Commit | Line | Data |
---|---|---|
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> | |
20 | #include <asm/uaccess.h> | |
21 | ||
22 | #include <linux/coda.h> | |
23 | #include <linux/coda_linux.h> | |
24 | #include <linux/coda_fs_i.h> | |
25 | #include <linux/coda_psdev.h> | |
1da177e4 | 26 | |
c98d8cfb AB |
27 | #include "coda_int.h" |
28 | ||
1da177e4 LT |
29 | static ssize_t |
30 | coda_file_read(struct file *coda_file, char __user *buf, size_t count, loff_t *ppos) | |
31 | { | |
32 | struct coda_file_info *cfi; | |
33 | struct file *host_file; | |
34 | ||
35 | cfi = CODA_FTOC(coda_file); | |
36 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
37 | host_file = cfi->cfi_container; | |
38 | ||
39 | if (!host_file->f_op || !host_file->f_op->read) | |
40 | return -EINVAL; | |
41 | ||
42 | return host_file->f_op->read(host_file, buf, count, ppos); | |
43 | } | |
44 | ||
45 | static ssize_t | |
5ffc4ef4 JA |
46 | coda_file_splice_read(struct file *coda_file, loff_t *ppos, |
47 | struct pipe_inode_info *pipe, size_t count, | |
48 | unsigned int flags) | |
1da177e4 LT |
49 | { |
50 | struct coda_file_info *cfi; | |
51 | struct file *host_file; | |
52 | ||
53 | cfi = CODA_FTOC(coda_file); | |
54 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
55 | host_file = cfi->cfi_container; | |
56 | ||
5ffc4ef4 | 57 | if (!host_file->f_op || !host_file->f_op->splice_read) |
1da177e4 LT |
58 | return -EINVAL; |
59 | ||
5ffc4ef4 | 60 | return host_file->f_op->splice_read(host_file, ppos, pipe, count,flags); |
1da177e4 LT |
61 | } |
62 | ||
63 | static ssize_t | |
64 | coda_file_write(struct file *coda_file, const char __user *buf, size_t count, loff_t *ppos) | |
65 | { | |
d4176d32 | 66 | struct inode *host_inode, *coda_inode = coda_file->f_path.dentry->d_inode; |
1da177e4 LT |
67 | struct coda_file_info *cfi; |
68 | struct file *host_file; | |
69 | ssize_t ret; | |
70 | ||
71 | cfi = CODA_FTOC(coda_file); | |
72 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
73 | host_file = cfi->cfi_container; | |
74 | ||
75 | if (!host_file->f_op || !host_file->f_op->write) | |
76 | return -EINVAL; | |
77 | ||
d4176d32 | 78 | host_inode = host_file->f_path.dentry->d_inode; |
1b1dcc1b | 79 | mutex_lock(&coda_inode->i_mutex); |
1da177e4 LT |
80 | |
81 | ret = host_file->f_op->write(host_file, buf, count, ppos); | |
82 | ||
83 | coda_inode->i_size = host_inode->i_size; | |
84 | coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9; | |
85 | coda_inode->i_mtime = coda_inode->i_ctime = CURRENT_TIME_SEC; | |
1b1dcc1b | 86 | mutex_unlock(&coda_inode->i_mutex); |
1da177e4 LT |
87 | |
88 | return ret; | |
89 | } | |
90 | ||
91 | static int | |
92 | coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma) | |
93 | { | |
94 | struct coda_file_info *cfi; | |
95 | struct coda_inode_info *cii; | |
96 | struct file *host_file; | |
97 | struct inode *coda_inode, *host_inode; | |
98 | ||
99 | cfi = CODA_FTOC(coda_file); | |
100 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
101 | host_file = cfi->cfi_container; | |
102 | ||
103 | if (!host_file->f_op || !host_file->f_op->mmap) | |
104 | return -ENODEV; | |
105 | ||
d4176d32 JS |
106 | coda_inode = coda_file->f_path.dentry->d_inode; |
107 | host_inode = host_file->f_path.dentry->d_inode; | |
1da177e4 LT |
108 | coda_file->f_mapping = host_file->f_mapping; |
109 | if (coda_inode->i_mapping == &coda_inode->i_data) | |
110 | coda_inode->i_mapping = host_inode->i_mapping; | |
111 | ||
112 | /* only allow additional mmaps as long as userspace isn't changing | |
113 | * the container file on us! */ | |
114 | else if (coda_inode->i_mapping != host_inode->i_mapping) | |
115 | return -EBUSY; | |
116 | ||
117 | /* keep track of how often the coda_inode/host_file has been mmapped */ | |
118 | cii = ITOC(coda_inode); | |
119 | cii->c_mapcount++; | |
120 | cfi->cfi_mapcount++; | |
121 | ||
122 | return host_file->f_op->mmap(host_file, vma); | |
123 | } | |
124 | ||
125 | int coda_open(struct inode *coda_inode, struct file *coda_file) | |
126 | { | |
127 | struct file *host_file = NULL; | |
128 | int error; | |
129 | unsigned short flags = coda_file->f_flags & (~O_EXCL); | |
