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Diffstat (limited to '')
| -rw-r--r-- | fs/xfs/xfs_trans.c | 1113 |
1 files changed, 1113 insertions, 0 deletions
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c new file mode 100644 index 000000000..912b42f5f --- /dev/null +++ b/fs/xfs/xfs_trans.c @@ -0,0 +1,1113 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc. + * Copyright (C) 2010 Red Hat, Inc. + * All Rights Reserved. + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_inode.h" +#include "xfs_extent_busy.h" +#include "xfs_quota.h" +#include "xfs_trans.h" +#include "xfs_trans_priv.h" +#include "xfs_log.h" +#include "xfs_trace.h" +#include "xfs_error.h" +#include "xfs_defer.h" + +kmem_zone_t *xfs_trans_zone; + +#if defined(CONFIG_TRACEPOINTS) +static void +xfs_trans_trace_reservations( + struct xfs_mount *mp) +{ + struct xfs_trans_res resv; + struct xfs_trans_res *res; + struct xfs_trans_res *end_res; + int i; + + res = (struct xfs_trans_res *)M_RES(mp); + end_res = (struct xfs_trans_res *)(M_RES(mp) + 1); + for (i = 0; res < end_res; i++, res++) + trace_xfs_trans_resv_calc(mp, i, res); + xfs_log_get_max_trans_res(mp, &resv); + trace_xfs_trans_resv_calc(mp, -1, &resv); +} +#else +# define xfs_trans_trace_reservations(mp) +#endif + +/* + * Initialize the precomputed transaction reservation values + * in the mount structure. + */ +void +xfs_trans_init( + struct xfs_mount *mp) +{ + xfs_trans_resv_calc(mp, M_RES(mp)); + xfs_trans_trace_reservations(mp); +} + +/* + * Free the transaction structure. If there is more clean up + * to do when the structure is freed, add it here. + */ +STATIC void +xfs_trans_free( + struct xfs_trans *tp) +{ + xfs_extent_busy_sort(&tp->t_busy); + xfs_extent_busy_clear(tp->t_mountp, &tp->t_busy, false); + + trace_xfs_trans_free(tp, _RET_IP_); + atomic_dec(&tp->t_mountp->m_active_trans); + if (!(tp->t_flags & XFS_TRANS_NO_WRITECOUNT)) + sb_end_intwrite(tp->t_mountp->m_super); + xfs_trans_free_dqinfo(tp); + kmem_zone_free(xfs_trans_zone, tp); +} + +/* + * This is called to create a new transaction which will share the + * permanent log reservation of the given transaction. The remaining + * unused block and rt extent reservations are also inherited. This + * implies that the original transaction is no longer allowed to allocate + * blocks. Locks and log items, however, are no inherited. They must + * be added to the new transaction explicitly. + */ +STATIC struct xfs_trans * +xfs_trans_dup( + struct xfs_trans *tp) +{ + struct xfs_trans *ntp; + + trace_xfs_trans_dup(tp, _RET_IP_); + + ntp = kmem_zone_zalloc(xfs_trans_zone, KM_SLEEP); + + /* + * Initialize the new transaction structure. + */ + ntp->t_magic = XFS_TRANS_HEADER_MAGIC; + ntp->t_mountp = tp->t_mountp; + INIT_LIST_HEAD(&ntp->t_items); + INIT_LIST_HEAD(&ntp->t_busy); + INIT_LIST_HEAD(&ntp->t_dfops); + ntp->t_firstblock = NULLFSBLOCK; + + ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES); + ASSERT(tp->t_ticket != NULL); + + ntp->t_flags = XFS_TRANS_PERM_LOG_RES | + (tp->t_flags & XFS_TRANS_RESERVE) | + (tp->t_flags & XFS_TRANS_NO_WRITECOUNT); + /* We gave our writer reference to the new transaction */ + tp->t_flags |= XFS_TRANS_NO_WRITECOUNT; + ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket); + + ASSERT(tp->t_blk_res >= tp->t_blk_res_used); + ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used; + tp->t_blk_res = tp->t_blk_res_used; + + ntp->t_rtx_res = tp->t_rtx_res - tp->t_rtx_res_used; + tp->t_rtx_res = tp->t_rtx_res_used; + ntp->t_pflags = tp->t_pflags; + + /* move deferred ops over to the new tp */ + xfs_defer_move(ntp, tp); + + xfs_trans_dup_dqinfo(tp, ntp); + + atomic_inc(&tp->t_mountp->m_active_trans); + return ntp; +} + +/* + * This is called to reserve free disk blocks and log space for the + * given transaction. This must