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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *   Copyright (C) International Business Machines Corp., 2000-2004
  */
 
 /*
  *  jfs_imap.c: inode allocation map manager
  *
  * Serialization:
  *   Each AG has a simple lock which is used to control the serialization of
  *  the AG level lists.  This lock should be taken first whenever an AG
  *  level list will be modified or accessed.
  *
  *   Each IAG is locked by obtaining the buffer for the IAG page.
  *
  *   There is also a inode lock for the inode map inode.  A read lock needs to
  *  be taken whenever an IAG is read from the map or the global level
  *  information is read.  A write lock needs to be taken whenever the global
  *  level information is modified or an atomic operation needs to be used.
  *
  *  If more than one IAG is read at one time, the read lock may not
  *  be given up until all of the IAG's are read.  Otherwise, a deadlock
  *  may occur when trying to obtain the read lock while another thread
  *  holding the read lock is waiting on the IAG already being held.
  *
  *   The control page of the inode map is read into memory by diMount().
  *  Thereafter it should only be modified in memory and then it will be
  *  written out when the filesystem is unmounted by diUnmount().
  */
 
 #include <linux/fs.h>
 #include <linux/buffer_head.h>
 #include <linux/pagemap.h>
 #include <linux/quotaops.h>
 #include <linux/slab.h>
 
 #include "jfs_incore.h"
 #include "jfs_inode.h"
 #include "jfs_filsys.h"
 #include "jfs_dinode.h"
 #include "jfs_dmap.h"
 #include "jfs_imap.h"
 #include "jfs_metapage.h"
 #include "jfs_superblock.h"
 #include "jfs_debug.h"
 
 /*
  * imap locks
  */
 /* iag free list lock */
 #define IAGFREE_LOCK_INIT(imap)     mutex_init(&imap->im_freelock)
 #define IAGFREE_LOCK(imap)      mutex_lock(&imap->im_freelock)
 #define IAGFREE_UNLOCK(imap)        mutex_unlock(&imap->im_freelock)
 
 /* per ag iag list locks */
 #define AG_LOCK_INIT(imap,index)    mutex_init(&(imap->im_aglock[index]))
 #define AG_LOCK(imap,agno)      mutex_lock(&imap->im_aglock[agno])
 #define AG_UNLOCK(imap,agno)        mutex_unlock(&imap->im_aglock[agno])
 
 /*
  * forward references
  */
 static int diAllocAG(struct inomap *, int, bool, struct inode *);
 static int diAllocAny(struct inomap *, int, bool, struct inode *);
 static int diAllocBit(struct inomap *, struct iag *, int);
 static int diAllocExt(struct inomap *, int, struct inode *);
 static int diAllocIno(struct inomap *, int, struct inode *);
 static int diFindFree(u32, int);
 static int diNewExt(struct inomap *, struct iag *, int);
 static int diNewIAG(struct inomap *, int *, int, struct metapage **);
 static void duplicateIXtree(struct super_block *, s64, int, s64 *);
 
 static int diIAGRead(struct inomap * imap, int, struct metapage **);
 static int copy_from_dinode(struct dinode *, struct inode *);
 static void copy_to_dinode(struct dinode *, struct inode *);
 
 /*
  * NAME:    diMount()
  *
  * FUNCTION:    initialize the incore inode map control structures for
  *      a fileset or aggregate init time.
  *
  *      the inode map's control structure (dinomap) is
  *      brought in from disk and placed in virtual memory.
  *
  * PARAMETERS:
  *  ipimap  - pointer to inode map inode for the aggregate or fileset.
  *
  * RETURN VALUES:
  *  0   - success
  *  -ENOMEM - insufficient free virtual memory.
  *  -EIO    - i/o error.
  */
 int diMount(struct inode *ipimap)
 {
     struct inomap *imap;
     struct metapage *mp;
     int index;
     struct dinomap_disk *dinom_le;
 
     /*
      * allocate/initialize the in-memory inode map control structure
      */
     /* allocate the in-memory inode map control structure. */
     imap = kmalloc(sizeof(struct inomap), GFP_KERNEL);
     if (imap == NULL)
         return -ENOMEM;
 
     /* read the on-disk inode map control structure. */
 
     mp = read_metapage(ipimap,
                IMAPBLKNO << JFS_SBI(ipimap->i_sb)->l2nbperpage,
                PSIZE, 0);
     if (mp == NULL) {
         kfree(imap);
         return -EIO;
     }
 
     /* copy the on-disk version to the in-memory version. */
     dinom_le = (struct dinomap_disk *) mp->data;
     imap->im_freeiag = le32_to_cpu(dinom_le->in_freeiag);
     imap->im_nextiag = le32_to_cpu(dinom_le->in_nextiag);
     atomic_set(&imap->im_numinos, le32_to_cpu(dinom_le->in_numinos));
     atomic_set(&imap->im_numfree, le32_to_cpu(dinom_le->in_numfree));
     imap->im_nbperiext = le32_to_cpu(dinom_le->in_nbperiext);
     imap->im_l2nbperiext = le32_to_cpu(dinom_le->in_l2nbperiext);
     for (index = 0; index < MAXAG; index++) {
         imap->im_agctl[index].inofree =
             le32_to_cpu(dinom_le->in_agctl[index].inofree);
         imap->im_agctl[index].extfree =
             le32_to_cpu(dinom_le->in_agctl[index].extfree);
         imap->im_agctl[index].numinos =
             le32_to_cpu(dinom_le->in_agctl[index].numinos);
         imap->im_agctl[index].numfree =
             le32_to_cpu(dinom_le->in_agctl[index].numfree);
     }
 
     /* release the buffer. */
     release_metapage(mp);
 
     /*
      * allocate/initialize inode allocation map locks
      */
     /* allocate and init iag free list lock */
     IAGFREE_LOCK_INIT(imap);
 
     /* allocate and init ag list locks */
     for (index = 0; index < MAXAG; index++) {
         AG_LOCK_INIT(imap, index);
     }
 
     /* bind the inode map inode and inode map control structure
      * to each other.
      */
     imap->im_ipimap = ipimap;
     JFS_IP(ipimap)->i_imap = imap;
 
     return (0);
 }
 
 
 /*
  * NAME:    diUnmount()
  *
  * FUNCTION:    write to disk the incore inode map control structures for
  *      a fileset or aggregate at unmount time.
  *
  * PARAMETERS:
  *  ipimap  - pointer to inode map inode for the aggregate or fileset.
  *
  * RETURN VALUES:
  *  0   - success
  *  -ENOMEM - insufficient free virtual memory.
  *  -EIO    - i/o error.
  */
 int diUnmount(struct inode *ipimap, int mounterror)
 {
     struct inomap *imap = JFS_IP(ipimap)->i_imap;
 
     /*
      * update the on-disk inode map control structure
      */
 
     if (!(mounterror || isReadOnly(ipimap)))
         diSync(ipimap);
 
     /*
      * Invalidate the page cache buffers
      */
     truncate_inode_pages(ipimap->i_mapping, 0);
 
     /*
      * free in-memory control structure
      */
     kfree(imap);
 
     return (0);
 }
 
 
 /*
  *  diSync()
  */
 int diSync(struct inode *ipimap)
 {
     struct dinomap_disk *dinom_le;
     struct inomap *imp = JFS_IP(ipimap)->i_imap;
     struct metapage *mp;
     int index;
 
     /*
      * write imap global conrol page
      */
     /* read the on-disk inode map control structure */
     mp = get_metapage(ipimap,
               IMAPBLKNO << JFS_SBI(ipimap->i_sb)->l2nbperpage,
               PSIZE, 0);
     if (mp == NULL) {
         jfs_err("diSync: get_metapage failed!");
         return -EIO;
     }
 
     /* copy the in-memory version to the on-disk version */
     dinom_le = (struct dinomap_disk *) mp->data;
     dinom_le->in_freeiag = cpu_to_le32(imp->im_freeiag);
     dinom_le->in_nextiag = cpu_to_le32(imp->im_nextiag);
     dinom_le->in_numinos = cpu_to_le32(atomic_read(&imp->im_numinos));
     dinom_le->in_numfree = cpu_to_le32(atomic_read(&imp->im_numfree));
     dinom_le->in_nbperiext = cpu_to_le32(imp->im_nbperiext);
     dinom_le->in_l2nbperiext = cpu_to_le32(imp->im_l2nbperiext);
     for (index = 0; index < MAXAG; index++) {
         dinom_le->in_agctl[index].inofree =
             cpu_to_le32(imp->im_agctl[index].inofree);
         dinom_le->in_agctl[index].extfree =
             cpu_to_le32(imp->im_agctl[index].extfree);
         dinom_le->in_agctl[index].numinos =
             cpu_to_le32(imp->im_agctl[index].numinos);
         dinom_le->in_agctl[index].numfree =
             cpu_to_le32(imp->im_agctl[index].numfree);
     }
 
     /* write out the control structure */
     write_metapage(mp);
 
     /*
      * write out dirty pages of imap
      */
     filemap_write_and_wait(ipimap->i_mapping);
 
     diWriteSpecial(ipimap, 0);
 
     return (0);
 }
 
 
 /*
  * NAME:    diRead()
  *
  * FUNCTION:    initialize an incore inode from disk.
  *
  *      on entry, the specifed incore inode should itself
  *      specify the disk inode number corresponding to the
  *      incore inode (i.e. i_number should be initialized).
  *
  *      this routine handles incore inode initialization for
  *      both "special" and "regular" inodes.  special inodes
  *      are those required early in the mount process and
  *      require special handling since much of the file system
  *      is not yet initialized.  these "special" inodes are
  *      identified by a NULL inode map inode pointer and are
  *      actually initialized by a call to diReadSpecial().
  *
  *      for regular inodes, the iag describing the disk inode
  *      is read from disk to determine the inode extent address
  *      for the disk inode.  with the inode extent address in
  *      hand, the page of the extent that contains the disk
  *      inode is read and the disk inode is copied to the
  *      incore inode.
  *
  * PARAMETERS:
  *  ip  -  pointer to incore inode to be initialized from disk.
  *
  * RETURN VALUES:
  *  0   - success
  *  -EIO    - i/o error.
  *  -ENOMEM - insufficient memory
  *
  */
 int diRead(struct inode *ip)
 {
     struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
     int iagno, ino, extno, rc;
     struct inode *ipimap;
     struct dinode *dp;
     struct iag *iagp;
     struct metapage *mp;
     s64 blkno, agstart;
     struct inomap *imap;
     int block_offset;
     int inodes_left;
     unsigned long pageno;
     int rel_inode;
 
     jfs_info("diRead: ino = %ld", ip->i_ino);
 
     ipimap = sbi->ipimap;
     JFS_IP(ip)->ipimap = ipimap;
 
     /* determine the iag number for this inode (number) */
     iagno = INOTOIAG(ip->i_ino);
 
     /* read the iag */
     imap = JFS_IP(ipimap)->i_imap;
     IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
     rc = diIAGRead(imap, iagno, &mp);
     IREAD_UNLOCK(ipimap);
     if (rc) {
         jfs_err("diRead: diIAGRead returned %d", rc);
         return (rc);
     }
 
     iagp = (struct iag *) mp->data;
 
     /* determine inode extent that holds the disk inode */
     ino = ip->i_ino & (INOSPERIAG - 1);
     extno = ino >> L2INOSPEREXT;
 
     if ((lengthPXD(&iagp->inoext[extno]) != imap->im_nbperiext) ||
         (addressPXD(&iagp->inoext[extno]) == 0)) {
         release_metapage(mp);
         return -ESTALE;
     }
 
     /* get disk block number of the page within the inode extent
      * that holds the disk inode.
      */
     blkno = INOPBLK(&iagp->inoext[extno], ino, sbi->l2nbperpage);
 
     /* get the ag for the iag */
     agstart = le64_to_cpu(iagp->agstart);
 
     release_metapage(mp);
 
     rel_inode = (ino & (INOSPERPAGE - 1));
     pageno = blkno >> sbi->l2nbperpage;
 
     if ((block_offset = ((u32) blkno & (sbi->nbperpage - 1)))) {
         /*
          * OS/2 didn't always align inode extents on page boundaries
          */
         inodes_left =
              (sbi->nbperpage - block_offset) << sbi->l2niperblk;
 
         if (rel_inode < inodes_left)
             rel_inode += block_offset << sbi->l2niperblk;
         else {
             pageno += 1;
             rel_inode -= inodes_left;
         }
     }
 
     /* read the page of disk inode */
     mp = read_metapage(ipimap, pageno << sbi->l2nbperpage, PSIZE, 1);
     if (!mp) {
         jfs_err("diRead: read_metapage failed");
         return -EIO;
     }
 
     /* locate the disk inode requested */
     dp = (struct dinode *) mp->data;
     dp += rel_inode;
 
     if (ip->i_ino != le32_to_cpu(dp->di_number)) {
         jfs_error(ip->i_sb, "i_ino != di_number\n");
         rc = -EIO;
     } else if (le32_to_cpu(dp->di_nlink) == 0)
         rc = -ESTALE;
     else
         /* copy the disk inode to the in-memory inode */
         rc = copy_from_dinode(dp, ip);
 
     release_metapage(mp);
 
