freebsd-skq/sys/fs/nwfs/nwfs_node.c
Kirk McKusick a5b65058d5 Regularize the vop_stdlock'ing protocol across all the filesystems
that use it. Specifically, vop_stdlock uses the lock pointed to by
vp->v_vnlock. By default, getnewvnode sets up vp->v_vnlock to
reference vp->v_lock. Filesystems that wish to use the default
do not need to allocate a lock at the front of their node structure
(as some still did) or do a lockinit. They can simply start using
vn_lock/VOP_UNLOCK. Filesystems that wish to manage their own locks,
but still use the vop_stdlock functions (such as nullfs) can simply
replace vp->v_vnlock with a pointer to the lock that they wish to
have used for the vnode. Such filesystems are responsible for
setting the vp->v_vnlock back to the default in their vop_reclaim
routine (e.g., vp->v_vnlock = &vp->v_lock).

In theory, this set of changes cleans up the existing filesystem
lock interface and should have no function change to the existing
locking scheme.

Sponsored by:	DARPA & NAI Labs.
2002-10-14 03:20:36 +00:00

377 lines
10 KiB
C

/*
* Copyright (c) 1999, 2000 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.
*
* $FreeBSD$
*/
#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/mutex.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/vnode.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <vm/vm_page.h>
#include <vm/vm_object.h>
#include <netncp/ncp.h>
#include <netncp/ncp_conn.h>
#include <netncp/ncp_subr.h>
#include <fs/nwfs/nwfs.h>
#include <fs/nwfs/nwfs_mount.h>
#include <fs/nwfs/nwfs_node.h>
#include <fs/nwfs/nwfs_subr.h>
#define NWNOHASH(fhsum) (&nwhashtbl[(fhsum.f_id) & nwnodehash])
extern vop_t **nwfs_vnodeop_p;
static LIST_HEAD(nwnode_hash_head,nwnode) *nwhashtbl;
static u_long nwnodehash;
static struct lock nwhashlock;
MALLOC_DEFINE(M_NWNODE, "NWFS node", "NWFS vnode private part");
MALLOC_DEFINE(M_NWFSHASH, "NWFS hash", "NWFS has table");
static int nwfs_sysctl_vnprint(SYSCTL_HANDLER_ARGS);
SYSCTL_DECL(_vfs_nwfs);
SYSCTL_PROC(_vfs_nwfs, OID_AUTO, vnprint, CTLFLAG_WR|CTLTYPE_OPAQUE,
NULL, 0, nwfs_sysctl_vnprint, "S,vnlist", "vnode hash");
void
nwfs_hash_init(void) {
nwhashtbl = hashinit(desiredvnodes, M_NWFSHASH, &nwnodehash);
lockinit(&nwhashlock, PVFS, "nwfshl", 0, 0);
}
void
nwfs_hash_free(void) {
lockdestroy(&nwhashlock);
free(nwhashtbl, M_NWFSHASH);
}
int
nwfs_sysctl_vnprint(SYSCTL_HANDLER_ARGS) {
struct nwnode *np;
struct nwnode_hash_head *nhpp;
struct vnode *vp;
int i;
if (nwfs_debuglevel == 0)
return 0;
printf("Name:uc:hc:fid:pfid\n");
for(i = 0; i <= nwnodehash; i++) {
nhpp = &nwhashtbl[i];
LIST_FOREACH(np, nhpp, n_hash) {
vp = NWTOV(np);
vprint(NULL, vp);
printf("%s:%d:%d:%d:%d\n",np->n_name,vrefcnt(vp),
vp->v_holdcnt,np->n_fid.f_id, np->n_fid.f_parent);
}
}
return 0;
}
/*
* Search nwnode with given fid.
* Hash list should be locked by caller.
*/
static int
nwfs_hashlookup(struct nwmount *nmp, ncpfid fid, struct nwnode **npp)
{
struct nwnode *np;
struct nwnode_hash_head *nhpp;
nhpp = NWNOHASH(fid);
LIST_FOREACH(np, nhpp, n_hash) {
if (nmp != np->n_mount || !NWCMPF(&fid, &np->n_fid))
continue;
if (npp)
*npp = np;
return 0;
}
return ENOENT;
}
/*
* Allocate new nwfsnode/vnode from given nwnode.
