]>
Commit | Line | Data |
---|---|---|
7c673cae FG |
1 | // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- |
2 | // vim: ts=8 sw=2 smarttab | |
3 | ||
4 | #include "librbd/ExclusiveLock.h" | |
31f18b77 | 5 | #include "librbd/ImageCtx.h" |
7c673cae FG |
6 | #include "librbd/ImageWatcher.h" |
7 | #include "librbd/ImageState.h" | |
8 | #include "librbd/exclusive_lock/PreAcquireRequest.h" | |
9 | #include "librbd/exclusive_lock/PostAcquireRequest.h" | |
10 | #include "librbd/exclusive_lock/PreReleaseRequest.h" | |
11 | #include "librbd/io/ImageRequestWQ.h" | |
12 | #include "librbd/Utils.h" | |
13 | #include "common/Mutex.h" | |
14 | #include "common/dout.h" | |
15 | ||
16 | #define dout_subsys ceph_subsys_rbd | |
17 | #undef dout_prefix | |
18 | #define dout_prefix *_dout << "librbd::ExclusiveLock: " << this << " " \ | |
19 | << __func__ | |
20 | ||
21 | namespace librbd { | |
22 | ||
23 | using namespace exclusive_lock; | |
24 | ||
25 | template <typename I> | |
26 | using ML = ManagedLock<I>; | |
27 | ||
28 | template <typename I> | |
29 | ExclusiveLock<I>::ExclusiveLock(I &image_ctx) | |
30 | : ML<I>(image_ctx.md_ctx, image_ctx.op_work_queue, image_ctx.header_oid, | |
31 | image_ctx.image_watcher, managed_lock::EXCLUSIVE, | |
32 | image_ctx.blacklist_on_break_lock, | |
33 | image_ctx.blacklist_expire_seconds), | |
34 | m_image_ctx(image_ctx) { | |
35 | Mutex::Locker locker(ML<I>::m_lock); | |
36 | ML<I>::set_state_uninitialized(); | |
37 | } | |
38 | ||
39 | template <typename I> | |
40 | bool ExclusiveLock<I>::accept_requests(int *ret_val) const { | |
41 | Mutex::Locker locker(ML<I>::m_lock); | |
42 | ||
43 | bool accept_requests = (!ML<I>::is_state_shutdown() && | |
44 | ML<I>::is_state_locked() && | |
45 | m_request_blocked_count == 0); | |
31f18b77 FG |
46 | if (ret_val != nullptr) { |
47 | *ret_val = m_request_blocked_ret_val; | |
48 | } | |
7c673cae FG |
49 | |
50 | ldout(m_image_ctx.cct, 20) << "=" << accept_requests << dendl; | |
51 | return accept_requests; | |
52 | } | |
53 | ||
31f18b77 FG |
54 | template <typename I> |
55 | bool ExclusiveLock<I>::accept_ops() const { | |
56 | Mutex::Locker locker(ML<I>::m_lock); | |
57 | bool accept = accept_ops(ML<I>::m_lock); | |
58 | ldout(m_image_ctx.cct, 20) << "=" << accept << dendl; | |
59 | return accept; | |
60 | } | |
61 | ||
62 | template <typename I> | |
63 | bool ExclusiveLock<I>::accept_ops(const Mutex &lock) const { | |
64 | return (!ML<I>::is_state_shutdown() && | |
65 | (ML<I>::is_state_locked() || ML<I>::is_state_post_acquiring())); | |
66 | } | |
67 | ||
7c673cae FG |
68 | template <typename I> |
69 | void ExclusiveLock<I>::block_requests(int r) { | |
70 | Mutex::Locker locker(ML<I>::m_lock); | |
71 | ||
72 | m_request_blocked_count++; | |
73 | if (m_request_blocked_ret_val == 0) { | |
74 | m_request_blocked_ret_val = r; | |
75 | } | |
76 | ||
77 | ldout(m_image_ctx.cct, 20) << dendl; | |
78 | } | |
79 | ||
80 | template <typename I> | |
81 | void ExclusiveLock<I>::unblock_requests() { | |
82 | Mutex::Locker locker(ML<I>::m_lock); | |
83 | ||
84 | assert(m_request_blocked_count > 0); | |
85 | m_request_blocked_count--; | |
