1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
2ac27a0ecSDave Kleikamp /*
3617ba13bSMingming Cao * linux/fs/ext4/fsync.c
4ac27a0ecSDave Kleikamp *
5ac27a0ecSDave Kleikamp * Copyright (C) 1993 Stephen Tweedie (sct@redhat.com)
6ac27a0ecSDave Kleikamp * from
7ac27a0ecSDave Kleikamp * Copyright (C) 1992 Remy Card (card@masi.ibp.fr)
8ac27a0ecSDave Kleikamp * Laboratoire MASI - Institut Blaise Pascal
9ac27a0ecSDave Kleikamp * Universite Pierre et Marie Curie (Paris VI)
10ac27a0ecSDave Kleikamp * from
11ac27a0ecSDave Kleikamp * linux/fs/minix/truncate.c Copyright (C) 1991, 1992 Linus Torvalds
12ac27a0ecSDave Kleikamp *
13617ba13bSMingming Cao * ext4fs fsync primitive
14ac27a0ecSDave Kleikamp *
15ac27a0ecSDave Kleikamp * Big-endian to little-endian byte-swapping/bitmaps by
16ac27a0ecSDave Kleikamp * David S. Miller (davem@caip.rutgers.edu), 1995
17ac27a0ecSDave Kleikamp *
18ac27a0ecSDave Kleikamp * Removed unnecessary code duplication for little endian machines
19ac27a0ecSDave Kleikamp * and excessive __inline__s.
20ac27a0ecSDave Kleikamp * Andi Kleen, 1997
21ac27a0ecSDave Kleikamp *
22ac27a0ecSDave Kleikamp * Major simplications and cleanup - we only need to do the metadata, because
23ac27a0ecSDave Kleikamp * we can depend on generic_block_fdatasync() to sync the data blocks.
24ac27a0ecSDave Kleikamp */
25ac27a0ecSDave Kleikamp
26ac27a0ecSDave Kleikamp #include <linux/time.h>
27ac27a0ecSDave Kleikamp #include <linux/fs.h>
28ac27a0ecSDave Kleikamp #include <linux/sched.h>
29ac27a0ecSDave Kleikamp #include <linux/writeback.h>
30d755fb38SEric Sandeen #include <linux/blkdev.h>
315b5b4ff8SRitesh Harjani (IBM) #include <linux/buffer_head.h>
329bffad1eSTheodore Ts'o
333dcf5451SChristoph Hellwig #include "ext4.h"
343dcf5451SChristoph Hellwig #include "ext4_jbd2.h"
35ac27a0ecSDave Kleikamp
369bffad1eSTheodore Ts'o #include <trace/events/ext4.h>
379bffad1eSTheodore Ts'o
38ac27a0ecSDave Kleikamp /*
3914ece102SFrank Mayhar * If we're not journaling and this is a just-created file, we have to
4014ece102SFrank Mayhar * sync our parent directory (if it was freshly created) since
4114ece102SFrank Mayhar * otherwise it will only be written by writeback, leaving a huge
4214ece102SFrank Mayhar * window during which a crash may lose the file. This may apply for
4314ece102SFrank Mayhar * the parent directory's parent as well, and so on recursively, if
4414ece102SFrank Mayhar * they are also freshly created.
4514ece102SFrank Mayhar */
ext4_sync_parent(struct inode * inode)460893ed45SCurt Wohlgemuth static int ext4_sync_parent(struct inode *inode)
4714ece102SFrank Mayhar {
4808adf452SEric Biggers struct dentry *dentry, *next;
490893ed45SCurt Wohlgemuth int ret = 0;
5014ece102SFrank Mayhar
51d59729f4STheodore Ts'o if (!ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY))
52d59729f4STheodore Ts'o return 0;
539f713878SAl Viro dentry = d_find_any_alias(inode);
54d59729f4STheodore Ts'o if (!dentry)
5508adf452SEric Biggers return 0;
5608adf452SEric Biggers while (ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) {
5708adf452SEric Biggers ext4_clear_inode_state(inode, EXT4_STATE_NEWENTRY);
5808adf452SEric Biggers
5908adf452SEric Biggers next = dget_parent(dentry);
60d59729f4STheodore Ts'o dput(dentry);
6108adf452SEric Biggers dentry = next;
6208adf452SEric Biggers inode = dentry->d_inode;
6308adf452SEric Biggers
646ae4c5a6SJan Kara /*
656ae4c5a6SJan Kara * The directory inode may have gone through rmdir by now. But
666ae4c5a6SJan Kara * the inode itself and its blocks are still allocated (we hold
6708adf452SEric Biggers * a reference to the inode via its dentry), so it didn't go
6808adf452SEric Biggers * through ext4_evict_inode()) and so we are safe to flush
6908adf452SEric Biggers * metadata blocks and the inode.
