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