1 /* 2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README 3 */ 4 5 #include <linux/time.h> 6 #include "reiserfs.h" 7 #include "acl.h" 8 #include "xattr.h" 9 #include <linux/uaccess.h> 10 #include <linux/pagemap.h> 11 #include <linux/swap.h> 12 #include <linux/writeback.h> 13 #include <linux/blkdev.h> 14 #include <linux/buffer_head.h> 15 #include <linux/quotaops.h> 16 17 /* 18 * We pack the tails of files on file close, not at the time they are written. 19 * This implies an unnecessary copy of the tail and an unnecessary indirect item 20 * insertion/balancing, for files that are written in one write. 21 * It avoids unnecessary tail packings (balances) for files that are written in 22 * multiple writes and are small enough to have tails. 23 * 24 * file_release is called by the VFS layer when the file is closed. If 25 * this is the last open file descriptor, and the file 26 * small enough to have a tail, and the tail is currently in an 27 * unformatted node, the tail is converted back into a direct item. 28 * 29 * We use reiserfs_truncate_file to pack the tail, since it already has 30 * all the conditions coded. 31 */ 32 static int reiserfs_file_release(struct inode *inode, struct file *filp) 33 { 34 35 struct reiserfs_transaction_handle th; 36 int err; 37 int jbegin_failure = 0; 38 39 BUG_ON(!S_ISREG(inode->i_mode)); 40 41 if (!atomic_dec_and_mutex_lock(&REISERFS_I(inode)->openers, 42 &REISERFS_I(inode)->tailpack)) 43 return 0; 44 45 /* fast out for when nothing needs to be done */ 46 if ((!(REISERFS_I(inode)->i_flags & i_pack_on_close_mask) || 47 !tail_has_to_be_packed(inode)) && 48 REISERFS_I(inode)->i_prealloc_count <= 0) { 49 mutex_unlock(&REISERFS_I(inode)->tailpack); 50 return 0; 51 } 52 53 reiserfs_write_lock(inode->i_sb); 54 /* 55 * freeing preallocation only involves relogging blocks that 56 * are already in the current transaction. preallocation gets 57 * freed at the end of each transaction, so it is impossible for 58 * us to log any additional blocks (including quota blocks) 59 */ 60 err = journal_begin(&th, inode->i_sb, 1); 61 if (err) { 62 /* 63 * uh oh, we can't allow the inode to go away while there 64 * is still preallocation blocks pending. Try to join the 65 * aborted transaction 66 */ 67 jbegin_failure = err; 68 err = journal_join_abort(&th, inode->i_sb); 69 70 if (err) { 71 /* 72 * hmpf, our choices here aren't good. We can pin 73 * the inode which will disallow unmount from ever 74 * happening, we can do nothing, which will corrupt 75 * random memory on unmount, or we can forcibly 76 * remove the file from the preallocation list, which 77 * will leak blocks on disk. Lets pin the inode 78 * and let the admin know what is going on. 79 */ 80 igrab(inode); 81 reiserfs_warning(inode->i_sb, "clm-9001", 82 "pinning inode %lu because the " 83 "preallocation can't be freed", 84 inode->i_ino); 85 goto out; 86 } 87 } 88 reiserfs_update_inode_transaction(inode); 89 90 #ifdef REISERFS_PREALLOCATE 91 reiserfs_discard_prealloc(&th, inode); 92 #endif 93 err = journal_end(&th); 94 95 /* copy back the error code from journal_begin */ 96 if (!err) 97 err = jbegin_failure; 98 99 if (!err && 100 (REISERFS_I(inode)->i_flags & i_pack_on_close_mask) && 101 tail_has_to_be_packed(inode)) { 102 103 /* 104 * if regular file is released by last holder and it has been 105 * appended (we append by unformatted node only) or its direct 106 * item(s) had to be converted, then it may have to be 107 * indirect2direct converted 108 */ 109 err = reiserfs_truncate_file(inode, 0); 110 } 111 out: 112 reiserfs_write_unlock(inode->i_sb); 113 mutex_unlock(&REISERFS_I(inode)->tailpack); 114 return err; 115 } 116 117 static int reiserfs_file_open(struct inode *inode, struct file *file) 118 { 119 int err = dquot_file_open(inode, file); 120 121 /* somebody might be tailpacking on final close; wait for it */ 122 if (!atomic_inc_not_zero(&REISERFS_I(inode)->openers)) { 123 mutex_lock(&REISERFS_I(inode)->tailpack); 124 atomic_inc(&REISERFS_I(inode)->openers); 125 mutex_unlock(&REISERFS_I(inode)->tailpack); 126 } 127 return err; 128 } 129 130 void reiserfs_vfs_truncate_file(struct inode *inode) 131 { 132 mutex_lock(&REISERFS_I(inode)->tailpack); 133 reiserfs_truncate_file(inode, 1); 134 mutex_unlock(&REISERFS_I(inode)->tailpack); 135 } 136 137 /* Sync a reiserfs file. */ 138 139 /* 140 * FIXME: sync_mapping_buffers() never has anything to sync. Can 141 * be removed... 