1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2017-2018 HUAWEI, Inc. 4 * https://www.huawei.com/ 5 */ 6 #include "xattr.h" 7 8 #include <trace/events/erofs.h> 9 10 /* 11 * if inode is successfully read, return its inode page (or sometimes 12 * the inode payload page if it's an extended inode) in order to fill 13 * inline data if possible. 14 */ 15 static struct page *erofs_read_inode(struct inode *inode, 16 unsigned int *ofs) 17 { 18 struct super_block *sb = inode->i_sb; 19 struct erofs_sb_info *sbi = EROFS_SB(sb); 20 struct erofs_inode *vi = EROFS_I(inode); 21 const erofs_off_t inode_loc = iloc(sbi, vi->nid); 22 23 erofs_blk_t blkaddr, nblks = 0; 24 struct page *page; 25 struct erofs_inode_compact *dic; 26 struct erofs_inode_extended *die, *copied = NULL; 27 unsigned int ifmt; 28 int err; 29 30 blkaddr = erofs_blknr(inode_loc); 31 *ofs = erofs_blkoff(inode_loc); 32 33 erofs_dbg("%s, reading inode nid %llu at %u of blkaddr %u", 34 __func__, vi->nid, *ofs, blkaddr); 35 36 page = erofs_get_meta_page(sb, blkaddr); 37 if (IS_ERR(page)) { 38 erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld", 39 vi->nid, PTR_ERR(page)); 40 return page; 41 } 42 43 dic = page_address(page) + *ofs; 44 ifmt = le16_to_cpu(dic->i_format); 45 46 if (ifmt & ~EROFS_I_ALL) { 47 erofs_err(inode->i_sb, "unsupported i_format %u of nid %llu", 48 ifmt, vi->nid); 49 err = -EOPNOTSUPP; 50 goto err_out; 51 } 52 53 vi->datalayout = erofs_inode_datalayout(ifmt); 54 if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) { 55 erofs_err(inode->i_sb, "unsupported datalayout %u of nid %llu", 56 vi->datalayout, vi->nid); 57 err = -EOPNOTSUPP; 58 goto err_out; 59 } 60 61 switch (erofs_inode_version(ifmt)) { 62 case EROFS_INODE_LAYOUT_EXTENDED: 63 vi->inode_isize = sizeof(struct erofs_inode_extended); 64 /* check if the inode acrosses page boundary */ 65 if (*ofs + vi->inode_isize <= PAGE_SIZE) { 66 *ofs += vi->inode_isize; 67 die = (struct erofs_inode_extended *)dic; 68 } else { 69 const unsigned int gotten = PAGE_SIZE - *ofs; 70 71 copied = kmalloc(vi->inode_isize, GFP_NOFS); 72 if (!copied) { 73 err = -ENOMEM; 74 goto err_out; 75 } 76 memcpy(copied, dic, gotten); 77 unlock_page(page); 78 put_page(page); 79 80 page = erofs_get_meta_page(sb, blkaddr + 1); 81 if (IS_ERR(page)) { 82 erofs_err(sb, "failed to get inode payload page (nid: %llu), err %ld", 83 vi->nid, PTR_ERR(page)); 84 kfree(copied); 85 return page; 86 } 87 *ofs = vi->inode_isize - gotten; 88 memcpy((u8 *)copied + gotten, page_address(page), *ofs); 89 die = copied; 90 } 91 vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount); 92 93 inode->i_mode = le16_to_cpu(die->i_mode); 94 switch (inode->i_mode & S_IFMT) { 95 case S_IFREG: 96 case S_IFDIR: 97 case S_IFLNK: 98 vi->raw_blkaddr = le32_to_cpu(die->i_u.raw_blkaddr); 99 break; 100 case S_IFCHR: 101 case S_IFBLK: 102 inode->i_rdev = 103 new_decode_dev(le32_to_cpu(die->i_u.rdev)); 104 break; 105 case S_IFIFO: 106 case S_IFSOCK: 107 inode->i_rdev = 0; 108 break; 109 default: 110 goto bogusimode; 111 } 112 i_uid_write(inode, le32_to_cpu(die->i_uid)); 113 i_gid_write(inode, le32_to_cpu(die->i_gid)); 114 set_nlink(inode, le32_to_cpu(die->i_nlink)); 115 116 /* extended inode has its own timestamp */ 117 inode->i_ctime.tv_sec = le64_to_cpu(die->i_ctime); 118 inode->i_ctime.tv_nsec = le32_to_cpu(die->i_ctime_nsec); 119 120 inode->i_size = le64_to_cpu(die->i_size); 121 122 /* total blocks for compressed files */ 123 if (erofs_inode_is_data_compressed(vi->datalayout)) 124 nblks = le32_to_cpu(die->i_u.compressed_blocks); 125 126 kfree(copied); 127 break; 128 case EROFS_INODE_LAYOUT_COMPACT: 129 vi->inode_isize = sizeof(struct erofs_inode_compact); 130 *ofs += vi->inode_isize; 131 vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount); 132 133 inode->i_mode = le16_to_cpu(dic->i_mode); 134 switch (inode->i_mode & S_IFMT) { 135 case S_IFREG: 136 case S_IFDIR: 137 case S_IFLNK: 138 vi->raw_blkaddr = le32_to_cpu(dic->i_u.raw_blkaddr); 139 break; 140 case S_IFCHR: 141 case S_IFBLK: 142 inode->i_rdev = 143 new_decode_dev(le32_to_cpu(dic->i_u.rdev)); 144 break; 145 case S_IFIFO: 146 case S_IFSOCK: 147 inode->i_rdev = 0; 148 break; 149 default: 150 goto bogusimode; 151 } 152 i_uid_write(inode, le16_to_cpu(dic->i_uid)); 153 i_gid_write(inode, le16_to_cpu(dic->i_gid)); 154 set_nlink(inode, le16_to_cpu(dic->i_nlink)); 155 156 /* use build time for compact inodes */ 157 inode->i_ctime.tv_sec = sbi->build_time; 158 inode->i_ctime.tv_nsec = sbi->build_time_nsec; 159 160 inode->i_size = le32_to_cpu(dic->i_size); 161 if (erofs_inode_is_data_compressed(vi->datalayout)) 162 nblks = le32_to_cpu(dic->i_u.compressed_blocks); 163 break; 164 default: 165 erofs_err(inode->i_sb, 166 "unsupported on-disk inode version %u of nid %llu", 167 erofs_inode_version(ifmt), vi->nid); 168 err = -EOPNOTSUPP; 169 goto err_out; 170 } 171 172 inode->i_mtime.tv_sec = inode->i_ctime.tv_sec; 173 inode->i_atime.tv_sec = inode->i_ctime.tv_sec; 174 inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec; 175 inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec; 176 177 if (!nblks) 178 /* measure inode.i_blocks as generic filesystems */ 179 inode->i_blocks = roundup(inode->i_size, EROFS_BLKSIZ) >> 9; 180 else 181 inode->i_blocks = nblks << LOG_SECTORS_PER_BLOCK; 182 return page; 183 184 bogusimode: 185 erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu", 186 inode->i_mode, vi->nid); 187 err = -EFSCORRUPTED; 188 err_out: 189 DBG_BUGON(1); 190 kfree(copied); 191 unlock_page(page); 192 put_page(page); 193 return ERR_PTR(err); 194 } 195 196 static int erofs_fill_symlink(struct inode *inode, void *data, 197 unsigned int m_pofs) 198 { 199 struct erofs_inode *vi = EROFS_I(inode); 200 char *lnk; 201 202 /* if it cannot be handled with fast symlink scheme */ 203 if (vi->datalayout != EROFS_INODE_FLAT_INLINE || 204 inode->i_size >= PAGE_SIZE) { 205 inode->i_op = &erofs_symlink_iops; 206 return 0; 207 } 208 209 lnk = kmalloc(inode->i_size + 1, GFP_KERNEL); 210 if (!lnk) 211 return -ENOMEM; 212 213 m_pofs += vi->xattr_isize; 214 /* inline symlink data shouldn't cross page boundary as well */ 215 if (m_pofs + inode->i_size > PAGE_SIZE) { 216 kfree(lnk); 217 erofs_err(inode->i_sb, 218 "inline data cross block boundary @ nid %llu", 219 vi->nid); 220 DBG_BUGON(1); 221 return -EFSCORRUPTED; 222 } 223 224 memcpy(lnk, data + m_pofs, inode->i_size); 225 lnk[inode->i_size] = '\0'; 226 227 inode->i_link = lnk; 228 inode->i_op = &erofs_fast_symlink_iops; 229 return 0; 230 } 231 232 static int erofs_fill_inode(struct inode *inode, int isdir) 233 { 234 struct erofs_inode *vi = EROFS_I(inode); 235 struct page *page; 236 unsigned int ofs; 237 int err = 0; 238 239 trace_erofs_fill_inode(inode, isdir); 240 241 /* read inode base data from disk */ 242 page = erofs_read_inode(inode, &ofs); 