1 // SPDX-License-Identifier: GPL-2.0 <<
2 #include <linux/ceph/ceph_debug.h> 1 #include <linux/ceph/ceph_debug.h>
3 2
4 #include <linux/module.h> 3 #include <linux/module.h>
5 #include <linux/sched.h> 4 #include <linux/sched.h>
6 #include <linux/slab.h> 5 #include <linux/slab.h>
7 #include <linux/file.h> 6 #include <linux/file.h>
8 #include <linux/namei.h> 7 #include <linux/namei.h>
9 #include <linux/writeback.h> 8 #include <linux/writeback.h>
10 9
11 #include <linux/ceph/libceph.h> 10 #include <linux/ceph/libceph.h>
12 11
>> 12 /*
>> 13 * build a vector of user pages
>> 14 */
>> 15 struct page **ceph_get_direct_page_vector(const void __user *data,
>> 16 int num_pages, bool write_page)
>> 17 {
>> 18 struct page **pages;
>> 19 int got = 0;
>> 20 int rc = 0;
>> 21
>> 22 pages = kmalloc(sizeof(*pages) * num_pages, GFP_NOFS);
>> 23 if (!pages)
>> 24 return ERR_PTR(-ENOMEM);
>> 25
>> 26 while (got < num_pages) {
>> 27 rc = get_user_pages_unlocked(
>> 28 (unsigned long)data + ((unsigned long)got * PAGE_SIZE),
>> 29 num_pages - got, pages + got, write_page ? FOLL_WRITE : 0);
>> 30 if (rc < 0)
>> 31 break;
>> 32 BUG_ON(rc == 0);
>> 33 got += rc;
>> 34 }
>> 35 if (rc < 0)
>> 36 goto fail;
>> 37 return pages;
>> 38
>> 39 fail:
>> 40 ceph_put_page_vector(pages, got, false);
>> 41 return ERR_PTR(rc);
>> 42 }
>> 43 EXPORT_SYMBOL(ceph_get_direct_page_vector);
>> 44
13 void ceph_put_page_vector(struct page **pages, 45 void ceph_put_page_vector(struct page **pages, int num_pages, bool dirty)
14 { 46 {
15 int i; 47 int i;
16 48
17 for (i = 0; i < num_pages; i++) { 49 for (i = 0; i < num_pages; i++) {
18 if (dirty) 50 if (dirty)
19 set_page_dirty_lock(pa 51 set_page_dirty_lock(pages[i]);
20 put_page(pages[i]); 52 put_page(pages[i]);
21 } 53 }
22 kvfree(pages); 54 kvfree(pages);
23 } 55 }
24 EXPORT_SYMBOL(ceph_put_page_vector); 56 EXPORT_SYMBOL(ceph_put_page_vector);
25 57
26 void ceph_release_page_vector(struct page **pa 58 void ceph_release_page_vector(struct page **pages, int num_pages)
27 { 59 {
28 int i; 60 int i;
29 61
30 for (i = 0; i < num_pages; i++) 62 for (i = 0; i < num_pages; i++)
31 __free_pages(pages[i], 0); 63 __free_pages(pages[i], 0);
32 kfree(pages); 64 kfree(pages);
33 } 65 }
34 EXPORT_SYMBOL(ceph_release_page_vector); 66 EXPORT_SYMBOL(ceph_release_page_vector);
35 67
36 /* 68 /*
37 * allocate a vector new pages 69 * allocate a vector new pages
38 */ 70 */
39 struct page **ceph_alloc_page_vector(int num_p 71 struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags)
40 { 72 {
41 struct page **pages; 73 struct page **pages;
42 int i; 74 int i;
43 75
44 pages = kmalloc_array(num_pages, sizeo !! 76 pages = kmalloc(sizeof(*pages) * num_pages, flags);
45 if (!pages) 77 if (!pages)
46 return ERR_PTR(-ENOMEM); 78 return ERR_PTR(-ENOMEM);
47 for (i = 0; i < num_pages; i++) { 79 for (i = 0; i < num_pages; i++) {
48 pages[i] = __page_cache_alloc( 80 pages[i] = __page_cache_alloc(flags);
49 if (pages[i] == NULL) { 81 if (pages[i] == NULL) {
50 ceph_release_page_vect 82 ceph_release_page_vector(pages, i);
51 return ERR_PTR(-ENOMEM 83 return ERR_PTR(-ENOMEM);
52 } 84 }
53 } 85 }
54 return pages; 86 return pages;
55 } 87 }
56 EXPORT_SYMBOL(ceph_alloc_page_vector); 88 EXPORT_SYMBOL(ceph_alloc_page_vector);
57 89
58 /* 90 /*
59 * copy user data into a page vector 91 * copy user data into a page vector
60 */ 92 */
61 int ceph_copy_user_to_page_vector(struct page 93 int ceph_copy_user_to_page_vector(struct page **pages,
62 const 94 const void __user *data,
63 loff_ 95 loff_t off, size_t len)
64 { 96 {
65 int i = 0; 97 int i = 0;
66 int po = off & ~PAGE_MASK; 98 int po = off & ~PAGE_MASK;
67 int left = len; 99 int left = len;
68 int l, bad; 100 int l, bad;
69 101
70 while (left > 0) { 102 while (left > 0) {
71 l = min_t(int, PAGE_SIZE-po, l 103 l = min_t(int, PAGE_SIZE-po, left);
72 bad = copy_from_user(page_addr 104 bad = copy_from_user(page_address(pages[i]) + po, data, l);
73 if (bad == l) 105 if (bad == l)
