1118 lines
31 KiB
C
1118 lines
31 KiB
C
/*
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* Copyright (c) 2000-2002 Silicon Graphics, Inc. All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of version 2 of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it would be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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*
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* Further, this software is distributed without any warranty that it is
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* free of the rightful claim of any third person regarding infringement
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* or the like. Any license provided herein, whether implied or
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* otherwise, applies only to this software file. Patent licenses, if
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* any, provided herein do not apply to combinations of this program with
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* other software, or any other product whatsoever.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write the Free Software Foundation, Inc., 59
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* Temple Place - Suite 330, Boston MA 02111-1307, USA.
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*
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* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
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* Mountain View, CA 94043, or:
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*
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* http://www.sgi.com
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*
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* For further information regarding this notice, see:
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*
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* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
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*/
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#include "xfs.h"
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#include "xfs_macros.h"
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#include "xfs_types.h"
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#include "xfs_inum.h"
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#include "xfs_log.h"
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#include "xfs_trans.h"
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#include "xfs_buf_item.h"
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#include "xfs_sb.h"
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#include "xfs_ag.h"
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#include "xfs_dir.h"
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#include "xfs_dmapi.h"
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#include "xfs_mount.h"
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#include "xfs_trans_priv.h"
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#include "xfs_error.h"
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#include "xfs_rw.h"
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STATIC xfs_buf_t *xfs_trans_buf_item_match(xfs_trans_t *, xfs_buftarg_t *,
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xfs_daddr_t, int);
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STATIC xfs_buf_t *xfs_trans_buf_item_match_all(xfs_trans_t *, xfs_buftarg_t *,
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xfs_daddr_t, int);
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/*
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* Get and lock the buffer for the caller if it is not already
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* locked within the given transaction. If it is already locked
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* within the transaction, just increment its lock recursion count
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* and return a pointer to it.
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*
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* Use the fast path function xfs_trans_buf_item_match() or the buffer
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* cache routine incore_match() to find the buffer
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* if it is already owned by this transaction.
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*
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* If we don't already own the buffer, use get_buf() to get it.
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* If it doesn't yet have an associated xfs_buf_log_item structure,
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* then allocate one and add the item to this transaction.
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*
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* If the transaction pointer is NULL, make this just a normal
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* get_buf() call.
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*/
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xfs_buf_t *
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xfs_trans_get_buf(xfs_trans_t *tp,
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xfs_buftarg_t *target_dev,
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xfs_daddr_t blkno,
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int len,
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uint flags)
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{
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xfs_buf_t *bp;
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xfs_buf_log_item_t *bip;
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if (flags == 0)
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flags = XFS_BUF_LOCK | XFS_BUF_MAPPED;
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/*
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* Default to a normal get_buf() call if the tp is NULL.
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*/
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if (tp == NULL) {
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bp = xfs_buf_get_flags(target_dev, blkno, len,
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flags | BUF_BUSY);
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return(bp);
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}
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/*
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* If we find the buffer in the cache with this transaction
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* pointer in its b_fsprivate2 field, then we know we already
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* have it locked. In this case we just increment the lock
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* recursion count and return the buffer to the caller.
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*/
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if (tp->t_items.lic_next == NULL) {
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bp = xfs_trans_buf_item_match(tp, target_dev, blkno, len);
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} else {
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bp = xfs_trans_buf_item_match_all(tp, target_dev, blkno, len);
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}
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if (bp != NULL) {
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ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
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if (XFS_FORCED_SHUTDOWN(tp->t_mountp)) {
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xfs_buftrace("TRANS GET RECUR SHUT", bp);
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XFS_BUF_SUPER_STALE(bp);
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}
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/*
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* If the buffer is stale then it was binval'ed
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* since last read. This doesn't matter since the
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* caller isn't allowed to use the data anyway.
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*/
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else if (XFS_BUF_ISSTALE(bp)) {
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xfs_buftrace("TRANS GET RECUR STALE", bp);
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ASSERT(!XFS_BUF_ISDELAYWRITE(bp));
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}
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ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
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bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
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ASSERT(bip != NULL);
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ASSERT(atomic_read(&bip->bli_refcount) > 0);
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bip->bli_recur++;
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xfs_buftrace("TRANS GET RECUR", bp);
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xfs_buf_item_trace("GET RECUR", bip);
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return (bp);
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}
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/*
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* We always specify the BUF_BUSY flag within a transaction so
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* that get_buf does not try to push out a delayed write buffer
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* which might cause another transaction to take place (if the
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* buffer was delayed alloc). Such recursive transactions can
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* easily deadlock with our current transaction as well as cause
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* us to run out of stack space.
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*/
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bp = xfs_buf_get_flags(target_dev, blkno, len, flags | BUF_BUSY);
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if (bp == NULL) {
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return NULL;
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}
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ASSERT(!XFS_BUF_GETERROR(bp));
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/*
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* The xfs_buf_log_item pointer is stored in b_fsprivate. If
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* it doesn't have one yet, then allocate one and initialize it.
