xref: /freebsd/tests/sys/fs/fusefs/mockfs.hh (revision d9a42747950146bf03cda7f6e25d219253f8a57a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2019 The FreeBSD Foundation
5  *
6  * This software was developed by BFF Storage Systems, LLC under sponsorship
7  * from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 extern "C" {
34 #include <sys/types.h>
35 
36 #include <pthread.h>
37 
38 #include "fuse_kernel.h"
39 }
40 
41 #include <gmock/gmock.h>
42 
43 #define TIME_T_MAX (std::numeric_limits<time_t>::max())
44 
45 /*
46  * A pseudo-fuse errno used indicate that a fuse operation should have no
47  * response, at least not immediately
48  */
49 #define FUSE_NORESPONSE 9999
50 
51 #define SET_OUT_HEADER_LEN(out, variant) { \
52 	(out).header.len = (sizeof((out).header) + \
53 			    sizeof((out).body.variant)); \
54 }
55 
56 /*
57  * Create an expectation on FUSE_LOOKUP and return it so the caller can set
58  * actions.
59  *
60  * This must be a macro instead of a method because EXPECT_CALL returns a type
61  * with a deleted constructor.
62  */
63 #define EXPECT_LOOKUP(parent, path)					\
64 	EXPECT_CALL(*m_mock, process(					\
65 		ResultOf([=](auto in) {					\
66 			return (in.header.opcode == FUSE_LOOKUP &&	\
67 				in.header.nodeid == (parent) &&	\
68 				strcmp(in.body.lookup, (path)) == 0);	\
69 		}, Eq(true)),						\
70 		_)							\
71 	)
72 
73 extern int verbosity;
74 
75 /*
76  * The maximum that a test case can set max_write, limited by the buffer
77  * supplied when reading from /dev/fuse.  This limitation is imposed by
78  * fusefs-libs, but not by the FUSE protocol.
79  */
80 const uint32_t max_max_write = 0x20000;
81 
82 
83 /* This struct isn't defined by fuse_kernel.h or libfuse, but it should be */
84 struct fuse_create_out {
85 	struct fuse_entry_out	entry;
86 	struct fuse_open_out	open;
87 };
88 
89 /* Protocol 7.8 version of struct fuse_attr */
90 struct fuse_attr_7_8
91 {
92 	uint64_t	ino;
93 	uint64_t	size;
94 	uint64_t	blocks;
95 	uint64_t	atime;
96 	uint64_t	mtime;
97 	uint64_t	ctime;
98 	uint32_t	atimensec;
99 	uint32_t	mtimensec;
100 	uint32_t	ctimensec;
101 	uint32_t	mode;
102 	uint32_t	nlink;
103 	uint32_t	uid;
104 	uint32_t	gid;
105 	uint32_t	rdev;
106 };
107 
108 /* Protocol 7.8 version of struct fuse_attr_out */
109 struct fuse_attr_out_7_8
110 {
111 	uint64_t	attr_valid;
112 	uint32_t	attr_valid_nsec;
113 	uint32_t	dummy;
114 	struct fuse_attr_7_8 attr;
115 };
116 
117 /* Protocol 7.8 version of struct fuse_entry_out */
118 struct fuse_entry_out_7_8 {
119 	uint64_t	nodeid;		/* Inode ID */
120 	uint64_t	generation;	/* Inode generation: nodeid:gen must
121 				   be unique for the fs's lifetime */
122 	uint64_t	entry_valid;	/* Cache timeout for the name */
123 	uint64_t	attr_valid;	/* Cache timeout for the attributes */
124 	uint32_t	entry_valid_nsec;
125 	uint32_t	attr_valid_nsec;
126 	struct fuse_attr_7_8 attr;
127 };
128 
129 /* Output struct for FUSE_CREATE for protocol 7.8 servers */
130 struct fuse_create_out_7_8 {
131 	struct fuse_entry_out_7_8	entry;
132 	struct fuse_open_out	open;
133 };
134 
135 /* Output struct for FUSE_INIT for protocol 7.22 and earlier servers */
136 struct fuse_init_out_7_22 {
137 	uint32_t	major;
138 	uint32_t	minor;
139 	uint32_t	max_readahead;
140 	uint32_t	flags;
141 	uint16_t	max_background;
142 	uint16_t	congestion_threshold;
143 	uint32_t	max_write;
144 };
145 
146 union fuse_payloads_in {
147 	fuse_access_in	access;
148 	fuse_bmap_in	bmap;
149 	/*
150 	 * In fusefs-libs 3.4.2 and below the buffer size is fixed at 0x21000
151 	 * minus the header sizes.  fusefs-libs 3.4.3 (and FUSE Protocol 7.29)
152 	 * add a FUSE_MAX_PAGES option that allows it to be greater.
