xfs: introduce xlog_copy_iovec

[deliverable/linux.git] / fs / xfs / xfs_inode_item.c

/*
 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms 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.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_inode_item.h"
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_trans_priv.h"
#include "xfs_dinode.h"
#include "xfs_log.h"


kmem_zone_t     *xfs_ili_zone;          /* inode log item zone */

static inline struct xfs_inode_log_item *INODE_ITEM(struct xfs_log_item *lip)
{
        return container_of(lip, struct xfs_inode_log_item, ili_item);
}

STATIC void
xfs_inode_item_data_fork_size(
        struct xfs_inode_log_item *iip,
        int                     *nvecs,
        int                     *nbytes)
{
        struct xfs_inode        *ip = iip->ili_inode;

        switch (ip->i_d.di_format) {
        case XFS_DINODE_FMT_EXTENTS:
                if ((iip->ili_fields & XFS_ILOG_DEXT) &&
                    ip->i_d.di_nextents > 0 &&
                    ip->i_df.if_bytes > 0) {
                        /* worst case, doesn't subtract delalloc extents */
                        *nbytes += XFS_IFORK_DSIZE(ip);
                        *nvecs += 1;
                }
                break;
        case XFS_DINODE_FMT_BTREE:
                if ((iip->ili_fields & XFS_ILOG_DBROOT) &&
                    ip->i_df.if_broot_bytes > 0) {
                        *nbytes += ip->i_df.if_broot_bytes;
                        *nvecs += 1;
                }
                break;
        case XFS_DINODE_FMT_LOCAL:
                if ((iip->ili_fields & XFS_ILOG_DDATA) &&
                    ip->i_df.if_bytes > 0) {
                        *nbytes += roundup(ip->i_df.if_bytes, 4);
                        *nvecs += 1;
                }
                break;

        case XFS_DINODE_FMT_DEV:
        case XFS_DINODE_FMT_UUID:
                break;
        default:
                ASSERT(0);
                break;
        }
}

STATIC void
xfs_inode_item_attr_fork_size(
        struct xfs_inode_log_item *iip,
        int                     *nvecs,
        int                     *nbytes)
{
        struct xfs_inode        *ip = iip->ili_inode;

        switch (ip->i_d.di_aformat) {
        case XFS_DINODE_FMT_EXTENTS:
                if ((iip->ili_fields & XFS_ILOG_AEXT) &&
                    ip->i_d.di_anextents > 0 &&
                    ip->i_afp->if_bytes > 0) {
                        /* worst case, doesn't subtract unused space */
                        *nbytes += XFS_IFORK_ASIZE(ip);
                        *nvecs += 1;
                }
                break;
        case XFS_DINODE_FMT_BTREE:
                if ((iip->ili_fields & XFS_ILOG_ABROOT) &&
                    ip->i_afp->if_broot_bytes > 0) {
                        *nbytes += ip->i_afp->if_broot_bytes;
                        *nvecs += 1;
                }
                break;
        case XFS_DINODE_FMT_LOCAL:
                if ((iip->ili_fields & XFS_ILOG_ADATA) &&
                    ip->i_afp->if_bytes > 0) {
                        *nbytes += roundup(ip->i_afp->if_bytes, 4);
                        *nvecs += 1;
                }
                break;
        default:
                ASSERT(0);
                break;
        }
}

/*
 * This returns the number of iovecs needed to log the given inode item.
 *
 * We need one iovec for the inode log format structure, one for the
 * inode core, and possibly one for the inode data/extents/b-tree root
 * and one for the inode attribute data/extents/b-tree root.
 */
STATIC void
xfs_inode_item_size(
        struct xfs_log_item     *lip,
        int                     *nvecs,
        int                     *nbytes)
{
        struct xfs_inode_log_item *iip = INODE_ITEM(lip);
        struct xfs_inode        *ip = iip->ili_inode;

        *nvecs += 2;
        *nbytes += sizeof(struct xfs_inode_log_format) +
                   xfs_icdinode_size(ip->i_d.di_version);

        xfs_inode_item_data_fork_size(iip, nvecs, nbytes);
        if (XFS_IFORK_Q(ip))
                xfs_inode_item_attr_fork_size(iip, nvecs, nbytes);
}

