freebsd-dev/sys/fs/umapfs/umap_vnops.c
Julian Elischer b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00

520 lines
14 KiB
C

/*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software donated to Berkeley by
* the UCLA Ficus project.
*
* 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 the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* @(#)umap_vnops.c 8.6 (Berkeley) 5/22/95
* $FreeBSD$
*/
/*
* Umap Layer
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <fs/umapfs/umap.h>
#include <fs/nullfs/null.h>
static int umap_bug_bypass = 0; /* for debugging: enables bypass printf'ing */
SYSCTL_INT(_debug, OID_AUTO, umapfs_bug_bypass, CTLFLAG_RW,
&umap_bug_bypass, 0, "");
static int umap_bypass __P((struct vop_generic_args *ap));
static int umap_getattr __P((struct vop_getattr_args *ap));
static int umap_inactive __P((struct vop_inactive_args *ap));
static int umap_lock __P((struct vop_lock_args *ap));
static int umap_print __P((struct vop_print_args *ap));
static int umap_reclaim __P((struct vop_reclaim_args *ap));
static int umap_rename __P((struct vop_rename_args *ap));
static int umap_unlock __P((struct vop_unlock_args *ap));
/*
* This is the 10-Apr-92 bypass routine.
* See null_vnops.c:null_bypass for more details.
*/
static int
umap_bypass(ap)
struct vop_generic_args /* {
struct vnodeop_desc *a_desc;
<other random data follows, presumably>
} */ *ap;
{
struct ucred **credpp = 0, *credp = 0;
struct ucred *savecredp = 0, *savecompcredp = 0;
struct ucred *compcredp = 0;
struct vnode **this_vp_p;
int error;
struct vnode *old_vps[VDESC_MAX_VPS];
struct vnode *vp1 = 0;
struct vnode **vps_p[VDESC_MAX_VPS];
struct vnode ***vppp;
struct vnodeop_desc *descp = ap->a_desc;
int reles, i;
struct componentname **compnamepp = 0;
if (umap_bug_bypass)
printf ("umap_bypass: %s\n", descp->vdesc_name);
#ifdef DIAGNOSTIC
/*
* We require at least one vp.
*/
if (descp->vdesc_vp_offsets == NULL ||
descp->vdesc_vp_offsets[0] == VDESC_NO_OFFSET)
panic ("umap_bypass: no vp's in map");
#endif
/*
* Map the vnodes going in.
* Later, we'll invoke the operation based on
* the first mapped vnode's operation vector.
*/
reles = descp->vdesc_flags;
for (i = 0; i < VDESC_MAX_VPS; reles >>= 1, i++) {
if (descp->vdesc_vp_offsets[i] == VDESC_NO_OFFSET)
break; /* bail out at end of list */
vps_p[i] = this_vp_p =
VOPARG_OFFSETTO(struct vnode**, descp->vdesc_vp_offsets[i], ap);
if (i == 0) {
vp1 = *vps_p[0];
}
/*
* We're not guaranteed that any but the first vnode
* are of our type. Check for and don't map any
* that aren't. (Must map first vp or vclean fails.)
*/
if (i && (*this_vp_p)->v_op != umap_vnodeop_p) {
old_vps[i] = NULL;
} else {
old_vps[i] = *this_vp_p;
*(vps_p[i]) = UMAPVPTOLOWERVP(*this_vp_p);
if (reles & 1)
VREF(*this_vp_p);
}
}
/*
* Fix the credentials. (That's the purpose of this layer.)
*/
if (descp->vdesc_cred_offset != VDESC_NO_OFFSET) {
credpp = VOPARG_OFFSETTO(struct ucred**,
descp->vdesc_cred_offset, ap);
/* Save old values */
savecredp = (*credpp);
if (savecredp != NOCRED)
(*credpp) = crdup(savecredp);
credp = *credpp;
if (umap_bug_bypass && credp->cr_uid != 0)
printf("umap_bypass: user was %lu, group %lu\n",
(u_long)credp->cr_uid, (u_long)credp->cr_gid);
/* Map all ids in the credential structure. */
umap_mapids(vp1->v_mount, credp);
if (umap_bug_bypass && credp->cr_uid != 0)
printf("umap_bypass: user now %lu, group %lu\n",
(u_long)credp->cr_uid, (u_long)credp->cr_gid);
}
/* BSD often keeps a credential in the componentname structure
* for speed. If there is one, it better get mapped, too.
*/
if (descp->vdesc_componentname_offset != VDESC_NO_OFFSET) {
compnamepp = VOPARG_OFFSETTO(struct componentname**,
descp->vdesc_componentname_offset, ap);
compcredp = (*compnamepp)->cn_cred;
savecompcredp = compcredp;
if (savecompcredp != NOCRED)
(*compnamepp)->cn_cred = crdup(savecompcredp);
compcredp = (*compnamepp)->cn_cred;
if (umap_bug_bypass && compcredp->cr_uid != 0)
printf(
"umap_bypass: component credit user was %lu, group %lu\n",
(u_long)compcredp->cr_uid,
(u_long)compcredp->cr_gid);
/* Map all ids in the credential structure. */
umap_mapids(vp1->v_mount, compcredp);
if (umap_bug_bypass && compcredp->cr_uid != 0)
printf(
"umap_bypass: component credit user now %lu, group %lu\n",
(u_long)compcredp->cr_uid,
(u_long)compcredp->cr_gid);
}
/*
* Call the operation on the lower layer
* with the modified argument structure.
