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#
# This list is used by git-shortlog to fix a few botched name translations
# in the git archive, either because the author's full name was messed up
# and/or not always written the same way, making contributions from the
# same person appearing not to be so or badly displayed.
#
# repo-abbrev: /pub/scm/linux/kernel/git/
#

Aaron Durbin <adurbin@google.com>
Adam Oldham <oldhamca@gmail.com>
Adam Radford <aradford@gmail.com>
Adrian Bunk <bunk@stusta.de>
Adriana Reus <adi.reus@gmail.com> <adriana.reus@intel.com>
Alan Cox <alan@lxorguk.ukuu.org.uk>
Alan Cox <root@hraefn.swansea.linux.org.uk>
Aleksey Gorelov <aleksey_gorelov@phoenix.com>
Aleksandar Markovic <aleksandar.markovic@mips.com> <aleksandar.markovic@imgtec.com>
Al Viro <viro@ftp.linux.org.uk>
Al Viro <viro@zenIV.linux.org.uk>
Andreas Herrmann <aherrman@de.ibm.com>
Andrey Ryabinin <ryabinin.a.a@gmail.com> <a.ryabinin@samsung.com>
Andrew Morton <akpm@linux-foundation.org>
Andrew Vasquez <andrew.vasquez@qlogic.com>
Andy Adamson <andros@citi.umich.edu>
Antoine Tenart <antoine.tenart@free-electrons.com>
Antonio Ospite <ao2@ao2.it> <ao2@amarulasolutions.com>
Archit Taneja <archit@ti.com>
Arnaud Patard <arnaud.patard@rtp-net.org>
Arnd Bergmann <arnd@arndb.de>
Axel Dyks <xl@xlsigned.net>
Axel Lin <axel.lin@gmail.com>
Ben Gardner <bgardner@wabtec.com>
Ben M Cahill <ben.m.cahill@intel.com>
Björn Steinbrink <B.Steinbrink@gmx.de>
Boris Brezillon <boris.brezillon@free-electrons.com>
Boris Brezillon <boris.brezillon@free-electrons.com> <b.brezillon.dev@gmail.com>
Boris Brezillon <boris.brezillon@free-electrons.com> <b.brezillon@overkiz.com>
Brian Avery <b.avery@hp.com>
Brian King <brking@us.ibm.com>
Christoph Hellwig <hch@lst.de>
Christophe Ricard <christophe.ricard@gmail.com>
Corey Minyard <minyard@acm.org>
Damian Hobson-Garcia <dhobsong@igel.co.jp>
David Brownell <david-b@pacbell.net>
David Woodhouse <dwmw2@shinybook.infradead.org>
Deng-Cheng Zhu <dengcheng.zhu@mips.com> <dengcheng.zhu@imgtec.com>
Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Domen Puncer <domen@coderock.org>
Douglas Gilbert <dougg@torque.net>
Ed L. Cashin <ecashin@coraid.com>
Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Felipe W Damasio <felipewd@terra.com.br>
Felix Kuhling <fxkuehl@gmx.de>
Felix Moeller <felix@derklecks.de>
Filipe Lautert <filipe@icewall.org>
Franck Bui-Huu <vagabon.xyz@gmail.com>
Frank Rowand <frowand.list@gmail.com> <frowand@mvista.com>
Frank Rowand <frowand.list@gmail.com> <frank.rowand@am.sony.com>
Frank Rowand <frowand.list@gmail.com> <frank.rowand@sonymobile.com>
Frank Zago <fzago@systemfabricworks.com>
Greg Kroah-Hartman <greg@echidna.(none)>
Greg Kroah-Hartman <gregkh@suse.de>
Greg Kroah-Hartman <greg@kroah.com>
Henk Vergonet <Henk.Vergonet@gmail.com>
Henrik Kretzschmar <henne@nachtwindheim.de>
Henrik Rydberg <rydberg@bitmath.org>
Herbert Xu <herbert@gondor.apana.org.au>
Jacob Shin <Jacob.Shin@amd.com>
James Bottomley <jejb@mulgrave.(none)>
James Bottomley <jejb@titanic.il.steeleye.com>
James E Wilson <wilson@specifix.com>