/*
 * xfs_inode_item_format_extents - convert in-core extents to on-disk form
 *
 * For either the data or attr fork in extent format, we need to endian convert
 * the in-core extent as we place them into the on-disk inode. In this case, we
 * need to do this conversion before we write the extents into the log. Because
 * we don't have the disk inode to write into here, we allocate a buffer and
 * format the extents into it via xfs_iextents_copy(). We free the buffer in
 * the unlock routine after the copy for the log has been made.
 *
 * In the case of the data fork, the in-core and on-disk fork sizes can be
 * different due to delayed allocation extents. We only log on-disk extents
 * here, so always use the physical fork size to determine the size of the
 * buffer we need to allocate.
 */
STATIC int
xfs_inode_item_format_extents(
        struct xfs_inode        *ip,
        struct xfs_log_iovec    **vecp,
        int                     whichfork,
        int                     type)
{
        xfs_bmbt_rec_t          *ext_buffer;
        int                     len;

        ext_buffer = kmem_alloc(XFS_IFORK_SIZE(ip, whichfork), KM_SLEEP);
        if (whichfork == XFS_DATA_FORK)
                ip->i_itemp->ili_extents_buf = ext_buffer;
        else
                ip->i_itemp->ili_aextents_buf = ext_buffer;

        len = xfs_iextents_copy(ip, ext_buffer, whichfork);
        xlog_copy_iovec(vecp, type, ext_buffer, len);
        return len;
}

/*
 * If this is a v1 format inode, then we need to log it as such.  This means
 * that we have to copy the link count from the new field to the old.  We
 * don't have to worry about the new fields, because nothing trusts them as
 * long as the old inode version number is there.
 */
STATIC void
xfs_inode_item_format_v1_inode(
        struct xfs_inode        *ip)
{
        if (!xfs_sb_version_hasnlink(&ip->i_mount->m_sb)) {
                /*
                 * Convert it back.
                 */
                ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1);
                ip->i_d.di_onlink = ip->i_d.di_nlink;
        } else {
                /*
                 * The superblock version has already been bumped,
                 * so just make the conversion to the new inode
                 * format permanent.
                 */
                ip->i_d.di_version = 2;
                ip->i_d.di_onlink = 0;
                memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
        }
}

STATIC void
xfs_inode_item_format_data_fork(
        struct xfs_inode_log_item *iip,
        struct xfs_log_iovec    **vecp,
        int                     *nvecs)
{
        struct xfs_inode        *ip = iip->ili_inode;
        size_t                  data_bytes;

        switch (ip->i_d.di_format) {
        case XFS_DINODE_FMT_EXTENTS:
                iip->ili_fields &=
                        ~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
                          XFS_ILOG_DEV | XFS_ILOG_UUID);

                if ((iip->ili_fields & XFS_ILOG_DEXT) &&
                    ip->i_d.di_nextents > 0 &&
                    ip->i_df.if_bytes > 0) {
                        ASSERT(ip->i_df.if_u1.if_extents != NULL);
                        ASSERT(ip->i_df.if_bytes / sizeof(xfs_bmbt_rec_t) > 0);
                        ASSERT(iip->ili_extents_buf == NULL);

#ifdef XFS_NATIVE_HOST
                       if (ip->i_d.di_nextents == ip->i_df.if_bytes /
                                               (uint)sizeof(xfs_bmbt_rec_t)) {
                                /*
                                 * There are no delayed allocation
                                 * extents, so just point to the
                                 * real extents array.
                                 */
                                xlog_copy_iovec(vecp, XLOG_REG_TYPE_IEXT,
                                                ip->i_df.if_u1.if_extents,
                                                ip->i_df.if_bytes);
                                iip->ili_format.ilf_dsize = ip->i_df.if_bytes;
                        } else
#endif
                        {
                                iip->ili_format.ilf_dsize =
                                        xfs_inode_item_format_extents(ip, vecp,
                                                XFS_DATA_FORK, XLOG_REG_TYPE_IEXT);
                                ASSERT(iip->ili_format.ilf_dsize <= ip->i_df.if_bytes);
                        }
                        (*nvecs)++;
                } else {
                        iip->ili_fields &= ~XFS_ILOG_DEXT;
                }
                break;
        case XFS_DINODE_FMT_BTREE:
                iip->ili_fields &=
                        ~(XFS_ILOG_DDATA | XFS_ILOG_DEXT |
                          XFS_ILOG_DEV | XFS_ILOG_UUID);

