/*      $NetBSD: ulfs_inode.c,v 1.26 2020/09/05 16:30:13 riastradh Exp $        */
/*  from NetBSD: ufs_inode.c,v 1.95 2015/06/13 14:56:45 hannken Exp  */

/*
 * Copyright (c) 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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.
 *
 *      @(#)ufs_inode.c 8.9 (Berkeley) 5/14/95
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ulfs_inode.c,v 1.26 2020/09/05 16:30:13 riastradh Exp $");

#if defined(_KERNEL_OPT)
#include "opt_lfs.h"
#include "opt_quota.h"
#include "opt_uvmhist.h"
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/kernel.h>
#include <sys/namei.h>
#include <sys/kauth.h>
#include <sys/kmem.h>

#include <ufs/lfs/lfs.h>
#include <ufs/lfs/lfs_accessors.h>
#include <ufs/lfs/lfs_extern.h>

#include <ufs/lfs/ulfs_inode.h>
#include <ufs/lfs/ulfsmount.h>
#include <ufs/lfs/ulfs_extern.h>
#ifdef LFS_DIRHASH
#include <ufs/lfs/ulfs_dirhash.h>
#endif
#ifdef LFS_EXTATTR
#include <ufs/lfs/ulfs_extattr.h>
#endif

#ifdef UVMHIST
#include <uvm/uvm.h>
#endif
#include <uvm/uvm_page.h>
#include <uvm/uvm_stat.h>

/*
 * Last reference to an inode.  If necessary, write or delete it.
 */
int
ulfs_inactive(void *v)
{
        struct vop_inactive_v2_args /* {
                struct vnode *a_vp;
                struct bool *a_recycle;
        } */ *ap = v;
        struct vnode *vp = ap->a_vp;
        struct inode *ip = VTOI(vp);
        mode_t mode;
        int error = 0;

        /*
         * Ignore inodes related to stale file handles.
         */
        if (ip->i_mode == 0)
                goto out;
        if (ip->i_nlink <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
#ifdef LFS_EXTATTR
                ulfs_extattr_vnode_inactive(vp, curlwp);
#endif
                if (ip->i_size != 0) {
                        error = lfs_truncate(vp, (off_t)0, 0, NOCRED);
                }
#if defined(LFS_QUOTA) || defined(LFS_QUOTA2)
                (void)lfs_chkiq(ip, -1, NOCRED, 0);
#endif
                DIP_ASSIGN(ip, rdev, 0);
                mode = ip->i_mode;
                ip->i_mode = 0;
                ip->i_omode = mode;
                DIP_ASSIGN(ip, mode, 0);
                ip->i_state |= IN_CHANGE | IN_UPDATE;
                /*
                 * Defer final inode free and update to ulfs_reclaim().
                 */
        }

        if (ip->i_state & (IN_CHANGE | IN_UPDATE | IN_MODIFIED)) {
                lfs_update(vp, NULL, NULL, 0);
        }

out:
        /*
         * If we are done with the inode, reclaim it
         * so that it can be reused immediately.
         */
        *ap->a_recycle = (ip->i_mode == 0);

        return (error);
}

/*
 * Reclaim an inode so that it can be used for other purposes.
 */
int
ulfs_reclaim(struct vnode *vp)
{
        struct inode *ip = VTOI(vp);

        /* XXX: do we really need two of these? */
        /* note: originally the first was inside a wapbl txn */
        lfs_update(vp, NULL, NULL, UPDATE_CLOSE);
        lfs_update(vp, NULL, NULL, UPDATE_CLOSE);

        if (ip->i_devvp) {
                vrele(ip->i_devvp);
                ip->i_devvp = 0;
        }
#if defined(LFS_QUOTA) || defined(LFS_QUOTA2)
        ulfsquota_free(ip);
#endif
#ifdef LFS_DIRHASH
        if (ip->i_dirhash != NULL)
                ulfsdirhash_free(ip);
#endif
        return (0);
}