     /* set the ag for the inode */
     JFS_IP(ip)->agstart = agstart;
     JFS_IP(ip)->active_ag = -1;
 
     return (rc);
 }
 
 
 /*
  * NAME:    diReadSpecial()
  *
  * FUNCTION:    initialize a 'special' inode from disk.
  *
  *      this routines handles aggregate level inodes.  The
  *      inode cache cannot differentiate between the
  *      aggregate inodes and the filesystem inodes, so we
  *      handle these here.  We don't actually use the aggregate
  *      inode map, since these inodes are at a fixed location
  *      and in some cases the aggregate inode map isn't initialized
  *      yet.
  *
  * PARAMETERS:
  *  sb - filesystem superblock
  *  inum - aggregate inode number
  *  secondary - 1 if secondary aggregate inode table
  *
  * RETURN VALUES:
  *  new inode   - success
  *  NULL        - i/o error.
  */
 struct inode *diReadSpecial(struct super_block *sb, ino_t inum, int secondary)
 {
     struct jfs_sb_info *sbi = JFS_SBI(sb);
     uint address;
     struct dinode *dp;
     struct inode *ip;
     struct metapage *mp;
 
     ip = new_inode(sb);
     if (ip == NULL) {
         jfs_err("diReadSpecial: new_inode returned NULL!");
         return ip;
     }
 
     if (secondary) {
         address = addressPXD(&sbi->ait2) >> sbi->l2nbperpage;
         JFS_IP(ip)->ipimap = sbi->ipaimap2;
     } else {
         address = AITBL_OFF >> L2PSIZE;
         JFS_IP(ip)->ipimap = sbi->ipaimap;
     }
 
     ASSERT(inum < INOSPEREXT);
 
     ip->i_ino = inum;
 
     address += inum >> 3;   /* 8 inodes per 4K page */
 
     /* read the page of fixed disk inode (AIT) in raw mode */
     mp = read_metapage(ip, address << sbi->l2nbperpage, PSIZE, 1);
     if (mp == NULL) {
         set_nlink(ip, 1);   /* Don't want iput() deleting it */
         iput(ip);
         return (NULL);
     }
 
     /* get the pointer to the disk inode of interest */
     dp = (struct dinode *) (mp->data);
     dp += inum % 8;     /* 8 inodes per 4K page */
 
     /* copy on-disk inode to in-memory inode */
     if ((copy_from_dinode(dp, ip)) != 0) {
         /* handle bad return by returning NULL for ip */
         set_nlink(ip, 1);   /* Don't want iput() deleting it */
         iput(ip);
         /* release the page */
         release_metapage(mp);
         return (NULL);
 
     }
 
     ip->i_mapping->a_ops = &jfs_metapage_aops;
     mapping_set_gfp_mask(ip->i_mapping, GFP_NOFS);
 
     /* Allocations to metadata inodes should not affect quotas */
     ip->i_flags |= S_NOQUOTA;
 
     if ((inum == FILESYSTEM_I) && (JFS_IP(ip)->ipimap == sbi->ipaimap)) {
         sbi->gengen = le32_to_cpu(dp->di_gengen);
         sbi->inostamp = le32_to_cpu(dp->di_inostamp);
     }
 
     /* release the page */
     release_metapage(mp);
 
     inode_fake_hash(ip);
 
     return (ip);
 }
 
 /*
  * NAME:    diWriteSpecial()
  *
  * FUNCTION:    Write the special inode to disk
  *
  * PARAMETERS:
  *  ip - special inode
  *  secondary - 1 if secondary aggregate inode table
  *
  * RETURN VALUES: none
  */
 
 void diWriteSpecial(struct inode *ip, int secondary)
 {
     struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
     uint address;
     struct dinode *dp;
     ino_t inum = ip->i_ino;
     struct metapage *mp;
 
     if (secondary)
         address = addressPXD(&sbi->ait2) >> sbi->l2nbperpage;
     else
         address = AITBL_OFF >> L2PSIZE;
 
     ASSERT(inum < INOSPEREXT);
 
     address += inum >> 3;   /* 8 inodes per 4K page */
 
     /* read the page of fixed disk inode (AIT) in raw mode */
     mp = read_metapage(ip, address << sbi->l2nbperpage, PSIZE, 1);
     if (mp == NULL) {
         jfs_err("diWriteSpecial: failed to read aggregate inode extent!");
         return;
     }
 
     /* get the pointer to the disk inode of interest */
     dp = (struct dinode *) (mp->data);
     dp += inum % 8;     /* 8 inodes per 4K page */
 
     /* copy on-disk inode to in-memory inode */
     copy_to_dinode(dp, ip);
     memcpy(&dp->di_xtroot, &JFS_IP(ip)->i_xtroot, 288);
 
     if (inum == FILESYSTEM_I)
         dp->di_gengen = cpu_to_le32(sbi->gengen);
 
     /* write the page */
     write_metapage(mp);
 }
 
 /*
  * NAME:    diFreeSpecial()
  *
  * FUNCTION:    Free allocated space for special inode
  */
 void diFreeSpecial(struct inode *ip)
 {
     if (ip == NULL) {
         jfs_err("diFreeSpecial called with NULL ip!");
         return;
     }
     filemap_write_and_wait(ip->i_mapping);
     truncate_inode_pages(ip->i_mapping, 0);
     iput(ip);
 }
 
 
 
 /*
  * NAME:    diWrite()
  *
  * FUNCTION:    write the on-disk inode portion of the in-memory inode
  *      to its corresponding on-disk inode.
  *
  *      on entry, the specifed incore inode should itself
  *      specify the disk inode number corresponding to the
  *      incore inode (i.e. i_number should be initialized).
  *
  *      the inode contains the inode extent address for the disk
  *      inode.  with the inode extent address in hand, the
  *      page of the extent that contains the disk inode is
  *      read and the disk inode portion of the incore inode
  *      is copied to the disk inode.
  *
  * PARAMETERS:
  *  tid -  transacation id
  *  ip  -  pointer to incore inode to be written to the inode extent.
  *
  * RETURN VALUES:
  *  0   - success
  *  -EIO    - i/o error.
  */
 int diWrite(tid_t tid, struct inode *ip)
 {
     struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
     struct jfs_inode_info *jfs_ip = JFS_IP(ip);
     int rc = 0;
     s32 ino;
     struct dinode *dp;
     s64 blkno;
     int block_offset;
     int inodes_left;
     struct metapage *mp;
     unsigned long pageno;
     int rel_inode;
     int dioffset;
     struct inode *ipimap;
     uint type;
     lid_t lid;
     struct tlock *ditlck, *tlck;
     struct linelock *dilinelock, *ilinelock;
     struct lv *lv;
     int n;
 
     ipimap = jfs_ip->ipimap;
 
     ino = ip->i_ino & (INOSPERIAG - 1);
 
     if (!addressPXD(&(jfs_ip->ixpxd)) ||
         (lengthPXD(&(jfs_ip->ixpxd)) !=
          JFS_IP(ipimap)->i_imap->im_nbperiext)) {
         jfs_error(ip->i_sb, "ixpxd invalid\n");
         return -EIO;
     }
 
     /*
      * read the page of disk inode containing the specified inode:
      */
     /* compute the block address of the page */
     blkno = INOPBLK(&(jfs_ip->ixpxd), ino, sbi->l2nbperpage);
 
     rel_inode = (ino & (INOSPERPAGE - 1));
     pageno = blkno >> sbi->l2nbperpage;
 
     if ((block_offset = ((u32) blkno & (sbi->nbperpage - 1)))) {
         /*
          * OS/2 didn't always align inode extents on page boundaries
          */
         inodes_left =
             (sbi->nbperpage - block_offset) << sbi->l2niperblk;
 
         if (rel_inode < inodes_left)
             rel_inode += block_offset << sbi->l2niperblk;
         else {
             pageno += 1;
             rel_inode -= inodes_left;
         }
     }
     /* read the page of disk inode */
       retry:
     mp = read_metapage(ipimap, pageno << sbi->l2nbperpage, PSIZE, 1);
     if (!mp)
         return -EIO;
 
     /* get the pointer to the disk inode */
     dp = (struct dinode *) mp->data;
     dp += rel_inode;
 
     dioffset = (ino & (INOSPERPAGE - 1)) << L2DISIZE;
 
     /*
      * acquire transaction lock on the on-disk inode;
      * N.B. tlock is acquired on ipimap not ip;
      */
     if ((ditlck =
          txLock(tid, ipimap, mp, tlckINODE | tlckENTRY)) == NULL)
         goto retry;
     dilinelock = (struct linelock *) & ditlck->lock;
 
     /*
      * copy btree root from in-memory inode to on-disk inode
      *
      * (tlock is taken from inline B+-tree root in in-memory
      * inode when the B+-tree root is updated, which is pointed
      * by jfs_ip->blid as well as being on tx tlock list)
      *
      * further processing of btree root is based on the copy
      * in in-memory inode, where txLog() will log from, and,
      * for xtree root, txUpdateMap() will update map and reset
      * XAD_NEW bit;
      */
 
     if (S_ISDIR(ip->i_mode) && (lid = jfs_ip->xtlid)) {
         /*
          * This is the special xtree inside the directory for storing
          * the directory table
          */
         xtpage_t *p, *xp;
         xad_t *xad;
 
         jfs_ip->xtlid = 0;
         tlck = lid_to_tlock(lid);
         assert(tlck->type & tlckXTREE);
         tlck->type |= tlckBTROOT;
         tlck->mp = mp;
         ilinelock = (struct linelock *) & tlck->lock;
 
         /*
          * copy xtree root from inode to dinode:
          */
         p = &jfs_ip->i_xtroot;
         xp = (xtpage_t *) &dp->di_dirtable;
         lv = ilinelock->lv;
         for (n = 0; n < ilinelock->index; n++, lv++) {
             memcpy(&xp->xad[lv->offset], &p->xad[lv->offset],
                    lv->length << L2XTSLOTSIZE);
         }
 
         /* reset on-disk (metadata page) xtree XAD_NEW bit */
         xad = &xp->xad[XTENTRYSTART];
         for (n = XTENTRYSTART;
              n < le16_to_cpu(xp->header.nextindex); n++, xad++)
             if (xad->flag & (XAD_NEW | XAD_EXTENDED))
                 xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
     }
 
     if ((lid = jfs_ip->blid) == 0)
         goto inlineData;
     jfs_ip->blid = 0;
 
     tlck = lid_to_tlock(lid);
     type = tlck->type;
     tlck->type |= tlckBTROOT;
     tlck->mp = mp;
     ilinelock = (struct linelock *) & tlck->lock;
 
     /*
      *  regular file: 16 byte (XAD slot) granularity
      */
     if (type & tlckXTREE) {
         xtpage_t *p, *xp;
         xad_t *xad;
 
         /*
          * copy xtree root from inode to dinode:
          */
         p = &jfs_ip->i_xtroot;
         xp = &dp->di_xtroot;
         lv = ilinelock->lv;
         for (n = 0; n < ilinelock->index; n++, lv++) {
             memcpy(&xp->xad[lv->offset], &p->xad[lv->offset],
                    lv->length << L2XTSLOTSIZE);
         }
 
         /* reset on-disk (metadata page) xtree XAD_NEW bit */
         xad = &xp->xad[XTENTRYSTART];
         for (n = XTENTRYSTART;
              n < le16_to_cpu(xp->header.nextindex); n++, xad++)
             if (xad->flag & (XAD_NEW | XAD_EXTENDED))
                 xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
     }
     /*
      *  directory: 32 byte (directory entry slot) granularity
      */
     else if (type & tlckDTREE) {
         dtpage_t *p, *xp;
 
         /*
          * copy dtree root from inode to dinode:
          */
         p = (dtpage_t *) &jfs_ip->i_dtroot;
         xp = (dtpage_t *) & dp->di_dtroot;
         lv = ilinelock->lv;
         for (n = 0; n < ilinelock->index; n++, lv++) {
             memcpy(&xp->slot[lv->offset], &p->slot[lv->offset],
                    lv->length << L2DTSLOTSIZE);
         }
     } else {
         jfs_err("diWrite: UFO tlock");
     }
 
       inlineData:
     /*
      * copy inline symlink from in-memory inode to on-disk inode
      */
     if (S_ISLNK(ip->i_mode) && ip->i_size < IDATASIZE) {
         lv = & dilinelock->lv[dilinelock->index];
         lv->offset = (dioffset + 2 * 128) >> L2INODESLOTSIZE;
         lv->length = 2;
         memcpy(&dp->di_inline_all, jfs_ip->i_inline_all, IDATASIZE);
         dilinelock->index++;
     }
     /*
      * copy inline data from in-memory inode to on-disk inode:
      * 128 byte slot granularity
      */
     if (test_cflag(COMMIT_Inlineea, ip)) {
         lv = & dilinelock->lv[dilinelock->index];
         lv->offset = (dioffset + 3 * 128) >> L2INODESLOTSIZE;
         lv->length = 1;
         memcpy(&dp->di_inlineea, jfs_ip->i_inline_ea, INODESLOTSIZE);
         dilinelock->index++;
 
         clear_cflag(COMMIT_Inlineea, ip);
     }
 
     /*
      *  lock/copy inode base: 128 byte slot granularity
      */
     lv = & dilinelock->lv[dilinelock->index];
     lv->offset = dioffset >> L2INODESLOTSIZE;
     copy_to_dinode(dp, ip);
     if (test_and_clear_cflag(COMMIT_Dirtable, ip)) {
         lv->length = 2;
         memcpy(&dp->di_dirtable, &jfs_ip->i_dirtable, 96);
     } else
         lv->length = 1;
     dilinelock->index++;
 
