centos man page for journal_extend

JOURNAL_EXTEND(9)					     The Linux Journalling API						 JOURNAL_EXTEND(9)

NAME
       journal_extend - extend buffer credits.

SYNOPSIS
       int journal_extend(handle_t * handle, int nblocks);

ARGUMENTS
       handle
	   handle to 'extend'

       nblocks
	   nr blocks to try to extend by.

DESCRIPTION
       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.

AUTHORS
       Roger Gammans <rgammans@computer-surgery.co.uk>
	   Author.

       Stephen Tweedie <sct@redhat.com>
	   Author.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014							 JOURNAL_EXTEND(9)