/*      $OpenBSD: ext2fs_inode.c,v 1.68 2024/07/13 14:37:56 beck Exp $  */
/*      $NetBSD: ext2fs_inode.c,v 1.24 2001/06/19 12:59:18 wiz Exp $    */

/*
 * Copyright (c) 1997 Manuel Bouyer.
 * 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_inode.c 8.8 (Berkeley) 10/19/94
 * Modified for ext2fs by Manuel Bouyer.
 */

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

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

#include <ufs/ext2fs/ext2fs.h>
#include <ufs/ext2fs/ext2fs_extern.h>

static int ext2fs_indirtrunc(struct inode *, int32_t, int32_t,
                                int32_t, int, long *);

/*
 * Get the size of an inode.
 */
u_int64_t
ext2fs_size(struct inode *ip)
{
        u_int64_t size = ip->i_e2fs_size;

        if ((ip->i_e2fs_mode & IFMT) == IFREG)
                size |= (u_int64_t)ip->i_e2fs_size_hi << 32;

        return (size);
}

int
ext2fs_setsize(struct inode *ip, u_int64_t size)
{
        struct m_ext2fs *fs = ip->i_e2fs;

        if (size <= fs->e2fs_maxfilesize) {
                /* If HUGE_FILEs are off, e2fs_maxfilesize will protect us. */
                if ((ip->i_e2fs_mode & IFMT) == IFREG || ip->i_e2fs_mode == 0)
                        ip->i_e2fs_size_hi = size >> 32;

                ip->i_e2fs_size = size;
                return (0);
        }

        /* Linux automagically upgrades to REV1 here! */
        if (fs->e2fs.e2fs_rev <= E2FS_REV0)
                return (EFBIG);

        if (!(fs->e2fs.e2fs_features_rocompat & EXT2F_ROCOMPAT_LARGE_FILE)) {
                fs->e2fs.e2fs_features_rocompat |= EXT2F_ROCOMPAT_LARGE_FILE;
                fs->e2fs_fmod = 1;
        }
        return (EFBIG);
}


/*
 * Last reference to an inode.  If necessary, write or delete it.
 */
int
ext2fs_inactive(void *v)
{
        struct vop_inactive_args *ap = v;
        struct vnode *vp = ap->a_vp;
        struct inode *ip = VTOI(vp);
        struct timespec ts;
        int error = 0;
#ifdef DIAGNOSTIC
        extern int prtactive;

        if (prtactive && vp->v_usecount != 0)
                vprint("ext2fs_inactive: pushing active", vp);
#endif

        /* Get rid of inodes related to stale file handles. */
        if (ip->i_e2din == NULL || ip->i_e2fs_mode == 0 || ip->i_e2fs_dtime)
                goto out;

        error = 0;
        if (ip->i_e2fs_nlink == 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
                if (ext2fs_size(ip) != 0) {
                        error = ext2fs_truncate(ip, (off_t)0, 0, NOCRED);
                }
                getnanotime(&ts);
                ip->i_e2fs_dtime = ts.tv_sec;
                ip->i_flag |= IN_CHANGE | IN_UPDATE;
                ext2fs_inode_free(ip, ip->i_number, ip->i_e2fs_mode);
        }
        if (ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) {
                ext2fs_update(ip, 0);
        }
out:
        VOP_UNLOCK(vp);
        /*
         * If we are done with the inode, reclaim it
         * so that it can be reused immediately.
         */
        if (ip->i_e2din == NULL || ip->i_e2fs_dtime != 0)
                vrecycle(vp, ap->a_p);
        return (error);
}


/*
 * Update the access, modified, and inode change times as specified by the
 * IACCESS, IUPDATE, and ICHANGE flags respectively. The IMODIFIED flag is
 * used to specify that the inode needs to be updated but that the times have
 * already been set. The access and modified times are taken from the second
 * and third parameters; the inode change time is always taken from the current
 * time. If waitfor is set, then wait for the disk write of the inode to
 * complete.
 */
int
ext2fs_update(struct inode *ip, int waitfor)
{
        struct m_ext2fs *fs;
        struct buf *bp;
        int error;
        caddr_t cp;

        if (ITOV(ip)->v_mount->mnt_flag & MNT_RDONLY)
                return (0);
        EXT2FS_ITIMES(ip);
        if ((ip->i_flag & IN_MODIFIED) == 0)
                return (0);
        ip->i_flag &= ~IN_MODIFIED;
        fs = ip->i_e2fs;
        error = bread(ip->i_devvp,
                          fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
                          (int)fs->e2fs_bsize, &bp);
        if (error) {
                brelse(bp);
                return (error);
        }
        ip->i_flag &= ~(IN_MODIFIED);
        cp = (caddr_t)bp->b_data +
            (ino_to_fsbo(fs, ip->i_number) * EXT2_DINODE_SIZE(fs));

