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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.4 * All Rights Reserved.5 */6#include "xfs.h"7#include "xfs_fs.h"8#include "xfs_shared.h"9#include "xfs_format.h"10#include "xfs_log_format.h"11#include "xfs_trans_resv.h"12#include "xfs_sb.h"13#include "xfs_mount.h"14#include "xfs_trans.h"15#include "xfs_error.h"16#include "xfs_alloc.h"17#include "xfs_fsops.h"18#include "xfs_trans_space.h"19#include "xfs_log.h"20#include "xfs_log_priv.h"21#include "xfs_ag.h"22#include "xfs_ag_resv.h"23#include "xfs_trace.h"24 25/*26 * Write new AG headers to disk. Non-transactional, but need to be27 * written and completed prior to the growfs transaction being logged.28 * To do this, we use a delayed write buffer list and wait for29 * submission and IO completion of the list as a whole. This allows the30 * IO subsystem to merge all the AG headers in a single AG into a single31 * IO and hide most of the latency of the IO from us.32 *33 * This also means that if we get an error whilst building the buffer34 * list to write, we can cancel the entire list without having written35 * anything.36 */37static int38xfs_resizefs_init_new_ags(39	struct xfs_trans	*tp,40	struct aghdr_init_data	*id,41	xfs_agnumber_t		oagcount,42	xfs_agnumber_t		nagcount,43	xfs_rfsblock_t		delta,44	struct xfs_perag	*last_pag,45	bool			*lastag_extended)46{47	struct xfs_mount	*mp = tp->t_mountp;48	xfs_rfsblock_t		nb = mp->m_sb.sb_dblocks + delta;49	int			error;50 51	*lastag_extended = false;52 53	INIT_LIST_HEAD(&id->buffer_list);54	for (id->agno = nagcount - 1;55	     id->agno >= oagcount;56	     id->agno--, delta -= id->agsize) {57 58		if (id->agno == nagcount - 1)59			id->agsize = nb - (id->agno *60					(xfs_rfsblock_t)mp->m_sb.sb_agblocks);61		else62			id->agsize = mp->m_sb.sb_agblocks;63 64		error = xfs_ag_init_headers(mp, id);65		if (error) {66			xfs_buf_delwri_cancel(&id->buffer_list);67			return error;68		}69	}70 71	error = xfs_buf_delwri_submit(&id->buffer_list);72	if (error)73		return error;74 75	if (delta) {76		*lastag_extended = true;77		error = xfs_ag_extend_space(last_pag, tp, delta);78	}79	return error;80}81 82/*83 * growfs operations84 */85static int86xfs_growfs_data_private(87	struct xfs_mount	*mp,		/* mount point for filesystem */88	struct xfs_growfs_data	*in)		/* growfs data input struct */89{90	xfs_agnumber_t		oagcount = mp->m_sb.sb_agcount;91	struct xfs_buf		*bp;92	int			error;93	xfs_agnumber_t		nagcount;94	xfs_agnumber_t		nagimax = 0;95	xfs_rfsblock_t		nb, nb_div, nb_mod;96	int64_t			delta;97	bool			lastag_extended = false;98	struct xfs_trans	*tp;99	struct aghdr_init_data	id = {};100	struct xfs_perag	*last_pag;101 102	nb = in->newblocks;103	error = xfs_sb_validate_fsb_count(&mp->m_sb, nb);104	if (error)105		return error;106 107	if (nb > mp->m_sb.sb_dblocks) {108		error = xfs_buf_read_uncached(mp->m_ddev_targp,109				XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),110				XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL);111		if (error)112			return error;113		xfs_buf_relse(bp);114	}115 116	nb_div = nb;117	nb_mod = do_div(nb_div, mp->m_sb.sb_agblocks);118	if (nb_mod && nb_mod >= XFS_MIN_AG_BLOCKS)119		nb_div++;120	else if (nb_mod)121		nb = nb_div * mp->m_sb.sb_agblocks;122 123	if (nb_div > XFS_MAX_AGNUMBER + 1) {124		nb_div = XFS_MAX_AGNUMBER + 1;125		nb = nb_div * mp->m_sb.sb_agblocks;126	}127	nagcount = nb_div;128	delta = nb - mp->m_sb.sb_dblocks;129	/*130	 * Reject filesystems with a single AG because they are not131	 * supported, and reject a shrink operation that would cause a132	 * filesystem to become unsupported.133	 */134	if (delta < 0 && nagcount < 2)135		return -EINVAL;136 137	/* No work to do */138	if (delta == 0)139		return 0;140 141	/* TODO: shrinking the entire AGs hasn't yet completed */142	if (nagcount < oagcount)143		return -EINVAL;144 145	/* allocate the new per-ag structures */146	error = xfs_initialize_perag(mp, oagcount, nagcount, nb, &nagimax);147	