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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * File operations for Coda. | |
3 | * Original version: (C) 1996 Peter Braam | |
4 | * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University | |
5 | * | |
6 | * Carnegie Mellon encourages users of this code to contribute improvements | |
7 | * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>. | |
8 | */ | |
9 | ||
10 | #include <linux/types.h> | |
11 | #include <linux/kernel.h> | |
12 | #include <linux/time.h> | |
13 | #include <linux/file.h> | |
14 | #include <linux/fs.h> | |
15 | #include <linux/stat.h> | |
7596b27d | 16 | #include <linux/cred.h> |
1da177e4 LT |
17 | #include <linux/errno.h> |
18 | #include <linux/smp_lock.h> | |
19 | #include <linux/string.h> | |
5a0e3ad6 | 20 | #include <linux/slab.h> |
1da177e4 LT |
21 | #include <asm/uaccess.h> |
22 | ||
23 | #include <linux/coda.h> | |
24 | #include <linux/coda_linux.h> | |
25 | #include <linux/coda_fs_i.h> | |
26 | #include <linux/coda_psdev.h> | |
1da177e4 | 27 | |
c98d8cfb AB |
28 | #include "coda_int.h" |
29 | ||
1da177e4 LT |
30 | static ssize_t |
31 | coda_file_read(struct file *coda_file, char __user *buf, size_t count, loff_t *ppos) | |
32 | { | |
33 | struct coda_file_info *cfi; | |
34 | struct file *host_file; | |
35 | ||
36 | cfi = CODA_FTOC(coda_file); | |
37 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
38 | host_file = cfi->cfi_container; | |
39 | ||
40 | if (!host_file->f_op || !host_file->f_op->read) | |
41 | return -EINVAL; | |
42 | ||
43 | return host_file->f_op->read(host_file, buf, count, ppos); | |
44 | } | |
45 | ||
46 | static ssize_t | |
5ffc4ef4 JA |
47 | coda_file_splice_read(struct file *coda_file, loff_t *ppos, |
48 | struct pipe_inode_info *pipe, size_t count, | |
49 | unsigned int flags) | |
1da177e4 | 50 | { |
6818173b MS |
51 | ssize_t (*splice_read)(struct file *, loff_t *, |
52 | struct pipe_inode_info *, size_t, unsigned int); | |
1da177e4 LT |
53 | struct coda_file_info *cfi; |
54 | struct file *host_file; | |
55 | ||
56 | cfi = CODA_FTOC(coda_file); | |
57 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
58 | host_file = cfi->cfi_container; | |
59 | ||
6818173b MS |
60 | splice_read = host_file->f_op->splice_read; |
61 | if (!splice_read) | |
62 | splice_read = default_file_splice_read; | |
1da177e4 | 63 | |
6818173b | 64 | return splice_read(host_file, ppos, pipe, count, flags); |
1da177e4 LT |
65 | } |
66 | ||
67 | static ssize_t | |
68 | coda_file_write(struct file *coda_file, const char __user *buf, size_t count, loff_t *ppos) | |
69 | { | |
d4176d32 | 70 | struct inode *host_inode, *coda_inode = coda_file->f_path.dentry->d_inode; |
1da177e4 LT |
71 | struct coda_file_info *cfi; |
72 | struct file *host_file; | |
73 | ssize_t ret; | |
74 | ||
75 | cfi = CODA_FTOC(coda_file); | |
76 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
77 | host_file = cfi->cfi_container; | |
78 | ||
79 | if (!host_file->f_op || !host_file->f_op->write) | |
80 | return -EINVAL; | |
81 | ||
d4176d32 | 82 | host_inode = host_file->f_path.dentry->d_inode; |
1b1dcc1b | 83 | mutex_lock(&coda_inode->i_mutex); |
1da177e4 LT |
84 | |
85 | ret = host_file->f_op->write(host_file, buf, count, ppos); | |
86 | ||
87 | coda_inode->i_size = host_inode->i_size; | |
88 | coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9; | |
89 | coda_inode->i_mtime = coda_inode->i_ctime = CURRENT_TIME_SEC; | |
1b1dcc1b | 90 | mutex_unlock(&coda_inode->i_mutex); |
1da177e4 LT |
91 | |
92 | return ret; | |
93 | } | |
94 | ||
95 | static int | |
96 | coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma) | |
97 | { | |
98 | struct coda_file_info *cfi; | |
99 | struct coda_inode_info *cii; | |
100 | struct file *host_file; | |
101 | struct inode *coda_inode, *host_inode; | |
102 | ||
103 | cfi = CODA_FTOC(coda_file); | |
104 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
105 | host_file = cfi->cfi_container; | |
106 | ||
107 | if (!host_file->f_op || !host_file->f_op->mmap) | |
108 | return -ENODEV; | |
109 | ||
d4176d32 JS |
110 | coda_inode = coda_file->f_path.dentry->d_inode; |
111 | host_inode = host_file->f_path.dentry->d_inode; | |
1da177e4 LT |
112 | coda_file->f_mapping = host_file->f_mapping; |
113 | if (coda_inode->i_mapping == &coda_inode->i_data) | |
114 | coda_inode->i_mapping = host_inode->i_mapping; | |
115 | ||