        /*
         * See note about 16-bit UID/GID limitation in ext2fs_vget(). Now
         * that we are about to write the inode, construct the split UID and
         * GID fields out of the two 32-bit fields we kept in memory.
         */
        ip->i_e2fs_uid_low = (u_int16_t)ip->i_e2fs_uid;
        ip->i_e2fs_gid_low = (u_int16_t)ip->i_e2fs_gid;
        ip->i_e2fs_uid_high = ip->i_e2fs_uid >> 16;
        ip->i_e2fs_gid_high = ip->i_e2fs_gid >> 16;

        e2fs_isave(fs, ip->i_e2din, (struct ext2fs_dinode *)cp);
        if (waitfor)
                return (bwrite(bp));
        else {
                bdwrite(bp);
                return (0);
        }
}

#define SINGLE  0       /* index of single indirect block */
#define DOUBLE  1       /* index of double indirect block */
#define TRIPLE  2       /* index of triple indirect block */
/*
 * Truncate the inode oip to at most length size, freeing the
 * disk blocks.
 */
int
ext2fs_truncate(struct inode *oip, off_t length, int flags, struct ucred *cred)
{
        struct vnode *ovp = ITOV(oip);
        int32_t lastblock;
        int32_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
        int32_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
        struct m_ext2fs *fs;
        struct buf *bp;
        int offset, size, level;
        long count, nblocks, vflags, blocksreleased = 0;
        int i;
        int aflags, error, allerror;
        off_t osize;

        if (length < 0)
                return (EINVAL);

        if (ovp->v_type != VREG &&
            ovp->v_type != VDIR &&
            ovp->v_type != VLNK)
                return (0);

        if (ovp->v_type == VLNK && ext2fs_size(oip) < EXT2_MAXSYMLINKLEN) {
#ifdef DIAGNOSTIC
                if (length != 0)
                        panic("ext2fs_truncate: partial truncate of symlink");
#endif
                memset(&oip->i_e2din->e2di_shortlink, 0, ext2fs_size(oip));
                (void)ext2fs_setsize(oip, 0);
                oip->i_flag |= IN_CHANGE | IN_UPDATE;
                return (ext2fs_update(oip, 1));
        }

