xref: /freebsd/tests/sys/fs/fusefs/mockfs.hh (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 
31 extern "C" {
32 #include <sys/types.h>
33 
34 #include <pthread.h>
35 
36 #include "fuse_kernel.h"
37 }
38 
39 #include <gmock/gmock.h>
40 
41 #define TIME_T_MAX (std::numeric_limits<time_t>::max())
42 
43 /*
44  * A pseudo-fuse errno used indicate that a fuse operation should have no
45  * response, at least not immediately
46  */
47 #define FUSE_NORESPONSE 9999
48 
49 #define SET_OUT_HEADER_LEN(out, variant) { \
50 	(out).header.len = (sizeof((out).header) + \
51 			    sizeof((out).body.variant)); \
52 }
53 
54 /*
55  * Create an expectation on FUSE_LOOKUP and return it so the caller can set
56  * actions.
57  *
58  * This must be a macro instead of a method because EXPECT_CALL returns a type
59  * with a deleted constructor.
60  */
61 #define EXPECT_LOOKUP(parent, path)					\
62 	EXPECT_CALL(*m_mock, process(					\
63 		ResultOf([=](auto in) {					\
64 			return (in.header.opcode == FUSE_LOOKUP &&	\
65 				in.header.nodeid == (parent) &&	\
66 				strcmp(in.body.lookup, (path)) == 0);	\
67 		}, Eq(true)),						\
68 		_)							\
69 	)
70 
71 extern int verbosity;
72 
73 /*
74  * The maximum that a test case can set max_write, limited by the buffer
75  * supplied when reading from /dev/fuse.  This limitation is imposed by
76  * fusefs-libs, but not by the FUSE protocol.
77  */
78 const uint32_t max_max_write = 0x20000;
79 
80 
81 /* This struct isn't defined by fuse_kernel.h or libfuse, but it should be */
82 struct fuse_create_out {
83 	struct fuse_entry_out	entry;
84 	struct fuse_open_out	open;
85 };
86 
87 /* Protocol 7.8 version of struct fuse_attr */
88 struct fuse_attr_7_8
89 {
90 	uint64_t	ino;
91 	uint64_t	size;
92 	uint64_t	blocks;
93 	uint64_t	atime;
94 	uint64_t	mtime;
95 	uint64_t	ctime;
96 	uint32_t	atimensec;
97 	uint32_t	mtimensec;
98 	uint32_t	ctimensec;
99 	uint32_t	mode;
100 	uint32_t	nlink;
101 	uint32_t	uid;
102 	uint32_t	gid;
103 	uint32_t	rdev;
104 };
105 
106 /* Protocol 7.8 version of struct fuse_attr_out */
107 struct fuse_attr_out_7_8
108 {
109 	uint64_t	attr_valid;
110 	uint32_t	attr_valid_nsec;
111 	uint32_t	dummy;
112 	struct fuse_attr_7_8 attr;
113 };
114 
115 /* Protocol 7.8 version of struct fuse_entry_out */
116 struct fuse_entry_out_7_8 {
117 	uint64_t	nodeid;		/* Inode ID */
118 	uint64_t	generation;	/* Inode generation: nodeid:gen must
119 				   be unique for the fs's lifetime */
120 	uint64_t	entry_valid;	/* Cache timeout for the name */
121 	uint64_t	attr_valid;	/* Cache timeout for the attributes */
122 	uint32_t	entry_valid_nsec;
123 	uint32_t	attr_valid_nsec;
124 	struct fuse_attr_7_8 attr;
125 };
126 
127 /* Output struct for FUSE_CREATE for protocol 7.8 servers */
128 struct fuse_create_out_7_8 {
129 	struct fuse_entry_out_7_8	entry;
130 	struct fuse_open_out	open;
131 };
132 
133 /* Output struct for FUSE_INIT for protocol 7.22 and earlier servers */
134 struct fuse_init_out_7_22 {
135 	uint32_t	major;
136 	uint32_t	minor;
137 	uint32_t	max_readahead;
138 	uint32_t	flags;
139 	uint16_t	max_background;
140 	uint16_t	congestion_threshold;
141 	uint32_t	max_write;
142 };
143 
144 union fuse_payloads_in {
145 	fuse_access_in	access;
146 	fuse_bmap_in	bmap;
147 	/*
148 	 * In fusefs-libs 3.4.2 and below the buffer size is fixed at 0x21000
149 	 * minus the header sizes.  fusefs-libs 3.4.3 (and FUSE Protocol 7.29)
150 	 * add a FUSE_MAX_PAGES option that allows it to be greater.
151 	 *
152 	 * See fuse_kern_chan.c in fusefs-libs 2.9.9 and below, or
153 	 * FUSE_DEFAULT_MAX_PAGES_PER_REQ in fusefs-libs 3.4.3 and above.
