NetBSD/lib/libperfuse/subr.c
manu 075ba0e590 - Fix same vnodes associated with multiple cookies
The scheme used to retreive known nodes on lookup was flawed, as it only
used parent and name. This produced a different cookie for the same file
if it was renamed, when looking up ../ or when dealing with multiple files
associated with the same name through link(2).

We therefore abandon the use of node name and introduce hashed lists of
inodes. This causes a huge rewrite of reclaim code, which do not attempt
to keep parents allocated until all their children are reclaimed

- Fix race conditions in reclaim
There are a few situations where we issue multiple FUSE operations for
a PUFFS operation. On reclaim, we therefore have to wait for all FUSE
operation to complete, not just the current exchanges. We do this by
introducing node reference count with node_ref() and node_rele().

- Detect data loss caused by FAF
VOP_PUTPAGES causes FAF writes where the kernel does not check the
operation result. At least issue a warning on error.

- Enjoy FAF shortcut on setattr
No need to wait for the result if the kernel does not want it. There is
however an exception for setattr that touch the size, we need to wait
for completion because we have other operations queued for after the
resize.

- Fix fchmod() on write-open file
fchmod() on a node open with write privilege will send setattr with both mode and size set. This confuses some FUSE filesystem. Therefore we send two FUSE operations, one for mode, and one for size.

- Remove node TTL handling for netbsd-5 for simplicity sake. The code
still builds on netbsd-5 but does not have the node TTL feature anymore.
It works fine with kernel support on netbsd-6.
2012-07-21 05:49:42 +00:00