*/
error = VCALL(*(vps_p[0]), descp->vdesc_offset, ap);
/*
* Maintain the illusion of call-by-value
* by restoring vnodes in the argument structure
* to their original value.
*/
reles = descp->vdesc_flags;
for (i = 0; i < VDESC_MAX_VPS; reles >>= 1, i++) {
if (descp->vdesc_vp_offsets[i] == VDESC_NO_OFFSET)
break; /* bail out at end of list */
if (old_vps[i]) {
*(vps_p[i]) = old_vps[i];
if (reles & 1)
vrele(*(vps_p[i]));
};
};
/*
* Map the possible out-going vpp
* (Assumes that the lower layer always returns
* a VREF'ed vpp unless it gets an error.)
*/
if (descp->vdesc_vpp_offset != VDESC_NO_OFFSET &&
!(descp->vdesc_flags & VDESC_NOMAP_VPP) &&
!error) {
if (descp->vdesc_flags & VDESC_VPP_WILLRELE)
goto out;
vppp = VOPARG_OFFSETTO(struct vnode***,
descp->vdesc_vpp_offset, ap);
if (*vppp)
error = umap_node_create(old_vps[0]->v_mount, **vppp, *vppp);
};
out:
/*
* Free duplicate cred structure and restore old one.
*/
if (descp->vdesc_cred_offset != VDESC_NO_OFFSET) {
if (umap_bug_bypass && credp && credp->cr_uid != 0)
printf("umap_bypass: returning-user was %lu\n",
(u_long)credp->cr_uid);
if (savecredp != NOCRED) {
crfree(credp);
(*credpp) = savecredp;
if (umap_bug_bypass && credpp && (*credpp)->cr_uid != 0)
printf(
"umap_bypass: returning-user now %lu\n\n",
(u_long)(*credpp)->cr_uid);
}
}
if (descp->vdesc_componentname_offset != VDESC_NO_OFFSET) {
if (umap_bug_bypass && compcredp && compcredp->cr_uid != 0)
printf(
"umap_bypass: returning-component-user was %lu\n",
(u_long)compcredp->cr_uid);
if (savecompcredp != NOCRED) {
crfree(compcredp);
(*compnamepp)->cn_cred = savecompcredp;
if (umap_bug_bypass && credpp && (*credpp)->cr_uid != 0)
printf(
"umap_bypass: returning-component-user now %lu\n",
(u_long)compcredp->cr_uid);
}
}
return (error);
}
/*
* We handle getattr to change the fsid.
*/
static int
umap_getattr(ap)
struct vop_getattr_args /* {
struct vnode *a_vp;
struct vattr *a_vap;
struct ucred *a_cred;
struct thread *a_td;
} */ *ap;
{
short uid, gid;
int error, tmpid, nentries, gnentries;
u_long (*mapdata)[2], (*gmapdata)[2];
struct vnode **vp1p;
struct vnodeop_desc *descp = ap->a_desc;
error = umap_bypass((struct vop_generic_args *)ap);
if (error)
return (error);
/*
* Umap needs to map the uid and gid returned by a stat
* into the proper values for this site. This involves
* finding the returned uid in the mapping information,
* translating it into the uid on the other end,
* and filling in the proper field in the vattr
* structure pointed to by ap->a_vap. The group
* is easier, since currently all groups will be
* translate to the NULLGROUP.
*/
/* Find entry in map */
uid = ap->a_vap->va_uid;
gid = ap->a_vap->va_gid;
if (umap_bug_bypass)
printf("umap_getattr: mapped uid = %d, mapped gid = %d\n", uid,
gid);
vp1p = VOPARG_OFFSETTO(struct vnode**, descp->vdesc_vp_offsets[0], ap);
nentries = MOUNTTOUMAPMOUNT((*vp1p)->v_mount)->info_nentries;
mapdata = (MOUNTTOUMAPMOUNT((*vp1p)->v_mount)->info_mapdata);
gnentries = MOUNTTOUMAPMOUNT((*vp1p)->v_mount)->info_gnentries;
gmapdata = (MOUNTTOUMAPMOUNT((*vp1p)->v_mount)->info_gmapdata);
/* Reverse map the uid for the vnode. Since it's a reverse
map, we can't use umap_mapids() to do it. */
tmpid = umap_reverse_findid(uid, mapdata, nentries);
if (tmpid != -1) {
ap->a_vap->va_uid = (uid_t) tmpid;
if (umap_bug_bypass)
printf("umap_getattr: original uid = %d\n", uid);
} else
ap->a_vap->va_uid = (uid_t) NOBODY;
/* Reverse map the gid for the vnode. */
tmpid = umap_reverse_findid(gid, gmapdata, gnentries);
if (tmpid != -1) {
ap->a_vap->va_gid = (gid_t) tmpid;
if (umap_bug_bypass)
printf("umap_getattr: original gid = %d\n", gid);
} else
ap->a_vap->va_gid = (gid_t) NULLGROUP;
return (0);
}
/*
* We need to process our own vnode lock and then clear the
* interlock flag as it applies only to our vnode, not the
* vnodes below us on the stack.
