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> | |
b5ce1d83 | 19 | #include <linux/spinlock.h> |
1da177e4 | 20 | #include <linux/string.h> |
5a0e3ad6 | 21 | #include <linux/slab.h> |
1da177e4 LT |
22 | #include <asm/uaccess.h> |
23 | ||
24 | #include <linux/coda.h> | |
25 | #include <linux/coda_linux.h> | |
26 | #include <linux/coda_fs_i.h> | |
27 | #include <linux/coda_psdev.h> | |
1da177e4 | 28 | |
c98d8cfb AB |
29 | #include "coda_int.h" |
30 | ||
1da177e4 LT |
31 | static ssize_t |
32 | coda_file_read(struct file *coda_file, char __user *buf, size_t count, loff_t *ppos) | |
33 | { | |
34 | struct coda_file_info *cfi; | |
35 | struct file *host_file; | |
36 | ||
37 | cfi = CODA_FTOC(coda_file); | |
38 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
39 | host_file = cfi->cfi_container; | |
40 | ||
41 | if (!host_file->f_op || !host_file->f_op->read) | |
42 | return -EINVAL; | |
43 | ||
44 | return host_file->f_op->read(host_file, buf, count, ppos); | |
45 | } | |
46 | ||
47 | static ssize_t | |
5ffc4ef4 JA |
48 | coda_file_splice_read(struct file *coda_file, loff_t *ppos, |
49 | struct pipe_inode_info *pipe, size_t count, | |
50 | unsigned int flags) | |
1da177e4 | 51 | { |
6818173b MS |
52 | ssize_t (*splice_read)(struct file *, loff_t *, |
53 | struct pipe_inode_info *, size_t, unsigned int); | |
1da177e4 LT |
54 | struct coda_file_info *cfi; |
55 | struct file *host_file; | |
56 | ||
57 | cfi = CODA_FTOC(coda_file); | |
58 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
59 | host_file = cfi->cfi_container; | |
60 | ||
6818173b MS |
61 | splice_read = host_file->f_op->splice_read; |
62 | if (!splice_read) | |
63 | splice_read = default_file_splice_read; | |
1da177e4 | 64 | |
6818173b | 65 | return splice_read(host_file, ppos, pipe, count, flags); |
1da177e4 LT |
66 | } |
67 | ||
68 | static ssize_t | |
69 | coda_file_write(struct file *coda_file, const char __user *buf, size_t count, loff_t *ppos) | |
70 | { | |
d4176d32 | 71 | struct inode *host_inode, *coda_inode = coda_file->f_path.dentry->d_inode; |
1da177e4 LT |
72 | struct coda_file_info *cfi; |
73 | struct file *host_file; | |
74 | ssize_t ret; | |
75 | ||
76 | cfi = CODA_FTOC(coda_file); | |
77 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
78 | host_file = cfi->cfi_container; | |
79 | ||
80 | if (!host_file->f_op || !host_file->f_op->write) | |
81 | return -EINVAL; | |
82 | ||
d4176d32 | 83 | host_inode = host_file->f_path.dentry->d_inode; |
1b1dcc1b | 84 | mutex_lock(&coda_inode->i_mutex); |
1da177e4 LT |
85 | |
86 | ret = host_file->f_op->write(host_file, buf, count, ppos); | |
87 | ||
88 | coda_inode->i_size = host_inode->i_size; | |
89 | coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9; | |
90 | coda_inode->i_mtime = coda_inode->i_ctime = CURRENT_TIME_SEC; | |
1b1dcc1b | 91 | mutex_unlock(&coda_inode->i_mutex); |
1da177e4 LT |
92 | |
93 | return ret; | |
94 | } | |
95 | ||
96 | static int | |
97 | coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma) | |
98 | { | |
99 | struct coda_file_info *cfi; | |
100 | struct coda_inode_info *cii; | |
101 | struct file *host_file; | |
102 | struct inode *coda_inode, *host_inode; | |
103 | ||
104 | cfi = CODA_FTOC(coda_file); | |
105 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
106 | host_file = cfi->cfi_container; | |
107 | ||
108 | if (!host_file->f_op || !host_file->f_op->mmap) | |
109 | return -ENODEV; | |
110 | ||
d4176d32 JS |
111 | coda_inode = coda_file->f_path.dentry->d_inode; |
112 | host_inode = host_file->f_path.dentry->d_inode; | |
b5ce1d83 YA |
113 | |
114 | cii = ITOC(coda_inode); | |
115 | spin_lock(&cii->c_lock); | |
1da177e4 LT |
116 | coda_file->f_mapping = host_file->f_mapping; |
117 | if (coda_inode->i_mapping == &coda_inode->i_data) | |
118 | coda_inode->i_mapping = host_inode->i_mapping; | |
119 | ||
120 | /* only allow additional mmaps as long as userspace isn't changing | |
121 | * the container file on us! */ | |
b5ce1d83 YA |
122 | else if (coda_inode->i_mapping != host_inode->i_mapping) { |
123 | spin_unlock(&cii->c_lock); | |
1da177e4 | 124 | return -EBUSY; |
b5ce1d83 | 125 | } |
1da177e4 LT |
126 | |
127 | /* keep track of how often the coda_inode/host_file has been mmapped */ | |
1da177e4 LT |
128 | cii->c_mapcount++; |
