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1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright(c) 2019 Intel Corporation. All rights rsvd. */
3 #ifndef _IDXD_H_
4 #define _IDXD_H_
5 
6 #include <linux/sbitmap.h>
7 #include <linux/dmaengine.h>
8 #include <linux/percpu-rwsem.h>
9 #include <linux/wait.h>
10 #include <linux/cdev.h>
11 #include <linux/idr.h>
12 #include <linux/pci.h>
13 #include <linux/perf_event.h>
14 #include <uapi/linux/idxd.h>
15 #include "registers.h"
16 
17 #define IDXD_DRIVER_VERSION	"1.00"
18 
19 extern struct kmem_cache *idxd_desc_pool;
20 extern bool tc_override;
21 
22 struct idxd_wq;
23 struct idxd_dev;
24 
25 enum idxd_dev_type {
26 	IDXD_DEV_NONE = -1,
27 	IDXD_DEV_DSA = 0,
28 	IDXD_DEV_IAX,
29 	IDXD_DEV_WQ,
30 	IDXD_DEV_GROUP,
31 	IDXD_DEV_ENGINE,
32 	IDXD_DEV_CDEV,
33 	IDXD_DEV_MAX_TYPE,
34 };
35 
36 struct idxd_dev {
37 	struct device conf_dev;
38 	enum idxd_dev_type type;
39 };
40 
41 #define IDXD_REG_TIMEOUT	50
42 #define IDXD_DRAIN_TIMEOUT	5000
43 
44 enum idxd_type {
45 	IDXD_TYPE_UNKNOWN = -1,
46 	IDXD_TYPE_DSA = 0,
47 	IDXD_TYPE_IAX,
48 	IDXD_TYPE_MAX,
49 };
50 
51 #define IDXD_NAME_SIZE		128
52 #define IDXD_PMU_EVENT_MAX	64
53 
54 struct idxd_device_driver {
55 	const char *name;
56 	enum idxd_dev_type *type;
57 	int (*probe)(struct idxd_dev *idxd_dev);
58 	void (*remove)(struct idxd_dev *idxd_dev);
59 	struct device_driver drv;
60 };
61 
62 extern struct idxd_device_driver dsa_drv;
63 extern struct idxd_device_driver idxd_drv;
64 extern struct idxd_device_driver idxd_dmaengine_drv;
65 extern struct idxd_device_driver idxd_user_drv;
66 
67 struct idxd_irq_entry {
68 	struct idxd_device *idxd;
69 	int id;
70 	int vector;
71 	struct llist_head pending_llist;
72 	struct list_head work_list;
73 	/*
74 	 * Lock to protect access between irq thread process descriptor
75 	 * and irq thread processing error descriptor.
76 	 */
77 	spinlock_t list_lock;
78 };
79 
80 struct idxd_group {
81 	struct idxd_dev idxd_dev;
82 	struct idxd_device *idxd;
83 	struct grpcfg grpcfg;
84 	int id;
85 	int num_engines;
86 	int num_wqs;
87 	bool use_rdbuf_limit;
88 	u8 rdbufs_allowed;
89 	u8 rdbufs_reserved;
90 	int tc_a;
91 	int tc_b;
92 };
93 
94 struct idxd_pmu {
95 	struct idxd_device *idxd;
96 
97 	struct perf_event *event_list[IDXD_PMU_EVENT_MAX];
98 	int n_events;
99 
100 	DECLARE_BITMAP(used_mask, IDXD_PMU_EVENT_MAX);
101 
102 	struct pmu pmu;
103 	char name[IDXD_NAME_SIZE];
104 	int cpu;
105 
106 	int n_counters;
107 	int counter_width;
108 	int n_event_categories;
109 
110 	bool per_counter_caps_supported;
111 	unsigned long supported_event_categories;
112 
113 	unsigned long supported_filters;
114 	int n_filters;
115 
116 	struct hlist_node cpuhp_node;
117 };
118 
119 #define IDXD_MAX_PRIORITY	0xf
120 
121 enum idxd_wq_state {
122 	IDXD_WQ_DISABLED = 0,
123 	IDXD_WQ_ENABLED,
124 };
125 
126 enum idxd_wq_flag {
127 	WQ_FLAG_DEDICATED = 0,
128 	WQ_FLAG_BLOCK_ON_FAULT,
129 };
130 
131 enum idxd_wq_type {
132 	IDXD_WQT_NONE = 0,
133 	IDXD_WQT_KERNEL,
134 	IDXD_WQT_USER,
135 };
136 
137 struct idxd_cdev {
138 	struct idxd_wq *wq;
139 	struct cdev cdev;
140 	struct idxd_dev idxd_dev;
141 	int minor;
142 };
143 
144 #define IDXD_ALLOCATED_BATCH_SIZE	128U
145 #define WQ_NAME_SIZE   1024
146 #define WQ_TYPE_SIZE   10
147 
