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