/*      $OpenBSD: ffs_balloc.c,v 1.47 2024/04/13 23:44:11 jsg Exp $     */
/*      $NetBSD: ffs_balloc.c,v 1.3 1996/02/09 22:22:21 christos Exp $  */

/*
 * Copyright (c) 2002 Networks Associates Technology, Inc.
 * All rights reserved.
 *
 * This software was developed for the FreeBSD Project by Marshall
 * Kirk McKusick and Network Associates Laboratories, the Security
 * Research Division of Network Associates, Inc. under DARPA/SPAWAR
 * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
 * research program.
 *
 * Copyright (c) 1982, 1986, 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)ffs_balloc.c        8.4 (Berkeley) 9/23/93
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vnode.h>

#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/ufs_extern.h>

#include <ufs/ffs/fs.h>
#include <ufs/ffs/ffs_extern.h>

int ffs1_balloc(struct inode *, off_t, int, struct ucred *, int, struct buf **);
#ifdef FFS2
int ffs2_balloc(struct inode *, off_t, int, struct ucred *, int, struct buf **);
#endif

/*
 * Balloc defines the structure of file system storage
 * by allocating the physical blocks on a device given
 * the inode and the logical block number in a file.
 */
int
ffs1_balloc(struct inode *ip, off_t startoffset, int size, struct ucred *cred,
    int flags, struct buf **bpp)
{
        daddr_t lbn, nb, newb, pref;
        struct fs *fs;
        struct buf *bp, *nbp;
        struct vnode *vp;
        struct proc *p;
        struct indir indirs[NIADDR + 2];
        int32_t *bap;
        int deallocated, osize, nsize, num, i, error;
        int32_t *allocib, *blkp, *allocblk, allociblk[NIADDR+1];
        int unwindidx = -1;

        vp = ITOV(ip);
        fs = ip->i_fs;
        p = curproc;
        lbn = lblkno(fs, startoffset);
        size = blkoff(fs, startoffset) + size;
        if (size > fs->fs_bsize)
                panic("ffs1_balloc: blk too big");
        if (bpp != NULL)
                *bpp = NULL;
        if (lbn < 0)
                return (EFBIG);

        /*
         * If the next write will extend the file into a new block,
         * and the file is currently composed of a fragment
         * this fragment has to be extended to be a full block.
         */
        nb = lblkno(fs, ip->i_ffs1_size);
        if (nb < NDADDR && nb < lbn) {
                osize = blksize(fs, ip, nb);
                if (osize < fs->fs_bsize && osize > 0) {
                        error = ffs_realloccg(ip, nb,
                            ffs1_blkpref(ip, nb, (int)nb, &ip->i_ffs1_db[0]),
                            osize, (int)fs->fs_bsize, cred, bpp, &newb);
                        if (error)
                                return (error);

                        ip->i_ffs1_size = lblktosize(fs, nb + 1);
                        uvm_vnp_setsize(vp, ip->i_ffs1_size);
                        ip->i_ffs1_db[nb] = newb;
                        ip->i_flag |= IN_CHANGE | IN_UPDATE;
                        if (bpp != NULL) {
                                if (flags & B_SYNC)
                                        bwrite(*bpp);
                                else
                                        bawrite(*bpp);
                        }
                }
        }
        /*
         * The first NDADDR blocks are direct blocks
         */
        if (lbn < NDADDR) {
                nb = ip->i_ffs1_db[lbn];
                if (nb != 0 && ip->i_ffs1_size >= lblktosize(fs, lbn + 1)) {
                        /*
                         * The block is an already-allocated direct block
                         * and the file already extends past this block,
                         * thus this must be a whole block.
                         * Just read the block (if requested).
                         */