                if ((iip->ili_fields & XFS_ILOG_DBROOT) &&
                    ip->i_df.if_broot_bytes > 0) {
                        ASSERT(ip->i_df.if_broot != NULL);
                        xlog_copy_iovec(vecp, XLOG_REG_TYPE_IBROOT,
                                        ip->i_df.if_broot,
                                        ip->i_df.if_broot_bytes);
                        (*nvecs)++;
                        iip->ili_format.ilf_dsize = ip->i_df.if_broot_bytes;
                } else {
                        ASSERT(!(iip->ili_fields &
                                 XFS_ILOG_DBROOT));
                        iip->ili_fields &= ~XFS_ILOG_DBROOT;
                }
                break;
        case XFS_DINODE_FMT_LOCAL:
                iip->ili_fields &=
                        ~(XFS_ILOG_DEXT | XFS_ILOG_DBROOT |
                          XFS_ILOG_DEV | XFS_ILOG_UUID);
                if ((iip->ili_fields & XFS_ILOG_DDATA) &&
                    ip->i_df.if_bytes > 0) {
                        /*
                         * Round i_bytes up to a word boundary.
                         * The underlying memory is guaranteed to
                         * to be there by xfs_idata_realloc().
                         */
                        data_bytes = roundup(ip->i_df.if_bytes, 4);
                        ASSERT(ip->i_df.if_real_bytes == 0 ||
                               ip->i_df.if_real_bytes == data_bytes);
                        ASSERT(ip->i_df.if_u1.if_data != NULL);
                        ASSERT(ip->i_d.di_size > 0);
                        xlog_copy_iovec(vecp, XLOG_REG_TYPE_ILOCAL,
                                        ip->i_df.if_u1.if_data, data_bytes);
                        (*nvecs)++;
                        iip->ili_format.ilf_dsize = (unsigned)data_bytes;
                } else {
                        iip->ili_fields &= ~XFS_ILOG_DDATA;
                }
                break;
        case XFS_DINODE_FMT_DEV:
                iip->ili_fields &=
                        ~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
                          XFS_ILOG_DEXT | XFS_ILOG_UUID);
                if (iip->ili_fields & XFS_ILOG_DEV) {
                        iip->ili_format.ilf_u.ilfu_rdev =
                                ip->i_df.if_u2.if_rdev;
                }
                break;
        case XFS_DINODE_FMT_UUID:
                iip->ili_fields &=
                        ~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
                          XFS_ILOG_DEXT | XFS_ILOG_DEV);
                if (iip->ili_fields & XFS_ILOG_UUID) {
                        iip->ili_format.ilf_u.ilfu_uuid =
                                ip->i_df.if_u2.if_uuid;
                }
                break;
        default:
                ASSERT(0);
                break;
        }
}

STATIC void
xfs_inode_item_format_attr_fork(
        struct xfs_inode_log_item *iip,
        struct xfs_log_iovec    **vecp,
        int                     *nvecs)
{
        struct xfs_inode        *ip = iip->ili_inode;
        size_t                  data_bytes;

        switch (ip->i_d.di_aformat) {
        case XFS_DINODE_FMT_EXTENTS:
                iip->ili_fields &=
                        ~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT);

