opnsense-src/tests/sys/fs/fusefs/bmap.cc
Alan Somers bdd7a3f2a1 fusefs: fix a recurse-on-non-recursive lockmgr panic
fuse_vnop_bmap needs to know the file's size in order to calculate the
optimum amount of readahead.  If the file's size is unknown, it must ask
the FUSE server.  But if the file's data was previously cached and the
server reports that its size has shrunk, fusefs must invalidate the
cached data.  That's not possible during VOP_BMAP because the buffer
object is already locked.

Fix the panic by not querying the FUSE server for the file's size during
VOP_BMAP if we don't need it.  That's also a a slight performance
optimization.

PR:		256937
Reported by:	Agata <chogata@moosefs.pro>
Tested by:	Agata <chogata@moosefs.pro>

(cherry picked from commit 7430017b99)
2021-12-06 22:08:32 -07:00

253 lines
7.1 KiB
C++

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2019 The FreeBSD Foundation
*
* This software was 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 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.
*
* $FreeBSD$
*/
extern "C" {
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/filio.h>
#include <fcntl.h>
}
#include "mockfs.hh"
#include "utils.hh"
using namespace testing;
const static char FULLPATH[] = "mountpoint/foo";
const static char RELPATH[] = "foo";
class Bmap: public FuseTest {
public:
virtual void SetUp() {
m_maxreadahead = UINT32_MAX;
FuseTest::SetUp();
}
void expect_bmap(uint64_t ino, uint64_t lbn, uint32_t blocksize, uint64_t pbn)
{
EXPECT_CALL(*m_mock, process(
ResultOf([=](auto in) {
return (in.header.opcode == FUSE_BMAP &&
in.header.nodeid == ino &&
in.body.bmap.block == lbn &&
in.body.bmap.blocksize == blocksize);
}, Eq(true)),
_)
).WillOnce(Invoke(ReturnImmediate([=](auto i __unused, auto& out) {
SET_OUT_HEADER_LEN(out, bmap);
out.body.bmap.block = pbn;
})));
}
void expect_lookup(const char *relpath, uint64_t ino, off_t size)
{
FuseTest::expect_lookup(relpath, ino, S_IFREG | 0644, size, 1,
UINT64_MAX);
}
};
class BmapEof: public Bmap, public WithParamInterface<int> {};
/*
* Test FUSE_BMAP
* XXX The FUSE protocol does not include the runp and runb variables, so those
* must be guessed in-kernel.
*/
TEST_F(Bmap, bmap)
{
struct fiobmap2_arg arg;
/*
* Pick fsize and lbn large enough that max length runs won't reach
* either beginning or end of file
*/
const off_t filesize = 1 << 30;
int64_t lbn = 100;
int64_t pbn = 12345;
const ino_t ino = 42;
int fd;
expect_lookup(RELPATH, 42, filesize);
expect_open(ino, 0, 1);
expect_bmap(ino, lbn, m_maxbcachebuf, pbn);
fd = open(FULLPATH, O_RDWR);
ASSERT_LE(0, fd) << strerror(errno);
arg.bn = lbn;
arg.runp = -1;
arg.runb = -1;
ASSERT_EQ(0, ioctl(fd, FIOBMAP2, &arg)) << strerror(errno);
EXPECT_EQ(arg.bn, pbn);
EXPECT_EQ(arg.runp, m_maxphys / m_maxbcachebuf - 1);
EXPECT_EQ(arg.runb, m_maxphys / m_maxbcachebuf - 1);
}
/*
* If the daemon does not implement VOP_BMAP, fusefs should return sensible
* defaults.
*/
TEST_F(Bmap, default_)
{
struct fiobmap2_arg arg;
const off_t filesize = 1 << 30;
const ino_t ino = 42;
int64_t lbn;
int fd;
expect_lookup(RELPATH, 42, filesize);
expect_open(ino, 0, 1);
EXPECT_CALL(*m_mock, process(
ResultOf([=](auto in) {
return (in.header.opcode == FUSE_BMAP);
}, Eq(true)),
_)
).WillOnce(Invoke(ReturnErrno(ENOSYS)));