154 	 */
155 	uint8_t		bytes[
156 	    max_max_write + 0x1000 - sizeof(struct fuse_in_header)
157 	];
158 	fuse_copy_file_range_in	copy_file_range;
159 	fuse_create_in	create;
160 	fuse_fallocate_in fallocate;
161 	fuse_flush_in	flush;
162 	fuse_fsync_in	fsync;
163 	fuse_fsync_in	fsyncdir;
164 	fuse_forget_in	forget;
165 	fuse_getattr_in	getattr;
166 	fuse_interrupt_in interrupt;
167 	fuse_lk_in	getlk;
168 	fuse_getxattr_in getxattr;
169 	fuse_init_in	init;
170 	fuse_link_in	link;
171 	fuse_listxattr_in listxattr;
172 	char		lookup[0];
173 	fuse_lseek_in	lseek;
174 	fuse_mkdir_in	mkdir;
175 	fuse_mknod_in	mknod;
176 	fuse_open_in	open;
177 	fuse_open_in	opendir;
178 	fuse_read_in	read;
179 	fuse_read_in	readdir;
180 	fuse_release_in	release;
181 	fuse_release_in	releasedir;
182 	fuse_rename_in	rename;
183 	char		rmdir[0];
184 	fuse_setattr_in	setattr;
185 	fuse_setxattr_in setxattr;
186 	fuse_lk_in	setlk;
187 	fuse_lk_in	setlkw;
188 	char		unlink[0];
189 	fuse_write_in	write;
190 };
191 
192 struct mockfs_buf_in {
193 	fuse_in_header		header;
194 	union fuse_payloads_in	body;
195 };
196 
197 union fuse_payloads_out {
198 	fuse_attr_out		attr;
199 	fuse_attr_out_7_8	attr_7_8;
200 	fuse_bmap_out		bmap;
201 	fuse_create_out		create;
202 	fuse_create_out_7_8	create_7_8;
203 	/*
204 	 * The protocol places no limits on the size of bytes.  Choose
205 	 * a size big enough for anything we'll test.
206 	 */
207 	uint8_t			bytes[0x40000];
208 	fuse_entry_out		entry;
209 	fuse_entry_out_7_8	entry_7_8;
210 	fuse_lk_out		getlk;
211 	fuse_getxattr_out	getxattr;
212 	fuse_init_out		init;
213 	fuse_init_out_7_22	init_7_22;
214 	fuse_lseek_out		lseek;
215 	/* The inval_entry structure should be followed by the entry's name */
216 	fuse_notify_inval_entry_out	inval_entry;
217 	fuse_notify_inval_inode_out	inval_inode;
218 	/* The store structure should be followed by the data to store */
219 	fuse_notify_store_out		store;
220 	fuse_listxattr_out	listxattr;
221 	fuse_open_out		open;
222 	fuse_statfs_out		statfs;
223 	/*
224 	 * The protocol places no limits on the length of the string.  This is
225 	 * merely convenient for testing.
226 	 */
227 	char			str[80];
228 	fuse_write_out		write;
229 };
230 
231 struct mockfs_buf_out {
232 	fuse_out_header		header;
233 	union fuse_payloads_out	body;
234 	/* the expected errno of the write to /dev/fuse */
235 	int			expected_errno;
236 
237 	/* Default constructor: zero everything */
238 	mockfs_buf_out() {
239 		memset(this, 0, sizeof(*this));
240 	}
241 };
242 
243 /* A function that can be invoked in place of MockFS::process */
244 typedef std::function<void (const mockfs_buf_in& in,
245 			    std::vector<std::unique_ptr<mockfs_buf_out>> &out)>
246 ProcessMockerT;
247 
248 /*
249  * Helper function used for setting an error expectation for any fuse operation.
250  * The operation will return the supplied error
251  */
252 ProcessMockerT ReturnErrno(int error);
253 
254 /* Helper function used for returning negative cache entries for LOOKUP */
255 ProcessMockerT ReturnNegativeCache(const struct timespec *entry_valid);
256 
257 /* Helper function used for returning a single immediate response */
258 ProcessMockerT ReturnImmediate(
259 	std::function<void(const mockfs_buf_in& in,
260 			   struct mockfs_buf_out &out)> f);
261 
262 /* How the daemon should check /dev/fuse for readiness */
263 enum poll_method {
264 	BLOCKING,
265 	SELECT,
266 	POLL,
267 	KQ
268 };
269 
270 /*
271  * Fake FUSE filesystem
272  *
273  * "Mounts" a filesystem to a temporary directory and services requests
274  * according to the programmed expectations.
275  *
276  * Operates directly on the fusefs(4) kernel API, not the libfuse(3) user api.
277  */
278 class MockFS {
279 	/*
280 	 * thread id of the fuse daemon thread
281 	 *
282 	 * It must run in a separate thread so it doesn't deadlock with the
283 	 * client test code.
