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Commit | Line | Data |
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3d14c5d2 YS |
1 | #include <linux/ceph/ceph_debug.h> |
2 | ||
3 | #include <linux/module.h> | |
4 | #include <linux/sched.h> | |
5 | #include <linux/slab.h> | |
6 | #include <linux/file.h> | |
7 | #include <linux/namei.h> | |
8 | #include <linux/writeback.h> | |
9 | ||
10 | #include <linux/ceph/libceph.h> | |
11 | ||
12 | /* | |
13 | * build a vector of user pages | |
14 | */ | |
b324814e | 15 | struct page **ceph_get_direct_page_vector(const void __user *data, |
b6aa5901 | 16 | int num_pages, bool write_page) |
3d14c5d2 YS |
17 | { |
18 | struct page **pages; | |
38815b78 SW |
19 | int got = 0; |
20 | int rc = 0; | |
3d14c5d2 YS |
21 | |
22 | pages = kmalloc(sizeof(*pages) * num_pages, GFP_NOFS); | |
23 | if (!pages) | |
24 | return ERR_PTR(-ENOMEM); | |
25 | ||
38815b78 | 26 | while (got < num_pages) { |
7e339128 | 27 | rc = get_user_pages_unlocked(current, current->mm, |
38815b78 | 28 | (unsigned long)data + ((unsigned long)got * PAGE_SIZE), |
7e339128 | 29 | num_pages - got, write_page, 0, pages + got); |
38815b78 SW |
30 | if (rc < 0) |
31 | break; | |
32 | BUG_ON(rc == 0); | |
33 | got += rc; | |
34 | } | |
38815b78 | 35 | if (rc < 0) |
3d14c5d2 YS |
36 | goto fail; |
37 | return pages; | |
38 | ||
39 | fail: | |
38815b78 | 40 | ceph_put_page_vector(pages, got, false); |
3d14c5d2 YS |
41 | return ERR_PTR(rc); |
42 | } | |
43 | EXPORT_SYMBOL(ceph_get_direct_page_vector); | |
44 | ||
b6aa5901 | 45 | void ceph_put_page_vector(struct page **pages, int num_pages, bool dirty) |
3d14c5d2 YS |
46 | { |
47 | int i; | |
48 | ||
b6aa5901 HC |
49 | for (i = 0; i < num_pages; i++) { |
50 | if (dirty) | |
51 | set_page_dirty_lock(pages[i]); | |
3d14c5d2 | 52 | put_page(pages[i]); |
b6aa5901 | 53 | } |
2b777c9d AV |
54 | if (is_vmalloc_addr(pages)) |
55 | vfree(pages); | |
56 | else | |
57 | kfree(pages); | |
3d14c5d2 YS |
58 | } |
59 | EXPORT_SYMBOL(ceph_put_page_vector); | |
60 | ||
61 | void ceph_release_page_vector(struct page **pages, int num_pages) | |
62 | { | |
63 | int i; | |
64 | ||
65 | for (i = 0; i < num_pages; i++) | |
66 | __free_pages(pages[i], 0); | |
67 | kfree(pages); | |
68 | } | |
69 | EXPORT_SYMBOL(ceph_release_page_vector); | |
70 | ||
71 | /* | |
72 | * allocate a vector new pages | |
73 | */ | |
74 | struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags) | |
75 | { | |
76 | struct page **pages; | |
77 | int i; | |
78 | ||
79 | pages = kmalloc(sizeof(*pages) * num_pages, flags); | |
80 | if (!pages) | |
81 | return ERR_PTR(-ENOMEM); | |
82 | for (i = 0; i < num_pages; i++) { | |
83 | pages[i] = __page_cache_alloc(flags); | |
84 | if (pages[i] == NULL) { | |
85 | ceph_release_page_vector(pages, i); | |
86 | return ERR_PTR(-ENOMEM); | |
87 | } | |
88 | } | |
89 | return pages; | |
90 | } | |
91 | EXPORT_SYMBOL(ceph_alloc_page_vector); | |
92 | ||
93 | /* | |
94 | * copy user data into a page vector | |
95 | */ | |
96 | int ceph_copy_user_to_page_vector(struct page **pages, | |
b324814e | 97 | const void __user *data, |
3d14c5d2 YS |
98 | loff_t off, size_t len) |
99 | { | |
