* Copyright (c) 2008 Antti Kantee. All Rights Reserved.

/* $NetBSD: rump_vfs.c,v 1.97 2023/09/23 18:21:12 ad Exp $ */

/*
* Copyright (c) 2008 Antti Kantee. All Rights Reserved.
*
* Development of this software was supported by the
* Finnish Cultural Foundation.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rump_vfs.c,v 1.97 2023/09/23 18:21:12 ad Exp $");

#include <sys/param.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/evcnt.h>
#include <sys/fcntl.h>
#include <sys/filedesc.h>
#include <sys/fstrans.h>
#include <sys/lockf.h>
#include <sys/kthread.h>
#include <sys/module.h>
#include <sys/namei.h>
#include <sys/queue.h>
#include <sys/stat.h>
#include <sys/vfs_syscalls.h>
#include <sys/vnode.h>
#include <sys/wapbl.h>
#include <sys/bufq.h>

#include <miscfs/specfs/specdev.h>

#include <rump-sys/kern.h>
#include <rump-sys/vfs.h>

#include <rump/rump.h>
#include <rump/rumpuser.h>

const char *rootfstype = ROOT_FSTYPE_ANY;

static void
pvfs_init(struct proc *p)
{

p->p_cwdi = cwdinit();
}

static void
pvfs_rele(struct proc *p)
{

cwdfree(p->p_cwdi);
}

static void
fini(void)
{

vfs_shutdown();
rumpblk_fini();
}

static void
drainbufs(int npages)
{

mutex_enter(&bufcache_lock);
buf_drain(npages);
mutex_exit(&bufcache_lock);
}

RUMP_COMPONENT(RUMP__FACTION_VFS)
{
extern struct vfsops rumpfs_vfsops;
char buf[64];
char *mbase;
int rv, i;

/* initialize indirect interfaces */
rump_vfs_fini = fini;
rump_vfs_drainbufs = drainbufs;

if (rumpuser_getparam("RUMP_NVNODES", buf, sizeof(buf)) == 0) {
desiredvnodes = strtoul(buf, NULL, 10);
} else {
desiredvnodes = 1<<10;
}

rumpblk_init();

for (i = 0; i < ncpu; i++) {
struct cpu_info *ci = cpu_lookup(i);
cache_cpu_init(ci);
}

/* make number of bufpages 5% of total memory limit */
if (rump_physmemlimit != RUMPMEM_UNLIMITED) {
extern u_int bufpages;
bufpages = rump_physmemlimit / (20 * PAGE_SIZE);
}

bufq_init();
fstrans_init();
vfsinit();
bufinit();
lf_init();
spec_init();

root_device = &rump_rootdev;

/* bootstrap cwdi (rest done in vfs_mountroot() */
proc0.p_cwdi = &cwdi0;
proc0.p_cwdi = cwdinit();

vfs_attach(&rumpfs_vfsops);
vfs_mountroot();

/* "mtree": create /dev and /tmp */
do_sys_mkdir("/dev", 0755, UIO_SYSSPACE);
do_sys_mkdir("/tmp", 01777, UIO_SYSSPACE);
do_sys_chmodat(curlwp, AT_FDCWD, "/tmp", 01777, 0);

rump_proc_vfs_init = pvfs_init;
rump_proc_vfs_release = pvfs_rele;

if (rump_threads) {
if ((rv = kthread_create(PRI_IOFLUSH, KTHREAD_MPSAFE, NULL,
sched_sync, NULL, NULL, "ioflush")) != 0)
panic("syncer thread create failed: %d", rv);
} else {
syncdelay = 0;
}

/*
* On archs where the native kernel ABI is supported, map
* host module directory to rump. This means that kernel
* modules from the host will be autoloaded to rump kernels.
*/
if (rump_nativeabi_p()) {
if (rumpuser_getparam("RUMP_MODULEBASE", buf, sizeof(buf)) == 0)
mbase = buf;
else
mbase = module_base;

if (strlen(mbase) != 0 && *mbase != '0') {
rump_etfs_register(module_base, mbase,
RUMP_ETFS_DIR_SUBDIRS);
}
}

module_init_class(MODULE_CLASS_BUFQ);
module_init_class(MODULE_CLASS_VFS);

