Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
| 16 | #include <linux/errno.h> |
| 17 | #include <linux/smp_lock.h> |
| 18 | #include <linux/string.h> |
| 19 | #include <asm/uaccess.h> |
| 20 | |
| 21 | #include <linux/coda.h> |
| 22 | #include <linux/coda_linux.h> |
| 23 | #include <linux/coda_fs_i.h> |
| 24 | #include <linux/coda_psdev.h> |
| 25 | #include <linux/coda_proc.h> |
| 26 | |
Adrian Bunk | c98d8cf | 2006-03-24 03:15:53 -0800 | [diff] [blame] | 27 | #include "coda_int.h" |
| 28 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | /* if CODA_STORE fails with EOPNOTSUPP, venus clearly doesn't support |
| 30 | * CODA_STORE/CODA_RELEASE and we fall back on using the CODA_CLOSE upcall */ |
| 31 | static int use_coda_close; |
| 32 | |
| 33 | static ssize_t |
| 34 | coda_file_read(struct file *coda_file, char __user *buf, size_t count, loff_t *ppos) |
| 35 | { |
| 36 | struct coda_file_info *cfi; |
| 37 | struct file *host_file; |
| 38 | |
| 39 | cfi = CODA_FTOC(coda_file); |
| 40 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); |
| 41 | host_file = cfi->cfi_container; |
| 42 | |
| 43 | if (!host_file->f_op || !host_file->f_op->read) |
| 44 | return -EINVAL; |
| 45 | |
| 46 | return host_file->f_op->read(host_file, buf, count, ppos); |
| 47 | } |
| 48 | |
| 49 | static ssize_t |
| 50 | coda_file_sendfile(struct file *coda_file, loff_t *ppos, size_t count, |
| 51 | read_actor_t actor, void *target) |
| 52 | { |
| 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 | |
| 60 | if (!host_file->f_op || !host_file->f_op->sendfile) |
| 61 | return -EINVAL; |
| 62 | |
| 63 | return host_file->f_op->sendfile(host_file, ppos, count, actor, target); |
| 64 | } |
| 65 | |
| 66 | static ssize_t |
| 67 | coda_file_write(struct file *coda_file, const char __user *buf, size_t count, loff_t *ppos) |
| 68 | { |
Josef Sipek | d4176d3 | 2006-12-08 02:36:56 -0800 | [diff] [blame^] | 69 | struct inode *host_inode, *coda_inode = coda_file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | struct coda_file_info *cfi; |
| 71 | struct file *host_file; |
| 72 | ssize_t ret; |
| 73 | |
| 74 | cfi = CODA_FTOC(coda_file); |
| 75 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); |
| 76 | host_file = cfi->cfi_container; |
| 77 | |
| 78 | if (!host_file->f_op || !host_file->f_op->write) |
| 79 | return -EINVAL; |
| 80 | |
Josef Sipek | d4176d3 | 2006-12-08 02:36:56 -0800 | [diff] [blame^] | 81 | host_inode = host_file->f_path.dentry->d_inode; |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 82 | mutex_lock(&coda_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | |
| 84 | ret = host_file->f_op->write(host_file, buf, count, ppos); |
| 85 | |
| 86 | coda_inode->i_size = host_inode->i_size; |
| 87 | coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9; |
| 88 | coda_inode->i_mtime = coda_inode->i_ctime = CURRENT_TIME_SEC; |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 89 | mutex_unlock(&coda_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | |
| 91 | return ret; |
| 92 | } |
| 93 | |
| 94 | static int |
| 95 | coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma) |
| 96 | { |
| 97 | struct coda_file_info *cfi; |
| 98 | struct coda_inode_info *cii; |
| 99 | struct file *host_file; |
| 100 | struct inode *coda_inode, *host_inode; |
| 101 | |
| 102 | cfi = CODA_FTOC(coda_file); |
| 103 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); |
| 104 | host_file = cfi->cfi_container; |
| 105 | |
| 106 | if (!host_file->f_op || !host_file->f_op->mmap) |
| 107 | return -ENODEV; |
| 108 | |
