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1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2020 Intel Corporation
4 */
5
6#include <linux/iosys-map.h>
7#include <linux/mm.h>
8#include <linux/pagemap.h>
9#include <linux/shmem_fs.h>
10
11#include "gem/i915_gem_object.h"
12#include "gem/i915_gem_lmem.h"
13#include "shmem_utils.h"
14
15struct file *shmem_create_from_data(const char *name, void *data, size_t len)
16{
17 struct file *file;
18 int err;
19
20 file = shmem_file_setup(name, PAGE_ALIGN(len), VM_NORESERVE);
21 if (IS_ERR(file))
22 return file;
23
24 err = shmem_write(file, 0, data, len);
25 if (err) {
26 fput(file);
27 return ERR_PTR(err);
28 }
29
30 return file;
31}
32
33struct file *shmem_create_from_object(struct drm_i915_gem_object *obj)
34{
35 struct file *file;
36 void *ptr;
37
38 if (i915_gem_object_is_shmem(obj)) {
39 file = obj->base.filp;
40 atomic_long_inc(&file->f_count);
41 return file;
42 }
43
44 ptr = i915_gem_object_pin_map_unlocked(obj, i915_gem_object_is_lmem(obj) ?
45 I915_MAP_WC : I915_MAP_WB);
46 if (IS_ERR(ptr))
47 return ERR_CAST(ptr);
48
49 file = shmem_create_from_data("", ptr, obj->base.size);
50 i915_gem_object_unpin_map(obj);
51
52 return file;
53}
54
55void *shmem_pin_map(struct file *file)
56{
57 struct page **pages;
58 size_t n_pages, i;
59 void *vaddr;
60
61 n_pages = file->f_mapping->host->i_size >> PAGE_SHIFT;
62 pages = kvmalloc_array(n_pages, sizeof(*pages), GFP_KERNEL);
63 if (!pages)
64 return NULL;
65
66 for (i = 0; i < n_pages; i++) {
67 pages[i] = shmem_read_mapping_page_gfp(file->f_mapping, i,
68 GFP_KERNEL);
69 if (IS_ERR(pages[i]))
70 goto err_page;
71 }
72
73 vaddr = vmap(pages, n_pages, VM_MAP_PUT_PAGES, PAGE_KERNEL);
74 if (!vaddr)
75 goto err_page;
76 mapping_set_unevictable(file->f_mapping);
77 return vaddr;
78err_page:
79 while (i--)
80 put_page(pages[i]);
81 kvfree(pages);
82 return NULL;
83}
84
85void shmem_unpin_map(struct file *file, void *ptr)
86{
87 mapping_clear_unevictable(file->f_mapping);
88 vfree(ptr);
89}
90
91static int __shmem_rw(struct file *file, loff_t off,
92 void *ptr, size_t len,
93 bool write)
94{
95 unsigned long pfn;
96
97 for (pfn = off >> PAGE_SHIFT; len; pfn++) {
98 unsigned int this =
99 min_t(size_t, PAGE_SIZE - offset_in_page(off), len);
100 struct page *page;
101 void *vaddr;
102
103 page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
104 GFP_KERNEL);
105 if (IS_ERR(page))
106 return PTR_ERR(page);
107
108 vaddr = kmap(page);
109 if (write) {
110 memcpy(vaddr + offset_in_page(off), ptr, this);
111 set_page_dirty(page);
112 } else {
113 memcpy(ptr, vaddr + offset_in_page(off), this);
114 }
115 mark_page_accessed(page);
116 kunmap(page);
117 put_page(page);
118
119 len -= this;
120 ptr += this;
121 off = 0;
122 }
123
124 return 0;
125}
126
127int shmem_read_to_iosys_map(struct file *file, loff_t off,
128 struct iosys_map *map, size_t map_off, size_t len)
129{
130 unsigned long pfn;
131
132 for (pfn = off >> PAGE_SHIFT; len; pfn++) {
133 unsigned int this =
134 min_t(size_t, PAGE_SIZE - offset_in_page(off), len);
135 struct page *page;
136 void *vaddr;
137
138 page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
139 GFP_KERNEL);
140 if (IS_ERR(page))
141 return PTR_ERR(page);
142
143 vaddr = kmap(page);
144 iosys_map_memcpy_to(map, map_off, vaddr + offset_in_page(off),
145 this);
146 mark_page_accessed(page);
147 kunmap(page);
148 put_page(page);
149
150 len -= this;
151 map_off += this;
152 off = 0;
153 }
154
155 return 0;
156}
157
158int shmem_read(struct file *file, loff_t off, void *dst, size_t len)
159{
160 return __shmem_rw(file, off, dst, len, false);
161}
162
163int shmem_write(struct file *file, loff_t off, void *src, size_t len)
164{
165 return __shmem_rw(file, off, src, len, true);
166}
167
