1 /* 2 * Copyright (c) 2002 Red Hat, Inc. All rights reserved. 3 * 4 * This software may be freely redistributed under the terms of the 5 * GNU General Public License. 6 * 7 * You should have received a copy of the GNU General Public License 8 * along with this program; if not, write to the Free Software 9 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 10 * 11 * Authors: David Woodhouse <dwmw2@cambridge.redhat.com> 12 * David Howells <dhowells@redhat.com> 13 * 14 */ 15 16 #include <linux/kernel.h> 17 #include <linux/module.h> 18 #include <linux/init.h> 19 #include <linux/slab.h> 20 #include <linux/fs.h> 21 #include <linux/pagemap.h> 22 #include "volume.h" 23 #include "vnode.h" 24 #include "super.h" 25 #include "internal.h" 26 27 struct afs_iget_data { 28 struct afs_fid fid; 29 struct afs_volume *volume; /* volume on which resides */ 30 }; 31 32 /*****************************************************************************/ 33 /* 34 * map the AFS file status to the inode member variables 35 */ 36 static int afs_inode_map_status(struct afs_vnode *vnode) 37 { 38 struct inode *inode = AFS_VNODE_TO_I(vnode); 39 40 _debug("FS: ft=%d lk=%d sz=%Zu ver=%Lu mod=%hu", 41 vnode->status.type, 42 vnode->status.nlink, 43 vnode->status.size, 44 vnode->status.version, 45 vnode->status.mode); 46 47 switch (vnode->status.type) { 48 case AFS_FTYPE_FILE: 49 inode->i_mode = S_IFREG | vnode->status.mode; 50 inode->i_op = &afs_file_inode_operations; 51 inode->i_fop = &generic_ro_fops; 52 break; 53 case AFS_FTYPE_DIR: 54 inode->i_mode = S_IFDIR | vnode->status.mode; 55 inode->i_op = &afs_dir_inode_operations; 56 inode->i_fop = &afs_dir_file_operations; 57 break; 58 case AFS_FTYPE_SYMLINK: 59 inode->i_mode = S_IFLNK | vnode->status.mode; 60 inode->i_op = &page_symlink_inode_operations; 61 break; 62 default: 63 printk("kAFS: AFS vnode with undefined type\n"); 64 return -EBADMSG; 65 } 66 67 inode->i_nlink = vnode->status.nlink; 68 inode->i_uid = vnode->status.owner; 69 inode->i_gid = 0; 70 inode->i_size = vnode->status.size; 71 inode->i_ctime.tv_sec = vnode->status.mtime_server; 72 inode->i_ctime.tv_nsec = 0; 73 inode->i_atime = inode->i_mtime = inode->i_ctime; 74 inode->i_blocks = 0; 75 inode->i_version = vnode->fid.unique; 76 inode->i_mapping->a_ops = &afs_fs_aops; 77 78 /* check to see whether a symbolic link is really a mountpoint */ 79 if (vnode->status.type == AFS_FTYPE_SYMLINK) { 80 afs_mntpt_check_symlink(vnode); 81 82 if (vnode->flags & AFS_VNODE_MOUNTPOINT) { 83 inode->i_mode = S_IFDIR | vnode->status.mode; 84 inode->i_op = &afs_mntpt_inode_operations; 85 inode->i_fop = &afs_mntpt_file_operations; 86 } 87 } 88 89 return 0; 90 } /* end afs_inode_map_status() */ 91 92 /*****************************************************************************/ 93 /* 94 * attempt to fetch the status of an inode, coelescing multiple simultaneous 95 * fetches 96 */ 97 static int afs_inode_fetch_status(struct inode *inode) 98 { 99 struct afs_vnode *vnode; 100 int ret; 101 102 vnode = AFS_FS_I(inode); 103 104 ret = afs_vnode_fetch_status(vnode); 105 106 if (ret == 0) 107 ret = afs_inode_map_status(vnode); 108 109 return ret; 110 111 } /* end afs_inode_fetch_status() */ 112 113 /*****************************************************************************/ 114 /* 115 * iget5() comparator 116 */ 117 static int afs_iget5_test(struct inode *inode, void *opaque) 118 { 119 struct afs_iget_data *data = opaque; 120 121 return inode->i_ino == data->fid.vnode && 122 inode->i_version == data->fid.unique; 123 } /* end afs_iget5_test() */ 124 125 /*****************************************************************************/ 126 /* 127 * iget5() inode initialiser 128 */ 129 static int afs_iget5_set(struct inode *inode, void *opaque) 130 { 131 struct afs_iget_data *data = opaque; 132 struct afs_vnode *vnode = AFS_FS_I(inode); 133 134 inode->i_ino = data->fid.vnode; 135 inode->i_version = data->fid.unique; 136 vnode->fid = data->fid; 137 vnode->volume = data->volume; 138 139 return 0; 140 } /* end afs_iget5_set() */ 141 142 /*****************************************************************************/ 143 /* 144 * inode retrieval 145 */ 146 inline int afs_iget(struct super_block *sb, struct afs_fid *fid, 147 struct inode **_inode) 148 { 149 struct afs_iget_data data = { .fid = *fid }; 150 struct afs_super_info *as; 151 struct afs_vnode *vnode; 152 struct inode *inode; 153 int ret; 154 155 _enter(",{%u,%u,%u},,", fid->vid, fid->vnode, fid->unique); 156 157 as = sb->s_fs_info; 158 data.volume = as->volume; 159 160 inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set, 161 &data); 162 if (!inode) { 163 _leave(" = -ENOMEM"); 164 return -ENOMEM; 165 } 166 167 vnode = AFS_FS_I(inode); 168 169 /* deal with an existing inode */ 170 if (!(inode->i_state & I_NEW)) { 171 ret = afs_vnode_fetch_status(vnode); 172 if (ret==0) 173 *_inode = inode; 174 else 175 iput(inode); 176 _leave(" = %d", ret); 177 return ret; 178 } 179 180 #ifdef AFS_CACHING_SUPPORT 181 /* set up caching before reading the status, as fetch-status reads the 182 * first page of symlinks to see if they're really mntpts */ 183 cachefs_acquire_cookie(vnode->volume->cache, 184 NULL, 185 vnode, 186 &vnode->cache); 187 #endif 188 189 /* okay... it's a new inode */ 190 inode->i_flags |= S_NOATIME; 191 vnode->flags |= AFS_VNODE_CHANGED; 192 ret = afs_inode_fetch_status(inode); 193 if (ret<0) 194 goto bad_inode; 195 196 /* success */ 197 unlock_new_inode(inode); 198 199 *_inode = inode; 200 _leave(" = 0 [CB { v=%u x=%lu t=%u }]", 201 vnode->cb_version, 202 vnode->cb_timeout.timo_jif, 203 vnode->cb_type); 204 return 0; 205 206 /* failure */ 207 bad_inode: 208 make_bad_inode(inode); 209 unlock_new_inode(inode); 210 iput(inode); 211 212 _leave(" = %d [bad]", ret); 213 return ret; 214 } /* end afs_iget() */ 215 216 /*****************************************************************************/ 217 /* 218 * read the attributes of an inode 219 */ 220 int afs_inode_getattr(struct vfsmount *mnt, struct dentry *dentry, 221 struct kstat *stat) 222 { 223 struct afs_vnode *vnode; 224 struct inode *inode; 225 int ret; 226 227 inode = dentry->d_inode; 228 229 _enter("{ ino=%lu v=%lu }", inode->i_ino, inode->i_version); 230 231 vnode = AFS_FS_I(inode); 232 233 ret = afs_inode_fetch_status(inode); 234 if (ret == -ENOENT) { 235 _leave(" = %d [%d %p]", 236 ret, atomic_read(&dentry->d_count), dentry->d_inode); 237 return ret; 238 } 239 else if (ret < 0) { 240 make_bad_inode(inode); 241 _leave(" = %d", ret); 242 return ret; 243 } 244 245 /* transfer attributes from the inode structure to the stat 246 * structure */ 247 generic_fillattr(inode, stat); 248 249 _leave(" = 0 CB { v=%u x=%u t=%u }", 250 vnode->cb_version, 251 vnode->cb_expiry, 252 vnode->cb_type); 253 254 return 0; 255 } /* end afs_inode_getattr() */ 256 257 /*****************************************************************************/ 258 /* 259 * clear an AFS inode 260 */ 261 void afs_clear_inode(struct inode *inode) 262 { 263 struct afs_vnode *vnode; 264 265 vnode = AFS_FS_I(inode); 266 267 _enter("ino=%lu { vn=%08x v=%u x=%u t=%u }", 268 inode->i_ino, 269 vnode->fid.vnode, 270 vnode->cb_version, 271 vnode->cb_expiry, 272 vnode->cb_type 273 ); 274 275 BUG_ON(inode->i_ino != vnode->fid.vnode); 276 277 afs_vnode_give_up_callback(vnode); 278 279 #ifdef AFS_CACHING_SUPPORT 280 cachefs_relinquish_cookie(vnode->cache, 0); 281 vnode->cache = NULL; 282 #endif 283 284 _leave(""); 285 } /* end afs_clear_inode() */ 286