318 lines
8.0 KiB
C

/* $NetBSD: subr.c,v 1.19 2012/07/21 05:49:42 manu Exp $ */
/*-
* Copyright (c) 2010-2011 Emmanuel Dreyfus. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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 <stdio.h>
#include <stdlib.h>
#include <err.h>
#include <errno.h>
#include <sysexits.h>
#include <syslog.h>
#include <puffs.h>
#include <paths.h>
#include <sys/hash.h>
#include <sys/extattr.h>
#include "perfuse_priv.h"
struct perfuse_ns_map {
const char *pnm_ns;
const size_t pnm_nslen;
const int pnm_native_ns;
};
#define PERFUSE_NS_MAP(ns, native_ns) \
{ ns ".", sizeof(ns), native_ns }
static __inline struct perfuse_node_hashlist *perfuse_nidhash(struct
perfuse_state *, uint64_t);
struct puffs_node *
perfuse_new_pn(struct puffs_usermount *pu, const char *name,
struct puffs_node *parent)
{
struct perfuse_state *ps = puffs_getspecific(pu);
struct puffs_node *pn;
struct perfuse_node_data *pnd;
if ((pnd = malloc(sizeof(*pnd))) == NULL)
DERR(EX_OSERR, "%s: malloc failed", __func__);
if ((pn = puffs_pn_new(pu, pnd)) == NULL)
DERR(EX_SOFTWARE, "%s: puffs_pn_new failed", __func__);
(void)memset(pnd, 0, sizeof(*pnd));
pnd->pnd_rfh = FUSE_UNKNOWN_FH;
pnd->pnd_wfh = FUSE_UNKNOWN_FH;
pnd->pnd_nodeid = PERFUSE_UNKNOWN_NODEID;
if (parent != NULL) {
pnd->pnd_parent_nodeid = PERFUSE_NODE_DATA(parent)->pnd_nodeid;
} else {
pnd->pnd_parent_nodeid = FUSE_ROOT_ID;
}
pnd->pnd_fuse_nlookup = 0;
pnd->pnd_puffs_nlookup = 0;
pnd->pnd_pn = (puffs_cookie_t)pn;
if (strcmp(name, "..") != 0)
(void)strlcpy(pnd->pnd_name, name, MAXPATHLEN);
else
pnd->pnd_name[0] = 0; /* anonymous for now */
TAILQ_INIT(&pnd->pnd_pcq);
puffs_pn_setpriv(pn, pnd);
ps->ps_nodecount++;
return pn;
}
void
perfuse_destroy_pn(struct puffs_usermount *pu, struct puffs_node *pn)
{
struct perfuse_state *ps = puffs_getspecific(pu);
struct perfuse_node_data *pnd;
if ((pnd = puffs_pn_getpriv(pn)) != NULL) {
if (pnd->pnd_all_fd != NULL)
free(pnd->pnd_all_fd);
if (pnd->pnd_dirent != NULL)
free(pnd->pnd_dirent);
#ifdef PERFUSE_DEBUG
if (pnd->pnd_flags & PND_OPEN)
DERRX(EX_SOFTWARE, "%s: file open", __func__);
if (!TAILQ_EMPTY(&pnd->pnd_pcq))
DERRX(EX_SOFTWARE, "%s: non empty pnd_pcq", __func__);
pnd->pnd_flags |= PND_INVALID;
#endif /* PERFUSE_DEBUG */
free(pnd);
}
puffs_pn_put(pn);
ps->ps_nodecount--;
return;
}
void
perfuse_new_fh(puffs_cookie_t opc, uint64_t fh, int mode)
{
struct perfuse_node_data *pnd;
pnd = PERFUSE_NODE_DATA(opc);
if (mode & FWRITE) {
if (pnd->pnd_flags & PND_WFH)
DERRX(EX_SOFTWARE, "%s: opc = %p, write fh already set",
__func__, (void *)opc);
pnd->pnd_wfh = fh;
pnd->pnd_flags |= PND_WFH;
}
if (mode & FREAD) {
if (pnd->pnd_flags & PND_RFH)
DERRX(EX_SOFTWARE, "%s: opc = %p, read fh already set",
__func__, (void *)opc);
pnd->pnd_rfh = fh;
pnd->pnd_flags |= PND_RFH;
}
return;
}
void
perfuse_destroy_fh(puffs_cookie_t opc, uint64_t fh)
{
struct perfuse_node_data *pnd;
pnd = PERFUSE_NODE_DATA(opc);
if (fh == pnd->pnd_rfh) {
if (!(pnd->pnd_flags & PND_RFH) && (fh != FUSE_UNKNOWN_FH))
DERRX(EX_SOFTWARE,
"%s: opc = %p, unset rfh = %"PRIx64"",
__func__, (void *)opc, fh);
pnd->pnd_rfh = FUSE_UNKNOWN_FH;
pnd->pnd_flags &= ~PND_RFH;
}
if (fh == pnd->pnd_wfh) {
if (!(pnd->pnd_flags & PND_WFH) && (fh != FUSE_UNKNOWN_FH))
DERRX(EX_SOFTWARE,
"%s: opc = %p, unset wfh = %"PRIx64"",
__func__, (void *)opc, fh);
pnd->pnd_wfh = FUSE_UNKNOWN_FH;
pnd->pnd_flags &= ~PND_WFH;
}
return;
}
uint64_t
perfuse_get_fh(puffs_cookie_t opc, int mode)
{
struct perfuse_node_data *pnd;
pnd = PERFUSE_NODE_DATA(opc);
if (mode & FWRITE) {
if (pnd->pnd_flags & PND_WFH)
return pnd->pnd_wfh;
}
if (mode & FREAD) {
if (pnd->pnd_flags & PND_RFH)
return pnd->pnd_rfh;
if (pnd->pnd_flags & PND_WFH)
return pnd->pnd_wfh;
}
return FUSE_UNKNOWN_FH;
}
/* ARGSUSED0 */
char *
perfuse_node_path(struct perfuse_state *ps, puffs_cookie_t opc)
{
static char buf[MAXPATHLEN + 1];
#if 0
if (node_path(ps, opc, buf, sizeof(buf)) == 0)
sprintf(buf, "/");
#endif
sprintf(buf, "%s", PERFUSE_NODE_DATA(opc)->pnd_name);
return buf;
}
const char *
perfuse_native_ns(const int attrnamespace, const char *attrname,
char *fuse_attrname)
{
const struct perfuse_ns_map *pnm;
const struct perfuse_ns_map perfuse_ns_map[] = {
PERFUSE_NS_MAP("trusted", EXTATTR_NAMESPACE_SYSTEM),
PERFUSE_NS_MAP("security", EXTATTR_NAMESPACE_SYSTEM),
PERFUSE_NS_MAP("system", EXTATTR_NAMESPACE_SYSTEM),
PERFUSE_NS_MAP("user", EXTATTR_NAMESPACE_USER),
{ NULL, 0, EXTATTR_NAMESPACE_USER },
};
/*
* If attribute has a reserved Linux namespace (e.g.: trusted.foo)
* and that namespace matches the requested native namespace
* we have nothing to do.
* Otherwise we have either:
* (system|trusted|security).* with user namespace: prepend user.
* anything else with system napespace: prepend system.
*/
for (pnm = perfuse_ns_map; pnm->pnm_ns; pnm++) {
if (strncmp(attrname, pnm->pnm_ns, pnm->pnm_nslen) != 0)
continue;
if (attrnamespace == pnm->pnm_native_ns)
return attrname;
/* (system|trusted|security).* with user namespace */
if (attrnamespace == EXTATTR_NAMESPACE_USER) {
(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
"user.%s", attrname);
return (const char *)fuse_attrname;
}
}
/* anything else with system napespace */
if (attrnamespace == EXTATTR_NAMESPACE_SYSTEM) {
(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
"system.%s", attrname);
return (const char *)fuse_attrname;
}
return (const char *)attrname;
}
static __inline struct perfuse_node_hashlist *
perfuse_nidhash(struct perfuse_state *ps, uint64_t nodeid)
{
uint32_t hash;
hash = hash32_buf(&nodeid, sizeof(nodeid), HASH32_BUF_INIT);
return &ps->ps_nidhash[hash % ps->ps_nnidhash];
}
struct perfuse_node_data *
perfuse_node_bynodeid(struct perfuse_state *ps, uint64_t nodeid)
{
struct perfuse_node_hashlist *plist;
struct perfuse_node_data *pnd;
plist = perfuse_nidhash(ps, nodeid);
LIST_FOREACH(pnd, plist, pnd_nident)
if (pnd->pnd_nodeid == nodeid)
break;
return pnd;
}
void
perfuse_node_cache(struct perfuse_state *ps, puffs_cookie_t opc)
{
struct perfuse_node_data *pnd = PERFUSE_NODE_DATA(opc);
struct perfuse_node_hashlist *nidlist;
if (pnd->pnd_flags & PND_REMOVED)
DERRX(EX_SOFTWARE, "%s: \"%s\" already removed",
__func__, pnd->pnd_name);
nidlist = perfuse_nidhash(ps, pnd->pnd_nodeid);
LIST_INSERT_HEAD(nidlist, pnd, pnd_nident);
return;
}
void
perfuse_cache_flush(puffs_cookie_t opc)
{
struct perfuse_node_data *pnd = PERFUSE_NODE_DATA(opc);
if (pnd->pnd_flags & PND_REMOVED)
DERRX(EX_SOFTWARE, "%s: \"%s\" already removed",
__func__, pnd->pnd_name);
LIST_REMOVE(pnd, pnd_nident);
return;
}