* Vnode referenced and not locked.
*/
static int
nwfs_allocvp(struct mount *mp, ncpfid fid, struct nw_entry_info *fap,
struct vnode *dvp, struct vnode **vpp)
{
struct thread *td = curthread; /* XXX */
struct nwnode *np;
struct nwnode_hash_head *nhpp;
struct nwmount *nmp = VFSTONWFS(mp);
struct vnode *vp;
int error;
loop:
lockmgr(&nwhashlock, LK_EXCLUSIVE, NULL, td);
rescan:
if (nwfs_hashlookup(nmp, fid, &np) == 0) {
vp = NWTOV(np);
mtx_lock(&vp->v_interlock);
lockmgr(&nwhashlock, LK_RELEASE, NULL, td);
if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td))
goto loop;
if (fap)
np->n_attr = fap->attributes;
*vpp = vp;
return(0);
}
lockmgr(&nwhashlock, LK_RELEASE, NULL, td);
if (fap == NULL || ((fap->attributes & aDIR) == 0 && dvp == NULL))
panic("nwfs_allocvp: fap = %p, dvp = %p\n", fap, dvp);
/*
* Do the MALLOC before the getnewvnode since doing so afterward
* might cause a bogus v_data pointer to get dereferenced
* elsewhere if MALLOC should block.
*/
MALLOC(np, struct nwnode *, sizeof *np, M_NWNODE, M_WAITOK | M_ZERO);
error = getnewvnode("nwfs", mp, nwfs_vnodeop_p, &vp);
if (error) {
*vpp = NULL;
FREE(np, M_NWNODE);
return (error);
}
vp->v_data = np;
np->n_vnode = vp;
np->n_mount = nmp;
np->n_attr = fap->attributes;
vp->v_type = np->n_attr & aDIR ? VDIR : VREG;
np->n_fid = fid;
if (dvp) {
np->n_parent = VTONW(dvp)->n_fid;
}
vp->v_vnlock->lk_flags |= LK_CANRECURSE;
lockmgr(&nwhashlock, LK_EXCLUSIVE, NULL, td);
/*
* Another process can create vnode while we blocked in malloc() or
* getnewvnode(). Rescan list again.
*/
if (nwfs_hashlookup(nmp, fid, NULL) == 0) {
vp->v_data = NULL;
np->n_vnode = NULL;
vrele(vp);
FREE(np, M_NWNODE);
goto rescan;
}
*vpp = vp;
nhpp = NWNOHASH(fid);
LIST_INSERT_HEAD(nhpp, np, n_hash);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
lockmgr(&nwhashlock, LK_RELEASE, NULL, td);
ASSERT_VOP_LOCKED(dvp, "nwfs_allocvp");
if (vp->v_type == VDIR && dvp && (dvp->v_vflag & VV_ROOT) == 0) {
np->n_flag |= NREFPARENT;
vref(dvp);
}
return 0;
}
int
nwfs_nget(struct mount *mp, ncpfid fid, struct nw_entry_info *fap,
struct vnode *dvp, struct vnode **vpp)
{
struct vnode *vp;
int error;
*vpp = NULL;
error = nwfs_allocvp(mp, fid, fap, dvp, &vp);
if (error)
return error;
if (fap)
nwfs_attr_cacheenter(vp, fap);
*vpp = vp;
return 0;
}
int
nwfs_lookupnp(struct nwmount *nmp, ncpfid fid, struct thread *td,
struct nwnode **npp)
{
int error;
lockmgr(&nwhashlock, LK_EXCLUSIVE, NULL, td);
error = nwfs_hashlookup(nmp, fid, npp);
lockmgr(&nwhashlock, LK_RELEASE, NULL, td);
return error;
}
/*
* Free nwnode, and give vnode back to system
*/
int
nwfs_reclaim(ap)
struct vop_reclaim_args /* {
struct vnode *a_vp;
struct thread *a_td;
} */ *ap;
{
struct vnode *dvp = NULL, *vp = ap->a_vp;
struct nwnode *dnp, *np = VTONW(vp);
struct nwmount *nmp = VTONWFS(vp);
struct thread *td = ap->a_td;
NCPVNDEBUG("%s,%d\n", np->n_name, vrefcnt(vp));
if (np->n_flag & NREFPARENT) {
np->n_flag &= ~NREFPARENT;
if (nwfs_lookupnp(nmp, np->n_parent, td, &dnp) == 0) {
dvp = dnp->n_vnode;
} else {
