1 /*
2 * SPDX-License-Identifier: MIT
3 *
4 * Copyright © 2014-2016 Intel Corporation
5 */
6
7 #include <linux/highmem.h>
8 #include <linux/shmem_fs.h>
9 #include <linux/swap.h>
10
11 #include <drm/drm.h> /* for drm_legacy.h! */
12 #include <drm/drm_cache.h>
13
14 #include "gt/intel_gt.h"
15 #include "i915_drv.h"
16 #include "i915_gem_object.h"
17 #include "i915_gem_region.h"
18 #include "i915_scatterlist.h"
19
i915_gem_object_get_pages_phys(struct drm_i915_gem_object * obj)20 static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
21 {
22 struct address_space *mapping = obj->base.filp->f_mapping;
23 struct scatterlist *sg;
24 struct sg_table *st;
25 dma_addr_t dma;
26 void *vaddr;
27 void *dst;
28 int i;
29
30 if (GEM_WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
31 return -EINVAL;
32
33 /*
34 * Always aligning to the object size, allows a single allocation
35 * to handle all possible callers, and given typical object sizes,
36 * the alignment of the buddy allocation will naturally match.
37 */
38 vaddr = dma_alloc_coherent(obj->base.dev->dev,
39 roundup_pow_of_two(obj->base.size),
40 &dma, GFP_KERNEL);
41 if (!vaddr)
42 return -ENOMEM;
43
44 st = kmalloc(sizeof(*st), GFP_KERNEL);
45 if (!st)
46 goto err_pci;
47
48 if (sg_alloc_table(st, 1, GFP_KERNEL))
49 goto err_st;
50
51 sg = st->sgl;
52 sg->offset = 0;
53 sg->length = obj->base.size;
54
55 sg_assign_page(sg, (struct page *)vaddr);
56 sg_dma_address(sg) = dma;
57 sg_dma_len(sg) = obj->base.size;
58
59 dst = vaddr;
60 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
61 struct page *page;
62 void *src;
63
64 page = shmem_read_mapping_page(mapping, i);
65 if (IS_ERR(page))
66 goto err_st;
67
68 src = kmap_atomic(page);
69 memcpy(dst, src, PAGE_SIZE);
70 drm_clflush_virt_range(dst, PAGE_SIZE);
71 kunmap_atomic(src);
72
73 put_page(page);
74 dst += PAGE_SIZE;
75 }
76
77 intel_gt_chipset_flush(&to_i915(obj->base.dev)->gt);
78
79 /* We're no longer struct page backed */
80 obj->flags &= ~I915_BO_ALLOC_STRUCT_PAGE;
81 __i915_gem_object_set_pages(obj, st, sg->length);
82
83 return 0;
84
85 err_st:
86 kfree(st);
87 err_pci:
88 dma_free_coherent(obj->base.dev->dev,
89 roundup_pow_of_two(obj->base.size),
90 vaddr, dma);
91 return -ENOMEM;
92 }
93
94 void
i915_gem_object_put_pages_phys(struct drm_i915_gem_object * obj,struct sg_table * pages)95 i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj,
96 struct sg_table *pages)
97 {
98 dma_addr_t dma = sg_dma_address(pages->sgl);
99 void *vaddr = sg_page(pages->sgl);
100
101 __i915_gem_object_release_shmem(obj, pages, false);
102
103 if (obj->mm.dirty) {
104 struct address_space *mapping = obj->base.filp->f_mapping;
105 void *src = vaddr;
106 int i;
107
108 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
109 struct page *page;
110 char *dst;
111
112 page = shmem_read_mapping_page(mapping, i);
113 if (IS_ERR(page))
114 continue;
115
116 dst = kmap_atomic(page);
117 drm_clflush_virt_range(src, PAGE_SIZE);
118 memcpy(dst, src, PAGE_SIZE);
119 kunmap_atomic(dst);
120
121 set_page_dirty(page);
122 if (obj->mm.madv == I915_MADV_WILLNEED)
123 mark_page_accessed(page);
124 put_page(page);
125
126 src += PAGE_SIZE;
127 }
128 obj->mm.dirty = false;
129 }
130
131 sg_free_table(pages);
132 kfree(pages);
133
134 dma_free_coherent(obj->base.dev->dev,
135 roundup_pow_of_two(obj->base.size),
136 vaddr, dma);
137 }
138
i915_gem_object_pwrite_phys(struct drm_i915_gem_object * obj,const struct drm_i915_gem_pwrite * args)139 int i915_gem_object_pwrite_phys(struct drm_i915_gem_object *obj,
140 const struct drm_i915_gem_pwrite *args)
141 {
142 void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset;
143 char __user *user_data = u64_to_user_ptr(args->data_ptr);
144 int err;
145
146 err = i915_gem_object_wait(obj,
147 I915_WAIT_INTERRUPTIBLE |
148 I915_WAIT_ALL,
149 MAX_SCHEDULE_TIMEOUT);
150 if (err)
151 return err;
152
153 /*
154 * We manually control the domain here and pretend that it
155 * remains coherent i.e. in the GTT domain, like shmem_pwrite.
