/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rick Macklem at The University of Guelph.
 *
 * 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.
 *
 */

#include <sys/cdefs.h>
/*
 * These functions support the macros and help fiddle mbuf chains for
 * the nfs op functions. They do things like create the rpc header and
 * copy data between mbuf chains and uio lists.
 */
#include <fs/nfs/nfsport.h>

extern struct nfsstatsv1 nfsstatsv1;
extern int ncl_mbuf_mlen;
extern __enum_uint8(vtype) newnv2tov_type[8];
extern __enum_uint8(vtype) nv34tov_type[8];
NFSCLSTATEMUTEX;

/*
 * copies a uio scatter/gather list to an mbuf chain.
 * NOTE: can only handle iovcnt == 1
 */
int
nfsm_uiombuf(struct nfsrv_descript *nd, struct uio *uiop, int siz)
{
        char *uiocp;
        struct mbuf *mp, *mp2;
        int error, xfer, left, mlen;
        int uiosiz, clflg, rem;
        char *mcp, *tcp;

        KASSERT(uiop->uio_iovcnt == 1, ("nfsm_uiotombuf: iovcnt != 1"));

        if (siz > ncl_mbuf_mlen)        /* or should it >= MCLBYTES ?? */
                clflg = 1;
        else
                clflg = 0;
        rem = NFSM_RNDUP(siz) - siz;
        mp = mp2 = nd->nd_mb;
        mcp = nd->nd_bpos;
        while (siz > 0) {
                KASSERT((nd->nd_flag & ND_EXTPG) != 0 || mcp ==
                    mtod(mp, char *) + mp->m_len, ("nfsm_uiombuf: mcp wrong"));
                left = uiop->uio_iov->iov_len;
                uiocp = uiop->uio_iov->iov_base;
                if (left > siz)
                        left = siz;
                uiosiz = left;
                while (left > 0) {
                        if ((nd->nd_flag & ND_EXTPG) != 0)
                                mlen = nd->nd_bextpgsiz;
                        else
                                mlen = M_TRAILINGSPACE(mp);
                        if (mlen == 0) {
                                if ((nd->nd_flag & ND_EXTPG) != 0) {
                                        mp = nfsm_add_ext_pgs(mp,
                                            nd->nd_maxextsiz, &nd->nd_bextpg);
                                        mcp = (char *)(void *)PHYS_TO_DMAP(
                                          mp->m_epg_pa[nd->nd_bextpg]);
                                        nd->nd_bextpgsiz = mlen = PAGE_SIZE;
                                } else {
                                        if (clflg)
                                                NFSMCLGET(mp, M_WAITOK);
                                        else
                                                NFSMGET(mp);
                                        mp->m_len = 0;
                                        mlen = M_TRAILINGSPACE(mp);
                                        mcp = mtod(mp, char *);
                                        mp2->m_next = mp;
                                        mp2 = mp;
                                }
                        }
                        xfer = (left > mlen) ? mlen : left;
                        if (uiop->uio_segflg == UIO_SYSSPACE)
                                NFSBCOPY(uiocp, mcp, xfer);
                        else {
                                error = copyin(uiocp, mcp, xfer);
                                if (error != 0)
                                        return (error);
                        }
                        mp->m_len += xfer;
                        left -= xfer;
                        uiocp += xfer;
                        mcp += xfer;
                        if ((nd->nd_flag & ND_EXTPG) != 0) {
                                nd->nd_bextpgsiz -= xfer;
                                mp->m_epg_last_len += xfer;
                        }
                        uiop->uio_offset += xfer;
                        uiop->uio_resid -= xfer;
                }
                tcp = (char *)uiop->uio_iov->iov_base;
                tcp += uiosiz;
                uiop->uio_iov->iov_base = (void *)tcp;
                uiop->uio_iov->iov_len -= uiosiz;
                siz -= uiosiz;
        }
        if (rem > 0) {
                if ((nd->nd_flag & ND_EXTPG) == 0 && rem >
                    M_TRAILINGSPACE(mp)) {
                        NFSMGET(mp);
                        mp->m_len = 0;
                        mp2->m_next = mp;
                        mcp = mtod(mp, char *);
                } else if ((nd->nd_flag & ND_EXTPG) != 0 && rem >
                    nd->nd_bextpgsiz) {
                        mp = nfsm_add_ext_pgs(mp, nd->nd_maxextsiz,
                            &nd->nd_bextpg);
                        mcp = (char *)(void *)
                            PHYS_TO_DMAP(mp->m_epg_pa[nd->nd_bextpg]);
                        nd->nd_bextpgsiz = PAGE_SIZE;
                }
                for (left = 0; left < rem; left++)
                        *mcp++ = '\0';
                mp->m_len += rem;
                if ((nd->nd_flag & ND_EXTPG) != 0) {
                        nd->nd_bextpgsiz -= rem;
                        mp->m_epg_last_len += rem;
                }
        }
        nd->nd_bpos = mcp;
        nd->nd_mb = mp;
        return (0);
}