                        if (bpp != NULL) {
                                error = bread(vp, lbn, fs->fs_bsize, bpp);
                                if (error) {
                                        brelse(*bpp);
                                        return (error);
                                }
                        }
                        return (0);
                }
                if (nb != 0) {
                        /*
                         * Consider need to reallocate a fragment.
                         */
                        osize = fragroundup(fs, blkoff(fs, ip->i_ffs1_size));
                        nsize = fragroundup(fs, size);
                        if (nsize <= osize) {
                                /*
                                 * The existing block is already
                                 * at least as big as we want.
                                 * Just read the block (if requested).
                                 */
                                if (bpp != NULL) {
                                        error = bread(vp, lbn, fs->fs_bsize,
                                            bpp);
                                        if (error) {
                                                brelse(*bpp);
                                                return (error);
                                        }
                                        buf_adjcnt((*bpp), osize);
                                }
                                return (0);
                        } else {
                                /*
                                 * The existing block is smaller than we
                                 * want, grow it.
                                 */
                                error = ffs_realloccg(ip, lbn,
                                    ffs1_blkpref(ip, lbn, (int)lbn,
                                        &ip->i_ffs1_db[0]),
                                    osize, nsize, cred, bpp, &newb);
                                if (error)
                                        return (error);
                        }
                } else {
                        /*
                         * The block was not previously allocated,
                         * allocate a new block or fragment.
                         */

                        if (ip->i_ffs1_size < lblktosize(fs, lbn + 1))
                                nsize = fragroundup(fs, size);
                        else
                                nsize = fs->fs_bsize;
                        error = ffs_alloc(ip, lbn,
                            ffs1_blkpref(ip, lbn, (int)lbn, &ip->i_ffs1_db[0]),
                            nsize, cred, &newb);
                        if (error)
                                return (error);
                        if (bpp != NULL) {
                                *bpp = getblk(vp, lbn, fs->fs_bsize, 0, INFSLP);
                                if (nsize < fs->fs_bsize)
                                        (*bpp)->b_bcount = nsize;
                                (*bpp)->b_blkno = fsbtodb(fs, newb);
                                if (flags & B_CLRBUF)
                                        clrbuf(*bpp);
                        }
                }
                ip->i_ffs1_db[lbn] = newb;
                ip->i_flag |= IN_CHANGE | IN_UPDATE;
                return (0);
        }

        /*
         * Determine the number of levels of indirection.
         */
        pref = 0;
        if ((error = ufs_getlbns(vp, lbn, indirs, &num)) != 0)
                return(error);
#ifdef DIAGNOSTIC
        if (num < 1)
                panic ("ffs1_balloc: ufs_bmaparray returned indirect block");
#endif
        /*
         * Fetch the first indirect block allocating if necessary.
         */
        --num;
        nb = ip->i_ffs1_ib[indirs[0].in_off];

        allocib = NULL;
        allocblk = allociblk;
        if (nb == 0) {
                pref = ffs1_blkpref(ip, lbn, -indirs[0].in_off - 1, NULL);
                error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize,
                                  cred, &newb);
                if (error)
                        goto fail;
                nb = newb;

                *allocblk++ = nb;
                bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, INFSLP);
                bp->b_blkno = fsbtodb(fs, nb);
                clrbuf(bp);

                /*
                 * Write synchronously so that indirect blocks
                 * never point at garbage.
                 */
                if ((error = bwrite(bp)) != 0)
                        goto fail;
                allocib = &ip->i_ffs1_ib[indirs[0].in_off];
                *allocib = nb;
                ip->i_flag |= IN_CHANGE | IN_UPDATE;
        }

        /*
         * Fetch through the indirect blocks, allocating as necessary.
         */
        for (i = 1;;) {
                error = bread(vp, indirs[i].in_lbn, (int)fs->fs_bsize, &bp);
                if (error) {
                        brelse(bp);
                        goto fail;
                }
                bap = (int32_t *)bp->b_data;
                nb = bap[indirs[i].in_off];
                if (i == num)
                        break;
                i++;
                if (nb != 0) {
                        brelse(bp);
                        continue;
                }
                if (pref == 0)
                        pref = ffs1_blkpref(ip, lbn, i - num - 1, NULL);
                error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred,
                                  &newb);
                if (error) {
                        brelse(bp);
                        goto fail;
                }
                nb = newb;
                *allocblk++ = nb;
                nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, INFSLP);
                nbp->b_blkno = fsbtodb(fs, nb);
                clrbuf(nbp);