if (error)148		return error;149 150	if (delta > 0)151		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata,152				XFS_GROWFS_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,153				&tp);154	else155		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata, -delta, 0,156				0, &tp);157	if (error)158		goto out_free_unused_perag;159 160	last_pag = xfs_perag_get(mp, oagcount - 1);161	if (delta > 0) {162		error = xfs_resizefs_init_new_ags(tp, &id, oagcount, nagcount,163				delta, last_pag, &lastag_extended);164	} else {165		xfs_warn_mount(mp, XFS_OPSTATE_WARNED_SHRINK,166	"EXPERIMENTAL online shrink feature in use. Use at your own risk!");167 168		error = xfs_ag_shrink_space(last_pag, &tp, -delta);169	}170	xfs_perag_put(last_pag);171	if (error)172		goto out_trans_cancel;173 174	/*175	 * Update changed superblock fields transactionally. These are not176	 * seen by the rest of the world until the transaction commit applies177	 * them atomically to the superblock.178	 */179	if (nagcount > oagcount)180		xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);181	if (delta)182		xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS, delta);183	if (id.nfree)184		xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, id.nfree);185 186	/*187	 * Sync sb counters now to reflect the updated values. This is188	 * particularly important for shrink because the write verifier189	 * will fail if sb_fdblocks is ever larger than sb_dblocks.190	 */191	if (xfs_has_lazysbcount(mp))192		xfs_log_sb(tp);193 194	xfs_trans_set_sync(tp);195	error = xfs_trans_commit(tp);196	if (error)197		return error;198 199	/* New allocation groups fully initialized, so update mount struct */200	if (nagimax)201		mp->m_maxagi = nagimax;202	xfs_set_low_space_thresholds(mp);203	mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);204 205	if (delta > 0) {206		/*207		 * If we expanded the last AG, free the per-AG reservation208		 * so we can reinitialize it with the new size.209		 */210		if (lastag_extended) {211			struct xfs_perag	*pag;212 213			pag = xfs_perag_get(mp, id.agno);214			xfs_ag_resv_free(pag);215			xfs_perag_put(pag);216		}217		/*218		 * Reserve AG metadata blocks. ENOSPC here does not mean there219		 * was a growfs failure, just that there still isn't space for220		 * new user data after the grow has been run.221		 */222		error = xfs_fs_reserve_ag_blocks(mp);223		if (error == -ENOSPC)224			error = 0;225	}226	return error;227 228out_trans_cancel:229	xfs_trans_cancel(tp);230out_free_unused_perag:231	if (nagcount > oagcount)232		xfs_free_perag_range(mp, oagcount, nagcount);233	return error;234}235 236static int237xfs_growfs_log_private(238	struct xfs_mount	*mp,	/* mount point for filesystem */239	struct xfs_growfs_log	*in)	/* growfs log input struct */240{241	xfs_extlen_t		nb;242 243	nb = in->newblocks;244	if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))245		return -EINVAL;246	if (nb == mp->m_sb.sb_logblocks &&247	    in->isint == (mp->m_sb.sb_logstart != 0))248		return -EINVAL;249	/*250	 * Moving the log is hard, need new interfaces to sync251	 * the log first, hold off all activity while moving it.252	 * Can have shorter or longer log in the same space,253	 * or transform internal to external log or vice versa.254	 */255	return -ENOSYS;256}257 258static int259xfs_growfs_imaxpct(260	struct xfs_mount	*mp,261	__u32			imaxpct)262{263	struct xfs_trans	*tp;264	int			dpct;265	int			error;266 267	if (imaxpct > 100)268		return -EINVAL;269 270	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata,271			XFS_GROWFS_SPACE_RES(mp), 0, XFS_TRANS_RESERVE, &tp);272	if (error)273		return error;274 275	dpct = imaxpct - mp->m_sb.sb_imax_pct;276	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);277	xfs_trans_set_sync(tp);278	return xfs_trans_commit(tp);279}280 281/*282 * protected versions of growfs function acquire and release locks on the mount283 * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,284 * XFS_IOC_FSGROWFSRT285 */286int287xfs_growfs_data(288	struct xfs_mount	*mp,289	struct xfs_growfs_data	*in)290{291	int			error = 0;292 293	if (!capable(CAP_SYS_ADMIN))294		return -EPERM;295	if (!mutex_trylock(&mp->m_growlock))296		return -EWOULDBLOCK;297 298	/* update imaxpct separately to the physical grow of the filesystem */299	if (in->imaxpct != mp->m_sb.sb_imax_pct) {300		error = xfs_growfs_imaxpct(mp, in->imaxpct);301		if (error)302			goto out_error;303	}304 305	if (in->newblocks != mp->m_sb.sb_dblocks) {306		error = xfs_growfs_data_private(mp, in);307		if (error)308			goto out_error;309	}310 311	/* Post growfs calculations needed to reflect new state in operations */312	if (mp->m_sb.sb_imax_pct) {313		uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;314		do_div(icount, 100);315		M_IGEO(mp)->maxicount = XFS_FSB_TO_INO(mp, icount);316	} else317		M_IGEO(mp)->maxicount = 0;318 319	/* Update secondary superblocks now the physical grow has completed */320	error = xfs_update_secondary_sbs(mp);321 322out_error:323	/*324	 * Increment the generation unconditionally, the error could be from325	 * updating the secondary superblocks, in which case the new size326	 * is live already.327	 */328	mp->m_generation++;329	mutex_unlock(&mp->m_growlock);330	return error;331}332 333int334xfs_growfs_log(335	xfs_mount_t		*mp,336	struct xfs_growfs_log	*in)337{338	int error;339 340	if (!capable(CAP_SYS_ADMIN))341		return -EPERM;342	if (!mutex_trylock(&mp->m_growlock))343		return -EWOULDBLOCK;344	error = xfs_growfs_log_private(mp, in);345	mutex_unlock(&mp->m_growlock);346	return error;347}348 349/*350 * Reserve the requested number of blocks if available. Otherwise return351 * as many as possible to satisfy the request. The actual number352 * reserved are returned in outval.353 */354int355xfs_reserve_blocks(356	struct xfs_mount	*mp,357	uint64_t		request)358{359	int64_t			lcounter, delta;360	int64_t			fdblks_delta = 0;361	int64_t			free;362	int			error = 0;363 364	/*365	 * With per-cpu counters, this becomes an interesting problem. we need366	 * to work out if we are freeing or allocation blocks first, then we can367	 * do the modification as necessary.368	 *369	 * We do this under the m_sb_lock so that if we are near ENOSPC, we will370	 * hold out any changes while we work out what to do. This means that371	 * the amount of free space can change while we do this, so we need to372	 * retry if we end up trying to reserve more space than is available.373	 */374	spin_lock(&mp->m_sb_lock);375 376	/*377	 * If our previous reservation was larger than the current value,378	 * then move any unused blocks back to the free pool. Modify the resblks379	 * counters directly since we shouldn't have any problems unreserving380	 * space.381	 */382	if (mp->m_resblks > request) {383		lcounter = mp->m_resblks_avail - request;384		if (lcounter > 0) {		/* release unused blocks */385			fdblks_delta = lcounter;386			mp->m_resblks_avail -= lcounter;387		}388		mp->m_resblks = request;389		if (fdblks_delta) {390			spin_unlock(&mp->m_sb_lock);391			xfs_add_fdblocks(mp, fdblks_delta);392			spin_lock(&mp->m_sb_lock);393		}394 395		goto out;396	}397 398	/*399	 * If the request is larger than the current reservation, reserve the400	 * blocks before we update the reserve counters. Sample m_fdblocks and401	 * perform a partial reservation if the request exceeds free space.402	 *403	 * The code below estimates how many blocks it can request from404	 * fdblocks to stash in the reserve pool.  This is a classic TOCTOU405	 * race since fdblocks updates are not always coordinated via406	 * m_sb_lock.  Set the reserve size even if there's not enough free407	 * space to fill it because mod_fdblocks will refill an undersized408	 * reserve when it can.409	 */410	free = percpu_counter_sum(&mp->m_fdblocks) -411						xfs_fdblocks_unavailable(mp);412	delta = request - mp->m_resblks;413	mp->m_resblks = request;414	if (delta > 0 && free > 0) {415		/*416		 * We'll either succeed in getting space from the free block417		 * count or we'll get an ENOSPC.  