156 */
157 i915_gem_object_invalidate_frontbuffer(obj, ORIGIN_CPU);
158
159 if (copy_from_user(vaddr, user_data, args->size))
160 return -EFAULT;
161
162 drm_clflush_virt_range(vaddr, args->size);
163 intel_gt_chipset_flush(&to_i915(obj->base.dev)->gt);
164
165 i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU);
166 return 0;
167 }
168
i915_gem_object_pread_phys(struct drm_i915_gem_object * obj,const struct drm_i915_gem_pread * args)169 int i915_gem_object_pread_phys(struct drm_i915_gem_object *obj,
170 const struct drm_i915_gem_pread *args)
171 {
172 void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset;
173 char __user *user_data = u64_to_user_ptr(args->data_ptr);
174 int err;
175
176 err = i915_gem_object_wait(obj,
177 I915_WAIT_INTERRUPTIBLE,
178 MAX_SCHEDULE_TIMEOUT);
179 if (err)
180 return err;
181
182 drm_clflush_virt_range(vaddr, args->size);
183 if (copy_to_user(user_data, vaddr, args->size))
184 return -EFAULT;
185
186 return 0;
187 }
188
i915_gem_object_shmem_to_phys(struct drm_i915_gem_object * obj)189 static int i915_gem_object_shmem_to_phys(struct drm_i915_gem_object *obj)
190 {
191 struct sg_table *pages;
192 int err;
193
194 pages = __i915_gem_object_unset_pages(obj);
195
196 err = i915_gem_object_get_pages_phys(obj);
197 if (err)
198 goto err_xfer;
199
200 /* Perma-pin (until release) the physical set of pages */
201 __i915_gem_object_pin_pages(obj);
202
203 if (!IS_ERR_OR_NULL(pages))
204 i915_gem_object_put_pages_shmem(obj, pages);
205
206 i915_gem_object_release_memory_region(obj);
207 return 0;
208
209 err_xfer:
210 if (!IS_ERR_OR_NULL(pages)) {
211 unsigned int sg_page_sizes = i915_sg_page_sizes(pages->sgl);
212
213 __i915_gem_object_set_pages(obj, pages, sg_page_sizes);
214 }
215 return err;
216 }
217
i915_gem_object_attach_phys(struct drm_i915_gem_object * obj,int align)218 int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align)
219 {
220 int err;
221
222 assert_object_held(obj);
223
224 if (align > obj->base.size)
225 return -EINVAL;
226
227 if (!i915_gem_object_is_shmem(obj))
228 return -EINVAL;
229
230 if (!i915_gem_object_has_struct_page(obj))
231 return 0;
232
233 err = i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE);
234 if (err)
235 return err;
236
237 if (obj->mm.madv != I915_MADV_WILLNEED)
238 return -EFAULT;
239
240 if (i915_gem_object_has_tiling_quirk(obj))
241 return -EFAULT;
242
243 if (obj->mm.mapping || i915_gem_object_has_pinned_pages(obj))
244 return -EBUSY;
245
246 if (unlikely(obj->mm.madv != I915_MADV_WILLNEED)) {
247 drm_dbg(obj->base.dev,
248 "Attempting to obtain a purgeable object\n");
249 return -EFAULT;
250 }
251
252 return i915_gem_object_shmem_to_phys(obj);
253 }
254
255 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
256 #include "selftests/i915_gem_phys.c"
257 #endif
258