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* The checks to see if one is there are in xfs_buf_item_init().
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*/
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xfs_buf_item_init(bp, tp->t_mountp);
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/*
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* Set the recursion count for the buffer within this transaction
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* to 0.
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*/
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bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
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ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
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ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL));
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ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
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bip->bli_recur = 0;
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/*
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* Take a reference for this transaction on the buf item.
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*/
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atomic_inc(&bip->bli_refcount);
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/*
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* Get a log_item_desc to point at the new item.
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*/
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(void) xfs_trans_add_item(tp, (xfs_log_item_t*)bip);
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/*
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* Initialize b_fsprivate2 so we can find it with incore_match()
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* above.
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*/
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XFS_BUF_SET_FSPRIVATE2(bp, tp);
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xfs_buftrace("TRANS GET", bp);
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xfs_buf_item_trace("GET", bip);
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return (bp);
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}
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/*
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* Get and lock the superblock buffer of this file system for the
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* given transaction.
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*
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* We don't need to use incore_match() here, because the superblock
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* buffer is a private buffer which we keep a pointer to in the
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* mount structure.
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*/
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xfs_buf_t *
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xfs_trans_getsb(xfs_trans_t *tp,
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struct xfs_mount *mp,
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int flags)
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{
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xfs_buf_t *bp;
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xfs_buf_log_item_t *bip;
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/*
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* Default to just trying to lock the superblock buffer
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* if tp is NULL.
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*/
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if (tp == NULL) {
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return (xfs_getsb(mp, flags));
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}
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/*
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* If the superblock buffer already has this transaction
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* pointer in its b_fsprivate2 field, then we know we already
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* have it locked. In this case we just increment the lock
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* recursion count and return the buffer to the caller.
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*/
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bp = mp->m_sb_bp;
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if (XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp) {
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bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
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ASSERT(bip != NULL);
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ASSERT(atomic_read(&bip->bli_refcount) > 0);
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bip->bli_recur++;
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xfs_buf_item_trace("GETSB RECUR", bip);
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return (bp);
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}
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bp = xfs_getsb(mp, flags);
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if (bp == NULL) {
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return NULL;
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}
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/*
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* The xfs_buf_log_item pointer is stored in b_fsprivate. If
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* it doesn't have one yet, then allocate one and initialize it.
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* The checks to see if one is there are in xfs_buf_item_init().
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*/
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xfs_buf_item_init(bp, mp);
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/*
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* Set the recursion count for the buffer within this transaction
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* to 0.
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*/
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bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
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ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
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ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL));
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ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
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bip->bli_recur = 0;
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/*
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* Take a reference for this transaction on the buf item.
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*/
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atomic_inc(&bip->bli_refcount);
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/*
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* Get a log_item_desc to point at the new item.
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*/
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(void) xfs_trans_add_item(tp, (xfs_log_item_t*)bip);
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/*
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* Initialize b_fsprivate2 so we can find it with incore_match()
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* above.
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*/
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XFS_BUF_SET_FSPRIVATE2(bp, tp);
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xfs_buf_item_trace("GETSB", bip);
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return (bp);
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}
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#ifdef DEBUG
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xfs_buftarg_t *xfs_error_target;
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int xfs_do_error;
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int xfs_req_num;
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int xfs_error_mod = 33;
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#endif
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/*
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* Get and lock the buffer for the caller if it is not already
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* locked within the given transaction. If it has not yet been
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* read in, read it from disk. If it is already locked
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* within the transaction and already read in, just increment its
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* lock recursion count and return a pointer to it.
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*
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* Use the fast path function xfs_trans_buf_item_match() or the buffer
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* cache routine incore_match() to find the buffer
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* if it is already owned by this transaction.
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*
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* If we don't already own the buffer, use read_buf() to get it.
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* If it doesn't yet have an associated xfs_buf_log_item structure,
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* then allocate one and add the item to this transaction.
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*
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* If the transaction pointer is NULL, make this just a normal
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* read_buf() call.
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*/
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int
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xfs_trans_read_buf(
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xfs_mount_t *mp,
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xfs_trans_t *tp,
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xfs_buftarg_t *target,
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xfs_daddr_t blkno,
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int len,
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uint flags,
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xfs_buf_t **bpp)
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{
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xfs_buf_t *bp;
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xfs_buf_log_item_t *bip;
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int error;
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if (flags == 0)
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flags = XFS_BUF_LOCK | XFS_BUF_MAPPED;
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/*
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* Default to a normal get_buf() call if the tp is NULL.
