This patch allows file systems to turn fast commits on and thereby
restrict the normal journalling space to total journal blocks minus
JBD2_FAST_COMMIT_BLOCKS. Fast commits are not actually performed, just
the interface to turn fast commits on is opened.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@xxxxxxxxx>
---
Changelog:
V2: No changes since V1
---
fs/ext4/super.c | 3 ++-
fs/jbd2/journal.c | 39 ++++++++++++++++++++++++++++++++-------
fs/ocfs2/journal.c | 4 ++--
include/linux/jbd2.h | 2 +-
4 files changed, 37 insertions(+), 11 deletions(-)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index e376ac040cce..81c3ec165822 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4933,7 +4933,8 @@ static int ext4_load_journal(struct super_block *sb,
if (save)
memcpy(save, ((char *) es) +
EXT4_S_ERR_START, EXT4_S_ERR_LEN);
- err = jbd2_journal_load(journal);
+ err = jbd2_journal_load(journal,
+ test_opt2(sb, JOURNAL_FAST_COMMIT));
if (save)
memcpy(((char *) es) + EXT4_S_ERR_START,
save, EXT4_S_ERR_LEN);
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 953990eb70a9..59ad709154a3 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1159,12 +1159,15 @@ static journal_t *journal_init_common(struct block_device *bdev,
journal->j_blk_offset = start;
journal->j_maxlen = len;
n = journal->j_blocksize / sizeof(journal_block_tag_t);
- journal->j_wbufsize = n;
+ journal->j_wbufsize = n - JBD2_FAST_COMMIT_BLOCKS;
journal->j_wbuf = kmalloc_array(n, sizeof(struct buffer_head *),
GFP_KERNEL);
if (!journal->j_wbuf)
goto err_cleanup;
+ journal->j_fc_wbuf = &journal->j_wbuf[journal->j_wbufsize];
+ journal->j_fc_wbufsize = JBD2_FAST_COMMIT_BLOCKS;
+
bh = getblk_unmovable(journal->j_dev, start, journal->j_blocksize);
if (!bh) {
pr_err("%s: Cannot get buffer for journal superblock\n",
@@ -1297,11 +1300,19 @@ static int journal_reset(journal_t *journal)
}
journal->j_first = first;
- journal->j_last = last;
- journal->j_head = first;
- journal->j_tail = first;
- journal->j_free = last - first;
+ if (jbd2_has_feature_fast_commit(journal)) {
+ journal->j_last_fc = last;
+ journal->j_last = last - JBD2_FAST_COMMIT_BLOCKS;
+ journal->j_first_fc = journal->j_last + 1;
+ journal->j_fc_off = 0;
+ } else {
+ journal->j_last = last;
+ }
+
+ journal->j_head = journal->j_first;
+ journal->j_tail = journal->j_first;
+ journal->j_free = journal->j_last - journal->j_first;
journal->j_tail_sequence = journal->j_transaction_sequence;
journal->j_commit_sequence = journal->j_transaction_sequence - 1;
@@ -1626,9 +1637,17 @@ static int load_superblock(journal_t *journal)
journal->j_tail_sequence = be32_to_cpu(sb->s_sequence);
journal->j_tail = be32_to_cpu(sb->s_start);
journal->j_first = be32_to_cpu(sb->s_first);
- journal->j_last = be32_to_cpu(sb->s_maxlen);
journal->j_errno = be32_to_cpu(sb->s_errno);
+ if (jbd2_has_feature_fast_commit(journal)) {
+ journal->j_last_fc = be32_to_cpu(sb->s_maxlen);
+ journal->j_last = journal->j_last_fc - JBD2_FAST_COMMIT_BLOCKS;
+ journal->j_first_fc = journal->j_last + 1;
+ journal->j_fc_off = 0;
+ } else {
+ journal->j_last = be32_to_cpu(sb->s_maxlen);
+ }
+
return 0;
}
@@ -1641,7 +1660,7 @@ static int load_superblock(journal_t *journal)
* a journal, read the journal from disk to initialise the in-memory
* structures.
*/
-int jbd2_journal_load(journal_t *journal)
+int jbd2_journal_load(journal_t *journal, bool enable_fc)
{
int err;
journal_superblock_t *sb;
@@ -1684,6 +1703,12 @@ int jbd2_journal_load(journal_t *journal)
return -EFSCORRUPTED;
}
+ if (enable_fc)
+ jbd2_journal_set_features(journal, 0, 0,
+ JBD2_FEATURE_INCOMPAT_FAST_COMMIT);
+ else
+ jbd2_journal_clear_features(journal, 0, 0,
+ JBD2_FEATURE_INCOMPAT_FAST_COMMIT);
/* OK, we've finished with the dynamic journal bits:
* reinitialise the dynamic contents of the superblock in memory
* and reset them on disk. */
diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index 930e3d388579..3b4d91b16e8e 100644
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -1057,7 +1057,7 @@ int ocfs2_journal_load(struct ocfs2_journal *journal, int local, int replayed)
osb = journal->j_osb;
- status = jbd2_journal_load(journal->j_journal);
+ status = jbd2_journal_load(journal->j_journal, false);
if (status < 0) {
mlog(ML_ERROR, "Failed to load journal!\n");
goto done;
@@ -1642,7 +1642,7 @@ static int ocfs2_replay_journal(struct ocfs2_super *osb,
goto done;
}
- status = jbd2_journal_load(journal);
+ status = jbd2_journal_load(journal, false);
if (status < 0) {
mlog_errno(status);
if (!igrab(inode))
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 9a750b732241..153840b422cc 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1476,7 +1476,7 @@ extern int jbd2_journal_set_features
(journal_t *, unsigned long, unsigned long, unsigned long);
extern void jbd2_journal_clear_features
(journal_t *, unsigned long, unsigned long, unsigned long);
-extern int jbd2_journal_load (journal_t *journal);
+extern int jbd2_journal_load(journal_t *journal, bool enable_fc);
extern int jbd2_journal_destroy (journal_t *);
extern int jbd2_journal_recover (journal_t *journal);
extern int jbd2_journal_wipe (journal_t *, int);
--
2.23.0.rc1.153.gdeed80330f-goog