                /*
                 * Write synchronously so that indirect blocks
                 * never point at garbage.
                 */
                if ((error = bwrite(nbp)) != 0) {
                        brelse(bp);
                        goto fail;
                }
                bap[indirs[i - 1].in_off] = nb;
                if (allocib == NULL && unwindidx < 0)
                        unwindidx = i - 1;
                /*
                 * If required, write synchronously, otherwise use
                 * delayed write.
                 */
                if (flags & B_SYNC) {
                        bwrite(bp);
                } else {
                        bdwrite(bp);
                }
        }
        /*
         * Get the data block, allocating if necessary.
         */
        if (nb == 0) {
                pref = ffs1_blkpref(ip, lbn, indirs[i].in_off, &bap[0]);
                error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred,
                                  &newb);
                if (error) {
                        brelse(bp);
                        goto fail;
                }
                nb = newb;
                *allocblk++ = nb;
                if (bpp != NULL) {
                        nbp = getblk(vp, lbn, fs->fs_bsize, 0, INFSLP);
                        nbp->b_blkno = fsbtodb(fs, nb);
                        if (flags & B_CLRBUF)
                                clrbuf(nbp);
                        *bpp = nbp;
                }
                bap[indirs[i].in_off] = nb;
                /*
                 * If required, write synchronously, otherwise use
                 * delayed write.
                 */
                if (flags & B_SYNC) {
                        bwrite(bp);
                } else {
                        bdwrite(bp);
                }
                return (0);
        }
        brelse(bp);
        if (bpp != NULL) {
                if (flags & B_CLRBUF) {
                        error = bread(vp, lbn, (int)fs->fs_bsize, &nbp);
                        if (error) {
                                brelse(nbp);
                                goto fail;
                        }
                } else {
                        nbp = getblk(vp, lbn, fs->fs_bsize, 0, INFSLP);
                        nbp->b_blkno = fsbtodb(fs, nb);
                }
                *bpp = nbp;
        }
        return (0);

fail:
        /*
         * If we have failed to allocate any blocks, simply return the error.
         * This is the usual case and avoids the need to fsync the file.
         */
        if (allocblk == allociblk && allocib == NULL && unwindidx == -1)
                return (error);
        /*
         * If we have failed part way through block allocation, we have to
         * deallocate any indirect blocks that we have allocated. We have to
         * fsync the file before we start to get rid of all of its
         * dependencies so that we do not leave them dangling. We have to sync
         * it at the end so that the softdep code does not find any untracked
         * changes. Although this is really slow, running out of disk space is
         * not expected to be a common occurrence. The error return from fsync
         * is ignored as we already have an error to return to the user.
         */
        VOP_FSYNC(vp, p->p_ucred, MNT_WAIT, p);
        for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) {
                ffs_blkfree(ip, *blkp, fs->fs_bsize);
                deallocated += fs->fs_bsize;
        }
        if (allocib != NULL) {
                *allocib = 0;
        } else if (unwindidx >= 0) {
                int r;

                r = bread(vp, indirs[unwindidx].in_lbn, (int)fs->fs_bsize, &bp);
                if (r)
                        panic("Could not unwind indirect block, error %d", r);
                bap = (int32_t *)bp->b_data;
                bap[indirs[unwindidx].in_off] = 0;
                if (flags & B_SYNC) {
                        bwrite(bp);
                } else {
                        bdwrite(bp);
                }
        }
        if (deallocated) {
                /*
                 * Restore user's disk quota because allocation failed.
                 */
                (void)ufs_quota_free_blocks(ip, btodb(deallocated), cred);

                ip->i_ffs1_blocks -= btodb(deallocated);
                ip->i_flag |= IN_CHANGE | IN_UPDATE;
        }
        VOP_FSYNC(vp, p->p_ucred, MNT_WAIT, p);
        return (error);
}

#ifdef FFS2
int
ffs2_balloc(struct inode *ip, off_t off, int size, struct ucred *cred,
    int flags, struct buf **bpp)
{
        daddr_t lbn, lastlbn, nb, newb, *blkp;
        daddr_t pref, *allocblk, allociblk[NIADDR + 1];
        daddr_t *bap, *allocib;
        int deallocated, osize, nsize, num, i, error, unwindidx, r;
        struct buf *bp, *nbp;
        struct indir indirs[NIADDR + 2];
        struct fs *fs;
        struct vnode *vp;
        struct proc *p;
        
        vp = ITOV(ip);
        fs = ip->i_fs;
        p = curproc;
        unwindidx = -1;

        lbn = lblkno(fs, off);
        size = blkoff(fs, off) + size;

        if (size > fs->fs_bsize)
                panic("ffs2_balloc: block too big");

        if (bpp != NULL)
                *bpp = NULL;

        if (lbn < 0)
                return (EFBIG);