130 | unsigned short coda_flags = coda_flags_to_cflags(flags); | |
131 | struct coda_file_info *cfi; | |
132 | ||
1da177e4 | 133 | cfi = kmalloc(sizeof(struct coda_file_info), GFP_KERNEL); |
6ecbc4e1 | 134 | if (!cfi) |
1da177e4 | 135 | return -ENOMEM; |
1da177e4 LT |
136 | |
137 | lock_kernel(); | |
138 | ||
139 | error = venus_open(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags, | |
38c2e437 JH |
140 | &host_file); |
141 | if (!host_file) | |
142 | error = -EIO; | |
143 | ||
144 | if (error) { | |
1da177e4 LT |
145 | kfree(cfi); |
146 | unlock_kernel(); | |
147 | return error; | |
148 | } | |
149 | ||
150 | host_file->f_flags |= coda_file->f_flags & (O_APPEND | O_SYNC); | |
151 | ||
152 | cfi->cfi_magic = CODA_MAGIC; | |
153 | cfi->cfi_mapcount = 0; | |
154 | cfi->cfi_container = host_file; | |
155 | ||
156 | BUG_ON(coda_file->private_data != NULL); | |
157 | coda_file->private_data = cfi; | |
158 | ||
159 | unlock_kernel(); | |
160 | return 0; | |
161 | } | |
162 | ||
1da177e4 LT |
163 | int coda_release(struct inode *coda_inode, struct file *coda_file) |
164 | { | |
165 | unsigned short flags = (coda_file->f_flags) & (~O_EXCL); | |
166 | unsigned short coda_flags = coda_flags_to_cflags(flags); | |
167 | struct coda_file_info *cfi; | |
168 | struct coda_inode_info *cii; | |
169 | struct inode *host_inode; | |
170 | int err = 0; | |
171 | ||
172 | lock_kernel(); | |
3cf01f28 | 173 | |
1da177e4 LT |
174 | cfi = CODA_FTOC(coda_file); |
175 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
176 | ||
d3fec424 | 177 | err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode), |
d76b0d9b | 178 | coda_flags, coda_file->f_cred->fsuid); |
1da177e4 | 179 | |
d4176d32 | 180 | host_inode = cfi->cfi_container->f_path.dentry->d_inode; |
1da177e4 LT |
181 | cii = ITOC(coda_inode); |
182 | ||
183 | /* did we mmap this file? */ | |
184 | if (coda_inode->i_mapping == &host_inode->i_data) { | |
185 | cii->c_mapcount -= cfi->cfi_mapcount; | |
186 | if (!cii->c_mapcount) | |
187 | coda_inode->i_mapping = &coda_inode->i_data; | |
188 | } | |
189 | ||
190 | fput(cfi->cfi_container); | |
191 | kfree(coda_file->private_data); | |
192 | coda_file->private_data = NULL; | |
193 | ||
194 | unlock_kernel(); | |
d3fec424 JH |
195 | |
196 | /* VFS fput ignores the return value from file_operations->release, so | |
197 | * there is no use returning an error here */ | |
198 | return 0; | |
1da177e4 LT |
199 | } |
200 | ||
201 | int coda_fsync(struct file *coda_file, struct dentry *coda_dentry, int datasync) | |
202 | { | |
203 | struct file *host_file; | |
204 | struct dentry *host_dentry; | |
205 | struct inode *host_inode, *coda_inode = coda_dentry->d_inode; | |
206 | struct coda_file_info *cfi; | |
207 | int err = 0; | |
208 | ||
209 | if (!(S_ISREG(coda_inode->i_mode) || S_ISDIR(coda_inode->i_mode) || | |
210 | S_ISLNK(coda_inode->i_mode))) | |
211 | return -EINVAL; | |
212 | ||
213 | cfi = CODA_FTOC(coda_file); | |
214 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
215 | host_file = cfi->cfi_container; | |
216 | ||
1da177e4 | 217 | if (host_file->f_op && host_file->f_op->fsync) { |
d4176d32 | 218 | host_dentry = host_file->f_path.dentry; |
1da177e4 | 219 | host_inode = host_dentry->d_inode; |
1b1dcc1b | 220 | mutex_lock(&host_inode->i_mutex); |
1da177e4 | 221 | err = host_file->f_op->fsync(host_file, host_dentry, datasync); |
1b1dcc1b | 222 | mutex_unlock(&host_inode->i_mutex); |
1da177e4 LT |
223 | } |
224 | ||
225 | if ( !err && !datasync ) { | |
226 | lock_kernel(); | |
227 | err = venus_fsync(coda_inode->i_sb, coda_i2f(coda_inode)); | |
228 | unlock_kernel(); | |
229 | } | |
230 | ||
231 | return err; | |
232 | } | |
233 | ||
4b6f5d20 | 234 | const struct file_operations coda_file_operations = { |
1da177e4 LT |
235 | .llseek = generic_file_llseek, |
236 | .read = coda_file_read, | |
237 | .write = coda_file_write, | |
238 | .mmap = coda_file_mmap, | |
239 | .open = coda_open, | |
1da177e4 LT |
240 | .release = coda_release, |
241 | .fsync = coda_fsync, | |
5ffc4ef4 | 242 | .splice_read = coda_file_splice_read, |
1da177e4 LT |
243 | }; |
244 |