cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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xfs_bmap_item.c (18911B)


      1// SPDX-License-Identifier: GPL-2.0+
      2/*
      3 * Copyright (C) 2016 Oracle.  All Rights Reserved.
      4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
      5 */
      6#include "xfs.h"
      7#include "xfs_fs.h"
      8#include "xfs_format.h"
      9#include "xfs_log_format.h"
     10#include "xfs_trans_resv.h"
     11#include "xfs_bit.h"
     12#include "xfs_shared.h"
     13#include "xfs_mount.h"
     14#include "xfs_defer.h"
     15#include "xfs_inode.h"
     16#include "xfs_trans.h"
     17#include "xfs_trans_priv.h"
     18#include "xfs_bmap_item.h"
     19#include "xfs_log.h"
     20#include "xfs_bmap.h"
     21#include "xfs_icache.h"
     22#include "xfs_bmap_btree.h"
     23#include "xfs_trans_space.h"
     24#include "xfs_error.h"
     25#include "xfs_log_priv.h"
     26#include "xfs_log_recover.h"
     27
     28struct kmem_cache	*xfs_bui_cache;
     29struct kmem_cache	*xfs_bud_cache;
     30
     31static const struct xfs_item_ops xfs_bui_item_ops;
     32
     33static inline struct xfs_bui_log_item *BUI_ITEM(struct xfs_log_item *lip)
     34{
     35	return container_of(lip, struct xfs_bui_log_item, bui_item);
     36}
     37
     38STATIC void
     39xfs_bui_item_free(
     40	struct xfs_bui_log_item	*buip)
     41{
     42	kmem_free(buip->bui_item.li_lv_shadow);
     43	kmem_cache_free(xfs_bui_cache, buip);
     44}
     45
     46/*
     47 * Freeing the BUI requires that we remove it from the AIL if it has already
     48 * been placed there. However, the BUI may not yet have been placed in the AIL
     49 * when called by xfs_bui_release() from BUD processing due to the ordering of
     50 * committed vs unpin operations in bulk insert operations. Hence the reference
     51 * count to ensure only the last caller frees the BUI.
     52 */
     53STATIC void
     54xfs_bui_release(
     55	struct xfs_bui_log_item	*buip)
     56{
     57	ASSERT(atomic_read(&buip->bui_refcount) > 0);
     58	if (!atomic_dec_and_test(&buip->bui_refcount))
     59		return;
     60
     61	xfs_trans_ail_delete(&buip->bui_item, 0);
     62	xfs_bui_item_free(buip);
     63}
     64
     65
     66STATIC void
     67xfs_bui_item_size(
     68	struct xfs_log_item	*lip,
     69	int			*nvecs,
     70	int			*nbytes)
     71{
     72	struct xfs_bui_log_item	*buip = BUI_ITEM(lip);
     73
     74	*nvecs += 1;
     75	*nbytes += xfs_bui_log_format_sizeof(buip->bui_format.bui_nextents);
     76}
     77
     78/*
     79 * This is called to fill in the vector of log iovecs for the
     80 * given bui log item. We use only 1 iovec, and we point that
     81 * at the bui_log_format structure embedded in the bui item.
     82 * It is at this point that we assert that all of the extent
     83 * slots in the bui item have been filled.
     84 */
     85STATIC void
     86xfs_bui_item_format(
     87	struct xfs_log_item	*lip,
     88	struct xfs_log_vec	*lv)
     89{
     90	struct xfs_bui_log_item	*buip = BUI_ITEM(lip);
     91	struct xfs_log_iovec	*vecp = NULL;
     92
     93	ASSERT(atomic_read(&buip->bui_next_extent) ==
     94			buip->bui_format.bui_nextents);
     95
     96	buip->bui_format.bui_type = XFS_LI_BUI;
     97	buip->bui_format.bui_size = 1;
     98
     99	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_BUI_FORMAT, &buip->bui_format,
    100			xfs_bui_log_format_sizeof(buip->bui_format.bui_nextents));
    101}
    102
    103/*
    104 * The unpin operation is the last place an BUI is manipulated in the log. It is
    105 * either inserted in the AIL or aborted in the event of a log I/O error. In
    106 * either case, the BUI transaction has been successfully committed to make it
    107 * this far. Therefore, we expect whoever committed the BUI to either construct
    108 * and commit the BUD or drop the BUD's reference in the event of error. Simply
    109 * drop the log's BUI reference now that the log is done with it.