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*/
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if (tp == NULL) {
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bp = xfs_buf_read_flags(target, blkno, len, flags | BUF_BUSY);
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if (!bp)
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return XFS_ERROR(ENOMEM);
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if ((bp != NULL) && (XFS_BUF_GETERROR(bp) != 0)) {
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xfs_ioerror_alert("xfs_trans_read_buf", mp,
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bp, blkno);
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error = XFS_BUF_GETERROR(bp);
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xfs_buf_relse(bp);
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return error;
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}
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#ifdef DEBUG
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if (xfs_do_error && (bp != NULL)) {
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if (xfs_error_target == target) {
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if (((xfs_req_num++) % xfs_error_mod) == 0) {
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xfs_buf_relse(bp);
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printk("Returning error!\n");
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return XFS_ERROR(EIO);
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}
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}
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}
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#endif
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if (XFS_FORCED_SHUTDOWN(mp))
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goto shutdown_abort;
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*bpp = bp;
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return 0;
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}
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|
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/*
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* If we find the buffer in the cache with this transaction
|
|
* pointer in its b_fsprivate2 field, then we know we already
|
|
* have it locked. If it is already read in we just increment
|
|
* the lock recursion count and return the buffer to the caller.
|
|
* If the buffer is not yet read in, then we read it in, increment
|
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* the lock recursion count, and return it to the caller.
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*/
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if (tp->t_items.lic_next == NULL) {
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bp = xfs_trans_buf_item_match(tp, target, blkno, len);
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} else {
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bp = xfs_trans_buf_item_match_all(tp, target, blkno, len);
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}
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if (bp != NULL) {
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ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
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ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
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ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
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ASSERT((XFS_BUF_ISERROR(bp)) == 0);
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if (!(XFS_BUF_ISDONE(bp))) {
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xfs_buftrace("READ_BUF_INCORE !DONE", bp);
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ASSERT(!XFS_BUF_ISASYNC(bp));
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XFS_BUF_READ(bp);
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xfsbdstrat(tp->t_mountp, bp);
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xfs_iowait(bp);
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if (XFS_BUF_GETERROR(bp) != 0) {
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xfs_ioerror_alert("xfs_trans_read_buf", mp,
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bp, blkno);
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error = XFS_BUF_GETERROR(bp);
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xfs_buf_relse(bp);
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/*
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* We can gracefully recover from most
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* read errors. Ones we can't are those
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* that happen after the transaction's
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* already dirty.
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*/
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if (tp->t_flags & XFS_TRANS_DIRTY)
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xfs_force_shutdown(tp->t_mountp,
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XFS_METADATA_IO_ERROR);
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return error;
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}
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}
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/*
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* We never locked this buf ourselves, so we shouldn't
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* brelse it either. Just get out.
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*/
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if (XFS_FORCED_SHUTDOWN(mp)) {
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xfs_buftrace("READ_BUF_INCORE XFSSHUTDN", bp);
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*bpp = NULL;
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return XFS_ERROR(EIO);
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}
|
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|
|
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bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
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bip->bli_recur++;
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|
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ASSERT(atomic_read(&bip->bli_refcount) > 0);
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xfs_buf_item_trace("READ RECUR", bip);
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*bpp = bp;
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return 0;
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}
|
|
|
|
/*
|
|
* We always specify the BUF_BUSY flag within a transaction so
|
|
* that get_buf does not try to push out a delayed write buffer
|
|
* which might cause another transaction to take place (if the
|
|
* buffer was delayed alloc). Such recursive transactions can
|
|
* easily deadlock with our current transaction as well as cause
|
|
* us to run out of stack space.
|
|
*/
|
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bp = xfs_buf_read_flags(target, blkno, len, flags | BUF_BUSY);
|
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if (bp == NULL) {
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*bpp = NULL;
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return 0;
|
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}
|
|
if (XFS_BUF_GETERROR(bp) != 0) {
|
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XFS_BUF_SUPER_STALE(bp);
|
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xfs_buftrace("READ ERROR", bp);
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error = XFS_BUF_GETERROR(bp);
|
|
|
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xfs_ioerror_alert("xfs_trans_read_buf", mp,
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bp, blkno);
|
|
if (tp->t_flags & XFS_TRANS_DIRTY)
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|
xfs_force_shutdown(tp->t_mountp, XFS_METADATA_IO_ERROR);
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xfs_buf_relse(bp);
|
|
return error;
|
|
}
|
|
#ifdef DEBUG
|
|
if (xfs_do_error && !(tp->t_flags & XFS_TRANS_DIRTY)) {
|
|
if (xfs_error_target == target) {
|
|
if (((xfs_req_num++) % xfs_error_mod) == 0) {
|
|
xfs_force_shutdown(tp->t_mountp,
|
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XFS_METADATA_IO_ERROR);
|
|
xfs_buf_relse(bp);
|
|
printk("Returning error in trans!\n");
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return XFS_ERROR(EIO);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
if (XFS_FORCED_SHUTDOWN(mp))
|
|
goto shutdown_abort;
|
|
|
|
/*
|
|
* The xfs_buf_log_item pointer is stored in b_fsprivate. If
|
|
* it doesn't have one yet, then allocate one and initialize it.
|
|
* The checks to see if one is there are in xfs_buf_item_init().
|
|
*/
|
|
xfs_buf_item_init(bp, tp->t_mountp);
|
|
|
|
/*
|
|
* Set the recursion count for the buffer within this transaction
|
|
* to 0.
