xref: /freebsd/tests/sys/fs/fusefs/mockfs.hh (revision ec4deee4e4f2aef1b97d9424f25d04e91fd7dc10)
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 /* This struct isn't defined by fuse_kernel.h or libfuse, but it should be */
76 struct fuse_create_out {
77 	struct fuse_entry_out	entry;
78 	struct fuse_open_out	open;
79 };
80 
81 /* Protocol 7.8 version of struct fuse_attr */
82 struct fuse_attr_7_8
83 {
84 	uint64_t	ino;
85 	uint64_t	size;
86 	uint64_t	blocks;
87 	uint64_t	atime;
88 	uint64_t	mtime;
89 	uint64_t	ctime;
90 	uint32_t	atimensec;
91 	uint32_t	mtimensec;
92 	uint32_t	ctimensec;
93 	uint32_t	mode;
94 	uint32_t	nlink;
95 	uint32_t	uid;
96 	uint32_t	gid;
97 	uint32_t	rdev;
98 };
99 
100 /* Protocol 7.8 version of struct fuse_attr_out */
101 struct fuse_attr_out_7_8
102 {
103 	uint64_t	attr_valid;
104 	uint32_t	attr_valid_nsec;
105 	uint32_t	dummy;
106 	struct fuse_attr_7_8 attr;
107 };
108 
109 /* Protocol 7.8 version of struct fuse_entry_out */
110 struct fuse_entry_out_7_8 {
111 	uint64_t	nodeid;		/* Inode ID */
112 	uint64_t	generation;	/* Inode generation: nodeid:gen must
113 				   be unique for the fs's lifetime */
114 	uint64_t	entry_valid;	/* Cache timeout for the name */
115 	uint64_t	attr_valid;	/* Cache timeout for the attributes */
116 	uint32_t	entry_valid_nsec;
117 	uint32_t	attr_valid_nsec;
118 	struct fuse_attr_7_8 attr;
119 };
120 
121 /* Output struct for FUSE_CREATE for protocol 7.8 servers */
122 struct fuse_create_out_7_8 {
123 	struct fuse_entry_out_7_8	entry;
124 	struct fuse_open_out	open;
125 };
126 
127 /* Output struct for FUSE_INIT for protocol 7.22 and earlier servers */
128 struct fuse_init_out_7_22 {
129 	uint32_t	major;
130 	uint32_t	minor;
131 	uint32_t	max_readahead;
132 	uint32_t	flags;
133 	uint16_t	max_background;
134 	uint16_t	congestion_threshold;
135 	uint32_t	max_write;
136 };
137 
138 union fuse_payloads_in {
139 	fuse_access_in	access;
140 	fuse_bmap_in	bmap;
141 	/* value is from fuse_kern_chan.c in fusefs-libs */
142 	uint8_t		bytes[0x21000 - sizeof(struct fuse_in_header)];
143 	fuse_create_in	create;
144 	fuse_flush_in	flush;
145 	fuse_fsync_in	fsync;
146 	fuse_fsync_in	fsyncdir;
147 	fuse_forget_in	forget;
148 	fuse_getattr_in	getattr;
149 	fuse_interrupt_in interrupt;
150 	fuse_lk_in	getlk;
151 	fuse_getxattr_in getxattr;
152 	fuse_init_in	init;
153 	fuse_link_in	link;
154 	fuse_listxattr_in listxattr;
155 	char		lookup[0];
156 	fuse_mkdir_in	mkdir;
157 	fuse_mknod_in	mknod;
158 	fuse_open_in	open;
159 	fuse_open_in	opendir;
160 	fuse_read_in	read;
161 	fuse_read_in	readdir;
162 	fuse_release_in	release;
163 	fuse_release_in	releasedir;
164 	fuse_rename_in	rename;
165 	char		rmdir[0];
166 	fuse_setattr_in	setattr;
167 	fuse_setxattr_in setxattr;
168 	fuse_lk_in	setlk;
169 	fuse_lk_in	setlkw;
170 	char		unlink[0];
171 	fuse_write_in	write;
172 };
173 
174 struct mockfs_buf_in {
175 	fuse_in_header		header;
176 	union fuse_payloads_in	body;
177 };
178 
179 union fuse_payloads_out {
180 	fuse_attr_out		attr;
181 	fuse_attr_out_7_8	attr_7_8;
182 	fuse_bmap_out		bmap;
183 	fuse_create_out		create;
184 	fuse_create_out_7_8	create_7_8;
185 	/*
186 	 * The protocol places no limits on the size of bytes.  Choose
187 	 * a size big enough for anything we'll test.