    110 */
    111STATIC void
    112xfs_bui_item_unpin(
    113	struct xfs_log_item	*lip,
    114	int			remove)
    115{
    116	struct xfs_bui_log_item	*buip = BUI_ITEM(lip);
    117
    118	xfs_bui_release(buip);
    119}
    120
    121/*
    122 * The BUI has been either committed or aborted if the transaction has been
    123 * cancelled. If the transaction was cancelled, an BUD isn't going to be
    124 * constructed and thus we free the BUI here directly.
    125 */
    126STATIC void
    127xfs_bui_item_release(
    128	struct xfs_log_item	*lip)
    129{
    130	xfs_bui_release(BUI_ITEM(lip));
    131}
    132
    133/*
    134 * Allocate and initialize an bui item with the given number of extents.
    135 */
    136STATIC struct xfs_bui_log_item *
    137xfs_bui_init(
    138	struct xfs_mount		*mp)
    139
    140{
    141	struct xfs_bui_log_item		*buip;
    142
    143	buip = kmem_cache_zalloc(xfs_bui_cache, GFP_KERNEL | __GFP_NOFAIL);
    144
    145	xfs_log_item_init(mp, &buip->bui_item, XFS_LI_BUI, &xfs_bui_item_ops);
    146	buip->bui_format.bui_nextents = XFS_BUI_MAX_FAST_EXTENTS;
    147	buip->bui_format.bui_id = (uintptr_t)(void *)buip;
    148	atomic_set(&buip->bui_next_extent, 0);
    149	atomic_set(&buip->bui_refcount, 2);
    150
    151	return buip;
    152}
    153
    154static inline struct xfs_bud_log_item *BUD_ITEM(struct xfs_log_item *lip)
    155{
    156	return container_of(lip, struct xfs_bud_log_item, bud_item);
    157}
    158
    159STATIC void
    160xfs_bud_item_size(
    161	struct xfs_log_item	*lip,
    162	int			*nvecs,
    163	int			*nbytes)
    164{
    165	*nvecs += 1;
    166	*nbytes += sizeof(struct xfs_bud_log_format);
    167}
    168
    169/*
    170 * This is called to fill in the vector of log iovecs for the
    171 * given bud log item. We use only 1 iovec, and we point that
    172 * at the bud_log_format structure embedded in the bud item.
    173 * It is at this point that we assert that all of the extent
    174 * slots in the bud item have been filled.
    175 */
    176STATIC void
    177xfs_bud_item_format(
    178	struct xfs_log_item	*lip,
    179	struct xfs_log_vec	*lv)
    180{
    181	struct xfs_bud_log_item	*budp = BUD_ITEM(lip);
    182	struct xfs_log_iovec	*vecp = NULL;
    183
    184	budp->bud_format.bud_type = XFS_LI_BUD;
    185	budp->bud_format.bud_size = 1;
    186
    187	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_BUD_FORMAT, &budp->bud_format,
    188			sizeof(struct xfs_bud_log_format));
    189}
    190
    191/*
    192 * The BUD is either committed or aborted if the transaction is cancelled. If
    193 * the transaction is cancelled, drop our reference to the BUI and free the
    194 * BUD.