243 if (IS_ERR(page)) 244 return PTR_ERR(page); 245 246 /* setup the new inode */ 247 switch (inode->i_mode & S_IFMT) { 248 case S_IFREG: 249 inode->i_op = &erofs_generic_iops; 250 inode->i_fop = &generic_ro_fops; 251 break; 252 case S_IFDIR: 253 inode->i_op = &erofs_dir_iops; 254 inode->i_fop = &erofs_dir_fops; 255 break; 256 case S_IFLNK: 257 err = erofs_fill_symlink(inode, page_address(page), ofs); 258 if (err) 259 goto out_unlock; 260 inode_nohighmem(inode); 261 break; 262 case S_IFCHR: 263 case S_IFBLK: 264 case S_IFIFO: 265 case S_IFSOCK: 266 inode->i_op = &erofs_generic_iops; 267 init_special_inode(inode, inode->i_mode, inode->i_rdev); 268 goto out_unlock; 269 default: 270 err = -EFSCORRUPTED; 271 goto out_unlock; 272 } 273 274 if (erofs_inode_is_data_compressed(vi->datalayout)) { 275 err = z_erofs_fill_inode(inode); 276 goto out_unlock; 277 } 278 inode->i_mapping->a_ops = &erofs_raw_access_aops; 279 280 out_unlock: 281 unlock_page(page); 282 put_page(page); 283 return err; 284 } 285 286 /* 287 * erofs nid is 64bits, but i_ino is 'unsigned long', therefore 288 * we should do more for 32-bit platform to find the right inode. 289 */ 290 static int erofs_ilookup_test_actor(struct inode *inode, void *opaque) 291 { 292 const erofs_nid_t nid = *(erofs_nid_t *)opaque; 293 294 return EROFS_I(inode)->nid == nid; 295 } 296 297 static int erofs_iget_set_actor(struct inode *inode, void *opaque) 298 { 299 const erofs_nid_t nid = *(erofs_nid_t *)opaque; 300 301 inode->i_ino = erofs_inode_hash(nid); 302 return 0; 303 } 304 305 static inline struct inode *erofs_iget_locked(struct super_block *sb, 306 erofs_nid_t nid) 307 { 308 const unsigned long hashval = erofs_inode_hash(nid); 309 310 return iget5_locked(sb, hashval, erofs_ilookup_test_actor, 311 erofs_iget_set_actor, &nid); 312 } 313 314 struct inode *erofs_iget(struct super_block *sb, 315 erofs_nid_t nid, 316 bool isdir) 317 { 318 struct inode *inode = erofs_iget_locked(sb, nid); 319 320 if (!inode) 321 return ERR_PTR(-ENOMEM); 322 323 if (inode->i_state & I_NEW) { 324 int err; 325 struct erofs_inode *vi = EROFS_I(inode); 326 327 vi->nid = nid; 328 329 err = erofs_fill_inode(inode, isdir); 330 if (!err) 331 unlock_new_inode(inode); 332 else { 333 iget_failed(inode); 334 inode = ERR_PTR(err); 335 } 336 } 337 return inode; 338 } 339 340 int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path, 341 struct kstat *stat, u32 request_mask, 342 unsigned int query_flags) 343 { 344 struct inode *const inode = d_inode(path->dentry); 345 346 if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout)) 347 stat->attributes |= STATX_ATTR_COMPRESSED; 348 349 stat->attributes |= STATX_ATTR_IMMUTABLE; 350 stat->attributes_mask |= (STATX_ATTR_COMPRESSED | 351 STATX_ATTR_IMMUTABLE); 352 353 generic_fillattr(&init_user_ns, inode, stat); 354 return 0; 355 } 356 357 const struct inode_operations erofs_generic_iops = { 358 .getattr = erofs_getattr, 359 .listxattr = erofs_listxattr, 360 .get_acl = erofs_get_acl, 361 }; 362 363 const struct inode_operations erofs_symlink_iops = { 364 .get_link = page_get_link, 365 .getattr = erofs_getattr, 366 .listxattr = erofs_listxattr, 367 .get_acl = erofs_get_acl, 368 }; 369 370 const struct inode_operations erofs_fast_symlink_iops = { 371 .get_link = simple_get_link, 372 .getattr = erofs_getattr, 373 .listxattr = erofs_listxattr, 374 .get_acl = erofs_get_acl, 375 }; 376