1 /* 2 * Copyright (c) 2000-2001 Christoph Hellwig. 3 * Copyright (c) 2016 Krzysztof Blaszkowski 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions, and the following disclaimer, 11 * without modification. 12 * 2. The name of the author may not be used to endorse or promote products 13 * derived from this software without specific prior written permission. 14 * 15 * Alternatively, this software may be distributed under the terms of the 16 * GNU General Public License ("GPL"). 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 22 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 /* 32 * Veritas filesystem driver - superblock related routines. 33 */ 34 #include <linux/init.h> 35 #include <linux/module.h> 36 37 #include <linux/blkdev.h> 38 #include <linux/fs.h> 39 #include <linux/buffer_head.h> 40 #include <linux/kernel.h> 41 #include <linux/slab.h> 42 #include <linux/stat.h> 43 #include <linux/vfs.h> 44 #include <linux/mount.h> 45 46 #include "vxfs.h" 47 #include "vxfs_extern.h" 48 #include "vxfs_dir.h" 49 #include "vxfs_inode.h" 50 51 52 MODULE_AUTHOR("Christoph Hellwig, Krzysztof Blaszkowski"); 53 MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver"); 54 MODULE_LICENSE("Dual BSD/GPL"); 55 56 static struct kmem_cache *vxfs_inode_cachep; 57 58 /** 59 * vxfs_put_super - free superblock resources 60 * @sbp: VFS superblock. 61 * 62 * Description: 63 * vxfs_put_super frees all resources allocated for @sbp 64 * after the last instance of the filesystem is unmounted. 65 */ 66 67 static void 68 vxfs_put_super(struct super_block *sbp) 69 { 70 struct vxfs_sb_info *infp = VXFS_SBI(sbp); 71 72 iput(infp->vsi_fship); 73 iput(infp->vsi_ilist); 74 iput(infp->vsi_stilist); 75 76 brelse(infp->vsi_bp); 77 kfree(infp); 78 } 79 80 /** 81 * vxfs_statfs - get filesystem information 82 * @dentry: VFS dentry to locate superblock 83 * @bufp: output buffer 84 * 85 * Description: 86 * vxfs_statfs fills the statfs buffer @bufp with information 87 * about the filesystem described by @dentry. 88 * 89 * Returns: 90 * Zero. 91 * 92 * Locking: 93 * No locks held. 94 * 95 * Notes: 96 * This is everything but complete... 97 */ 98 static int 99 vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp) 100 { 101 struct vxfs_sb_info *infp = VXFS_SBI(dentry->d_sb); 102 struct vxfs_sb *raw_sb = infp->vsi_raw; 103 104 bufp->f_type = VXFS_SUPER_MAGIC; 105 bufp->f_bsize = dentry->d_sb->s_blocksize; 106 bufp->f_blocks = fs32_to_cpu(infp, raw_sb->vs_dsize); 107 bufp->f_bfree = fs32_to_cpu(infp, raw_sb->vs_free); 108 bufp->f_bavail = 0; 109 bufp->f_files = 0; 110 bufp->f_ffree = fs32_to_cpu(infp, raw_sb->vs_ifree); 111 bufp->f_namelen = VXFS_NAMELEN; 112 113 return 0; 114 } 115 116 static int vxfs_remount(struct super_block *sb, int *flags, char *data) 117 { 118 sync_filesystem(sb); 119 *flags |= MS_RDONLY; 120 return 0; 121 } 122 123 static struct inode *vxfs_alloc_inode(struct super_block *sb) 124 { 125 struct vxfs_inode_info *vi; 126 127 vi = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL); 128 if (!vi) 129 return NULL; 130 inode_init_once(&vi->vfs_inode); 131 return &vi->vfs_inode; 132 } 133 134 static void vxfs_i_callback(struct rcu_head *head) 135 { 136 struct inode *inode = container_of(head, struct inode, i_rcu); 137 138 kmem_cache_free(vxfs_inode_cachep, VXFS_INO(inode)); 139 } 140 141 static void vxfs_destroy_inode(struct inode *inode) 142 { 143 call_rcu(&inode->i_rcu, vxfs_i_callback); 144 } 145 146 static const struct super_operations vxfs_super_ops = { 147 .alloc_inode = vxfs_alloc_inode, 148 .destroy_inode = vxfs_destroy_inode, 149 .evict_inode = vxfs_evict_inode, 150 .put_super = vxfs_put_super, 151 .statfs = vxfs_statfs, 152 .remount_fs = vxfs_remount, 153 }; 154 155 static int vxfs_try_sb_magic(struct super_block *sbp, int silent, 156 unsigned blk, __fs32 magic) 157 { 158 struct buffer_head *bp; 159 struct vxfs_sb *rsbp; 160 struct vxfs_sb_info *infp = VXFS_SBI(sbp); 161 int rc = -ENOMEM; 162 163 bp = sb_bread(sbp, blk); 164 do { 165 if (!bp || !buffer_mapped(bp)) { 166 if (!silent) { 167 printk(KERN_WARNING 168 "vxfs: unable to read disk superblock at %u\n", 169 blk); 170 } 171 break; 172 } 173 174 rc = -EINVAL; 175 rsbp = (struct vxfs_sb *)bp->b_data; 176 if (rsbp->vs_magic != magic) { 177 if (!silent) 178 printk(KERN_NOTICE 179 "vxfs: WRONG superblock magic %08x at %u\n", 180 rsbp->vs_magic, blk); 181 break; 182 } 183 184 rc = 0; 185 infp->vsi_raw = rsbp; 186 infp->vsi_bp = bp; 187 } while (0); 188 189 if (rc) { 190 infp->vsi_raw = NULL; 191 infp->vsi_bp = NULL; 192 brelse(bp); 193 } 194 195 return rc; 196 } 197 198 /** 199 * vxfs_read_super - read superblock into memory and initialize filesystem 200 * @sbp: VFS superblock (to fill) 201 * @dp: fs private mount data 202 * @silent: do not complain loudly when sth is wrong 203 * 204 * Description: 205 * We are called on the first mount of a filesystem to read the 206 * superblock into memory and do some basic setup. 