|
|
*/
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
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|
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
|
|
ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL));
|
|
ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
|
|
bip->bli_recur = 0;
|
|
|
|
/*
|
|
* Take a reference for this transaction on the buf item.
|
|
*/
|
|
atomic_inc(&bip->bli_refcount);
|
|
|
|
/*
|
|
* Get a log_item_desc to point at the new item.
|
|
*/
|
|
(void) xfs_trans_add_item(tp, (xfs_log_item_t*)bip);
|
|
|
|
/*
|
|
* Initialize b_fsprivate2 so we can find it with incore_match()
|
|
* above.
|
|
*/
|
|
XFS_BUF_SET_FSPRIVATE2(bp, tp);
|
|
|
|
xfs_buftrace("TRANS READ", bp);
|
|
xfs_buf_item_trace("READ", bip);
|
|
*bpp = bp;
|
|
return 0;
|
|
|
|
shutdown_abort:
|
|
/*
|
|
* the theory here is that buffer is good but we're
|
|
* bailing out because the filesystem is being forcibly
|
|
* shut down. So we should leave the b_flags alone since
|
|
* the buffer's not staled and just get out.
|
|
*/
|
|
#if defined(DEBUG)
|
|
if (XFS_BUF_ISSTALE(bp) && XFS_BUF_ISDELAYWRITE(bp))
|
|
cmn_err(CE_NOTE, "about to pop assert, bp == 0x%p", bp);
|
|
#endif
|
|
ASSERT((XFS_BUF_BFLAGS(bp) & (XFS_B_STALE|XFS_B_DELWRI)) !=
|
|
(XFS_B_STALE|XFS_B_DELWRI));
|
|
|
|
xfs_buftrace("READ_BUF XFSSHUTDN", bp);
|
|
xfs_buf_relse(bp);
|
|
*bpp = NULL;
|
|
return XFS_ERROR(EIO);
|
|
}
|
|
|
|
|
|
/*
|
|
* Release the buffer bp which was previously acquired with one of the
|
|
* xfs_trans_... buffer allocation routines if the buffer has not
|
|
* been modified within this transaction. If the buffer is modified
|
|
* within this transaction, do decrement the recursion count but do
|
|
* not release the buffer even if the count goes to 0. If the buffer is not
|
|
* modified within the transaction, decrement the recursion count and
|
|
* release the buffer if the recursion count goes to 0.
|
|
*
|
|
* If the buffer is to be released and it was not modified before
|
|
* this transaction began, then free the buf_log_item associated with it.
|
|
*
|
|
* If the transaction pointer is NULL, make this just a normal
|
|
* brelse() call.
|
|
*/
|
|
void
|
|
xfs_trans_brelse(xfs_trans_t *tp,
|
|
xfs_buf_t *bp)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
xfs_log_item_t *lip;
|
|
xfs_log_item_desc_t *lidp;
|
|
|
|
/*
|
|
* Default to a normal brelse() call if the tp is NULL.
|
|
*/
|
|
if (tp == NULL) {
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, void *) == NULL);
|
|
/*
|
|
* If there's a buf log item attached to the buffer,
|
|
* then let the AIL know that the buffer is being
|
|
* unlocked.
|
|
*/
|
|
if (XFS_BUF_FSPRIVATE(bp, void *) != NULL) {
|
|
lip = XFS_BUF_FSPRIVATE(bp, xfs_log_item_t *);
|
|
if (lip->li_type == XFS_LI_BUF) {
|
|
bip = XFS_BUF_FSPRIVATE(bp,xfs_buf_log_item_t*);
|
|
xfs_trans_unlocked_item(
|
|
bip->bli_item.li_mountp,
|
|
lip);
|
|
}
|
|
}
|
|
xfs_buf_relse(bp);
|
|
return;
|
|
}
|
|
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
|
|
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
|
|
ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL));
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
|
|
/*
|
|
* Find the item descriptor pointing to this buffer's
|
|
* log item. It must be there.
|
|
*/
|
|
lidp = xfs_trans_find_item(tp, (xfs_log_item_t*)bip);
|
|
ASSERT(lidp != NULL);
|
|
|
|
/*
|
|
* If the release is just for a recursive lock,
|
|
* then decrement the count and return.
|
|
*/
|
|
if (bip->bli_recur > 0) {
|
|
bip->bli_recur--;
|
|
xfs_buf_item_trace("RELSE RECUR", bip);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the buffer is dirty within this transaction, we can't
|
|
* release it until we commit.
|
|
*/
|
|
if (lidp->lid_flags & XFS_LID_DIRTY) {
|
|
xfs_buf_item_trace("RELSE DIRTY", bip);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the buffer has been invalidated, then we can't release
|
|
* it until the transaction commits to disk unless it is re-dirtied
|
|
* as part of this transaction. This prevents us from pulling
|
|
* the item from the AIL before we should.
