ext4: provide wrappers for transaction reservation calls
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c
index bd25e78..72a3600 100644
--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c
@@ -38,31 +38,43 @@
/*
* Wrappers for jbd2_journal_start/end.
*/
-handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line,
- int type, int nblocks)
+static int ext4_journal_check_start(struct super_block *sb)
{
journal_t *journal;
might_sleep();
-
- trace_ext4_journal_start(sb, nblocks, _RET_IP_);
if (sb->s_flags & MS_RDONLY)
- return ERR_PTR(-EROFS);
-
+ return -EROFS;
WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
journal = EXT4_SB(sb)->s_journal;
- if (!journal)
- return ext4_get_nojournal();
/*
* Special case here: if the journal has aborted behind our
* backs (eg. EIO in the commit thread), then we still need to
* take the FS itself readonly cleanly.
*/
- if (is_journal_aborted(journal)) {
+ if (journal && is_journal_aborted(journal)) {
ext4_abort(sb, "Detected aborted journal");
- return ERR_PTR(-EROFS);
+ return -EROFS;
}
- return jbd2__journal_start(journal, nblocks, 0, GFP_NOFS, type, line);
+ return 0;
+}
+
+handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line,
+ int type, int blocks, int rsv_blocks)
+{
+ journal_t *journal;
+ int err;
+
+ trace_ext4_journal_start(sb, blocks, rsv_blocks, _RET_IP_);
+ err = ext4_journal_check_start(sb);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ journal = EXT4_SB(sb)->s_journal;
+ if (!journal)
+ return ext4_get_nojournal();
+ return jbd2__journal_start(journal, blocks, rsv_blocks, GFP_NOFS,
+ type, line);
}
int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
@@ -86,6 +98,30 @@
return err;
}
+handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
+ int type)
+{
+ struct super_block *sb;
+ int err;
+
+ if (!ext4_handle_valid(handle))
+ return ext4_get_nojournal();
+
+ sb = handle->h_journal->j_private;
+ trace_ext4_journal_start_reserved(sb, handle->h_buffer_credits,
+ _RET_IP_);
+ err = ext4_journal_check_start(sb);
+ if (err < 0) {
+ jbd2_journal_free_reserved(handle);
+ return ERR_PTR(err);
+ }
+
+ err = jbd2_journal_start_reserved(handle, type, line);
+ if (err < 0)
+ return ERR_PTR(err);
+ return handle;
+}
+
void ext4_journal_abort_handle(const char *caller, unsigned int line,
const char *err_fn, struct buffer_head *bh,
handle_t *handle, int err)