706ae4c5a6SJan Kara */
710893ed45SCurt Wohlgemuth ret = sync_mapping_buffers(inode->i_mapping);
720893ed45SCurt Wohlgemuth if (ret)
730893ed45SCurt Wohlgemuth break;
7464744e03SGuo Chao ret = sync_inode_metadata(inode, 1);
750893ed45SCurt Wohlgemuth if (ret)
760893ed45SCurt Wohlgemuth break;
7714ece102SFrank Mayhar }
7808adf452SEric Biggers dput(dentry);
790893ed45SCurt Wohlgemuth return ret;
8014ece102SFrank Mayhar }
8114ece102SFrank Mayhar
ext4_fsync_nojournal(struct file * file,loff_t start,loff_t end,int datasync,bool * needs_barrier)825b5b4ff8SRitesh Harjani (IBM) static int ext4_fsync_nojournal(struct file *file, loff_t start, loff_t end,
835b5b4ff8SRitesh Harjani (IBM) int datasync, bool *needs_barrier)
843eaf9cc6SMatthew Bobrowski {
855b5b4ff8SRitesh Harjani (IBM) struct inode *inode = file->f_inode;
865b5b4ff8SRitesh Harjani (IBM) int ret;
873eaf9cc6SMatthew Bobrowski
885b5b4ff8SRitesh Harjani (IBM) ret = generic_buffers_fsync_noflush(file, start, end, datasync);
893eaf9cc6SMatthew Bobrowski if (!ret)
903eaf9cc6SMatthew Bobrowski ret = ext4_sync_parent(inode);
913eaf9cc6SMatthew Bobrowski if (test_opt(inode->i_sb, BARRIER))
923eaf9cc6SMatthew Bobrowski *needs_barrier = true;
933eaf9cc6SMatthew Bobrowski
943eaf9cc6SMatthew Bobrowski return ret;
953eaf9cc6SMatthew Bobrowski }
963eaf9cc6SMatthew Bobrowski
ext4_fsync_journal(struct inode * inode,bool datasync,bool * needs_barrier)973eaf9cc6SMatthew Bobrowski static int ext4_fsync_journal(struct inode *inode, bool datasync,
983eaf9cc6SMatthew Bobrowski bool *needs_barrier)
993eaf9cc6SMatthew Bobrowski {
1003eaf9cc6SMatthew Bobrowski struct ext4_inode_info *ei = EXT4_I(inode);
1013eaf9cc6SMatthew Bobrowski journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
1023eaf9cc6SMatthew Bobrowski tid_t commit_tid = datasync ? ei->i_datasync_tid : ei->i_sync_tid;
1033eaf9cc6SMatthew Bobrowski
1041077b2d5SJan Kara /*
1051077b2d5SJan Kara * Fastcommit does not really support fsync on directories or other
1061077b2d5SJan Kara * special files. Force a full commit.
1071077b2d5SJan Kara */
1081077b2d5SJan Kara if (!S_ISREG(inode->i_mode))
1091077b2d5SJan Kara return ext4_force_commit(inode->i_sb);
1101077b2d5SJan Kara
1113eaf9cc6SMatthew Bobrowski if (journal->j_flags & JBD2_BARRIER &&
1123eaf9cc6SMatthew Bobrowski !jbd2_trans_will_send_data_barrier(journal, commit_tid))
1133eaf9cc6SMatthew Bobrowski *needs_barrier = true;
1143eaf9cc6SMatthew Bobrowski
115aa75f4d3SHarshad Shirwadkar return ext4_fc_commit(journal, commit_tid);
1163eaf9cc6SMatthew Bobrowski }
1173eaf9cc6SMatthew Bobrowski
11814ece102SFrank Mayhar /*
119617ba13bSMingming Cao * akpm: A new design for ext4_sync_file().