NCPVNDEBUG("%s: has no parent ?\n",np->n_name);
}
}
lockmgr(&nwhashlock, LK_EXCLUSIVE, NULL, td);
LIST_REMOVE(np, n_hash);
lockmgr(&nwhashlock, LK_RELEASE, NULL, td);
cache_purge(vp);
if (nmp->n_root == np) {
nmp->n_root = NULL;
}
vp->v_data = NULL;
FREE(np, M_NWNODE);
if (dvp) {
vrele(dvp);
}
return (0);
}
int
nwfs_inactive(ap)
struct vop_inactive_args /* {
struct vnode *a_vp;
struct thread *a_td;
} */ *ap;
{
struct thread *td = ap->a_td;
struct ucred *cred = td->td_ucred;
struct vnode *vp = ap->a_vp;
struct nwnode *np = VTONW(vp);
int error;
NCPVNDEBUG("%s: %d\n", VTONW(vp)->n_name, vrefcnt(vp));
if (np->opened) {
error = nwfs_vinvalbuf(vp, V_SAVE, cred, td, 1);
error = ncp_close_file(NWFSTOCONN(VTONWFS(vp)), &np->n_fh, td, cred);
np->opened = 0;
}
VOP_UNLOCK(vp, 0, td);
if (np->n_flag & NSHOULDFREE) {
cache_purge(vp);
vgone(vp);
}
return (0);
}
/*
* routines to maintain vnode attributes cache
* nwfs_attr_cacheenter: unpack np.i to va structure
*/
void
nwfs_attr_cacheenter(struct vnode *vp, struct nw_entry_info *fi)
{
struct nwnode *np = VTONW(vp);
struct nwmount *nmp = VTONWFS(vp);
struct vattr *va = &np->n_vattr;
va->va_type = vp->v_type; /* vnode type (for create) */
np->n_nmlen = fi->nameLen;
bcopy(fi->entryName, np->n_name, np->n_nmlen);
np->n_name[fi->nameLen] = 0;
if (vp->v_type == VREG) {
if (va->va_size != fi->dataStreamSize) {
va->va_size = fi->dataStreamSize;
vnode_pager_setsize(vp, va->va_size);
}
va->va_mode = nmp->m.file_mode; /* files access mode and type */
} else if (vp->v_type == VDIR) {
va->va_size = 16384; /* should be a better way ... */
va->va_mode = nmp->m.dir_mode; /* files access mode and type */
} else
return;
np->n_size = va->va_size;
va->va_nlink = 1; /* number of references to file */
va->va_uid = nmp->m.uid; /* owner user id */
va->va_gid = nmp->m.gid; /* owner group id */
va->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
va->va_fileid = np->n_fid.f_id; /* file id */
if (va->va_fileid == 0)
va->va_fileid = NWFS_ROOT_INO;
va->va_blocksize=nmp->connh->nh_conn->buffer_size;/* blocksize preferred for i/o */
/* time of last modification */
ncp_dos2unixtime(fi->modifyDate, fi->modifyTime, 0, nmp->m.tz, &va->va_mtime);
/* time of last access */
ncp_dos2unixtime(fi->lastAccessDate, 0, 0, nmp->m.tz, &va->va_atime);
va->va_ctime = va->va_mtime; /* time file changed */
va->va_gen = VNOVAL; /* generation number of file */
va->va_flags = 0; /* flags defined for file */
va->va_rdev = VNOVAL; /* device the special file represents */
va->va_bytes = va->va_size; /* bytes of disk space held by file */
va->va_filerev = 0; /* file modification number */
va->va_vaflags = 0; /* operations flags */
np->n_vattr = *va;
if (np->n_mtime == 0) {
np->n_mtime = va->va_mtime.tv_sec;
}
np->n_atime = time_second;
np->n_dosfid = fi->DosDirNum;
return;
}
int
nwfs_attr_cachelookup(struct vnode *vp, struct vattr *va)
{
struct nwnode *np = VTONW(vp);
int diff;
diff = time_second - np->n_atime;
if (diff > 2) { /* XXX should be configurable */
return ENOENT;
}
*va = np->n_vattr;
return 0;
}