168#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
169#include "st_shmem_utils.c"
170#endif
1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2020 Intel Corporation
4 */
5
6#include <linux/mm.h>
7#include <linux/pagemap.h>
8#include <linux/shmem_fs.h>
9
10#include "gem/i915_gem_object.h"
11#include "shmem_utils.h"
12
13struct file *shmem_create_from_data(const char *name, void *data, size_t len)
14{
15 struct file *file;
16 int err;
17
18 file = shmem_file_setup(name, PAGE_ALIGN(len), VM_NORESERVE);
19 if (IS_ERR(file))
20 return file;
21
22 err = shmem_write(file, 0, data, len);
23 if (err) {
24 fput(file);
25 return ERR_PTR(err);
26 }
27
28 return file;
29}
30
31struct file *shmem_create_from_object(struct drm_i915_gem_object *obj)
32{
33 struct file *file;
34 void *ptr;
35
36 if (obj->ops == &i915_gem_shmem_ops) {
37 file = obj->base.filp;
38 atomic_long_inc(&file->f_count);
39 return file;
40 }
41
42 ptr = i915_gem_object_pin_map(obj, I915_MAP_WB);
43 if (IS_ERR(ptr))
44 return ERR_CAST(ptr);
45
46 file = shmem_create_from_data("", ptr, obj->base.size);
47 i915_gem_object_unpin_map(obj);
48
49 return file;
50}
51
52static size_t shmem_npte(struct file *file)
53{
54 return file->f_mapping->host->i_size >> PAGE_SHIFT;
55}
56
57static void __shmem_unpin_map(struct file *file, void *ptr, size_t n_pte)
58{
59 unsigned long pfn;
60
61 vunmap(ptr);
62
63 for (pfn = 0; pfn < n_pte; pfn++) {
64 struct page *page;
65
66 page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
67 GFP_KERNEL);
68 if (!WARN_ON(IS_ERR(page))) {
69 put_page(page);
70 put_page(page);
71 }
72 }
73}
74
75void *shmem_pin_map(struct file *file)
76{
77 const size_t n_pte = shmem_npte(file);
78 pte_t *stack[32], **ptes, **mem;
79 struct vm_struct *area;
80 unsigned long pfn;
81
82 mem = stack;
83 if (n_pte > ARRAY_SIZE(stack)) {
84 mem = kvmalloc_array(n_pte, sizeof(*mem), GFP_KERNEL);
85 if (!mem)
86 return NULL;
87 }
88
89 area = alloc_vm_area(n_pte << PAGE_SHIFT, mem);
90 if (!area) {
91 if (mem != stack)
92 kvfree(mem);
93 return NULL;
94 }
95
96 ptes = mem;
97 for (pfn = 0; pfn < n_pte; pfn++) {
98 struct page *page;
99
100 page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
101 GFP_KERNEL);
102 if (IS_ERR(page))
103 goto err_page;
104
105 **ptes++ = mk_pte(page, PAGE_KERNEL);
106 }
107
108 if (mem != stack)
109 kvfree(mem);
110
111 mapping_set_unevictable(file->f_mapping);
112 return area->addr;
113
114err_page:
115 if (mem != stack)
116 kvfree(mem);
117
118 __shmem_unpin_map(file, area->addr, pfn);
119 return NULL;
120}
121
122void shmem_unpin_map(struct file *file, void *ptr)
123{
124 mapping_clear_unevictable(file->f_mapping);
125 __shmem_unpin_map(file, ptr, shmem_npte(file));
126}
127
128static int __shmem_rw(struct file *file, loff_t off,
129 void *ptr, size_t len,
130 bool write)
131{
132 unsigned long pfn;
133
134 for (pfn = off >> PAGE_SHIFT; len; pfn++) {
135 unsigned int this =
136 min_t(size_t, PAGE_SIZE - offset_in_page(off), len);
137 struct page *page;
138 void *vaddr;
139
140 page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
141 GFP_KERNEL);
142 if (IS_ERR(page))
143 return PTR_ERR(page);
144
145 vaddr = kmap(page);
146 if (write)
147 memcpy(vaddr + offset_in_page(off), ptr, this);
148 else
149 memcpy(ptr, vaddr + offset_in_page(off), this);
150 kunmap(page);
151 put_page(page);
152
153 len -= this;
154 ptr += this;
155 off = 0;
156 }
157
158 return 0;
159}
160
161int shmem_read(struct file *file, loff_t off, void *dst, size_t len)
162{
163 return __shmem_rw(file, off, dst, len, false);
164}
165
166int shmem_write(struct file *file, loff_t off, void *src, size_t len)
167{
168 return __shmem_rw(file, off, src, len, true);
169}
170
171#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
172#include "st_shmem_utils.c"
173#endif