rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 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); |