/*	$NetBSD: smbfs_vfsops.c,v 1.70 2007/07/31 21:14:18 pooka Exp $	*/

/*
 * Copyright (c) 2000-2001, Boris Popov
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by Boris Popov.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 * FreeBSD: src/sys/fs/smbfs/smbfs_vfsops.c,v 1.5 2001/12/13 13:08:34 sheldonh Exp
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: smbfs_vfsops.c,v 1.70 2007/07/31 21:14:18 pooka Exp $");

#ifdef _KERNEL_OPT
#include "opt_quota.h"
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/kernel.h>
#include <sys/dirent.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/malloc.h>
#include <sys/kauth.h>


#include <netsmb/smb.h>
#include <netsmb/smb_conn.h>
#include <netsmb/smb_subr.h>
#include <netsmb/smb_dev.h>

#include <fs/smbfs/smbfs.h>
#include <fs/smbfs/smbfs_node.h>
#include <fs/smbfs/smbfs_subr.h>

#ifndef __NetBSD__
SYSCTL_NODE(_vfs, OID_AUTO, smbfs, CTLFLAG_RW, 0, "SMB/CIFS file system");
SYSCTL_INT(_vfs_smbfs, OID_AUTO, version, CTLFLAG_RD, &smbfs_version, 0, "");
#else
SYSCTL_SETUP(sysctl_vfs_samba_setup, "sysctl vfs.samba subtree setup")
{
	const struct sysctlnode *smb = NULL;

	sysctl_createv(clog, 0, NULL, NULL,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_NODE, "vfs", NULL,
		       NULL, 0, NULL, 0,
		       CTL_VFS, CTL_EOL);
	sysctl_createv(clog, 0, NULL, &smb,
		       CTLFLAG_PERMANENT,
		       CTLTYPE_NODE, "samba",
		       SYSCTL_DESCR("SMB/CIFS remote file system"),
		       NULL, 0, NULL, 0,
		       CTL_VFS, CTL_CREATE, CTL_EOL);

	if (smb != NULL)
		sysctl_createv(clog, 0, &smb, NULL,
			       CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
			       CTLTYPE_INT, "version",
			       SYSCTL_DESCR("smbfs version"),
			       NULL, SMBFS_VERSION, NULL, 0,
			       CTL_CREATE, CTL_EOL);
}
#endif

static MALLOC_JUSTDEFINE(M_SMBFSHASH, "SMBFS hash", "SMBFS hash table");

VFS_PROTOS(smbfs);

static int smbfs_setroot(struct mount *);

struct pool smbfs_node_pool;
extern struct vnodeopv_desc smbfs_vnodeop_opv_desc;

static const struct vnodeopv_desc *smbfs_vnodeopv_descs[] = {
	&smbfs_vnodeop_opv_desc,
	NULL,
};

struct vfsops smbfs_vfsops = {
	MOUNT_SMBFS,
	sizeof (struct smbfs_args),
	smbfs_mount,
	smbfs_start,
	smbfs_unmount,
	smbfs_root,
	smbfs_quotactl,
	smbfs_statvfs,
	smbfs_sync,
	smbfs_vget,
	(void *)eopnotsupp,	/* vfs_fhtovp */
	(void *)eopnotsupp,	/* vfs_vptofh */
	smbfs_init,
	smbfs_reinit,
	smbfs_done,
	(int (*) (void)) eopnotsupp, /* mountroot */
	(int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp,
	vfs_stdextattrctl,
	(void *)eopnotsupp,	/* vfs_suspendctl */
	smbfs_vnodeopv_descs,
	0,			/* vfs_refcount */
	{ NULL, NULL },
};
VFS_ATTACH(smbfs_vfsops);

int
smbfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len,
    struct lwp *l)
{
	struct smbfs_args *args = data; 	  /* holds data from mount request */
	struct smbmount *smp = NULL;
	struct smb_vc *vcp;
	struct smb_share *ssp = NULL;
	struct smb_cred scred;
	struct proc *p;
	int error;

	if (*data_len < sizeof *args)
		return EINVAL;

	p = l->l_proc;
	if (mp->mnt_flag & MNT_GETARGS) {
		smp = VFSTOSMBFS(mp);
		if (smp == NULL)
			return EIO;
		*args = smp->sm_args;
		*data_len = sizeof *args;
		return 0;
	}

	if (mp->mnt_flag & MNT_UPDATE)
		return EOPNOTSUPP;

	if (args->version != SMBFS_VERSION) {
		SMBVDEBUG("mount version mismatch: kernel=%d, mount=%d\n",
		    SMBFS_VERSION, args->version);
		return EINVAL;
	}
	smb_makescred(&scred, l, l->l_cred);
	error = smb_dev2share(args->dev_fd, SMBM_EXEC, &scred, &ssp);
	if (error)
		return error;
	smb_share_unlock(ssp, 0);	/* keep ref, but unlock */
	vcp = SSTOVC(ssp);
	mp->mnt_stat.f_iosize = vcp->vc_txmax;
	mp->mnt_stat.f_namemax =
	    (vcp->vc_hflags2 & SMB_FLAGS2_KNOWS_LONG_NAMES) ? 255 : 12;