*/
static int
umap_lock(ap)
struct vop_lock_args /* {
struct vnode *a_vp;
int a_flags;
struct thread *a_td;
} */ *ap;
{
vop_nolock(ap);
if ((ap->a_flags & LK_TYPE_MASK) == LK_DRAIN)
return (0);
ap->a_flags &= ~LK_INTERLOCK;
return (null_bypass((struct vop_generic_args *)ap));
}
/*
* We need to process our own vnode unlock and then clear the
* interlock flag as it applies only to our vnode, not the
* vnodes below us on the stack.
*/
int
umap_unlock(ap)
struct vop_unlock_args /* {
struct vnode *a_vp;
int a_flags;
struct thread *a_td;
} */ *ap;
{
vop_nounlock(ap);
ap->a_flags &= ~LK_INTERLOCK;
return (null_bypass((struct vop_generic_args *)ap));
}
static int
umap_inactive(ap)
struct vop_inactive_args /* {
struct vnode *a_vp;
struct thread *a_td;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct umap_node *xp = VTOUMAP(vp);
struct vnode *lowervp = xp->umap_lowervp;
/*
* Do nothing (and _don't_ bypass).
* Wait to vrele lowervp until reclaim,
* so that until then our umap_node is in the
* cache and reusable.
*
*/
VOP_INACTIVE(lowervp, ap->a_td);
VOP_UNLOCK(ap->a_vp, 0, ap->a_td);
return (0);
}
static int
umap_reclaim(ap)
struct vop_reclaim_args /* {
struct vnode *a_vp;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct umap_node *xp = VTOUMAP(vp);
struct vnode *lowervp = xp->umap_lowervp;
/* After this assignment, this node will not be re-used. */
xp->umap_lowervp = NULL;
LIST_REMOVE(xp, umap_hash);
FREE(vp->v_data, M_TEMP);
vp->v_data = NULL;
vrele(lowervp);
return (0);
}
static int
umap_print(ap)
struct vop_print_args /* {
struct vnode *a_vp;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
printf("\ttag VT_UMAPFS, vp=%p, lowervp=%p\n", vp, UMAPVPTOLOWERVP(vp));
return (0);
}
static int
umap_rename(ap)
struct vop_rename_args /* {
struct vnode *a_fdvp;
struct vnode *a_fvp;
struct componentname *a_fcnp;
struct vnode *a_tdvp;
struct vnode *a_tvp;
struct componentname *a_tcnp;
} */ *ap;
{
int error;
struct componentname *compnamep;
struct ucred *compcredp, *savecompcredp;
struct vnode *vp;
/*
* Rename is irregular, having two componentname structures.
* We need to map the cre in the second structure,
* and then bypass takes care of the rest.
*/
vp = ap->a_fdvp;
compnamep = ap->a_tcnp;
compcredp = compnamep->cn_cred;
savecompcredp = compcredp;
compcredp = compnamep->cn_cred = crdup(savecompcredp);
if (umap_bug_bypass && compcredp->cr_uid != 0)
printf(
"umap_rename: rename component credit user was %lu, group %lu\n",
(u_long)compcredp->cr_uid, (u_long)compcredp->cr_gid);
/* Map all ids in the credential structure. */
umap_mapids(vp->v_mount, compcredp);
if (umap_bug_bypass && compcredp->cr_uid != 0)
printf(
"umap_rename: rename component credit user now %lu, group %lu\n",
(u_long)compcredp->cr_uid, (u_long)compcredp->cr_gid);
error = umap_bypass((struct vop_generic_args *)ap);
/* Restore the additional mapped componentname cred structure. */
crfree(compcredp);
compnamep->cn_cred = savecompcredp;
return error;
}
/*
* Global vfs data structures
*/
/*
* XXX - strategy, bwrite are hand coded currently. They should
* go away with a merged buffer/block cache.
*
*/
vop_t **umap_vnodeop_p;
static struct vnodeopv_entry_desc umap_vnodeop_entries[] = {
{ &vop_default_desc, (vop_t *) umap_bypass },
{ &vop_getattr_desc, (vop_t *) umap_getattr },
{ &vop_inactive_desc, (vop_t *) umap_inactive },
{ &vop_lock_desc, (vop_t *) umap_lock },
{ &vop_print_desc, (vop_t *) umap_print },
{ &vop_reclaim_desc, (vop_t *) umap_reclaim },
{ &vop_rename_desc, (vop_t *) umap_rename },
{ &vop_unlock_desc, (vop_t *) umap_unlock },
{ NULL, NULL }
};
static struct vnodeopv_desc umap_vnodeop_opv_desc =
{ &umap_vnodeop_p, umap_vnodeop_entries };
VNODEOP_SET(umap_vnodeop_opv_desc);