1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2014-2016 Intel Corporation
4 */
5
6#include <linux/highmem.h>
7#include <linux/shmem_fs.h>
8#include <linux/swap.h>
9
10#include <drm/drm_cache.h>
11#include <drm/drm_print.h>
12
13#include "gt/intel_gt.h"
14#include "i915_drv.h"
15#include "i915_gem_object.h"
16#include "i915_gem_object_frontbuffer.h"
17#include "i915_gem_region.h"
18#include "i915_gem_tiling.h"
19#include "i915_scatterlist.h"
20
21static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
22{
23 struct address_space *mapping = obj->base.filp->f_mapping;
24 struct drm_i915_private *i915 = to_i915(dev: obj->base.dev);
25 struct scatterlist *sg;
26 struct sg_table *st;
27 dma_addr_t dma;
28 void *vaddr;
29 void *dst;
30 int i;
31
32 /* Contiguous chunk, with a single scatterlist element */
33 if (overflows_type(obj->base.size, sg->length))
34 return -E2BIG;
35
36 if (GEM_WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
37 return -EINVAL;
38
39 /*
40 * Always aligning to the object size, allows a single allocation
41 * to handle all possible callers, and given typical object sizes,
42 * the alignment of the buddy allocation will naturally match.
43 */
44 vaddr = dma_alloc_coherent(dev: obj->base.dev->dev,
45 roundup_pow_of_two(obj->base.size),
46 dma_handle: &dma, GFP_KERNEL);
47 if (!vaddr)
48 return -ENOMEM;
49
50 st = kmalloc(sizeof(*st), GFP_KERNEL);
51 if (!st)
52 goto err_pci;
53
54 if (sg_alloc_table(st, 1, GFP_KERNEL))
55 goto err_st;
56
57 sg = st->sgl;
58 sg->offset = 0;
59 sg->length = obj->base.size;
60
61 sg_assign_page(sg, page: (struct page *)vaddr);
62 sg_dma_address(sg) = dma;
63 sg_dma_len(sg) = obj->base.size;
64
65 dst = vaddr;
66 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
67 struct page *page;
68
69 page = shmem_read_mapping_page(mapping, index: i);
70 if (IS_ERR(ptr: page))
71 goto err_st;
72
73 memcpy_from_page(to: dst, page, offset: 0, PAGE_SIZE);
74 drm_clflush_virt_range(addr: dst, PAGE_SIZE);
75
76 put_page(page);
77 dst += PAGE_SIZE;
78 }
79
80 intel_gt_chipset_flush(gt: to_gt(i915));
81
82 /* We're no longer struct page backed */
83 obj->mem_flags &= ~I915_BO_FLAG_STRUCT_PAGE;
84 __i915_gem_object_set_pages(obj, pages: st);
85
86 return 0;
87
88err_st:
89 kfree(objp: st);
90err_pci:
91 dma_free_coherent(dev: obj->base.dev->dev,
92 roundup_pow_of_two(obj->base.size),
93 cpu_addr: vaddr, dma_handle: dma);
94 return -ENOMEM;
95}
96
97void
98i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj,
99 struct sg_table *pages)
100{
101 dma_addr_t dma = sg_dma_address(pages->sgl);
102 void *vaddr = sg_page(sg: pages->sgl);
103
104 __i915_gem_object_release_shmem(obj, pages, needs_clflush: false);
105
106 if (obj->mm.dirty) {
107 struct address_space *mapping = obj->base.filp->f_mapping;
108 void *src = vaddr;
109 int i;
110
111 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
112 struct page *page;
113
114 page = shmem_read_mapping_page(mapping, index: i);
115 if (IS_ERR(ptr: page))
116 continue;
117
118 drm_clflush_virt_range(addr: src, PAGE_SIZE);
119 memcpy_to_page(page, offset: 0, from: src, PAGE_SIZE);
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(objp: pages);
133
134 dma_free_coherent(dev: obj->base.dev->dev,
135 roundup_pow_of_two(obj->base.size),
136 cpu_addr: vaddr, dma_handle: dma);
137}
138
139int 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(sg: obj->mm.pages->sgl) + args->offset;
143 char __user *user_data = u64_to_user_ptr(args->data_ptr);
144 struct drm_i915_private *i915 = to_i915(dev: obj->base.dev);
145 int err;
146
147 err = i915_gem_object_wait(obj,
148 I915_WAIT_INTERRUPTIBLE |
149 I915_WAIT_ALL,
150 MAX_SCHEDULE_TIMEOUT);
151 if (err)
152 return err;
153
154 /*
155 * We manually control the domain here and pretend that it
156 * remains coherent i.e. in the GTT domain, like shmem_pwrite.