86 | if (m_request_blocked_count == 0) { | |
87 | m_request_blocked_ret_val = 0; | |
88 | } | |
89 | ||
90 | ldout(m_image_ctx.cct, 20) << dendl; | |
91 | } | |
92 | ||
93 | template <typename I> | |
94 | void ExclusiveLock<I>::init(uint64_t features, Context *on_init) { | |
95 | assert(m_image_ctx.owner_lock.is_locked()); | |
96 | ldout(m_image_ctx.cct, 10) << dendl; | |
97 | ||
98 | { | |
99 | Mutex::Locker locker(ML<I>::m_lock); | |
100 | ML<I>::set_state_initializing(); | |
101 | } | |
102 | ||
103 | m_image_ctx.io_work_queue->block_writes(new C_InitComplete(this, features, | |
104 | on_init)); | |
105 | } | |
106 | ||
107 | template <typename I> | |
108 | void ExclusiveLock<I>::shut_down(Context *on_shut_down) { | |
109 | ldout(m_image_ctx.cct, 10) << dendl; | |
110 | ||
111 | ML<I>::shut_down(on_shut_down); | |
112 | ||
113 | // if stalled in request state machine -- abort | |
114 | handle_peer_notification(0); | |
115 | } | |
116 | ||
117 | template <typename I> | |
118 | void ExclusiveLock<I>::handle_peer_notification(int r) { | |
119 | Mutex::Locker locker(ML<I>::m_lock); | |
120 | if (!ML<I>::is_state_waiting_for_lock()) { | |
121 | return; | |
122 | } | |
123 | ||
124 | ldout(m_image_ctx.cct, 10) << dendl; | |
125 | assert(ML<I>::is_action_acquire_lock()); | |
126 | ||
127 | m_acquire_lock_peer_ret_val = r; | |
128 | ML<I>::execute_next_action(); | |
129 | } | |
130 | ||
31f18b77 FG |
131 | template <typename I> |
132 | Context *ExclusiveLock<I>::start_op() { | |
133 | assert(m_image_ctx.owner_lock.is_locked()); | |
134 | Mutex::Locker locker(ML<I>::m_lock); | |
135 | ||
136 | if (!accept_ops(ML<I>::m_lock)) { | |
137 | return nullptr; | |
138 | } | |
139 | ||
140 | m_async_op_tracker.start_op(); | |
141 | return new FunctionContext([this](int r) { | |
142 | m_async_op_tracker.finish_op(); | |
143 | }); | |
144 | } | |
145 | ||
7c673cae FG |
146 | template <typename I> |
147 | void ExclusiveLock<I>::handle_init_complete(uint64_t features) { | |
31f18b77 | 148 | ldout(m_image_ctx.cct, 10) << ": features=" << features << dendl; |
7c673cae FG |
149 | |
150 | if ((features & RBD_FEATURE_JOURNALING) != 0) { | |
151 | m_image_ctx.io_work_queue->set_require_lock_on_read(); | |
152 | } | |
153 | ||
154 | Mutex::Locker locker(ML<I>::m_lock); | |
155 | ML<I>::set_state_unlocked(); | |
156 | } | |
157 | ||
158 | template <typename I> | |
159 | void ExclusiveLock<I>::shutdown_handler(int r, Context *on_finish) { | |
160 | ldout(m_image_ctx.cct, 10) << dendl; | |
161 | ||
162 | { | |
163 | RWLock::WLocker owner_locker(m_image_ctx.owner_lock); | |
164 | m_image_ctx.io_work_queue->clear_require_lock_on_read(); | |
165 | m_image_ctx.exclusive_lock = nullptr; | |
166 | } | |
167 | ||
168 | m_image_ctx.io_work_queue->unblock_writes(); | |
169 | m_image_ctx.image_watcher->flush(on_finish); | |
170 | } | |
171 | ||
172 | template <typename I> | |
173 | void ExclusiveLock<I>::pre_acquire_lock_handler(Context *on_finish) { | |
174 | ldout(m_image_ctx.cct, 10) << dendl; | |
175 | ||
176 | int acquire_lock_peer_ret_val = 0; | |
177 | { | |
178 | Mutex::Locker locker(ML<I>::m_lock); | |
179 | std::swap(acquire_lock_peer_ret_val, m_acquire_lock_peer_ret_val); | |
