write_out_data in JBD

[Zoltan Menyhart <Zoltan.Menyhart@bull.net>]

Stephen,

Here is a code fragment starting at "write_out_data:" in
"journal_commit_transaction()":

Let's assume that there is a single "jh" on the list.

write_out_data:
   while (commit_transaction->t_sync_datalist) {

       jh = commit_transaction->t_sync_datalist;
       commit_transaction->t_sync_datalist = jh->b_tnext;

       // "commit_transaction->t_sync_datalist" happens always
       // to point at our single "jh"

       bh = jh2bh(jh);

       // Assume not locked
       // Assume dirty

       if (buffer_dirty(bh)) {
           get_bh(bh);
           wbuf[bufs++] = bh;
           if (bufs == journal->j_wbufsize) {
               ...
               goto write_out_data;
           }
       } else ...
   }

I think our single "jh" will be put on "wbuf[]" repeatedly
("journal->j_wbufsize" times).

Regards,

Zoltan Menyhart