153 	 *
154 	 * See fuse_kern_chan.c in fusefs-libs 2.9.9 and below, or
155 	 * FUSE_DEFAULT_MAX_PAGES_PER_REQ in fusefs-libs 3.4.3 and above.
156 	 */
157 	uint8_t		bytes[
158 	    max_max_write + 0x1000 - sizeof(struct fuse_in_header)
159 	];
160 	fuse_copy_file_range_in	copy_file_range;
161 	fuse_create_in	create;
162 	fuse_fallocate_in fallocate;
163 	fuse_flush_in	flush;
164 	fuse_fsync_in	fsync;
165 	fuse_fsync_in	fsyncdir;
166 	fuse_forget_in	forget;
167 	fuse_getattr_in	getattr;
168 	fuse_interrupt_in interrupt;
169 	fuse_lk_in	getlk;
170 	fuse_getxattr_in getxattr;
171 	fuse_init_in	init;
172 	fuse_link_in	link;
173 	fuse_listxattr_in listxattr;
174 	char		lookup[0];
175 	fuse_lseek_in	lseek;
176 	fuse_mkdir_in	mkdir;
177 	fuse_mknod_in	mknod;
178 	fuse_open_in	open;
179 	fuse_open_in	opendir;
180 	fuse_read_in	read;
181 	fuse_read_in	readdir;
182 	fuse_release_in	release;
183 	fuse_release_in	releasedir;
184 	fuse_rename_in	rename;
185 	char		rmdir[0];
186 	fuse_setattr_in	setattr;
187 	fuse_setxattr_in setxattr;
188 	fuse_lk_in	setlk;
189 	fuse_lk_in	setlkw;
190 	char		unlink[0];
191 	fuse_write_in	write;
192 };
193 
194 struct mockfs_buf_in {
195 	fuse_in_header		header;
196 	union fuse_payloads_in	body;
197 };
198 
199 union fuse_payloads_out {
200 	fuse_attr_out		attr;
201 	fuse_attr_out_7_8	attr_7_8;
202 	fuse_bmap_out		bmap;
203 	fuse_create_out		create;
204 	fuse_create_out_7_8	create_7_8;
205 	/*
206 	 * The protocol places no limits on the size of bytes.  Choose
207 	 * a size big enough for anything we'll test.
208 	 */
209 	uint8_t			bytes[0x40000];
210 	fuse_entry_out		entry;
211 	fuse_entry_out_7_8	entry_7_8;
212 	fuse_lk_out		getlk;
213 	fuse_getxattr_out	getxattr;
214 	fuse_init_out		init;
215 	fuse_init_out_7_22	init_7_22;
216 	fuse_lseek_out		lseek;
217 	/* The inval_entry structure should be followed by the entry's name */
218 	fuse_notify_inval_entry_out	inval_entry;
219 	fuse_notify_inval_inode_out	inval_inode;
220 	/* The store structure should be followed by the data to store */
221 	fuse_notify_store_out		store;
222 	fuse_listxattr_out	listxattr;
223 	fuse_open_out		open;
224 	fuse_statfs_out		statfs;
225 	/*
226 	 * The protocol places no limits on the length of the string.  This is
227 	 * merely convenient for testing.