|
|
*/
|
|
if (bip->bli_flags & XFS_BLI_STALE) {
|
|
xfs_buf_item_trace("RELSE STALE", bip);
|
|
return;
|
|
}
|
|
|
|
ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
|
|
xfs_buf_item_trace("RELSE", bip);
|
|
|
|
/*
|
|
* Free up the log item descriptor tracking the released item.
|
|
*/
|
|
xfs_trans_free_item(tp, lidp);
|
|
|
|
/*
|
|
* Clear the hold flag in the buf log item if it is set.
|
|
* We wouldn't want the next user of the buffer to
|
|
* get confused.
|
|
*/
|
|
if (bip->bli_flags & XFS_BLI_HOLD) {
|
|
bip->bli_flags &= ~XFS_BLI_HOLD;
|
|
}
|
|
|
|
/*
|
|
* Drop our reference to the buf log item.
|
|
*/
|
|
atomic_dec(&bip->bli_refcount);
|
|
|
|
/*
|
|
* If the buf item is not tracking data in the log, then
|
|
* we must free it before releasing the buffer back to the
|
|
* free pool. Before releasing the buffer to the free pool,
|
|
* clear the transaction pointer in b_fsprivate2 to dissolve
|
|
* its relation to this transaction.
|
|
*/
|
|
if (!xfs_buf_item_dirty(bip)) {
|
|
/***
|
|
ASSERT(bp->b_pincount == 0);
|
|
***/
|
|
ASSERT(atomic_read(&bip->bli_refcount) == 0);
|
|
ASSERT(!(bip->bli_item.li_flags & XFS_LI_IN_AIL));
|
|
ASSERT(!(bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF));
|
|
xfs_buf_item_relse(bp);
|
|
bip = NULL;
|
|
}
|
|
XFS_BUF_SET_FSPRIVATE2(bp, NULL);
|
|
|
|
/*
|
|
* If we've still got a buf log item on the buffer, then
|
|
* tell the AIL that the buffer is being unlocked.
|
|
*/
|
|
if (bip != NULL) {
|
|
xfs_trans_unlocked_item(bip->bli_item.li_mountp,
|
|
(xfs_log_item_t*)bip);
|
|
}
|
|
|
|
xfs_buf_relse(bp);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Add the locked buffer to the transaction.
|
|
* The buffer must be locked, and it cannot be associated with any
|
|
* transaction.
|
|
*
|
|
* If the buffer does not yet have a buf log item associated with it,
|
|
* then allocate one for it. Then add the buf item to the transaction.
|
|
*/
|
|
void
|
|
xfs_trans_bjoin(xfs_trans_t *tp,
|
|
xfs_buf_t *bp)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, void *) == NULL);
|
|
|
|
/*
|
|
* The xfs_buf_log_item pointer is stored in b_fsprivate. If
|
|
* it doesn't have one yet, then allocate one and initialize it.
|
|
* The checks to see if one is there are in xfs_buf_item_init().
|
|
*/
|
|
xfs_buf_item_init(bp, tp->t_mountp);
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
|
|
ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL));
|
|
ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
|
|
|
|
/*
|
|
* Take a reference for this transaction on the buf item.
|
|
*/
|
|
atomic_inc(&bip->bli_refcount);
|
|
|
|
/*
|
|
* Get a log_item_desc to point at the new item.
|
|
*/
|
|
(void) xfs_trans_add_item(tp, (xfs_log_item_t *)bip);
|
|
|
|
/*
|
|
* Initialize b_fsprivate2 so we can find it with incore_match()
|
|
* in xfs_trans_get_buf() and friends above.
|
|
*/
|
|
XFS_BUF_SET_FSPRIVATE2(bp, tp);
|
|
|
|
xfs_buf_item_trace("BJOIN", bip);
|
|
}
|
|
|
|
/*
|
|
* Mark the buffer as not needing to be unlocked when the buf item's
|
|
* IOP_UNLOCK() routine is called. The buffer must already be locked
|
|
* and associated with the given transaction.
|
|
*/
|
|
/* ARGSUSED */
|
|
void
|
|
xfs_trans_bhold(xfs_trans_t *tp,
|
|
xfs_buf_t *bp)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
|
|
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
|
|
ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL));
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
bip->bli_flags |= XFS_BLI_HOLD;
|
|
xfs_buf_item_trace("BHOLD", bip);
|
|
}
|
|
|
|
/*
|
|
* Cancel the previous buffer hold request made on this buffer
|
|
* for this transaction.
|
|
*/
|
|
void
|
|
xfs_trans_bhold_release(xfs_trans_t *tp,
|
|
xfs_buf_t *bp)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
|
|
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
|
|
ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL));
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
ASSERT(bip->bli_flags & XFS_BLI_HOLD);
|
|
bip->bli_flags &= ~XFS_BLI_HOLD;
|
|
xfs_buf_item_trace("BHOLD RELEASE", bip);
|
|
}
|
|
|
|
/*
|
|
* This is called to mark bytes first through last inclusive of the given
|
|
* buffer as needing to be logged when the transaction is committed.