fd = open(FULLPATH, O_RDWR);
ASSERT_LE(0, fd) << strerror(errno);
/* First block */
lbn = 0;
arg.bn = lbn;
arg.runp = -1;
arg.runb = -1;
ASSERT_EQ(0, ioctl(fd, FIOBMAP2, &arg)) << strerror(errno);
EXPECT_EQ(arg.bn, 0);
EXPECT_EQ(arg.runp, m_maxphys / m_maxbcachebuf - 1);
EXPECT_EQ(arg.runb, 0);
/* In the middle */
lbn = filesize / m_maxbcachebuf / 2;
arg.bn = lbn;
arg.runp = -1;
arg.runb = -1;
ASSERT_EQ(0, ioctl(fd, FIOBMAP2, &arg)) << strerror(errno);
EXPECT_EQ(arg.bn, lbn * m_maxbcachebuf / DEV_BSIZE);
EXPECT_EQ(arg.runp, m_maxphys / m_maxbcachebuf - 1);
EXPECT_EQ(arg.runb, m_maxphys / m_maxbcachebuf - 1);
/* Last block */
lbn = filesize / m_maxbcachebuf - 1;
arg.bn = lbn;
arg.runp = -1;
arg.runb = -1;
ASSERT_EQ(0, ioctl(fd, FIOBMAP2, &arg)) << strerror(errno);
EXPECT_EQ(arg.bn, lbn * m_maxbcachebuf / DEV_BSIZE);
EXPECT_EQ(arg.runp, 0);
EXPECT_EQ(arg.runb, m_maxphys / m_maxbcachebuf - 1);
leak(fd);
}
/*
* VOP_BMAP should not query the server for the file's size, even if its cached
* attributes have expired.
* Regression test for https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=256937
*/
TEST_P(BmapEof, eof)
{
/*
* Outline:
* 1) lookup the file, setting attr_valid=0
* 2) Read more than one block, causing the kernel to issue VOP_BMAP to
* plan readahead.
* 3) Nothing should panic
* 4) Repeat the tests, truncating the file after different numbers of
* GETATTR operations.
*/
Sequence seq;
const off_t filesize = 2 * m_maxbcachebuf;
const ino_t ino = 42;
mode_t mode = S_IFREG | 0644;
void *contents, *buf;
int fd;
int ngetattrs;
ngetattrs = GetParam();
contents = calloc(1, filesize);
FuseTest::expect_lookup(RELPATH, ino, mode, filesize, 1, 0);
expect_open(ino, 0, 1);
// Depending on ngetattrs, FUSE_READ could be called with either
// filesize or filesize / 2 .
EXPECT_CALL(*m_mock, process(
ResultOf([=](auto in) {
return (in.header.opcode == FUSE_READ &&
in.header.nodeid == ino &&
in.body.read.offset == 0 &&
( in.body.read.size == filesize ||
in.body.read.size == filesize / 2));
}, Eq(true)),
_)
).WillOnce(Invoke(ReturnImmediate([=](auto in, auto& out) {
size_t osize = in.body.read.size;
out.header.len = sizeof(struct fuse_out_header) + osize;
bzero(out.body.bytes, osize);
})));
EXPECT_CALL(*m_mock, process(
ResultOf([](auto in) {
return (in.header.opcode == FUSE_GETATTR &&
in.header.nodeid == ino);
}, Eq(true)),
_)
).Times(Between(ngetattrs - 1, ngetattrs))
.InSequence(seq)
.WillRepeatedly(Invoke(ReturnImmediate([=](auto i __unused, auto& out) {
SET_OUT_HEADER_LEN(out, attr);
out.body.attr.attr_valid = 0;
out.body.attr.attr.ino = ino;
out.body.attr.attr.mode = S_IFREG | 0644;
out.body.attr.attr.size = filesize;
})));
EXPECT_CALL(*m_mock, process(
ResultOf([](auto in) {
return (in.header.opcode == FUSE_GETATTR &&
in.header.nodeid == ino);
}, Eq(true)),
_)
).InSequence(seq)
.WillRepeatedly(Invoke(ReturnImmediate([=](auto i __unused, auto& out) {
SET_OUT_HEADER_LEN(out, attr);
out.body.attr.attr_valid = 0;
out.body.attr.attr.ino = ino;
out.body.attr.attr.mode = S_IFREG | 0644;
out.body.attr.attr.size = filesize / 2;
})));
buf = calloc(1, filesize);
fd = open(FULLPATH, O_RDWR);
ASSERT_LE(0, fd) << strerror(errno);
read(fd, buf, filesize);
}
INSTANTIATE_TEST_CASE_P(BE, BmapEof,
Values(1, 2, 3)
);