180 | } | |
181 | ||
182 | if (acquire_lock_peer_ret_val == -EROFS) { | |
183 | ldout(m_image_ctx.cct, 10) << ": peer nacked lock request" << dendl; | |
184 | on_finish->complete(acquire_lock_peer_ret_val); | |
185 | return; | |
186 | } | |
187 | ||
188 | PreAcquireRequest<I> *req = PreAcquireRequest<I>::create(m_image_ctx, | |
189 | on_finish); | |
190 | m_image_ctx.op_work_queue->queue(new FunctionContext([req](int r) { | |
191 | req->send(); | |
192 | })); | |
193 | } | |
194 | ||
195 | template <typename I> | |
196 | void ExclusiveLock<I>::post_acquire_lock_handler(int r, Context *on_finish) { | |
197 | ldout(m_image_ctx.cct, 10) << ": r=" << r << dendl; | |
198 | ||
199 | if (r == -EROFS) { | |
200 | // peer refused to release the exclusive lock | |
201 | on_finish->complete(r); | |
202 | return; | |
203 | } else if (r < 0) { | |
204 | ML<I>::m_lock.Lock(); | |
205 | assert(ML<I>::is_state_acquiring()); | |
206 | ||
207 | // PostAcquire state machine will not run, so we need complete prepare | |
208 | m_image_ctx.state->handle_prepare_lock_complete(); | |
209 | ||
210 | // if lock is in-use by another client, request the lock | |
211 | if (ML<I>::is_action_acquire_lock() && (r == -EBUSY || r == -EAGAIN)) { | |
212 | ML<I>::set_state_waiting_for_lock(); | |
213 | ML<I>::m_lock.Unlock(); | |
214 | ||
215 | // request the lock from a peer | |
216 | m_image_ctx.image_watcher->notify_request_lock(); | |
217 | ||
218 | // inform manage lock that we have interrupted the state machine | |
219 | r = -ECANCELED; | |
220 | } else { | |
221 | ML<I>::m_lock.Unlock(); | |
222 | ||
223 | // clear error if peer owns lock | |
224 | if (r == -EAGAIN) { | |
225 | r = 0; | |
226 | } | |
227 | } | |
228 | ||
229 | on_finish->complete(r); | |
230 | return; | |
231 | } | |
232 | ||
233 | Mutex::Locker locker(ML<I>::m_lock); | |
234 | m_pre_post_callback = on_finish; | |
235 | using EL = ExclusiveLock<I>; | |
236 | PostAcquireRequest<I> *req = PostAcquireRequest<I>::create(m_image_ctx, | |
237 | util::create_context_callback<EL, &EL::handle_post_acquiring_lock>(this), | |
238 | util::create_context_callback<EL, &EL::handle_post_acquired_lock>(this)); | |
239 | ||
240 | m_image_ctx.op_work_queue->queue(new FunctionContext([req](int r) { | |
241 | req->send(); | |
242 | })); | |
243 | } | |
244 | ||
245 | template <typename I> | |
246 | void ExclusiveLock<I>::handle_post_acquiring_lock(int r) { | |
247 | ldout(m_image_ctx.cct, 10) << dendl; | |
248 | ||
249 | Mutex::Locker locker(ML<I>::m_lock); | |
250 | ||
251 | assert(r == 0); | |
252 | ||
253 | // lock is owned at this point | |
254 | ML<I>::set_state_post_acquiring(); | |
255 | } | |
256 | ||
257 | template <typename I> | |
258 | void ExclusiveLock<I>::handle_post_acquired_lock(int r) { | |
259 | ldout(m_image_ctx.cct, 10) << ": r=" << r << dendl; | |
260 | ||
261 | Context *on_finish = nullptr; | |
262 | { | |
263 | Mutex::Locker locker(ML<I>::m_lock); | |
264 | assert(ML<I>::is_state_acquiring() || ML<I>::is_state_post_acquiring()); | |
265 | ||
266 | assert (m_pre_post_callback != nullptr); | |
267 | std::swap(m_pre_post_callback, on_finish); | |
