1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2000-2001 Christoph Hellwig. 4 * Copyright (c) 2016 Krzysztof Blaszkowski 5 */ 6 7 /* 8 * Veritas filesystem driver - superblock related routines. 9 */ 10 #include <linux/init.h> 11 #include <linux/module.h> 12 13 #include <linux/blkdev.h> 14 #include <linux/fs.h> 15 #include <linux/buffer_head.h> 16 #include <linux/kernel.h> 17 #include <linux/slab.h> 18 #include <linux/stat.h> 19 #include <linux/vfs.h> 20 #include <linux/mount.h> 21 22 #include "vxfs.h" 23 #include "vxfs_extern.h" 24 #include "vxfs_dir.h" 25 #include "vxfs_inode.h" 26 27 28 MODULE_AUTHOR("Christoph Hellwig, Krzysztof Blaszkowski"); 29 MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver"); 30 MODULE_LICENSE("Dual BSD/GPL"); 31 32 static struct kmem_cache *vxfs_inode_cachep; 33 34 /** 35 * vxfs_put_super - free superblock resources 36 * @sbp: VFS superblock. 37 * 38 * Description: 39 * vxfs_put_super frees all resources allocated for @sbp 40 * after the last instance of the filesystem is unmounted. 41 */ 42 43 static void 44 vxfs_put_super(struct super_block *sbp) 45 { 46 struct vxfs_sb_info *infp = VXFS_SBI(sbp); 47 48 iput(infp->vsi_fship); 49 iput(infp->vsi_ilist); 50 iput(infp->vsi_stilist); 51 52 brelse(infp->vsi_bp); 53 kfree(infp); 54 } 55 56 /** 57 * vxfs_statfs - get filesystem information 58 * @dentry: VFS dentry to locate superblock 59 * @bufp: output buffer 60 * 61 * Description: 62 * vxfs_statfs fills the statfs buffer @bufp with information 63 * about the filesystem described by @dentry. 64 * 65 * Returns: 66 * Zero. 67 * 68 * Locking: 69 * No locks held. 70 * 71 * Notes: 72 * This is everything but complete... 73 */ 74 static int 75 vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp) 76 { 77 struct vxfs_sb_info *infp = VXFS_SBI(dentry->d_sb); 78 struct vxfs_sb *raw_sb = infp->vsi_raw; 79 80 bufp->f_type = VXFS_SUPER_MAGIC; 81 bufp->f_bsize = dentry->d_sb->s_blocksize; 82 bufp->f_blocks = fs32_to_cpu(infp, raw_sb->vs_dsize); 83 bufp->f_bfree = fs32_to_cpu(infp, raw_sb->vs_free); 84 bufp->f_bavail = 0; 85 bufp->f_files = 0; 86 bufp->f_ffree = fs32_to_cpu(infp, raw_sb->vs_ifree); 87 bufp->f_namelen = VXFS_NAMELEN; 88 89 return 0; 90 } 91 92 static int vxfs_remount(struct super_block *sb, int *flags, char *data) 93 { 94 sync_filesystem(sb); 95 *flags |= SB_RDONLY; 96 return 0; 97 } 98 99 static struct inode *vxfs_alloc_inode(struct super_block *sb) 100 { 101 struct vxfs_inode_info *vi; 102 103 vi = alloc_inode_sb(sb, vxfs_inode_cachep, GFP_KERNEL); 104 if (!vi) 105 return NULL; 106 inode_init_once(&vi->vfs_inode); 107 return &vi->vfs_inode; 108 } 109 110 static void vxfs_free_inode(struct inode *inode) 111 { 112 kmem_cache_free(vxfs_inode_cachep, VXFS_INO(inode)); 113 } 114 115 static const struct super_operations vxfs_super_ops = { 116 .alloc_inode = vxfs_alloc_inode, 117 .free_inode = vxfs_free_inode, 118 .evict_inode = vxfs_evict_inode, 119 .put_super = vxfs_put_super, 120 .statfs = vxfs_statfs, 121 .remount_fs = vxfs_remount, 122 }; 123 124 static int vxfs_try_sb_magic(struct super_block *sbp, int silent, 125 unsigned blk, __fs32 magic) 126 { 127 struct buffer_head *bp; 128 struct vxfs_sb *rsbp; 129 struct vxfs_sb_info *infp = VXFS_SBI(sbp); 130 int rc = -ENOMEM; 131 132 bp = sb_bread(sbp, blk); 133 do { 134 if (!bp || !buffer_mapped(bp)) { 135 if (!silent) { 136 printk(KERN_WARNING 137 "vxfs: unable to read disk superblock at %u\n", 138 blk); 139 } 140 break; 141 } 142 143 rc = -EINVAL; 144 rsbp = (struct vxfs_sb *)bp->b_data; 145 if (rsbp->vs_magic != magic) { 146 if (!silent) 147 printk(KERN_NOTICE 148 "vxfs: WRONG superblock magic %08x at %u\n", 149 rsbp->vs_magic, blk); 150 break; 151 } 152 153 rc = 0; 154 infp->vsi_raw = rsbp; 155 infp->vsi_bp = bp; 156 } while (0); 157 158 if (rc) { 159 infp->vsi_raw = NULL; 160 infp->vsi_bp = NULL; 161 brelse(bp); 162 } 163 164 return rc; 165 } 166 167 /** 168 * vxfs_fill_super - read superblock into memory and initialize filesystem 169 * @sbp: VFS superblock (to fill) 170 * @dp: fs private mount data 171 * @silent: do not complain loudly when sth is wrong 172 * 173 * Description: 174 * We are called on the first mount of a filesystem to read the 175 * superblock into memory and do some basic setup. 