116 | /* only allow additional mmaps as long as userspace isn't changing | |
117 | * the container file on us! */ | |
118 | else if (coda_inode->i_mapping != host_inode->i_mapping) | |
119 | return -EBUSY; | |
120 | ||
121 | /* keep track of how often the coda_inode/host_file has been mmapped */ | |
122 | cii = ITOC(coda_inode); | |
123 | cii->c_mapcount++; | |
124 | cfi->cfi_mapcount++; | |
125 | ||
126 | return host_file->f_op->mmap(host_file, vma); | |
127 | } | |
128 | ||
129 | int coda_open(struct inode *coda_inode, struct file *coda_file) | |
130 | { | |
131 | struct file *host_file = NULL; | |
132 | int error; | |
133 | unsigned short flags = coda_file->f_flags & (~O_EXCL); | |
134 | unsigned short coda_flags = coda_flags_to_cflags(flags); | |
135 | struct coda_file_info *cfi; | |
136 | ||
1da177e4 | 137 | cfi = kmalloc(sizeof(struct coda_file_info), GFP_KERNEL); |
6ecbc4e1 | 138 | if (!cfi) |
1da177e4 | 139 | return -ENOMEM; |
1da177e4 LT |
140 | |
141 | lock_kernel(); | |
142 | ||
143 | error = venus_open(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags, | |
38c2e437 JH |
144 | &host_file); |
145 | if (!host_file) | |
146 | error = -EIO; | |
147 | ||
148 | if (error) { | |
1da177e4 LT |
149 | kfree(cfi); |
150 | unlock_kernel(); | |
151 | return error; | |
152 | } | |
153 | ||
154 | host_file->f_flags |= coda_file->f_flags & (O_APPEND | O_SYNC); | |
155 | ||
156 | cfi->cfi_magic = CODA_MAGIC; | |
157 | cfi->cfi_mapcount = 0; | |
158 | cfi->cfi_container = host_file; | |
159 | ||
160 | BUG_ON(coda_file->private_data != NULL); | |
161 | coda_file->private_data = cfi; | |
162 | ||
163 | unlock_kernel(); | |
164 | return 0; | |
165 | } | |
166 | ||
1da177e4 LT |
167 | int coda_release(struct inode *coda_inode, struct file *coda_file) |
168 | { | |
169 | unsigned short flags = (coda_file->f_flags) & (~O_EXCL); | |
170 | unsigned short coda_flags = coda_flags_to_cflags(flags); | |
171 | struct coda_file_info *cfi; | |
172 | struct coda_inode_info *cii; | |
173 | struct inode *host_inode; | |
174 | int err = 0; | |
175 | ||
176 | lock_kernel(); | |
3cf01f28 | 177 | |
1da177e4 LT |
178 | cfi = CODA_FTOC(coda_file); |
179 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
180 | ||
d3fec424 | 181 | err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode), |
d76b0d9b | 182 | coda_flags, coda_file->f_cred->fsuid); |
1da177e4 | 183 | |
d4176d32 | 184 | host_inode = cfi->cfi_container->f_path.dentry->d_inode; |
1da177e4 LT |
185 | cii = ITOC(coda_inode); |
186 | ||
187 | /* did we mmap this file? */ | |
188 | if (coda_inode->i_mapping == &host_inode->i_data) { | |
189 | cii->c_mapcount -= cfi->cfi_mapcount; | |
190 | if (!cii->c_mapcount) | |
191 | coda_inode->i_mapping = &coda_inode->i_data; | |
192 | } | |
193 | ||
194 | fput(cfi->cfi_container); | |
195 | kfree(coda_file->private_data); | |
196 | coda_file->private_data = NULL; | |
197 | ||
198 | unlock_kernel(); | |
d3fec424 JH |
199 | |
200 | /* VFS fput ignores the return value from file_operations->release, so | |
201 | * there is no use returning an error here */ | |
202 | return 0; | |
1da177e4 LT |
203 | } |
204 | ||
7ea80859 | 205 | int coda_fsync(struct file *coda_file, int datasync) |
1da177e4 LT |
206 | { |
207 | struct file *host_file; | |
7ea80859 | 208 | struct inode *coda_inode = coda_file->f_path.dentry->d_inode; |
1da177e4 LT |
209 | struct coda_file_info *cfi; |
210 | int err = 0; | |
211 | ||
212 | if (!(S_ISREG(coda_inode->i_mode) || S_ISDIR(coda_inode->i_mode) || | |
213 | S_ISLNK(coda_inode->i_mode))) | |
214 | return -EINVAL; | |
215 | ||
216 | cfi = CODA_FTOC(coda_file); | |
217 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
218 | host_file = cfi->cfi_container; | |
219 | ||
8018ab05 | 220 | err = vfs_fsync(host_file, datasync); |
1da177e4 LT |
221 | if ( !err && !datasync ) { |
222 | lock_kernel(); | |
223 | err = venus_fsync(coda_inode->i_sb, coda_i2f(coda_inode)); | |
224 | unlock_kernel(); | |
225 | } | |
226 | ||
227 | return err; | |
228 | } | |
229 | ||
4b6f5d20 | 230 | const struct file_operations coda_file_operations = { |
1da177e4 LT |
231 | .llseek = generic_file_llseek, |
232 | .read = coda_file_read, | |
233 | .write = coda_file_write, | |
234 | .mmap = coda_file_mmap, | |
235 | .open = coda_open, | |
1da177e4 LT |
236 | .release = coda_release, |
237 | .fsync = coda_fsync, | |
5ffc4ef4 | 238 | .splice_read = coda_file_splice_read, |
1da177e4 LT |
239 | }; |
240 |