James Hogan <jhogan@kernel.org> <james.hogan@imgtec.com>
James Hogan <jhogan@kernel.org> <james@albanarts.com>
James Ketrenos <jketreno@io.(none)>
Jason Gunthorpe <jgg@ziepe.ca> <jgg@mellanox.com>
Jason Gunthorpe <jgg@ziepe.ca> <jgunthorpe@obsidianresearch.com>
Javi Merino <javi.merino@kernel.org> <javi.merino@arm.com>
<javier@osg.samsung.com> <javier.martinez@collabora.co.uk>
Jean Tourrilhes <jt@hpl.hp.com>
Jeff Garzik <jgarzik@pretzel.yyz.us>
Jens Axboe <axboe@suse.de>
Jens Osterkamp <Jens.Osterkamp@de.ibm.com>
Johan Hovold <johan@kernel.org> <jhovold@gmail.com>
Johan Hovold <johan@kernel.org> <johan@hovoldconsulting.com>
John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
John Stultz <johnstul@us.ibm.com>
<josh@joshtriplett.org> <josh@freedesktop.org>
<josh@joshtriplett.org> <josh@kernel.org>
<josh@joshtriplett.org> <josht@linux.vnet.ibm.com>
<josh@joshtriplett.org> <josht@us.ibm.com>
<josh@joshtriplett.org> <josht@vnet.ibm.com>
Juha Yrjola <at solidboot.com>
Juha Yrjola <juha.yrjola@nokia.com>
Juha Yrjola <juha.yrjola@solidboot.com>
Kay Sievers <kay.sievers@vrfy.org>
Kenneth W Chen <kenneth.w.chen@intel.com>
Konstantin Khlebnikov <koct9i@gmail.com> <k.khlebnikov@samsung.com>
Koushik <raghavendra.koushik@neterion.com>
Krzysztof Kozlowski <krzk@kernel.org> <k.kozlowski@samsung.com>
Krzysztof Kozlowski <krzk@kernel.org> <k.kozlowski.k@gmail.com>
Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Leonid I Ananiev <leonid.i.ananiev@intel.com>
Linas Vepstas <linas@austin.ibm.com>
Linus Lüssing <linus.luessing@c0d3.blue> <linus.luessing@web.de>
Linus Lüssing <linus.luessing@c0d3.blue> <linus.luessing@ascom.ch>
Maciej W. Rozycki <macro@mips.com> <macro@imgtec.com>
Marcin Nowakowski <marcin.nowakowski@mips.com> <marcin.nowakowski@imgtec.com>
Mark Brown <broonie@sirena.org.uk>
Mark Yao <markyao0591@gmail.com> <mark.yao@rock-chips.com>
Martin Kepplinger <martink@posteo.de> <martin.kepplinger@theobroma-systems.com>
Martin Kepplinger <martink@posteo.de> <martin.kepplinger@ginzinger.com>
Matthieu CASTET <castet.matthieu@free.fr>
Mauro Carvalho Chehab <mchehab@kernel.org> <mchehab@brturbo.com.br>
Mauro Carvalho Chehab <mchehab@kernel.org> <maurochehab@gmail.com>
Mauro Carvalho Chehab <mchehab@kernel.org> <mchehab@infradead.org>
Mauro Carvalho Chehab <mchehab@kernel.org> <mchehab@redhat.com>
Mauro Carvalho Chehab <mchehab@kernel.org> <m.chehab@samsung.com>
Mauro Carvalho Chehab <mchehab@kernel.org> <mchehab@osg.samsung.com>
Mauro Carvalho Chehab <mchehab@kernel.org> <mchehab@s-opensource.com>
Matt Ranostay <mranostay@gmail.com> Matthew Ranostay <mranostay@embeddedalley.com>
Matt Ranostay <mranostay@gmail.com> <matt.ranostay@intel.com>
Matt Ranostay <matt.ranostay@konsulko.com> <matt@ranostay.consulting>
Matt Redfearn <matt.redfearn@mips.com> <matt.redfearn@imgtec.com>
Mayuresh Janorkar <mayur@ti.com>
Michael Buesch <m@bues.ch>
Michel Dänzer <michel@tungstengraphics.com>
Miodrag Dinic <miodrag.dinic@mips.com> <miodrag.dinic@imgtec.com>
Mitesh shah <mshah@teja.com>
Mohit Kumar <mohit.kumar@st.com> <mohit.kumar.dhaka@gmail.com>
Morten Welinder <terra@gnome.org>