    195 */
    196STATIC void
    197xfs_bud_item_release(
    198	struct xfs_log_item	*lip)
    199{
    200	struct xfs_bud_log_item	*budp = BUD_ITEM(lip);
    201
    202	xfs_bui_release(budp->bud_buip);
    203	kmem_free(budp->bud_item.li_lv_shadow);
    204	kmem_cache_free(xfs_bud_cache, budp);
    205}
    206
    207static struct xfs_log_item *
    208xfs_bud_item_intent(
    209	struct xfs_log_item	*lip)
    210{
    211	return &BUD_ITEM(lip)->bud_buip->bui_item;
    212}
    213
    214static const struct xfs_item_ops xfs_bud_item_ops = {
    215	.flags		= XFS_ITEM_RELEASE_WHEN_COMMITTED |
    216			  XFS_ITEM_INTENT_DONE,
    217	.iop_size	= xfs_bud_item_size,
    218	.iop_format	= xfs_bud_item_format,
    219	.iop_release	= xfs_bud_item_release,
    220	.iop_intent	= xfs_bud_item_intent,
    221};
    222
    223static struct xfs_bud_log_item *
    224xfs_trans_get_bud(
    225	struct xfs_trans		*tp,
    226	struct xfs_bui_log_item		*buip)
    227{
    228	struct xfs_bud_log_item		*budp;
    229
    230	budp = kmem_cache_zalloc(xfs_bud_cache, GFP_KERNEL | __GFP_NOFAIL);
    231	xfs_log_item_init(tp->t_mountp, &budp->bud_item, XFS_LI_BUD,
    232			  &xfs_bud_item_ops);
    233	budp->bud_buip = buip;
    234	budp->bud_format.bud_bui_id = buip->bui_format.bui_id;
    235
    236	xfs_trans_add_item(tp, &budp->bud_item);
    237	return budp;
    238}
    239
    240/*
    241 * Finish an bmap update and log it to the BUD. Note that the
    242 * transaction is marked dirty regardless of whether the bmap update
    243 * succeeds or fails to support the BUI/BUD lifecycle rules.
    244 */
    245static int
    246xfs_trans_log_finish_bmap_update(
    247	struct xfs_trans		*tp,
    248	struct xfs_bud_log_item		*budp,
    249	enum xfs_bmap_intent_type	type,
    250	struct xfs_inode		*ip,
    251	int				whichfork,
    252	xfs_fileoff_t			startoff,
    253	xfs_fsblock_t			startblock,
    254	xfs_filblks_t			*blockcount,
    255	xfs_exntst_t			state)
    256{
    257	int				error;
    258
    259	error = xfs_bmap_finish_one(tp, ip, type, whichfork, startoff,
    260			startblock, blockcount, state);
    261
    262	/*
    263	 * Mark the transaction dirty, even on error. This ensures the
    264	 * transaction is aborted, which:
    265	 *
    266	 * 1.) releases the BUI and frees the BUD
    267	 * 2.) shuts down the filesystem
    268	 */
    269	tp->t_flags |= XFS_TRANS_DIRTY | XFS_TRANS_HAS_INTENT_DONE;
    270	set_bit(XFS_LI_DIRTY, &budp->bud_item.li_flags);
    271
    272	return error;
    273}
    274
    275/* Sort bmap intents by inode. */
    276static int
    277xfs_bmap_update_diff_items(
    278	void				*priv,
    279	const struct list_head		*a,
    280	const struct list_head		*b)
    281{
    282	struct xfs_bmap_intent		*ba;
    283	struct xfs_bmap_intent		*bb;
    284
    285	ba = container_of(a, struct xfs_bmap_intent, bi_list);
    286	bb = container_of(b, struct xfs_bmap_intent, bi_list);
    287	return ba->bi_owner->i_ino - bb->bi_owner->i_ino;
    288}
    289
    290/* Set the map extent flags for this mapping. */
    291static void
    292xfs_trans_set_bmap_flags(
    293	struct xfs_map_extent		*bmap,
    294	enum xfs_bmap_intent_type	type,
    295	int				whichfork,
    296	xfs_exntst_t			state)
    297{
    298	bmap->me_flags = 0;
    299	switch (type) {
    300	case XFS_BMAP_MAP:
    301	case XFS_BMAP_UNMAP:
    302		bmap->me_flags = type;
    303		break;
    304	default:
    305		ASSERT(0);
    306	}
    307	if (state == XFS_EXT_UNWRITTEN)
    308		bmap->me_flags |= XFS_BMAP_EXTENT_UNWRITTEN;
    309	if (whichfork == XFS_ATTR_FORK)
    310		bmap->me_flags |= XFS_BMAP_EXTENT_ATTR_FORK;
    311}
    312
    313/* Log bmap updates in the intent item. */
    314STATIC void
    315xfs_bmap_update_log_item(
    316	struct xfs_trans		*tp,
    317	struct xfs_bui_log_item		*buip,
    318	struct xfs_bmap_intent		*bmap)
    319{
    320	uint				next_extent;
    321	struct xfs_map_extent		*map;
    322
    323	tp->t_flags |= XFS_TRANS_DIRTY;
    324	set_bit(XFS_LI_DIRTY, &buip->bui_item.li_flags);
    325
    326	/*
    327	 * atomic_inc_return gives us the value after the increment;
    328	 * we want to use it as an array index so we need to subtract 1 from
    329	 * it.