|
|
* The buffer must already be associated with the given transaction.
|
|
*
|
|
* First and last are numbers relative to the beginning of this buffer,
|
|
* so the first byte in the buffer is numbered 0 regardless of the
|
|
* value of b_blkno.
|
|
*/
|
|
void
|
|
xfs_trans_log_buf(xfs_trans_t *tp,
|
|
xfs_buf_t *bp,
|
|
uint first,
|
|
uint last)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
xfs_log_item_desc_t *lidp;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
|
|
ASSERT((first <= last) && (last < XFS_BUF_COUNT(bp)));
|
|
ASSERT((XFS_BUF_IODONE_FUNC(bp) == NULL) ||
|
|
(XFS_BUF_IODONE_FUNC(bp) == xfs_buf_iodone_callbacks));
|
|
|
|
/*
|
|
* Mark the buffer as needing to be written out eventually,
|
|
* and set its iodone function to remove the buffer's buf log
|
|
* item from the AIL and free it when the buffer is flushed
|
|
* to disk. See xfs_buf_attach_iodone() for more details
|
|
* on li_cb and xfs_buf_iodone_callbacks().
|
|
* If we end up aborting this transaction, we trap this buffer
|
|
* inside the b_bdstrat callback so that this won't get written to
|
|
* disk.
|
|
*/
|
|
XFS_BUF_DELAYWRITE(bp);
|
|
XFS_BUF_DONE(bp);
|
|
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
XFS_BUF_SET_IODONE_FUNC(bp, xfs_buf_iodone_callbacks);
|
|
bip->bli_item.li_cb = (void(*)(xfs_buf_t*,xfs_log_item_t*))xfs_buf_iodone;
|
|
|
|
/*
|
|
* If we invalidated the buffer within this transaction, then
|
|
* cancel the invalidation now that we're dirtying the buffer
|
|
* again. There are no races with the code in xfs_buf_item_unpin(),
|
|
* because we have a reference to the buffer this entire time.
|
|
*/
|
|
if (bip->bli_flags & XFS_BLI_STALE) {
|
|
xfs_buf_item_trace("BLOG UNSTALE", bip);
|
|
bip->bli_flags &= ~XFS_BLI_STALE;
|
|
ASSERT(XFS_BUF_ISSTALE(bp));
|
|
XFS_BUF_UNSTALE(bp);
|
|
bip->bli_format.blf_flags &= ~XFS_BLI_CANCEL;
|
|
}
|
|
|
|
lidp = xfs_trans_find_item(tp, (xfs_log_item_t*)bip);
|
|
ASSERT(lidp != NULL);
|
|
|
|
tp->t_flags |= XFS_TRANS_DIRTY;
|
|
lidp->lid_flags |= XFS_LID_DIRTY;
|
|
lidp->lid_flags &= ~XFS_LID_BUF_STALE;
|
|
bip->bli_flags |= XFS_BLI_LOGGED;
|
|
xfs_buf_item_log(bip, first, last);
|
|
xfs_buf_item_trace("BLOG", bip);
|
|
}
|
|
|
|
|
|
/*
|
|
* This called to invalidate a buffer that is being used within
|
|
* a transaction. Typically this is because the blocks in the
|
|
* buffer are being freed, so we need to prevent it from being
|
|
* written out when we're done. Allowing it to be written again
|
|
* might overwrite data in the free blocks if they are reallocated
|
|
* to a file.
|
|
*
|
|
* We prevent the buffer from being written out by clearing the
|
|
* B_DELWRI flag. We can't always
|
|
* get rid of the buf log item at this point, though, because
|
|
* the buffer may still be pinned by another transaction. If that
|
|
* is the case, then we'll wait until the buffer is committed to
|
|
* disk for the last time (we can tell by the ref count) and
|
|
* free it in xfs_buf_item_unpin(). Until it is cleaned up we
|
|
* will keep the buffer locked so that the buffer and buf log item
|
|
* are not reused.
|
|
*/
|
|
void
|
|
xfs_trans_binval(
|
|
xfs_trans_t *tp,
|
|
xfs_buf_t *bp)
|
|
{
|
|
xfs_log_item_desc_t *lidp;
|
|
xfs_buf_log_item_t *bip;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
|
|
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
lidp = xfs_trans_find_item(tp, (xfs_log_item_t*)bip);
|
|
ASSERT(lidp != NULL);
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
|
|
if (bip->bli_flags & XFS_BLI_STALE) {
|
|
/*
|
|
* If the buffer is already invalidated, then
|
|
* just return.