Morten Welinder <welinder@anemone.rentec.com>
Morten Welinder <welinder@darter.rentec.com>
Morten Welinder <welinder@troll.com>
Mythri P K <mythripk@ti.com>
Nguyen Anh Quynh <aquynh@gmail.com>
Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Patrick Mochel <mochel@digitalimplant.org>
Paul Burton <paul.burton@mips.com> <paul.burton@imgtec.com>
Peter A Jonsson <pj@ludd.ltu.se>
Peter Oruba <peter@oruba.de>
Peter Oruba <peter.oruba@amd.com>
Pratyush Anand <pratyush.anand@gmail.com> <pratyush.anand@st.com>
Praveen BP <praveenbp@ti.com>
Qais Yousef <qsyousef@gmail.com> <qais.yousef@imgtec.com>
Rajesh Shah <rajesh.shah@intel.com>
Ralf Baechle <ralf@linux-mips.org>
Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
Randy Dunlap <rdunlap@infradead.org> <rdunlap@xenotime.net>
Rémi Denis-Courmont <rdenis@simphalempin.com>
Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Rudolf Marek <R.Marek@sh.cvut.cz>
Rui Saraiva <rmps@joel.ist.utl.pt>
Sachin P Sant <ssant@in.ibm.com>
Sarangdhar Joshi <spjoshi@codeaurora.org>
Sam Ravnborg <sam@mars.ravnborg.org>
Santosh Shilimkar <ssantosh@kernel.org>
Santosh Shilimkar <santosh.shilimkar@oracle.org>
Sascha Hauer <s.hauer@pengutronix.de>
S.Çağlar Onur <caglar@pardus.org.tr>
Sebastian Reichel <sre@kernel.org> <sre@debian.org>
Sebastian Reichel <sre@kernel.org> <sebastian.reichel@collabora.co.uk>
Shiraz Hashim <shiraz.linux.kernel@gmail.com> <shiraz.hashim@st.com>
Shuah Khan <shuah@kernel.org> <shuahkhan@gmail.com>
Shuah Khan <shuah@kernel.org> <shuah.khan@hp.com>
Shuah Khan <shuah@kernel.org> <shuahkh@osg.samsung.com>
Shuah Khan <shuah@kernel.org> <shuah.kh@samsung.com>
Simon Kelley <simon@thekelleys.org.uk>
Stéphane Witzmann <stephane.witzmann@ubpmes.univ-bpclermont.fr>
Stephen Hemminger <shemminger@osdl.org>
Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Subhash Jadavani <subhashj@codeaurora.org>
Sudeep Holla <sudeep.holla@arm.com> Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Sumit Semwal <sumit.semwal@ti.com>
Tejun Heo <htejun@gmail.com>
Thomas Graf <tgraf@suug.ch>
Thomas Pedersen <twp@codeaurora.org>
Tony Luck <tony.luck@intel.com>
Tsuneo Yoshioka <Tsuneo.Yoshioka@f-secure.com>
Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Uwe Kleine-König <ukl@pengutronix.de>
Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Viresh Kumar <vireshk@kernel.org> <viresh.kumar@st.com>
Viresh Kumar <vireshk@kernel.org> <viresh.linux@gmail.com>
Viresh Kumar <vireshk@kernel.org> <viresh.kumar2@arm.com>
Vlad Dogaru <ddvlad@gmail.com> <vlad.dogaru@intel.com>
Vladimir Davydov <vdavydov.dev@gmail.com> <vdavydov@virtuozzo.com>
Vladimir Davydov <vdavydov.dev@gmail.com> <vdavydov@parallels.com>
Takashi YOSHII <takashi.yoshii.zj@renesas.com>
Yakir Yang <kuankuan.y@gmail.com> <ykk@rock-chips.com>
Yusuke Goda <goda.yusuke@renesas.com>
Gustavo Padovan <gustavo@las.ic.unicamp.br>
Gustavo Padovan <padovan@profusion.mobi>
/*
 * This file is part of UBIFS.
 *
 * Copyright (C) 2006-2008 Nokia Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * Authors: Adrian Hunter
 *          Artem Bityutskiy (Битюцкий Артём)
 */

