freebsd-nq/sys/fs/fuse/fuse_file.c
Alan Somers 427d205cb5 fusefs: remove superfluous counter_u64_zero
Reported by:	glebius
Sponsored by:	The FreeBSD Foundation
2019-08-06 00:50:25 +00:00

377 lines
10 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2007-2009 Google Inc. and Amit Singh
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Google Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT
* OWNER 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.
*
* Copyright (C) 2005 Csaba Henk.
* All rights reserved.
*
* Copyright (c) 2019 The FreeBSD Foundation
*
* Portions of this software were developed by BFF Storage Systems, LLC under
* sponsorship from the FreeBSD Foundation.
*
* 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 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 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/counter.h>
#include <sys/module.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <sys/queue.h>
#include <sys/lock.h>
#include <sys/sx.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/sdt.h>
#include <sys/sysctl.h>
#include "fuse.h"
#include "fuse_file.h"
#include "fuse_internal.h"
#include "fuse_io.h"
#include "fuse_ipc.h"
#include "fuse_node.h"
MALLOC_DEFINE(M_FUSE_FILEHANDLE, "fuse_filefilehandle", "FUSE file handle");
SDT_PROVIDER_DECLARE(fusefs);
/*
* Fuse trace probe:
* arg0: verbosity. Higher numbers give more verbose messages
* arg1: Textual message
*/
SDT_PROBE_DEFINE2(fusefs, , file, trace, "int", "char*");
static counter_u64_t fuse_fh_count;
SYSCTL_COUNTER_U64(_vfs_fusefs_stats, OID_AUTO, filehandle_count, CTLFLAG_RD,
&fuse_fh_count, "number of open FUSE filehandles");
/* Get the FUFH type for a particular access mode */
static inline fufh_type_t
fflags_2_fufh_type(int fflags)
{
if ((fflags & FREAD) && (fflags & FWRITE))
return FUFH_RDWR;
else if (fflags & (FWRITE))
return FUFH_WRONLY;
else if (fflags & (FREAD))
return FUFH_RDONLY;
else if (fflags & (FEXEC))
return FUFH_EXEC;
else
panic("FUSE: What kind of a flag is this (%x)?", fflags);
}
int
fuse_filehandle_open(struct vnode *vp, int a_mode,
struct fuse_filehandle **fufhp, struct thread *td, struct ucred *cred)
{
struct fuse_dispatcher fdi;
struct fuse_open_in *foi;
struct fuse_open_out *foo;
fufh_type_t fufh_type;
int err = 0;
int oflags = 0;
int op = FUSE_OPEN;
fufh_type = fflags_2_fufh_type(a_mode);
oflags = fufh_type_2_fflags(fufh_type);
if (vnode_isdir(vp)) {
op = FUSE_OPENDIR;
/* vn_open_vnode already rejects FWRITE on directories */
MPASS(fufh_type == FUFH_RDONLY || fufh_type == FUFH_EXEC);
}
fdisp_init(&fdi, sizeof(*foi));
fdisp_make_vp(&fdi, op, vp, td, cred);
foi = fdi.indata;
foi->flags = oflags;
if ((err = fdisp_wait_answ(&fdi))) {
SDT_PROBE2(fusefs, , file, trace, 1,
"OUCH ... daemon didn't give fh");
if (err == ENOENT) {
fuse_internal_vnode_disappear(vp);
}
goto out;
}
foo = fdi.answ;
fuse_filehandle_init(vp, fufh_type, fufhp, td, cred, foo);
fuse_vnode_open(vp, foo->open_flags, td);
out:
fdisp_destroy(&fdi);
return err;
}
int
fuse_filehandle_close(struct vnode *vp, struct fuse_filehandle *fufh,
struct thread *td, struct ucred *cred)
{
struct fuse_dispatcher fdi;
struct fuse_release_in *fri;
int err = 0;
int op = FUSE_RELEASE;
if (fuse_isdeadfs(vp)) {
goto out;
}
if (vnode_isdir(vp))
op = FUSE_RELEASEDIR;
fdisp_init(&fdi, sizeof(*fri));
fdisp_make_vp(&fdi, op, vp, td, cred);
fri = fdi.indata;
fri->fh = fufh->fh_id;
fri->flags = fufh_type_2_fflags(fufh->fufh_type);
/*
* If the file has a POSIX lock then we're supposed to set lock_owner.
* If not, then lock_owner is undefined. So we may as well always set
* it.
*/
fri->lock_owner = td->td_proc->p_pid;
err = fdisp_wait_answ(&fdi);
fdisp_destroy(&fdi);
out:
counter_u64_add(fuse_fh_count, -1);
LIST_REMOVE(fufh, next);
free(fufh, M_FUSE_FILEHANDLE);
return err;
}
/*
* Check for a valid file handle, first the type requested, but if that
* isn't valid, try for FUFH_RDWR.