148 enum idxd_op_type {
149 	IDXD_OP_BLOCK = 0,
150 	IDXD_OP_NONBLOCK = 1,
151 };
152 
153 enum idxd_complete_type {
154 	IDXD_COMPLETE_NORMAL = 0,
155 	IDXD_COMPLETE_ABORT,
156 	IDXD_COMPLETE_DEV_FAIL,
157 };
158 
159 struct idxd_dma_chan {
160 	struct dma_chan chan;
161 	struct idxd_wq *wq;
162 };
163 
164 struct idxd_wq {
165 	void __iomem *portal;
166 	u32 portal_offset;
167 	struct percpu_ref wq_active;
168 	struct completion wq_dead;
169 	struct idxd_dev idxd_dev;
170 	struct idxd_cdev *idxd_cdev;
171 	struct wait_queue_head err_queue;
172 	struct idxd_device *idxd;
173 	int id;
174 	enum idxd_wq_type type;
175 	struct idxd_group *group;
176 	int client_count;
177 	struct mutex wq_lock;	/* mutex for workqueue */
178 	u32 size;
179 	u32 threshold;
180 	u32 priority;
181 	enum idxd_wq_state state;
182 	unsigned long flags;
183 	union wqcfg *wqcfg;
184 	struct dsa_hw_desc **hw_descs;
185 	int num_descs;
186 	union {
187 		struct dsa_completion_record *compls;
188 		struct iax_completion_record *iax_compls;
189 	};
190 	void *compls_raw;
191 	dma_addr_t compls_addr;
192 	dma_addr_t compls_addr_raw;
193 	int compls_size;
194 	struct idxd_desc **descs;
195 	struct sbitmap_queue sbq;
196 	struct idxd_dma_chan *idxd_chan;
197 	char name[WQ_NAME_SIZE + 1];
198 	u64 max_xfer_bytes;
199 	u32 max_batch_size;
200 	bool ats_dis;
201 };
202 
203 struct idxd_engine {
204 	struct idxd_dev idxd_dev;
205 	int id;
206 	struct idxd_group *group;
207 	struct idxd_device *idxd;
208 };
209 
210 /* shadow registers */
211 struct idxd_hw {
212 	u32 version;
213 	union gen_cap_reg gen_cap;
214 	union wq_cap_reg wq_cap;
215 	union group_cap_reg group_cap;
216 	union engine_cap_reg engine_cap;
217 	struct opcap opcap;
218 	u32 cmd_cap;
219 };
220 
221 enum idxd_device_state {
222 	IDXD_DEV_HALTED = -1,
223 	IDXD_DEV_DISABLED = 0,
224 	IDXD_DEV_ENABLED,
225 };
226 
227 enum idxd_device_flag {
228 	IDXD_FLAG_CONFIGURABLE = 0,
229 	IDXD_FLAG_CMD_RUNNING,
230 	IDXD_FLAG_PASID_ENABLED,
231 };
232 
233 struct idxd_dma_dev {
234 	struct idxd_device *idxd;
235 	struct dma_device dma;
236 };
237 
238 struct idxd_driver_data {
239 	const char *name_prefix;
240 	enum idxd_type type;
241 	struct device_type *dev_type;
242 	int compl_size;
243 	int align;
244 };
245 
246 struct idxd_device {
247 	struct idxd_dev idxd_dev;
248 	struct idxd_driver_data *data;
249 	struct list_head list;
250 	struct idxd_hw hw;
251 	enum idxd_device_state state;
252 	unsigned long flags;
253 	int id;
254 	int major;
255 	u32 cmd_status;
256 
257 	struct pci_dev *pdev;
258 	void __iomem *reg_base;
259 
260 	spinlock_t dev_lock;	/* spinlock for device */
261 	spinlock_t cmd_lock;	/* spinlock for device commands */
262 	struct completion *cmd_done;
263 	struct idxd_group **groups;
264 	struct idxd_wq **wqs;
265 	struct idxd_engine **engines;
266 
267 	struct iommu_sva *sva;
268 	unsigned int pasid;
269 
270 	int num_groups;
271 
272 	u32 msix_perm_offset;
273 	u32 wqcfg_offset;
274 	u32 grpcfg_offset;
275 	u32 perfmon_offset;
276 
277 	u64 max_xfer_bytes;
278 	u32 max_batch_size;
279 	int max_groups;
280 	int max_engines;
281 	int max_rdbufs;
282 	int max_wqs;
283 	int max_wq_size;
284 	int rdbuf_limit;
285 	int nr_rdbufs;		/* non-reserved read buffers */
286 	unsigned int wqcfg_size;
287 
288 	union sw_err_reg sw_err;