be done before allocating any resources + * within the transaction. + * + * This will return ENOSPC if there are not enough blocks available. + * It will sleep waiting for available log space. + * The only valid value for the flags parameter is XFS_RES_LOG_PERM, which + * is used by long running transactions. If any one of the reservations + * fails then they will all be backed out. + * + * This does not do quota reservations. That typically is done by the + * caller afterwards. + */ +static int +xfs_trans_reserve( + struct xfs_trans *tp, + struct xfs_trans_res *resp, + uint blocks, + uint rtextents) +{ + int error = 0; + bool rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0; + + /* Mark this thread as being in a transaction */ + current_set_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + + /* + * Attempt to reserve the needed disk blocks by decrementing + * the number needed from the number available. This will + * fail if the count would go below zero. + */ + if (blocks > 0) { + error = xfs_mod_fdblocks(tp->t_mountp, -((int64_t)blocks), rsvd); + if (error != 0) { + current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + return -ENOSPC; + } + tp->t_blk_res += blocks; + } + + /* + * Reserve the log space needed for this transaction. + */ + if (resp->tr_logres > 0) { + bool permanent = false; + + ASSERT(tp->t_log_res == 0 || + tp->t_log_res == resp->tr_logres); + ASSERT(tp->t_log_count == 0 || + tp->t_log_count == resp->tr_logcount); + + if (resp->tr_logflags & XFS_TRANS_PERM_LOG_RES) { + tp->t_flags |= XFS_TRANS_PERM_LOG_RES; + permanent = true; + } else { + ASSERT(tp->t_ticket == NULL); + ASSERT(!(tp->t_flags & XFS_TRANS_PERM_LOG_RES)); + } + + if (tp->t_ticket != NULL) { + ASSERT(resp->tr_logflags & XFS_TRANS_PERM_LOG_RES); + error = xfs_log_regrant(tp->t_mountp, tp->t_ticket); + } else { + error = xfs_log_reserve(tp->t_mountp, + resp->tr_logres, + resp->tr_logcount, + &tp->t_ticket, XFS_TRANSACTION, + permanent); + } + + if (error) + goto undo_blocks; + + tp->t_log_res = resp->tr_logres; + tp->t_log_count = resp->tr_logcount; + } + + /* + * Attempt to reserve the needed realtime extents by decrementing + * the number needed from the number available. This will + * fail if the count would go below zero. + */ + if (rtextents > 0) { + error = xfs_mod_frextents(tp->t_mountp, -((int64_t)rtextents)); + if (error) { + error = -ENOSPC; + goto undo_log; + } + tp->t_rtx_res += rtextents; + } + + return 0; + + /* + * Error cases jump to one of these labels to undo any + * reservations which have already been performed. + */ +undo_log: + if (resp->tr_logres > 0) { + xfs_log_done(tp->t_mountp, tp->t_ticket, NULL, false); + tp->t_ticket = NULL; + tp->t_log_res = 0; + tp->t_flags &= ~XFS_TRANS_PERM_LOG_RES; + } + +undo_blocks: + if (blocks > 0) { + xfs_mod_fdblocks(tp->t_mountp, (int64_t)blocks, rsvd); + tp->t_blk_res = 0; + } + + current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + + return error; +} + +int +xfs_trans_alloc( + struct xfs_mount *mp, + struct xfs_trans_res *resp, + uint blocks, + uint rtextents, + uint flags, + struct xfs_trans **tpp) +{ + struct xfs_trans *tp; + int error; + + /* + * Allocate the handle before we do our freeze accounting and setting up + * GFP_NOFS allocation context so that we avoid lockdep false positives + * by doing GFP_KERNEL allocations inside sb_start_intwrite(). + */ + tp = kmem_zone_zalloc(xfs_trans_zone, + (flags & XFS_TRANS_NOFS) ? KM_NOFS : KM_SLEEP); + + if (!