     /* release the buffer holding the updated on-disk inode.
      * the buffer will be later written by commit processing.
      */
     write_metapage(mp);
 
     return (rc);
 }
 
 
 /*
  * NAME:    diFree(ip)
  *
  * FUNCTION:    free a specified inode from the inode working map
  *      for a fileset or aggregate.
  *
  *      if the inode to be freed represents the first (only)
  *      free inode within the iag, the iag will be placed on
  *      the ag free inode list.
  *
  *      freeing the inode will cause the inode extent to be
  *      freed if the inode is the only allocated inode within
  *      the extent.  in this case all the disk resource backing
  *      up the inode extent will be freed. in addition, the iag
  *      will be placed on the ag extent free list if the extent
  *      is the first free extent in the iag.  if freeing the
  *      extent also means that no free inodes will exist for
  *      the iag, the iag will also be removed from the ag free
  *      inode list.
  *
  *      the iag describing the inode will be freed if the extent
  *      is to be freed and it is the only backed extent within
  *      the iag.  in this case, the iag will be removed from the
  *      ag free extent list and ag free inode list and placed on
  *      the inode map's free iag list.
  *
  *      a careful update approach is used to provide consistency
  *      in the face of updates to multiple buffers.  under this
  *      approach, all required buffers are obtained before making
  *      any updates and are held until all updates are complete.
  *
  * PARAMETERS:
  *  ip  - inode to be freed.
  *
  * RETURN VALUES:
  *  0   - success
  *  -EIO    - i/o error.
  */
 int diFree(struct inode *ip)
 {
     int rc;
     ino_t inum = ip->i_ino;
     struct iag *iagp, *aiagp, *biagp, *ciagp, *diagp;
     struct metapage *mp, *amp, *bmp, *cmp, *dmp;
     int iagno, ino, extno, bitno, sword, agno;
     int back, fwd;
     u32 bitmap, mask;
     struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap;
     struct inomap *imap = JFS_IP(ipimap)->i_imap;
     pxd_t freepxd;
     tid_t tid;
     struct inode *iplist[3];
     struct tlock *tlck;
     struct pxd_lock *pxdlock;
 
     /*
      * This is just to suppress compiler warnings.  The same logic that
      * references these variables is used to initialize them.
      */
     aiagp = biagp = ciagp = diagp = NULL;
 
     /* get the iag number containing the inode.
      */
     iagno = INOTOIAG(inum);
 
     /* make sure that the iag is contained within
      * the map.
      */
     if (iagno >= imap->im_nextiag) {
         print_hex_dump(KERN_ERR, "imap: ", DUMP_PREFIX_ADDRESS, 16, 4,
                    imap, 32, 0);
         jfs_error(ip->i_sb, "inum = %d, iagno = %d, nextiag = %d\n",
               (uint) inum, iagno, imap->im_nextiag);
         return -EIO;
     }
 
     /* get the allocation group for this ino.
      */
     agno = BLKTOAG(JFS_IP(ip)->agstart, JFS_SBI(ip->i_sb));
 
     /* Lock the AG specific inode map information
      */
     AG_LOCK(imap, agno);
 
     /* Obtain read lock in imap inode.  Don't release it until we have
      * read all of the IAG's that we are going to.
      */
     IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
 
     /* read the iag.
      */
     if ((rc = diIAGRead(imap, iagno, &mp))) {
         IREAD_UNLOCK(ipimap);
         AG_UNLOCK(imap, agno);
         return (rc);
     }
     iagp = (struct iag *) mp->data;
 
     /* get the inode number and extent number of the inode within
      * the iag and the inode number within the extent.
      */
     ino = inum & (INOSPERIAG - 1);
     extno = ino >> L2INOSPEREXT;
     bitno = ino & (INOSPEREXT - 1);
     mask = HIGHORDER >> bitno;
 
     if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
         jfs_error(ip->i_sb, "wmap shows inode already free\n");
     }
 
     if (!addressPXD(&iagp->inoext[extno])) {
         release_metapage(mp);
         IREAD_UNLOCK(ipimap);
         AG_UNLOCK(imap, agno);
         jfs_error(ip->i_sb, "invalid inoext\n");
         return -EIO;
     }
 
     /* compute the bitmap for the extent reflecting the freed inode.
      */
     bitmap = le32_to_cpu(iagp->wmap[extno]) & ~mask;
 
     if (imap->im_agctl[agno].numfree > imap->im_agctl[agno].numinos) {
         release_metapage(mp);
         IREAD_UNLOCK(ipimap);
         AG_UNLOCK(imap, agno);
         jfs_error(ip->i_sb, "numfree > numinos\n");
         return -EIO;
     }
     /*
      *  inode extent still has some inodes or below low water mark:
      *  keep the inode extent;
      */
     if (bitmap ||
         imap->im_agctl[agno].numfree < 96 ||
         (imap->im_agctl[agno].numfree < 288 &&
          (((imap->im_agctl[agno].numfree * 100) /
            imap->im_agctl[agno].numinos) <= 25))) {
         /* if the iag currently has no free inodes (i.e.,
          * the inode being freed is the first free inode of iag),
          * insert the iag at head of the inode free list for the ag.
          */
         if (iagp->nfreeinos == 0) {
             /* check if there are any iags on the ag inode
              * free list.  if so, read the first one so that
              * we can link the current iag onto the list at
              * the head.
              */
             if ((fwd = imap->im_agctl[agno].inofree) >= 0) {
                 /* read the iag that currently is the head
                  * of the list.
                  */
                 if ((rc = diIAGRead(imap, fwd, &amp))) {
                     IREAD_UNLOCK(ipimap);
                     AG_UNLOCK(imap, agno);
                     release_metapage(mp);
                     return (rc);
                 }
                 aiagp = (struct iag *) amp->data;
 
                 /* make current head point back to the iag.
                  */
                 aiagp->inofreeback = cpu_to_le32(iagno);
 
                 write_metapage(amp);
             }
 
             /* iag points forward to current head and iag
              * becomes the new head of the list.
              */
             iagp->inofreefwd =
                 cpu_to_le32(imap->im_agctl[agno].inofree);
             iagp->inofreeback = cpu_to_le32(-1);
             imap->im_agctl[agno].inofree = iagno;
         }
         IREAD_UNLOCK(ipimap);
 
         /* update the free inode summary map for the extent if
          * freeing the inode means the extent will now have free
          * inodes (i.e., the inode being freed is the first free
          * inode of extent),
          */
         if (iagp->wmap[extno] == cpu_to_le32(ONES)) {
             sword = extno >> L2EXTSPERSUM;
             bitno = extno & (EXTSPERSUM - 1);
             iagp->inosmap[sword] &=
                 cpu_to_le32(~(HIGHORDER >> bitno));
         }
 
         /* update the bitmap.
          */
         iagp->wmap[extno] = cpu_to_le32(bitmap);
 
         /* update the free inode counts at the iag, ag and
          * map level.
          */
         le32_add_cpu(&iagp->nfreeinos, 1);
         imap->im_agctl[agno].numfree += 1;
         atomic_inc(&imap->im_numfree);
 
         /* release the AG inode map lock
          */
         AG_UNLOCK(imap, agno);
 
         /* write the iag */
         write_metapage(mp);
 
         return (0);
     }
 
 
     /*
      *  inode extent has become free and above low water mark:
      *  free the inode extent;
      */
 
     /*
      *  prepare to update iag list(s) (careful update step 1)
      */
     amp = bmp = cmp = dmp = NULL;
     fwd = back = -1;
 
     /* check if the iag currently has no free extents.  if so,
      * it will be placed on the head of the ag extent free list.
      */
     if (iagp->nfreeexts == 0) {
         /* check if the ag extent free list has any iags.
          * if so, read the iag at the head of the list now.
          * this (head) iag will be updated later to reflect
          * the addition of the current iag at the head of
          * the list.
          */
         if ((fwd = imap->im_agctl[agno].extfree) >= 0) {
             if ((rc = diIAGRead(imap, fwd, &amp)))
                 goto error_out;
             aiagp = (struct iag *) amp->data;
         }
     } else {
         /* iag has free extents. check if the addition of a free
          * extent will cause all extents to be free within this
          * iag.  if so, the iag will be removed from the ag extent
          * free list and placed on the inode map's free iag list.
          */
         if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG - 1)) {
             /* in preparation for removing the iag from the
              * ag extent free list, read the iags preceding
              * and following the iag on the ag extent free
              * list.
              */
             if ((fwd = le32_to_cpu(iagp->extfreefwd)) >= 0) {
                 if ((rc = diIAGRead(imap, fwd, &amp)))
                     goto error_out;
                 aiagp = (struct iag *) amp->data;
             }
 
             if ((back = le32_to_cpu(iagp->extfreeback)) >= 0) {
                 if ((rc = diIAGRead(imap, back, &bmp)))
                     goto error_out;
                 biagp = (struct iag *) bmp->data;
             }
         }
     }
 
     /* remove the iag from the ag inode free list if freeing
      * this extent cause the iag to have no free inodes.
      */
     if (iagp->nfreeinos == cpu_to_le32(INOSPEREXT - 1)) {
         int inofreeback = le32_to_cpu(iagp->inofreeback);
         int inofreefwd = le32_to_cpu(iagp->inofreefwd);
 
         /* in preparation for removing the iag from the
          * ag inode free list, read the iags preceding
          * and following the iag on the ag inode free
          * list.  before reading these iags, we must make
          * sure that we already don't have them in hand
          * from up above, since re-reading an iag (buffer)
          * we are currently holding would cause a deadlock.
          */
         if (inofreefwd >= 0) {
 
             if (inofreefwd == fwd)
                 ciagp = (struct iag *) amp->data;
             else if (inofreefwd == back)
                 ciagp = (struct iag *) bmp->data;
             else {
                 if ((rc =
                      diIAGRead(imap, inofreefwd, &cmp)))
                     goto error_out;
                 ciagp = (struct iag *) cmp->data;
             }
             assert(ciagp != NULL);
         }
 
         if (inofreeback >= 0) {
             if (inofreeback == fwd)
                 diagp = (struct iag *) amp->data;
             else if (inofreeback == back)
                 diagp = (struct iag *) bmp->data;
             else {
                 if ((rc =
                      diIAGRead(imap, inofreeback, &dmp)))
                     goto error_out;
                 diagp = (struct iag *) dmp->data;
             }
             assert(diagp != NULL);
         }
     }
 
     IREAD_UNLOCK(ipimap);
 
     /*
      * invalidate any page of the inode extent freed from buffer cache;
      */
     freepxd = iagp->inoext[extno];
     invalidate_pxd_metapages(ip, freepxd);
 
     /*
      *  update iag list(s) (careful update step 2)
      */
     /* add the iag to the ag extent free list if this is the
      * first free extent for the iag.
      */
     if (iagp->nfreeexts == 0) {
         if (fwd >= 0)
             aiagp->extfreeback = cpu_to_le32(iagno);
 
         iagp->extfreefwd =
             cpu_to_le32(imap->im_agctl[agno].extfree);
         iagp->extfreeback = cpu_to_le32(-1);
         imap->im_agctl[agno].extfree = iagno;
     } else {
         /* remove the iag from the ag extent list if all extents
          * are now free and place it on the inode map iag free list.
          */
         if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG - 1)) {
             if (fwd >= 0)
                 aiagp->extfreeback = iagp->extfreeback;
 
             if (back >= 0)
                 biagp->extfreefwd = iagp->extfreefwd;
             else
                 imap->im_agctl[agno].extfree =
                     le32_to_cpu(iagp->extfreefwd);
 
             iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
 
             IAGFREE_LOCK(imap);
             iagp->iagfree = cpu_to_le32(imap->im_freeiag);
             imap->im_freeiag = iagno;
             IAGFREE_UNLOCK(imap);
         }
     }
 
     /* remove the iag from the ag inode free list if freeing
      * this extent causes the iag to have no free inodes.
      */
     if (iagp->nfreeinos == cpu_to_le32(INOSPEREXT - 1)) {
         if ((int) le32_to_cpu(iagp->inofreefwd) >= 0)
             ciagp->inofreeback = iagp->inofreeback;
 
         if ((int) le32_to_cpu(iagp->inofreeback) >= 0)
             diagp->inofreefwd = iagp->inofreefwd;
         else
             imap->im_agctl[agno].inofree =
                 le32_to_cpu(iagp->inofreefwd);
 
         iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
     }
 
     /* update the inode extent address and working map
      * to reflect the free extent.
      * the permanent map should have been updated already
      * for the inode being freed.
      */
     if (iagp->pmap[extno] != 0) {
         jfs_error(ip->i_sb, "the pmap does not show inode free\n");
     }
     iagp->wmap[extno] = 0;
     PXDlength(&iagp->inoext[extno], 0);
     PXDaddress(&iagp->inoext[extno], 0);
 