157 */
158 i915_gem_object_invalidate_frontbuffer(obj, origin: ORIGIN_CPU);
159
160 if (copy_from_user(to: vaddr, from: user_data, n: args->size))
161 return -EFAULT;
162
163 drm_clflush_virt_range(addr: vaddr, length: args->size);
164 intel_gt_chipset_flush(gt: to_gt(i915));
165
166 i915_gem_object_flush_frontbuffer(obj, origin: ORIGIN_CPU);
167 return 0;
168}
169
170int i915_gem_object_pread_phys(struct drm_i915_gem_object *obj,
171 const struct drm_i915_gem_pread *args)
172{
173 void *vaddr = sg_page(sg: obj->mm.pages->sgl) + args->offset;
174 char __user *user_data = u64_to_user_ptr(args->data_ptr);
175 int err;
176
177 err = i915_gem_object_wait(obj,
178 I915_WAIT_INTERRUPTIBLE,
179 MAX_SCHEDULE_TIMEOUT);
180 if (err)
181 return err;
182
183 drm_clflush_virt_range(addr: vaddr, length: args->size);
184 if (copy_to_user(to: user_data, from: vaddr, n: args->size))
185 return -EFAULT;
186
187 return 0;
188}
189
190static int i915_gem_object_shmem_to_phys(struct drm_i915_gem_object *obj)
191{
192 struct sg_table *pages;
193 int err;
194
195 pages = __i915_gem_object_unset_pages(obj);
196
197 err = i915_gem_object_get_pages_phys(obj);
198 if (err)
199 goto err_xfer;
200
201 /* Perma-pin (until release) the physical set of pages */
202 __i915_gem_object_pin_pages(obj);
203
204 if (!IS_ERR_OR_NULL(ptr: pages))
205 i915_gem_object_put_pages_shmem(obj, pages);
206
207 i915_gem_object_release_memory_region(obj);
208 return 0;
209
210err_xfer:
211 if (!IS_ERR_OR_NULL(ptr: pages))
212 __i915_gem_object_set_pages(obj, pages);
213 return err;
214}
215
216int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align)
217{
218 int err;
219
220 assert_object_held(obj);
221
222 if (align > obj->base.size)
223 return -EINVAL;
224
225 if (!i915_gem_object_is_shmem(obj))
226 return -EINVAL;
227
228 if (!i915_gem_object_has_struct_page(obj))
229 return 0;
230
231 err = i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE);
232 if (err)
233 return err;
234
235 if (obj->mm.madv != I915_MADV_WILLNEED)
236 return -EFAULT;
237
238 if (i915_gem_object_has_tiling_quirk(obj))
239 return -EFAULT;
240
241 if (obj->mm.mapping || i915_gem_object_has_pinned_pages(obj))
242 return -EBUSY;
243
244 if (unlikely(obj->mm.madv != I915_MADV_WILLNEED)) {
245 drm_dbg(obj->base.dev,
246 "Attempting to obtain a purgeable object\n");
247 return -EFAULT;
248 }
249
250 return i915_gem_object_shmem_to_phys(obj);
251}
252
253#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
254#include "selftests/i915_gem_phys.c"
255#endif
256

source code of linux/drivers/gpu/drm/i915/gem/i915_gem_phys.c