/*
 * This file implements the budgeting sub-system which is responsible for UBIFS
 * space management.
 *
 * Factors such as compression, wasted space at the ends of LEBs, space in other
 * journal heads, the effect of updates on the index, and so on, make it
 * impossible to accurately predict the amount of space needed. Consequently
 * approximations are used.
 */

#include "ubifs.h"
#include <linux/writeback.h>
#include <linux/math64.h>

/*
 * When pessimistic budget calculations say that there is no enough space,
 * UBIFS starts writing back dirty inodes and pages, doing garbage collection,
 * or committing. The below constant defines maximum number of times UBIFS
 * repeats the operations.
 */
#define MAX_MKSPC_RETRIES 3

/*
 * The below constant defines amount of dirty pages which should be written
 * back at when trying to shrink the liability.
 */
#define NR_TO_WRITE 16

/**
 * shrink_liability - write-back some dirty pages/inodes.
 * @c: UBIFS file-system description object
 * @nr_to_write: how many dirty pages to write-back
 *
 * This function shrinks UBIFS liability by means of writing back some amount
 * of dirty inodes and their pages.
 *
 * Note, this function synchronizes even VFS inodes which are locked
 * (@i_mutex) by the caller of the budgeting function, because write-back does
 * not touch @i_mutex.
 */
static void shrink_liability(struct ubifs_info *c, int nr_to_write)
{
	down_read(&c->vfs_sb->s_umount);
	writeback_inodes_sb(c->vfs_sb, WB_REASON_FS_FREE_SPACE);
	up_read(&c->vfs_sb->s_umount);
}

/**
 * run_gc - run garbage collector.
 * @c: UBIFS file-system description object
 *
 * This function runs garbage collector to make some more free space. Returns
 * zero if a free LEB has been produced, %-EAGAIN if commit is required, and a
 * negative error code in case of failure.
 */
static int run_gc(struct ubifs_info *c)
{
	int err, lnum;

	/* Make some free space by garbage-collecting dirty space */
	down_read(&c->commit_sem);
	lnum = ubifs_garbage_collect(c, 1);
	up_read(&c->commit_sem);
	if (lnum < 0)
		return lnum;

	/* GC freed one LEB, return it to lprops */
	dbg_budg("GC freed LEB %d", lnum);
	err = ubifs_return_leb(c, lnum);
	if (err)
		return err;
	return 0;
}

/**
 * get_liability - calculate current liability.
 * @c: UBIFS file-system description object
 *
 * This function calculates and returns current UBIFS liability, i.e. the
 * amount of bytes UBIFS has "promised" to write to the media.
 */
static long long get_liability(struct ubifs_info *c)
{
	long long liab;

	spin_lock(&c->space_lock);
	liab = c->bi.idx_growth + c->bi.data_growth + c->bi.dd_growth;
	spin_unlock(&c->space_lock);
	return liab;
}

/**
 * make_free_space - make more free space on the file-system.
 * @c: UBIFS file-system description object
 *
 * This function is called when an operation cannot be budgeted because there
 * is supposedly no free space. But in most cases there is some free space:
 *   o budgeting is pessimistic, so it always budgets more than it is actually
 *     needed, so shrinking the liability is one way to make free space - the
 *     cached data will take less space then it was budgeted for;
 *   o GC may turn some dark space into free space (budgeting treats dark space
 *     as not available);
 *   o commit may free some LEB, i.e., turn freeable LEBs into free LEBs.
 *
 * So this function tries to do the above. Returns %-EAGAIN if some free space
 * was presumably made and the caller has to re-try budgeting the operation.
 * Returns %-ENOSPC if it couldn't do more free space, and other negative error
 * codes on failures.
 */
static int make_free_space(struct ubifs_info *c)
{
	int err, retries = 0;
	long long liab1, liab2;

	do {
		liab1 = get_liability(c);
		/*
		 * We probably have some dirty pages or inodes (liability), try
		 * to write them back.
		 */
		dbg_budg("liability %lld, run write-back", liab1);
		shrink_liability(c, NR_TO_WRITE);

		liab2 = get_liability(c);
		if (liab2 < liab1)
			return -EAGAIN;

		dbg_budg("new liability %lld (not shrunk)", liab2);

