This functions adds necessary APIs needed in JBD2 layer for fast
commits.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@xxxxxxxxx>
---
fs/ext4/fast_commit.c | 8 ++
fs/jbd2/commit.c | 44 ++++++++++
fs/jbd2/journal.c | 190 +++++++++++++++++++++++++++++++++++++++++-
include/linux/jbd2.h | 27 ++++++
4 files changed, 268 insertions(+), 1 deletion(-)
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index 0dad8bdb1253..f2d11b4c6b62 100644
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -8,11 +8,19 @@
* Ext4 fast commits routines.
*/
#include "ext4_jbd2.h"
+/*
+ * Fast commit cleanup routine. This is called after every fast commit and
+ * full commit. full is true if we are called after a full commit.
+ */
+static void ext4_fc_cleanup(journal_t *journal, int full)
+{
+}
void ext4_fc_init(struct super_block *sb, journal_t *journal)
{
if (!test_opt2(sb, JOURNAL_FAST_COMMIT))
return;
+ journal->j_fc_cleanup_callback = ext4_fc_cleanup;
if (jbd2_fc_init(journal, EXT4_NUM_FC_BLKS)) {
pr_warn("Error while enabling fast commits, turning off.");
ext4_clear_feature_fast_commit(sb);
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 6252b4c50666..fa688e163a80 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -206,6 +206,30 @@ int jbd2_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
return generic_writepages(mapping, &wbc);
}
+/* Send all the data buffers related to an inode */
+int jbd2_submit_inode_data(struct jbd2_inode *jinode)
+{
+
+ if (!jinode || !(jinode->i_flags & JI_WRITE_DATA))
+ return 0;
+
+ trace_jbd2_submit_inode_data(jinode->i_vfs_inode);
+ return jbd2_journal_submit_inode_data_buffers(jinode);
+
+}
+EXPORT_SYMBOL(jbd2_submit_inode_data);
+
+int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode)
+{
+ if (!jinode || !(jinode->i_flags & JI_WAIT_DATA) ||
+ !jinode->i_vfs_inode || !jinode->i_vfs_inode->i_mapping)
+ return 0;
+ return filemap_fdatawait_range_keep_errors(
+ jinode->i_vfs_inode->i_mapping, jinode->i_dirty_start,
+ jinode->i_dirty_end);
+}
+EXPORT_SYMBOL(jbd2_wait_inode_data);
+
/*
* Submit all the data buffers of inode associated with the transaction to
* disk.
@@ -415,6 +439,20 @@ void jbd2_journal_commit_transaction(journal_t *journal)
J_ASSERT(journal->j_running_transaction != NULL);
J_ASSERT(journal->j_committing_transaction == NULL);
+ write_lock(&journal->j_state_lock);
+ journal->j_flags |= JBD2_FULL_COMMIT_ONGOING;
+ while (journal->j_flags & JBD2_FAST_COMMIT_ONGOING) {
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait(&journal->j_fc_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+ write_unlock(&journal->j_state_lock);
+ schedule();
+ write_lock(&journal->j_state_lock);
+ finish_wait(&journal->j_fc_wait, &wait);
+ }
+ write_unlock(&journal->j_state_lock);
+
commit_transaction = journal->j_running_transaction;
trace_jbd2_start_commit(journal, commit_transaction);
@@ -422,6 +460,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
commit_transaction->t_tid);
write_lock(&journal->j_state_lock);
+ journal->j_fc_off = 0;
J_ASSERT(commit_transaction->t_state == T_RUNNING);
commit_transaction->t_state = T_LOCKED;
@@ -1121,12 +1160,16 @@ void jbd2_journal_commit_transaction(journal_t *journal)
if (journal->j_commit_callback)
journal->j_commit_callback(journal, commit_transaction);
+ if (journal->j_fc_cleanup_callback)
+ journal->j_fc_cleanup_callback(journal, 1);
trace_jbd2_end_commit(journal, commit_transaction);
jbd_debug(1, "JBD2: commit %d complete, head %d\n",
journal->j_commit_sequence, journal->j_tail_sequence);
write_lock(&journal->j_state_lock);
+ journal->j_flags &= ~JBD2_FULL_COMMIT_ONGOING;
+ journal->j_flags &= ~JBD2_FAST_COMMIT_ONGOING;
spin_lock(&journal->j_list_lock);
commit_transaction->t_state = T_FINISHED;
/* Check if the transaction can be dropped now that we are finished */
@@ -1138,6 +1181,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
spin_unlock(&journal->j_list_lock);
write_unlock(&journal->j_state_lock);
wake_up(&journal->j_wait_done_commit);
+ wake_up(&journal->j_fc_wait);
/*
* Calculate overall stats
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 4497bfbac527..0c7c42bd530f 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -159,7 +159,9 @@ static void commit_timeout(struct timer_list *t)
*
* 1) COMMIT: Every so often we need to commit the current state of the
* filesystem to disk. The journal thread is responsible for writing
- * all of the metadata buffers to disk.