	MALLOC(smp, struct smbmount *, sizeof(*smp), M_SMBFSDATA, M_WAITOK);
	memset(smp, 0, sizeof(*smp));
	mp->mnt_data = smp;

	smp->sm_hash = hashinit(desiredvnodes, HASH_LIST,
				M_SMBFSHASH, M_WAITOK, &smp->sm_hashlen);

	lockinit(&smp->sm_hashlock, PVFS, "smbfsh", 0, 0);
	smp->sm_share = ssp;
	smp->sm_root = NULL;
	smp->sm_args = *args;
	smp->sm_caseopt = args->caseopt;
	smp->sm_args.file_mode = (smp->sm_args.file_mode &
			    (S_IRWXU|S_IRWXG|S_IRWXO)) | S_IFREG;
	smp->sm_args.dir_mode  = (smp->sm_args.dir_mode &
			    (S_IRWXU|S_IRWXG|S_IRWXO)) | S_IFDIR;

	error = set_statvfs_info(path, UIO_USERSPACE, NULL, UIO_USERSPACE,
	    mp->mnt_op->vfs_name, mp, l);
	if (error)
		goto bad;
	memset(mp->mnt_stat.f_mntfromname, 0, MNAMELEN);
	snprintf(mp->mnt_stat.f_mntfromname, MNAMELEN,
	    "//%s@%s/%s", vcp->vc_username, vcp->vc_srvname, ssp->ss_name);

	vfs_getnewfsid(mp);
	return (0);

bad:
	if (smp) {
		if (smp->sm_hash)
			free(smp->sm_hash, M_SMBFSHASH);
#ifdef __NetBSD__
		lockmgr(&smp->sm_hashlock, LK_DRAIN, NULL);
#else
		lockdestroy(&smp->sm_hashlock);
#endif
		FREE(smp, M_SMBFSDATA);
	}
	if (ssp) {
		smb_share_lock(smp->sm_share, 0);
		smb_share_put(ssp, &scred);
	}
	return error;
}

/* Unmount the filesystem described by mp. */
int
smbfs_unmount(struct mount *mp, int mntflags, struct lwp *l)
{
	struct smbmount *smp = VFSTOSMBFS(mp);
	struct smb_cred scred;
	int error, flags;

	SMBVDEBUG("smbfs_unmount: flags=%04x\n", mntflags);
	flags = 0;
	if (mntflags & MNT_FORCE)
		flags |= FORCECLOSE;
#ifdef QUOTA
#endif
	/* Drop the extra reference to root vnode. */
	if (smp->sm_root) {
		vrele(SMBTOV(smp->sm_root));
		smp->sm_root = NULL;
	}

	/* Flush all vnodes.
	 * Keep trying to flush the vnode list for the mount while 
	 * some are still busy and we are making progress towards
	 * making them not busy. This is needed because smbfs vnodes
	 * reference their parent directory but may appear after their
	 * parent in the list; one pass over the vnode list is not
	 * sufficient in this case. */
	do {
		smp->sm_didrele = 0;
		error = vflush(mp, NULLVP, flags);
	} while (error == EBUSY && smp->sm_didrele != 0);

	smb_makescred(&scred, l, l->l_cred);
	smb_share_lock(smp->sm_share, 0);
	smb_share_put(smp->sm_share, &scred);
	mp->mnt_data = NULL;

	free(smp->sm_hash, M_SMBFSHASH);
#ifdef __NetBSD__
	lockmgr(&smp->sm_hashlock, LK_DRAIN, NULL);
#else
	lockdestroy(&smp->sm_hashlock);
#endif
	FREE(smp, M_SMBFSDATA);
	return error;
}

/*
 * Get root vnode of the smbfs filesystem, and store it in sm_root.
 */
static int
smbfs_setroot(struct mount *mp)
{
	struct smbmount *smp = VFSTOSMBFS(mp);
	struct vnode *vp;
	struct smbfattr fattr;
	struct lwp *l = curlwp;
	kauth_cred_t cred = l->l_cred;
	struct smb_cred scred;
	int error;

	KASSERT(smp->sm_root == NULL);

	smb_makescred(&scred, l, cred);
	error = smbfs_smb_lookup(NULL, NULL, 0, &fattr, &scred);
	if (error)
		return error;
	error = smbfs_nget(mp, NULL, "TheRooT", 7, &fattr, &vp);
	if (error)
		return error;

	/*
	 * Someone might have already set sm_root while we slept
	 * in smb_lookup or malloc/getnewvnode.
	 */
	if (smp->sm_root)
		vput(vp);
	else {
		vp->v_flag |= VROOT;
		smp->sm_root = VTOSMB(vp);