		/* Liability did not shrink again, try GC */
		dbg_budg("Run GC");
		err = run_gc(c);
		if (!err)
			return -EAGAIN;

		if (err != -EAGAIN && err != -ENOSPC)
			/* Some real error happened */
			return err;

		dbg_budg("Run commit (retries %d)", retries);
		err = ubifs_run_commit(c);
		if (err)
			return err;
	} while (retries++ < MAX_MKSPC_RETRIES);

	return -ENOSPC;
}

/**
 * ubifs_calc_min_idx_lebs - calculate amount of LEBs for the index.
 * @c: UBIFS file-system description object
 *
 * This function calculates and returns the number of LEBs which should be kept
 * for index usage.
 */
int ubifs_calc_min_idx_lebs(struct ubifs_info *c)
{
	int idx_lebs;
	long long idx_size;

	idx_size = c->bi.old_idx_sz + c->bi.idx_growth + c->bi.uncommitted_idx;
	/* And make sure we have thrice the index size of space reserved */
	idx_size += idx_size << 1;
	/*
	 * We do not maintain 'old_idx_size' as 'old_idx_lebs'/'old_idx_bytes'
	 * pair, nor similarly the two variables for the new index size, so we
	 * have to do this costly 64-bit division on fast-path.
	 */
	idx_lebs = div_u64(idx_size + c->idx_leb_size - 1, c->idx_leb_size);
	/*
	 * The index head is not available for the in-the-gaps method, so add an
	 * extra LEB to compensate.
	 */
	idx_lebs += 1;
	if (idx_lebs < MIN_INDEX_LEBS)
		idx_lebs = MIN_INDEX_LEBS;
	return idx_lebs;
}

/**
 * ubifs_calc_available - calculate available FS space.
 * @c: UBIFS file-system description object
 * @min_idx_lebs: minimum number of LEBs reserved for the index
 *
 * This function calculates and returns amount of FS space available for use.
 */
long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs)
{
	int subtract_lebs;
	long long available;

	available = c->main_bytes - c->lst.total_used;

	/*
	 * Now 'available' contains theoretically available flash space
	 * assuming there is no index, so we have to subtract the space which
	 * is reserved for the index.
	 */
	subtract_lebs = min_idx_lebs;

	/* Take into account that GC reserves one LEB for its own needs */
	subtract_lebs += 1;

	/*
	 * The GC journal head LEB is not really accessible. And since
	 * different write types go to different heads, we may count only on
	 * one head's space.
	 */
	subtract_lebs += c->jhead_cnt - 1;

	/* We also reserve one LEB for deletions, which bypass budgeting */
	subtract_lebs += 1;

	available -= (long long)subtract_lebs * c->leb_size;

	/* Subtract the dead space which is not available for use */
	available -= c->lst.total_dead;

	/*
	 * Subtract dark space, which might or might not be usable - it depends
	 * on the data which we have on the media and which will be written. If
	 * this is a lot of uncompressed or not-compressible data, the dark
	 * space cannot be used.
	 */
	available -= c->lst.total_dark;

	/*
	 * However, there is more dark space. The index may be bigger than
	 * @min_idx_lebs. Those extra LEBs are assumed to be available, but
	 * their dark space is not included in total_dark, so it is subtracted
	 * here.
	 */
	if (c->lst.idx_lebs > min_idx_lebs) {
		subtract_lebs = c->lst.idx_lebs - min_idx_lebs;
		available -= subtract_lebs * c->dark_wm;
	}

	/* The calculations are rough and may end up with a negative number */
	return available > 0 ? available : 0;
}

