/**
- * int journal_restart() - restart a handle .
+ * int journal_restart() - restart a handle.
* @handle: handle to restart
* @nblocks: nr credits requested
*
jh->b_next_transaction == transaction)
goto done;
+ /*
+ * this is the first time this transaction is touching this buffer,
+ * reset the modified flag
+ */
+ jh->b_modified = 0;
+
/*
* If there is already a copy-out version of this buffer, then we don't
* need to make another one
if (!frozen_buffer) {
printk(KERN_EMERG
"%s: OOM for frozen_buffer\n",
- __FUNCTION__);
+ __func__);
JBUFFER_TRACE(jh, "oom!");
error = -ENOMEM;
jbd_lock_bh_state(bh);
if (jh->b_transaction == NULL) {
jh->b_transaction = transaction;
+
+ /* first access by this transaction */
+ jh->b_modified = 0;
+
JBUFFER_TRACE(jh, "file as BJ_Reserved");
__journal_file_buffer(jh, transaction, BJ_Reserved);
} else if (jh->b_transaction == journal->j_committing_transaction) {
+ /* first access by this transaction */
+ jh->b_modified = 0;
+
JBUFFER_TRACE(jh, "set next transaction");
jh->b_next_transaction = transaction;
}
}
/**
- * int journal_get_undo_access() - Notify intent to modify metadata with
- * non-rewindable consequences
+ * int journal_get_undo_access() - Notify intent to modify metadata with non-rewindable consequences
* @handle: transaction
* @bh: buffer to undo
* @credits: store the number of taken credits here (if not NULL)
committed_data = jbd_alloc(jh2bh(jh)->b_size, GFP_NOFS);
if (!committed_data) {
printk(KERN_EMERG "%s: No memory for committed data\n",
- __FUNCTION__);
+ __func__);
err = -ENOMEM;
goto out;
}
}
/**
- * int journal_dirty_data() - mark a buffer as containing dirty data which
- * needs to be flushed before we can commit the
- * current transaction.
+ * int journal_dirty_data() - mark a buffer as containing dirty data to be flushed
* @handle: transaction
* @bh: bufferhead to mark
*
+ * Description:
+ * Mark a buffer as containing dirty data which needs to be flushed before
+ * we can commit the current transaction.
+ *
* The buffer is placed on the transaction's data list and is marked as
* belonging to the transaction.
*
}
/**
- * int journal_dirty_metadata() - mark a buffer as containing dirty metadata
+ * int journal_dirty_metadata() - mark a buffer as containing dirty metadata
* @handle: transaction to add buffer to.
* @bh: buffer to mark
*
- * mark dirty metadata which needs to be journaled as part of the current
+ * Mark dirty metadata which needs to be journaled as part of the current
* transaction.
*
* The buffer is placed on the transaction's metadata list and is marked
struct journal_head *jh;
int drop_reserve = 0;
int err = 0;
+ int was_modified = 0;
BUFFER_TRACE(bh, "entry");
goto not_jbd;
}
+ /* keep track of wether or not this transaction modified us */
+ was_modified = jh->b_modified;
+
/*
* The buffer's going from the transaction, we must drop
* all references -bzzz
JBUFFER_TRACE(jh, "belongs to current transaction: unfile");
- drop_reserve = 1;
+ /*
+ * we only want to drop a reference if this transaction
+ * modified the buffer
+ */
+ if (was_modified)
+ drop_reserve = 1;
/*
* We are no longer going to journal this buffer.
if (jh->b_next_transaction) {
J_ASSERT(jh->b_next_transaction == transaction);
jh->b_next_transaction = NULL;
- drop_reserve = 1;
+
+ /*
+ * only drop a reference if this transaction modified
+ * the buffer
+ */
+ if (was_modified)
+ drop_reserve = 1;
}
}
return err;
}
-/**int journal_force_commit() - force any uncommitted transactions
+/**
+ * int journal_force_commit() - force any uncommitted transactions
* @journal: journal to force
*
* For synchronous operations: force any uncommitted transactions
}
/**
- * void journal_invalidatepage()
- * @journal: journal to use for flush...
+ * void journal_invalidatepage() - invalidate a journal page
+ * @journal: journal to use for flush
* @page: page to flush
* @offset: length of page to invalidate.
*
* Reap page buffers containing data after offset in page.
- *
*/
void journal_invalidatepage(journal_t *journal,
struct page *page,
jh->b_transaction = jh->b_next_transaction;
jh->b_next_transaction = NULL;
__journal_file_buffer(jh, jh->b_transaction,
- was_dirty ? BJ_Metadata : BJ_Reserved);
+ jh->b_modified ? BJ_Metadata : BJ_Reserved);
J_ASSERT_JH(jh, jh->b_transaction->t_state == T_RUNNING);
if (was_dirty)