    330	 */
    331	next_extent = atomic_inc_return(&buip->bui_next_extent) - 1;
    332	ASSERT(next_extent < buip->bui_format.bui_nextents);
    333	map = &buip->bui_format.bui_extents[next_extent];
    334	map->me_owner = bmap->bi_owner->i_ino;
    335	map->me_startblock = bmap->bi_bmap.br_startblock;
    336	map->me_startoff = bmap->bi_bmap.br_startoff;
    337	map->me_len = bmap->bi_bmap.br_blockcount;
    338	xfs_trans_set_bmap_flags(map, bmap->bi_type, bmap->bi_whichfork,
    339			bmap->bi_bmap.br_state);
    340}
    341
    342static struct xfs_log_item *
    343xfs_bmap_update_create_intent(
    344	struct xfs_trans		*tp,
    345	struct list_head		*items,
    346	unsigned int			count,
    347	bool				sort)
    348{
    349	struct xfs_mount		*mp = tp->t_mountp;
    350	struct xfs_bui_log_item		*buip = xfs_bui_init(mp);
    351	struct xfs_bmap_intent		*bmap;
    352
    353	ASSERT(count == XFS_BUI_MAX_FAST_EXTENTS);
    354
    355	xfs_trans_add_item(tp, &buip->bui_item);
    356	if (sort)
    357		list_sort(mp, items, xfs_bmap_update_diff_items);
    358	list_for_each_entry(bmap, items, bi_list)
    359		xfs_bmap_update_log_item(tp, buip, bmap);
    360	return &buip->bui_item;
    361}
    362
    363/* Get an BUD so we can process all the deferred rmap updates. */
    364static struct xfs_log_item *
    365xfs_bmap_update_create_done(
    366	struct xfs_trans		*tp,
    367	struct xfs_log_item		*intent,
    368	unsigned int			count)
    369{
    370	return &xfs_trans_get_bud(tp, BUI_ITEM(intent))->bud_item;
    371}
    372
    373/* Process a deferred rmap update. */
    374STATIC int
    375xfs_bmap_update_finish_item(
    376	struct xfs_trans		*tp,
    377	struct xfs_log_item		*done,
    378	struct list_head		*item,
    379	struct xfs_btree_cur		**state)
    380{
    381	struct xfs_bmap_intent		*bmap;
    382	xfs_filblks_t			count;
    383	int				error;
    384
    385	bmap = container_of(item, struct xfs_bmap_intent, bi_list);
    386	count = bmap->bi_bmap.br_blockcount;
    387	error = xfs_trans_log_finish_bmap_update(tp, BUD_ITEM(done),
    388			bmap->bi_type,
    389			bmap->bi_owner, bmap->bi_whichfork,
    390			bmap->bi_bmap.br_startoff,
    391			bmap->bi_bmap.br_startblock,
    392			&count,
    393			bmap->bi_bmap.br_state);
    394	if (!error && count > 0) {
    395		ASSERT(bmap->bi_type == XFS_BMAP_UNMAP);
    396		bmap->bi_bmap.br_blockcount = count;
    397		return -EAGAIN;
    398	}
    399	kmem_cache_free(xfs_bmap_intent_cache, bmap);
    400	return error;
    401}
    402
    403/* Abort all pending BUIs. */
    404STATIC void
    405xfs_bmap_update_abort_intent(
    406	struct xfs_log_item		*intent)
    407{
    408	xfs_bui_release(BUI_ITEM(intent));
    409}
    410
    411/* Cancel a deferred rmap update. */
    412STATIC void