228 	 */
229 	char			str[80];
230 	fuse_write_out		write;
231 };
232 
233 struct mockfs_buf_out {
234 	fuse_out_header		header;
235 	union fuse_payloads_out	body;
236 	/* the expected errno of the write to /dev/fuse */
237 	int			expected_errno;
238 
239 	/* Default constructor: zero everything */
240 	mockfs_buf_out() {
241 		memset(this, 0, sizeof(*this));
242 	}
243 };
244 
245 /* A function that can be invoked in place of MockFS::process */
246 typedef std::function<void (const mockfs_buf_in& in,
247 			    std::vector<std::unique_ptr<mockfs_buf_out>> &out)>
248 ProcessMockerT;
249 
250 /*
251  * Helper function used for setting an error expectation for any fuse operation.
252  * The operation will return the supplied error
253  */
254 ProcessMockerT ReturnErrno(int error);
255 
256 /* Helper function used for returning negative cache entries for LOOKUP */
257 ProcessMockerT ReturnNegativeCache(const struct timespec *entry_valid);
258 
259 /* Helper function used for returning a single immediate response */
260 ProcessMockerT ReturnImmediate(
261 	std::function<void(const mockfs_buf_in& in,
262 			   struct mockfs_buf_out &out)> f);
263 
264 /* How the daemon should check /dev/fuse for readiness */
265 enum poll_method {
266 	BLOCKING,
267 	SELECT,
268 	POLL,
269 	KQ
270 };
271 
272 /*
273  * Fake FUSE filesystem
274  *
275  * "Mounts" a filesystem to a temporary directory and services requests
276  * according to the programmed expectations.
277  *
278  * Operates directly on the fusefs(4) kernel API, not the libfuse(3) user api.
279  */
280 class MockFS {
281 	/*
282 	 * thread id of the fuse daemon thread
283 	 *
284 	 * It must run in a separate thread so it doesn't deadlock with the
285 	 * client test code.
286 	 */
287 	pthread_t m_daemon_id;
288 
289 	/* file descriptor of /dev/fuse control device */
290 	volatile int m_fuse_fd;
291 
292 	/* The minor version of the kernel API that this mock daemon targets */
293 	uint32_t m_kernel_minor_version;
294 
295 	int m_kq;
296 
297 	/* The max_readahead file system option */
298 	uint32_t m_maxreadahead;
299 
300 	/* pid of the test process */
301 	pid_t m_pid;
302 
303 	/* The unique value of the header of the last received operation */
304 	uint64_t m_last_unique;
305 
306 	/* Method the daemon should use for I/O to and from /dev/fuse */
307 	enum poll_method m_pm;
308 
309 	/* Timestamp granularity in nanoseconds */
310 	unsigned m_time_gran;
311 
312 	void audit_request(const mockfs_buf_in &in, ssize_t buflen);
313 	void debug_request(const mockfs_buf_in&, ssize_t buflen);
314 	void debug_response(const mockfs_buf_out&);
315 
316 	/* Initialize a session after mounting */
317 	void init(uint32_t flags);
318 
319 	/* Is pid from a process that might be involved in the test? */
320 	bool pid_ok(pid_t pid);
321 
322 	/* Default request handler */
323 	void process_default(const mockfs_buf_in&,
324 		std::vector<std::unique_ptr<mockfs_buf_out>>&);
325 
326 	/* Entry point for the daemon thread */
327 	static void* service(void*);
328 
329 	/*
330 	 * Read, but do not process, a single request from the kernel
331 	 *
332 	 * @param in	Return storage for the FUSE request
333 	 * @param res	Return value of read(2).  If positive, the amount of
334 	 *		data read from the fuse device.