120ac27a0ecSDave Kleikamp *
121ac27a0ecSDave Kleikamp * This is only called from sys_fsync(), sys_fdatasync() and sys_msync().
122ac27a0ecSDave Kleikamp * There cannot be a transaction open by this task.
123ac27a0ecSDave Kleikamp * Another task could have dirtied this inode. Its data can be in any
124ac27a0ecSDave Kleikamp * state in the journalling system.
125ac27a0ecSDave Kleikamp *
126ac27a0ecSDave Kleikamp * What we do is just kick off a commit and wait on it. This will snapshot the
127ac27a0ecSDave Kleikamp * inode to disk.
128ac27a0ecSDave Kleikamp */
ext4_sync_file(struct file * file,loff_t start,loff_t end,int datasync)12902c24a82SJosef Bacik int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
130ac27a0ecSDave Kleikamp {
13137b10dd0SJan Kara int ret = 0, err;
13293628ffbSJan Kara bool needs_barrier = false;
1333eaf9cc6SMatthew Bobrowski struct inode *inode = file->f_mapping->host;
134ac27a0ecSDave Kleikamp
135eb8ab444SJan Kara if (unlikely(ext4_forced_shutdown(inode->i_sb)))
1360db1ff22STheodore Ts'o return -EIO;
1370db1ff22STheodore Ts'o
138837c23fbSChunguang Xu ASSERT(ext4_journal_current_handle() == NULL);
139ac27a0ecSDave Kleikamp
1400562e0baSJiaying Zhang trace_ext4_sync_file_enter(file, datasync);
141ede86cc4STheodore Ts'o
142bc98a42cSDavid Howells if (sb_rdonly(inode->i_sb)) {
143*95257987SJan Kara /* Make sure that we read updated s_ext4_flags value */
1444418e141SDmitry Monakhov smp_rmb();
145*95257987SJan Kara if (ext4_forced_shutdown(inode->i_sb))
1464418e141SDmitry Monakhov ret = -EROFS;
14792e6222dSJan Kara goto out;
1484418e141SDmitry Monakhov }
14937b10dd0SJan Kara
150*95257987SJan Kara if (!EXT4_SB(inode->i_sb)->s_journal) {
1515b5b4ff8SRitesh Harjani (IBM) ret = ext4_fsync_nojournal(file, start, end, datasync,
1525b5b4ff8SRitesh Harjani (IBM) &needs_barrier);
1535b5b4ff8SRitesh Harjani (IBM) if (needs_barrier)
1545b5b4ff8SRitesh Harjani (IBM) goto issue_flush;
1555b5b4ff8SRitesh Harjani (IBM) goto out;
1565b5b4ff8SRitesh Harjani (IBM) }
1575b5b4ff8SRitesh Harjani (IBM)
1588fdd60f2STheodore Ts'o ret = file_write_and_wait_range(file, start, end);
1598fdd60f2STheodore Ts'o if (ret)
1602be7d717SZhang Qilong goto out;
1613eaf9cc6SMatthew Bobrowski
162ac27a0ecSDave Kleikamp /*
163ac27a0ecSDave Kleikamp * The caller's filemap_fdatawrite()/wait will sync the data.
164b436b9beSJan Kara * Metadata is in the journal, we wait for proper transaction to
165b436b9beSJan Kara * commit here.
166ac27a0ecSDave Kleikamp */
1673eaf9cc6SMatthew Bobrowski ret = ext4_fsync_journal(inode, datasync, &needs_barrier);
168ac27a0ecSDave Kleikamp
1695b5b4ff8SRitesh Harjani (IBM) issue_flush:
170a4a39040STheodore Ts'o if (needs_barrier) {
171c6bf3f0eSChristoph Hellwig err = blkdev_issue_flush(inode->i_sb->s_bdev);
172a4a39040STheodore Ts'o if (!ret)
173a4a39040STheodore Ts'o ret = err;
174a4a39040STheodore Ts'o }
1750562e0baSJiaying Zhang out:
17695cb6713STheodore Ts'o err = file_check_and_advance_wb_err(file);
17795cb6713STheodore Ts'o if (ret == 0)
17895cb6713STheodore Ts'o ret = err;
1790562e0baSJiaying Zhang trace_ext4_sync_file_exit(inode, ret);
180ac27a0ecSDave Kleikamp return ret;
181ac27a0ecSDave Kleikamp }
182