Josef Sipek | d4176d3 | 2006-12-08 02:36:56 -0800 | [diff] [blame^] | 109 | coda_inode = coda_file->f_path.dentry->d_inode; |
| 110 | host_inode = host_file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | coda_file->f_mapping = host_file->f_mapping; |
| 112 | if (coda_inode->i_mapping == &coda_inode->i_data) |
| 113 | coda_inode->i_mapping = host_inode->i_mapping; |
| 114 | |
| 115 | /* only allow additional mmaps as long as userspace isn't changing |
| 116 | * the container file on us! */ |
| 117 | else if (coda_inode->i_mapping != host_inode->i_mapping) |
| 118 | return -EBUSY; |
| 119 | |
| 120 | /* keep track of how often the coda_inode/host_file has been mmapped */ |
| 121 | cii = ITOC(coda_inode); |
| 122 | cii->c_mapcount++; |
| 123 | cfi->cfi_mapcount++; |
| 124 | |
| 125 | return host_file->f_op->mmap(host_file, vma); |
| 126 | } |
| 127 | |
| 128 | int coda_open(struct inode *coda_inode, struct file *coda_file) |
| 129 | { |
| 130 | struct file *host_file = NULL; |
| 131 | int error; |
| 132 | unsigned short flags = coda_file->f_flags & (~O_EXCL); |
| 133 | unsigned short coda_flags = coda_flags_to_cflags(flags); |
| 134 | struct coda_file_info *cfi; |
| 135 | |
| 136 | coda_vfs_stat.open++; |
| 137 | |
| 138 | cfi = kmalloc(sizeof(struct coda_file_info), GFP_KERNEL); |
Josh Triplett | 6ecbc4e | 2006-07-30 03:03:56 -0700 | [diff] [blame] | 139 | if (!cfi) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | |
| 142 | lock_kernel(); |
| 143 | |
| 144 | error = venus_open(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags, |
| 145 | &host_file); |
| 146 | if (error || !host_file) { |
| 147 | kfree(cfi); |
| 148 | unlock_kernel(); |
| 149 | return error; |
| 150 | } |
| 151 | |
| 152 | host_file->f_flags |= coda_file->f_flags & (O_APPEND | O_SYNC); |
| 153 | |
| 154 | cfi->cfi_magic = CODA_MAGIC; |
| 155 | cfi->cfi_mapcount = 0; |
| 156 | cfi->cfi_container = host_file; |
| 157 | |
| 158 | BUG_ON(coda_file->private_data != NULL); |
| 159 | coda_file->private_data = cfi; |
| 160 | |
| 161 | unlock_kernel(); |
| 162 | return 0; |
| 163 | } |
| 164 | |
Miklos Szeredi | 75e1fcc | 2006-06-23 02:05:12 -0700 | [diff] [blame] | 165 | int coda_flush(struct file *coda_file, fl_owner_t id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | { |
| 167 | unsigned short flags = coda_file->f_flags & ~O_EXCL; |
| 168 | unsigned short coda_flags = coda_flags_to_cflags(flags); |
| 169 | struct coda_file_info *cfi; |
| 170 | struct inode *coda_inode; |
| 171 | int err = 0, fcnt; |
| 172 | |
| 173 | lock_kernel(); |
| 174 | |
| 175 | coda_vfs_stat.flush++; |
| 176 | |
| 177 | /* last close semantics */ |
| 178 | fcnt = file_count(coda_file); |
| 179 | if (fcnt > 1) |
| 180 | goto out; |
| 181 | |
| 182 | /* No need to make an upcall when we have not made any modifications |
| 183 | * to the file */ |
| 184 | if ((coda_file->f_flags & O_ACCMODE) == O_RDONLY) |
| 185 | goto out; |
| 186 | |
| 187 | if (use_coda_close) |
| 188 | goto out; |
| 189 | |
| 190 | cfi = CODA_FTOC(coda_file); |
| 191 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); |
| 192 | |
Josef Sipek | d4176d3 | 2006-12-08 02:36:56 -0800 | [diff] [blame^] | 193 | coda_inode = coda_file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | |
| 195 | err = venus_store(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags, |
| 196 | coda_file->f_uid); |
| 197 | |
| 198 | if (err == -EOPNOTSUPP) { |
| 199 | use_coda_close = 1; |
| 200 | err = 0; |
| 201 | } |
| 202 | |
| 203 | out: |
| 204 | unlock_kernel(); |
| 205 | return err; |
| 206 | } |
| 207 | |