(flags & XFS_TRANS_NO_WRITECOUNT)) + sb_start_intwrite(mp->m_super); + + /* + * Zero-reservation ("empty") transactions can't modify anything, so + * they're allowed to run while we're frozen. + */ + WARN_ON(resp->tr_logres > 0 && + mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE); + atomic_inc(&mp->m_active_trans); + + tp->t_magic = XFS_TRANS_HEADER_MAGIC; + tp->t_flags = flags; + tp->t_mountp = mp; + INIT_LIST_HEAD(&tp->t_items); + INIT_LIST_HEAD(&tp->t_busy); + INIT_LIST_HEAD(&tp->t_dfops); + tp->t_firstblock = NULLFSBLOCK; + + error = xfs_trans_reserve(tp, resp, blocks, rtextents); + if (error) { + xfs_trans_cancel(tp); + return error; + } + + trace_xfs_trans_alloc(tp, _RET_IP_); + + *tpp = tp; + return 0; +} + +/* + * Create an empty transaction with no reservation. This is a defensive + * mechanism for routines that query metadata without actually modifying + * them -- if the metadata being queried is somehow cross-linked (think a + * btree block pointer that points higher in the tree), we risk deadlock. + * However, blocks grabbed as part of a transaction can be re-grabbed. + * The verifiers will notice the corrupt block and the operation will fail + * back to userspace without deadlocking. + * + * Note the zero-length reservation; this transaction MUST be cancelled + * without any dirty data. + */ +int +xfs_trans_alloc_empty( + struct xfs_mount *mp, + struct xfs_trans **tpp) +{ + struct xfs_trans_res resv = {0}; + + return xfs_trans_alloc(mp, &resv, 0, 0, XFS_TRANS_NO_WRITECOUNT, tpp); +} + +/* + * Record the indicated change to the given field for application + * to the file system's superblock when the transaction commits. + * For now, just store the change in the transaction structure. + * + * Mark the transaction structure to indicate that the superblock + * needs to be updated before committing. + * + * Because we may not be keeping track of allocated/free inodes and + * used filesystem blocks in the superblock, we do not mark the + * superblock dirty in this transaction if we modify these fields. + * We still need to update the transaction deltas so that they get + * applied to the incore superblock, but we don't want them to + * cause the superblock to get locked and logged if these are the + * only fields in the superblock that the transaction modifies. + */ +void +xfs_trans_mod_sb( + xfs_trans_t *tp, + uint field, + int64_t delta) +{ + uint32_t flags = (XFS_TRANS_DIRTY|XFS_TRANS_SB_DIRTY); + xfs_mount_t *mp = tp->t_mountp; + + switch (field) { + case XFS_TRANS_SB_ICOUNT: + tp->t_icount_delta += delta; + if (xfs_sb_version_haslazysbcount(&mp->m_sb)) + flags &= ~XFS_TRANS_SB_DIRTY; + break; + case XFS_TRANS_SB_IFREE: + tp->t_ifree_delta += delta; + if (xfs_sb_version_haslazysbcount(&mp->m_sb)) + flags &= ~XFS_TRANS_SB_DIRTY; + break; + case XFS_TRANS_SB_FDBLOCKS: + /* + * Track the number of blocks allocated in the transaction. + * Make sure it does not exceed the number reserved. If so, + * shutdown as this can lead to accounting inconsistency. + */ + if (delta < 0) { + tp->t_blk_res_used += (uint)-delta; + if (tp->t_blk_res_used > tp->t_blk_res) + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); + } + tp->t_fdblocks_delta += delta; + if (xfs_sb_version_haslazysbcount(&mp->m_sb)) + flags &= ~XFS_TRANS_SB_DIRTY; + break; + case XFS_TRANS_SB_RES_FDBLOCKS: + /* + * The allocation has already been applied to the + * in-core superblock's counter. This should only + * be applied to the on-disk superblock. + */ + tp->t_res_fdblocks_delta += delta; + if (xfs_sb_version_haslazysbcount(&mp->m_sb)) + flags &= ~XFS_TRANS_SB_DIRTY; + break; + case XFS_TRANS_SB_FREXTENTS: + /* + * Track the number of blocks allocated in the + * transaction. Make sure it does not exceed the + * number reserved. + */ + if (delta < 0) { + tp->t_rtx_res_used += (uint)-delta; + ASSERT(tp->t_rtx_res_used <= tp->t_rtx_res); + } + tp->t_frextents_delta += delta; + break; + case XFS_TRANS_SB_RES_FREXTENTS: + /* + * The allocation has already been applied to the + * in-core superblock's counter. This should only + * be applied to the on-disk superblock. + */ + ASSERT(delta < 0); + tp->t_res_frextents_delta += delta; + break; + case XFS_TRANS_SB_DBLOCKS: + ASSERT(delta > 0); + tp->t_dblocks_delta += delta; + break; + case XFS_TRANS_SB_AGCOUNT: + ASSERT(delta > 0); + tp->t_agcount_delta += delta; + break; + case XFS_TRANS_SB_IMAXPCT: + tp->t_imaxpct_delta += delta; + break; + case XFS_TRANS_SB_REXTSIZE: + tp->t_rextsize_delta += delta; + break; + case XFS_TRANS_SB_RBMBLOCKS: + tp->t_rbmblocks_delta += delta; + break; + case XFS_TRANS_SB_RBLOCKS: + tp->t_rblocks_delta += delta; + break; + case XFS_TRANS_SB_REXTENTS: + tp->t_rextents_delta += delta; + break; + case XFS_TRANS_SB_REXTSLOG: + tp->t_rextslog_delta += delta; + break; + default: + ASSERT(0); + return; + } + + tp->t_flags |= flags; +} + +/* + * xfs_trans_apply_sb_deltas() is called from the commit code + * to bring the superblock buffer into the current transaction + * and modify it as requested by earlier calls to xfs_trans_mod_sb(). + * + * For now we just look at each field allowed to change and change + * it if necessary. + */ +STATIC void +xfs_trans_apply_sb_deltas( + xfs_trans_t *tp) +{ + xfs_dsb_t *sbp; + xfs_buf_t *bp; + int whole = 0; + + bp = xfs_trans_getsb(tp, tp->t_mountp, 0); + sbp = XFS_BUF_TO_SBP(bp); + + /* + * Check that superblock mods match the mods made to AGF counters. + */ + ASSERT((tp->t_fdblocks_delta + tp->t_res_fdblocks_delta) == + (tp->t_ag_freeblks_delta + tp->t_ag_flist_delta + + tp->t_ag_btree_delta)); + + /* + * Only update the superblock counters if we are logging them + */ + if (!xfs_sb_version_haslazysbcount(&(tp->t_mountp->m_sb))) { + if (tp->t_icount_delta) + be64_add_cpu(&sbp->sb_icount, tp->t_icount_delta); + if (tp->t_ifree_delta) + be64_add_cpu(&sbp->sb_ifree, tp->t_ifree_delta); + if (tp->t_fdblocks_delta) + be64_add_cpu(&sbp->sb_fdblocks, tp->t_fdblocks_delta); + if (tp->t_res_fdblocks_delta) + be64_add_cpu(&sbp->sb_fdblocks, tp->t_res_fdblocks_delta); + } + + if (tp->t_frextents_delta) + be64_add_cpu(&sbp->sb_frextents, tp->t_frextents_delta); + if (tp->t_res_frextents_delta) + be64_add_cpu(&sbp->sb_frextents, tp->t_res_frextents_delta); + + if (tp->t_dblocks_delta) { + be64_add_cpu(&sbp->sb_dblocks, tp->t_dblocks_delta); + whole = 1; + } + if (tp->t_agcount_delta) { + be32_add_cpu(&sbp->sb_agcount, tp->t_agcount_delta); + whole = 1; + } + if (tp->t_imaxpct_delta) { + sbp->sb_imax_pct += tp->t_imaxpct_delta; + whole = 1; + } + if (tp->t_rextsize_delta) { + be32_add_cpu(&sbp->sb_rextsize, tp->t_rextsize_delta); + whole = 1; + } + if (tp->t_rbmblocks_delta) { + be32_add_cpu(&sbp->sb_rbmblocks, tp->t_rbmblocks_delta); + whole = 1; + } + if (tp->t_rblocks_delta) { + be64_add_cpu(&sbp->sb_rblocks, tp->t_rblocks_delta); + whole = 1; + } + if (tp->t_rextents_delta) { + be64_add_cpu(&sbp->sb_rextents, tp->t_rextents_delta); + whole = 1; + } + if (tp->t_rextslog_delta) { + sbp->sb_rextslog += tp->t_rextslog_delta; + whole = 1; + } + + xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF); + if (whole) + /* + * Log the whole thing, the fields are noncontiguous. + */ + xfs_trans_log_buf(tp, bp, 0, sizeof(xfs_dsb_t) - 1); + else + /* + * Since all the modifiable fields are contiguous, we + * can get away with this. + */ + xfs_trans_log_buf(tp, bp, offsetof(xfs_dsb_t, sb_icount), + offsetof(xfs_dsb_t, sb_frextents) + + sizeof(sbp->sb_frextents) - 1); +} + +STATIC int +xfs_sb_mod8( + uint8_t *field, + int8_t delta) +{ + int8_t counter = *field; + + counter += delta; + if (counter < 0) { + ASSERT(0); + return -EINVAL; + } + *field = counter; + return 0; +} + +STATIC int +xfs_sb_mod32( + uint32_t *field, + int32_t delta) +{ + int32_t counter = *field; + + counter += delta; + if (counter < 0) { + ASSERT(0); + return -EINVAL; + } + *field = counter; + return 0; +} + +STATIC int +xfs_sb_mod64( + uint64_t *field, + int64_t delta) +{ + int64_t counter = *field; + + counter += delta; + if (counter < 0) { + ASSERT(0); + return -EINVAL; + } + *field = counter; + return 0; +} + +/* + * xfs_trans_unreserve_and_mod_sb() is called to release unused reservations + * and apply superblock counter changes to the in-core superblock. The + * t_res_fdblocks_delta and t_res_frextents_delta fields are explicitly NOT + * applied to the in-core superblock. The idea is that that has already been + * done. + * + * If we are not logging superblock counters, then the inode allocated/free and + * used block counts are not updated in the on disk superblock. In this case, + * XFS_TRANS_SB_DIRTY will not be set when the transaction is updated but we + * still need to update the incore superblock with the changes. + */ +void +xfs_trans_unreserve_and_mod_sb( + struct xfs_trans *tp) +{ + struct xfs_mount *mp = tp->t_mountp; + bool rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0; + int64_t blkdelta = 0; + int64_t rtxdelta = 0; + int64_t idelta = 0; + int64_t ifreedelta = 0; + int error; + + /* calculate deltas */ + if (tp->t_blk_res > 0) + blkdelta = tp->t_blk_res; + if ((tp->t_fdblocks_delta != 0) && + (xfs_sb_version_haslazysbcount(&mp->m_sb) || + (tp->t_flags & XFS_TRANS_SB_DIRTY))) + blkdelta += tp->t_fdblocks_delta; + + if (tp->t_rtx_res > 0) + rtxdelta = tp->t_rtx_res; + if ((tp->t_frextents_delta != 0) && + (tp->t_flags & XFS_TRANS_SB_DIRTY)) + rtxdelta += tp->t_frextents_delta; + + if (xfs_sb_version_haslazysbcount(&mp->m_sb) || + (tp->t_flags & XFS_TRANS_SB_DIRTY)) { + idelta = tp->t_icount_delta; + ifreedelta = tp->t_ifree_delta; + } + + /* apply the per-cpu counters */ + if (blkdelta) { + error = xfs_mod_fdblocks(mp, blkdelta, rsvd); + if (error) + goto out; + } + + if (idelta) { + error = xfs_mod_icount(mp, idelta); + if (error) + goto out_undo_fdblocks; + } + + if (ifreedelta) { + error = xfs_mod_ifree(mp, ifreedelta); + if (error) + goto out_undo_icount; + } + + if (rtxdelta == 0 && !(tp->t_flags & XFS_TRANS_SB_DIRTY)) + return; + + /* apply remaining deltas */ + spin_lock(&mp->m_sb_lock); + if (rtxdelta) { + error = xfs_sb_mod64(&mp->m_sb.sb_frextents, rtxdelta); + if (error) + goto out_undo_ifree; + } + + if (tp->t_dblocks_delta != 0) { + error = xfs_sb_mod64(&mp->m_sb.sb_dblocks, tp->t_dblocks_delta); + if (error) + goto out_undo_frextents; + } + if (tp->t_agcount_delta != 0) { + error = xfs_sb_mod32(&mp->m_sb.sb_agcount, tp->t_agcount_delta); + if (error) + goto out_undo_dblocks; + } + if (tp->t_imaxpct_delta != 0) { + error = xfs_sb_mod8(&mp->m_sb.sb_imax_pct, tp->t_imaxpct_delta); + if (error) + goto out_undo_agcount; + } + if (tp->t_rextsize_delta != 0) { + error = xfs_sb_mod32(&mp->m_sb.sb_rextsize, + tp->t_rextsize_delta); + if (error) + goto out_undo_imaxpct; + } + if (tp->t_rbmblocks_delta != 0) { + error = xfs_sb_mod32(&mp->m_sb.sb_rbmblocks, + tp->t_rbmblocks_delta); + if (error) + goto out_undo_rextsize; + } + if (tp->t_rblocks_delta != 0) { + error = xfs_sb_mod64(&mp->m_sb.sb_rblocks, tp->t_rblocks_delta); + if (error) + goto out_undo_rbmblocks; + } + if (tp->t_rextents_delta != 0) { + error = xfs_sb_mod64(&mp->m_sb.sb_rextents, + tp->t_rextents_delta); + if (error) + goto out_undo_rblocks; + } + if (tp->t_rextslog_delta != 0) { + error = xfs_sb_mod8(&mp->m_sb.sb_rextslog, + tp->t_rextslog_delta); + if (error) + goto out_undo_rextents; + } + spin_unlock(&mp->m_sb_lock); + return; + +out_undo_rextents: + if (tp->t_rextents_delta) + xfs_sb_mod64(&mp->m_sb.sb_rextents, -tp->t_rextents_delta); +out_undo_rblocks: + if (tp->t_rblocks_delta) + xfs_sb_mod64(&mp->m_sb.sb_rblocks, -tp->t_rblocks_delta); +out_undo_rbmblocks: + if (tp->t_rbmblocks_delta) + xfs_sb_mod32(&mp->m_sb.sb_rbmblocks, -tp->t_rbmblocks_delta); +out_undo_rextsize: + if (tp->t_rextsize_delta) + xfs_sb_mod32(&mp->m_sb.sb_rextsize, -tp->t_rextsize_delta); +out_undo_imaxpct: + if (tp->t_rextsize_delta) + xfs_sb_mod8(&mp->m_sb.sb_imax_pct, -tp->t_imaxpct_delta); +out_undo_agcount: + if (tp->t_agcount_delta) + xfs_sb_mod32(&mp->m_sb.sb_agcount, -tp->t_agcount_delta); +out_undo_dblocks: + if (tp->t_dblocks_delta) + xfs_sb_mod64(&mp->m_sb.sb_dblocks, -tp->t_dblocks_delta); +out_undo_frextents: + if (rtxdelta) + xfs_sb_mod64(&mp->m_sb.sb_frextents, -rtxdelta); +out_undo_ifree: + spin_unlock(&mp->m_sb_lock); + if (ifreedelta) + xfs_mod_ifree(mp, -ifreedelta); +out_undo_icount: + if (idelta) + xfs_mod_icount(mp, -idelta); +out_undo_fdblocks: + if (blkdelta) + xfs_mod_fdblocks(mp, -blkdelta, rsvd); +out: + ASSERT(error == 0); + return; +} + +/* Add the given log item to the transaction's list of log items. */ +void +xfs_trans_add_item( + struct xfs_trans *tp, + struct xfs_log_item *lip) +{ + ASSERT(lip->li_mountp == tp->t_mountp); + ASSERT(lip->li_ailp == tp->t_mountp->m_ail); + ASSERT(list_empty(&lip->li_trans)); + ASSERT(!test_bit(XFS_LI_DIRTY, &lip->li_flags)); + + list_add_tail(&lip->li_trans, &tp->t_items); + trace_xfs_trans_add_item(tp, _RET_IP_); +} + +/* + * Unlink the log item from the transaction. the log item is no longer + * considered dirty in this transaction, as the linked transaction has + * finished, either by abort or commit completion. + */ +void +xfs_trans_del_item( + struct xfs_log_item *lip) +{ + clear_bit(XFS_LI_DIRTY, &lip->li_flags); + list_del_init(&lip->li_trans); +} + +/* Detach and unlock all of the items in a transaction */ +void +xfs_trans_free_items( + struct xfs_trans *tp, + xfs_lsn_t commit_lsn, + bool abort) +{ + struct xfs_log_item *lip, *next; + + trace_xfs_trans_free_items(tp, _RET_IP_); + + list_for_each_entry_safe(lip, next, &tp->t_items, li_trans) { + xfs_trans_del_item(lip); + if (commit_lsn != NULLCOMMITLSN) + lip->li_ops->iop_committing(lip, commit_lsn); + if (abort) + set_bit(XFS_LI_ABORTED, &lip->li_flags); + lip->li_ops->iop_unlock(lip); + } +} + +static inline void +xfs_log_item_batch_insert( + struct xfs_ail *ailp, + struct xfs_ail_cursor *cur, + struct xfs_log_item **log_items, + int nr_items, + xfs_lsn_t commit_lsn) +{ + int i; + + spin_lock(&ailp->ail_lock); + /* xfs_trans_ail_update_bulk drops ailp->ail_lock */ + xfs_trans_ail_update_bulk(ailp, cur, log_items, nr_items, commit_lsn); + + for (i = 0; i < nr_items; i++) { + struct xfs_log_item *lip = log_items[i]; + + lip->li_ops->iop_unpin(lip, 0); + } +} + +/* + * Bulk operation version of xfs_trans_committed that takes a log vector of + * items to insert into the AIL. This uses bulk AIL insertion techniques to + * minimise lock traffic. + * + * If we are called with the aborted flag set, it is because a log write during + * a CIL checkpoint commit has failed. In this case, all the items in the + * checkpoint have already gone through iop_commited and iop_unlock, which + * means that checkpoint commit abort handling is treated exactly the same + * as an iclog write error even though we haven't started any IO yet. Hence in + * this case all we need to do is iop_committed processing, followed by an + * iop_unpin(aborted) call. + * + * The AIL cursor is used to optimise the insert process. If commit_lsn is not + * at the end of the AIL, the insert cursor avoids the need to walk + * the AIL to find the insertion point on every xfs_log_item_batch_insert() + * call. This saves a lot of needless list walking and is a net win, even + * though it slightly increases that amount of AIL lock traffic to set it up + * and tear it down. + */ +void +xfs_trans_committed_bulk( + struct xfs_ail *ailp, + struct xfs_log_vec *log_vector, + xfs_lsn_t commit_lsn, + int aborted) +{ +#define LOG_ITEM_BATCH_SIZE 32 + struct xfs_log_item *log_items[LOG_ITEM_BATCH_SIZE]; + struct xfs_log_vec *lv; + struct xfs_ail_cursor