74 return -EFAULT; 106 return -EFAULT;
75 data += l - bad; 107 data += l - bad;
76 left -= l - bad; 108 left -= l - bad;
77 po += l - bad; 109 po += l - bad;
78 if (po == PAGE_SIZE) { 110 if (po == PAGE_SIZE) {
79 po = 0; 111 po = 0;
80 i++; 112 i++;
81 } 113 }
82 } 114 }
83 return len; 115 return len;
84 } 116 }
85 EXPORT_SYMBOL(ceph_copy_user_to_page_vector); 117 EXPORT_SYMBOL(ceph_copy_user_to_page_vector);
86 118
87 void ceph_copy_to_page_vector(struct page **pa 119 void ceph_copy_to_page_vector(struct page **pages,
88 const void 120 const void *data,
89 loff_t off 121 loff_t off, size_t len)
90 { 122 {
91 int i = 0; 123 int i = 0;
92 size_t po = off & ~PAGE_MASK; 124 size_t po = off & ~PAGE_MASK;
93 size_t left = len; 125 size_t left = len;
94 126
95 while (left > 0) { 127 while (left > 0) {
96 size_t l = min_t(size_t, PAGE_ 128 size_t l = min_t(size_t, PAGE_SIZE-po, left);
97 129
98 memcpy(page_address(pages[i]) 130 memcpy(page_address(pages[i]) + po, data, l);
99 data += l; 131 data += l;
100 left -= l; 132 left -= l;
101 po += l; 133 po += l;
102 if (po == PAGE_SIZE) { 134 if (po == PAGE_SIZE) {
103 po = 0; 135 po = 0;
104 i++; 136 i++;
105 } 137 }
106 } 138 }
107 } 139 }
108 EXPORT_SYMBOL(ceph_copy_to_page_vector); 140 EXPORT_SYMBOL(ceph_copy_to_page_vector);
109 141
110 void ceph_copy_from_page_vector(struct page ** 142 void ceph_copy_from_page_vector(struct page **pages,
111 void *data 143 void *data,
112 loff_t off 144 loff_t off, size_t len)
113 { 145 {
114 int i = 0; 146 int i = 0;
115 size_t po = off & ~PAGE_MASK; 147 size_t po = off & ~PAGE_MASK;
116 size_t left = len; 148 size_t left = len;
117 149
118 while (left > 0) { 150 while (left > 0) {
119 size_t l = min_t(size_t, PAGE_ 151 size_t l = min_t(size_t, PAGE_SIZE-po, left);
120 152
121 memcpy(data, page_address(page 153 memcpy(data, page_address(pages[i]) + po, l);
122 data += l; 154 data += l;
123 left -= l; 155 left -= l;
124 po += l; 156 po += l;
125 if (po == PAGE_SIZE) { 157 if (po == PAGE_SIZE) {
126 po = 0; 158 po = 0;
127 i++; 159 i++;
128 } 160 }
129 } 161 }
130 } 162 }
131 EXPORT_SYMBOL(ceph_copy_from_page_vector); 163 EXPORT_SYMBOL(ceph_copy_from_page_vector);
132 164
133 /* 165 /*
134 * Zero an extent within a page vector. Offse 166 * Zero an extent within a page vector. Offset is relative to the
135 * start of the first page. 167 * start of the first page.
136 */ 168 */
137 void ceph_zero_page_vector_range(int off, int 169 void ceph_zero_page_vector_range(int off, int len, struct page **pages)
138 { 170 {
139 int i = off >> PAGE_SHIFT; 171 int i = off >> PAGE_SHIFT;
140 172
141 off &= ~PAGE_MASK; 173 off &= ~PAGE_MASK;
142 174
143 dout("zero_page_vector_page %u~%u\n", 175 dout("zero_page_vector_page %u~%u\n", off, len);
144 176
145 /* leading partial page? */ 177 /* leading partial page? */
146 if (off) { 178 if (off) {
147 int end = min((int)PAGE_SIZE, 179 int end = min((int)PAGE_SIZE, off + len);
148 dout("zeroing %d %p head from 180 dout("zeroing %d %p head from %d\n", i, pages[i],
149 (int)off); 181 (int)off);
150 zero_user_segment(pages[i], of 182 zero_user_segment(pages[i], off, end);
151 len -= (end - off); 183 len -= (end - off);
152 i++; 184 i++;
153 } 185 }
154 while (len >= PAGE_SIZE) { 186 while (len >= PAGE_SIZE) {
155 dout("zeroing %d %p len=%d\n", 187 dout("zeroing %d %p len=%d\n", i, pages[i], len);
156 zero_user_segment(pages[i], 0, 188 zero_user_segment(pages[i], 0, PAGE_SIZE);
157 len -= PAGE_SIZE; 189 len -= PAGE_SIZE;
158 i++; 190 i++;
159 } 191 }
160 /* trailing partial page? */ 192 /* trailing partial page? */
161 if (len) { 193 if (len) {
162 dout("zeroing %d %p tail to %d 194 dout("zeroing %d %p tail to %d\n", i, pages[i], (int)len);
163 zero_user_segment(pages[i], 0, 195 zero_user_segment(pages[i], 0, len);
164 } 196 }
165 } 197 }
166 EXPORT_SYMBOL(ceph_zero_page_vector_range); 198 EXPORT_SYMBOL(ceph_zero_page_vector_range);
>> 199
167 200
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