ext4_journal: introduce checkpoint mechanism.

diff --git a/lwext4/ext4_journal.c b/lwext4/ext4_journal.c
index 95bbd5a3260d8c3e56120a4a75c27937637935ea..9e4e9dfb57ebf0a6701d93daefe1e1e94863f2b1 100644 (file)
--- a/lwext4/ext4_journal.c
+++ b/lwext4/ext4_journal.c
@@ -775,6 +775,7 @@ int jbd_journal_start(struct jbd_fs *jbd_fs,
        journal->start = journal->first;
        journal->last = journal->first;
        journal->trans_id = 1;
+       journal->alloc_trans_id = 1;
 
        journal->block_size = jbd_get32(&jbd_fs->sb, blocksize);
 
@@ -792,9 +793,11 @@ int jbd_journal_stop(struct jbd_journal *journal)
        return jbd_write_sb(journal->jbd_fs);
 }
 
-static uint32_t jbd_journal_alloc_block(struct jbd_journal *journal)
+static uint32_t jbd_journal_alloc_block(struct jbd_journal *journal,
+                                       struct jbd_trans *trans)
 {
        uint32_t start_block = journal->last++;
+       trans->alloc_blocks++;
        wrap(&journal->jbd_fs->sb, journal->last);
        return start_block;
 }
@@ -813,6 +816,11 @@ jbd_journal_new_trans(struct jbd_journal *journal)
        return trans;
 }
 
+static void jbd_trans_end_write(struct ext4_bcache *bc __unused,
+                         struct ext4_buf *buf __unused,
+                         int res,
+                         void *arg);
+
 int jbd_trans_add_block(struct jbd_trans *trans,
                        struct ext4_block *block)
 {
@@ -823,6 +831,10 @@ int jbd_trans_add_block(struct jbd_trans *trans,
        buf->trans = trans;
        buf->block = *block;
        ext4_bcache_inc_ref(block->buf);
+
+       block->buf->end_write = jbd_trans_end_write;
+       block->buf->end_write_arg = trans;
+
        trans->data_cnt++;
        LIST_INSERT_HEAD(&trans->buf_list, buf, buf_node);
        return EOK;
@@ -861,15 +873,6 @@ void jbd_journal_free_trans(struct jbd_journal *journal,
        free(trans);
 }
 
-static void jbd_trans_end_write(struct ext4_bcache *bc __unused,
-                         struct ext4_buf *buf __unused,
-                         int res,
-                         void *arg)
-{
-       struct jbd_trans *trans = arg;
-       trans->error = res;
-}
-
 static int jbd_trans_write_commit_block(struct jbd_trans *trans)
 {
        int rc;
@@ -878,7 +881,7 @@ static int jbd_trans_write_commit_block(struct jbd_trans *trans)
        struct ext4_block commit_block;
        struct jbd_journal *journal = trans->journal;
 
-       commit_iblock = jbd_journal_alloc_block(trans->journal);
+       commit_iblock = jbd_journal_alloc_block(journal, trans);
        rc = jbd_block_get_noread(journal->jbd_fs,
                        &commit_block, commit_iblock);
        if (rc != EOK)
@@ -914,7 +917,7 @@ static int jbd_journal_prepare(struct jbd_journal *journal,
 again:
                if (!desc_iblock) {
                        struct jbd_bhdr *bhdr;
-                       desc_iblock = jbd_journal_alloc_block(journal);
+                       desc_iblock = jbd_journal_alloc_block(journal, trans);
                        rc = jbd_block_get_noread(journal->jbd_fs,
                                           &desc_block, desc_iblock);
                        if (!rc)
@@ -952,7 +955,7 @@ again:
                        goto again;
                }
 
-               data_iblock = jbd_journal_alloc_block(journal);
+               data_iblock = jbd_journal_alloc_block(journal, trans);
                rc = jbd_block_get_noread(journal->jbd_fs,
                                &data_block, data_iblock);
                if (rc != EOK)
@@ -1000,7 +1003,7 @@ jbd_journal_prepare_revoke(struct jbd_journal *journal,
 again:
                if (!desc_iblock) {
                        struct jbd_bhdr *bhdr;
-                       desc_iblock = jbd_journal_alloc_block(journal);
+                       desc_iblock = jbd_journal_alloc_block(journal, trans);
                        rc = jbd_block_get_noread(journal->jbd_fs,
                                           &desc_block, desc_iblock);
                        if (!rc) {
@@ -1060,64 +1063,60 @@ jbd_journal_submit_trans(struct jbd_journal *journal,
                          trans_node);
 }
 
