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-rw-r--r--fs/xfs/xfs_trans_buf.c1093
1 files changed, 1093 insertions, 0 deletions
diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
new file mode 100644
index 00000000000..a9682b9510c
--- /dev/null
+++ b/fs/xfs/xfs_trans_buf.c
@@ -0,0 +1,1093 @@
+/*
+ * Copyright (c) 2000-2002 Silicon Graphics, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like. Any license provided herein, whether implied or
+ * otherwise, applies only to this software file. Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA 94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include "xfs.h"
+#include "xfs_macros.h"
+#include "xfs_types.h"
+#include "xfs_inum.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_buf_item.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_dir.h"
+#include "xfs_dmapi.h"
+#include "xfs_mount.h"
+#include "xfs_trans_priv.h"
+#include "xfs_error.h"
+#include "xfs_rw.h"
+
+
+STATIC xfs_buf_t *xfs_trans_buf_item_match(xfs_trans_t *, xfs_buftarg_t *,
+ xfs_daddr_t, int);
+STATIC xfs_buf_t *xfs_trans_buf_item_match_all(xfs_trans_t *, xfs_buftarg_t *,
+ xfs_daddr_t, int);
+
+
+/*
+ * Get and lock the buffer for the caller if it is not already
+ * locked within the given transaction. If it is already locked
+ * within the transaction, just increment its lock recursion count
+ * and return a pointer to it.
+ *
+ * Use the fast path function xfs_trans_buf_item_match() or the buffer
+ * cache routine incore_match() to find the buffer
+ * if it is already owned by this transaction.
+ *
+ * If we don't already own the buffer, use get_buf() to get it.
+ * If it doesn't yet have an associated xfs_buf_log_item structure,
+ * then allocate one and add the item to this transaction.
+ *
+ * If the transaction pointer is NULL, make this just a normal
+ * get_buf() call.
+ */
+xfs_buf_t *
+xfs_trans_get_buf(xfs_trans_t *tp,
+ xfs_buftarg_t *target_dev,
+ xfs_daddr_t blkno,
+ int len,
+ uint flags)
+{
+ xfs_buf_t *bp;
+ xfs_buf_log_item_t *bip;
+
+ if (flags == 0)
+ flags = XFS_BUF_LOCK | XFS_BUF_MAPPED;
+
+ /*
+ * Default to a normal get_buf() call if the tp is NULL.
+ */
+ if (tp == NULL) {
+ bp = xfs_buf_get_flags(target_dev, blkno, len,
+ flags | BUF_BUSY);
+ return(bp);
+ }
+
+ /*
+ * 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. In this case we just increment the lock
+ * recursion count and return the buffer to the caller.
+ */
+ if (tp->t_items.lic_next == NULL) {
+ bp = xfs_trans_buf_item_match(tp, target_dev, blkno, len);
+ } else {
+ bp = xfs_trans_buf_item_match_all(tp, target_dev, blkno, len);
+ }
+ if (bp != NULL) {
+ ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
+ if (XFS_FORCED_SHUTDOWN(tp->t_mountp)) {
+ xfs_buftrace("TRANS GET RECUR SHUT", bp);
+ XFS_BUF_SUPER_STALE(bp);
+ }
+ /*
+ * If the buffer is stale then it was binval'ed
+ * since last read. This doesn't matter since the
+ * caller isn't allowed to use the data anyway.
+ */
+ else if (XFS_BUF_ISSTALE(bp)) {
+ xfs_buftrace("TRANS GET RECUR STALE", bp);
+ ASSERT(!XFS_BUF_ISDELAYWRITE(bp));
+ }
+ ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
+ bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
+ ASSERT(bip != NULL);
+ ASSERT(atomic_read(&bip->bli_refcount) > 0);
+ bip->bli_recur++;
+ xfs_buftrace("TRANS GET RECUR", bp);
+ xfs_buf_item_trace("GET RECUR", bip);
+ return (bp);
+ }
+
+ /*
+ * 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.
+ */
+ bp = xfs_buf_get_flags(target_dev, blkno, len, flags | BUF_BUSY);
+ if (bp == NULL) {
+ return NULL;
+ }
+
+ ASSERT(!XFS_BUF_GETERROR(bp));
+
+ /*
+ * 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*);
+ 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 GET", bp);
+ xfs_buf_item_trace("GET", bip);
+ return (bp);
+}
+
+/*
+ * Get and lock the superblock buffer of this file system for the
+ * given transaction.
+ *
+ * We don't need to use incore_match() here, because the superblock
+ * buffer is a private buffer which we keep a pointer to in the
+ * mount structure.
+ */
+xfs_buf_t *
+xfs_trans_getsb(xfs_trans_t *tp,
+ struct xfs_mount *mp,
+ int flags)
+{
+ xfs_buf_t *bp;
+ xfs_buf_log_item_t *bip;
+
+ /*
+ * Default to just trying to lock the superblock buffer
+ * if tp is NULL.
+ */
+ if (tp == NULL) {
+ return (xfs_getsb(mp, flags));
+ }
+
+ /*
+ * If the superblock buffer already has this transaction
+ * pointer in its b_fsprivate2 field, then we know we already
+ * have it locked. In this case we just increment the lock
+ * recursion count and return the buffer to the caller.
+ */
+ bp = mp->m_sb_bp;
+ if (XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp) {
+ bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
+ ASSERT(bip != NULL);
+ ASSERT(atomic_read(&bip->bli_refcount) > 0);
+ bip->bli_recur++;
+ xfs_buf_item_trace("GETSB RECUR", bip);
+ return (bp);
+ }
+
+ bp = xfs_getsb(mp, flags);
+ if (bp == NULL) {
+ return 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, mp);
+
+ /*
+ * Set the recursion count for the buffer within this transaction
+ * to 0.