+ * all of the metadata buffers to disk. If a fast commit is ongoing
+ * journal thread waits until it's done and then continues from
+ * there on.
*
* 2) CHECKPOINT: We cannot reuse a used section of the log file until all
* of the data in that part of the log has been rewritten elsewhere on
@@ -716,6 +718,75 @@ int jbd2_log_wait_commit(journal_t *journal, tid_t tid)
return err;
}
+/*
+ * Start a fast commit. If there's an ongoing fast or full commit wait for
+ * it to complete. Returns 0 if a new fast commit was started. Returns -EALREADY
+ * if a fast commit is not needed, either because there's an already a commit
+ * going on or this tid has already been committed. Returns -EINVAL if no jbd2
+ * commit has yet been performed.
+ */
+int jbd2_fc_begin_commit(journal_t *journal, tid_t tid)
+{
+ /*
+ * Fast commits only allowed if at least one full commit has
+ * been processed.
+ */
+ if (!journal->j_stats.ts_tid)
+ return -EINVAL;
+
+ if (tid <= journal->j_commit_sequence)
+ return -EALREADY;
+
+ write_lock(&journal->j_state_lock);
+ if (journal->j_flags & JBD2_FULL_COMMIT_ONGOING ||
+ (journal->j_flags & JBD2_FAST_COMMIT_ONGOING)) {
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait(&journal->j_fc_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+ write_unlock(&journal->j_state_lock);
+ schedule();
+ finish_wait(&journal->j_fc_wait, &wait);
+ return -EALREADY;
+ }
+ journal->j_flags |= JBD2_FAST_COMMIT_ONGOING;
+ write_unlock(&journal->j_state_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL(jbd2_fc_begin_commit);
+
+/*
+ * Stop a fast commit. If fallback is set, this function starts commit of
+ * TID tid before any other fast commit can start.
+ */
+static int __jbd2_fc_end_commit(journal_t *journal, tid_t tid, bool fallback)
+{
+ if (journal->j_fc_cleanup_callback)
+ journal->j_fc_cleanup_callback(journal, 0);
+ write_lock(&journal->j_state_lock);
+ journal->j_flags &= ~JBD2_FAST_COMMIT_ONGOING;
+ if (fallback)
+ journal->j_flags |= JBD2_FULL_COMMIT_ONGOING;
+ write_unlock(&journal->j_state_lock);
+ wake_up(&journal->j_fc_wait);
+ if (fallback)
+ return jbd2_complete_transaction(journal, tid);
+ return 0;
+}
+
+int jbd2_fc_end_commit(journal_t *journal)
+{
+ return __jbd2_fc_end_commit(journal, 0, 0);
+}
+EXPORT_SYMBOL(jbd2_fc_end_commit);
+
+int jbd2_fc_end_commit_fallback(journal_t *journal, tid_t tid)
+{
+ return __jbd2_fc_end_commit(journal, tid, 1);
+}
+EXPORT_SYMBOL(jbd2_fc_end_commit_fallback);
+
/* Return 1 when transaction with given tid has already committed. */
int jbd2_transaction_committed(journal_t *journal, tid_t tid)
{
@@ -784,6 +855,110 @@ int jbd2_journal_next_log_block(journal_t *journal, unsigned long long *retp)
return jbd2_journal_bmap(journal, blocknr, retp);
}
+/* Map one fast commit buffer for use by the file system */
+int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out)
+{
+ unsigned long long pblock;
+ unsigned long blocknr;
+ int ret = 0;
+ struct buffer_head *bh;
+ int fc_off;
+
+ *bh_out = NULL;
+ write_lock(&journal->j_state_lock);
+
+ if (journal->j_fc_off + journal->j_fc_first < journal->j_fc_last) {
+ fc_off = journal->j_fc_off;
+ blocknr = journal->j_fc_first + fc_off;
+ journal->j_fc_off++;
+ } else {
+ ret = -EINVAL;
+ }
+ write_unlock(&journal->j_state_lock);
+
+ if (ret)
+ return ret;
+
+ ret = jbd2_journal_bmap(journal, blocknr, &pblock);
+ if (ret)
+ return ret;
+
+ bh = __getblk(journal->j_dev, pblock, journal->j_blocksize);
+ if (!bh)
+ return -ENOMEM;
+
+ lock_buffer(bh);
+
+ clear_buffer_uptodate(bh);
+ set_buffer_dirty(bh);
+ unlock_buffer(bh);
+ journal->j_fc_wbuf[fc_off] = bh;
+
+ *bh_out = bh;
+
+ return 0;
+}
+EXPORT_SYMBOL(jbd2_fc_get_buf);
+
+/*
+ * Wait on fast commit buffers that were allocated by jbd2_fc_get_buf
+ * for completion.