cur; + int i = 0; + + spin_lock(&ailp->ail_lock); + xfs_trans_ail_cursor_last(ailp, &cur, commit_lsn); + spin_unlock(&ailp->ail_lock); + + /* unpin all the log items */ + for (lv = log_vector; lv; lv = lv->lv_next ) { + struct xfs_log_item *lip = lv->lv_item; + xfs_lsn_t item_lsn; + + if (aborted) + set_bit(XFS_LI_ABORTED, &lip->li_flags); + item_lsn = lip->li_ops->iop_committed(lip, commit_lsn); + + /* item_lsn of -1 means the item needs no further processing */ + if (XFS_LSN_CMP(item_lsn, (xfs_lsn_t)-1) == 0) + continue; + + /* + * if we are aborting the operation, no point in inserting the + * object into the AIL as we are in a shutdown situation. + */ + if (aborted) { + ASSERT(XFS_FORCED_SHUTDOWN(ailp->ail_mount)); + lip->li_ops->iop_unpin(lip, 1); + continue; + } + + if (item_lsn != commit_lsn) { + + /* + * Not a bulk update option due to unusual item_lsn. + * Push into AIL immediately, rechecking the lsn once + * we have the ail lock. Then unpin the item. This does + * not affect the AIL cursor the bulk insert path is + * using. + */ + spin_lock(&ailp->ail_lock); + if (XFS_LSN_CMP(item_lsn, lip->li_lsn) > 0) + xfs_trans_ail_update(ailp, lip, item_lsn); + else + spin_unlock(&ailp->ail_lock); + lip->li_ops->iop_unpin(lip, 0); + continue; + } + + /* Item is a candidate for bulk AIL insert. */ + log_items[i++] = lv->lv_item; + if (i >= LOG_ITEM_BATCH_SIZE) { + xfs_log_item_batch_insert(ailp, &cur, log_items, + LOG_ITEM_BATCH_SIZE, commit_lsn); + i = 0; + } + } + + /* make sure we insert the remainder! */ + if (i) + xfs_log_item_batch_insert(ailp, &cur, log_items, i, commit_lsn); + + spin_lock(&ailp->ail_lock); + xfs_trans_ail_cursor_done(&cur); + spin_unlock(&ailp->ail_lock); +} + +/* + * Commit the given transaction to the log. + * + * XFS disk error handling mechanism is not based on a typical + * transaction abort mechanism. Logically after the filesystem + * gets marked 'SHUTDOWN', we can't let any new transactions + * be durable - ie. committed to disk - because some metadata might + * be inconsistent. In such cases, this returns an error, and the + * caller may assume that all locked objects joined to the transaction + * have already been unlocked as if the commit had succeeded. + * Do not reference the transaction structure after this call. + */ +static int +__xfs_trans_commit( + struct xfs_trans *tp, + bool regrant) +{ + struct xfs_mount *mp = tp->t_mountp; + xfs_lsn_t commit_lsn = -1; + int error = 0; + int sync = tp->t_flags & XFS_TRANS_SYNC; + + trace_xfs_trans_commit(tp, _RET_IP_); + + /* + * Finish deferred items on final commit. Only permanent transactions + * should ever have deferred ops. + */ + WARN_ON_ONCE(!list_empty(&tp->t_dfops) && + !(tp->t_flags & XFS_TRANS_PERM_LOG_RES)); + if (!regrant && (tp->t_flags & XFS_TRANS_PERM_LOG_RES)) { + error = xfs_defer_finish_noroll(&tp); + if (error) + goto out_unreserve; + } + + /* + * If there is nothing to be logged by the transaction, + * then unlock all of the items associated with the + * transaction and free the transaction structure. + * Also make sure to return any reserved blocks to + * the free pool. + */ + if (!(tp->t_flags & XFS_TRANS_DIRTY)) + goto out_unreserve; + + if (XFS_FORCED_SHUTDOWN(mp)) { + error = -EIO; + goto out_unreserve; + } + + ASSERT(tp->t_ticket != NULL); + + /* + * If we need to update the superblock, then do it now. + */ + if (tp->t_flags & XFS_TRANS_SB_DIRTY) + xfs_trans_apply_sb_deltas(tp); + xfs_trans_apply_dquot_deltas(tp); + + xfs_log_commit_cil(mp, tp, &commit_lsn, regrant); + + current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_free(tp); + + /* + * If the transaction needs to be synchronous, then force the + * log out now and wait for it. + */ + if (sync) { + error = xfs_log_force_lsn(mp, commit_lsn, XFS_LOG_SYNC, NULL); + XFS_STATS_INC(mp, xs_trans_sync); + } else { + XFS_STATS_INC(mp, xs_trans_async); + } + + return error; + +out_unreserve: + xfs_trans_unreserve_and_mod_sb(tp); + + /* + * It is indeed possible for the transaction to be not dirty but + * the dqinfo portion to be. All that means is that we have some + * (non-persistent) quota reservations that need to be unreserved. + */ + xfs_trans_unreserve_and_mod_dquots(tp); + if (tp->t_ticket) { + commit_lsn = xfs_log_done(mp, tp->t_ticket, NULL, regrant); + if (commit_lsn == -1 && !error) + error = -EIO; + tp->t_ticket = NULL; + } + current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_free_items(tp, NULLCOMMITLSN, !!error); + xfs_trans_free(tp); + + XFS_STATS_INC(mp, xs_trans_empty); + return error; +} + +int +xfs_trans_commit( + struct xfs_trans *tp) +{ + return __xfs_trans_commit(tp, false); +} + +/* + * Unlock all of the transaction's items and free the transaction. + * The transaction must not have modified any of its items, because + * there is no way to restore them to their previous state. + * + * If the transaction has made a log reservation, make sure to release + * it as well. + */ +void +xfs_trans_cancel( + struct xfs_trans *tp) +{ + struct xfs_mount *mp = tp->t_mountp; + bool dirty = (tp->t_flags & XFS_TRANS_DIRTY); + + trace_xfs_trans_cancel(tp, _RET_IP_); + + if (tp->t_flags & XFS_TRANS_PERM_LOG_RES) + xfs_defer_cancel(tp); + + /* + * See if the caller is relying on us to shut down the + * filesystem. This happens in paths where we detect + * corruption and decide to give up. + */ + if (dirty && !XFS_FORCED_SHUTDOWN(mp)) { + XFS_ERROR_REPORT("xfs_trans_cancel", XFS_ERRLEVEL_LOW, mp); + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); + } +#ifdef DEBUG + if (!dirty && !XFS_FORCED_SHUTDOWN(mp)) { + struct xfs_log_item *lip; + + list_for_each_entry(lip, &tp->t_items, li_trans) + ASSERT(!(lip->li_type == XFS_LI_EFD)); + } +#endif + xfs_trans_unreserve_and_mod_sb(tp); + xfs_trans_unreserve_and_mod_dquots(tp); + + if (tp->t_ticket) { + xfs_log_done(mp, tp->t_ticket, NULL, false); + tp->t_ticket = NULL; + } + + /* mark this thread as no longer being in a transaction */ + current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + + xfs_trans_free_items(tp, NULLCOMMITLSN, dirty); + xfs_trans_free(tp); +} + +/* + * Roll from one trans in the sequence of PERMANENT transactions to + * the next: permanent transactions are only flushed out when + * committed with xfs_trans_commit(), but we still want as soon + * as possible to let chunks of it go to the log. So we commit the + * chunk we've been working on and get a new transaction to continue. + */ +int +xfs_trans_roll( + struct xfs_trans **tpp) +{ + struct xfs_trans *trans = *tpp; + struct xfs_trans_res tres; + int error; + + trace_xfs_trans_roll(trans, _RET_IP_); + + /* + * Copy the critical parameters from one trans to the next. + */ + tres.tr_logres = trans->t_log_res; + tres.tr_logcount = trans->t_log_count; + + *tpp = xfs_trans_dup(trans); + + /* + * Commit the current transaction. + * If this commit failed, then it'd just unlock those items that + * are not marked ihold. That also means that a filesystem shutdown + * is in progress. The caller takes the responsibility to cancel + * the duplicate transaction that gets returned. + */ + error = __xfs_trans_commit(trans, true); + if (error) + return error; + + /* + * Reserve space in the log for the next transaction. + * This also pushes items in the "AIL", the list of logged items, + * out to disk if they are taking up space at the tail of the log + * that we want to use. This requires that either nothing be locked + * across this call, or that anything that is locked be logged in + * the prior and the next transactions. + */ + tres.tr_logflags = XFS_TRANS_PERM_LOG_RES; + return xfs_trans_reserve(*tpp, &tres, 0, 0); +} |