 			uvmfault_unlockall(ufi, ufi->entry->aref.ar_amap, uobj);
206 			uvm_wait("drm_gem_cma_fault");
207 			return -ERESTART;
208 		}
209 	}
210 
211 	pmap_update(ufi->orig_map->pmap);
212 	uvmfault_unlockall(ufi, ufi->entry->aref.ar_amap, uobj);
213 
214 	return retval;
215 }
216 
217 const struct uvm_pagerops drm_gem_cma_uvm_ops = {
218 	.pgo_reference = drm_gem_pager_reference,
219 	.pgo_detach = drm_gem_pager_detach,
220 	.pgo_fault = drm_gem_cma_fault,
221 };
222