207 * 208 * Returns: 209 * The superblock on success, else %NULL. 210 * 211 * Locking: 212 * We are under @sbp->s_lock. 213 */ 214 static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent) 215 { 216 struct vxfs_sb_info *infp; 217 struct vxfs_sb *rsbp; 218 u_long bsize; 219 struct inode *root; 220 int ret = -EINVAL; 221 u32 j; 222 223 sbp->s_flags |= MS_RDONLY; 224 225 infp = kzalloc(sizeof(*infp), GFP_KERNEL); 226 if (!infp) { 227 printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n"); 228 return -ENOMEM; 229 } 230 231 bsize = sb_min_blocksize(sbp, BLOCK_SIZE); 232 if (!bsize) { 233 printk(KERN_WARNING "vxfs: unable to set blocksize\n"); 234 goto out; 235 } 236 237 sbp->s_op = &vxfs_super_ops; 238 sbp->s_fs_info = infp; 239 240 if (!vxfs_try_sb_magic(sbp, silent, 1, 241 (__force __fs32)cpu_to_le32(VXFS_SUPER_MAGIC))) { 242 /* Unixware, x86 */ 243 infp->byte_order = VXFS_BO_LE; 244 } else if (!vxfs_try_sb_magic(sbp, silent, 8, 245 (__force __fs32)cpu_to_be32(VXFS_SUPER_MAGIC))) { 246 /* HP-UX, parisc */ 247 infp->byte_order = VXFS_BO_BE; 248 } else { 249 if (!silent) 250 printk(KERN_NOTICE "vxfs: can't find superblock.\n"); 251 goto out; 252 } 253 254 rsbp = infp->vsi_raw; 255 j = fs32_to_cpu(infp, rsbp->vs_version); 256 if ((j < 2 || j > 4) && !silent) { 257 printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n", j); 258 goto out; 259 } 260 261 #ifdef DIAGNOSTIC 262 printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", j); 263 printk(KERN_DEBUG "vxfs: blocksize: %d\n", 264 fs32_to_cpu(infp, rsbp->vs_bsize)); 265 #endif 266 267 sbp->s_magic = fs32_to_cpu(infp, rsbp->vs_magic); 268 269 infp->vsi_oltext = fs32_to_cpu(infp, rsbp->vs_oltext[0]); 270 infp->vsi_oltsize = fs32_to_cpu(infp, rsbp->vs_oltsize); 271 272 j = fs32_to_cpu(infp, rsbp->vs_bsize); 273 if (!sb_set_blocksize(sbp, j)) { 274 printk(KERN_WARNING "vxfs: unable to set final block size\n"); 275 goto out; 276 } 277 278 if (vxfs_read_olt(sbp, bsize)) { 279 printk(KERN_WARNING "vxfs: unable to read olt\n"); 280 goto out; 281 } 282 283 if (vxfs_read_fshead(sbp)) { 284 printk(KERN_WARNING "vxfs: unable to read fshead\n"); 285 goto out; 286 } 287 288 root = vxfs_iget(sbp, VXFS_ROOT_INO); 289 if (IS_ERR(root)) { 290 ret = PTR_ERR(root); 291 goto out; 292 } 293 sbp->s_root = d_make_root(root); 294 if (!sbp->s_root) { 295 printk(KERN_WARNING "vxfs: unable to get root dentry.\n"); 296 goto out_free_ilist; 297 } 298 299 return 0; 300 301 out_free_ilist: 302 iput(infp->vsi_fship); 303 iput(infp->vsi_ilist); 304 iput(infp->vsi_stilist); 305 out: 306 brelse(infp->vsi_bp); 307 kfree(infp); 308 return ret; 309 } 310 311 /* 312 * The usual module blurb. 313 */ 314 static struct dentry *vxfs_mount(struct file_system_type *fs_type, 315 int flags, const char *dev_name, void *data) 316 { 317 return mount_bdev(fs_type, flags, dev_name, data, vxfs_fill_super); 318 } 319 320 static struct file_system_type vxfs_fs_type = { 321 .owner = THIS_MODULE, 322 .name = "vxfs", 323 .mount = vxfs_mount, 324 .kill_sb = kill_block_super, 325 .fs_flags = FS_REQUIRES_DEV, 326 }; 327 MODULE_ALIAS_FS("vxfs"); /* makes mount -t vxfs autoload the module */ 328 MODULE_ALIAS("vxfs"); 329 330 static int __init 331 vxfs_init(void) 332 { 333 int rv; 334 335 vxfs_inode_cachep = kmem_cache_create("vxfs_inode", 336 sizeof(struct vxfs_inode_info), 0, 337 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL); 338 if (!vxfs_inode_cachep) 339 return -ENOMEM; 340 rv = register_filesystem(&vxfs_fs_type); 341 if (rv < 0) 342 kmem_cache_destroy(vxfs_inode_cachep); 343 return rv; 344 } 345 346 static void __exit 347 vxfs_cleanup(void) 348 { 349 unregister_filesystem(&vxfs_fs_type); 350 /* 351 * Make sure all delayed rcu free inodes are flushed before we 352 * destroy cache. 353 */ 354 rcu_barrier(); 355 kmem_cache_destroy(vxfs_inode_cachep); 356 } 357 358 module_init(vxfs_init); 359 module_exit(vxfs_cleanup); 360