                if ((iip->ili_fields & XFS_ILOG_AEXT) &&
                    ip->i_d.di_anextents > 0 &&
                    ip->i_afp->if_bytes > 0) {
                        ASSERT(ip->i_afp->if_bytes / sizeof(xfs_bmbt_rec_t) ==
                                ip->i_d.di_anextents);
                        ASSERT(ip->i_afp->if_u1.if_extents != NULL);
#ifdef XFS_NATIVE_HOST
                        /*
                         * There are not delayed allocation extents
                         * for attributes, so just point at the array.
                         */
                        xlog_copy_iovec(vecp, XLOG_REG_TYPE_IATTR_EXT,
                                        ip->i_afp->if_u1.if_extents,
                                        ip->i_afp->if_bytes);
                        iip->ili_format.ilf_asize = ip->i_afp->if_bytes;
#else
                        ASSERT(iip->ili_aextents_buf == NULL);
                        iip->ili_format.ilf_asize =
                                xfs_inode_item_format_extents(ip, vecp,
                                        XFS_ATTR_FORK, XLOG_REG_TYPE_IATTR_EXT);
#endif
                        (*nvecs)++;
                } else {
                        iip->ili_fields &= ~XFS_ILOG_AEXT;
                }
                break;
        case XFS_DINODE_FMT_BTREE:
                iip->ili_fields &=
                        ~(XFS_ILOG_ADATA | XFS_ILOG_AEXT);

                if ((iip->ili_fields & XFS_ILOG_ABROOT) &&
                    ip->i_afp->if_broot_bytes > 0) {
                        ASSERT(ip->i_afp->if_broot != NULL);

                        xlog_copy_iovec(vecp, XLOG_REG_TYPE_IATTR_BROOT,
                                        ip->i_afp->if_broot,
                                        ip->i_afp->if_broot_bytes);
                        (*nvecs)++;
                        iip->ili_format.ilf_asize = ip->i_afp->if_broot_bytes;
                } else {
                        iip->ili_fields &= ~XFS_ILOG_ABROOT;
                }
                break;
        case XFS_DINODE_FMT_LOCAL:
                iip->ili_fields &=
                        ~(XFS_ILOG_AEXT | XFS_ILOG_ABROOT);

                if ((iip->ili_fields & XFS_ILOG_ADATA) &&
                    ip->i_afp->if_bytes > 0) {
                        /*
                         * Round i_bytes up to a word boundary.
                         * The underlying memory is guaranteed to
                         * to be there by xfs_idata_realloc().
                         */
                        data_bytes = roundup(ip->i_afp->if_bytes, 4);
                        ASSERT(ip->i_afp->if_real_bytes == 0 ||
                               ip->i_afp->if_real_bytes == data_bytes);
                        ASSERT(ip->i_afp->if_u1.if_data != NULL);
                        xlog_copy_iovec(vecp, XLOG_REG_TYPE_IATTR_LOCAL,
                                        ip->i_afp->if_u1.if_data,
                                        data_bytes);
                        (*nvecs)++;
                        iip->ili_format.ilf_asize = (unsigned)data_bytes;
                } else {
                        iip->ili_fields &= ~XFS_ILOG_ADATA;
                }
                break;
        default:
                ASSERT(0);
                break;
        }
}

/*
 * This is called to fill in the vector of log iovecs for the given inode
 * log item.  It fills the first item with an inode log format structure,
 * the second with the on-disk inode structure, and a possible third and/or
 * fourth with the inode data/extents/b-tree root and inode attributes
 * data/extents/b-tree root.
 */
STATIC void
xfs_inode_item_format(
        struct xfs_log_item     *lip,
        struct xfs_log_iovec    *vecp)
{
        struct xfs_inode_log_item *iip = INODE_ITEM(lip);
        struct xfs_inode        *ip = iip->ili_inode;
        uint                    nvecs;

        xlog_copy_iovec(&vecp, XLOG_REG_TYPE_IFORMAT,
                        &iip->ili_format,
                        sizeof(struct xfs_inode_log_format));
        nvecs = 1;

        xlog_copy_iovec(&vecp, XLOG_REG_TYPE_ICORE,
                        &ip->i_d,
                        xfs_icdinode_size(ip->i_d.di_version));
        nvecs++;

        if (ip->i_d.di_version == 1)
                xfs_inode_item_format_v1_inode(ip);

        xfs_inode_item_format_data_fork(iip, &vecp, &nvecs);
        if (XFS_IFORK_Q(ip)) {
                xfs_inode_item_format_attr_fork(iip, &vecp, &nvecs);
        } else {
                iip->ili_fields &=
                        ~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT | XFS_ILOG_AEXT);
        }