/*
 * allocate a range of blocks in a file.
 * after this function returns, any page entirely contained within the range
 * will map to invalid data and thus must be overwritten before it is made
 * accessible to others.
 */

int
ulfs_balloc_range(struct vnode *vp, off_t off, off_t len, kauth_cred_t cred,
    int flags)
{
        off_t neweof;   /* file size after the operation */
        off_t neweob;   /* offset next to the last block after the operation */
        off_t pagestart; /* starting offset of range covered by pgs */
        off_t eob;      /* offset next to allocated blocks */
        struct uvm_object *uobj;
        int i, delta, error, npages;
        int bshift = vp->v_mount->mnt_fs_bshift;
        int bsize = 1 << bshift;
        int ppb = MAX(bsize >> PAGE_SHIFT, 1);
        struct vm_page **pgs;
        size_t pgssize;
        UVMHIST_FUNC("ulfs_balloc_range"); UVMHIST_CALLED(ubchist);
        UVMHIST_LOG(ubchist, "vp %#jx off 0x%jx len 0x%jx u_size 0x%jx",
                    (uintptr_t)vp, off, len, vp->v_size);

        neweof = MAX(vp->v_size, off + len);
        GOP_SIZE(vp, neweof, &neweob, 0);

        error = 0;
        uobj = &vp->v_uobj;

        /*
         * read or create pages covering the range of the allocation and
         * keep them locked until the new block is allocated, so there
         * will be no window where the old contents of the new block are
         * visible to racing threads.
         */

        pagestart = trunc_page(off) & ~(bsize - 1);
        npages = MIN(ppb, (round_page(neweob) - pagestart) >> PAGE_SHIFT);
        pgssize = npages * sizeof(struct vm_page *);
        pgs = kmem_zalloc(pgssize, KM_SLEEP);

        /*
         * adjust off to be block-aligned.
         */

        delta = off & (bsize - 1);
        off -= delta;
        len += delta;

        genfs_node_wrlock(vp);
        rw_enter(uobj->vmobjlock, RW_WRITER);
        error = VOP_GETPAGES(vp, pagestart, pgs, &npages, 0,
            VM_PROT_WRITE, 0, PGO_SYNCIO | PGO_PASTEOF | PGO_NOBLOCKALLOC |
            PGO_NOTIMESTAMP | PGO_GLOCKHELD);
        if (error) {
                genfs_node_unlock(vp);
                goto out;
        }

        /*
         * now allocate the range.
         */

        error = GOP_ALLOC(vp, off, len, flags, cred);
        genfs_node_unlock(vp);

        /*
         * if the allocation succeeded, mark all pages dirty and clear
         * PG_RDONLY on any pages that are now fully backed by disk blocks. 
         * if the allocation failed, we do not invalidate the pages since
         * they might have already existed and been dirty, in which case we
         * need to keep them around.  if we created the pages, they will be
         * clean and read-only, and leaving such pages in the cache won't
         * cause any problems.
         */

        GOP_SIZE(vp, off + len, &eob, 0);
        rw_enter(uobj->vmobjlock, RW_WRITER);
        for (i = 0; i < npages; i++) {
                KASSERT((pgs[i]->flags & PG_RELEASED) == 0);
                if (!error) {
                        if (off <= pagestart + (i << PAGE_SHIFT) &&
                            pagestart + ((i + 1) << PAGE_SHIFT) <= eob) {
                                pgs[i]->flags &= ~PG_RDONLY;
                        }
                        uvm_pagemarkdirty(pgs[i], UVM_PAGE_STATUS_DIRTY);
                }
                uvm_pagelock(pgs[i]);
                uvm_pageactivate(pgs[i]);
                uvm_pageunlock(pgs[i]);
        }
        uvm_page_unbusy(pgs, npages);
        rw_exit(uobj->vmobjlock);

 out:
        kmem_free(pgs, pgssize);
        return error;
}