188 	 */
189 	uint8_t			bytes[0x20000];
190 	fuse_entry_out		entry;
191 	fuse_entry_out_7_8	entry_7_8;
192 	fuse_lk_out		getlk;
193 	fuse_getxattr_out	getxattr;
194 	fuse_init_out		init;
195 	fuse_init_out_7_22	init_7_22;
196 	/* The inval_entry structure should be followed by the entry's name */
197 	fuse_notify_inval_entry_out	inval_entry;
198 	fuse_notify_inval_inode_out	inval_inode;
199 	/* The store structure should be followed by the data to store */
200 	fuse_notify_store_out		store;
201 	fuse_listxattr_out	listxattr;
202 	fuse_open_out		open;
203 	fuse_statfs_out		statfs;
204 	/*
205 	 * The protocol places no limits on the length of the string.  This is
206 	 * merely convenient for testing.
207 	 */
208 	char			str[80];
209 	fuse_write_out		write;
210 };
211 
212 struct mockfs_buf_out {
213 	fuse_out_header		header;
214 	union fuse_payloads_out	body;
215 
216 	/* Default constructor: zero everything */
217 	mockfs_buf_out() {
218 		memset(this, 0, sizeof(*this));
219 	}
220 };
221 
222 /* A function that can be invoked in place of MockFS::process */
223 typedef std::function<void (const mockfs_buf_in& in,
224 			    std::vector<std::unique_ptr<mockfs_buf_out>> &out)>
225 ProcessMockerT;
226 
227 /*
228  * Helper function used for setting an error expectation for any fuse operation.
229  * The operation will return the supplied error
230  */
231 ProcessMockerT ReturnErrno(int error);
232 
233 /* Helper function used for returning negative cache entries for LOOKUP */
234 ProcessMockerT ReturnNegativeCache(const struct timespec *entry_valid);
235 
236 /* Helper function used for returning a single immediate response */
237 ProcessMockerT ReturnImmediate(
238 	std::function<void(const mockfs_buf_in& in,
239 			   struct mockfs_buf_out &out)> f);
240 
241 /* How the daemon should check /dev/fuse for readiness */
242 enum poll_method {
243 	BLOCKING,
244 	SELECT,
245 	POLL,
246 	KQ
247 };
248 
249 /*
250  * Fake FUSE filesystem
251  *
252  * "Mounts" a filesystem to a temporary directory and services requests
253  * according to the programmed expectations.
254  *
255  * Operates directly on the fusefs(4) kernel API, not the libfuse(3) user api.
256  */
257 class MockFS {
258 	/*
259 	 * thread id of the fuse daemon thread
260 	 *
261 	 * It must run in a separate thread so it doesn't deadlock with the
262 	 * client test code.
263 	 */
264 	pthread_t m_daemon_id;
265 
266 	/* file descriptor of /dev/fuse control device */
267 	int m_fuse_fd;
268 
269 	/* The minor version of the kernel API that this mock daemon targets */
270 	uint32_t m_kernel_minor_version;
271 
272 	int m_kq;
273 
274 	/* The max_readahead file system option */
275 	uint32_t m_maxreadahead;
276 
277 	/* pid of the test process */
278 	pid_t m_pid;
279 
280 	/* Method the daemon should use for I/O to and from /dev/fuse */
281 	enum poll_method m_pm;
282 
283 	/* Timestamp granularity in nanoseconds */
284 	unsigned m_time_gran;
285 
286 	void audit_request(const mockfs_buf_in &in, ssize_t buflen);
287 	void debug_request(const mockfs_buf_in&, ssize_t buflen);
288 	void debug_response(const mockfs_buf_out&);
289 
290 	/* Initialize a session after mounting */
291 	void init(uint32_t flags);
292 
293 	/* Is pid from a process that might be involved in the test? */
294 	bool pid_ok(pid_t pid);
295 
296 	/* Default request handler */
297 	void process_default(const mockfs_buf_in&,
298 		std::vector<std::unique_ptr<mockfs_buf_out>>&);
299 
300 	/* Entry point for the daemon thread */
301 	static void* service(void*);
302 
303 	/*
304 	 * Read, but do not process, a single request from the kernel
305 	 *
306 	 * @param in	Return storage for the FUSE request
307 	 * @param res	Return value of read(2).  If positive, the amount of
308 	 *		data read from the fuse device.