        /*
         * Now update the log format that goes out to disk from the in-core
         * values.  We always write the inode core to make the arithmetic
         * games in recovery easier, which isn't a big deal as just about any
         * transaction would dirty it anyway.
         */
        iip->ili_format.ilf_fields = XFS_ILOG_CORE |
                (iip->ili_fields & ~XFS_ILOG_TIMESTAMP);
        iip->ili_format.ilf_size = nvecs;
}

/*
 * This is called to pin the inode associated with the inode log
 * item in memory so it cannot be written out.
 */
STATIC void
xfs_inode_item_pin(
        struct xfs_log_item     *lip)
{
        struct xfs_inode        *ip = INODE_ITEM(lip)->ili_inode;

        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));

        trace_xfs_inode_pin(ip, _RET_IP_);
        atomic_inc(&ip->i_pincount);
}


/*
 * This is called to unpin the inode associated with the inode log
 * item which was previously pinned with a call to xfs_inode_item_pin().
 *
 * Also wake up anyone in xfs_iunpin_wait() if the count goes to 0.
 */
STATIC void
xfs_inode_item_unpin(
        struct xfs_log_item     *lip,
        int                     remove)
{
        struct xfs_inode        *ip = INODE_ITEM(lip)->ili_inode;

        trace_xfs_inode_unpin(ip, _RET_IP_);
        ASSERT(atomic_read(&ip->i_pincount) > 0);
        if (atomic_dec_and_test(&ip->i_pincount))
                wake_up_bit(&ip->i_flags, __XFS_IPINNED_BIT);
}

STATIC uint
xfs_inode_item_push(
        struct xfs_log_item     *lip,
        struct list_head        *buffer_list)
{
        struct xfs_inode_log_item *iip = INODE_ITEM(lip);
        struct xfs_inode        *ip = iip->ili_inode;
        struct xfs_buf          *bp = NULL;
        uint                    rval = XFS_ITEM_SUCCESS;
        int                     error;

        if (xfs_ipincount(ip) > 0)
                return XFS_ITEM_PINNED;

        if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED))
                return XFS_ITEM_LOCKED;

        /*
         * Re-check the pincount now that we stabilized the value by
         * taking the ilock.
         */
        if (xfs_ipincount(ip) > 0) {
                rval = XFS_ITEM_PINNED;
                goto out_unlock;
        }

        /*
         * Stale inode items should force out the iclog.
         */
        if (ip->i_flags & XFS_ISTALE) {
                rval = XFS_ITEM_PINNED;
                goto out_unlock;
        }

        /*
         * Someone else is already flushing the inode.  Nothing we can do
         * here but wait for the flush to finish and remove the item from
         * the AIL.
         */
        if (!xfs_iflock_nowait(ip)) {
                rval = XFS_ITEM_FLUSHING;
                goto out_unlock;
        }

        ASSERT(iip->ili_fields != 0 || XFS_FORCED_SHUTDOWN(ip->i_mount));
        ASSERT(iip->ili_logged == 0 || XFS_FORCED_SHUTDOWN(ip->i_mount));

        spin_unlock(&lip->li_ailp->xa_lock);

        error = xfs_iflush(ip, &bp);
        if (!error) {
                if (!xfs_buf_delwri_queue(bp, buffer_list))
                        rval = XFS_ITEM_FLUSHING;
                xfs_buf_relse(bp);
        }

        spin_lock(&lip->li_ailp->xa_lock);
out_unlock:
        xfs_iunlock(ip, XFS_ILOCK_SHARED);
        return rval;
}

/*
 * Unlock the inode associated with the inode log item.
 * Clear the fields of the inode and inode log item that
 * are specific to the current transaction.  If the
 * hold flags is set, do not unlock the inode.
 */
STATIC void
xfs_inode_item_unlock(
        struct xfs_log_item     *lip)
{
        struct xfs_inode_log_item *iip = INODE_ITEM(lip);
        struct xfs_inode        *ip = iip->ili_inode;
        unsigned short          lock_flags;