        if (ext2fs_size(oip) == length) {
                oip->i_flag |= IN_CHANGE | IN_UPDATE;
                return (ext2fs_update(oip, 0));
        }
        fs = oip->i_e2fs;
        osize = ext2fs_size(oip);
        /*
         * Lengthen the size of the file. We must ensure that the
         * last byte of the file is allocated. Since the smallest
         * value of osize is 0, length will be at least 1.
         */
        if (osize < length) {
#if 0 /* XXX */
                if (length > fs->fs_maxfilesize)
                        return (EFBIG);
#endif
                offset = blkoff(fs, length - 1);
                lbn = lblkno(fs, length - 1);
                aflags = B_CLRBUF;
                if (flags & IO_SYNC)
                        aflags |= B_SYNC;
                error = ext2fs_buf_alloc(oip, lbn, offset + 1, cred, &bp,
                    aflags);
                if (error)
                        return (error);
                (void)ext2fs_setsize(oip, length);
                uvm_vnp_setsize(ovp, length);
                uvm_vnp_uncache(ovp);
                if (aflags & B_SYNC)
                        bwrite(bp);
                else
                        bawrite(bp);
                oip->i_flag |= IN_CHANGE | IN_UPDATE;
                return (ext2fs_update(oip, 1));
        }
        /*
         * Shorten the size of the file. If the file is not being
         * truncated to a block boundary, the contents of the
         * partial block following the end of the file must be
         * zero'ed in case it ever become accessible again because
         * of subsequent file growth.
         */
        offset = blkoff(fs, length);
        if (offset == 0) {
                (void)ext2fs_setsize(oip, length);
        } else {
                lbn = lblkno(fs, length);
                aflags = B_CLRBUF;
                if (flags & IO_SYNC)
                        aflags |= B_SYNC;
                error = ext2fs_buf_alloc(oip, lbn, offset, cred, &bp,
                    aflags);
                if (error)
                        return (error);
                (void)ext2fs_setsize(oip, length);
                size = fs->e2fs_bsize;
                uvm_vnp_setsize(ovp, length);
                uvm_vnp_uncache(ovp);
                memset(bp->b_data + offset, 0, size - offset);
                bp->b_bcount = size;
                if (aflags & B_SYNC)
                        bwrite(bp);
                else
                        bawrite(bp);
        }
        /*
         * Calculate index into inode's block list of
         * last direct and indirect blocks (if any)
         * which we want to keep.  Lastblock is -1 when
         * the file is truncated to 0.
         */
        lastblock = lblkno(fs, length + fs->e2fs_bsize - 1) - 1;
        lastiblock[SINGLE] = lastblock - NDADDR;
        lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
        lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
        nblocks = btodb(fs->e2fs_bsize);
        /*
         * Update file and block pointers on disk before we start freeing
         * blocks.  If we crash before free'ing blocks below, the blocks
         * will be returned to the free list.  lastiblock values are also
         * normalized to -1 for calls to ext2fs_indirtrunc below.
         */
        memcpy(oldblks, &oip->i_e2fs_blocks[0], sizeof(oldblks));
        for (level = TRIPLE; level >= SINGLE; level--)
                if (lastiblock[level] < 0) {
                        oip->i_e2fs_blocks[NDADDR + level] = 0;
                        lastiblock[level] = -1;
                }
        for (i = NDADDR - 1; i > lastblock; i--)
                oip->i_e2fs_blocks[i] = 0;
        oip->i_flag |= IN_CHANGE | IN_UPDATE;
        if ((error = ext2fs_update(oip, 1)) != 0)
                allerror = error;
        /*
         * Having written the new inode to disk, save its new configuration
         * and put back the old block pointers long enough to process them.
         * Note that we save the new block configuration so we can check it
         * when we are done.
         */
        memcpy(newblks, &oip->i_e2fs_blocks[0], sizeof(newblks));
        memcpy(&oip->i_e2fs_blocks[0], oldblks, sizeof(oldblks));
        (void)ext2fs_setsize(oip, osize);
        vflags = ((length > 0) ? V_SAVE : 0) | V_SAVEMETA;
        allerror = vinvalbuf(ovp, vflags, cred, curproc, 0, INFSLP);

        /*
         * Indirect blocks first.
         */
        indir_lbn[SINGLE] = -NDADDR;
        indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) -1;
        indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
        for (level = TRIPLE; level >= SINGLE; level--) {
                bn = letoh32(oip->i_e2fs_blocks[NDADDR + level]);
                if (bn != 0) {
                        error = ext2fs_indirtrunc(oip, indir_lbn[level],
                            fsbtodb(fs, bn), lastiblock[level], level, &count);
                        if (error)
                                allerror = error;
                        blocksreleased += count;
                        if (lastiblock[level] < 0) {
                                oip->i_e2fs_blocks[NDADDR + level] = 0;
                                ext2fs_blkfree(oip, bn);
                                blocksreleased += nblocks;
                        }
                }
                if (lastiblock[level] >= 0)
                        goto done;
        }

        /*
         * All whole direct blocks or frags.
         */
        for (i = NDADDR - 1; i > lastblock; i--) {
                bn = letoh32(oip->i_e2fs_blocks[i]);
                if (bn == 0)
                        continue;
                oip->i_e2fs_blocks[i] = 0;
                ext2fs_blkfree(oip, bn);
                blocksreleased += btodb(fs->e2fs_bsize);
        }

done:
#ifdef DIAGNOSTIC
        for (level = SINGLE; level <= TRIPLE; level++)
                if (newblks[NDADDR + level] !=
                    oip->i_e2fs_blocks[NDADDR + level])
                        panic("ext2fs_truncate1");
        for (i = 0; i < NDADDR; i++)
                if (newblks[i] != oip->i_e2fs_blocks[i])
                        panic("ext2fs_truncate2");
        if (length == 0) {
                int s;

                s = splbio();
                if (!LIST_EMPTY(&ovp->v_cleanblkhd) ||
                    !LIST_EMPTY(&ovp->v_dirtyblkhd))
                        panic("ext2fs_truncate3");
                splx(s);
        }
#endif /* DIAGNOSTIC */
        /*
         * Put back the real size.
         */
        (void)ext2fs_setsize(oip, length);
        if (blocksreleased >= oip->i_e2fs_nblock)
                oip->i_e2fs_nblock = 0;
        else
                oip->i_e2fs_nblock -= blocksreleased;
        oip->i_flag |= IN_CHANGE;
        return (allerror);
}