    413xfs_bmap_update_cancel_item(
    414	struct list_head		*item)
    415{
    416	struct xfs_bmap_intent		*bmap;
    417
    418	bmap = container_of(item, struct xfs_bmap_intent, bi_list);
    419	kmem_cache_free(xfs_bmap_intent_cache, bmap);
    420}
    421
    422const struct xfs_defer_op_type xfs_bmap_update_defer_type = {
    423	.max_items	= XFS_BUI_MAX_FAST_EXTENTS,
    424	.create_intent	= xfs_bmap_update_create_intent,
    425	.abort_intent	= xfs_bmap_update_abort_intent,
    426	.create_done	= xfs_bmap_update_create_done,
    427	.finish_item	= xfs_bmap_update_finish_item,
    428	.cancel_item	= xfs_bmap_update_cancel_item,
    429};
    430
    431/* Is this recovered BUI ok? */
    432static inline bool
    433xfs_bui_validate(
    434	struct xfs_mount		*mp,
    435	struct xfs_bui_log_item		*buip)
    436{
    437	struct xfs_map_extent		*bmap;
    438
    439	/* Only one mapping operation per BUI... */
    440	if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
    441		return false;
    442
    443	bmap = &buip->bui_format.bui_extents[0];
    444
    445	if (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS)
    446		return false;
    447
    448	switch (bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK) {
    449	case XFS_BMAP_MAP:
    450	case XFS_BMAP_UNMAP:
    451		break;
    452	default:
    453		return false;
    454	}
    455
    456	if (!xfs_verify_ino(mp, bmap->me_owner))
    457		return false;
    458
    459	if (!xfs_verify_fileext(mp, bmap->me_startoff, bmap->me_len))
    460		return false;
    461
    462	return xfs_verify_fsbext(mp, bmap->me_startblock, bmap->me_len);
    463}
    464
    465/*
    466 * Process a bmap update intent item that was recovered from the log.
    467 * We need to update some inode's bmbt.
    468 */
    469STATIC int
    470xfs_bui_item_recover(
    471	struct xfs_log_item		*lip,
    472	struct list_head		*capture_list)
    473{
    474	struct xfs_bmbt_irec		irec;
    475	struct xfs_bui_log_item		*buip = BUI_ITEM(lip);
    476	struct xfs_trans		*tp;
    477	struct xfs_inode		*ip = NULL;
    478	struct xfs_mount		*mp = lip->li_log->l_mp;
    479	struct xfs_map_extent		*bmap;
    480	struct xfs_bud_log_item		*budp;
    481	xfs_filblks_t			count;
    482	xfs_exntst_t			state;
    483	unsigned int			bui_type;
    484	int				whichfork;
    485	int				iext_delta;
    486	int				error = 0;
    487
    488	if (!xfs_bui_validate(mp, buip)) {
    489		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
    490				&buip->bui_format, sizeof(buip->bui_format));
    491		return -EFSCORRUPTED;
    492	}
    493
    494	bmap = &buip->bui_format.bui_extents[0];
    495	state = (bmap->me_flags & XFS_BMAP_EXTENT_UNWRITTEN) ?
    496			XFS_EXT_UNWRITTEN : XFS_EXT_NORM;
    497	whichfork = (bmap->me_flags & XFS_BMAP_EXTENT_ATTR_FORK) ?