|
|
*/
|
|
ASSERT(!(XFS_BUF_ISDELAYWRITE(bp)));
|
|
ASSERT(XFS_BUF_ISSTALE(bp));
|
|
ASSERT(!(bip->bli_flags & (XFS_BLI_LOGGED | XFS_BLI_DIRTY)));
|
|
ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_INODE_BUF));
|
|
ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL);
|
|
ASSERT(lidp->lid_flags & XFS_LID_DIRTY);
|
|
ASSERT(tp->t_flags & XFS_TRANS_DIRTY);
|
|
xfs_buftrace("XFS_BINVAL RECUR", bp);
|
|
xfs_buf_item_trace("BINVAL RECUR", bip);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Clear the dirty bit in the buffer and set the STALE flag
|
|
* in the buf log item. The STALE flag will be used in
|
|
* xfs_buf_item_unpin() to determine if it should clean up
|
|
* when the last reference to the buf item is given up.
|
|
* We set the XFS_BLI_CANCEL flag in the buf log format structure
|
|
* and log the buf item. This will be used at recovery time
|
|
* to determine that copies of the buffer in the log before
|
|
* this should not be replayed.
|
|
* We mark the item descriptor and the transaction dirty so
|
|
* that we'll hold the buffer until after the commit.
|
|
*
|
|
* Since we're invalidating the buffer, we also clear the state
|
|
* about which parts of the buffer have been logged. We also
|
|
* clear the flag indicating that this is an inode buffer since
|
|
* the data in the buffer will no longer be valid.
|
|
*
|
|
* We set the stale bit in the buffer as well since we're getting
|
|
* rid of it.
|
|
*/
|
|
XFS_BUF_UNDELAYWRITE(bp);
|
|
XFS_BUF_STALE(bp);
|
|
bip->bli_flags |= XFS_BLI_STALE;
|
|
bip->bli_flags &= ~(XFS_BLI_LOGGED | XFS_BLI_DIRTY);
|
|
bip->bli_format.blf_flags &= ~XFS_BLI_INODE_BUF;
|
|
bip->bli_format.blf_flags |= XFS_BLI_CANCEL;
|
|
memset((char *)(bip->bli_format.blf_data_map), 0,
|
|
(bip->bli_format.blf_map_size * sizeof(uint)));
|
|
lidp->lid_flags |= XFS_LID_DIRTY|XFS_LID_BUF_STALE;
|
|
tp->t_flags |= XFS_TRANS_DIRTY;
|
|
xfs_buftrace("XFS_BINVAL", bp);
|
|
xfs_buf_item_trace("BINVAL", bip);
|
|
}
|
|
|
|
/*
|
|
* This call is used to indicate that the buffer contains on-disk
|
|
* inodes which must be handled specially during recovery. They
|
|
* require special handling because only the di_next_unlinked from
|
|
* the inodes in the buffer should be recovered. The rest of the
|
|
* data in the buffer is logged via the inodes themselves.
|
|
*
|
|
* All we do is set the XFS_BLI_INODE_BUF flag in the buffer's log
|
|
* format structure so that we'll know what to do at recovery time.
|
|
*/
|
|
/* ARGSUSED */
|
|
void
|
|
xfs_trans_inode_buf(
|
|
xfs_trans_t *tp,
|
|
xfs_buf_t *bp)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
|
|
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
|
|
bip->bli_format.blf_flags |= XFS_BLI_INODE_BUF;
|
|
}
|
|
|
|
/*
|
|
* This call is used to indicate that the buffer is going to
|
|
* be staled and was an inode buffer. This means it gets
|
|
* special processing during unpin - where any inodes
|
|
* associated with the buffer should be removed from ail.
|
|
* There is also special processing during recovery,
|
|
* any replay of the inodes in the buffer needs to be
|
|
* prevented as the buffer may have been reused.
|
|
*/
|
|
void
|
|
xfs_trans_stale_inode_buf(
|
|
xfs_trans_t *tp,
|
|
xfs_buf_t *bp)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
|
|
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
|
|
bip->bli_flags |= XFS_BLI_STALE_INODE;
|
|
bip->bli_item.li_cb = (void(*)(xfs_buf_t*,xfs_log_item_t*))
|
|
xfs_buf_iodone;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
* Mark the buffer as being one which contains newly allocated
|
|
* inodes. We need to make sure that even if this buffer is
|
|
* relogged as an 'inode buf' we still recover all of the inode
|
|
* images in the face of a crash. This works in coordination with
|
|
* xfs_buf_item_committed() to ensure that the buffer remains in the
|
|
* AIL at its original location even after it has been relogged.
|
|
*/
|
|
/* ARGSUSED */
|
|
void
|
|
xfs_trans_inode_alloc_buf(
|
|
xfs_trans_t *tp,
|
|
xfs_buf_t *bp)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
|
|
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
|
|
bip->bli_flags |= XFS_BLI_INODE_ALLOC_BUF;
|
|
}
|
|
|
|
|
|
/*
|
|
* Similar to xfs_trans_inode_buf(), this marks the buffer as a cluster of
|
|
* dquots. However, unlike in inode buffer recovery, dquot buffers get
|
|
* recovered in their entirety. (Hence, no XFS_BLI_DQUOT_ALLOC_BUF flag).
|
|
* The only thing that makes dquot buffers different from regular
|
|
* buffers is that we must not replay dquot bufs when recovering
|
|
* if a _corresponding_ quotaoff has happened. We also have to distinguish
|
|
* between usr dquot bufs and grp dquot bufs, because usr and grp quotas
|
|
* can be turned off independently.
