1 /* 2 * Copyright (C) International Business Machines Corp., 2000-2004 3 * Portions Copyright (C) Christoph Hellwig, 2001-2002 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 13 * the GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20 #include <linux/fs.h> 21 #include <linux/mpage.h> 22 #include <linux/buffer_head.h> 23 #include <linux/pagemap.h> 24 #include <linux/quotaops.h> 25 #include <linux/uio.h> 26 #include <linux/writeback.h> 27 #include "jfs_incore.h" 28 #include "jfs_inode.h" 29 #include "jfs_filsys.h" 30 #include "jfs_imap.h" 31 #include "jfs_extent.h" 32 #include "jfs_unicode.h" 33 #include "jfs_debug.h" 34 #include "jfs_dmap.h" 35 36 37 struct inode *jfs_iget(struct super_block *sb, unsigned long ino) 38 { 39 struct inode *inode; 40 int ret; 41 42 inode = iget_locked(sb, ino); 43 if (!inode) 44 return ERR_PTR(-ENOMEM); 45 if (!(inode->i_state & I_NEW)) 46 return inode; 47 48 ret = diRead(inode); 49 if (ret < 0) { 50 iget_failed(inode); 51 return ERR_PTR(ret); 52 } 53 54 if (S_ISREG(inode->i_mode)) { 55 inode->i_op = &jfs_file_inode_operations; 56 inode->i_fop = &jfs_file_operations; 57 inode->i_mapping->a_ops = &jfs_aops; 58 } else if (S_ISDIR(inode->i_mode)) { 59 inode->i_op = &jfs_dir_inode_operations; 60 inode->i_fop = &jfs_dir_operations; 61 } else if (S_ISLNK(inode->i_mode)) { 62 if (inode->i_size >= IDATASIZE) { 63 inode->i_op = &page_symlink_inode_operations; 64 inode_nohighmem(inode); 65 inode->i_mapping->a_ops = &jfs_aops; 66 } else { 67 inode->i_op = &jfs_fast_symlink_inode_operations; 68 inode->i_link = JFS_IP(inode)->i_inline; 69 /* 70 * The inline data should be null-terminated, but 71 * don't let on-disk corruption crash the kernel 72 */ 73 inode->i_link[inode->i_size] = '\0'; 74 } 75 } else { 76 inode->i_op = &jfs_file_inode_operations; 77 init_special_inode(inode, inode->i_mode, inode->i_rdev); 78 } 79 unlock_new_inode(inode); 80 return inode; 81 } 82 83 /* 84 * Workhorse of both fsync & write_inode 85 */ 86 int jfs_commit_inode(struct inode *inode, int wait) 87 { 88 int rc = 0; 89 tid_t tid; 90 static int noisy = 5; 91 92 jfs_info("In jfs_commit_inode, inode = 0x%p", inode); 93 94 /* 95 * Don't commit if inode has been committed since last being 96 * marked dirty, or if it has been deleted. 97 */ 98 if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode)) 99 return 0; 100 101 if (isReadOnly(inode)) { 102 /* kernel allows writes to devices on read-only 103 * partitions and may think inode is dirty 104 */ 105 if (!special_file(inode->i_mode) && noisy) { 106 jfs_err("jfs_commit_inode(0x%p) called on read-only volume", 107 inode); 108 jfs_err("Is remount racy?"); 109 noisy--; 110 } 111 return 0; 112 } 113 114 tid = txBegin(inode->i_sb, COMMIT_INODE); 115 mutex_lock(&JFS_IP(inode)->commit_mutex); 116 117 /* 118 * Retest inode state after taking commit_mutex 119 */ 120 if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode)) 121 rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0); 122 123 txEnd(tid); 124 mutex_unlock(&JFS_IP(inode)->commit_mutex); 125 return rc; 126 } 127 128 int jfs_write_inode(struct inode *inode, struct writeback_control *wbc) 129 { 130 int wait = wbc->sync_mode == WB_SYNC_ALL; 131 132 if (inode->i_nlink == 0) 133 return 0; 134 /* 135 * If COMMIT_DIRTY is not set, the inode isn't really dirty. 