/*
* Don't build device names for a large set of devices by
* default. While the pseudo-devfs is a fun experiment,
* creating many many device nodes may increase rump kernel
* bootstrap time by ~40%. Device nodes should be created
* per-demand in the component constructors.
*/
#if 0
{
extern struct devsw_conv devsw_conv0[];
extern int max_devsw_convs;
rump_vfs_builddevs(devsw_conv0, max_devsw_convs);
}
#else
rump_vfs_builddevs(NULL, 0);
#endif

/* attach null device and create /dev/{null,zero} */
rump_devnull_init();

rump_component_init(RUMP_COMPONENT_VFS);
}

struct rumpcn {
struct componentname rcn_cn;
char *rcn_path;
};

struct componentname *
rump_makecn(u_long nameiop, u_long flags, const char *name, size_t namelen,
kauth_cred_t creds, struct lwp *l)
{
struct rumpcn *rcn;
struct componentname *cnp;

rcn = kmem_zalloc(sizeof(*rcn), KM_SLEEP);
cnp = &rcn->rcn_cn;

rcn->rcn_path = PNBUF_GET();
strlcpy(rcn->rcn_path, name, MAXPATHLEN);
cnp->cn_nameptr = rcn->rcn_path;

cnp->cn_nameiop = nameiop;
cnp->cn_flags = flags & (MODMASK | PARAMASK);

cnp->cn_namelen = namelen;

cnp->cn_cred = creds;

return cnp;
}

void
rump_freecn(struct componentname *cnp, int flags)
{
struct rumpcn *rcn = (void *)cnp;

if (flags & RUMPCN_FREECRED)
rump_cred_put(cnp->cn_cred);

PNBUF_PUT(rcn->rcn_path);
kmem_free(rcn, sizeof(*rcn));
}

/* hey baby, what's your namei? */
int
rump_namei(uint32_t op, uint32_t flags, const char *namep,
struct vnode **dvpp, struct vnode **vpp, struct componentname **cnpp)
{
struct pathbuf *pb;
struct nameidata nd;
int rv;

pb = pathbuf_create(namep);
if (pb == NULL) {
return ENOMEM;
}
NDINIT(&nd, op, flags, pb);
rv = namei(&nd);
if (rv) {
pathbuf_destroy(pb);
return rv;
}

if (dvpp) {
KASSERT(flags & LOCKPARENT);
*dvpp = nd.ni_dvp;
} else {
KASSERT((flags & LOCKPARENT) == 0);
}

if (vpp) {
*vpp = nd.ni_vp;
} else {
if (nd.ni_vp) {
if (flags & LOCKLEAF)
vput(nd.ni_vp);
else
vrele(nd.ni_vp);
}
}

if (cnpp) {
struct componentname *cnp;

cnp = kmem_alloc(sizeof(*cnp), KM_SLEEP);
memcpy(cnp, &nd.ni_cnd, sizeof(*cnp));
*cnpp = cnp;
}
pathbuf_destroy(pb);

return rv;
}

void
rump_getvninfo(struct vnode *vp, enum rump_vtype *vtype,
voff_t *vsize, dev_t *vdev)
{

*vtype = (enum rump_vtype)vp->v_type;
*vsize = vp->v_size;
if (vp->v_specnode)
*vdev = vp->v_rdev;
else
*vdev = 0;
}

struct vfsops *
rump_vfslist_iterate(struct vfsops *ops)
{

if (ops == NULL)
return LIST_FIRST(&vfs_list);
else
return LIST_NEXT(ops, vfs_list);
}

struct vfsops *
rump_vfs_getopsbyname(const char *name)
{

return vfs_getopsbyname(name);
}

int
rump_vfs_getmp(const char *path, struct mount **mpp)
{
struct vnode *vp;
int rv;

if ((rv = namei_simple_user(path, NSM_FOLLOW_TRYEMULROOT, &vp)) != 0)
return rv;