100 | int i = 0; | |
101 | int po = off & ~PAGE_CACHE_MASK; | |
102 | int left = len; | |
103 | int l, bad; | |
104 | ||
105 | while (left > 0) { | |
106 | l = min_t(int, PAGE_CACHE_SIZE-po, left); | |
107 | bad = copy_from_user(page_address(pages[i]) + po, data, l); | |
108 | if (bad == l) | |
109 | return -EFAULT; | |
110 | data += l - bad; | |
111 | left -= l - bad; | |
112 | po += l - bad; | |
113 | if (po == PAGE_CACHE_SIZE) { | |
114 | po = 0; | |
115 | i++; | |
116 | } | |
117 | } | |
118 | return len; | |
119 | } | |
120 | EXPORT_SYMBOL(ceph_copy_user_to_page_vector); | |
121 | ||
903bb32e | 122 | void ceph_copy_to_page_vector(struct page **pages, |
b324814e | 123 | const void *data, |
3d14c5d2 YS |
124 | loff_t off, size_t len) |
125 | { | |
126 | int i = 0; | |
127 | size_t po = off & ~PAGE_CACHE_MASK; | |
128 | size_t left = len; | |
3d14c5d2 YS |
129 | |
130 | while (left > 0) { | |
903bb32e AE |
131 | size_t l = min_t(size_t, PAGE_CACHE_SIZE-po, left); |
132 | ||
3d14c5d2 YS |
133 | memcpy(page_address(pages[i]) + po, data, l); |
134 | data += l; | |
135 | left -= l; | |
136 | po += l; | |
137 | if (po == PAGE_CACHE_SIZE) { | |
138 | po = 0; | |
139 | i++; | |
140 | } | |
141 | } | |
3d14c5d2 YS |
142 | } |
143 | EXPORT_SYMBOL(ceph_copy_to_page_vector); | |
144 | ||
903bb32e | 145 | void ceph_copy_from_page_vector(struct page **pages, |
b324814e | 146 | void *data, |
3d14c5d2 YS |
147 | loff_t off, size_t len) |
148 | { | |
149 | int i = 0; | |
150 | size_t po = off & ~PAGE_CACHE_MASK; | |
151 | size_t left = len; | |
3d14c5d2 YS |
152 | |
153 | while (left > 0) { | |
903bb32e AE |
154 | size_t l = min_t(size_t, PAGE_CACHE_SIZE-po, left); |
155 | ||
3d14c5d2 YS |
156 | memcpy(data, page_address(pages[i]) + po, l); |
157 | data += l; | |
158 | left -= l; | |
159 | po += l; | |
160 | if (po == PAGE_CACHE_SIZE) { | |
161 | po = 0; | |
162 | i++; | |
163 | } | |
164 | } | |
3d14c5d2 YS |
165 | } |
166 | EXPORT_SYMBOL(ceph_copy_from_page_vector); | |
167 | ||
3d14c5d2 YS |
168 | /* |
169 | * Zero an extent within a page vector. Offset is relative to the | |
170 | * start of the first page. | |
171 | */ | |
172 | void ceph_zero_page_vector_range(int off, int len, struct page **pages) | |
173 | { | |
174 | int i = off >> PAGE_CACHE_SHIFT; | |
175 | ||
176 | off &= ~PAGE_CACHE_MASK; | |
177 | ||
178 | dout("zero_page_vector_page %u~%u\n", off, len); | |
179 | ||
180 | /* leading partial page? */ | |
181 | if (off) { | |
182 | int end = min((int)PAGE_CACHE_SIZE, off + len); | |
183 | dout("zeroing %d %p head from %d\n", i, pages[i], | |
184 | (int)off); | |
185 | zero_user_segment(pages[i], off, end); | |
186 | len -= (end - off); | |
187 | i++; | |
188 | } | |
189 | while (len >= PAGE_CACHE_SIZE) { | |
190 | dout("zeroing %d %p len=%d\n", i, pages[i], len); | |
191 | zero_user_segment(pages[i], 0, PAGE_CACHE_SIZE); | |
192 | len -= PAGE_CACHE_SIZE; | |
193 | i++; | |
194 | } | |
195 | /* trailing partial page? */ | |
196 | if (len) { | |
197 | dout("zeroing %d %p tail to %d\n", i, pages[i], (int)len); | |
198 | zero_user_segment(pages[i], 0, len); | |
199 | } | |
200 | } | |
201 | EXPORT_SYMBOL(ceph_zero_page_vector_range); | |
202 |