309 	 */
310 	void read_request(mockfs_buf_in& in, ssize_t& res);
311 
312 	/* Write a single response back to the kernel */
313 	void write_response(const mockfs_buf_out &out);
314 
315 	public:
316 	/* pid of child process, for two-process test cases */
317 	pid_t m_child_pid;
318 
319 	/* Maximum size of a FUSE_WRITE write */
320 	uint32_t m_maxwrite;
321 
322 	/*
323 	 * Number of events that were available from /dev/fuse after the last
324 	 * kevent call.  Only valid when m_pm = KQ.
325 	 */
326 	int m_nready;
327 
328 	/* Tell the daemon to shut down ASAP */
329 	bool m_quit;
330 
331 	/* Create a new mockfs and mount it to a tempdir */
332 	MockFS(int max_readahead, bool allow_other,
333 		bool default_permissions, bool push_symlinks_in, bool ro,
334 		enum poll_method pm, uint32_t flags,
335 		uint32_t kernel_minor_version, uint32_t max_write, bool async,
336 		bool no_clusterr, unsigned time_gran, bool nointr);
337 
338 	virtual ~MockFS();
339 
340 	/* Kill the filesystem daemon without unmounting the filesystem */
341 	void kill_daemon();
342 
343 	/* Process FUSE requests endlessly */
344 	void loop();
345 
346 	/*
347 	 * Send an asynchronous notification to invalidate a directory entry.
348 	 * Similar to libfuse's fuse_lowlevel_notify_inval_entry
349 	 *
350 	 * This method will block until the client has responded, so it should
351 	 * generally be run in a separate thread from request processing.
352 	 *
353 	 * @param	parent	Parent directory's inode number
354 	 * @param	name	name of dirent to invalidate
355 	 * @param	namelen	size of name, including the NUL
356 	 */
357 	int notify_inval_entry(ino_t parent, const char *name, size_t namelen);
358 
359 	/*
360 	 * Send an asynchronous notification to invalidate an inode's cached
361 	 * data and/or attributes.  Similar to libfuse's
362 	 * fuse_lowlevel_notify_inval_inode.
363 	 *
364 	 * This method will block until the client has responded, so it should
365 	 * generally be run in a separate thread from request processing.
366 	 *
367 	 * @param	ino	File's inode number
368 	 * @param	off	offset at which to begin invalidation.  A
369 	 * 			negative offset means to invalidate attributes
370 	 * 			only.
371 	 * @param	len	Size of region of data to invalidate.  0 means
372 	 * 			to invalidate all cached data.
373 	 */
374 	int notify_inval_inode(ino_t ino, off_t off, ssize_t len);
375 
376 	/*
377 	 * Send an asynchronous notification to store data directly into an
378 	 * inode's cache.  Similar to libfuse's fuse_lowlevel_notify_store.
379 	 *
380 	 * This method will block until the client has responded, so it should
381 	 * generally be run in a separate thread from request processing.
382 	 *
383 	 * @param	ino	File's inode number
384 	 * @param	off	Offset at which to store data
385 	 * @param	data	Pointer to the data to cache
386 	 * @param	len	Size of data
387 	 */
388 	int notify_store(ino_t ino, off_t off, const void* data, ssize_t size);
389 
390 	/*
391 	 * Request handler
392 	 *
393 	 * This method is expected to provide the responses to each FUSE
394 	 * operation.  For an immediate response, push one buffer into out.
395 	 * For a delayed response, push nothing.  For an immediate response
396 	 * plus a delayed response to an earlier operation, push two bufs.
397 	 * Test cases must define each response using Googlemock expectations
398 	 */
399 	MOCK_METHOD2(process, void(const mockfs_buf_in&,
400 				std::vector<std::unique_ptr<mockfs_buf_out>>&));
401 
402 	/* Gracefully unmount */
403 	void unmount();
404 };
405