6 #include "flush.h"
29 	/* The current flush generation of the vdo */
31 	/* The first unacknowledged flush generation */
33 	/* The queue of flush requests waiting to notify other threads */
35 	/* The queue of flush requests waiting for VIOs to complete */
37 	/* The flush generation for which notifications are being sent */
41 	/* The ID of the thread on which flush requests should be made */
43 	/* The pool of flush requests */
45 	/* Bios waiting for a flush request to become available */
49 	/* The rotor for selecting the bio queue for submitting flush bios */
103 	struct vdo_flush *flush = NULL;  in allocate_flush()  local
106 		flush = vdo_allocate_memory_nowait(sizeof(struct vdo_flush), __func__);  in allocate_flush()
108 		int result = vdo_allocate(1, struct vdo_flush, __func__, &flush);  in allocate_flush()
111 			vdo_log_error_strerror(result, "failed to allocate spare flush");  in allocate_flush()
114 	if (flush != NULL) {  in allocate_flush()
117 		vdo_initialize_completion(&flush->completion, flusher->vdo,  in allocate_flush()
121 	return flush;  in allocate_flush()
182 static void vdo_complete_flush(struct vdo_flush *flush);
189  * the notification of the next flush request if one came in while the current notification was in
206  * flush_packer_callback() - Flush the packer.
210  * flush request. This callback is registered in increment_generation().
222  * increment_generation() - Increment the flush generation in a logical zone.
246  * notify_flush() - Launch a flush notification.
251 	struct vdo_flush *flush =  in notify_flush()  local
254 	flusher->notify_generation = flush->flush_generation;  in notify_flush()
262  * flush_vdo() - Start processing a flush request.
263  * @completion: A flush request (as a vdo_completion)
269 	struct vdo_flush *flush = completion_as_vdo_flush(completion);  in flush_vdo()  local
279 		vdo_complete_flush(flush);  in flush_vdo()
283 	flush->flush_generation = flusher->flush_generation++;  in flush_vdo()
285 	vdo_waitq_enqueue_waiter(&flusher->notifiers, &flush->waiter);  in flush_vdo()
327 		struct vdo_flush *flush =  in vdo_complete_flushes()  local
330 		if (flush->flush_generation >= oldest_active_generation)  in vdo_complete_flushes()
333 		VDO_ASSERT_LOG_ONLY((flush->flush_generation ==  in vdo_complete_flushes()
335 				    "acknowledged next expected flush, %llu, was: %llu",  in vdo_complete_flushes()
337 				    (unsigned long long) flush->flush_generation);  in vdo_complete_flushes()
339 		vdo_complete_flush(flush);  in vdo_complete_flushes()
363  * @flush: The flush to initialize.
369 static void initialize_flush(struct vdo_flush *flush, struct vdo *vdo)  in initialize_flush()  argument
371 	bio_list_init(&flush->bios);  in initialize_flush()
372 	bio_list_merge_init(&flush->bios, &vdo->flusher->waiting_flush_bios);  in initialize_flush()
375 static void launch_flush(struct vdo_flush *flush)  in launch_flush()  argument
377 	struct vdo_completion *completion = &flush->completion;  in launch_flush()
385  * vdo_launch_flush() - Function called to start processing a flush request.
387  * @bio: The bio containing an empty flush request.
389  * This is called when we receive an empty flush bio from the block layer, and before acknowledging
395 	 * Try to allocate a vdo_flush to represent the flush request. If the allocation fails,  in vdo_launch_flush()
398 	struct vdo_flush *flush = mempool_alloc(vdo->flusher->flush_pool, GFP_NOWAIT);  in vdo_launch_flush()  local
410 	if (flush == NULL) {  in vdo_launch_flush()
416 	initialize_flush(flush, vdo);  in vdo_launch_flush()
420 	launch_flush(flush);  in vdo_launch_flush()
425  * @flush: The completed flush structure to re-use or free.
427  * If there are any pending flush requests whose vdo_flush allocation failed, they will be launched
431 static void release_flush(struct vdo_flush *flush)  in release_flush()  argument
434 	struct flusher *flusher = flush->completion.vdo->flusher;  in release_flush()
440 		/* We have flushes to start. Capture them in a flush request. */  in release_flush()
441 		initialize_flush(flush, flusher->vdo);  in release_flush()
448 		launch_flush(flush);  in release_flush()
452 	mempool_free(flush, flusher->flush_pool);  in release_flush()
456  * vdo_complete_flush_callback() - Function called to complete and free a flush request, registered
458  * @completion: The flush request.
462 	struct vdo_flush *flush = completion_as_vdo_flush(completion);  in vdo_complete_flush_callback()  local
466 	while ((bio = bio_list_pop(&flush->bios)) != NULL) {  in vdo_complete_flush_callback()
481 	 * Release the flush structure, freeing it, re-using it as the spare, or using it to launch  in vdo_complete_flush_callback()
484 	release_flush(flush);  in vdo_complete_flush_callback()
488  * select_bio_queue() - Select the bio queue on which to finish a flush request.
512  * vdo_complete_flush() - Complete and free a vdo flush request.
513  * @flush: The flush request.
515 static void vdo_complete_flush(struct vdo_flush *flush)  in vdo_complete_flush()  argument
517 	struct vdo_completion *completion = &flush->completion;  in vdo_complete_flush()