335 	 */
336 	void read_request(mockfs_buf_in& in, ssize_t& res);
337 
338 	public:
339 	/* Write a single response back to the kernel */
340 	void write_response(const mockfs_buf_out &out);
341 
342 	/* pid of child process, for two-process test cases */
343 	pid_t m_child_pid;
344 
345 	/* Maximum size of a FUSE_WRITE write */
346 	uint32_t m_maxwrite;
347 
348 	/*
349 	 * Number of events that were available from /dev/fuse after the last
350 	 * kevent call.  Only valid when m_pm = KQ.
351 	 */
352 	int m_nready;
353 
354 	/* Tell the daemon to shut down ASAP */
355 	bool m_quit;
356 
357 	/* Create a new mockfs and mount it to a tempdir */
358 	MockFS(int max_readahead, bool allow_other,
359 		bool default_permissions, bool push_symlinks_in, bool ro,
360 		enum poll_method pm, uint32_t flags,
361 		uint32_t kernel_minor_version, uint32_t max_write, bool async,
362 		bool no_clusterr, unsigned time_gran, bool nointr,
363 		bool noatime, const char *fsname, const char *subtype);
364 
365 	virtual ~MockFS();
366 
367 	/* Kill the filesystem daemon without unmounting the filesystem */
368 	void kill_daemon();
369 
370 	/* Process FUSE requests endlessly */
371 	void loop();
372 
373 	/*
374 	 * Send an asynchronous notification to invalidate a directory entry.
375 	 * Similar to libfuse's fuse_lowlevel_notify_inval_entry
376 	 *
377 	 * This method will block until the client has responded, so it should
378 	 * generally be run in a separate thread from request processing.
379 	 *
380 	 * @param	parent	Parent directory's inode number
381 	 * @param	name	name of dirent to invalidate
382 	 * @param	namelen	size of name, including the NUL
383 	 */
384 	int notify_inval_entry(ino_t parent, const char *name, size_t namelen);
385 
386 	/*
387 	 * Send an asynchronous notification to invalidate an inode's cached
388 	 * data and/or attributes.  Similar to libfuse's
389 	 * fuse_lowlevel_notify_inval_inode.
390 	 *
391 	 * This method will block until the client has responded, so it should
392 	 * generally be run in a separate thread from request processing.
393 	 *
394 	 * @param	ino	File's inode number
395 	 * @param	off	offset at which to begin invalidation.  A
396 	 * 			negative offset means to invalidate attributes
397 	 * 			only.
398 	 * @param	len	Size of region of data to invalidate.  0 means
399 	 * 			to invalidate all cached data.
400 	 */
401 	int notify_inval_inode(ino_t ino, off_t off, ssize_t len);
402 
403 	/*
404 	 * Send an asynchronous notification to store data directly into an
405 	 * inode's cache.  Similar to libfuse's fuse_lowlevel_notify_store.
406 	 *
407 	 * This method will block until the client has responded, so it should
408 	 * generally be run in a separate thread from request processing.
409 	 *
410 	 * @param	ino	File's inode number
411 	 * @param	off	Offset at which to store data
412 	 * @param	data	Pointer to the data to cache
413 	 * @param	len	Size of data
414 	 */
415 	int notify_store(ino_t ino, off_t off, const void* data, ssize_t size);
416 
417 	/*
418 	 * Request handler
419 	 *
420 	 * This method is expected to provide the responses to each FUSE
421 	 * operation.  For an immediate response, push one buffer into out.
422 	 * For a delayed response, push nothing.  For an immediate response
423 	 * plus a delayed response to an earlier operation, push two bufs.
424 	 * Test cases must define each response using Googlemock expectations
425 	 */
426 	MOCK_METHOD2(process, void(const mockfs_buf_in&,
427 				std::vector<std::unique_ptr<mockfs_buf_out>>&));
428 
429 	/* Gracefully unmount */
430 	void unmount();
431 };
432