     /* update the free extent and free inode summary maps
      * to reflect the freed extent.
      * the inode summary map is marked to indicate no inodes
      * available for the freed extent.
      */
     sword = extno >> L2EXTSPERSUM;
     bitno = extno & (EXTSPERSUM - 1);
     mask = HIGHORDER >> bitno;
     iagp->inosmap[sword] |= cpu_to_le32(mask);
     iagp->extsmap[sword] &= cpu_to_le32(~mask);
 
     /* update the number of free inodes and number of free extents
      * for the iag.
      */
     le32_add_cpu(&iagp->nfreeinos, -(INOSPEREXT - 1));
     le32_add_cpu(&iagp->nfreeexts, 1);
 
     /* update the number of free inodes and backed inodes
      * at the ag and inode map level.
      */
     imap->im_agctl[agno].numfree -= (INOSPEREXT - 1);
     imap->im_agctl[agno].numinos -= INOSPEREXT;
     atomic_sub(INOSPEREXT - 1, &imap->im_numfree);
     atomic_sub(INOSPEREXT, &imap->im_numinos);
 
     if (amp)
         write_metapage(amp);
     if (bmp)
         write_metapage(bmp);
     if (cmp)
         write_metapage(cmp);
     if (dmp)
         write_metapage(dmp);
 
     /*
      * start transaction to update block allocation map
      * for the inode extent freed;
      *
      * N.B. AG_LOCK is released and iag will be released below, and
      * other thread may allocate inode from/reusing the ixad freed
      * BUT with new/different backing inode extent from the extent
      * to be freed by the transaction;
      */
     tid = txBegin(ipimap->i_sb, COMMIT_FORCE);
     mutex_lock(&JFS_IP(ipimap)->commit_mutex);
 
     /* acquire tlock of the iag page of the freed ixad
      * to force the page NOHOMEOK (even though no data is
      * logged from the iag page) until NOREDOPAGE|FREEXTENT log
      * for the free of the extent is committed;
      * write FREEXTENT|NOREDOPAGE log record
      * N.B. linelock is overlaid as freed extent descriptor;
      */
     tlck = txLock(tid, ipimap, mp, tlckINODE | tlckFREE);
     pxdlock = (struct pxd_lock *) & tlck->lock;
     pxdlock->flag = mlckFREEPXD;
     pxdlock->pxd = freepxd;
     pxdlock->index = 1;
 
     write_metapage(mp);
 
     iplist[0] = ipimap;
 
     /*
      * logredo needs the IAG number and IAG extent index in order
      * to ensure that the IMap is consistent.  The least disruptive
      * way to pass these values through  to the transaction manager
      * is in the iplist array.
      *
      * It's not pretty, but it works.
      */
     iplist[1] = (struct inode *) (size_t)iagno;
     iplist[2] = (struct inode *) (size_t)extno;
 
     rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
 
     txEnd(tid);
     mutex_unlock(&JFS_IP(ipimap)->commit_mutex);
 
     /* unlock the AG inode map information */
     AG_UNLOCK(imap, agno);
 
     return (0);
 
       error_out:
     IREAD_UNLOCK(ipimap);
 
     if (amp)
         release_metapage(amp);
     if (bmp)
         release_metapage(bmp);
     if (cmp)
         release_metapage(cmp);
     if (dmp)
         release_metapage(dmp);
 
     AG_UNLOCK(imap, agno);
 
     release_metapage(mp);
 
     return (rc);
 }
 
 /*
  * There are several places in the diAlloc* routines where we initialize
  * the inode.
  */
 static inline void
 diInitInode(struct inode *ip, int iagno, int ino, int extno, struct iag * iagp)
 {
     struct jfs_inode_info *jfs_ip = JFS_IP(ip);
 
     ip->i_ino = (iagno << L2INOSPERIAG) + ino;
     jfs_ip->ixpxd = iagp->inoext[extno];
     jfs_ip->agstart = le64_to_cpu(iagp->agstart);
     jfs_ip->active_ag = -1;
 }
 
 
 /*
  * NAME:    diAlloc(pip,dir,ip)
  *
  * FUNCTION:    allocate a disk inode from the inode working map
  *      for a fileset or aggregate.
  *
  * PARAMETERS:
  *  pip - pointer to incore inode for the parent inode.
  *  dir - 'true' if the new disk inode is for a directory.
  *  ip  - pointer to a new inode
  *
  * RETURN VALUES:
  *  0   - success.
  *  -ENOSPC - insufficient disk resources.
  *  -EIO    - i/o error.
  */
 int diAlloc(struct inode *pip, bool dir, struct inode *ip)
 {
     int rc, ino, iagno, addext, extno, bitno, sword;
     int nwords, rem, i, agno;
     u32 mask, inosmap, extsmap;
     struct inode *ipimap;
     struct metapage *mp;
     ino_t inum;
     struct iag *iagp;
     struct inomap *imap;
 
     /* get the pointers to the inode map inode and the
      * corresponding imap control structure.
      */
     ipimap = JFS_SBI(pip->i_sb)->ipimap;
     imap = JFS_IP(ipimap)->i_imap;
     JFS_IP(ip)->ipimap = ipimap;
     JFS_IP(ip)->fileset = FILESYSTEM_I;
 
     /* for a directory, the allocation policy is to start
      * at the ag level using the preferred ag.
      */
     if (dir) {
         agno = dbNextAG(JFS_SBI(pip->i_sb)->ipbmap);
         AG_LOCK(imap, agno);
         goto tryag;
     }
 
     /* for files, the policy starts off by trying to allocate from
      * the same iag containing the parent disk inode:
      * try to allocate the new disk inode close to the parent disk
      * inode, using parent disk inode number + 1 as the allocation
      * hint.  (we use a left-to-right policy to attempt to avoid
      * moving backward on the disk.)  compute the hint within the
      * file system and the iag.
      */
 
     /* get the ag number of this iag */
     agno = BLKTOAG(JFS_IP(pip)->agstart, JFS_SBI(pip->i_sb));
 
     if (atomic_read(&JFS_SBI(pip->i_sb)->bmap->db_active[agno])) {
         /*
          * There is an open file actively growing.  We want to
          * allocate new inodes from a different ag to avoid
          * fragmentation problems.
          */
         agno = dbNextAG(JFS_SBI(pip->i_sb)->ipbmap);
         AG_LOCK(imap, agno);
         goto tryag;
     }
 
     inum = pip->i_ino + 1;
     ino = inum & (INOSPERIAG - 1);
 
     /* back off the hint if it is outside of the iag */
     if (ino == 0)
         inum = pip->i_ino;
 
     /* lock the AG inode map information */
     AG_LOCK(imap, agno);
 
     /* Get read lock on imap inode */
     IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
 
     /* get the iag number and read the iag */
     iagno = INOTOIAG(inum);
     if ((rc = diIAGRead(imap, iagno, &mp))) {
         IREAD_UNLOCK(ipimap);
         AG_UNLOCK(imap, agno);
         return (rc);
     }
     iagp = (struct iag *) mp->data;
 
     /* determine if new inode extent is allowed to be added to the iag.
      * new inode extent can be added to the iag if the ag
      * has less than 32 free disk inodes and the iag has free extents.
      */
     addext = (imap->im_agctl[agno].numfree < 32 && iagp->nfreeexts);
 
     /*
      *  try to allocate from the IAG
      */
     /* check if the inode may be allocated from the iag
      * (i.e. the inode has free inodes or new extent can be added).
      */
     if (iagp->nfreeinos || addext) {
         /* determine the extent number of the hint.
          */
         extno = ino >> L2INOSPEREXT;
 
         /* check if the extent containing the hint has backed
          * inodes.  if so, try to allocate within this extent.
          */
         if (addressPXD(&iagp->inoext[extno])) {
             bitno = ino & (INOSPEREXT - 1);
             if ((bitno =
                  diFindFree(le32_to_cpu(iagp->wmap[extno]),
                     bitno))
                 < INOSPEREXT) {
                 ino = (extno << L2INOSPEREXT) + bitno;
 
                 /* a free inode (bit) was found within this
                  * extent, so allocate it.
                  */
                 rc = diAllocBit(imap, iagp, ino);
                 IREAD_UNLOCK(ipimap);
                 if (rc) {
                     assert(rc == -EIO);
                 } else {
                     /* set the results of the allocation
                      * and write the iag.
                      */
                     diInitInode(ip, iagno, ino, extno,
                             iagp);
                     mark_metapage_dirty(mp);
                 }
                 release_metapage(mp);
 
                 /* free the AG lock and return.
                  */
                 AG_UNLOCK(imap, agno);
                 return (rc);
             }
 
             if (!addext)
                 extno =
                     (extno ==
                      EXTSPERIAG - 1) ? 0 : extno + 1;
         }
 
         /*
          * no free inodes within the extent containing the hint.
          *
          * try to allocate from the backed extents following
          * hint or, if appropriate (i.e. addext is true), allocate
          * an extent of free inodes at or following the extent
          * containing the hint.
          *
          * the free inode and free extent summary maps are used
          * here, so determine the starting summary map position
          * and the number of words we'll have to examine.  again,
          * the approach is to allocate following the hint, so we
          * might have to initially ignore prior bits of the summary
          * map that represent extents prior to the extent containing
          * the hint and later revisit these bits.
          */
         bitno = extno & (EXTSPERSUM - 1);
         nwords = (bitno == 0) ? SMAPSZ : SMAPSZ + 1;
         sword = extno >> L2EXTSPERSUM;
 
         /* mask any prior bits for the starting words of the
          * summary map.
          */
         mask = (bitno == 0) ? 0 : (ONES << (EXTSPERSUM - bitno));
         inosmap = le32_to_cpu(iagp->inosmap[sword]) | mask;
         extsmap = le32_to_cpu(iagp->extsmap[sword]) | mask;
 
         /* scan the free inode and free extent summary maps for
          * free resources.
          */
         for (i = 0; i < nwords; i++) {
             /* check if this word of the free inode summary
              * map describes an extent with free inodes.
              */
             if (~inosmap) {
                 /* an extent with free inodes has been
                  * found. determine the extent number
                  * and the inode number within the extent.
                  */
                 rem = diFindFree(inosmap, 0);
                 extno = (sword << L2EXTSPERSUM) + rem;
                 rem = diFindFree(le32_to_cpu(iagp->wmap[extno]),
                          0);
                 if (rem >= INOSPEREXT) {
                     IREAD_UNLOCK(ipimap);
                     release_metapage(mp);
                     AG_UNLOCK(imap, agno);
                     jfs_error(ip->i_sb,
                           "can't find free bit in wmap\n");
                     return -EIO;
                 }
 
                 /* determine the inode number within the
                  * iag and allocate the inode from the
                  * map.
                  */
                 ino = (extno << L2INOSPEREXT) + rem;
                 rc = diAllocBit(imap, iagp, ino);
                 IREAD_UNLOCK(ipimap);
                 if (rc)
                     assert(rc == -EIO);
                 else {
                     /* set the results of the allocation
                      * and write the iag.
                      */
                     diInitInode(ip, iagno, ino, extno,
                             iagp);
                     mark_metapage_dirty(mp);
                 }
                 release_metapage(mp);
 
                 /* free the AG lock and return.
                  */
                 AG_UNLOCK(imap, agno);
                 return (rc);
 
             }
 
             /* check if we may allocate an extent of free
              * inodes and whether this word of the free
              * extents summary map describes a free extent.
              */
             if (addext && ~extsmap) {
                 /* a free extent has been found.  determine
                  * the extent number.
                  */
                 rem = diFindFree(extsmap, 0);
                 extno = (sword << L2EXTSPERSUM) + rem;
 
                 /* allocate an extent of free inodes.
                  */
                 if ((rc = diNewExt(imap, iagp, extno))) {
                     /* if there is no disk space for a
                      * new extent, try to allocate the
                      * disk inode from somewhere else.
                      */
                     if (rc == -ENOSPC)
                         break;
 
                     assert(rc == -EIO);
                 } else {
                     /* set the results of the allocation
                      * and write the iag.
                      */
                     diInitInode(ip, iagno,
                             extno << L2INOSPEREXT,
                             extno, iagp);
                     mark_metapage_dirty(mp);
                 }
                 release_metapage(mp);
                 /* free the imap inode & the AG lock & return.
                  */
                 IREAD_UNLOCK(ipimap);
                 AG_UNLOCK(imap, agno);
                 return (rc);
             }
 
             /* move on to the next set of summary map words.
              */
             sword = (sword == SMAPSZ - 1) ? 0 : sword + 1;
             inosmap = le32_to_cpu(iagp->inosmap[sword]);
             extsmap = le32_to_cpu(iagp->extsmap[sword]);
         }
     }
     /* unlock imap inode */
     IREAD_UNLOCK(ipimap);
 
     /* nothing doing in this iag, so release it. */
     release_metapage(mp);
 
       tryag:
     /*
      * try to allocate anywhere within the same AG as the parent inode.
      */
     rc = diAllocAG(imap, agno, dir, ip);
 
     AG_UNLOCK(imap, agno);
 
     if (rc != -ENOSPC)
         return (rc);
 
     /*
      * try to allocate in any AG.
      */
     return (diAllocAny(imap, agno, dir, ip));
 }
 
