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
12#include "gt/intel_gt.h"
13#include "i915_drv.h"
14#include "i915_gem_object.h"
15#include "i915_gem_object_frontbuffer.h"
16#include "i915_gem_region.h"
17#include "i915_gem_tiling.h"
18#include "i915_scatterlist.h"
19
20static 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 drm_i915_private *i915 = to_i915(dev: obj->base.dev);
24 struct scatterlist *sg;
25 struct sg_table *st;
26 dma_addr_t dma;
27 void *vaddr;
28 void *dst;
29 int i;
30
31 /* Contiguous chunk, with a single scatterlist element */
32 if (overflows_type(obj->base.size, sg->length))
33 return -E2BIG;
34
35 if (GEM_WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
36 return -EINVAL;
37
38 /*
39 * Always aligning to the object size, allows a single allocation
40 * to handle all possible callers, and given typical object sizes,
41 * the alignment of the buddy allocation will naturally match.
42 */
43 vaddr = dma_alloc_coherent(dev: obj->base.dev->dev,
44 roundup_pow_of_two(obj->base.size),
45 dma_handle: &dma, GFP_KERNEL);
46 if (!vaddr)
47 return -ENOMEM;
48
49 st = kmalloc(sizeof(*st), GFP_KERNEL);
50 if (!st)
51 goto err_pci;
52
53 if (sg_alloc_table(st, 1, GFP_KERNEL))
54 goto err_st;
55
56 sg = st->sgl;
57 sg->offset = 0;
58 sg->length = obj->base.size;
59
60 sg_assign_page(sg, page: (struct page *)vaddr);
61 sg_dma_address(sg) = dma;
62 sg_dma_len(sg) = obj->base.size;
63
64 dst = vaddr;
65 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
66 struct page *page;
67
68 page = shmem_read_mapping_page(mapping, index: i);
69 if (IS_ERR(ptr: page))
70 goto err_st;
71
72 memcpy_from_page(to: dst, page, offset: 0, PAGE_SIZE);
73 drm_clflush_virt_range(addr: dst, PAGE_SIZE);
74
75 put_page(page);
76 dst += PAGE_SIZE;
77 }
78
79 intel_gt_chipset_flush(gt: to_gt(i915));
80
81 /* We're no longer struct page backed */
82 obj->mem_flags &= ~I915_BO_FLAG_STRUCT_PAGE;
83 __i915_gem_object_set_pages(obj, pages: st);
84
85 return 0;
86
87err_st:
88 kfree(objp: st);
89err_pci:
90 dma_free_coherent(dev: obj->base.dev->dev,
91 roundup_pow_of_two(obj->base.size),
92 cpu_addr: vaddr, dma_handle: dma);
93 return -ENOMEM;
94}
95
96void
97i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj,
98 struct sg_table *pages)
99{
100 dma_addr_t dma = sg_dma_address(pages->sgl);
101 void *vaddr = sg_page(sg: pages->sgl);
102
103 __i915_gem_object_release_shmem(obj, pages, needs_clflush: false);
104
105 if (obj->mm.dirty) {
106 struct address_space *mapping = obj->base.filp->f_mapping;
107 void *src = vaddr;
108 int i;
109
110 for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
111 struct page *page;
112
113 page = shmem_read_mapping_page(mapping, index: i);
114 if (IS_ERR(ptr: page))
115 continue;
116
117 drm_clflush_virt_range(addr: src, PAGE_SIZE);
118 memcpy_to_page(page, offset: 0, from: src, PAGE_SIZE);
119
120 set_page_dirty(page);
121 if (obj->mm.madv == I915_MADV_WILLNEED)
122 mark_page_accessed(page);
123 put_page(page);
124
125 src += PAGE_SIZE;
126 }
127 obj->mm.dirty = false;
128 }
129
130 sg_free_table(pages);
131 kfree(objp: pages);
132
133 dma_free_coherent(dev: obj->base.dev->dev,
134 roundup_pow_of_two(obj->base.size),
135 cpu_addr: vaddr, dma_handle: dma);
136}
137
138int i915_gem_object_pwrite_phys(struct drm_i915_gem_object *obj,
139 const struct drm_i915_gem_pwrite *args)
140{
141 void *vaddr = sg_page(sg: obj->mm.pages->sgl) + args->offset;
142 char __user *user_data = u64_to_user_ptr(args->data_ptr);
143 struct drm_i915_private *i915 = to_i915(dev: obj->base.dev);
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: ORIGIN_CPU);
158
159 if (copy_from_user(to: vaddr, from: user_data, n: args->size))
160 return -EFAULT;
161
162 drm_clflush_virt_range(addr: vaddr, length: args->size);
163 intel_gt_chipset_flush(gt: to_gt(i915));
164
165 i915_gem_object_flush_frontbuffer(obj, origin: ORIGIN_CPU);
166 return 0;
167}
168
169int 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(sg: 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(addr: vaddr, length: args->size);
183 if (copy_to_user(to: user_data, from: vaddr, n: args->size))
184 return -EFAULT;
185
186 return 0;
187}
188
189static 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(ptr: pages))
204 i915_gem_object_put_pages_shmem(obj, pages);
205
206 i915_gem_object_release_memory_region(obj);
207 return 0;
208
209err_xfer:
210 if (!IS_ERR_OR_NULL(ptr: pages))
211 __i915_gem_object_set_pages(obj, pages);
212 return err;
213}
214
215int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align)
216{
217 int err;
218
219 assert_object_held(obj);
220
221 if (align > obj->base.size)
222 return -EINVAL;
223
224 if (!i915_gem_object_is_shmem(obj))
225 return -EINVAL;
226
227 if (!i915_gem_object_has_struct_page(obj))
228 return 0;
229
230 err = i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE);
231 if (err)
232 return err;
233
234 if (obj->mm.madv != I915_MADV_WILLNEED)
235 return -EFAULT;
236
237 if (i915_gem_object_has_tiling_quirk(obj))
238 return -EFAULT;
239
240 if (obj->mm.mapping || i915_gem_object_has_pinned_pages(obj))
241 return -EBUSY;
242
243 if (unlikely(obj->mm.madv != I915_MADV_WILLNEED)) {
244 drm_dbg(obj->base.dev,
245 "Attempting to obtain a purgeable object\n");
246 return -EFAULT;
247 }
248
249 return i915_gem_object_shmem_to_phys(obj);
250}
251
252#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
253#include "selftests/i915_gem_phys.c"
254#endif
255