| 208 | int coda_release(struct inode *coda_inode, struct file *coda_file) |
| 209 | { |
| 210 | unsigned short flags = (coda_file->f_flags) & (~O_EXCL); |
| 211 | unsigned short coda_flags = coda_flags_to_cflags(flags); |
| 212 | struct coda_file_info *cfi; |
| 213 | struct coda_inode_info *cii; |
| 214 | struct inode *host_inode; |
| 215 | int err = 0; |
| 216 | |
| 217 | lock_kernel(); |
| 218 | coda_vfs_stat.release++; |
| 219 | |
| 220 | if (!use_coda_close) { |
| 221 | err = venus_release(coda_inode->i_sb, coda_i2f(coda_inode), |
| 222 | coda_flags); |
| 223 | if (err == -EOPNOTSUPP) { |
| 224 | use_coda_close = 1; |
| 225 | err = 0; |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | cfi = CODA_FTOC(coda_file); |
| 230 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); |
| 231 | |
| 232 | if (use_coda_close) |
| 233 | err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode), |
| 234 | coda_flags, coda_file->f_uid); |
| 235 | |
Josef Sipek | d4176d3 | 2006-12-08 02:36:56 -0800 | [diff] [blame^] | 236 | host_inode = cfi->cfi_container->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | cii = ITOC(coda_inode); |
| 238 | |
| 239 | /* did we mmap this file? */ |
| 240 | if (coda_inode->i_mapping == &host_inode->i_data) { |
| 241 | cii->c_mapcount -= cfi->cfi_mapcount; |
| 242 | if (!cii->c_mapcount) |
| 243 | coda_inode->i_mapping = &coda_inode->i_data; |
| 244 | } |
| 245 | |
| 246 | fput(cfi->cfi_container); |
| 247 | kfree(coda_file->private_data); |
| 248 | coda_file->private_data = NULL; |
| 249 | |
| 250 | unlock_kernel(); |
| 251 | return err; |
| 252 | } |
| 253 | |
| 254 | int coda_fsync(struct file *coda_file, struct dentry *coda_dentry, int datasync) |
| 255 | { |
| 256 | struct file *host_file; |
| 257 | struct dentry *host_dentry; |
| 258 | struct inode *host_inode, *coda_inode = coda_dentry->d_inode; |
| 259 | struct coda_file_info *cfi; |
| 260 | int err = 0; |
| 261 | |
| 262 | if (!(S_ISREG(coda_inode->i_mode) || S_ISDIR(coda_inode->i_mode) || |
| 263 | S_ISLNK(coda_inode->i_mode))) |
| 264 | return -EINVAL; |
| 265 | |
| 266 | cfi = CODA_FTOC(coda_file); |
| 267 | BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); |
| 268 | host_file = cfi->cfi_container; |
| 269 | |
| 270 | coda_vfs_stat.fsync++; |
| 271 | |
| 272 | if (host_file->f_op && host_file->f_op->fsync) { |
Josef Sipek | d4176d3 | 2006-12-08 02:36:56 -0800 | [diff] [blame^] | 273 | host_dentry = host_file->f_path.dentry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | host_inode = host_dentry->d_inode; |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 275 | mutex_lock(&host_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | err = host_file->f_op->fsync(host_file, host_dentry, datasync); |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 277 | mutex_unlock(&host_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | } |
| 279 | |
| 280 | if ( !err && !datasync ) { |
| 281 | lock_kernel(); |
| 282 | err = venus_fsync(coda_inode->i_sb, coda_i2f(coda_inode)); |
| 283 | unlock_kernel(); |
| 284 | } |
| 285 | |
| 286 | return err; |
| 287 | } |
| 288 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 289 | const struct file_operations coda_file_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 290 | .llseek = generic_file_llseek, |
| 291 | .read = coda_file_read, |
| 292 | .write = coda_file_write, |
| 293 | .mmap = coda_file_mmap, |
| 294 | .open = coda_open, |
| 295 | .flush = coda_flush, |
| 296 | .release = coda_release, |
| 297 | .fsync = coda_fsync, |
| 298 | .sendfile = coda_file_sendfile, |
| 299 | }; |
| 300 | |