Don't set the reserved flag418		 * here - we don't want to reserve the extra reserve blocks419		 * from the reserve.420		 *421		 * The desired reserve size can change after we drop the lock.422		 * Use mod_fdblocks to put the space into the reserve or into423		 * fdblocks as appropriate.424		 */425		fdblks_delta = min(free, delta);426		spin_unlock(&mp->m_sb_lock);427		error = xfs_dec_fdblocks(mp, fdblks_delta, 0);428		if (!error)429			xfs_add_fdblocks(mp, fdblks_delta);430		spin_lock(&mp->m_sb_lock);431	}432out:433	spin_unlock(&mp->m_sb_lock);434	return error;435}436 437int438xfs_fs_goingdown(439	xfs_mount_t	*mp,440	uint32_t	inflags)441{442	switch (inflags) {443	case XFS_FSOP_GOING_FLAGS_DEFAULT: {444		if (!bdev_freeze(mp->m_super->s_bdev)) {445			xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);446			bdev_thaw(mp->m_super->s_bdev);447		}448		break;449	}450	case XFS_FSOP_GOING_FLAGS_LOGFLUSH:451		xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);452		break;453	case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:454		xfs_force_shutdown(mp,455				SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);456		break;457	default:458		return -EINVAL;459	}460 461	return 0;462}463 464/*465 * Force a shutdown of the filesystem instantly while keeping the filesystem466 * consistent. We don't do an unmount here; just shutdown the shop, make sure467 * that absolutely nothing persistent happens to this filesystem after this468 * point.469 *470 * The shutdown state change is atomic, resulting in the first and only the471 * first shutdown call processing the shutdown. This means we only shutdown the472 * log once as it requires, and we don't spam the logs when multiple concurrent473 * shutdowns race to set the shutdown flags.474 */475void476xfs_do_force_shutdown(477	struct xfs_mount *mp,478	uint32_t	flags,479	char		*fname,480	int		lnnum)481{482	int		tag;483	const char	*why;484 485 486	if (xfs_set_shutdown(mp)) {487		xlog_shutdown_wait(mp->m_log);488		return;489	}490	if (mp->m_sb_bp)491		mp->m_sb_bp->b_flags |= XBF_DONE;492 493	if (flags & SHUTDOWN_FORCE_UMOUNT)494		xfs_alert(mp, "User initiated shutdown received.");495 496	if (xlog_force_shutdown(mp->m_log, flags)) {497		tag = XFS_PTAG_SHUTDOWN_LOGERROR;498		why = "Log I/O Error";499	} else if (flags & SHUTDOWN_CORRUPT_INCORE) {500		tag = XFS_PTAG_SHUTDOWN_CORRUPT;501		why = "Corruption of in-memory data";502	} else if (flags & SHUTDOWN_CORRUPT_ONDISK) {503		tag = XFS_PTAG_SHUTDOWN_CORRUPT;504		why = "Corruption of on-disk metadata";505	} else if (flags & SHUTDOWN_DEVICE_REMOVED) {506		tag = XFS_PTAG_SHUTDOWN_IOERROR;507		why = "Block device removal";508	} else {509		tag = XFS_PTAG_SHUTDOWN_IOERROR;510		why = "Metadata I/O Error";511	}512 513	trace_xfs_force_shutdown(mp, tag, flags, fname, lnnum);514 515	xfs_alert_tag(mp, tag,516"%s (0x%x) detected at %pS (%s:%d).  Shutting down filesystem.",517			why, flags, __return_address, fname, lnnum);518	xfs_alert(mp,519		"Please unmount the filesystem and rectify the problem(s)");520	if (xfs_error_level >= XFS_ERRLEVEL_HIGH)521		xfs_stack_trace();522}523 524/*525 * Reserve free space for per-AG metadata.526 */527int528xfs_fs_reserve_ag_blocks(529	struct xfs_mount	*mp)530{531	xfs_agnumber_t		agno;532	struct xfs_perag	*pag;533	int			error = 0;534	int			err2;535 536	mp->m_finobt_nores = false;537	for_each_perag(mp, agno, pag) {538		err2 = xfs_ag_resv_init(pag, NULL);539		if (err2 && !error)540			error = err2;541	}542 543	if (error && error != -ENOSPC) {544		xfs_warn(mp,545	"Error %d reserving per-AG metadata reserve pool.", error);546		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);547	}548 549	return error;550}551 552/*553 * Free space reserved for per-AG metadata.554 */555void556xfs_fs_unreserve_ag_blocks(557	struct xfs_mount	*mp)558{559	xfs_agnumber_t		agno;560	struct xfs_perag	*pag;561 562	for_each_perag(mp, agno, pag)563		xfs_ag_resv_free(pag);564}565