freebsd-skq/sys/fs/fuse/fuse_file.c
2018-08-08 04:46:03 +00:00

289 lines
8.2 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.
*
* 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/types.h>
#include <sys/module.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/param.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/sysctl.h>
#include "fuse.h"
#include "fuse_file.h"
#include "fuse_internal.h"
#include "fuse_ipc.h"
#include "fuse_node.h"
#define FUSE_DEBUG_MODULE FILE
#include "fuse_debug.h"
static int fuse_fh_count = 0;
SYSCTL_INT(_vfs_fuse, OID_AUTO, filehandle_count, CTLFLAG_RD,
&fuse_fh_count, 0, "");
int
fuse_filehandle_open(struct vnode *vp,
fufh_type_t fufh_type,
struct fuse_filehandle **fufhp,
struct thread *td,
struct ucred *cred)
{
struct fuse_dispatcher fdi;
struct fuse_open_in *foi;
struct fuse_open_out *foo;
int err = 0;
int oflags = 0;
int op = FUSE_OPEN;
fuse_trace_printf("fuse_filehandle_open(vp=%p, fufh_type=%d)\n",
vp, fufh_type);
if (fuse_filehandle_valid(vp, fufh_type)) {
panic("FUSE: filehandle_open called despite valid fufh (type=%d)",
fufh_type);
/* NOTREACHED */
}
/*
* Note that this means we are effectively FILTERING OUT open() flags.
*/
oflags = fuse_filehandle_xlate_to_oflags(fufh_type);
if (vnode_isdir(vp)) {
op = FUSE_OPENDIR;
if (fufh_type != FUFH_RDONLY) {
printf("FUSE:non-rdonly fh requested for a directory?\n");
fufh_type = FUFH_RDONLY;
}
}
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))) {
debug_printf("OUCH ... daemon didn't give fh (err = %d)\n", err);
if (err == ENOENT) {
fuse_internal_vnode_disappear(vp);
}
goto out;
}
foo = fdi.answ;
fuse_filehandle_init(vp, fufh_type, fufhp, foo->fh);
/*
* For WRONLY opens, force DIRECT_IO. This is necessary
* since writing a partial block through the buffer cache
* will result in a read of the block and that read won't
* be allowed by the WRONLY open.
*/
if (fufh_type == FUFH_WRONLY)
fuse_vnode_open(vp, foo->open_flags | FOPEN_DIRECT_IO, td);
else
fuse_vnode_open(vp, foo->open_flags, td);
out:
fdisp_destroy(&fdi);
return err;
}
int
fuse_filehandle_close(struct vnode *vp,
fufh_type_t fufh_type,
struct thread *td,
struct ucred *cred)
{
struct fuse_dispatcher fdi;
struct fuse_release_in *fri;
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh = NULL;
int err = 0;
int op = FUSE_RELEASE;
fuse_trace_printf("fuse_filehandle_put(vp=%p, fufh_type=%d)\n",
vp, fufh_type);
fufh = &(fvdat->fufh[fufh_type]);
if (!FUFH_IS_VALID(fufh)) {
panic("FUSE: filehandle_put called on invalid fufh (type=%d)",
fufh_type);
/* NOTREACHED */
}
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 = fuse_filehandle_xlate_to_oflags(fufh_type);
err = fdisp_wait_answ(&fdi);
fdisp_destroy(&fdi);
out:
atomic_subtract_acq_int(&fuse_fh_count, 1);
fufh->fh_id = (uint64_t)-1;
fufh->fh_type = FUFH_INVALID;
return err;
}
int
fuse_filehandle_valid(struct vnode *vp, fufh_type_t fufh_type)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
fufh = &(fvdat->fufh[fufh_type]);
return FUFH_IS_VALID(fufh);
}
/*
* Check for a valid file handle, first the type requested, but if that
* isn't valid, try for FUFH_RDWR.
* Return the FUFH type that is valid or FUFH_INVALID if there are none.
* This is a variant of fuse_filehandle_vaild() analogous to
* fuse_filehandle_getrw().
*/
fufh_type_t
fuse_filehandle_validrw(struct vnode *vp, fufh_type_t fufh_type)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
fufh = &fvdat->fufh[fufh_type];
if (FUFH_IS_VALID(fufh) != 0)
return (fufh_type);
fufh = &fvdat->fufh[FUFH_RDWR];
if (FUFH_IS_VALID(fufh) != 0)
return (FUFH_RDWR);
return (FUFH_INVALID);
}
int
fuse_filehandle_get(struct vnode *vp, fufh_type_t fufh_type,
struct fuse_filehandle **fufhp)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
fufh = &(fvdat->fufh[fufh_type]);
if (!FUFH_IS_VALID(fufh))
return EBADF;
if (fufhp != NULL)
*fufhp = fufh;
return 0;
}
int
fuse_filehandle_getrw(struct vnode *vp, fufh_type_t fufh_type,
struct fuse_filehandle **fufhp)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
fufh = &(fvdat->fufh[fufh_type]);
if (!FUFH_IS_VALID(fufh)) {
fufh_type = FUFH_RDWR;
}
return fuse_filehandle_get(vp, fufh_type, fufhp);
}
void
fuse_filehandle_init(struct vnode *vp,
fufh_type_t fufh_type,
struct fuse_filehandle **fufhp,
uint64_t fh_id)
{
struct fuse_vnode_data *fvdat = VTOFUD(vp);
struct fuse_filehandle *fufh;
FS_DEBUG("id=%jd type=%d\n", (intmax_t)fh_id, fufh_type);
fufh = &(fvdat->fufh[fufh_type]);
MPASS(!FUFH_IS_VALID(fufh));
fufh->fh_id = fh_id;
fufh->fh_type = fufh_type;
if (!FUFH_IS_VALID(fufh)) {
panic("FUSE: init: invalid filehandle id (type=%d)", fufh_type);
}
if (fufhp != NULL)
*fufhp = fufh;
atomic_add_acq_int(&fuse_fh_count, 1);
}