ctfs_root.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/modctl.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/cred.h>
#include <sys/vfs.h>
#include <sys/gfs.h>
#include <sys/vnode.h>
#include <sys/systm.h>
#include <sys/cmn_err.h>
#include <sys/errno.h>
#include <sys/sysmacros.h>
#include <sys/policy.h>
#include <sys/mount.h>
#include <sys/pathname.h>
#include <sys/dirent.h>
#include <fs/fs_subr.h>
#include <sys/contract.h>
#include <sys/contract_impl.h>
#include <sys/ctfs.h>
#include <sys/ctfs_impl.h>
#include <sys/uio.h>
#include <sys/file.h>
#include <sys/atomic.h>
#include <sys/sunddi.h>
/*
* ctfs, the contract filesystem.
*
* Exposes the constract subsystem to userland. The structure of the
* filesytem is a public interface, but the behavior of the files is
* private and unstable. Contract consumers are expected to use
* libcontract(3lib) to operate on ctfs file descriptors.
*
* We're trying something a little different here. Rather than make
* each vnode op itself call into a vector of file type operations, we
* actually use different vnode types (gasp!), the implementations of
* which may call into routines providing common functionality. This
* design should hopefully make it easier to factor and maintain the
* code. For the most part, there is a separate file for each vnode
* type's implementation. The exceptions to this are the ctl/stat
* nodes, which are very similar, and the three event endpoint types.
*
* This file contains common routines used by some or all of the vnode
* types, the filesystem's module linkage and VFS operations, and the
* implementation of the root vnode.
*/
/*
* Ops vectors for all the vnode types; they have to be defined
* somewhere. See gfs_make_opsvec for thoughts on how this could be
* done differently.
*/
vnodeops_t *ctfs_ops_root;
vnodeops_t *ctfs_ops_adir;
vnodeops_t *ctfs_ops_sym;
vnodeops_t *ctfs_ops_tdir;
vnodeops_t *ctfs_ops_tmpl;
vnodeops_t *ctfs_ops_cdir;
vnodeops_t *ctfs_ops_ctl;
vnodeops_t *ctfs_ops_stat;
vnodeops_t *ctfs_ops_event;
vnodeops_t *ctfs_ops_bundle;
vnodeops_t *ctfs_ops_latest;
static const fs_operation_def_t ctfs_vfstops[];
static gfs_opsvec_t ctfs_opsvec[];
static int ctfs_init(int, char *);
static ino64_t ctfs_root_do_inode(vnode_t *, int);
/*
* File system module linkage
*/
static mntopts_t ctfs_mntopts = {
0,
NULL
};
static vfsdef_t vfw = {
VFSDEF_VERSION,
"ctfs",
ctfs_init,
VSW_HASPROTO,
&ctfs_mntopts,
};
extern struct mod_ops mod_fsops;
static struct modlfs modlfs = {
&mod_fsops, "contract filesystem", &vfw
};
static struct modlinkage modlinkage = {
MODREV_1, (void *)&modlfs, NULL
};
int
_init(void)
{
return (mod_install(&modlinkage));
}
int
_info(struct modinfo *modinfop)
{
return (mod_info(&modlinkage, modinfop));
}
int
_fini(void)
{
/*
* As unloading filesystem modules isn't completely safe, we
* don't allow it.
*/
return (EBUSY);
}
static int ctfs_fstype;
static major_t ctfs_major;
static minor_t ctfs_minor = 0;
/*
* The ops vector vector.
*/
static const fs_operation_def_t ctfs_tops_root[];
extern const fs_operation_def_t ctfs_tops_tmpl[];
extern const fs_operation_def_t ctfs_tops_ctl[];
extern const fs_operation_def_t ctfs_tops_adir[];
extern const fs_operation_def_t ctfs_tops_cdir[];
extern const fs_operation_def_t ctfs_tops_tdir[];
extern const fs_operation_def_t ctfs_tops_latest[];
extern const fs_operation_def_t ctfs_tops_stat[];
extern const fs_operation_def_t ctfs_tops_sym[];
extern const fs_operation_def_t ctfs_tops_event[];
extern const fs_operation_def_t ctfs_tops_bundle[];
static gfs_opsvec_t ctfs_opsvec[] = {
{ "ctfs root directory", ctfs_tops_root, &ctfs_ops_root },
{ "ctfs all directory", ctfs_tops_adir, &ctfs_ops_adir },
{ "ctfs all symlink", ctfs_tops_sym, &ctfs_ops_sym },
{ "ctfs template directory", ctfs_tops_tdir, &ctfs_ops_tdir },
{ "ctfs template file", ctfs_tops_tmpl, &ctfs_ops_tmpl },
{ "ctfs contract directory", ctfs_tops_cdir, &ctfs_ops_cdir },
{ "ctfs ctl file", ctfs_tops_ctl, &ctfs_ops_ctl },
{ "ctfs status file", ctfs_tops_stat, &ctfs_ops_stat },
{ "ctfs events file", ctfs_tops_event, &ctfs_ops_event },
{ "ctfs bundle file", ctfs_tops_bundle, &ctfs_ops_bundle },
{ "ctfs latest file", ctfs_tops_latest, &ctfs_ops_latest },
{ NULL }
};
/*
* ctfs_init - the vfsdef_t init entry point
*
* Sets the VFS ops, builds all the vnode ops, and allocates a device
* number.