        /*
         * If the next write will extend the file into a new block, and the
         * file is currently composed of a fragment, this fragment has to be
         * extended to be a full block.
         */
        lastlbn = lblkno(fs, ip->i_ffs2_size);
        if (lastlbn < NDADDR && lastlbn < lbn) {
                nb = lastlbn;
                osize = blksize(fs, ip, nb);
                if (osize < fs->fs_bsize && osize > 0) {
                        error = ffs_realloccg(ip, nb, ffs2_blkpref(ip,
                            lastlbn, nb, &ip->i_ffs2_db[0]), osize,
                            (int) fs->fs_bsize, cred, bpp, &newb);
                        if (error)
                                return (error);

                        ip->i_ffs2_size = lblktosize(fs, nb + 1);
                        uvm_vnp_setsize(vp, ip->i_ffs2_size);
                        ip->i_ffs2_db[nb] = newb;
                        ip->i_flag |= IN_CHANGE | IN_UPDATE;

                        if (bpp) {
                                if (flags & B_SYNC)
                                        bwrite(*bpp);
                                else
                                        bawrite(*bpp);
                        }
                }
        }

        /*
         * The first NDADDR blocks are direct.
         */
        if (lbn < NDADDR) {

                nb = ip->i_ffs2_db[lbn];

                if (nb != 0 && ip->i_ffs2_size >= lblktosize(fs, lbn + 1)) {
                        /*
                         * The direct block is already allocated and the file
                         * extends past this block, thus this must be a whole
                         * block. Just read it, if requested.
                         */
                        if (bpp != NULL) {
                                error = bread(vp, lbn, fs->fs_bsize, bpp);
                                if (error) {
                                        brelse(*bpp);
                                        return (error);
                                }
                        }

                        return (0);
                }

                if (nb != 0) {
                        /*
                         * Consider the need to allocate a fragment.
                         */
                        osize = fragroundup(fs, blkoff(fs, ip->i_ffs2_size));
                        nsize = fragroundup(fs, size);

                        if (nsize <= osize) {
                                /*
                                 * The existing block is already at least as
                                 * big as we want. Just read it, if requested.
                                 */
                                if (bpp != NULL) {
                                        error = bread(vp, lbn, fs->fs_bsize,
                                            bpp);
                                        if (error) {
                                                brelse(*bpp);
                                                return (error);
                                        }
                                        buf_adjcnt((*bpp), osize);
                                }

                                return (0);
                        } else {
                                /*
                                 * The existing block is smaller than we want,
                                 * grow it.
                                 */
                                error = ffs_realloccg(ip, lbn,
                                    ffs2_blkpref(ip, lbn, (int) lbn,
                                    &ip->i_ffs2_db[0]), osize, nsize, cred,
                                    bpp, &newb);
                                if (error)
                                        return (error);
                        }
                } else {
                        /*
                         * The block was not previously allocated, allocate a
                         * new block or fragment.
                         */
                        if (ip->i_ffs2_size < lblktosize(fs, lbn + 1))
                                nsize = fragroundup(fs, size);
                        else
                                nsize = fs->fs_bsize;

                        error = ffs_alloc(ip, lbn, ffs2_blkpref(ip, lbn,
                            (int) lbn, &ip->i_ffs2_db[0]), nsize, cred, &newb);
                        if (error)
                                return (error);

                        if (bpp != NULL) {
                                bp = getblk(vp, lbn, fs->fs_bsize, 0, INFSLP);
                                if (nsize < fs->fs_bsize)
                                        bp->b_bcount = nsize;
                                bp->b_blkno = fsbtodb(fs, newb);
                                if (flags & B_CLRBUF)
                                        clrbuf(bp);
                                *bpp = bp;
                        }
                }

                ip->i_ffs2_db[lbn] = newb;
                ip->i_flag |= IN_CHANGE | IN_UPDATE;

                return (0);
        }

        /*
         * Determine the number of levels of indirection.
         */
        pref = 0;
        error = ufs_getlbns(vp, lbn, indirs, &num);
        if (error)
                return (error);