    498			XFS_ATTR_FORK : XFS_DATA_FORK;
    499	bui_type = bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK;
    500
    501	error = xlog_recover_iget(mp, bmap->me_owner, &ip);
    502	if (error)
    503		return error;
    504
    505	/* Allocate transaction and do the work. */
    506	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate,
    507			XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK), 0, 0, &tp);
    508	if (error)
    509		goto err_rele;
    510
    511	budp = xfs_trans_get_bud(tp, buip);
    512	xfs_ilock(ip, XFS_ILOCK_EXCL);
    513	xfs_trans_ijoin(tp, ip, 0);
    514
    515	if (bui_type == XFS_BMAP_MAP)
    516		iext_delta = XFS_IEXT_ADD_NOSPLIT_CNT;
    517	else
    518		iext_delta = XFS_IEXT_PUNCH_HOLE_CNT;
    519
    520	error = xfs_iext_count_may_overflow(ip, whichfork, iext_delta);
    521	if (error == -EFBIG)
    522		error = xfs_iext_count_upgrade(tp, ip, iext_delta);
    523	if (error)
    524		goto err_cancel;
    525
    526	count = bmap->me_len;
    527	error = xfs_trans_log_finish_bmap_update(tp, budp, bui_type, ip,
    528			whichfork, bmap->me_startoff, bmap->me_startblock,
    529			&count, state);
    530	if (error == -EFSCORRUPTED)
    531		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bmap,
    532				sizeof(*bmap));
    533	if (error)
    534		goto err_cancel;
    535
    536	if (count > 0) {
    537		ASSERT(bui_type == XFS_BMAP_UNMAP);
    538		irec.br_startblock = bmap->me_startblock;
    539		irec.br_blockcount = count;
    540		irec.br_startoff = bmap->me_startoff;
    541		irec.br_state = state;
    542		xfs_bmap_unmap_extent(tp, ip, &irec);
    543	}
    544
    545	/*
    546	 * Commit transaction, which frees the transaction and saves the inode
    547	 * for later replay activities.
    548	 */
    549	error = xfs_defer_ops_capture_and_commit(tp, capture_list);
    550	if (error)
    551		goto err_unlock;
    552
    553	xfs_iunlock(ip, XFS_ILOCK_EXCL);
    554	xfs_irele(ip);
    555	return 0;
    556
    557err_cancel:
    558	xfs_trans_cancel(tp);
    559err_unlock:
    560	xfs_iunlock(ip, XFS_ILOCK_EXCL);
    561err_rele:
    562	xfs_irele(ip);
    563	return error;
    564}
    565
    566STATIC bool
    567xfs_bui_item_match(
    568	struct xfs_log_item	*lip,
    569	uint64_t		intent_id)
    570{
    571	return BUI_ITEM(lip)->bui_format.bui_id == intent_id;
    572}
    573
    574/* Relog an intent item to push the log tail forward. */
    575static struct xfs_log_item *
    576xfs_bui_item_relog(
    577	struct xfs_log_item		*intent,
    578	struct xfs_trans		*tp)
    579{
    580	struct xfs_bud_log_item		*budp;
    581	struct xfs_bui_log_item		*buip;
    582	struct xfs_map_extent		*extp;
    583	unsigned int			count;
    584
    585	count = BUI_ITEM(intent)->bui_format.bui_nextents;
    586	extp = BUI_ITEM(intent)->bui_format.bui_extents;
    587
    588	tp->t_flags |= XFS_TRANS_DIRTY;
    589	budp = xfs_trans_get_bud(tp, BUI_ITEM(intent));
    590	set_bit(XFS_LI_DIRTY, &budp->bud_item.li_flags);
    591
    592	buip = xfs_bui_init(tp->t_mountp);
    593	memcpy(buip->bui_format.bui_extents, extp, count * sizeof(*extp));
    594	atomic_set(&buip->bui_next_extent, count);
    595	xfs_trans_add_item(tp, &buip->bui_item);
    596	set_bit(XFS_LI_DIRTY, &buip->bui_item.li_flags);
    597	return &buip->bui_item;
    598}
    599
    600static const struct xfs_item_ops xfs_bui_item_ops = {
    601	.flags		= XFS_ITEM_INTENT,
    602	.iop_size	= xfs_bui_item_size,
    603	.iop_format	= xfs_bui_item_format,
    604	.iop_unpin	= xfs_bui_item_unpin,
    605	.iop_release	= xfs_bui_item_release,
    606	.iop_recover	= xfs_bui_item_recover,
    607	.iop_match	= xfs_bui_item_match,
    608	.iop_relog	= xfs_bui_item_relog,
    609};
    610
    611/*
    612 * Copy an BUI format buffer from the given buf, and into the destination
    613 * BUI format structure.  The BUI/BUD items were designed not to need any
    614 * special alignment handling.