/*
 * Release blocks associated with the inode ip and stored in the indirect
 * block bn.  Blocks are free'd in LIFO order up to (but not including)
 * lastbn.  If level is greater than SINGLE, the block is an indirect block
 * and recursive calls to indirtrunc must be used to cleanse other indirect
 * blocks.
 *
 * NB: triple indirect blocks are untested.
 */
static int
ext2fs_indirtrunc(struct inode *ip, int32_t lbn, int32_t dbn, int32_t lastbn, int level, long *countp)
{
        int i;
        struct buf *bp;
        struct m_ext2fs *fs = ip->i_e2fs;
        int32_t *bap;
        struct vnode *vp;
        int32_t *copy = NULL, nb, nlbn, last;
        long blkcount, factor;
        int nblocks, blocksreleased = 0;
        int error = 0, allerror = 0;

        /*
         * Calculate index in current block of last
         * block to be kept.  -1 indicates the entire
         * block so we need not calculate the index.
         */
        factor = 1;
        for (i = SINGLE; i < level; i++)
                factor *= NINDIR(fs);
        last = lastbn;
        if (lastbn > 0)
                last /= factor;
        nblocks = btodb(fs->e2fs_bsize);
        /*
         * Get buffer of block pointers, zero those entries corresponding
         * to blocks to be free'd, and update on disk copy first.  Since
         * double(triple) indirect before single(double) indirect, calls
         * to bmap on these blocks will fail.  However, we already have
         * the on disk address, so we have to set the b_blkno field
         * explicitly instead of letting bread do everything for us.
         */
        vp = ITOV(ip);
        bp = getblk(vp, lbn, (int)fs->e2fs_bsize, 0, INFSLP);
        if (!(bp->b_flags & (B_DONE | B_DELWRI))) {
                curproc->p_ru.ru_inblock++;             /* pay for read */
                bcstats.pendingreads++;
                bcstats.numreads++;
                bp->b_flags |= B_READ;
                if (bp->b_bcount > bp->b_bufsize)
                        panic("ext2fs_indirtrunc: bad buffer size");
                bp->b_blkno = dbn;
                VOP_STRATEGY(bp->b_vp, bp);
                error = biowait(bp);
        }
        if (error) {
                brelse(bp);
                *countp = 0;
                return (error);
        }

        bap = (int32_t *)bp->b_data;
        if (lastbn >= 0) {
                copy = malloc(fs->e2fs_bsize, M_TEMP, M_WAITOK);
                memcpy(copy, bap, fs->e2fs_bsize);
                memset(&bap[last + 1], 0,
                    (NINDIR(fs) - (last + 1)) * sizeof(u_int32_t));
                error = bwrite(bp);
                if (error)
                        allerror = error;
                bap = copy;
        }

        /*
         * Recursively free totally unused blocks.
         */
        for (i = NINDIR(fs) - 1,
                nlbn = lbn + 1 - i * factor; i > last;
                i--, nlbn += factor) {
                nb = letoh32(bap[i]);
                if (nb == 0)
                        continue;
                if (level > SINGLE) {
                        error = ext2fs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
                                                   (int32_t)-1, level - 1,
                                                   &blkcount);
                        if (error)
                                allerror = error;
                        blocksreleased += blkcount;
                }
                ext2fs_blkfree(ip, nb);
                blocksreleased += nblocks;
        }

        /*
         * Recursively free last partial block.
         */
        if (level > SINGLE && lastbn >= 0) {
                last = lastbn % factor;
                nb = letoh32(bap[i]);
                if (nb != 0) {
                        error = ext2fs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
                                                   last, level - 1, &blkcount);
                        if (error)
                                allerror = error;
                        blocksreleased += blkcount;
                }
        }

        if (copy != NULL) {
                free(copy, M_TEMP, fs->e2fs_bsize);
        } else {
                bp->b_flags |= B_INVAL;
                brelse(bp);
        }

        *countp = blocksreleased;
        return (allerror);
}