diff options
Diffstat (limited to 'sys/miscfs/umapfs/umap_vnops.c')
-rw-r--r-- | sys/miscfs/umapfs/umap_vnops.c | 488 |
1 files changed, 488 insertions, 0 deletions
diff --git a/sys/miscfs/umapfs/umap_vnops.c b/sys/miscfs/umapfs/umap_vnops.c new file mode 100644 index 0000000..287804e --- /dev/null +++ b/sys/miscfs/umapfs/umap_vnops.c @@ -0,0 +1,488 @@ +/* + * 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 8.3 (Berkeley) 1/5/94 + */ + +/* + * Umap Layer + */ + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/vnode.h> +#include <sys/mount.h> +#include <sys/namei.h> +#include <sys/malloc.h> +#include <sys/buf.h> +#include <miscfs/umapfs/umap.h> + + +int umap_bug_bypass = 0; /* for debugging: enables bypass printf'ing */ + +/* + * This is the 10-Apr-92 bypass routine. + * See null_vnops.c:null_bypass for more details. + */ +int +umap_bypass(ap) + struct vop_generic_args /* { + struct vnodeop_desc *a_desc; + <other random data follows, presumably> + } */ *ap; +{ + extern int (**umap_vnodeop_p)(); /* not extern, really "forward" */ + struct ucred **credpp = 0, *credp = 0; + struct ucred *savecredp, *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 SAFETY + /* + * 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.\n"); +#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); + (*credpp) = crdup(savecredp); + credp = *credpp; + + if (umap_bug_bypass && credp->cr_uid != 0) + printf("umap_bypass: user was %d, group %d\n", + credp->cr_uid, 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 %d, group %d\n", + credp->cr_uid, 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; + compcredp = (*compnamepp)->cn_cred = crdup(savecompcredp); + + if (umap_bug_bypass && compcredp->cr_uid != 0) + printf("umap_bypass: component credit user was %d, group %d\n", + compcredp->cr_uid, 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 %d, group %d\n", + compcredp->cr_uid, 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); + 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 %d\n", + credp->cr_uid); + + crfree(credp); + (*credpp) = savecredp; + if (umap_bug_bypass && credpp && (*credpp)->cr_uid != 0) + printf("umap_bypass: returning-user now %d\n\n", + (*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 %d\n", + compcredp->cr_uid); + + crfree(compcredp); + (*compnamepp)->cn_cred = savecompcredp; + if (umap_bug_bypass && credpp && (*credpp)->cr_uid != 0) + printf("umap_bypass: returning-component-user now %d\n", + compcredp->cr_uid); + } + + return (error); +} + + +/* + * We handle getattr to change the fsid. + */ +int +umap_getattr(ap) + struct vop_getattr_args /* { + struct vnode *a_vp; + struct vattr *a_vap; + struct ucred *a_cred; + struct proc *a_p; + } */ *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; + + if (error = umap_bypass(ap)) + return (error); + /* Requires that arguments be restored. */ + ap->a_vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; + + /* + * 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); +} + +int +umap_inactive(ap) + struct vop_inactive_args /* { + struct vnode *a_vp; + } */ *ap; +{ + /* + * 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. + * + */ + return (0); +} + +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; + remque(xp); + FREE(vp->v_data, M_TEMP); + vp->v_data = NULL; + vrele(lowervp); + return (0); +} + +int +umap_strategy(ap) + struct vop_strategy_args /* { + struct buf *a_bp; + } */ *ap; +{ + struct buf *bp = ap->a_bp; + int error; + struct vnode *savedvp; + + savedvp = bp->b_vp; + bp->b_vp = UMAPVPTOLOWERVP(bp->b_vp); + + error = VOP_STRATEGY(ap->a_bp); + + bp->b_vp = savedvp; + + return (error); +} + +int +umap_bwrite(ap) + struct vop_bwrite_args /* { + struct buf *a_bp; + } */ *ap; +{ + struct buf *bp = ap->a_bp; + int error; + struct vnode *savedvp; + + savedvp = bp->b_vp; + bp->b_vp = UMAPVPTOLOWERVP(bp->b_vp); + + error = VOP_BWRITE(ap->a_bp); + + bp->b_vp = savedvp; + + return (error); +} + + +int +umap_print(ap) + struct vop_print_args /* { + struct vnode *a_vp; + } */ *ap; +{ + struct vnode *vp = ap->a_vp; + printf("\ttag VT_UMAPFS, vp=%x, lowervp=%x\n", vp, UMAPVPTOLOWERVP(vp)); + return (0); +} + +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 %d, group %d\n", + compcredp->cr_uid, 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 %d, group %d\n", + compcredp->cr_uid, compcredp->cr_gid); + + error = umap_bypass(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. + * + */ +int (**umap_vnodeop_p)(); +struct vnodeopv_entry_desc umap_vnodeop_entries[] = { + { &vop_default_desc, umap_bypass }, + + { &vop_getattr_desc, umap_getattr }, + { &vop_inactive_desc, umap_inactive }, + { &vop_reclaim_desc, umap_reclaim }, + { &vop_print_desc, umap_print }, + { &vop_rename_desc, umap_rename }, + + { &vop_strategy_desc, umap_strategy }, + { &vop_bwrite_desc, umap_bwrite }, + + { (struct vnodeop_desc*) NULL, (int(*)()) NULL } +}; +struct vnodeopv_desc umap_vnodeop_opv_desc = + { &umap_vnodeop_p, umap_vnodeop_entries }; |