*/
/* ARGSUSED */
static int
ctfs_init(int fstype, char *name)
{
vfsops_t *vfsops;
int error;
ctfs_fstype = fstype;
if (error = vfs_setfsops(fstype, ctfs_vfstops, &vfsops)) {
cmn_err(CE_WARN, "ctfs_init: bad vfs ops template");
return (error);
}
if (error = gfs_make_opsvec(ctfs_opsvec)) {
(void) vfs_freevfsops(vfsops);
return (error);
}
if ((ctfs_major = getudev()) == (major_t)-1) {
cmn_err(CE_WARN, "ctfs_init: can't get unique device number");
ctfs_major = 0;
}
return (0);
}
/*
* ctfs_mount - the VFS_MOUNT entry point
*/
static int
ctfs_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr)
{
ctfs_vfs_t *data;
dev_t dev;
gfs_dirent_t *dirent;
int i;
if (secpolicy_fs_mount(cr, mvp, vfsp) != 0)
return (EPERM);
if (mvp->v_type != VDIR)
return (ENOTDIR);
if ((uap->flags & MS_OVERLAY) == 0 &&
(mvp->v_count > 1 || (mvp->v_flag & VROOT)))
return (EBUSY);
data = kmem_alloc(sizeof (ctfs_vfs_t), KM_SLEEP);
/*
* Initialize vfs fields not initialized by VFS_INIT/domount
*/
vfsp->vfs_bsize = DEV_BSIZE;
vfsp->vfs_fstype = ctfs_fstype;
do
dev = makedevice(ctfs_major,
atomic_add_32_nv(&ctfs_minor, 1) & L_MAXMIN32);
while (vfs_devismounted(dev));
vfs_make_fsid(&vfsp->vfs_fsid, dev, ctfs_fstype);
vfsp->vfs_data = data;
vfsp->vfs_dev = dev;
/*
* Dynamically create gfs_dirent_t array for the root directory.
*/
dirent = kmem_zalloc((ct_ntypes + 2) * sizeof (gfs_dirent_t), KM_SLEEP);
for (i = 0; i < ct_ntypes; i++) {
dirent[i].gfse_name = (char *)ct_types[i]->ct_type_name;
dirent[i].gfse_ctor = ctfs_create_tdirnode;
dirent[i].gfse_flags = GFS_CACHE_VNODE;
}
dirent[i].gfse_name = "all";
dirent[i].gfse_ctor = ctfs_create_adirnode;
dirent[i].gfse_flags = GFS_CACHE_VNODE;
dirent[i+1].gfse_name = NULL;
/*
* Create root vnode
*/
data->ctvfs_root = gfs_root_create(sizeof (ctfs_rootnode_t),
vfsp, ctfs_ops_root, CTFS_INO_ROOT, dirent, ctfs_root_do_inode,
CTFS_NAME_MAX, NULL, NULL);
kmem_free(dirent, (ct_ntypes + 2) * sizeof (gfs_dirent_t));
return (0);
}
/*
* ctfs_unmount - the VFS_UNMOUNT entry point
*/
static int
ctfs_unmount(vfs_t *vfsp, int flag, struct cred *cr)
{
ctfs_vfs_t *data;
if (secpolicy_fs_unmount(cr, vfsp) != 0)
return (EPERM);
/*
* Supporting forced unmounts would be nice to do at some
* point.
*/
if (flag & MS_FORCE)
return (ENOTSUP);
/*
* We should never have a reference count less than 2: one for
* the caller, one for the root vnode.
*/
ASSERT(vfsp->vfs_count >= 2);
/*
* If we have any active vnodes, they will (transitively) have
* holds on the root vnode.
*/
data = vfsp->vfs_data;
if (data->ctvfs_root->v_count > 1)
return (EBUSY);
/*
* Release the last hold on the root vnode. It will, in turn,
* release its hold on us.
*/
VN_RELE(data->ctvfs_root);
/*
* Disappear.