142 */ 143 144 static int reiserfs_sync_file(struct file *filp, loff_t start, loff_t end, 145 int datasync) 146 { 147 struct inode *inode = filp->f_mapping->host; 148 int err; 149 int barrier_done; 150 151 err = file_write_and_wait_range(filp, start, end); 152 if (err) 153 return err; 154 155 inode_lock(inode); 156 BUG_ON(!S_ISREG(inode->i_mode)); 157 err = sync_mapping_buffers(inode->i_mapping); 158 reiserfs_write_lock(inode->i_sb); 159 barrier_done = reiserfs_commit_for_inode(inode); 160 reiserfs_write_unlock(inode->i_sb); 161 if (barrier_done != 1 && reiserfs_barrier_flush(inode->i_sb)) 162 blkdev_issue_flush(inode->i_sb->s_bdev); 163 inode_unlock(inode); 164 if (barrier_done < 0) 165 return barrier_done; 166 return (err < 0) ? -EIO : 0; 167 } 168 169 /* taken fs/buffer.c:__block_commit_write */ 170 int reiserfs_commit_page(struct inode *inode, struct page *page, 171 unsigned from, unsigned to) 172 { 173 unsigned block_start, block_end; 174 int partial = 0; 175 unsigned blocksize; 176 struct buffer_head *bh, *head; 177 unsigned long i_size_index = inode->i_size >> PAGE_SHIFT; 178 int new; 179 int logit = reiserfs_file_data_log(inode); 180 struct super_block *s = inode->i_sb; 181 int bh_per_page = PAGE_SIZE / s->s_blocksize; 182 struct reiserfs_transaction_handle th; 183 int ret = 0; 184 185 th.t_trans_id = 0; 186 blocksize = i_blocksize(inode); 187 188 if (logit) { 189 reiserfs_write_lock(s); 190 ret = journal_begin(&th, s, bh_per_page + 1); 191 if (ret) 192 goto drop_write_lock; 193 reiserfs_update_inode_transaction(inode); 194 } 195 for (bh = head = page_buffers(page), block_start = 0; 196 bh != head || !block_start; 197 block_start = block_end, bh = bh->b_this_page) { 198 199 new = buffer_new(bh); 200 clear_buffer_new(bh); 201 block_end = block_start + blocksize; 202 if (block_end <= from || block_start >= to) { 203 if (!buffer_uptodate(bh)) 204 partial = 1; 205 } else { 206 set_buffer_uptodate(bh); 207 if (logit) { 208 reiserfs_prepare_for_journal(s, bh, 1); 209 journal_mark_dirty(&th, bh); 210 } else if (!buffer_dirty(bh)) { 211 mark_buffer_dirty(bh); 212 /* 213 * do data=ordered on any page past the end 214 * of file and any buffer marked BH_New. 215 */ 216 if (reiserfs_data_ordered(inode->i_sb) && 217 (new || page->index >= i_size_index)) { 218 reiserfs_add_ordered_list(inode, bh); 219 } 220 } 221 } 222 } 223 if (logit) { 224 ret = journal_end(&th); 225 drop_write_lock: 226 reiserfs_write_unlock(s); 227 } 228 /* 229 * If this is a partial write which happened to make all buffers 230 * uptodate then we can optimize away a bogus readpage() for 231 * the next read(). Here we 'discover' whether the page went 232 * uptodate as a result of this (potentially partial) write. 233 */ 234 if (!partial) 235 SetPageUptodate(page); 236 return ret; 237 } 238 239 const struct file_operations reiserfs_file_operations = { 240 .unlocked_ioctl = reiserfs_ioctl, 241 #ifdef CONFIG_COMPAT 242 .compat_ioctl = reiserfs_compat_ioctl, 243 #endif 244 .mmap = generic_file_mmap, 245 .open = reiserfs_file_open, 246 .release = reiserfs_file_release, 247 .fsync = reiserfs_sync_file, 248 .read_iter = generic_file_read_iter, 249 .write_iter = generic_file_write_iter, 250 .splice_read = generic_file_splice_read, 251 .splice_write = iter_file_splice_write, 252 .llseek = generic_file_llseek, 253 }; 254 255 const struct inode_operations reiserfs_file_inode_operations = { 256 .setattr = reiserfs_setattr, 257 .listxattr = reiserfs_listxattr, 258 .permission = reiserfs_permission, 259 .get_acl = reiserfs_get_acl, 260 .set_acl = reiserfs_set_acl, 261 .fileattr_get = reiserfs_fileattr_get, 262 .fileattr_set = reiserfs_fileattr_set, 263 }; 264