136 * It has been committed since the last change, but was still 137 * on the dirty inode list. 138 */ 139 if (!test_cflag(COMMIT_Dirty, inode)) { 140 /* Make sure committed changes hit the disk */ 141 jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait); 142 return 0; 143 } 144 145 if (jfs_commit_inode(inode, wait)) { 146 jfs_err("jfs_write_inode: jfs_commit_inode failed!"); 147 return -EIO; 148 } else 149 return 0; 150 } 151 152 void jfs_evict_inode(struct inode *inode) 153 { 154 struct jfs_inode_info *ji = JFS_IP(inode); 155 156 jfs_info("In jfs_evict_inode, inode = 0x%p", inode); 157 158 if (!inode->i_nlink && !is_bad_inode(inode)) { 159 dquot_initialize(inode); 160 161 if (JFS_IP(inode)->fileset == FILESYSTEM_I) { 162 truncate_inode_pages_final(&inode->i_data); 163 164 if (test_cflag(COMMIT_Freewmap, inode)) 165 jfs_free_zero_link(inode); 166 167 diFree(inode); 168 169 /* 170 * Free the inode from the quota allocation. 171 */ 172 dquot_free_inode(inode); 173 } 174 } else { 175 truncate_inode_pages_final(&inode->i_data); 176 } 177 clear_inode(inode); 178 dquot_drop(inode); 179 180 BUG_ON(!list_empty(&ji->anon_inode_list)); 181 182 spin_lock_irq(&ji->ag_lock); 183 if (ji->active_ag != -1) { 184 struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap; 185 atomic_dec(&bmap->db_active[ji->active_ag]); 186 ji->active_ag = -1; 187 } 188 spin_unlock_irq(&ji->ag_lock); 189 } 190 191 void jfs_dirty_inode(struct inode *inode, int flags) 192 { 193 static int noisy = 5; 194 195 if (isReadOnly(inode)) { 196 if (!special_file(inode->i_mode) && noisy) { 197 /* kernel allows writes to devices on read-only 198 * partitions and may try to mark inode dirty 199 */ 200 jfs_err("jfs_dirty_inode called on read-only volume"); 201 jfs_err("Is remount racy?"); 202 noisy--; 203 } 204 return; 205 } 206 207 set_cflag(COMMIT_Dirty, inode); 208 } 209 210 int jfs_get_block(struct inode *ip, sector_t lblock, 211 struct buffer_head *bh_result, int create) 212 { 213 s64 lblock64 = lblock; 214 int rc = 0; 215 xad_t xad; 216 s64 xaddr; 217 int xflag; 218 s32 xlen = bh_result->b_size >> ip->i_blkbits; 219 220 /* 221 * Take appropriate lock on inode 222 */ 223 if (create) 224 IWRITE_LOCK(ip, RDWRLOCK_NORMAL); 225 else 226 IREAD_LOCK(ip, RDWRLOCK_NORMAL); 227 228 if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) && 229 (!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) && 230 xaddr) { 231 if (xflag & XAD_NOTRECORDED) { 232 if (!create) 233 /* 234 * Allocated but not recorded, read treats 235 * this as a hole 236 */ 237 goto unlock; 238 #ifdef _JFS_4K 239 XADoffset(&xad, lblock64); 240 XADlength(&xad, xlen); 241 XADaddress(&xad, xaddr); 242 #else /* _JFS_4K */ 243 /* 244 * As long as block size = 4K, this isn't a problem. 245 * We should mark the whole page not ABNR, but how 246 * will we know to mark the other blocks BH_New? 247 */ 248 BUG(); 249 #endif /* _JFS_4K */ 250 rc = extRecord(ip, &xad); 251 if (rc) 252 goto unlock; 253 set_buffer_new(bh_result); 254 } 255 256 map_bh(bh_result, ip->i_sb, xaddr); 257 bh_result->b_size = xlen << ip->i_blkbits; 258 goto unlock; 259 } 260 if (!create) 261 goto unlock; 262 263 /* 264 * Allocate a new block 265 */ 266 #ifdef _JFS_4K 267 if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad))) 268 goto unlock; 269 rc = extAlloc(ip, xlen, lblock64, &xad, false); 270 if (rc) 271 goto unlock; 272 273 set_buffer_new(bh_result); 274 map_bh(bh_result, ip->i_sb, addressXAD(&xad)); 275 bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits; 276 277 #else /* _JFS_4K */ 278 /* 279 * We need to do whatever it takes to keep all but the last buffers 280 * in 4K pages - see jfs_write.c 281 */ 282 BUG(); 283 #endif /* _JFS_4K */ 284 285 unlock: 286 /* 287 * Release lock on inode 288 */ 289 if (create) 290 IWRITE_UNLOCK(ip); 291 else 292 IREAD_UNLOCK(ip); 293 return rc; 294 } 295 296 static int jfs_writepage(struct page *page, struct writeback_control *wbc) 297 { 298 return block_write_full_page(page, jfs_get_block, wbc); 299 } 300 301 static int jfs_writepages(struct