        ASSERT(ip->i_itemp != NULL);
        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));

        /*
         * If the inode needed a separate buffer with which to log
         * its extents, then free it now.
         */
        if (iip->ili_extents_buf != NULL) {
                ASSERT(ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS);
                ASSERT(ip->i_d.di_nextents > 0);
                ASSERT(iip->ili_fields & XFS_ILOG_DEXT);
                ASSERT(ip->i_df.if_bytes > 0);
                kmem_free(iip->ili_extents_buf);
                iip->ili_extents_buf = NULL;
        }
        if (iip->ili_aextents_buf != NULL) {
                ASSERT(ip->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS);
                ASSERT(ip->i_d.di_anextents > 0);
                ASSERT(iip->ili_fields & XFS_ILOG_AEXT);
                ASSERT(ip->i_afp->if_bytes > 0);
                kmem_free(iip->ili_aextents_buf);
                iip->ili_aextents_buf = NULL;
        }

        lock_flags = iip->ili_lock_flags;
        iip->ili_lock_flags = 0;
        if (lock_flags)
                xfs_iunlock(ip, lock_flags);
}

/*
 * This is called to find out where the oldest active copy of the inode log
 * item in the on disk log resides now that the last log write of it completed
 * at the given lsn.  Since we always re-log all dirty data in an inode, the
 * latest copy in the on disk log is the only one that matters.  Therefore,
 * simply return the given lsn.
 *
 * If the inode has been marked stale because the cluster is being freed, we
 * don't want to (re-)insert this inode into the AIL. There is a race condition
 * where the cluster buffer may be unpinned before the inode is inserted into
 * the AIL during transaction committed processing. If the buffer is unpinned
 * before the inode item has been committed and inserted, then it is possible
 * for the buffer to be written and IO completes before the inode is inserted
 * into the AIL. In that case, we'd be inserting a clean, stale inode into the
 * AIL which will never get removed. It will, however, get reclaimed which
 * triggers an assert in xfs_inode_free() complaining about freein an inode
 * still in the AIL.
 *
 * To avoid this, just unpin the inode directly and return a LSN of -1 so the
 * transaction committed code knows that it does not need to do any further
 * processing on the item.
 */
STATIC xfs_lsn_t
xfs_inode_item_committed(
        struct xfs_log_item     *lip,
        xfs_lsn_t               lsn)
{
        struct xfs_inode_log_item *iip = INODE_ITEM(lip);
        struct xfs_inode        *ip = iip->ili_inode;

        if (xfs_iflags_test(ip, XFS_ISTALE)) {
                xfs_inode_item_unpin(lip, 0);
                return -1;
        }
        return lsn;
}

/*
 * XXX rcc - this one really has to do something.  Probably needs
 * to stamp in a new field in the incore inode.
 */
STATIC void
xfs_inode_item_committing(
        struct xfs_log_item     *lip,
        xfs_lsn_t               lsn)
{
        INODE_ITEM(lip)->ili_last_lsn = lsn;
}

/*
 * This is the ops vector shared by all buf log items.
 */
static const struct xfs_item_ops xfs_inode_item_ops = {
        .iop_size       = xfs_inode_item_size,
        .iop_format     = xfs_inode_item_format,
        .iop_pin        = xfs_inode_item_pin,
        .iop_unpin      = xfs_inode_item_unpin,
        .iop_unlock     = xfs_inode_item_unlock,
        .iop_committed  = xfs_inode_item_committed,
        .iop_push       = xfs_inode_item_push,
        .iop_committing = xfs_inode_item_committing
};


/*
 * Initialize the inode log item for a newly allocated (in-core) inode.
 */
void
xfs_inode_item_init(
        struct xfs_inode        *ip,
        struct xfs_mount        *mp)
{
        struct xfs_inode_log_item *iip;