+static void jbd_trans_end_write(struct ext4_bcache *bc __unused,
+                         struct ext4_buf *buf __unused,
+                         int res,
+                         void *arg)
+{
+       struct jbd_trans *trans = arg;
+       struct jbd_journal *journal = trans->journal;
+       if (res != EOK)
+               trans->error = res;
+
+       trans->written_cnt++;
+       if (trans->written_cnt == trans->data_cnt) {
+               TAILQ_REMOVE(&journal->cp_queue, trans, trans_node);
+               journal->start += trans->alloc_blocks;
+               journal->trans_id = ++trans->trans_id;
+               jbd_journal_write_sb(journal);
+               jbd_journal_free_trans(journal, trans);
+       }
+}
+
 /*
  * XXX: one should disable cache writeback first.
  */
-void
-jbd_journal_commit_to_disk(struct jbd_journal *journal)
+static void
+jbd_journal_commit_one(struct jbd_journal *journal)
 {
-       int rc;
-       uint32_t last = journal->last,
-                trans_id = journal->trans_id,
-                start = journal->start;
-       struct jbd_trans *trans, *tmp;
-       TAILQ_FOREACH_SAFE(trans, &journal->trans_queue,
-                          trans_node,
-                          tmp) {
-               struct jbd_buf *jbd_buf;
+       int rc = EOK;
+       uint32_t last = journal->last;
+       struct jbd_trans *trans;
+       if ((trans = TAILQ_FIRST(&journal->trans_queue))) {
                TAILQ_REMOVE(&journal->trans_queue, trans, trans_node);
 
-               trans->trans_id = trans_id + 1;
+               trans->trans_id = journal->alloc_trans_id;
                rc = jbd_journal_prepare(journal, trans);
-               if (rc != EOK) {
-                       journal->last = last;
-                       jbd_journal_free_trans(journal, trans);
-                       continue;
-               }
+               if (rc != EOK)
+                       goto Finish;
+
                rc = jbd_journal_prepare_revoke(journal, trans);
-               if (rc != EOK) {
-                       journal->last = last;
-                       jbd_journal_free_trans(journal, trans);
-                       continue;
-               }
+               if (rc != EOK)
+                       goto Finish;
+
                rc = jbd_trans_write_commit_block(trans);
-               if (rc != EOK) {
-                       journal->last = last;
-                       jbd_journal_free_trans(journal, trans);
-                       continue;
-               }
-               LIST_FOREACH(jbd_buf, &trans->buf_list, buf_node) {
-                       struct ext4_block *block = &jbd_buf->block;
-                       block->buf->end_write = jbd_trans_end_write;
-                       block->buf->end_write_arg = trans;
-                       ext4_block_set(journal->jbd_fs->inode_ref.fs->bdev,
-                                       block);
-               }
-               if (trans->error != EOK) {
-                       journal->last = last;
-                       jbd_journal_free_trans(journal, trans);
-                       continue;
-               }
+               if (rc != EOK)
+                       goto Finish;
 
-               start = last;
-               trans_id++;
-               last = journal->last;
+               journal->alloc_trans_id++;
+               TAILQ_INSERT_TAIL(&journal->cp_queue, trans,
+                         trans_node);
+       }
+Finish:
+       if (rc != EOK) {
+               journal->last = last;
                jbd_journal_free_trans(journal, trans);
        }
-       
-       journal->start = start;
-       journal->trans_id = trans_id;
-       jbd_journal_write_sb(journal);
 }
 
 /**

diff --git a/lwext4/ext4_types.h b/lwext4/ext4_types.h
index 366474ea18ed4c89892e32f739470537c8ffc120..23a3e83d0e89d8383b30f23eda337c1117686b8a 100644 (file)
--- a/lwext4/ext4_types.h
+++ b/lwext4/ext4_types.h
@@ -1107,7 +1107,9 @@ struct jbd_revoke_rec {
 struct jbd_trans {
        uint32_t trans_id;
 
+       int alloc_blocks;
        int data_cnt;
+       int written_cnt;
        int error;
 
        struct jbd_journal *journal;
@@ -1122,10 +1124,12 @@ struct jbd_journal {
        uint32_t start;
        uint32_t last;
        uint32_t trans_id;
+       uint32_t alloc_trans_id;
 
        uint32_t block_size;
 
        TAILQ_HEAD(jbd_trans_queue, jbd_trans) trans_queue;
+       TAILQ_HEAD(jbd_cp_queue, jbd_trans) cp_queue;
 
        struct jbd_fs *jbd_fs;
 };