|
|
*/
|
|
/* ARGSUSED */
|
|
void
|
|
xfs_trans_dquot_buf(
|
|
xfs_trans_t *tp,
|
|
xfs_buf_t *bp,
|
|
uint type)
|
|
{
|
|
xfs_buf_log_item_t *bip;
|
|
|
|
ASSERT(XFS_BUF_ISBUSY(bp));
|
|
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
|
|
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
|
|
ASSERT(type == XFS_BLI_UDQUOT_BUF ||
|
|
type == XFS_BLI_PDQUOT_BUF ||
|
|
type == XFS_BLI_GDQUOT_BUF);
|
|
|
|
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
|
|
ASSERT(atomic_read(&bip->bli_refcount) > 0);
|
|
|
|
bip->bli_format.blf_flags |= type;
|
|
}
|
|
|
|
/*
|
|
* Check to see if a buffer matching the given parameters is already
|
|
* a part of the given transaction. Only check the first, embedded
|
|
* chunk, since we don't want to spend all day scanning large transactions.
|
|
*/
|
|
STATIC xfs_buf_t *
|
|
xfs_trans_buf_item_match(
|
|
xfs_trans_t *tp,
|
|
xfs_buftarg_t *target,
|
|
xfs_daddr_t blkno,
|
|
int len)
|
|
{
|
|
xfs_log_item_chunk_t *licp;
|
|
xfs_log_item_desc_t *lidp;
|
|
xfs_buf_log_item_t *blip;
|
|
xfs_buf_t *bp;
|
|
int i;
|
|
|
|
bp = NULL;
|
|
len = BBTOB(len);
|
|
licp = &tp->t_items;
|
|
if (!XFS_LIC_ARE_ALL_FREE(licp)) {
|
|
for (i = 0; i < licp->lic_unused; i++) {
|
|
/*
|
|
* Skip unoccupied slots.
|
|
*/
|
|
if (XFS_LIC_ISFREE(licp, i)) {
|
|
continue;
|
|
}
|
|
|
|
lidp = XFS_LIC_SLOT(licp, i);
|
|
blip = (xfs_buf_log_item_t *)lidp->lid_item;
|
|
if (blip->bli_item.li_type != XFS_LI_BUF) {
|
|
continue;
|
|
}
|
|
|
|
bp = blip->bli_buf;
|
|
if ((XFS_BUF_TARGET(bp) == target) &&
|
|
(XFS_BUF_ADDR(bp) == blkno) &&
|
|
(XFS_BUF_COUNT(bp) == len)) {
|
|
/*
|
|
* We found it. Break out and
|
|
* return the pointer to the buffer.
|
|
*/
|
|
break;
|
|
} else {
|
|
bp = NULL;
|
|
}
|
|
}
|
|
}
|
|
return bp;
|
|
}
|
|
|
|
/*
|
|
* Check to see if a buffer matching the given parameters is already
|
|
* a part of the given transaction. Check all the chunks, we
|
|
* want to be thorough.
|
|
*/
|
|
STATIC xfs_buf_t *
|
|
xfs_trans_buf_item_match_all(
|
|
xfs_trans_t *tp,
|
|
xfs_buftarg_t *target,
|
|
xfs_daddr_t blkno,
|
|
int len)
|
|
{
|
|
xfs_log_item_chunk_t *licp;
|
|
xfs_log_item_desc_t *lidp;
|
|
xfs_buf_log_item_t *blip;
|
|
xfs_buf_t *bp;
|
|
int i;
|
|
|
|
bp = NULL;
|
|
len = BBTOB(len);
|
|
for (licp = &tp->t_items; licp != NULL; licp = licp->lic_next) {
|
|
if (XFS_LIC_ARE_ALL_FREE(licp)) {
|
|
ASSERT(licp == &tp->t_items);
|
|
ASSERT(licp->lic_next == NULL);
|
|
return NULL;
|
|
}
|
|
for (i = 0; i < licp->lic_unused; i++) {
|
|
/*
|
|
* Skip unoccupied slots.
|
|
*/
|
|
if (XFS_LIC_ISFREE(licp, i)) {
|
|
continue;
|
|
}
|
|
|
|
lidp = XFS_LIC_SLOT(licp, i);
|
|
blip = (xfs_buf_log_item_t *)lidp->lid_item;
|
|
if (blip->bli_item.li_type != XFS_LI_BUF) {
|
|
continue;
|
|
}
|
|
|
|
bp = blip->bli_buf;
|
|
if ((XFS_BUF_TARGET(bp) == target) &&
|
|
(XFS_BUF_ADDR(bp) == blkno) &&
|
|
(XFS_BUF_COUNT(bp) == len)) {
|
|
/*
|
|
* We found it. Break out and
|
|
* return the pointer to the buffer.
|
|
*/
|
|
return bp;
|
|
}
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|