#ifdef DIAGNOSTIC
        if (num < 1)
                panic("ffs2_balloc: ufs_bmaparray returned indirect block");
#endif

        /*
         * Fetch the first indirect block allocating it necessary.
         */
        --num;
        nb = ip->i_ffs2_ib[indirs[0].in_off];
        allocib = NULL;
        allocblk = allociblk;

        if (nb == 0) {
                pref = ffs2_blkpref(ip, lbn, -indirs[0].in_off - 1, NULL);
                error = ffs_alloc(ip, lbn, pref, (int) fs->fs_bsize, cred,
                    &newb);
                if (error)
                        goto fail;

                nb = newb;
                *allocblk++ = nb;
                bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, INFSLP);
                bp->b_blkno = fsbtodb(fs, nb);
                clrbuf(bp);

                /*
                 * Write synchronously so that indirect blocks never
                 * point at garbage.
                 */
                error = bwrite(bp);
                if (error)
                        goto fail;

                unwindidx = 0;
                allocib = &ip->i_ffs2_ib[indirs[0].in_off];
                *allocib = nb;
                ip->i_flag |= IN_CHANGE | IN_UPDATE;
        }

        /*
         * Fetch through the indirect blocks, allocating as necessary.
         */
        for (i = 1;;) {
                error = bread(vp, indirs[i].in_lbn, (int)fs->fs_bsize, &bp);
                if (error) {
                        brelse(bp);
                        goto fail;
                }

                bap = (int64_t *) bp->b_data;
                nb = bap[indirs[i].in_off];

                if (i == num)
                        break;

                i++;

                if (nb != 0) {
                        brelse(bp);
                        continue;
                }

                if (pref == 0)
                        pref = ffs2_blkpref(ip, lbn, i - num - 1, NULL);

                error = ffs_alloc(ip, lbn, pref, (int) fs->fs_bsize, cred,
                    &newb);
                if (error) {
                        brelse(bp);
                        goto fail;
                }

                nb = newb;
                *allocblk++ = nb;
                nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, INFSLP);
                nbp->b_blkno = fsbtodb(fs, nb);
                clrbuf(nbp);

                /*
                 * Write synchronously so that indirect blocks never
                 * point at garbage.
                 */
                error = bwrite(nbp);
                if (error) {
                        brelse(bp);
                        goto fail;
                }

                if (unwindidx < 0)
                        unwindidx = i - 1;

                bap[indirs[i - 1].in_off] = nb;

                /*
                 * If required, write synchronously, otherwise use delayed
                 * write.
                 */
                if (flags & B_SYNC)
                        bwrite(bp);
                else
                        bdwrite(bp);
        }

        /*
         * Get the data block, allocating if necessary.
         */
        if (nb == 0) {
                pref = ffs2_blkpref(ip, lbn, indirs[num].in_off, &bap[0]);

                error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred,
                    &newb);
                if (error) {
                        brelse(bp);
                        goto fail;
                }

                nb = newb;
                *allocblk++ = nb;

                if (bpp != NULL) {
                        nbp = getblk(vp, lbn, fs->fs_bsize, 0, INFSLP);
                        nbp->b_blkno = fsbtodb(fs, nb);
                        if (flags & B_CLRBUF)
                                clrbuf(nbp);
                        *bpp = nbp;
                }

                bap[indirs[num].in_off] = nb;

                if (allocib == NULL && unwindidx < 0)
                        unwindidx = i - 1;

                /*
                 * If required, write synchronously, otherwise use delayed
                 * write.
                 */
                if (flags & B_SYNC)
                        bwrite(bp);
                else
                        bdwrite(bp);

                return (0);
        }

        brelse(bp);

        if (bpp != NULL) {
                if (flags & B_CLRBUF) {
                        error = bread(vp, lbn, (int)fs->fs_bsize, &nbp);
                        if (error) {
                                brelse(nbp);
                                goto fail;
                        }
                } else {
                        nbp = getblk(vp, lbn, fs->fs_bsize, 0, INFSLP);
                        nbp->b_blkno = fsbtodb(fs, nb);
                        clrbuf(nbp);
                }