289 	wait_queue_head_t cmd_waitq;
290 	int num_wq_irqs;
291 	struct idxd_irq_entry *irq_entries;
292 
293 	struct idxd_dma_dev *idxd_dma;
294 	struct workqueue_struct *wq;
295 	struct work_struct work;
296 
297 	int *int_handles;
298 
299 	struct idxd_pmu *idxd_pmu;
300 };
301 
302 /* IDXD software descriptor */
303 struct idxd_desc {
304 	union {
305 		struct dsa_hw_desc *hw;
306 		struct iax_hw_desc *iax_hw;
307 	};
308 	dma_addr_t desc_dma;
309 	union {
310 		struct dsa_completion_record *completion;
311 		struct iax_completion_record *iax_completion;
312 	};
313 	dma_addr_t compl_dma;
314 	struct dma_async_tx_descriptor txd;
315 	struct llist_node llnode;
316 	struct list_head list;
317 	int id;
318 	int cpu;
319 	struct idxd_wq *wq;
320 };
321 
322 /*
323  * This is software defined error for the completion status. We overload the error code
324  * that will never appear in completion status and only SWERR register.
325  */
326 enum idxd_completion_status {
327 	IDXD_COMP_DESC_ABORT = 0xff,
328 };
329 
330 #define idxd_confdev(idxd) &idxd->idxd_dev.conf_dev
331 #define wq_confdev(wq) &wq->idxd_dev.conf_dev
332 #define engine_confdev(engine) &engine->idxd_dev.conf_dev
333 #define group_confdev(group) &group->idxd_dev.conf_dev
334 #define cdev_dev(cdev) &cdev->idxd_dev.conf_dev
335 
336 #define confdev_to_idxd_dev(dev) container_of(dev, struct idxd_dev, conf_dev)
337 #define idxd_dev_to_idxd(idxd_dev) container_of(idxd_dev, struct idxd_device, idxd_dev)
338 #define idxd_dev_to_wq(idxd_dev) container_of(idxd_dev, struct idxd_wq, idxd_dev)
339 
confdev_to_idxd(struct device * dev)340 static inline struct idxd_device *confdev_to_idxd(struct device *dev)
341 {
342 	struct idxd_dev *idxd_dev = confdev_to_idxd_dev(dev);
343 
344 	return idxd_dev_to_idxd(idxd_dev);
345 }
346 
confdev_to_wq(struct device * dev)347 static inline struct idxd_wq *confdev_to_wq(struct device *dev)
348 {
349 	struct idxd_dev *idxd_dev = confdev_to_idxd_dev(dev);
350 
351 	return idxd_dev_to_wq(idxd_dev);
352 }
353 
confdev_to_engine(struct device * dev)354 static inline struct idxd_engine *confdev_to_engine(struct device *dev)
355 {
356 	struct idxd_dev *idxd_dev = confdev_to_idxd_dev(dev);
357 
358 	return container_of(idxd_dev, struct idxd_engine, idxd_dev);
359 }
360 
confdev_to_group(struct device * dev)361 static inline struct idxd_group *confdev_to_group(struct device *dev)
362 {
363 	struct idxd_dev *idxd_dev = confdev_to_idxd_dev(dev);
364 
365 	return container_of(idxd_dev, struct idxd_group, idxd_dev);
366 }
367 
dev_to_cdev(struct device * dev)368 static inline struct idxd_cdev *dev_to_cdev(struct device *dev)
369 {
370 	struct idxd_dev *idxd_dev = confdev_to_idxd_dev(dev);
371 
372 	return container_of(idxd_dev, struct idxd_cdev, idxd_dev);
373 }
374 
idxd_dev_set_type(struct idxd_dev * idev,int type)375 static inline void idxd_dev_set_type(struct idxd_dev *idev, int type)
376 {
377 	if (type >= IDXD_DEV_MAX_TYPE) {
378 		idev->type = IDXD_DEV_NONE;
379 		return;
380 	}
381 
382 	idev->type = type;
383 }
384 
385 extern struct bus_type dsa_bus_type;
386 
387 extern bool support_enqcmd;
388 extern struct ida idxd_ida;
389 extern struct device_type dsa_device_type;
390 extern struct device_type iax_device_type;
391 extern struct device_type idxd_wq_device_type;
392 extern struct device_type idxd_engine_device_type;