176 * 177 * Returns: 178 * The superblock on success, else %NULL. 179 * 180 * Locking: 181 * We are under @sbp->s_lock. 182 */ 183 static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent) 184 { 185 struct vxfs_sb_info *infp; 186 struct vxfs_sb *rsbp; 187 u_long bsize; 188 struct inode *root; 189 int ret = -EINVAL; 190 u32 j; 191 192 sbp->s_flags |= SB_RDONLY; 193 194 infp = kzalloc(sizeof(*infp), GFP_KERNEL); 195 if (!infp) { 196 printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n"); 197 return -ENOMEM; 198 } 199 200 bsize = sb_min_blocksize(sbp, BLOCK_SIZE); 201 if (!bsize) { 202 printk(KERN_WARNING "vxfs: unable to set blocksize\n"); 203 goto out; 204 } 205 206 sbp->s_op = &vxfs_super_ops; 207 sbp->s_fs_info = infp; 208 sbp->s_time_min = 0; 209 sbp->s_time_max = U32_MAX; 210 211 if (!vxfs_try_sb_magic(sbp, silent, 1, 212 (__force __fs32)cpu_to_le32(VXFS_SUPER_MAGIC))) { 213 /* Unixware, x86 */ 214 infp->byte_order = VXFS_BO_LE; 215 } else if (!vxfs_try_sb_magic(sbp, silent, 8, 216 (__force __fs32)cpu_to_be32(VXFS_SUPER_MAGIC))) { 217 /* HP-UX, parisc */ 218 infp->byte_order = VXFS_BO_BE; 219 } else { 220 if (!silent) 221 printk(KERN_NOTICE "vxfs: can't find superblock.\n"); 222 goto out; 223 } 224 225 rsbp = infp->vsi_raw; 226 j = fs32_to_cpu(infp, rsbp->vs_version); 227 if ((j < 2 || j > 4) && !silent) { 228 printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n", j); 229 goto out; 230 } 231 232 #ifdef DIAGNOSTIC 233 printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", j); 234 printk(KERN_DEBUG "vxfs: blocksize: %d\n", 235 fs32_to_cpu(infp, rsbp->vs_bsize)); 236 #endif 237 238 sbp->s_magic = fs32_to_cpu(infp, rsbp->vs_magic); 239 240 infp->vsi_oltext = fs32_to_cpu(infp, rsbp->vs_oltext[0]); 241 infp->vsi_oltsize = fs32_to_cpu(infp, rsbp->vs_oltsize); 242 243 j = fs32_to_cpu(infp, rsbp->vs_bsize); 244 if (!sb_set_blocksize(sbp, j)) { 245 printk(KERN_WARNING "vxfs: unable to set final block size\n"); 246 goto out; 247 } 248 249 if (vxfs_read_olt(sbp, bsize)) { 250 printk(KERN_WARNING "vxfs: unable to read olt\n"); 251 goto out; 252 } 253 254 if (vxfs_read_fshead(sbp)) { 255 printk(KERN_WARNING "vxfs: unable to read fshead\n"); 256 goto out; 257 } 258 259 root = vxfs_iget(sbp, VXFS_ROOT_INO); 260 if (IS_ERR(root)) { 261 ret = PTR_ERR(root); 262 goto out; 263 } 264 sbp->s_root = d_make_root(root); 265 if (!sbp->s_root) { 266 printk(KERN_WARNING "vxfs: unable to get root dentry.\n"); 267 goto out_free_ilist; 268 } 269 270 return 0; 271 272 out_free_ilist: 273 iput(infp->vsi_fship); 274 iput(infp->vsi_ilist); 275 iput(infp->vsi_stilist); 276 out: 277 brelse(infp->vsi_bp); 278 kfree(infp); 279 return ret; 280 } 281 282 /* 283 * The usual module blurb. 284 */ 285 static struct dentry *vxfs_mount(struct file_system_type *fs_type, 286 int flags, const char *dev_name, void *data) 287 { 288 return mount_bdev(fs_type, flags, dev_name, data, vxfs_fill_super); 289 } 290 291 static struct file_system_type vxfs_fs_type = { 292 .owner = THIS_MODULE, 293 .name = "vxfs", 294 .mount = vxfs_mount, 295 .kill_sb = kill_block_super, 296 .fs_flags = FS_REQUIRES_DEV, 297 }; 298 MODULE_ALIAS_FS("vxfs"); /* makes mount -t vxfs autoload the module */ 299 MODULE_ALIAS("vxfs"); 300 301 static int __init 302 vxfs_init(void) 303 { 304 int rv; 305 306 vxfs_inode_cachep = kmem_cache_create_usercopy("vxfs_inode", 307 sizeof(struct vxfs_inode_info), 0, 308 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, 309 offsetof(struct vxfs_inode_info, vii_immed.vi_immed), 310 sizeof_field(struct vxfs_inode_info, 311 vii_immed.vi_immed), 312 NULL); 313 if (!vxfs_inode_cachep) 314 return -ENOMEM; 315 rv = register_filesystem(&vxfs_fs_type); 316 if (rv < 0) 317 kmem_cache_destroy(vxfs_inode_cachep); 318 return rv; 319 } 320 321 static void __exit 322 vxfs_cleanup(void) 323 { 324 unregister_filesystem(&vxfs_fs_type); 325 /* 326 * Make sure all delayed rcu free inodes are flushed before we 327 * destroy cache. 328 */ 329 rcu_barrier(); 330 kmem_cache_destroy(vxfs_inode_cachep); 331 } 332 333 module_init(vxfs_init); 334 module_exit(vxfs_cleanup); 335