xref: /linux/fs/ext4/ext4_jbd2.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * Interface between ext4 and JBD
3  */
4 
5 #include "ext4_jbd2.h"
6 
7 #include <trace/events/ext4.h>
8 
9 int __ext4_journal_get_write_access(const char *where, unsigned int line,
10 				    handle_t *handle, struct buffer_head *bh)
11 {
12 	int err = 0;
13 
14 	if (ext4_handle_valid(handle)) {
15 		err = jbd2_journal_get_write_access(handle, bh);
16 		if (err)
17 			ext4_journal_abort_handle(where, line, __func__, bh,
18 						  handle, err);
19 	}
20 	return err;
21 }
22 
23 /*
24  * The ext4 forget function must perform a revoke if we are freeing data
25  * which has been journaled.  Metadata (eg. indirect blocks) must be
26  * revoked in all cases.
27  *
28  * "bh" may be NULL: a metadata block may have been freed from memory
29  * but there may still be a record of it in the journal, and that record
30  * still needs to be revoked.
31  *
32  * If the handle isn't valid we're not journaling, but we still need to
33  * call into ext4_journal_revoke() to put the buffer head.
34  */
35 int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
36 		  int is_metadata, struct inode *inode,
37 		  struct buffer_head *bh, ext4_fsblk_t blocknr)
38 {
39 	int err;
40 
41 	might_sleep();
42 
43 	trace_ext4_forget(inode, is_metadata, blocknr);
44 	BUFFER_TRACE(bh, "enter");
45 
46 	jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
47 		  "data mode %x\n",
48 		  bh, is_metadata, inode->i_mode,
49 		  test_opt(inode->i_sb, DATA_FLAGS));
50 
51 	/* In the no journal case, we can just do a bforget and return */
52 	if (!ext4_handle_valid(handle)) {
53 		bforget(bh);
54 		return 0;
55 	}
56 
57 	/* Never use the revoke function if we are doing full data
58 	 * journaling: there is no need to, and a V1 superblock won't
59 	 * support it.  Otherwise, only skip the revoke on un-journaled
60 	 * data blocks. */
61 
62 	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ||
63 	    (!is_metadata && !ext4_should_journal_data(inode))) {
64 		if (bh) {
65 			BUFFER_TRACE(bh, "call jbd2_journal_forget");
66 			err = jbd2_journal_forget(handle, bh);
67 			if (err)
68 				ext4_journal_abort_handle(where, line, __func__,
69 							  bh, handle, err);
70 			return err;
71 		}
72 		return 0;
73 	}
74 
75 	/*
76 	 * data!=journal && (is_metadata || should_journal_data(inode))
77 	 */
78 	BUFFER_TRACE(bh, "call jbd2_journal_revoke");
79 	err = jbd2_journal_revoke(handle, blocknr, bh);
80 	if (err) {
81 		ext4_journal_abort_handle(where, line, __func__,
82 					  bh, handle, err);
83 		__ext4_abort(inode->i_sb, where, line,
84 			   "error %d when attempting revoke", err);
85 	}
86 	BUFFER_TRACE(bh, "exit");
87 	return err;
88 }
89 
90 int __ext4_journal_get_create_access(const char *where, unsigned int line,
91 				handle_t *handle, struct buffer_head *bh)
92 {
93 	int err = 0;
94 
95 	if (ext4_handle_valid(handle)) {
96 		err = jbd2_journal_get_create_access(handle, bh);
97 		if (err)
98 			ext4_journal_abort_handle(where, line, __func__,
99 						  bh, handle, err);
100 	}
101 	return err;
102 }
103 
104 int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
105 				 handle_t *handle, struct inode *inode,
106 				 struct buffer_head *bh)
107 {
108 	int err = 0;
109 
110 	if (ext4_handle_valid(handle)) {
111 		err = jbd2_journal_dirty_metadata(handle, bh);
112 		if (err) {
113 			/* Errors can only happen if there is a bug */
114 			handle->h_err = err;
115 			__ext4_journal_stop(where, line, handle);
116 		}
117 	} else {
118 		if (inode)
119 			mark_buffer_dirty_inode(bh, inode);
120 		else
121 			mark_buffer_dirty(bh);
122 		if (inode && inode_needs_sync(inode)) {
123 			sync_dirty_buffer(bh);
124 			if (buffer_req(bh) && !buffer_uptodate(bh)) {
125 				struct ext4_super_block *es;
126 
127 				es = EXT4_SB(inode->i_sb)->s_es;
128 				es->s_last_error_block =
129 					cpu_to_le64(bh->b_blocknr);
130 				ext4_error_inode(inode, where, line,
131 						 bh->b_blocknr,
132 					"IO error syncing itable block");
133 				err = -EIO;
134 			}
135 		}
136 	}
137 	return err;
138 }
139 
140 int __ext4_handle_dirty_super(const char *where, unsigned int line,
141 			      handle_t *handle, struct super_block *sb)
142 {
143 	struct buffer_head *bh = EXT4_SB(sb)->s_sbh;
144 	int err = 0;
145 
146 	ext4_superblock_csum_set(sb);
147 	if (ext4_handle_valid(handle)) {
148 		err = jbd2_journal_dirty_metadata(handle, bh);
149 		if (err)
150 			ext4_journal_abort_handle(where, line, __func__,
151 						  bh, handle, err);
152 	} else
153 		mark_buffer_dirty(bh);
154 	return err;
155 }
156