284 	 */
285 	pthread_t m_daemon_id;
286 
287 	/* file descriptor of /dev/fuse control device */
288 	volatile int m_fuse_fd;
289 
290 	/* The minor version of the kernel API that this mock daemon targets */
291 	uint32_t m_kernel_minor_version;
292 
293 	int m_kq;
294 
295 	/* The max_readahead file system option */
296 	uint32_t m_maxreadahead;
297 
298 	/* pid of the test process */
299 	pid_t m_pid;
300 
301 	/* The unique value of the header of the last received operation */
302 	uint64_t m_last_unique;
303 
304 	/* Method the daemon should use for I/O to and from /dev/fuse */
305 	enum poll_method m_pm;
306 
307 	/* Timestamp granularity in nanoseconds */
308 	unsigned m_time_gran;
309 
310 	void audit_request(const mockfs_buf_in &in, ssize_t buflen);
311 	void debug_request(const mockfs_buf_in&, ssize_t buflen);
312 	void debug_response(const mockfs_buf_out&);
313 
314 	/* Initialize a session after mounting */
315 	void init(uint32_t flags);
316 
317 	/* Is pid from a process that might be involved in the test? */
318 	bool pid_ok(pid_t pid);
319 
320 	/* Default request handler */
321 	void process_default(const mockfs_buf_in&,
322 		std::vector<std::unique_ptr<mockfs_buf_out>>&);
323 
324 	/* Entry point for the daemon thread */
325 	static void* service(void*);
326 
327 	/*
328 	 * Read, but do not process, a single request from the kernel
329 	 *
330 	 * @param in	Return storage for the FUSE request
331 	 * @param res	Return value of read(2).  If positive, the amount of
332 	 *		data read from the fuse device.
333 	 */
334 	void read_request(mockfs_buf_in& in, ssize_t& res);
335 
336 	public:
337 	/* Write a single response back to the kernel */
338 	void write_response(const mockfs_buf_out &out);
339 
340 	/* pid of child process, for two-process test cases */
341 	pid_t m_child_pid;
342 
343 	/* Maximum size of a FUSE_WRITE write */
344 	uint32_t m_maxwrite;
345 
346 	/*
347 	 * Number of events that were available from /dev/fuse after the last
348 	 * kevent call.  Only valid when m_pm = KQ.
349 	 */
350 	int m_nready;
351 
352 	/* Tell the daemon to shut down ASAP */
353 	bool m_quit;
354 
355 	/* Create a new mockfs and mount it to a tempdir */
356 	MockFS(int max_readahead, bool allow_other,
357 		bool default_permissions, bool push_symlinks_in, bool ro,
358 		enum poll_method pm, uint32_t flags,
359 		uint32_t kernel_minor_version, uint32_t max_write, bool async,
360 		bool no_clusterr, unsigned time_gran, bool nointr,
361 		bool noatime, const char *fsname, const char *subtype);
362 
363 	virtual ~MockFS();
364 
365 	/* Kill the filesystem daemon without unmounting the filesystem */
366 	void kill_daemon();
367 
368 	/* Process FUSE requests endlessly */
369 	void loop();
370 
371 	/*
372 	 * Send an asynchronous notification to invalidate a directory entry.
373 	 * Similar to libfuse's fuse_lowlevel_notify_inval_entry
374 	 *
375 	 * This method will block until the client has responded, so it should
376 	 * generally be run in a separate thread from request processing.
377 	 *
378 	 * @param	parent	Parent directory's inode number
379 	 * @param	name	name of dirent to invalidate
380 	 * @param	namelen	size of name, including the NUL
381 	 */
382 	int notify_inval_entry(ino_t parent, const char *name, size_t namelen);
383 
384 	/*
385 	 * Send an asynchronous notification to invalidate an inode's cached
386 	 * data and/or attributes.  Similar to libfuse's
387 	 * fuse_lowlevel_notify_inval_inode.
388 	 *
389 	 * This method will block until the client has responded, so it should
390 	 * generally be run in a separate thread from request processing.
391 	 *
392 	 * @param	ino	File's inode number
393 	 * @param	off	offset at which to begin invalidation.  A
394 	 * 			negative offset means to invalidate attributes
395 	 * 			only.
396 	 * @param	len	Size of region of data to invalidate.  0 means
397 	 * 			to invalidate all cached data.
398 	 */
399 	int notify_inval_inode(ino_t ino, off_t off, ssize_t len);
400 
401 	/*
402 	 * Send an asynchronous notification to store data directly into an
403 	 * inode's cache.  Similar to libfuse's fuse_lowlevel_notify_store.
404 	 *
405 	 * This method will block until the client has responded, so it should
406 	 * generally be run in a separate thread from request processing.
407 	 *
408 	 * @param	ino	File's inode number
409 	 * @param	off	Offset at which to store data
410 	 * @param	data	Pointer to the data to cache
411 	 * @param	len	Size of data
412 	 */
413 	int notify_store(ino_t ino, off_t off, const void* data, ssize_t size);
414 
415 	/*
416 	 * Request handler
417 	 *
418 	 * This method is expected to provide the responses to each FUSE
419 	 * operation.  For an immediate response, push one buffer into out.
420 	 * For a delayed response, push nothing.  For an immediate response
421 	 * plus a delayed response to an earlier operation, push two bufs.
422 	 * Test cases must define each response using Googlemock expectations
423 	 */
424 	MOCK_METHOD2(process, void(const mockfs_buf_in&,
425 				std::vector<std::unique_ptr<mockfs_buf_out>>&));
426 
427 	/* Gracefully unmount */
428 	void unmount();
429 };
430