*mpp = vp->v_mount;
vrele(vp);
return 0;
}

struct vattr*
rump_vattr_init(void)
{
struct vattr *vap;

vap = kmem_alloc(sizeof(struct vattr), KM_SLEEP);
vattr_null(vap);

return vap;
}

void
rump_vattr_settype(struct vattr *vap, enum rump_vtype vt)
{

vap->va_type = (enum vtype)vt;
}

void
rump_vattr_setmode(struct vattr *vap, mode_t mode)
{

vap->va_mode = mode;
}

void
rump_vattr_setrdev(struct vattr *vap, dev_t dev)
{

vap->va_rdev = dev;
}

void
rump_vattr_free(struct vattr *vap)
{

kmem_free(vap, sizeof(*vap));
}

void
rump_vp_incref(struct vnode *vp)
{

vref(vp);
}

int
rump_vp_getref(struct vnode *vp)
{

return vrefcnt(vp);
}

void
rump_vp_rele(struct vnode *vp)
{

vrele(vp);
}

void
rump_vp_interlock(struct vnode *vp)
{

mutex_enter(vp->v_interlock);
}

void
rump_vp_vmobjlock(struct vnode *vp, int write)
{

rw_enter(vp->v_uobj.vmobjlock, write ? RW_WRITER : RW_READER);
}

int
rump_vfs_unmount(struct mount *mp, int mntflags)
{

return VFS_UNMOUNT(mp, mntflags);
}

int
rump_vfs_root(struct mount *mp, struct vnode **vpp, int lock)
{
int rv;

rv = VFS_ROOT(mp, LK_EXCLUSIVE, vpp);
if (rv)
return rv;

if (!lock)
VOP_UNLOCK(*vpp);

return 0;
}

int
rump_vfs_statvfs(struct mount *mp, struct statvfs *sbp)
{

return VFS_STATVFS(mp, sbp);
}

int
rump_vfs_sync(struct mount *mp, int wait, kauth_cred_t cred)
{

return VFS_SYNC(mp, wait ? MNT_WAIT : MNT_NOWAIT, cred);
}

int
rump_vfs_fhtovp(struct mount *mp, struct fid *fid, struct vnode **vpp)
{

return VFS_FHTOVP(mp, fid, LK_EXCLUSIVE, vpp);
}

int
rump_vfs_vptofh(struct vnode *vp, struct fid *fid, size_t *fidsize)
{

return VFS_VPTOFH(vp, fid, fidsize);
}

int
rump_vfs_extattrctl(struct mount *mp, int cmd, struct vnode *vp,
int attrnamespace, const char *attrname)
{

return VFS_EXTATTRCTL(mp, cmd, vp, attrnamespace, attrname);
}

/*ARGSUSED*/
void
rump_vfs_syncwait(struct mount *mp)
{
int n;

n = vfs_syncwait();
if (n)
printf("syncwait: unsynced buffers: %d\n", n);
}

/*
* Dump info about mount point. No locking.
*/
static bool
rump_print_selector(void *cl, struct vnode *vp)
{
int *full = cl;

KASSERT(mutex_owned(vp->v_interlock));

vfs_vnode_print(vp, *full, (void *)rumpuser_dprintf);
return false;
}

void
rump_vfs_mount_print(const char *path, int full)
{
#ifdef DEBUGPRINT
struct vnode *mvp;
struct vnode_iterator *marker;
int error;

rumpuser_dprintf("\n==== dumping mountpoint at ``%s'' ====\n\n", path);
if ((error = namei_simple_user(path, NSM_FOLLOW_NOEMULROOT, &mvp))!=0) {
rumpuser_dprintf("==== lookup error %d ====\n\n", error);
return;
}
vfs_mount_print(mvp->v_mount, full, (void *)rumpuser_dprintf);
if (full) {
rumpuser_dprintf("\n== dumping vnodes ==\n\n");
vfs_vnode_iterator_init(mvp->v_mount, &marker);
vfs_vnode_iterator_next(marker, rump_print_selector, &full);
vfs_vnode_iterator_destroy(marker);
}
vrele(mvp);
rumpuser_dprintf("\n==== done ====\n\n");
#else
rumpuser_dprintf("mount dump not supported without DEBUGPRINT\n");
#endif
}

void
rump_biodone(void *arg, size_t count, int error)
{
struct buf *bp = arg;

bp->b_resid = bp->b_bcount - count;
KASSERT(bp->b_resid >= 0);
bp->b_error = error;

biodone(bp);
}