        ASSERT(ip->i_itemp == NULL);
        iip = ip->i_itemp = kmem_zone_zalloc(xfs_ili_zone, KM_SLEEP);

        iip->ili_inode = ip;
        xfs_log_item_init(mp, &iip->ili_item, XFS_LI_INODE,
                                                &xfs_inode_item_ops);
        iip->ili_format.ilf_type = XFS_LI_INODE;
        iip->ili_format.ilf_ino = ip->i_ino;
        iip->ili_format.ilf_blkno = ip->i_imap.im_blkno;
        iip->ili_format.ilf_len = ip->i_imap.im_len;
        iip->ili_format.ilf_boffset = ip->i_imap.im_boffset;
}

/*
 * Free the inode log item and any memory hanging off of it.
 */
void
xfs_inode_item_destroy(
        xfs_inode_t     *ip)
{
        kmem_zone_free(xfs_ili_zone, ip->i_itemp);
}


/*
 * This is the inode flushing I/O completion routine.  It is called
 * from interrupt level when the buffer containing the inode is
 * flushed to disk.  It is responsible for removing the inode item
 * from the AIL if it has not been re-logged, and unlocking the inode's
 * flush lock.
 *
 * To reduce AIL lock traffic as much as possible, we scan the buffer log item
 * list for other inodes that will run this function. We remove them from the
 * buffer list so we can process all the inode IO completions in one AIL lock
 * traversal.
 */
void
xfs_iflush_done(
        struct xfs_buf          *bp,
        struct xfs_log_item     *lip)
{
        struct xfs_inode_log_item *iip;
        struct xfs_log_item     *blip;
        struct xfs_log_item     *next;
        struct xfs_log_item     *prev;
        struct xfs_ail          *ailp = lip->li_ailp;
        int                     need_ail = 0;

        /*
         * Scan the buffer IO completions for other inodes being completed and
         * attach them to the current inode log item.
         */
        blip = bp->b_fspriv;
        prev = NULL;
        while (blip != NULL) {
                if (lip->li_cb != xfs_iflush_done) {
                        prev = blip;
                        blip = blip->li_bio_list;
                        continue;
                }

                /* remove from list */
                next = blip->li_bio_list;
                if (!prev) {
                        bp->b_fspriv = next;
                } else {
                        prev->li_bio_list = next;
                }

                /* add to current list */
                blip->li_bio_list = lip->li_bio_list;
                lip->li_bio_list = blip;

                /*
                 * while we have the item, do the unlocked check for needing
                 * the AIL lock.
                 */
                iip = INODE_ITEM(blip);
                if (iip->ili_logged && blip->li_lsn == iip->ili_flush_lsn)
                        need_ail++;

                blip = next;
        }

        /* make sure we capture the state of the initial inode. */
        iip = INODE_ITEM(lip);
        if (iip->ili_logged && lip->li_lsn == iip->ili_flush_lsn)
                need_ail++;

        /*
         * We only want to pull the item from the AIL if it is
         * actually there and its location in the log has not
         * changed since we started the flush.  Thus, we only bother
         * if the ili_logged flag is set and the inode's lsn has not
         * changed.  First we check the lsn outside
         * the lock since it's cheaper, and then we recheck while
         * holding the lock before removing the inode from the AIL.
         */
        if (need_ail) {
                struct xfs_log_item *log_items[need_ail];
                int i = 0;
                spin_lock(&ailp->xa_lock);
                for (blip = lip; blip; blip = blip->li_bio_list) {
                        iip = INODE_ITEM(blip);
                        if (iip->ili_logged &&
                            blip->li_lsn == iip->ili_flush_lsn) {
                                log_items[i++] = blip;
                        }
                        ASSERT(i <= need_ail);
                }
                /* xfs_trans_ail_delete_bulk() drops the AIL lock. */
                xfs_trans_ail_delete_bulk(ailp, log_items, i,
                                          SHUTDOWN_CORRUPT_INCORE);
        }


        /*
         * clean up and unlock the flush lock now we are done. We can clear the
         * ili_last_fields bits now that we know that the data corresponding to
         * them is safely on disk.
         */
        for (blip = lip; blip; blip = next) {
                next = blip->li_bio_list;
                blip->li_bio_list = NULL;

                iip = INODE_ITEM(blip);
                iip->ili_logged = 0;
                iip->ili_last_fields = 0;
                xfs_ifunlock(iip->ili_inode);
        }
}