 
 /*
  * NAME:    diAllocAG(imap,agno,dir,ip)
  *
  * FUNCTION:    allocate a disk inode from the allocation group.
  *
  *      this routine first determines if a new extent of free
  *      inodes should be added for the allocation group, with
  *      the current request satisfied from this extent. if this
  *      is the case, an attempt will be made to do just that.  if
  *      this attempt fails or it has been determined that a new
  *      extent should not be added, an attempt is made to satisfy
  *      the request by allocating an existing (backed) free inode
  *      from the allocation group.
  *
  * PRE CONDITION: Already have the AG lock for this AG.
  *
  * PARAMETERS:
  *  imap    - pointer to inode map control structure.
  *  agno    - allocation group to allocate from.
  *  dir - 'true' if the new disk inode is for a directory.
  *  ip  - pointer to the new inode to be filled in on successful return
  *        with the disk inode number allocated, its extent address
  *        and the start of the ag.
  *
  * RETURN VALUES:
  *  0   - success.
  *  -ENOSPC - insufficient disk resources.
  *  -EIO    - i/o error.
  */
 static int
 diAllocAG(struct inomap * imap, int agno, bool dir, struct inode *ip)
 {
     int rc, addext, numfree, numinos;
 
     /* get the number of free and the number of backed disk
      * inodes currently within the ag.
      */
     numfree = imap->im_agctl[agno].numfree;
     numinos = imap->im_agctl[agno].numinos;
 
     if (numfree > numinos) {
         jfs_error(ip->i_sb, "numfree > numinos\n");
         return -EIO;
     }
 
     /* determine if we should allocate a new extent of free inodes
      * within the ag: for directory inodes, add a new extent
      * if there are a small number of free inodes or number of free
      * inodes is a small percentage of the number of backed inodes.
      */
     if (dir)
         addext = (numfree < 64 ||
               (numfree < 256
                && ((numfree * 100) / numinos) <= 20));
     else
         addext = (numfree == 0);
 
     /*
      * try to allocate a new extent of free inodes.
      */
     if (addext) {
         /* if free space is not available for this new extent, try
          * below to allocate a free and existing (already backed)
          * inode from the ag.
          */
         if ((rc = diAllocExt(imap, agno, ip)) != -ENOSPC)
             return (rc);
     }
 
     /*
      * try to allocate an existing free inode from the ag.
      */
     return (diAllocIno(imap, agno, ip));
 }
 
 
 /*
  * NAME:    diAllocAny(imap,agno,dir,iap)
  *
  * FUNCTION:    allocate a disk inode from any other allocation group.
  *
  *      this routine is called when an allocation attempt within
  *      the primary allocation group has failed. if attempts to
  *      allocate an inode from any allocation group other than the
  *      specified primary group.
  *
  * PARAMETERS:
  *  imap    - pointer to inode map control structure.
  *  agno    - primary allocation group (to avoid).
  *  dir - 'true' if the new disk inode is for a directory.
  *  ip  - pointer to a new inode to be filled in on successful return
  *        with the disk inode number allocated, its extent address
  *        and the start of the ag.
  *
  * RETURN VALUES:
  *  0   - success.
  *  -ENOSPC - insufficient disk resources.
  *  -EIO    - i/o error.
  */
 static int
 diAllocAny(struct inomap * imap, int agno, bool dir, struct inode *ip)
 {
     int ag, rc;
     int maxag = JFS_SBI(imap->im_ipimap->i_sb)->bmap->db_maxag;
 
 
     /* try to allocate from the ags following agno up to
      * the maximum ag number.
      */
     for (ag = agno + 1; ag <= maxag; ag++) {
         AG_LOCK(imap, ag);
 
         rc = diAllocAG(imap, ag, dir, ip);
 
         AG_UNLOCK(imap, ag);
 
         if (rc != -ENOSPC)
             return (rc);
     }
 
     /* try to allocate from the ags in front of agno.
      */
     for (ag = 0; ag < agno; ag++) {
         AG_LOCK(imap, ag);
 
         rc = diAllocAG(imap, ag, dir, ip);
 
         AG_UNLOCK(imap, ag);
 
         if (rc != -ENOSPC)
             return (rc);
     }
 
     /* no free disk inodes.
      */
     return -ENOSPC;
 }
 
 
 /*
  * NAME:    diAllocIno(imap,agno,ip)
  *
  * FUNCTION:    allocate a disk inode from the allocation group's free
  *      inode list, returning an error if this free list is
  *      empty (i.e. no iags on the list).
  *
  *      allocation occurs from the first iag on the list using
  *      the iag's free inode summary map to find the leftmost
  *      free inode in the iag.
  *
  * PRE CONDITION: Already have AG lock for this AG.
  *
  * PARAMETERS:
  *  imap    - pointer to inode map control structure.
  *  agno    - allocation group.
  *  ip  - pointer to new inode to be filled in on successful return
  *        with the disk inode number allocated, its extent address
  *        and the start of the ag.
  *
  * RETURN VALUES:
  *  0   - success.
  *  -ENOSPC - insufficient disk resources.
  *  -EIO    - i/o error.
  */
 static int diAllocIno(struct inomap * imap, int agno, struct inode *ip)
 {
     int iagno, ino, rc, rem, extno, sword;
     struct metapage *mp;
     struct iag *iagp;
 
     /* check if there are iags on the ag's free inode list.
      */
     if ((iagno = imap->im_agctl[agno].inofree) < 0)
         return -ENOSPC;
 
     /* obtain read lock on imap inode */
     IREAD_LOCK(imap->im_ipimap, RDWRLOCK_IMAP);
 
     /* read the iag at the head of the list.
      */
     if ((rc = diIAGRead(imap, iagno, &mp))) {
         IREAD_UNLOCK(imap->im_ipimap);
         return (rc);
     }
     iagp = (struct iag *) mp->data;
 
     /* better be free inodes in this iag if it is on the
      * list.
      */
     if (!iagp->nfreeinos) {
         IREAD_UNLOCK(imap->im_ipimap);
         release_metapage(mp);
         jfs_error(ip->i_sb, "nfreeinos = 0, but iag on freelist\n");
         return -EIO;
     }
 
     /* scan the free inode summary map to find an extent
      * with free inodes.
      */
     for (sword = 0;; sword++) {
         if (sword >= SMAPSZ) {
             IREAD_UNLOCK(imap->im_ipimap);
             release_metapage(mp);
             jfs_error(ip->i_sb,
                   "free inode not found in summary map\n");
             return -EIO;
         }
 
         if (~iagp->inosmap[sword])
             break;
     }
 
     /* found a extent with free inodes. determine
      * the extent number.
      */
     rem = diFindFree(le32_to_cpu(iagp->inosmap[sword]), 0);
     if (rem >= EXTSPERSUM) {
         IREAD_UNLOCK(imap->im_ipimap);
         release_metapage(mp);
         jfs_error(ip->i_sb, "no free extent found\n");
         return -EIO;
     }
     extno = (sword << L2EXTSPERSUM) + rem;
 
     /* find the first free inode in the extent.
      */
     rem = diFindFree(le32_to_cpu(iagp->wmap[extno]), 0);
     if (rem >= INOSPEREXT) {
         IREAD_UNLOCK(imap->im_ipimap);
         release_metapage(mp);
         jfs_error(ip->i_sb, "free inode not found\n");
         return -EIO;
     }
 
     /* compute the inode number within the iag.
      */
     ino = (extno << L2INOSPEREXT) + rem;
 
     /* allocate the inode.
      */
     rc = diAllocBit(imap, iagp, ino);
     IREAD_UNLOCK(imap->im_ipimap);
     if (rc) {
         release_metapage(mp);
         return (rc);
     }
 
     /* set the results of the allocation and write the iag.
      */
     diInitInode(ip, iagno, ino, extno, iagp);
     write_metapage(mp);
 
     return (0);
 }
 
 
 /*
  * NAME:    diAllocExt(imap,agno,ip)
  *
  * FUNCTION:    add a new extent of free inodes to an iag, allocating
  *      an inode from this extent to satisfy the current allocation
  *      request.
  *
  *      this routine first tries to find an existing iag with free
  *      extents through the ag free extent list.  if list is not
  *      empty, the head of the list will be selected as the home
  *      of the new extent of free inodes.  otherwise (the list is
  *      empty), a new iag will be allocated for the ag to contain
  *      the extent.
  *
  *      once an iag has been selected, the free extent summary map
  *      is used to locate a free extent within the iag and diNewExt()
  *      is called to initialize the extent, with initialization
  *      including the allocation of the first inode of the extent
  *      for the purpose of satisfying this request.
  *
  * PARAMETERS:
  *  imap    - pointer to inode map control structure.
  *  agno    - allocation group number.
  *  ip  - pointer to new inode to be filled in on successful return
  *        with the disk inode number allocated, its extent address
  *        and the start of the ag.
  *
  * RETURN VALUES:
  *  0   - success.
  *  -ENOSPC - insufficient disk resources.
  *  -EIO    - i/o error.
  */
 static int diAllocExt(struct inomap * imap, int agno, struct inode *ip)
 {
     int rem, iagno, sword, extno, rc;
     struct metapage *mp;
     struct iag *iagp;
 
     /* check if the ag has any iags with free extents.  if not,
      * allocate a new iag for the ag.
      */
     if ((iagno = imap->im_agctl[agno].extfree) < 0) {
         /* If successful, diNewIAG will obtain the read lock on the
          * imap inode.
          */
         if ((rc = diNewIAG(imap, &iagno, agno, &mp))) {
             return (rc);
         }
         iagp = (struct iag *) mp->data;
 
         /* set the ag number if this a brand new iag
          */
         iagp->agstart =
             cpu_to_le64(AGTOBLK(agno, imap->im_ipimap));
     } else {
         /* read the iag.
          */
         IREAD_LOCK(imap->im_ipimap, RDWRLOCK_IMAP);
         if ((rc = diIAGRead(imap, iagno, &mp))) {
             IREAD_UNLOCK(imap->im_ipimap);
             jfs_error(ip->i_sb, "error reading iag\n");
             return rc;
         }
         iagp = (struct iag *) mp->data;
     }
 
     /* using the free extent summary map, find a free extent.
      */
     for (sword = 0;; sword++) {
         if (sword >= SMAPSZ) {
             release_metapage(mp);
             IREAD_UNLOCK(imap->im_ipimap);
             jfs_error(ip->i_sb, "free ext summary map not found\n");
             return -EIO;
         }
         if (~iagp->extsmap[sword])
             break;
     }
 
     /* determine the extent number of the free extent.
      */
     rem = diFindFree(le32_to_cpu(iagp->extsmap[sword]), 0);
     if (rem >= EXTSPERSUM) {
         release_metapage(mp);
         IREAD_UNLOCK(imap->im_ipimap);
         jfs_error(ip->i_sb, "free extent not found\n");
         return -EIO;
     }
     extno = (sword << L2EXTSPERSUM) + rem;
 
     /* initialize the new extent.
      */
     rc = diNewExt(imap, iagp, extno);
     IREAD_UNLOCK(imap->im_ipimap);
     if (rc) {
         /* something bad happened.  if a new iag was allocated,
          * place it back on the inode map's iag free list, and
          * clear the ag number information.
          */
         if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
             IAGFREE_LOCK(imap);
             iagp->iagfree = cpu_to_le32(imap->im_freeiag);
             imap->im_freeiag = iagno;
             IAGFREE_UNLOCK(imap);
         }
         write_metapage(mp);
         return (rc);
     }
 
     /* set the results of the allocation and write the iag.
      */
     diInitInode(ip, iagno, extno << L2INOSPEREXT, extno, iagp);
 
     write_metapage(mp);
 
     return (0);
 }
 
 
 /*
  * NAME:    diAllocBit(imap,iagp,ino)
  *
  * FUNCTION:    allocate a backed inode from an iag.
  *
  *      this routine performs the mechanics of allocating a
  *      specified inode from a backed extent.
  *
  *      if the inode to be allocated represents the last free
  *      inode within the iag, the iag will be removed from the
  *      ag free inode list.
  *
  *      a careful update approach is used to provide consistency
  *      in the face of updates to multiple buffers.  under this
  *      approach, all required buffers are obtained before making
  *      any updates and are held all are updates are complete.
  *
  * PRE CONDITION: Already have buffer lock on iagp.  Already have AG lock on
  *  this AG.  Must have read lock on imap inode.
  *
  * PARAMETERS:
  *  imap    - pointer to inode map control structure.
  *  iagp    - pointer to iag.
  *  ino - inode number to be allocated within the iag.
  *
  * RETURN VALUES:
  *  0   - success.
  *  -ENOSPC - insufficient disk resources.
  *  -EIO    - i/o error.
  */
 static int diAllocBit(struct inomap * imap, struct iag * iagp, int ino)
 {
     int extno, bitno, agno, sword, rc;
     struct metapage *amp = NULL, *bmp = NULL;
     struct iag *aiagp = NULL, *biagp = NULL;
     u32 mask;
 