/*
 * copies a uio scatter/gather list to an mbuf chain.
 * This version returns the mbuf list and does not use "nd".
 * NOTE: can only handle iovcnt == 1
 */
struct mbuf *
nfsm_uiombuflist(struct uio *uiop, int siz, u_int maxext)
{
        char *uiocp;
        struct mbuf *mp, *mp2, *firstmp;
        int error, extpg, extpgsiz = 0, i, left, mlen, rem, xfer;
        int uiosiz, clflg;
        char *mcp, *tcp;

        KASSERT(uiop->uio_iovcnt == 1, ("nfsm_uiotombuf: iovcnt != 1"));

        if (maxext > 0) {
                mp = mb_alloc_ext_plus_pages(PAGE_SIZE, M_WAITOK);
                mcp = (char *)(void *)PHYS_TO_DMAP(mp->m_epg_pa[0]);
                extpg = 0;
                extpgsiz = PAGE_SIZE;
        } else {
                if (siz > ncl_mbuf_mlen) /* or should it >= MCLBYTES ?? */
                        clflg = 1;
                else
                        clflg = 0;
                if (clflg != 0)
                        NFSMCLGET(mp, M_WAITOK);
                else
                        NFSMGET(mp);
                mcp = mtod(mp, char *);
        }
        mp->m_len = 0;
        firstmp = mp2 = mp;
        rem = NFSM_RNDUP(siz) - siz;
        while (siz > 0) {
                left = uiop->uio_iov->iov_len;
                uiocp = uiop->uio_iov->iov_base;
                if (left > siz)
                        left = siz;
                uiosiz = left;
                while (left > 0) {
                        if (maxext > 0)
                                mlen = extpgsiz;
                        else
                                mlen = M_TRAILINGSPACE(mp);
                        if (mlen == 0) {
                                if (maxext > 0) {
                                        mp = nfsm_add_ext_pgs(mp, maxext,
                                            &extpg);
                                        mlen = extpgsiz = PAGE_SIZE;
                                        mcp = (char *)(void *)PHYS_TO_DMAP(
                                            mp->m_epg_pa[extpg]);
                                } else {
                                        if (clflg)
                                                NFSMCLGET(mp, M_WAITOK);
                                        else
                                                NFSMGET(mp);
                                        mcp = mtod(mp, char *);
                                        mlen = M_TRAILINGSPACE(mp);
                                        mp->m_len = 0;
                                        mp2->m_next = mp;
                                        mp2 = mp;
                                }
                        }
                        xfer = (left > mlen) ? mlen : left;
                        if (uiop->uio_segflg == UIO_SYSSPACE)
                                NFSBCOPY(uiocp, mcp, xfer);
                        else {
                                error = copyin(uiocp, mcp, xfer);
                                if (error != 0) {
                                        m_freem(firstmp);
                                        return (NULL);
                                }
                        }
                        mp->m_len += xfer;
                        mcp += xfer;
                        if (maxext > 0) {
                                extpgsiz -= xfer;
                                mp->m_epg_last_len += xfer;
                        }
                        left -= xfer;
                        uiocp += xfer;
                        uiop->uio_offset += xfer;
                        uiop->uio_resid -= xfer;
                }
                tcp = (char *)uiop->uio_iov->iov_base;
                tcp += uiosiz;
                uiop->uio_iov->iov_base = (void *)tcp;
                uiop->uio_iov->iov_len -= uiosiz;
                siz -= uiosiz;
        }
        if (rem > 0) {
                KASSERT((mp->m_flags & M_EXTPG) != 0 ||
                    rem <= M_TRAILINGSPACE(mp),
                    ("nfsm_uiombuflist: no space for padding"));
                for (i = 0; i < rem; i++)
                        *mcp++ = '\0';
                mp->m_len += rem;
                if (maxext > 0)
                        mp->m_epg_last_len += rem;
        }
        return (firstmp);
}