129 | cfi->cfi_mapcount++; | |
b5ce1d83 | 130 | spin_unlock(&cii->c_lock); |
1da177e4 LT |
131 | |
132 | return host_file->f_op->mmap(host_file, vma); | |
133 | } | |
134 | ||
135 | int coda_open(struct inode *coda_inode, struct file *coda_file) | |
136 | { | |
137 | struct file *host_file = NULL; | |
138 | int error; | |
139 | unsigned short flags = coda_file->f_flags & (~O_EXCL); | |
140 | unsigned short coda_flags = coda_flags_to_cflags(flags); | |
141 | struct coda_file_info *cfi; | |
142 | ||
1da177e4 | 143 | cfi = kmalloc(sizeof(struct coda_file_info), GFP_KERNEL); |
6ecbc4e1 | 144 | if (!cfi) |
1da177e4 | 145 | return -ENOMEM; |
1da177e4 LT |
146 | |
147 | lock_kernel(); | |
148 | ||
149 | error = venus_open(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags, | |
38c2e437 JH |
150 | &host_file); |
151 | if (!host_file) | |
152 | error = -EIO; | |
153 | ||
154 | if (error) { | |
1da177e4 LT |
155 | kfree(cfi); |
156 | unlock_kernel(); | |
157 | return error; | |
158 | } | |
159 | ||
160 | host_file->f_flags |= coda_file->f_flags & (O_APPEND | O_SYNC); | |
161 | ||
162 | cfi->cfi_magic = CODA_MAGIC; | |
163 | cfi->cfi_mapcount = 0; | |
164 | cfi->cfi_container = host_file; | |
165 | ||
166 | BUG_ON(coda_file->private_data != NULL); | |
167 | coda_file->private_data = cfi; | |
168 | ||
169 | unlock_kernel(); | |
170 | return 0; | |
171 | } | |
172 | ||
1da177e4 LT |
173 | int coda_release(struct inode *coda_inode, struct file *coda_file) |
174 | { | |
175 | unsigned short flags = (coda_file->f_flags) & (~O_EXCL); | |
176 | unsigned short coda_flags = coda_flags_to_cflags(flags); | |
177 | struct coda_file_info *cfi; | |
178 | struct coda_inode_info *cii; | |
179 | struct inode *host_inode; | |
180 | int err = 0; | |
181 | ||
182 | lock_kernel(); | |
3cf01f28 | 183 | |
1da177e4 LT |
184 | cfi = CODA_FTOC(coda_file); |
185 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
186 | ||
d3fec424 | 187 | err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode), |
d76b0d9b | 188 | coda_flags, coda_file->f_cred->fsuid); |
1da177e4 | 189 | |
d4176d32 | 190 | host_inode = cfi->cfi_container->f_path.dentry->d_inode; |
1da177e4 LT |
191 | cii = ITOC(coda_inode); |
192 | ||
193 | /* did we mmap this file? */ | |
b5ce1d83 | 194 | spin_lock(&cii->c_lock); |
1da177e4 LT |
195 | if (coda_inode->i_mapping == &host_inode->i_data) { |
196 | cii->c_mapcount -= cfi->cfi_mapcount; | |
197 | if (!cii->c_mapcount) | |
198 | coda_inode->i_mapping = &coda_inode->i_data; | |
199 | } | |
b5ce1d83 | 200 | spin_unlock(&cii->c_lock); |
1da177e4 LT |
201 | |
202 | fput(cfi->cfi_container); | |
203 | kfree(coda_file->private_data); | |
204 | coda_file->private_data = NULL; | |
205 | ||
206 | unlock_kernel(); | |
d3fec424 JH |
207 | |
208 | /* VFS fput ignores the return value from file_operations->release, so | |
209 | * there is no use returning an error here */ | |
210 | return 0; | |
1da177e4 LT |
211 | } |
212 | ||
7ea80859 | 213 | int coda_fsync(struct file *coda_file, int datasync) |
1da177e4 LT |
214 | { |
215 | struct file *host_file; | |
7ea80859 | 216 | struct inode *coda_inode = coda_file->f_path.dentry->d_inode; |
1da177e4 LT |
217 | struct coda_file_info *cfi; |
218 | int err = 0; | |
219 | ||
220 | if (!(S_ISREG(coda_inode->i_mode) || S_ISDIR(coda_inode->i_mode) || | |
221 | S_ISLNK(coda_inode->i_mode))) | |
222 | return -EINVAL; | |
223 | ||
224 | cfi = CODA_FTOC(coda_file); | |
225 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); | |
226 | host_file = cfi->cfi_container; | |
227 | ||
8018ab05 | 228 | err = vfs_fsync(host_file, datasync); |
1da177e4 LT |
229 | if ( !err && !datasync ) { |
230 | lock_kernel(); | |
231 | err = venus_fsync(coda_inode->i_sb, coda_i2f(coda_inode)); | |
232 | unlock_kernel(); | |
233 | } | |
234 | ||
235 | return err; | |
236 | } | |
237 | ||
4b6f5d20 | 238 | const struct file_operations coda_file_operations = { |
1da177e4 LT |
239 | .llseek = generic_file_llseek, |
240 | .read = coda_file_read, | |
241 | .write = coda_file_write, | |
242 | .mmap = coda_file_mmap, | |
243 | .open = coda_open, | |
1da177e4 LT |
244 | .release = coda_release, |
245 | .fsync = coda_fsync, | |
5ffc4ef4 | 246 | .splice_read = coda_file_splice_read, |
1da177e4 LT |
247 | }; |
248 |