     /* check if this is the last free inode within the iag.
      * if so, it will have to be removed from the ag free
      * inode list, so get the iags preceding and following
      * it on the list.
      */
     if (iagp->nfreeinos == cpu_to_le32(1)) {
         if ((int) le32_to_cpu(iagp->inofreefwd) >= 0) {
             if ((rc =
                  diIAGRead(imap, le32_to_cpu(iagp->inofreefwd),
                        &amp)))
                 return (rc);
             aiagp = (struct iag *) amp->data;
         }
 
         if ((int) le32_to_cpu(iagp->inofreeback) >= 0) {
             if ((rc =
                  diIAGRead(imap,
                        le32_to_cpu(iagp->inofreeback),
                        &bmp))) {
                 if (amp)
                     release_metapage(amp);
                 return (rc);
             }
             biagp = (struct iag *) bmp->data;
         }
     }
 
     /* get the ag number, extent number, inode number within
      * the extent.
      */
     agno = BLKTOAG(le64_to_cpu(iagp->agstart), JFS_SBI(imap->im_ipimap->i_sb));
     extno = ino >> L2INOSPEREXT;
     bitno = ino & (INOSPEREXT - 1);
 
     /* compute the mask for setting the map.
      */
     mask = HIGHORDER >> bitno;
 
     /* the inode should be free and backed.
      */
     if (((le32_to_cpu(iagp->pmap[extno]) & mask) != 0) ||
         ((le32_to_cpu(iagp->wmap[extno]) & mask) != 0) ||
         (addressPXD(&iagp->inoext[extno]) == 0)) {
         if (amp)
             release_metapage(amp);
         if (bmp)
             release_metapage(bmp);
 
         jfs_error(imap->im_ipimap->i_sb, "iag inconsistent\n");
         return -EIO;
     }
 
     /* mark the inode as allocated in the working map.
      */
     iagp->wmap[extno] |= cpu_to_le32(mask);
 
     /* check if all inodes within the extent are now
      * allocated.  if so, update the free inode summary
      * map to reflect this.
      */
     if (iagp->wmap[extno] == cpu_to_le32(ONES)) {
         sword = extno >> L2EXTSPERSUM;
         bitno = extno & (EXTSPERSUM - 1);
         iagp->inosmap[sword] |= cpu_to_le32(HIGHORDER >> bitno);
     }
 
     /* if this was the last free inode in the iag, remove the
      * iag from the ag free inode list.
      */
     if (iagp->nfreeinos == cpu_to_le32(1)) {
         if (amp) {
             aiagp->inofreeback = iagp->inofreeback;
             write_metapage(amp);
         }
 
         if (bmp) {
             biagp->inofreefwd = iagp->inofreefwd;
             write_metapage(bmp);
         } else {
             imap->im_agctl[agno].inofree =
                 le32_to_cpu(iagp->inofreefwd);
         }
         iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
     }
 
     /* update the free inode count at the iag, ag, inode
      * map levels.
      */
     le32_add_cpu(&iagp->nfreeinos, -1);
     imap->im_agctl[agno].numfree -= 1;
     atomic_dec(&imap->im_numfree);
 
     return (0);
 }
 
 
 /*
  * NAME:    diNewExt(imap,iagp,extno)
  *
  * FUNCTION:    initialize a new extent of inodes for an iag, allocating
  *      the first inode of the extent for use for the current
  *      allocation request.
  *
  *      disk resources are allocated for the new extent of inodes
  *      and the inodes themselves are initialized to reflect their
  *      existence within the extent (i.e. their inode numbers and
  *      inode extent addresses are set) and their initial state
  *      (mode and link count are set to zero).
  *
  *      if the iag is new, it is not yet on an ag extent free list
  *      but will now be placed on this list.
  *
  *      if the allocation of the new extent causes the iag to
  *      have no free extent, the iag will be removed from the
  *      ag extent free list.
  *
  *      if the iag has no free backed inodes, it will be placed
  *      on the ag free inode list, since the addition of the new
  *      extent will now cause it to have free inodes.
  *
  *      a careful update approach is used to provide consistency
  *      (i.e. list consistency) in the face of updates to multiple
  *      buffers.  under this approach, all required buffers are
  *      obtained before making any updates and are held until all
  *      updates are complete.
  *
  * PRE CONDITION: Already have buffer lock on iagp.  Already have AG lock on
  *  this AG.  Must have read lock on imap inode.
  *
  * PARAMETERS:
  *  imap    - pointer to inode map control structure.
  *  iagp    - pointer to iag.
  *  extno   - extent number.
  *
  * RETURN VALUES:
  *  0   - success.
  *  -ENOSPC - insufficient disk resources.
  *  -EIO    - i/o error.
  */
 static int diNewExt(struct inomap * imap, struct iag * iagp, int extno)
 {
     int agno, iagno, fwd, back, freei = 0, sword, rc;
     struct iag *aiagp = NULL, *biagp = NULL, *ciagp = NULL;
     struct metapage *amp, *bmp, *cmp, *dmp;
     struct inode *ipimap;
     s64 blkno, hint;
     int i, j;
     u32 mask;
     ino_t ino;
     struct dinode *dp;
     struct jfs_sb_info *sbi;
 
     /* better have free extents.
      */
     if (!iagp->nfreeexts) {
         jfs_error(imap->im_ipimap->i_sb, "no free extents\n");
         return -EIO;
     }
 
     /* get the inode map inode.
      */
     ipimap = imap->im_ipimap;
     sbi = JFS_SBI(ipimap->i_sb);
 
     amp = bmp = cmp = NULL;
 
     /* get the ag and iag numbers for this iag.
      */
     agno = BLKTOAG(le64_to_cpu(iagp->agstart), sbi);
     iagno = le32_to_cpu(iagp->iagnum);
 
     /* check if this is the last free extent within the
      * iag.  if so, the iag must be removed from the ag
      * free extent list, so get the iags preceding and
      * following the iag on this list.
      */
     if (iagp->nfreeexts == cpu_to_le32(1)) {
         if ((fwd = le32_to_cpu(iagp->extfreefwd)) >= 0) {
             if ((rc = diIAGRead(imap, fwd, &amp)))
                 return (rc);
             aiagp = (struct iag *) amp->data;
         }
 
         if ((back = le32_to_cpu(iagp->extfreeback)) >= 0) {
             if ((rc = diIAGRead(imap, back, &bmp)))
                 goto error_out;
             biagp = (struct iag *) bmp->data;
         }
     } else {
         /* the iag has free extents.  if all extents are free
          * (as is the case for a newly allocated iag), the iag
          * must be added to the ag free extent list, so get
          * the iag at the head of the list in preparation for
          * adding this iag to this list.
          */
         fwd = back = -1;
         if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
             if ((fwd = imap->im_agctl[agno].extfree) >= 0) {
                 if ((rc = diIAGRead(imap, fwd, &amp)))
                     goto error_out;
                 aiagp = (struct iag *) amp->data;
             }
         }
     }
 
     /* check if the iag has no free inodes.  if so, the iag
      * will have to be added to the ag free inode list, so get
      * the iag at the head of the list in preparation for
      * adding this iag to this list.  in doing this, we must
      * check if we already have the iag at the head of
      * the list in hand.
      */
     if (iagp->nfreeinos == 0) {
         freei = imap->im_agctl[agno].inofree;
 
         if (freei >= 0) {
             if (freei == fwd) {
                 ciagp = aiagp;
             } else if (freei == back) {
                 ciagp = biagp;
             } else {
                 if ((rc = diIAGRead(imap, freei, &cmp)))
                     goto error_out;
                 ciagp = (struct iag *) cmp->data;
             }
             if (ciagp == NULL) {
                 jfs_error(imap->im_ipimap->i_sb,
                       "ciagp == NULL\n");
                 rc = -EIO;
                 goto error_out;
             }
         }
     }
 
     /* allocate disk space for the inode extent.
      */
     if ((extno == 0) || (addressPXD(&iagp->inoext[extno - 1]) == 0))
         hint = ((s64) agno << sbi->bmap->db_agl2size) - 1;
     else
         hint = addressPXD(&iagp->inoext[extno - 1]) +
             lengthPXD(&iagp->inoext[extno - 1]) - 1;
 
     if ((rc = dbAlloc(ipimap, hint, (s64) imap->im_nbperiext, &blkno)))
         goto error_out;
 
     /* compute the inode number of the first inode within the
      * extent.
      */
     ino = (iagno << L2INOSPERIAG) + (extno << L2INOSPEREXT);
 
     /* initialize the inodes within the newly allocated extent a
      * page at a time.
      */
     for (i = 0; i < imap->im_nbperiext; i += sbi->nbperpage) {
         /* get a buffer for this page of disk inodes.
          */
         dmp = get_metapage(ipimap, blkno + i, PSIZE, 1);
         if (dmp == NULL) {
             rc = -EIO;
             goto error_out;
         }
         dp = (struct dinode *) dmp->data;
 
         /* initialize the inode number, mode, link count and
          * inode extent address.
          */
         for (j = 0; j < INOSPERPAGE; j++, dp++, ino++) {
             dp->di_inostamp = cpu_to_le32(sbi->inostamp);
             dp->di_number = cpu_to_le32(ino);
             dp->di_fileset = cpu_to_le32(FILESYSTEM_I);
             dp->di_mode = 0;
             dp->di_nlink = 0;
             PXDaddress(&(dp->di_ixpxd), blkno);
             PXDlength(&(dp->di_ixpxd), imap->im_nbperiext);
         }
         write_metapage(dmp);
     }
 
     /* if this is the last free extent within the iag, remove the
      * iag from the ag free extent list.
      */
     if (iagp->nfreeexts == cpu_to_le32(1)) {
         if (fwd >= 0)
             aiagp->extfreeback = iagp->extfreeback;
 
         if (back >= 0)
             biagp->extfreefwd = iagp->extfreefwd;
         else
             imap->im_agctl[agno].extfree =
                 le32_to_cpu(iagp->extfreefwd);
 
         iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
     } else {
         /* if the iag has all free extents (newly allocated iag),
          * add the iag to the ag free extent list.
          */
         if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
             if (fwd >= 0)
                 aiagp->extfreeback = cpu_to_le32(iagno);
 
             iagp->extfreefwd = cpu_to_le32(fwd);
             iagp->extfreeback = cpu_to_le32(-1);
             imap->im_agctl[agno].extfree = iagno;
         }
     }
 
     /* if the iag has no free inodes, add the iag to the
      * ag free inode list.
      */
     if (iagp->nfreeinos == 0) {
         if (freei >= 0)
             ciagp->inofreeback = cpu_to_le32(iagno);
 
         iagp->inofreefwd =
             cpu_to_le32(imap->im_agctl[agno].inofree);
         iagp->inofreeback = cpu_to_le32(-1);
         imap->im_agctl[agno].inofree = iagno;
     }
 
     /* initialize the extent descriptor of the extent. */
     PXDlength(&iagp->inoext[extno], imap->im_nbperiext);
     PXDaddress(&iagp->inoext[extno], blkno);
 
     /* initialize the working and persistent map of the extent.
      * the working map will be initialized such that
      * it indicates the first inode of the extent is allocated.
      */
     iagp->wmap[extno] = cpu_to_le32(HIGHORDER);
     iagp->pmap[extno] = 0;
 
     /* update the free inode and free extent summary maps
      * for the extent to indicate the extent has free inodes
      * and no longer represents a free extent.
      */
     sword = extno >> L2EXTSPERSUM;
     mask = HIGHORDER >> (extno & (EXTSPERSUM - 1));
     iagp->extsmap[sword] |= cpu_to_le32(mask);
     iagp->inosmap[sword] &= cpu_to_le32(~mask);
 
     /* update the free inode and free extent counts for the
      * iag.
      */
     le32_add_cpu(&iagp->nfreeinos, (INOSPEREXT - 1));
     le32_add_cpu(&iagp->nfreeexts, -1);
 
     /* update the free and backed inode counts for the ag.
      */
     imap->im_agctl[agno].numfree += (INOSPEREXT - 1);
     imap->im_agctl[agno].numinos += INOSPEREXT;
 
     /* update the free and backed inode counts for the inode map.
      */
     atomic_add(INOSPEREXT - 1, &imap->im_numfree);
     atomic_add(INOSPEREXT, &imap->im_numinos);
 
     /* write the iags.
      */
     if (amp)
         write_metapage(amp);
     if (bmp)
         write_metapage(bmp);
     if (cmp)
         write_metapage(cmp);
 
     return (0);
 
       error_out:
 
     /* release the iags.
      */
     if (amp)
         release_metapage(amp);
     if (bmp)
         release_metapage(bmp);
     if (cmp)
         release_metapage(cmp);
 
     return (rc);
 }
 
 
 /*
  * NAME:    diNewIAG(imap,iagnop,agno)
  *
  * FUNCTION:    allocate a new iag for an allocation group.
  *
  *      first tries to allocate the iag from the inode map
  *      iagfree list:
  *      if the list has free iags, the head of the list is removed
  *      and returned to satisfy the request.
  *      if the inode map's iag free list is empty, the inode map
  *      is extended to hold a new iag. this new iag is initialized
  *      and returned to satisfy the request.
  *
  * PARAMETERS:
  *  imap    - pointer to inode map control structure.
  *  iagnop  - pointer to an iag number set with the number of the
  *        newly allocated iag upon successful return.
  *  agno    - allocation group number.
  *  bpp - Buffer pointer to be filled in with new IAG's buffer
  *
  * RETURN VALUES:
  *  0   - success.
  *  -ENOSPC - insufficient disk resources.
  *  -EIO    - i/o error.
  *
  * serialization:
  *  AG lock held on entry/exit;
  *  write lock on the map is held inside;
  *  read lock on the map is held on successful completion;
  *
  * note: new iag transaction:
  * . synchronously write iag;
  * . write log of xtree and inode of imap;
  * . commit;
  * . synchronous write of xtree (right to left, bottom to top);
  * . at start of logredo(): init in-memory imap with one additional iag page;
  * . at end of logredo(): re-read imap inode to determine
  *   new imap size;
  */
 static int
 diNewIAG(struct inomap * imap, int *iagnop, int agno, struct metapage ** mpp)
 {
     int rc;
     int iagno, i, xlen;
     struct inode *ipimap;
     struct super_block *sb;
     struct jfs_sb_info *sbi;
     struct metapage *mp;
     struct iag *iagp;
     s64 xaddr = 0;
     s64 blkno;
     tid_t tid;
     struct inode *iplist[1];
 