address_space *mapping, 302 struct writeback_control *wbc) 303 { 304 return mpage_writepages(mapping, wbc, jfs_get_block); 305 } 306 307 static int jfs_readpage(struct file *file, struct page *page) 308 { 309 return mpage_readpage(page, jfs_get_block); 310 } 311 312 static int jfs_readpages(struct file *file, struct address_space *mapping, 313 struct list_head *pages, unsigned nr_pages) 314 { 315 return mpage_readpages(mapping, pages, nr_pages, jfs_get_block); 316 } 317 318 static void jfs_write_failed(struct address_space *mapping, loff_t to) 319 { 320 struct inode *inode = mapping->host; 321 322 if (to > inode->i_size) { 323 truncate_pagecache(inode, inode->i_size); 324 jfs_truncate(inode); 325 } 326 } 327 328 static int jfs_write_begin(struct file *file, struct address_space *mapping, 329 loff_t pos, unsigned len, unsigned flags, 330 struct page **pagep, void **fsdata) 331 { 332 int ret; 333 334 ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata, 335 jfs_get_block); 336 if (unlikely(ret)) 337 jfs_write_failed(mapping, pos + len); 338 339 return ret; 340 } 341 342 static sector_t jfs_bmap(struct address_space *mapping, sector_t block) 343 { 344 return generic_block_bmap(mapping, block, jfs_get_block); 345 } 346 347 static ssize_t jfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) 348 { 349 struct file *file = iocb->ki_filp; 350 struct address_space *mapping = file->f_mapping; 351 struct inode *inode = file->f_mapping->host; 352 size_t count = iov_iter_count(iter); 353 ssize_t ret; 354 355 ret = blockdev_direct_IO(iocb, inode, iter, jfs_get_block); 356 357 /* 358 * In case of error extending write may have instantiated a few 359 * blocks outside i_size. Trim these off again. 360 */ 361 if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) { 362 loff_t isize = i_size_read(inode); 363 loff_t end = iocb->ki_pos + count; 364 365 if (end > isize) 366 jfs_write_failed(mapping, end); 367 } 368 369 return ret; 370 } 371 372 const struct address_space_operations jfs_aops = { 373 .readpage = jfs_readpage, 374 .readpages = jfs_readpages, 375 .writepage = jfs_writepage, 376 .writepages = jfs_writepages, 377 .write_begin = jfs_write_begin, 378 .write_end = nobh_write_end, 379 .bmap = jfs_bmap, 380 .direct_IO = jfs_direct_IO, 381 }; 382 383 /* 384 * Guts of jfs_truncate. Called with locks already held. Can be called 385 * with directory for truncating directory index table. 386 */ 387 void jfs_truncate_nolock(struct inode *ip, loff_t length) 388 { 389 loff_t newsize; 390 tid_t tid; 391 392 ASSERT(length >= 0); 393 394 if (test_cflag(COMMIT_Nolink, ip)) { 395 xtTruncate(0, ip, length, COMMIT_WMAP); 396 return; 397 } 398 399 do { 400 tid = txBegin(ip->i_sb, 0); 401 402 /* 403 * The commit_mutex cannot be taken before txBegin. 404 * txBegin may block and there is a chance the inode 405 * could be marked dirty and need to be committed 406 * before txBegin unblocks 407 */ 408 mutex_lock(&JFS_IP(ip)->commit_mutex); 409 410 newsize = xtTruncate(tid, ip, length, 411 COMMIT_TRUNCATE | COMMIT_PWMAP); 412 if (newsize < 0) { 413 txEnd(tid); 414 mutex_unlock(&JFS_IP(ip)->commit_mutex); 415 break; 416 } 417 418 ip->i_mtime = ip->i_ctime = current_time(ip); 419 mark_inode_dirty(ip); 420 421 txCommit(tid, 1, &ip, 0); 422 txEnd(tid); 423 mutex_unlock(&JFS_IP(ip)->commit_mutex); 424 } while (newsize > length); /* Truncate isn't always atomic */ 425 } 426 427 void jfs_truncate(struct inode *ip) 428 { 429 jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size); 430 431 nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block); 432 433 IWRITE_LOCK(ip, RDWRLOCK_NORMAL); 434 jfs_truncate_nolock(ip, ip->i_size); 435 IWRITE_UNLOCK(ip); 436 } 437