Extend buffer credits.
int journal_extend(handle_t * handle, int nblocks);
handle
handle to 'extend'
nblocks
nr blocks to try to extend by.
Some transactions, such as large extends and truncates, can be done atomically all at once or in several stages. The operation requests a credit for a number of buffer modications in advance, but can extend its credit if it needs more.
journal_extend tries to give the running handle more buffer credits. It does not guarantee that allocation - this is a best-effort only. The calling process MUST be able to deal cleanly with a failure to extend here.
Return 0 on success, non-zero on failure.
return code < 0 implies an error return code > 0 implies normal transaction-full status.