                *bpp = nbp;
        }

        return (0);

fail:
        /*
         * If we have failed to allocate any blocks, simply return the error.
         * This is the usual case and avoids the need to fsync the file.
         */
        if (allocblk == allociblk && allocib == NULL && unwindidx == -1)
                return (error);
        /*
         * If we have failed part way through block allocation, we have to
         * deallocate any indirect blocks that we have allocated. We have to
         * fsync the file before we start to get rid of all of its
         * dependencies so that we do not leave them dangling. We have to sync
         * it at the end so that the softdep code does not find any untracked
         * changes. Although this is really slow, running out of disk space is
         * not expected to be a common occurrence. The error return from fsync
         * is ignored as we already have an error to return to the user.
         */
        VOP_FSYNC(vp, p->p_ucred, MNT_WAIT, p);
        if (unwindidx >= 0) {
                /*
                 * First write out any buffers we've created to resolve their
                 * softdeps. This must be done in reverse order of creation so
                 * that we resolve the dependencies in one pass.
                 * Write the cylinder group buffers for these buffers too.
                 */
                for (i = num; i >= unwindidx; i--) {
                        if (i == 0)
                                break;

                        bp = getblk(vp, indirs[i].in_lbn, (int) fs->fs_bsize,
                            0, INFSLP);
                        if (bp->b_flags & B_DELWRI) {
                                nb = fsbtodb(fs, cgtod(fs, dtog(fs,
                                    dbtofsb(fs, bp->b_blkno))));
                                bwrite(bp);
                                bp = getblk(ip->i_devvp, nb,
                                    (int) fs->fs_cgsize, 0, INFSLP);
                                if (bp->b_flags & B_DELWRI)
                                        bwrite(bp);
                                else {
                                        bp->b_flags |= B_INVAL;
                                        brelse(bp);
                                }
                        } else {
                                bp->b_flags |= B_INVAL;
                                brelse(bp);
                        }
                }

                /*
                 * Now that any dependencies that we created have been
                 * resolved, we can undo the partial allocation.
                 */
                if (unwindidx == 0) {
                        *allocib = 0;
                        ip->i_flag |= IN_CHANGE | IN_UPDATE;
                } else {
                        r = bread(vp, indirs[unwindidx].in_lbn,
                            (int)fs->fs_bsize, &bp);
                        if (r)
                                panic("ffs2_balloc: unwind failed");

                        bap = (int64_t *) bp->b_data;
                        bap[indirs[unwindidx].in_off] = 0;
                        bwrite(bp);
                }

                for (i = unwindidx + 1; i <= num; i++) {
                        bp = getblk(vp, indirs[i].in_lbn, (int)fs->fs_bsize, 0,
                            INFSLP);
                        bp->b_flags |= B_INVAL;
                        brelse(bp);
                }
        }

        for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) {
                ffs_blkfree(ip, *blkp, fs->fs_bsize);
                deallocated += fs->fs_bsize;
        }

        if (deallocated) {
                /*
                 * Restore user's disk quota because allocation failed.
                 */
                (void) ufs_quota_free_blocks(ip, btodb(deallocated), cred);

                ip->i_ffs2_blocks -= btodb(deallocated);
                ip->i_flag |= IN_CHANGE | IN_UPDATE;
        }
        VOP_FSYNC(vp, p->p_ucred, MNT_WAIT, p);
        return (error);
}
#endif /* FFS2 */

/*
 * Balloc defines the structure of file system storage by allocating the
 * physical blocks given the inode and the logical block number in a file.
 */
int
ffs_balloc(struct inode *ip, off_t off, int size, struct ucred *cred,
    int flags, struct buf **bpp)
{
#ifdef FFS2
        if (ip->i_fs->fs_magic == FS_UFS2_MAGIC)
                return (ffs2_balloc(ip, off, size, cred, flags, bpp));
        else
#endif
                return (ffs1_balloc(ip, off, size, cred, flags, bpp));
}