*/
kmem_free(data, sizeof (ctfs_vfs_t));
return (0);
}
/*
* ctfs_root - the VFS_ROOT entry point
*/
static int
ctfs_root(vfs_t *vfsp, vnode_t **vpp)
{
vnode_t *vp;
vp = ((ctfs_vfs_t *)vfsp->vfs_data)->ctvfs_root;
VN_HOLD(vp);
*vpp = vp;
return (0);
}
/*
* ctfs_statvfs - the VFS_STATVFS entry point
*/
static int
ctfs_statvfs(vfs_t *vfsp, statvfs64_t *sp)
{
dev32_t d32;
int total, i;
bzero(sp, sizeof (*sp));
sp->f_bsize = DEV_BSIZE;
sp->f_frsize = DEV_BSIZE;
for (i = 0, total = 0; i < ct_ntypes; i++)
total += contract_type_count(ct_types[i]);
sp->f_files = total;
sp->f_favail = sp->f_ffree = INT_MAX - total;
(void) cmpldev(&d32, vfsp->vfs_dev);
sp->f_fsid = d32;
(void) strlcpy(sp->f_basetype, vfssw[vfsp->vfs_fstype].vsw_name,
sizeof (sp->f_basetype));
sp->f_flag = vf_to_stf(vfsp->vfs_flag);
sp->f_namemax = CTFS_NAME_MAX;
(void) strlcpy(sp->f_fstr, "contract", sizeof (sp->f_fstr));
return (0);
}
static const fs_operation_def_t ctfs_vfstops[] = {
{ VFSNAME_MOUNT, ctfs_mount },
{ VFSNAME_UNMOUNT, ctfs_unmount },
{ VFSNAME_ROOT, ctfs_root },
{ VFSNAME_STATVFS, ctfs_statvfs },
{ NULL, NULL }
};
/*
* ctfs_common_getattr
*
* Implements functionality common to all ctfs VOP_GETATTR entry
* points. It assumes vap->va_size is set.
*/
void
ctfs_common_getattr(vnode_t *vp, vattr_t *vap)
{
vap->va_uid = 0;
vap->va_gid = 0;
vap->va_rdev = 0;
vap->va_blksize = DEV_BSIZE;
vap->va_nblocks = howmany(vap->va_size, vap->va_blksize);
vap->va_seq = 0;
vap->va_fsid = vp->v_vfsp->vfs_dev;
vap->va_nodeid = gfs_file_inode(vp);
}
/*
* ctfs_open - common VOP_OPEN entry point
*
* Used by all ctfs directories; just verifies we are using large-file
* aware interfaces and we aren't trying to open the directories
* writable.
*/
/* ARGSUSED */
int
ctfs_open(vnode_t **vpp, int flag, cred_t *cr)
{
if ((flag & (FOFFMAX | FWRITE)) != FOFFMAX)
return (EINVAL);
return (0);
}
/*
* ctfs_close - common VOP_CLOSE entry point
*
* For all ctfs vnode types which have no close-time clean-up to do.
*/
/* ARGSUSED */
int
ctfs_close(vnode_t *vp, int flag, int count, offset_t offset, cred_t *cr)
{
return (0);
}
/*
* ctfs_access_dir - common VOP_ACCESS entry point for directories
*/
/* ARGSUSED */
int
ctfs_access_dir(vnode_t *vp, int mode, int flags, cred_t *cr)
{
if (mode & VWRITE)
return (EACCES);
return (0);
}
/*
* ctfs_access_dir - common VOP_ACCESS entry point for read-only files
*/
/* ARGSUSED */
int
ctfs_access_readonly(vnode_t *vp, int mode, int flags, cred_t *cr)
{
if (mode & (VWRITE | VEXEC))
return (EACCES);
return (0);
}
/*
* ctfs_access_dir - common VOP_ACCESS entry point for read-write files
*/
/* ARGSUSED */
int
ctfs_access_readwrite(vnode_t *vp, int mode, int flags, cred_t *cr)
{
if (mode & VEXEC)
return (EACCES);
return (0);
}
/*
* ctfs_root_getattr - VOP_GETATTR entry point
*/
/* ARGSUSED */
static int
ctfs_root_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr)
{
vap->va_type = VDIR;
vap->va_mode = 0555;
vap->va_nlink = 2 + ct_ntypes + 1;
vap->va_size = vap->va_nlink;
vap->va_atime.tv_sec = vp->v_vfsp->vfs_mtime;
vap->va_atime.tv_nsec = 0;
vap->va_mtime = vap->va_ctime = vap->va_atime;
ctfs_common_getattr(vp, vap);
return (0);
}
/* ARGSUSED */
static ino64_t
ctfs_root_do_inode(vnode_t *vp, int index)
{
return (CTFS_INO_TYPE_DIR(index));
}
static const fs_operation_def_t ctfs_tops_root[] = {
{ VOPNAME_OPEN, ctfs_open },
{ VOPNAME_CLOSE, ctfs_close },
{ VOPNAME_IOCTL, fs_inval },
{ VOPNAME_GETATTR, ctfs_root_getattr },
{ VOPNAME_ACCESS, ctfs_access_dir },
{ VOPNAME_READDIR, gfs_vop_readdir },
{ VOPNAME_LOOKUP, gfs_vop_lookup },
{ VOPNAME_SEEK, fs_seek },
{ VOPNAME_INACTIVE, (fs_generic_func_p) gfs_vop_inactive },
{ NULL, NULL }
};