268 | } | |
269 | ||
270 | if (r >= 0) { | |
271 | m_image_ctx.image_watcher->notify_acquired_lock(); | |
272 | m_image_ctx.io_work_queue->clear_require_lock_on_read(); | |
273 | m_image_ctx.io_work_queue->unblock_writes(); | |
274 | } | |
275 | ||
276 | on_finish->complete(r); | |
277 | } | |
278 | ||
279 | template <typename I> | |
280 | void ExclusiveLock<I>::pre_release_lock_handler(bool shutting_down, | |
281 | Context *on_finish) { | |
282 | ldout(m_image_ctx.cct, 10) << dendl; | |
283 | Mutex::Locker locker(ML<I>::m_lock); | |
284 | ||
285 | PreReleaseRequest<I> *req = PreReleaseRequest<I>::create( | |
31f18b77 | 286 | m_image_ctx, shutting_down, m_async_op_tracker, on_finish); |
7c673cae FG |
287 | m_image_ctx.op_work_queue->queue(new FunctionContext([req](int r) { |
288 | req->send(); | |
289 | })); | |
290 | } | |
291 | ||
292 | template <typename I> | |
293 | void ExclusiveLock<I>::post_release_lock_handler(bool shutting_down, int r, | |
294 | Context *on_finish) { | |
295 | ldout(m_image_ctx.cct, 10) << ": r=" << r << " shutting_down=" | |
296 | << shutting_down << dendl; | |
297 | if (!shutting_down) { | |
298 | { | |
299 | Mutex::Locker locker(ML<I>::m_lock); | |
300 | assert(ML<I>::is_state_pre_releasing() || ML<I>::is_state_releasing()); | |
301 | } | |
302 | ||
303 | if (r >= 0) { | |
304 | m_image_ctx.image_watcher->notify_released_lock(); | |
305 | if (m_image_ctx.io_work_queue->is_lock_request_needed()) { | |
306 | // if we have blocked IO -- re-request the lock | |
307 | RWLock::RLocker owner_locker(m_image_ctx.owner_lock); | |
308 | ML<I>::acquire_lock(nullptr); | |
309 | } | |
310 | } | |
311 | } else { | |
312 | { | |
313 | RWLock::WLocker owner_locker(m_image_ctx.owner_lock); | |
314 | m_image_ctx.io_work_queue->clear_require_lock_on_read(); | |
315 | m_image_ctx.exclusive_lock = nullptr; | |
316 | } | |
317 | ||
318 | if (r >= 0) { | |
319 | m_image_ctx.io_work_queue->unblock_writes(); | |
320 | } | |
321 | ||
322 | m_image_ctx.image_watcher->notify_released_lock(); | |
323 | } | |
324 | ||
325 | on_finish->complete(r); | |
326 | } | |
327 | ||
31f18b77 FG |
328 | template <typename I> |
329 | void ExclusiveLock<I>::post_reacquire_lock_handler(int r, Context *on_finish) { | |
330 | ldout(m_image_ctx.cct, 10) << dendl; | |
331 | if (r >= 0) { | |
332 | m_image_ctx.image_watcher->notify_acquired_lock(); | |
333 | } | |
334 | ||
335 | on_finish->complete(r); | |
336 | } | |
337 | ||
7c673cae FG |
338 | template <typename I> |
339 | struct ExclusiveLock<I>::C_InitComplete : public Context { | |
340 | ExclusiveLock *exclusive_lock; | |
341 | uint64_t features; | |
342 | Context *on_init; | |
343 | ||
344 | C_InitComplete(ExclusiveLock *exclusive_lock, uint64_t features, | |
345 | Context *on_init) | |
346 | : exclusive_lock(exclusive_lock), features(features), on_init(on_init) { | |
347 | } | |
348 | void finish(int r) override { | |
349 | if (r == 0) { | |
350 | exclusive_lock->handle_init_complete(features); | |
351 | } | |
352 | on_init->complete(r); | |
353 | } | |
354 | }; | |
355 | ||
356 | } // namespace librbd | |
357 | ||
358 | template class librbd::ExclusiveLock<librbd::ImageCtx>; |