+ */
+ 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));
+ 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_buf_item_trace("GETSB", bip);
+ return (bp);
+}
+
+#ifdef DEBUG
+xfs_buftarg_t *xfs_error_target;
+int xfs_do_error;
+int xfs_req_num;
+int xfs_error_mod = 33;
+#endif
+
+/*
+ * Get and lock the buffer for the caller if it is not already
+ * locked within the given transaction. If it has not yet been
+ * read in, read it from disk. If it is already locked
+ * within the transaction and already read in, just increment its
+ * lock recursion count and return a pointer to it.
+ *
+ * Use the fast path function xfs_trans_buf_item_match() or the buffer
+ * cache routine incore_match() to find the buffer
+ * if it is already owned by this transaction.
+ *
+ * If we don't already own the buffer, use read_buf() to get it.
+ * If it doesn't yet have an associated xfs_buf_log_item structure,
+ * then allocate one and add the item to this transaction.
+ *
+ * If the transaction pointer is NULL, make this just a normal
+ * read_buf() call.
+ */
+int
+xfs_trans_read_buf(
+ xfs_mount_t *mp,
+ xfs_trans_t *tp,
+ xfs_buftarg_t *target,
+ xfs_daddr_t blkno,
+ int len,
+ uint flags,
+ xfs_buf_t **bpp)
+{
+ xfs_buf_t *bp;
+ xfs_buf_log_item_t *bip;
+ int error;
+
+ if (flags == 0)
+ flags = XFS_BUF_LOCK | XFS_BUF_MAPPED;
+
+ /*
+ * Default to a normal get_buf() call if the tp is NULL.
+ */
+ if (tp == NULL) {
+ bp = xfs_buf_read_flags(target, blkno, len, flags | BUF_BUSY);
+ if (!bp)
+ return XFS_ERROR(ENOMEM);
+
+ if ((bp != NULL) && (XFS_BUF_GETERROR(bp) != 0)) {
+ xfs_ioerror_alert("xfs_trans_read_buf", mp,
+ bp, blkno);
+ error = XFS_BUF_GETERROR(bp);
+ xfs_buf_relse(bp);
+ return error;
+ }
+#ifdef DEBUG
+ if (xfs_do_error && (bp != NULL)) {
+ if (xfs_error_target == target) {
+ if (((xfs_req_num++) % xfs_error_mod) == 0) {
+ xfs_buf_relse(bp);
+ printk("Returning error!\n");
+ return XFS_ERROR(EIO);
+ }
+ }
+ }
+#endif
+ if (XFS_FORCED_SHUTDOWN(mp))
+ goto shutdown_abort;
+ *bpp = bp;
+ return 0;
+ }
+
+ /*
+ * 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
+ * the lock recursion count, and return it to the caller.
+ */
+ if (tp->t_items.lic_next == NULL) {
+ bp = xfs_trans_buf_item_match(tp, target, blkno, len);
+ } else {
+ bp = xfs_trans_buf_item_match_all(tp, target, blkno, len);
+ }
+ if (bp != NULL) {
+ ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
+ ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
+ ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
+ ASSERT((XFS_BUF_ISERROR(bp)) == 0);
+ if (!(XFS_BUF_ISDONE(bp))) {
+ xfs_buftrace("READ_BUF_INCORE !DONE", bp);
+ ASSERT(!XFS_BUF_ISASYNC(bp));
+ XFS_BUF_READ(bp);
+ xfsbdstrat(tp->t_mountp, bp);
+ xfs_iowait(bp);
+ if (XFS_BUF_GETERROR(bp) != 0) {
+ xfs_ioerror_alert("xfs_trans_read_buf", mp,
+ bp, blkno);
+ error = XFS_BUF_GETERROR(bp);
+ xfs_buf_relse(bp);
+ /*
+ * We can gracefully recover from most
+ * read errors. Ones we can't are those
+ * that happen after the transaction's
+ * already dirty.
+ */
+ if (tp->t_flags & XFS_TRANS_DIRTY)
+ xfs_force_shutdown(tp->t_mountp,
+ XFS_METADATA_IO_ERROR);
+ return error;
+ }
+ }
+ /*
+ * We never locked this buf ourselves, so we shouldn't
+ * brelse it either. Just get out.
+ */
+ if (XFS_FORCED_SHUTDOWN(mp)) {
+ xfs_buftrace("READ_BUF_INCORE XFSSHUTDN", bp);
+ *bpp = NULL;
+ return XFS_ERROR(EIO);
+ }
+
+
+ bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
+ bip->bli_recur++;
+
+ ASSERT(atomic_read(&bip->bli_refcount) > 0);
+ xfs_buf_item_trace("READ RECUR", bip);
+ *bpp = bp;
+ return 0;
+ }
+
+ /*
+ * 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.
+ */
+ bp = xfs_buf_read_flags(target, blkno, len, flags | BUF_BUSY);
+ if (bp == NULL) {
+ *bpp = NULL;
+ return 0;
+ }
+ if (XFS_BUF_GETERROR(bp) != 0) {
+ XFS_BUF_SUPER_STALE(bp);
+ xfs_buftrace("READ ERROR", bp);
+ error = XFS_BUF_GETERROR(bp);
+
+ xfs_ioerror_alert("xfs_trans_read_buf", mp,
+ bp, blkno);
+ if (tp->t_flags & XFS_TRANS_DIRTY)
+ xfs_force_shutdown(tp->t_mountp, XFS_METADATA_IO_ERROR);
+ 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,
+ XFS_METADATA_IO_ERROR);
+ xfs_buf_relse(bp);
+ printk("Returning error in trans!\n");
+ 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*);
+ 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);
+}
+
+/*
+ * 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_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;
+}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-24 09:47:40 +0000