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