     /* pick up pointers to the inode map and mount inodes */
     ipimap = imap->im_ipimap;
     sb = ipimap->i_sb;
     sbi = JFS_SBI(sb);
 
     /* acquire the free iag lock */
     IAGFREE_LOCK(imap);
 
     /* if there are any iags on the inode map free iag list,
      * allocate the iag from the head of the list.
      */
     if (imap->im_freeiag >= 0) {
         /* pick up the iag number at the head of the list */
         iagno = imap->im_freeiag;
 
         /* determine the logical block number of the iag */
         blkno = IAGTOLBLK(iagno, sbi->l2nbperpage);
     } else {
         /* no free iags. the inode map will have to be extented
          * to include a new iag.
          */
 
         /* acquire inode map lock */
         IWRITE_LOCK(ipimap, RDWRLOCK_IMAP);
 
         if (ipimap->i_size >> L2PSIZE != imap->im_nextiag + 1) {
             IWRITE_UNLOCK(ipimap);
             IAGFREE_UNLOCK(imap);
             jfs_error(imap->im_ipimap->i_sb,
                   "ipimap->i_size is wrong\n");
             return -EIO;
         }
 
 
         /* get the next available iag number */
         iagno = imap->im_nextiag;
 
         /* make sure that we have not exceeded the maximum inode
          * number limit.
          */
         if (iagno > (MAXIAGS - 1)) {
             /* release the inode map lock */
             IWRITE_UNLOCK(ipimap);
 
             rc = -ENOSPC;
             goto out;
         }
 
         /*
          * synchronously append new iag page.
          */
         /* determine the logical address of iag page to append */
         blkno = IAGTOLBLK(iagno, sbi->l2nbperpage);
 
         /* Allocate extent for new iag page */
         xlen = sbi->nbperpage;
         if ((rc = dbAlloc(ipimap, 0, (s64) xlen, &xaddr))) {
             /* release the inode map lock */
             IWRITE_UNLOCK(ipimap);
 
             goto out;
         }
 
         /*
          * start transaction of update of the inode map
          * addressing structure pointing to the new iag page;
          */
         tid = txBegin(sb, COMMIT_FORCE);
         mutex_lock(&JFS_IP(ipimap)->commit_mutex);
 
         /* update the inode map addressing structure to point to it */
         if ((rc =
              xtInsert(tid, ipimap, 0, blkno, xlen, &xaddr, 0))) {
             txEnd(tid);
             mutex_unlock(&JFS_IP(ipimap)->commit_mutex);
             /* Free the blocks allocated for the iag since it was
              * not successfully added to the inode map
              */
             dbFree(ipimap, xaddr, (s64) xlen);
 
             /* release the inode map lock */
             IWRITE_UNLOCK(ipimap);
 
             goto out;
         }
 
         /* update the inode map's inode to reflect the extension */
         ipimap->i_size += PSIZE;
         inode_add_bytes(ipimap, PSIZE);
 
         /* assign a buffer for the page */
         mp = get_metapage(ipimap, blkno, PSIZE, 0);
         if (!mp) {
             /*
              * This is very unlikely since we just created the
              * extent, but let's try to handle it correctly
              */
             xtTruncate(tid, ipimap, ipimap->i_size - PSIZE,
                    COMMIT_PWMAP);
 
             txAbort(tid, 0);
             txEnd(tid);
             mutex_unlock(&JFS_IP(ipimap)->commit_mutex);
 
             /* release the inode map lock */
             IWRITE_UNLOCK(ipimap);
 
             rc = -EIO;
             goto out;
         }
         iagp = (struct iag *) mp->data;
 
         /* init the iag */
         memset(iagp, 0, sizeof(struct iag));
         iagp->iagnum = cpu_to_le32(iagno);
         iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
         iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
         iagp->iagfree = cpu_to_le32(-1);
         iagp->nfreeinos = 0;
         iagp->nfreeexts = cpu_to_le32(EXTSPERIAG);
 
         /* initialize the free inode summary map (free extent
          * summary map initialization handled by bzero).
          */
         for (i = 0; i < SMAPSZ; i++)
             iagp->inosmap[i] = cpu_to_le32(ONES);
 
         /*
          * Write and sync the metapage
          */
         flush_metapage(mp);
 
         /*
          * txCommit(COMMIT_FORCE) will synchronously write address
          * index pages and inode after commit in careful update order
          * of address index pages (right to left, bottom up);
          */
         iplist[0] = ipimap;
         rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
 
         txEnd(tid);
         mutex_unlock(&JFS_IP(ipimap)->commit_mutex);
 
         duplicateIXtree(sb, blkno, xlen, &xaddr);
 
         /* update the next available iag number */
         imap->im_nextiag += 1;
 
         /* Add the iag to the iag free list so we don't lose the iag
          * if a failure happens now.
          */
         imap->im_freeiag = iagno;
 
         /* Until we have logredo working, we want the imap inode &
          * control page to be up to date.
          */
         diSync(ipimap);
 
         /* release the inode map lock */
         IWRITE_UNLOCK(ipimap);
     }
 
     /* obtain read lock on map */
     IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
 
     /* read the iag */
     if ((rc = diIAGRead(imap, iagno, &mp))) {
         IREAD_UNLOCK(ipimap);
         rc = -EIO;
         goto out;
     }
     iagp = (struct iag *) mp->data;
 
     /* remove the iag from the iag free list */
     imap->im_freeiag = le32_to_cpu(iagp->iagfree);
     iagp->iagfree = cpu_to_le32(-1);
 
     /* set the return iag number and buffer pointer */
     *iagnop = iagno;
     *mpp = mp;
 
       out:
     /* release the iag free lock */
     IAGFREE_UNLOCK(imap);
 
     return (rc);
 }
 
 /*
  * NAME:    diIAGRead()
  *
  * FUNCTION:    get the buffer for the specified iag within a fileset
  *      or aggregate inode map.
  *
  * PARAMETERS:
  *  imap    - pointer to inode map control structure.
  *  iagno   - iag number.
  *  bpp - point to buffer pointer to be filled in on successful
  *        exit.
  *
  * SERIALIZATION:
  *  must have read lock on imap inode
  *  (When called by diExtendFS, the filesystem is quiesced, therefore
  *   the read lock is unnecessary.)
  *
  * RETURN VALUES:
  *  0   - success.
  *  -EIO    - i/o error.
  */
 static int diIAGRead(struct inomap * imap, int iagno, struct metapage ** mpp)
 {
     struct inode *ipimap = imap->im_ipimap;
     s64 blkno;
 
     /* compute the logical block number of the iag. */
     blkno = IAGTOLBLK(iagno, JFS_SBI(ipimap->i_sb)->l2nbperpage);
 
     /* read the iag. */
     *mpp = read_metapage(ipimap, blkno, PSIZE, 0);
     if (*mpp == NULL) {
         return -EIO;
     }
 
     return (0);
 }
 
 /*
  * NAME:    diFindFree()
  *
  * FUNCTION:    find the first free bit in a word starting at
  *      the specified bit position.
  *
  * PARAMETERS:
  *  word    - word to be examined.
  *  start   - starting bit position.
  *
  * RETURN VALUES:
  *  bit position of first free bit in the word or 32 if
  *  no free bits were found.
  */
 static int diFindFree(u32 word, int start)
 {
     int bitno;
     assert(start < 32);
     /* scan the word for the first free bit. */
     for (word <<= start, bitno = start; bitno < 32;
          bitno++, word <<= 1) {
         if ((word & HIGHORDER) == 0)
             break;
     }
     return (bitno);
 }
 
 /*
  * NAME:    diUpdatePMap()
  *
  * FUNCTION: Update the persistent map in an IAG for the allocation or
  *  freeing of the specified inode.
  *
  * PRE CONDITIONS: Working map has already been updated for allocate.
  *
  * PARAMETERS:
  *  ipimap  - Incore inode map inode
  *  inum    - Number of inode to mark in permanent map
  *  is_free - If 'true' indicates inode should be marked freed, otherwise
  *        indicates inode should be marked allocated.
  *
  * RETURN VALUES:
  *      0 for success
  */
 int
 diUpdatePMap(struct inode *ipimap,
          unsigned long inum, bool is_free, struct tblock * tblk)
 {
     int rc;
     struct iag *iagp;
     struct metapage *mp;
     int iagno, ino, extno, bitno;
     struct inomap *imap;
     u32 mask;
     struct jfs_log *log;
     int lsn, difft, diffp;
     unsigned long flags;
 
     imap = JFS_IP(ipimap)->i_imap;
     /* get the iag number containing the inode */
     iagno = INOTOIAG(inum);
     /* make sure that the iag is contained within the map */
     if (iagno >= imap->im_nextiag) {
         jfs_error(ipimap->i_sb, "the iag is outside the map\n");
         return -EIO;
     }
     /* read the iag */
     IREAD_LOCK(ipimap, RDWRLOCK_IMAP);
     rc = diIAGRead(imap, iagno, &mp);
     IREAD_UNLOCK(ipimap);
     if (rc)
         return (rc);
     metapage_wait_for_io(mp);
     iagp = (struct iag *) mp->data;
     /* get the inode number and extent number of the inode within
      * the iag and the inode number within the extent.
      */
     ino = inum & (INOSPERIAG - 1);
     extno = ino >> L2INOSPEREXT;
     bitno = ino & (INOSPEREXT - 1);
     mask = HIGHORDER >> bitno;
     /*
      * mark the inode free in persistent map:
      */
     if (is_free) {
         /* The inode should have been allocated both in working
          * map and in persistent map;
          * the inode will be freed from working map at the release
          * of last reference release;
          */
         if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
             jfs_error(ipimap->i_sb,
                   "inode %ld not marked as allocated in wmap!\n",
                   inum);
         }
         if (!(le32_to_cpu(iagp->pmap[extno]) & mask)) {
             jfs_error(ipimap->i_sb,
                   "inode %ld not marked as allocated in pmap!\n",
                   inum);
         }
         /* update the bitmap for the extent of the freed inode */
         iagp->pmap[extno] &= cpu_to_le32(~mask);
     }
     /*
      * mark the inode allocated in persistent map:
      */
     else {
         /* The inode should be already allocated in the working map
          * and should be free in persistent map;
          */
         if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
             release_metapage(mp);
             jfs_error(ipimap->i_sb,
                   "the inode is not allocated in the working map\n");
             return -EIO;
         }
         if ((le32_to_cpu(iagp->pmap[extno]) & mask) != 0) {
             release_metapage(mp);
             jfs_error(ipimap->i_sb,
                   "the inode is not free in the persistent map\n");
             return -EIO;
         }
         /* update the bitmap for the extent of the allocated inode */
         iagp->pmap[extno] |= cpu_to_le32(mask);
     }
     /*
      * update iag lsn
      */
     lsn = tblk->lsn;
     log = JFS_SBI(tblk->sb)->log;
     LOGSYNC_LOCK(log, flags);
     if (mp->lsn != 0) {
         /* inherit older/smaller lsn */
         logdiff(difft, lsn, log);
         logdiff(diffp, mp->lsn, log);
         if (difft < diffp) {
             mp->lsn = lsn;
             /* move mp after tblock in logsync list */
             list_move(&mp->synclist, &tblk->synclist);
         }
         /* inherit younger/larger clsn */
         assert(mp->clsn);
         logdiff(difft, tblk->clsn, log);
         logdiff(diffp, mp->clsn, log);
         if (difft > diffp)
             mp->clsn = tblk->clsn;
     } else {
         mp->log = log;
         mp->lsn = lsn;
         /* insert mp after tblock in logsync list */
         log->count++;
         list_add(&mp->synclist, &tblk->synclist);
         mp->clsn = tblk->clsn;
     }
     LOGSYNC_UNLOCK(log, flags);
     write_metapage(mp);
     return (0);
 }
 
 /*
  *  diExtendFS()
  *
  * function: update imap for extendfs();
  *
  * note: AG size has been increased s.t. each k old contiguous AGs are
  * coalesced into a new AG;
  */
 int diExtendFS(struct inode *ipimap, struct inode *ipbmap)
 {
     int rc, rcx = 0;
     struct inomap *imap = JFS_IP(ipimap)->i_imap;
     struct iag *iagp = NULL, *hiagp = NULL;
     struct bmap *mp = JFS_SBI(ipbmap->i_sb)->bmap;
     struct metapage *bp, *hbp;
     int i, n, head;
     int numinos, xnuminos = 0, xnumfree = 0;
     s64 agstart;
 
     jfs_info("diExtendFS: nextiag:%d numinos:%d numfree:%d",
            imap->im_nextiag, atomic_read(&imap->im_numinos),
            atomic_read(&imap->im_numfree));
 