/*
 * Load vnode attributes from the xdr file attributes.
 * Returns EBADRPC if they can't be parsed, 0 otherwise.
 */
int
nfsm_loadattr(struct nfsrv_descript *nd, struct nfsvattr *nap)
{
        struct nfs_fattr *fp;
        int error = 0;

        if (nd->nd_flag & ND_NFSV4) {
                error = nfsv4_loadattr(nd, NULL, nap, NULL, NULL, 0, NULL,
                    NULL, NULL, NULL, NULL, 0, NULL, NULL, NULL, NULL, NULL,
                    NULL, NULL, NULL);
        } else if (nd->nd_flag & ND_NFSV3) {
                NFSM_DISSECT(fp, struct nfs_fattr *, NFSX_V3FATTR);
                nap->na_type = nfsv34tov_type(fp->fa_type);
                nap->na_mode = fxdr_unsigned(u_short, fp->fa_mode);
                nap->na_rdev = NFSMAKEDEV(
                    fxdr_unsigned(int, fp->fa3_rdev.specdata1),
                    fxdr_unsigned(int, fp->fa3_rdev.specdata2));
                nap->na_nlink = fxdr_unsigned(uint32_t, fp->fa_nlink);
                nap->na_uid = fxdr_unsigned(uid_t, fp->fa_uid);
                nap->na_gid = fxdr_unsigned(gid_t, fp->fa_gid);
                nap->na_size = fxdr_hyper(&fp->fa3_size);
                nap->na_blocksize = NFS_FABLKSIZE;
                nap->na_bytes = fxdr_hyper(&fp->fa3_used);
                nap->na_fileid = fxdr_hyper(&fp->fa3_fileid);
                fxdr_nfsv3time(&fp->fa3_atime, &nap->na_atime);
                fxdr_nfsv3time(&fp->fa3_ctime, &nap->na_ctime);
                fxdr_nfsv3time(&fp->fa3_mtime, &nap->na_mtime);
                nap->na_btime.tv_sec = -1;
                nap->na_btime.tv_nsec = 0;
                nap->na_flags = 0;
                nap->na_gen = 0;
                nap->na_filerev = 0;
        } else {
                NFSM_DISSECT(fp, struct nfs_fattr *, NFSX_V2FATTR);
                nap->na_type = nfsv2tov_type(fp->fa_type);
                nap->na_mode = fxdr_unsigned(u_short, fp->fa_mode);
                if (nap->na_type == VNON || nap->na_type == VREG)
                        nap->na_type = IFTOVT(nap->na_mode);
                nap->na_rdev = fxdr_unsigned(dev_t, fp->fa2_rdev);

                /*
                 * Really ugly NFSv2 kludge.
                 */
                if (nap->na_type == VCHR && nap->na_rdev == ((dev_t)-1))
                        nap->na_type = VFIFO;
                nap->na_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
                nap->na_uid = fxdr_unsigned(uid_t, fp->fa_uid);
                nap->na_gid = fxdr_unsigned(gid_t, fp->fa_gid);
                nap->na_size = fxdr_unsigned(u_int32_t, fp->fa2_size);
                nap->na_blocksize = fxdr_unsigned(int32_t, fp->fa2_blocksize);
                nap->na_bytes =
                    (u_quad_t)fxdr_unsigned(int32_t, fp->fa2_blocks) *
                    NFS_FABLKSIZE;
                nap->na_fileid = fxdr_unsigned(uint64_t, fp->fa2_fileid);
                fxdr_nfsv2time(&fp->fa2_atime, &nap->na_atime);
                fxdr_nfsv2time(&fp->fa2_mtime, &nap->na_mtime);
                nap->na_flags = 0;
                nap->na_ctime.tv_sec = fxdr_unsigned(u_int32_t,
                    fp->fa2_ctime.nfsv2_sec);
                nap->na_ctime.tv_nsec = 0;
                nap->na_btime.tv_sec = -1;
                nap->na_btime.tv_nsec = 0;
                nap->na_gen = fxdr_unsigned(u_int32_t,fp->fa2_ctime.nfsv2_usec);
                nap->na_filerev = 0;
        }
nfsmout:
        return (error);
}

