]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/ext3/fsync.c | |
3 | * | |
4 | * Copyright (C) 1993 Stephen Tweedie (sct@redhat.com) | |
5 | * from | |
6 | * Copyright (C) 1992 Remy Card (card@masi.ibp.fr) | |
7 | * Laboratoire MASI - Institut Blaise Pascal | |
8 | * Universite Pierre et Marie Curie (Paris VI) | |
9 | * from | |
10 | * linux/fs/minix/truncate.c Copyright (C) 1991, 1992 Linus Torvalds | |
ae6ddcc5 | 11 | * |
1da177e4 LT |
12 | * ext3fs fsync primitive |
13 | * | |
14 | * Big-endian to little-endian byte-swapping/bitmaps by | |
15 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
ae6ddcc5 | 16 | * |
1da177e4 | 17 | * Removed unnecessary code duplication for little endian machines |
ae6ddcc5 | 18 | * and excessive __inline__s. |
1da177e4 LT |
19 | * Andi Kleen, 1997 |
20 | * | |
21 | * Major simplications and cleanup - we only need to do the metadata, because | |
22 | * we can depend on generic_block_fdatasync() to sync the data blocks. | |
23 | */ | |
24 | ||
25 | #include <linux/time.h> | |
56fcad29 | 26 | #include <linux/blkdev.h> |
1da177e4 LT |
27 | #include <linux/fs.h> |
28 | #include <linux/sched.h> | |
29 | #include <linux/writeback.h> | |
30 | #include <linux/jbd.h> | |
31 | #include <linux/ext3_fs.h> | |
32 | #include <linux/ext3_jbd.h> | |
33 | ||
34 | /* | |
35 | * akpm: A new design for ext3_sync_file(). | |
36 | * | |
37 | * This is only called from sys_fsync(), sys_fdatasync() and sys_msync(). | |
38 | * There cannot be a transaction open by this task. | |
39 | * Another task could have dirtied this inode. Its data can be in any | |
40 | * state in the journalling system. | |
41 | * | |
42 | * What we do is just kick off a commit and wait on it. This will snapshot the | |
43 | * inode to disk. | |
44 | */ | |
45 | ||
02c24a82 | 46 | int ext3_sync_file(struct file *file, loff_t start, loff_t end, int datasync) |
1da177e4 | 47 | { |
7ea80859 | 48 | struct inode *inode = file->f_mapping->host; |
fe8bc91c JK |
49 | struct ext3_inode_info *ei = EXT3_I(inode); |
50 | journal_t *journal = EXT3_SB(inode->i_sb)->s_journal; | |
52779708 | 51 | int ret, needs_barrier = 0; |
fe8bc91c JK |
52 | tid_t commit_tid; |
53 | ||
54 | if (inode->i_sb->s_flags & MS_RDONLY) | |
55 | return 0; | |
1da177e4 | 56 | |
02c24a82 JB |
57 | ret = filemap_write_and_wait_range(inode->i_mapping, start, end); |
58 | if (ret) | |
59 | return ret; | |
60 | ||
61 | /* | |
62 | * Taking the mutex here just to keep consistent with how fsync was | |
63 | * called previously, however it looks like we don't need to take | |
64 | * i_mutex at all. | |
65 | */ | |
66 | mutex_lock(&inode->i_mutex); | |
67 | ||
c80544dc | 68 | J_ASSERT(ext3_journal_current_handle() == NULL); |
1da177e4 LT |
69 | |
70 | /* | |
fe8bc91c | 71 | * data=writeback,ordered: |
1da177e4 | 72 | * The caller's filemap_fdatawrite()/wait will sync the data. |
fe8bc91c JK |
73 | * Metadata is in the journal, we wait for a proper transaction |
74 | * to commit here. | |
1da177e4 LT |
75 | * |
76 | * data=journal: | |
77 | * filemap_fdatawrite won't do anything (the buffers are clean). | |
78 | * ext3_force_commit will write the file data into the journal and | |
79 | * will wait on that. | |
80 | * filemap_fdatawait() will encounter a ton of newly-dirtied pages | |
81 | * (they were dirtied by commit). But that's OK - the blocks are | |
82 | * safe in-journal, which is all fsync() needs to ensure. | |
83 | */ | |
02c24a82 JB |
84 | if (ext3_should_journal_data(inode)) { |
85 | mutex_unlock(&inode->i_mutex); | |
52779708 | 86 | return ext3_force_commit(inode->i_sb); |
02c24a82 | 87 | } |
1da177e4 | 88 | |
fe8bc91c JK |
89 | if (datasync) |
90 | commit_tid = atomic_read(&ei->i_datasync_tid); | |
91 | else | |
92 | commit_tid = atomic_read(&ei->i_sync_tid); | |
3d61f75e | 93 | |
52779708 JK |
94 | if (test_opt(inode->i_sb, BARRIER) && |
95 | !journal_trans_will_send_data_barrier(journal, commit_tid)) | |
96 | needs_barrier = 1; | |
97 | log_start_commit(journal, commit_tid); | |
98 | ret = log_wait_commit(journal, commit_tid); | |
fe8bc91c | 99 | |
56fcad29 JK |
100 | /* |
101 | * In case we didn't commit a transaction, we have to flush | |
102 | * disk caches manually so that data really is on persistent | |
103 | * storage | |
104 | */ | |
52779708 | 105 | if (needs_barrier) |
dd3932ed | 106 | blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); |
02c24a82 | 107 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
108 | return ret; |
109 | } |