    615 */
    616static int
    617xfs_bui_copy_format(
    618	struct xfs_log_iovec		*buf,
    619	struct xfs_bui_log_format	*dst_bui_fmt)
    620{
    621	struct xfs_bui_log_format	*src_bui_fmt;
    622	uint				len;
    623
    624	src_bui_fmt = buf->i_addr;
    625	len = xfs_bui_log_format_sizeof(src_bui_fmt->bui_nextents);
    626
    627	if (buf->i_len == len) {
    628		memcpy(dst_bui_fmt, src_bui_fmt, len);
    629		return 0;
    630	}
    631	XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, NULL);
    632	return -EFSCORRUPTED;
    633}
    634
    635/*
    636 * This routine is called to create an in-core extent bmap update
    637 * item from the bui format structure which was logged on disk.
    638 * It allocates an in-core bui, copies the extents from the format
    639 * structure into it, and adds the bui to the AIL with the given
    640 * LSN.
    641 */
    642STATIC int
    643xlog_recover_bui_commit_pass2(
    644	struct xlog			*log,
    645	struct list_head		*buffer_list,
    646	struct xlog_recover_item	*item,
    647	xfs_lsn_t			lsn)
    648{
    649	int				error;
    650	struct xfs_mount		*mp = log->l_mp;
    651	struct xfs_bui_log_item		*buip;
    652	struct xfs_bui_log_format	*bui_formatp;
    653
    654	bui_formatp = item->ri_buf[0].i_addr;
    655
    656	if (bui_formatp->bui_nextents != XFS_BUI_MAX_FAST_EXTENTS) {
    657		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, log->l_mp);
    658		return -EFSCORRUPTED;
    659	}
    660	buip = xfs_bui_init(mp);
    661	error = xfs_bui_copy_format(&item->ri_buf[0], &buip->bui_format);
    662	if (error) {
    663		xfs_bui_item_free(buip);
    664		return error;
    665	}
    666	atomic_set(&buip->bui_next_extent, bui_formatp->bui_nextents);
    667	/*
    668	 * Insert the intent into the AIL directly and drop one reference so
    669	 * that finishing or canceling the work will drop the other.
    670	 */
    671	xfs_trans_ail_insert(log->l_ailp, &buip->bui_item, lsn);
    672	xfs_bui_release(buip);
    673	return 0;
    674}
    675
    676const struct xlog_recover_item_ops xlog_bui_item_ops = {
    677	.item_type		= XFS_LI_BUI,
    678	.commit_pass2		= xlog_recover_bui_commit_pass2,
    679};
    680
    681/*
    682 * This routine is called when an BUD format structure is found in a committed
    683 * transaction in the log. Its purpose is to cancel the corresponding BUI if it
    684 * was still in the log. To do this it searches the AIL for the BUI with an id
    685 * equal to that in the BUD format structure. If we find it we drop the BUD
    686 * reference, which removes the BUI from the AIL and frees it.
    687 */
    688STATIC int
    689xlog_recover_bud_commit_pass2(
    690	struct xlog			*log,
    691	struct list_head		*buffer_list,
    692	struct xlog_recover_item	*item,
    693	xfs_lsn_t			lsn)
    694{
    695	struct xfs_bud_log_format	*bud_formatp;
    696
    697	bud_formatp = item->ri_buf[0].i_addr;
    698	if (item->ri_buf[0].i_len != sizeof(struct xfs_bud_log_format)) {
    699		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, log->l_mp);
    700		return -EFSCORRUPTED;
    701	}
    702
    703	xlog_recover_release_intent(log, XFS_LI_BUI, bud_formatp->bud_bui_id);
    704	return 0;
    705}
    706
    707const struct xlog_recover_item_ops xlog_bud_item_ops = {
    708	.item_type		= XFS_LI_BUD,
    709	.commit_pass2		= xlog_recover_bud_commit_pass2,
    710};