/*
 * Gets a file handle out of an nfs reply sent to the client and returns
 * the file handle and the file's attributes.
 * For V4, it assumes that Getfh and Getattr Op's results are here.
 */
int
nfscl_mtofh(struct nfsrv_descript *nd, struct nfsfh **nfhpp,
    struct nfsvattr *nap, int *attrflagp)
{
        u_int32_t *tl;
        int error = 0, flag = 1;

        *nfhpp = NULL;
        *attrflagp = 0;
        /*
         * First get the file handle and vnode.
         */
        if (nd->nd_flag & ND_NFSV3) {
                NFSM_DISSECT(tl, u_int32_t *, NFSX_UNSIGNED);
                flag = fxdr_unsigned(int, *tl);
        } else if (nd->nd_flag & ND_NFSV4) {
                NFSM_DISSECT(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
                /* If the GetFH failed, clear flag. */
                if (*++tl != 0) {
                        nd->nd_flag |= ND_NOMOREDATA;
                        flag = 0;
                        error = ENXIO;  /* Return ENXIO so *nfhpp isn't used. */
                }
        }
        if (flag) {
                error = nfsm_getfh(nd, nfhpp);
                if (error)
                        return (error);
        }

        /*
         * Now, get the attributes.
         */
        if (flag != 0 && (nd->nd_flag & ND_NFSV4) != 0) {
                NFSM_DISSECT(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
                if (*++tl != 0) {
                        nd->nd_flag |= ND_NOMOREDATA;
                        flag = 0;
                }
        } else if (nd->nd_flag & ND_NFSV3) {
                NFSM_DISSECT(tl, u_int32_t *, NFSX_UNSIGNED);
                if (flag) {
                        flag = fxdr_unsigned(int, *tl);
                } else if (fxdr_unsigned(int, *tl)) {
                        error = nfsm_advance(nd, NFSX_V3FATTR, -1);
                        if (error)
                                return (error);
                }
        }
        if (flag) {
                error = nfsm_loadattr(nd, nap);
                if (!error)
                        *attrflagp = 1;
        }
nfsmout:
        return (error);
}

/*
 * Initialize the owner/delegation sleep lock.
 */
void
nfscl_lockinit(struct nfsv4lock *lckp)
{

        lckp->nfslock_usecnt = 0;
        lckp->nfslock_lock = 0;
}

/*
 * Get an exclusive lock. (Not needed for OpenBSD4, since there is only one
 * thread for each posix process in the kernel.)
 */
void
nfscl_lockexcl(struct nfsv4lock *lckp, void *mutex)
{
        int igotlock;

        do {
                igotlock = nfsv4_lock(lckp, 1, NULL, mutex, NULL);
        } while (!igotlock);
}

/*
 * Release an exclusive lock.
 */
void
nfscl_lockunlock(struct nfsv4lock *lckp)
{

        nfsv4_unlock(lckp, 0);
}

/*
 * Called to dereference a lock on a stateid (delegation or open owner).
 */
void
nfscl_lockderef(struct nfsv4lock *lckp)
{

        NFSLOCKCLSTATE();
        lckp->nfslock_usecnt--;
        if (lckp->nfslock_usecnt == 0 && (lckp->nfslock_lock & NFSV4LOCK_WANTED)) {
                lckp->nfslock_lock &= ~NFSV4LOCK_WANTED;
                wakeup((caddr_t)lckp);
        }
        NFSUNLOCKCLSTATE();
}