+ */
+int jbd2_fc_wait_bufs(journal_t *journal, int num_blks)
+{
+ struct buffer_head *bh;
+ int i, j_fc_off;
+
+ read_lock(&journal->j_state_lock);
+ j_fc_off = journal->j_fc_off;
+ read_unlock(&journal->j_state_lock);
+
+ /*
+ * Wait in reverse order to minimize chances of us being woken up before
+ * all IOs have completed
+ */
+ for (i = j_fc_off - 1; i >= j_fc_off - num_blks; i--) {
+ bh = journal->j_fc_wbuf[i];
+ wait_on_buffer(bh);
+ put_bh(bh);
+ journal->j_fc_wbuf[i] = NULL;
+ if (unlikely(!buffer_uptodate(bh)))
+ return -EIO;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(jbd2_fc_wait_bufs);
+
+/*
+ * Wait on fast commit buffers that were allocated by jbd2_fc_get_buf
+ * for completion.
+ */
+int jbd2_fc_release_bufs(journal_t *journal)
+{
+ struct buffer_head *bh;
+ int i, j_fc_off;
+
+ read_lock(&journal->j_state_lock);
+ j_fc_off = journal->j_fc_off;
+ read_unlock(&journal->j_state_lock);
+
+ /*
+ * Wait in reverse order to minimize chances of us being woken up before
+ * all IOs have completed
+ */
+ for (i = j_fc_off - 1; i >= 0; i--) {
+ bh = journal->j_fc_wbuf[i];
+ if (!bh)
+ break;
+ put_bh(bh);
+ journal->j_fc_wbuf[i] = NULL;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(jbd2_fc_release_bufs);
+
/*
* Conversion of logical to physical block numbers for the journal
*
@@ -1142,6 +1317,7 @@ static journal_t *journal_init_common(struct block_device *bdev,
init_waitqueue_head(&journal->j_wait_commit);
init_waitqueue_head(&journal->j_wait_updates);
init_waitqueue_head(&journal->j_wait_reserved);
+ init_waitqueue_head(&journal->j_fc_wait);
mutex_init(&journal->j_abort_mutex);
mutex_init(&journal->j_barrier);
mutex_init(&journal->j_checkpoint_mutex);
@@ -1495,6 +1671,7 @@ int jbd2_journal_update_sb_log_tail(journal_t *journal, tid_t tail_tid,
static void jbd2_mark_journal_empty(journal_t *journal, int write_op)
{
journal_superblock_t *sb = journal->j_superblock;
+ bool had_fast_commit = false;
BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex));
lock_buffer(journal->j_sb_buffer);
@@ -1508,9 +1685,20 @@ static void jbd2_mark_journal_empty(journal_t *journal, int write_op)
sb->s_sequence = cpu_to_be32(journal->j_tail_sequence);
sb->s_start = cpu_to_be32(0);
+ if (jbd2_has_feature_fast_commit(journal)) {
+ /*
+ * When journal is clean, no need to commit fast commit flag and
+ * make file system incompatible with older kernels.
+ */
+ jbd2_clear_feature_fast_commit(journal);
+ had_fast_commit = true;
+ }
jbd2_write_superblock(journal, write_op);
+ if (had_fast_commit)
+ jbd2_set_feature_fast_commit(journal);
+
/* Log is no longer empty */
write_lock(&journal->j_state_lock);
journal->j_flags |= JBD2_FLUSHED;
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 008629b4d615..a009d9b9c620 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -861,6 +861,13 @@ struct journal_s
*/
wait_queue_head_t j_wait_reserved;
+ /**
+ * @j_fc_wait:
+ *
+ * Wait queue to wait for completion of async fast commits.
+ */
+ wait_queue_head_t j_fc_wait;
+
/**
* @j_checkpoint_mutex:
*
@@ -1232,6 +1239,15 @@ struct journal_s
*/
struct lockdep_map j_trans_commit_map;
#endif
+
+ /**
+ * @j_fc_cleanup_callback:
+ *
+ * Clean-up after fast commit or full commit. JBD2 calls this function
+ * after every commit operation.
+ */
+ void (*j_fc_cleanup_callback)(struct journal_s *journal, int);
+
};
#define jbd2_might_wait_for_commit(j) \
@@ -1316,6 +1332,8 @@ JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT)
#define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file
* data write error in ordered
* mode */
+#define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */
+#define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */
/*
* Function declarations for the journaling transaction and buffer
@@ -1574,6 +1592,15 @@ extern int jbd2_cleanup_journal_tail(journal_t *);
/* Fast commit related APIs */
int jbd2_fc_init(journal_t *journal, int num_fc_blks);
+int jbd2_fc_begin_commit(journal_t *journal, tid_t tid);
+int jbd2_fc_end_commit(journal_t *journal);
+int jbd2_fc_end_commit_fallback(journal_t *journal, tid_t tid);
+int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out);
+int jbd2_submit_inode_data(struct jbd2_inode *jinode);
+int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode);
+int jbd2_fc_wait_bufs(journal_t *journal, int num_blks);
+int jbd2_fc_release_bufs(journal_t *journal);
+
/*
* is_journal_abort
*
--
2.29.0.rc1.297.gfa9743e501-goog