		/* Keep reference, but unlock */
		VOP_UNLOCK(vp, 0);
	}

	return (0);
}

/*
 * Return locked root vnode of a filesystem.
 */
int
smbfs_root(struct mount *mp, struct vnode **vpp)
{
	struct smbmount *smp = VFSTOSMBFS(mp);

	if (__predict_false(!smp->sm_root)) {
		int error = smbfs_setroot(mp);
		if (error)
			return (error);
		/* fallthrough */
	}

	KASSERT(smp->sm_root != NULL && SMBTOV(smp->sm_root) != NULL);
	*vpp = SMBTOV(smp->sm_root);
	return vget(*vpp, LK_EXCLUSIVE | LK_RETRY);
}

/*
 * Make a filesystem operational.
 * Nothing to do at the moment.
 */
/* ARGSUSED */
int
smbfs_start(struct mount *mp, int flags,
    struct lwp *l)
{
	SMBVDEBUG("flags=%04x\n", flags);
	return 0;
}

/*
 * Do operations associated with quotas, not supported
 */
/* ARGSUSED */
int
smbfs_quotactl(struct mount *mp, int cmd, uid_t uid,
    void *arg, struct lwp *l)
{
	SMBVDEBUG("return EOPNOTSUPP\n");
	return EOPNOTSUPP;
}

void
smbfs_init(void)
{

	malloc_type_attach(M_SMBNODENAME);
	malloc_type_attach(M_SMBFSDATA);
	malloc_type_attach(M_SMBFSHASH);
	pool_init(&smbfs_node_pool, sizeof(struct smbnode), 0, 0, 0,
	    "smbfsnopl", &pool_allocator_nointr, IPL_NONE);

	SMBVDEBUG("init.\n");
}

void
smbfs_reinit(void)
{

	SMBVDEBUG("reinit.\n");
}

void
smbfs_done(void)
{

	pool_destroy(&smbfs_node_pool);

	pool_destroy(&smbfs_node_pool);
	malloc_type_detach(M_SMBNODENAME);
	malloc_type_detach(M_SMBFSDATA);
	malloc_type_detach(M_SMBFSHASH);

	SMBVDEBUG("done.\n");
}

/*
 * smbfs_statvfs call
 */
int
smbfs_statvfs(struct mount *mp, struct statvfs *sbp, struct lwp *l)
{
	struct smbmount *smp = VFSTOSMBFS(mp);
	struct smb_share *ssp = smp->sm_share;
	struct smb_cred scred;
	int error = 0;

	sbp->f_iosize = SSTOVC(ssp)->vc_txmax;		/* optimal transfer block size */
	smb_makescred(&scred, l, l->l_cred);

	error = smbfs_smb_statvfs(ssp, sbp, &scred);
	if (error)
		return error;

	sbp->f_flag = 0;		/* copy of mount exported flags */
	sbp->f_owner = mp->mnt_stat.f_owner;	/* user that mounted the filesystem */
	copy_statvfs_info(sbp, mp);
	return 0;
}

/*
 * Flush out the buffer cache
 */
int
smbfs_sync(struct mount *mp, int waitfor, kauth_cred_t cred, struct lwp *l)
{
	struct vnode *vp, *nvp;
	struct smbnode *np;
	int error, allerror = 0;
	/*
	 * Force stale buffer cache information to be flushed.
	 */
	simple_lock(&mntvnode_slock);
loop:
	/*
	 * NOTE: not using the TAILQ_FOREACH here since in this loop vgone()
	 * and vclean() can be called indirectly
	 */
	for (vp = TAILQ_FIRST(&mp->mnt_vnodelist); vp; vp = nvp) {
		/*
		 * If the vnode that we are about to sync is no longer
		 * associated with this mount point, start over.
		 */
		if (vp->v_mount != mp)
			goto loop;
		simple_lock(&vp->v_interlock);
		nvp = TAILQ_NEXT(vp, v_mntvnodes);

		np = VTOSMB(vp);
		if (np == NULL) {
			simple_unlock(&vp->v_interlock);
			continue;
		}
			
		if ((vp->v_type == VNON || (np->n_flag & NMODIFIED) == 0) &&
		    LIST_EMPTY(&vp->v_dirtyblkhd) &&
		     UVM_OBJ_IS_CLEAN(&vp->v_uobj)) {
			simple_unlock(&vp->v_interlock);
			continue;
		}
		simple_unlock(&mntvnode_slock);
		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK);
		if (error) {
			simple_lock(&mntvnode_slock);
			if (error == ENOENT)
				goto loop;
			continue;
		}
		error = VOP_FSYNC(vp, cred,
		    waitfor == MNT_WAIT ? FSYNC_WAIT : 0, 0, 0, l);
		if (error)
			allerror = error;
		vput(vp);
		simple_lock(&mntvnode_slock);
	}
	simple_unlock(&mntvnode_slock);
	return (allerror);
}

#if __FreeBSD_version < 400009
/*
 * smbfs flat namespace lookup. Unsupported.
 */
/* ARGSUSED */
int smbfs_vget(struct mount *mp, ino_t ino,
    struct vnode **vpp)
{
	return (EOPNOTSUPP);
}

#endif /* __FreeBSD_version < 400009 */