* Return true if there is any file handle with the correct credentials and
* a fufh type that includes the provided one.
* A pid of 0 means "don't care"
*/
bool
fuse_filehandle_validrw(struct vnode *vp, int mode,
struct ucred *cred, pid_t pid)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
fufh_type_t fufh_type = fflags_2_fufh_type(mode);
/*
* Unlike fuse_filehandle_get, we want to search for a filehandle with
* the exact cred, and no fallback
*/
LIST_FOREACH(fufh, &fvdat->handles, next) {
if (fufh->fufh_type == fufh_type &&
fufh->uid == cred->cr_uid &&
fufh->gid == cred->cr_rgid &&
(pid == 0 || fufh->pid == pid))
return true;
}
if (fufh_type == FUFH_EXEC)
return false;
/* Fallback: find a RDWR list entry with the right cred */
LIST_FOREACH(fufh, &fvdat->handles, next) {
if (fufh->fufh_type == FUFH_RDWR &&
fufh->uid == cred->cr_uid &&
fufh->gid == cred->cr_rgid &&
(pid == 0 || fufh->pid == pid))
return true;
}
return false;
}
int
fuse_filehandle_get(struct vnode *vp, int fflag,
struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
fufh_type_t fufh_type;
fufh_type = fflags_2_fufh_type(fflag);
/* cred can be NULL for in-kernel clients */
if (cred == NULL)
goto fallback;
LIST_FOREACH(fufh, &fvdat->handles, next) {
if (fufh->fufh_type == fufh_type &&
fufh->uid == cred->cr_uid &&
fufh->gid == cred->cr_rgid &&
(pid == 0 || fufh->pid == pid))
goto found;
}
fallback:
/* Fallback: find a list entry with the right flags */
LIST_FOREACH(fufh, &fvdat->handles, next) {
if (fufh->fufh_type == fufh_type)
break;
}
if (fufh == NULL)
return EBADF;
found:
if (fufhp != NULL)
*fufhp = fufh;
return 0;
}
/* Get a file handle with any kind of flags */
int
fuse_filehandle_get_anyflags(struct vnode *vp,
struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
if (cred == NULL)
goto fallback;
LIST_FOREACH(fufh, &fvdat->handles, next) {
if (fufh->uid == cred->cr_uid &&
fufh->gid == cred->cr_rgid &&
(pid == 0 || fufh->pid == pid))
goto found;
}
fallback:
/* Fallback: find any list entry */
fufh = LIST_FIRST(&fvdat->handles);
if (fufh == NULL)
return EBADF;
found:
if (fufhp != NULL)
*fufhp = fufh;
return 0;
}
int
fuse_filehandle_getrw(struct vnode *vp, int fflag,
struct fuse_filehandle **fufhp, struct ucred *cred, pid_t pid)
{
int err;
err = fuse_filehandle_get(vp, fflag, fufhp, cred, pid);
if (err)
err = fuse_filehandle_get(vp, FREAD | FWRITE, fufhp, cred, pid);
return err;
}
void
fuse_filehandle_init(struct vnode *vp, fufh_type_t fufh_type,
struct fuse_filehandle **fufhp, struct thread *td, struct ucred *cred,
struct fuse_open_out *foo)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
fufh = malloc(sizeof(struct fuse_filehandle), M_FUSE_FILEHANDLE,
M_WAITOK);
MPASS(fufh != NULL);
fufh->fh_id = foo->fh;
fufh->fufh_type = fufh_type;
fufh->gid = cred->cr_rgid;
fufh->uid = cred->cr_uid;
fufh->pid = td->td_proc->p_pid;
fufh->fuse_open_flags = foo->open_flags;
if (!FUFH_IS_VALID(fufh)) {
panic("FUSE: init: invalid filehandle id (type=%d)", fufh_type);
}
LIST_INSERT_HEAD(&fvdat->handles, fufh, next);
if (fufhp != NULL)
*fufhp = fufh;
counter_u64_add(fuse_fh_count, 1);
if (foo->open_flags & FOPEN_DIRECT_IO) {
ASSERT_VOP_ELOCKED(vp, __func__);
VTOFUD(vp)->flag |= FN_DIRECTIO;
fuse_io_invalbuf(vp, td);
} else {
if ((foo->open_flags & FOPEN_KEEP_CACHE) == 0)
fuse_io_invalbuf(vp, td);
VTOFUD(vp)->flag &= ~FN_DIRECTIO;
}
}
void
fuse_file_init(void)
{
fuse_fh_count = counter_u64_alloc(M_WAITOK);
}
void
fuse_file_destroy(void)
{
counter_u64_free(fuse_fh_count);
}