     /*
      *  reconstruct imap
      *
      * coalesce contiguous k (newAGSize/oldAGSize) AGs;
      * i.e., (AGi, ..., AGj) where i = k*n and j = k*(n+1) - 1 to AGn;
      * note: new AG size = old AG size * (2**x).
      */
 
     /* init per AG control information im_agctl[] */
     for (i = 0; i < MAXAG; i++) {
         imap->im_agctl[i].inofree = -1;
         imap->im_agctl[i].extfree = -1;
         imap->im_agctl[i].numinos = 0;  /* number of backed inodes */
         imap->im_agctl[i].numfree = 0;  /* number of free backed inodes */
     }
 
     /*
      *  process each iag page of the map.
      *
      * rebuild AG Free Inode List, AG Free Inode Extent List;
      */
     for (i = 0; i < imap->im_nextiag; i++) {
         if ((rc = diIAGRead(imap, i, &bp))) {
             rcx = rc;
             continue;
         }
         iagp = (struct iag *) bp->data;
         if (le32_to_cpu(iagp->iagnum) != i) {
             release_metapage(bp);
             jfs_error(ipimap->i_sb, "unexpected value of iagnum\n");
             return -EIO;
         }
 
         /* leave free iag in the free iag list */
         if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
             release_metapage(bp);
             continue;
         }
 
         agstart = le64_to_cpu(iagp->agstart);
         n = agstart >> mp->db_agl2size;
         iagp->agstart = cpu_to_le64((s64)n << mp->db_agl2size);
 
         /* compute backed inodes */
         numinos = (EXTSPERIAG - le32_to_cpu(iagp->nfreeexts))
             << L2INOSPEREXT;
         if (numinos > 0) {
             /* merge AG backed inodes */
             imap->im_agctl[n].numinos += numinos;
             xnuminos += numinos;
         }
 
         /* if any backed free inodes, insert at AG free inode list */
         if ((int) le32_to_cpu(iagp->nfreeinos) > 0) {
             if ((head = imap->im_agctl[n].inofree) == -1) {
                 iagp->inofreefwd = cpu_to_le32(-1);
                 iagp->inofreeback = cpu_to_le32(-1);
             } else {
                 if ((rc = diIAGRead(imap, head, &hbp))) {
                     rcx = rc;
                     goto nextiag;
                 }
                 hiagp = (struct iag *) hbp->data;
                 hiagp->inofreeback = iagp->iagnum;
                 iagp->inofreefwd = cpu_to_le32(head);
                 iagp->inofreeback = cpu_to_le32(-1);
                 write_metapage(hbp);
             }
 
             imap->im_agctl[n].inofree =
                 le32_to_cpu(iagp->iagnum);
 
             /* merge AG backed free inodes */
             imap->im_agctl[n].numfree +=
                 le32_to_cpu(iagp->nfreeinos);
             xnumfree += le32_to_cpu(iagp->nfreeinos);
         }
 
         /* if any free extents, insert at AG free extent list */
         if (le32_to_cpu(iagp->nfreeexts) > 0) {
             if ((head = imap->im_agctl[n].extfree) == -1) {
                 iagp->extfreefwd = cpu_to_le32(-1);
                 iagp->extfreeback = cpu_to_le32(-1);
             } else {
                 if ((rc = diIAGRead(imap, head, &hbp))) {
                     rcx = rc;
                     goto nextiag;
                 }
                 hiagp = (struct iag *) hbp->data;
                 hiagp->extfreeback = iagp->iagnum;
                 iagp->extfreefwd = cpu_to_le32(head);
                 iagp->extfreeback = cpu_to_le32(-1);
                 write_metapage(hbp);
             }
 
             imap->im_agctl[n].extfree =
                 le32_to_cpu(iagp->iagnum);
         }
 
           nextiag:
         write_metapage(bp);
     }
 
     if (xnuminos != atomic_read(&imap->im_numinos) ||
         xnumfree != atomic_read(&imap->im_numfree)) {
         jfs_error(ipimap->i_sb, "numinos or numfree incorrect\n");
         return -EIO;
     }
 
     return rcx;
 }
 
 
 /*
  *  duplicateIXtree()
  *
  * serialization: IWRITE_LOCK held on entry/exit
  *
  * note: shadow page with regular inode (rel.2);
  */
 static void duplicateIXtree(struct super_block *sb, s64 blkno,
                 int xlen, s64 *xaddr)
 {
     struct jfs_superblock *j_sb;
     struct buffer_head *bh;
     struct inode *ip;
     tid_t tid;
 
     /* if AIT2 ipmap2 is bad, do not try to update it */
     if (JFS_SBI(sb)->mntflag & JFS_BAD_SAIT)    /* s_flag */
         return;
     ip = diReadSpecial(sb, FILESYSTEM_I, 1);
     if (ip == NULL) {
         JFS_SBI(sb)->mntflag |= JFS_BAD_SAIT;
         if (readSuper(sb, &bh))
             return;
         j_sb = (struct jfs_superblock *)bh->b_data;
         j_sb->s_flag |= cpu_to_le32(JFS_BAD_SAIT);
 
         mark_buffer_dirty(bh);
         sync_dirty_buffer(bh);
         brelse(bh);
         return;
     }
 
     /* start transaction */
     tid = txBegin(sb, COMMIT_FORCE);
     /* update the inode map addressing structure to point to it */
     if (xtInsert(tid, ip, 0, blkno, xlen, xaddr, 0)) {
         JFS_SBI(sb)->mntflag |= JFS_BAD_SAIT;
         txAbort(tid, 1);
         goto cleanup;
 
     }
     /* update the inode map's inode to reflect the extension */
     ip->i_size += PSIZE;
     inode_add_bytes(ip, PSIZE);
     txCommit(tid, 1, &ip, COMMIT_FORCE);
       cleanup:
     txEnd(tid);
     diFreeSpecial(ip);
 }
 
 /*
  * NAME:    copy_from_dinode()
  *
  * FUNCTION:    Copies inode info from disk inode to in-memory inode
  *
  * RETURN VALUES:
  *  0   - success
  *  -ENOMEM - insufficient memory
  */
 static int copy_from_dinode(struct dinode * dip, struct inode *ip)
 {
     struct jfs_inode_info *jfs_ip = JFS_IP(ip);
     struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
 
     jfs_ip->fileset = le32_to_cpu(dip->di_fileset);
     jfs_ip->mode2 = le32_to_cpu(dip->di_mode);
     jfs_set_inode_flags(ip);
 
     ip->i_mode = le32_to_cpu(dip->di_mode) & 0xffff;
     if (sbi->umask != -1) {
         ip->i_mode = (ip->i_mode & ~0777) | (0777 & ~sbi->umask);
         /* For directories, add x permission if r is allowed by umask */
         if (S_ISDIR(ip->i_mode)) {
             if (ip->i_mode & 0400)
                 ip->i_mode |= 0100;
             if (ip->i_mode & 0040)
                 ip->i_mode |= 0010;
             if (ip->i_mode & 0004)
                 ip->i_mode |= 0001;
         }
     }
     set_nlink(ip, le32_to_cpu(dip->di_nlink));
 
     jfs_ip->saved_uid = make_kuid(&init_user_ns, le32_to_cpu(dip->di_uid));
     if (!uid_valid(sbi->uid))
         ip->i_uid = jfs_ip->saved_uid;
     else {
         ip->i_uid = sbi->uid;
     }
 
     jfs_ip->saved_gid = make_kgid(&init_user_ns, le32_to_cpu(dip->di_gid));
     if (!gid_valid(sbi->gid))
         ip->i_gid = jfs_ip->saved_gid;
     else {
         ip->i_gid = sbi->gid;
     }
 
     ip->i_size = le64_to_cpu(dip->di_size);
     ip->i_atime.tv_sec = le32_to_cpu(dip->di_atime.tv_sec);
     ip->i_atime.tv_nsec = le32_to_cpu(dip->di_atime.tv_nsec);
     ip->i_mtime.tv_sec = le32_to_cpu(dip->di_mtime.tv_sec);
     ip->i_mtime.tv_nsec = le32_to_cpu(dip->di_mtime.tv_nsec);
     ip->i_ctime.tv_sec = le32_to_cpu(dip->di_ctime.tv_sec);
     ip->i_ctime.tv_nsec = le32_to_cpu(dip->di_ctime.tv_nsec);
     ip->i_blocks = LBLK2PBLK(ip->i_sb, le64_to_cpu(dip->di_nblocks));
     ip->i_generation = le32_to_cpu(dip->di_gen);
 
     jfs_ip->ixpxd = dip->di_ixpxd;  /* in-memory pxd's are little-endian */
     jfs_ip->acl = dip->di_acl;  /* as are dxd's */
     jfs_ip->ea = dip->di_ea;
     jfs_ip->next_index = le32_to_cpu(dip->di_next_index);
     jfs_ip->otime = le32_to_cpu(dip->di_otime.tv_sec);
     jfs_ip->acltype = le32_to_cpu(dip->di_acltype);
 
     if (S_ISCHR(ip->i_mode) || S_ISBLK(ip->i_mode)) {
         jfs_ip->dev = le32_to_cpu(dip->di_rdev);
         ip->i_rdev = new_decode_dev(jfs_ip->dev);
     }
 
     if (S_ISDIR(ip->i_mode)) {
         memcpy(&jfs_ip->u.dir, &dip->u._dir, 384);
     } else if (S_ISREG(ip->i_mode) || S_ISLNK(ip->i_mode)) {
         memcpy(&jfs_ip->i_xtroot, &dip->di_xtroot, 288);
     } else
         memcpy(&jfs_ip->i_inline_ea, &dip->di_inlineea, 128);
 
     /* Zero the in-memory-only stuff */
     jfs_ip->cflag = 0;
     jfs_ip->btindex = 0;
     jfs_ip->btorder = 0;
     jfs_ip->bxflag = 0;
     jfs_ip->blid = 0;
     jfs_ip->atlhead = 0;
     jfs_ip->atltail = 0;
     jfs_ip->xtlid = 0;
     return (0);
 }
 
 /*
  * NAME:    copy_to_dinode()
  *
  * FUNCTION:    Copies inode info from in-memory inode to disk inode
  */
 static void copy_to_dinode(struct dinode * dip, struct inode *ip)
 {
     struct jfs_inode_info *jfs_ip = JFS_IP(ip);
     struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
 
     dip->di_fileset = cpu_to_le32(jfs_ip->fileset);
     dip->di_inostamp = cpu_to_le32(sbi->inostamp);
     dip->di_number = cpu_to_le32(ip->i_ino);
     dip->di_gen = cpu_to_le32(ip->i_generation);
     dip->di_size = cpu_to_le64(ip->i_size);
     dip->di_nblocks = cpu_to_le64(PBLK2LBLK(ip->i_sb, ip->i_blocks));
     dip->di_nlink = cpu_to_le32(ip->i_nlink);
     if (!uid_valid(sbi->uid))
         dip->di_uid = cpu_to_le32(i_uid_read(ip));
     else
         dip->di_uid =cpu_to_le32(from_kuid(&init_user_ns,
                            jfs_ip->saved_uid));
     if (!gid_valid(sbi->gid))
         dip->di_gid = cpu_to_le32(i_gid_read(ip));
     else
         dip->di_gid = cpu_to_le32(from_kgid(&init_user_ns,
                             jfs_ip->saved_gid));
     /*
      * mode2 is only needed for storing the higher order bits.
      * Trust i_mode for the lower order ones
      */
     if (sbi->umask == -1)
         dip->di_mode = cpu_to_le32((jfs_ip->mode2 & 0xffff0000) |
                        ip->i_mode);
     else /* Leave the original permissions alone */
         dip->di_mode = cpu_to_le32(jfs_ip->mode2);
 
     dip->di_atime.tv_sec = cpu_to_le32(ip->i_atime.tv_sec);
     dip->di_atime.tv_nsec = cpu_to_le32(ip->i_atime.tv_nsec);
     dip->di_ctime.tv_sec = cpu_to_le32(ip->i_ctime.tv_sec);
     dip->di_ctime.tv_nsec = cpu_to_le32(ip->i_ctime.tv_nsec);
     dip->di_mtime.tv_sec = cpu_to_le32(ip->i_mtime.tv_sec);
     dip->di_mtime.tv_nsec = cpu_to_le32(ip->i_mtime.tv_nsec);
     dip->di_ixpxd = jfs_ip->ixpxd;  /* in-memory pxd's are little-endian */
     dip->di_acl = jfs_ip->acl;  /* as are dxd's */
     dip->di_ea = jfs_ip->ea;
     dip->di_next_index = cpu_to_le32(jfs_ip->next_index);
     dip->di_otime.tv_sec = cpu_to_le32(jfs_ip->otime);
     dip->di_otime.tv_nsec = 0;
     dip->di_acltype = cpu_to_le32(jfs_ip->acltype);
     if (S_ISCHR(ip->i_mode) || S_ISBLK(ip->i_mode))
         dip->di_rdev = cpu_to_le32(jfs_ip->dev);
 }