/**
 * can_use_rp - check whether the user is allowed to use reserved pool.
 * @c: UBIFS file-system description object
 *
 * UBIFS has so-called "reserved pool" which is flash space reserved
 * for the superuser and for uses whose UID/GID is recorded in UBIFS superblock.
 * This function checks whether current user is allowed to use reserved pool.
 * Returns %1  current user is allowed to use reserved pool and %0 otherwise.
 */
static int can_use_rp(struct ubifs_info *c)
{
	if (uid_eq(current_fsuid(), c->rp_uid) || capable(CAP_SYS_RESOURCE) ||
	    (!gid_eq(c->rp_gid, GLOBAL_ROOT_GID) && in_group_p(c->rp_gid)))
		return 1;
	return 0;
}

/**
 * do_budget_space - reserve flash space for index and data growth.
 * @c: UBIFS file-system description object
 *
 * This function makes sure UBIFS has enough free LEBs for index growth and
 * data.
 *
 * When budgeting index space, UBIFS reserves thrice as many LEBs as the index
 * would take if it was consolidated and written to the flash. This guarantees
 * that the "in-the-gaps" commit method always succeeds and UBIFS will always
 * be able to commit dirty index. So this function basically adds amount of
 * budgeted index space to the size of the current index, multiplies this by 3,
 * and makes sure this does not exceed the amount of free LEBs.
 *
 * Notes about @c->bi.min_idx_lebs and @c->lst.idx_lebs variables:
 * o @c->lst.idx_lebs is the number of LEBs the index currently uses. It might
 *    be large, because UBIFS does not do any index consolidation as long as
 *    there is free space. IOW, the index may take a lot of LEBs, but the LEBs
 *    will contain a lot of dirt.
 * o @c->bi.min_idx_lebs is the number of LEBS the index presumably takes. IOW,
 *    the index may be consolidated to take up to @c->bi.min_idx_lebs LEBs.
 *
 * This function returns zero in case of success, and %-ENOSPC in case of
 * failure.
 */
static int do_budget_space(struct ubifs_info *c)
{
	long long outstanding, available;
	int lebs, rsvd_idx_lebs, min_idx_lebs;

	/* First budget index space */
	min_idx_lebs = ubifs_calc_min_idx_lebs(c);

	/* Now 'min_idx_lebs' contains number of LEBs to reserve */
	if (min_idx_lebs > c->lst.idx_lebs)
		rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs;
	else
		rsvd_idx_lebs = 0;

	/*
	 * The number of LEBs that are available to be used by the index is:
	 *
	 *    @c->lst.empty_lebs + @c->freeable_cnt + @c->idx_gc_cnt -
	 *    @c->lst.taken_empty_lebs
	 *
	 * @c->lst.empty_lebs are available because they are empty.
	 * @c->freeable_cnt are available because they contain only free and
	 * dirty space, @c->idx_gc_cnt are available because they are index
	 * LEBs that have been garbage collected and are awaiting the commit
	 * before they can be used. And the in-the-gaps method will grab these
	 * if it needs them. @c->lst.taken_empty_lebs are empty LEBs that have
	 * already been allocated for some purpose.
	 *
	 * Note, @c->idx_gc_cnt is included to both @c->lst.empty_lebs (because
	 * these LEBs are empty) and to @c->lst.taken_empty_lebs (because they
	 * are taken until after the commit).
	 *
	 * Note, @c->lst.taken_empty_lebs may temporarily be higher by one
	 * because of the way we serialize LEB allocations and budgeting. See a
	 * comment in 'ubifs_find_free_space()'.
	 */
	lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
	       c->lst.taken_empty_lebs;
	if (unlikely(rsvd_idx_lebs > lebs)) {
		dbg_budg("out of indexing space: min_idx_lebs %d (old %d), rsvd_idx_lebs %d",
			 min_idx_lebs, c->bi.min_idx_lebs, rsvd_idx_lebs);
		return -ENOSPC;
	}

	available = ubifs_calc_available(c, min_idx_lebs);
	outstanding = c->bi.data_growth + c->bi.dd_growth;

	if (unlikely(available < outstanding)) {
		dbg_budg("out of data space: available %lld, outstanding %lld",
			 available, outstanding);
		return -ENOSPC;
	}

	if (available - outstanding <= c->rp_size && !can_use_rp(c))
		return -ENOSPC;

	c->bi.min_idx_lebs = min_idx_lebs;
	return 0;
}

/**
 * calc_idx_growth - calculate approximate index growth from budgeting request.
 * @c: UBIFS file-system description object