/*
 * This is the inode flushing abort routine.  It is called from xfs_iflush when
 * the filesystem is shutting down to clean up the inode state.  It is
 * responsible for removing the inode item from the AIL if it has not been
 * re-logged, and unlocking the inode's flush lock.
 */
void
xfs_iflush_abort(
        xfs_inode_t             *ip,
        bool                    stale)
{
        xfs_inode_log_item_t    *iip = ip->i_itemp;

        if (iip) {
                struct xfs_ail  *ailp = iip->ili_item.li_ailp;
                if (iip->ili_item.li_flags & XFS_LI_IN_AIL) {
                        spin_lock(&ailp->xa_lock);
                        if (iip->ili_item.li_flags & XFS_LI_IN_AIL) {
                                /* xfs_trans_ail_delete() drops the AIL lock. */
                                xfs_trans_ail_delete(ailp, &iip->ili_item,
                                                stale ?
                                                     SHUTDOWN_LOG_IO_ERROR :
                                                     SHUTDOWN_CORRUPT_INCORE);
                        } else
                                spin_unlock(&ailp->xa_lock);
                }
                iip->ili_logged = 0;
                /*
                 * Clear the ili_last_fields bits now that we know that the
                 * data corresponding to them is safely on disk.
                 */
                iip->ili_last_fields = 0;
                /*
                 * Clear the inode logging fields so no more flushes are
                 * attempted.
                 */
                iip->ili_fields = 0;
        }
        /*
         * Release the inode's flush lock since we're done with it.
         */
        xfs_ifunlock(ip);
}

void
xfs_istale_done(
        struct xfs_buf          *bp,
        struct xfs_log_item     *lip)
{
        xfs_iflush_abort(INODE_ITEM(lip)->ili_inode, true);
}

/*
 * convert an xfs_inode_log_format struct from either 32 or 64 bit versions
 * (which can have different field alignments) to the native version
 */
int
xfs_inode_item_format_convert(
        xfs_log_iovec_t         *buf,
        xfs_inode_log_format_t  *in_f)
{
        if (buf->i_len == sizeof(xfs_inode_log_format_32_t)) {
                xfs_inode_log_format_32_t *in_f32 = buf->i_addr;

                in_f->ilf_type = in_f32->ilf_type;
                in_f->ilf_size = in_f32->ilf_size;
                in_f->ilf_fields = in_f32->ilf_fields;
                in_f->ilf_asize = in_f32->ilf_asize;
                in_f->ilf_dsize = in_f32->ilf_dsize;
                in_f->ilf_ino = in_f32->ilf_ino;
                /* copy biggest field of ilf_u */
                memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
                       in_f32->ilf_u.ilfu_uuid.__u_bits,
                       sizeof(uuid_t));
                in_f->ilf_blkno = in_f32->ilf_blkno;
                in_f->ilf_len = in_f32->ilf_len;
                in_f->ilf_boffset = in_f32->ilf_boffset;
                return 0;
        } else if (buf->i_len == sizeof(xfs_inode_log_format_64_t)){
                xfs_inode_log_format_64_t *in_f64 = buf->i_addr;

                in_f->ilf_type = in_f64->ilf_type;
                in_f->ilf_size = in_f64->ilf_size;
                in_f->ilf_fields = in_f64->ilf_fields;
                in_f->ilf_asize = in_f64->ilf_asize;
                in_f->ilf_dsize = in_f64->ilf_dsize;
                in_f->ilf_ino = in_f64->ilf_ino;
                /* copy biggest field of ilf_u */
                memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
                       in_f64->ilf_u.ilfu_uuid.__u_bits,
                       sizeof(uuid_t));
                in_f->ilf_blkno = in_f64->ilf_blkno;
                in_f->ilf_len = in_f64->ilf_len;
                in_f->ilf_boffset = in_f64->ilf_boffset;
                return 0;
        }
        return EFSCORRUPTED;
}