393 extern struct device_type idxd_group_device_type;
394 
is_dsa_dev(struct idxd_dev * idxd_dev)395 static inline bool is_dsa_dev(struct idxd_dev *idxd_dev)
396 {
397 	return idxd_dev->type == IDXD_DEV_DSA;
398 }
399 
is_iax_dev(struct idxd_dev * idxd_dev)400 static inline bool is_iax_dev(struct idxd_dev *idxd_dev)
401 {
402 	return idxd_dev->type == IDXD_DEV_IAX;
403 }
404 
is_idxd_dev(struct idxd_dev * idxd_dev)405 static inline bool is_idxd_dev(struct idxd_dev *idxd_dev)
406 {
407 	return is_dsa_dev(idxd_dev) || is_iax_dev(idxd_dev);
408 }
409 
is_idxd_wq_dev(struct idxd_dev * idxd_dev)410 static inline bool is_idxd_wq_dev(struct idxd_dev *idxd_dev)
411 {
412 	return idxd_dev->type == IDXD_DEV_WQ;
413 }
414 
is_idxd_wq_dmaengine(struct idxd_wq * wq)415 static inline bool is_idxd_wq_dmaengine(struct idxd_wq *wq)
416 {
417 	if (wq->type == IDXD_WQT_KERNEL && strcmp(wq->name, "dmaengine") == 0)
418 		return true;
419 	return false;
420 }
421 
is_idxd_wq_user(struct idxd_wq * wq)422 static inline bool is_idxd_wq_user(struct idxd_wq *wq)
423 {
424 	return wq->type == IDXD_WQT_USER;
425 }
426 
is_idxd_wq_kernel(struct idxd_wq * wq)427 static inline bool is_idxd_wq_kernel(struct idxd_wq *wq)
428 {
429 	return wq->type == IDXD_WQT_KERNEL;
430 }
431 
wq_dedicated(struct idxd_wq * wq)432 static inline bool wq_dedicated(struct idxd_wq *wq)
433 {
434 	return test_bit(WQ_FLAG_DEDICATED, &wq->flags);
435 }
436 
wq_shared(struct idxd_wq * wq)437 static inline bool wq_shared(struct idxd_wq *wq)
438 {
439 	return !test_bit(WQ_FLAG_DEDICATED, &wq->flags);
440 }
441 
device_pasid_enabled(struct idxd_device * idxd)442 static inline bool device_pasid_enabled(struct idxd_device *idxd)
443 {
444 	return test_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags);
445 }
446 
device_swq_supported(struct idxd_device * idxd)447 static inline bool device_swq_supported(struct idxd_device *idxd)
448 {
449 	return (support_enqcmd && device_pasid_enabled(idxd));
450 }
451 
452 enum idxd_portal_prot {
453 	IDXD_PORTAL_UNLIMITED = 0,
454 	IDXD_PORTAL_LIMITED,
455 };
456 
457 enum idxd_interrupt_type {
458 	IDXD_IRQ_MSIX = 0,
459 	IDXD_IRQ_IMS,
460 };
461 
idxd_get_wq_portal_offset(enum idxd_portal_prot prot)462 static inline int idxd_get_wq_portal_offset(enum idxd_portal_prot prot)
463 {
464 	return prot * 0x1000;
465 }
466 
idxd_get_wq_portal_full_offset(int wq_id,enum idxd_portal_prot prot)467 static inline int idxd_get_wq_portal_full_offset(int wq_id,
468 						 enum idxd_portal_prot prot)
469 {
470 	return ((wq_id * 4) << PAGE_SHIFT) + idxd_get_wq_portal_offset(prot);
471 }
472 
473 #define IDXD_PORTAL_MASK	(PAGE_SIZE - 1)
474 
475 /*
476  * Even though this function can be accessed by multiple threads, it is safe to use.
477  * At worst the address gets used more than once before it gets incremented. We don't
478  * hit a threshold until iops becomes many million times a second. So the occasional
479  * reuse of the same address is tolerable compare to using an atomic variable. This is
480  * safe on a system that has atomic load/store for 32bit integers. Given that this is an
481  * Intel iEP device, that should not be a problem.
482  */
idxd_wq_portal_addr(struct idxd_wq * wq)483 static inline void __iomem *idxd_wq_portal_addr(struct idxd_wq *wq)
484 {
485 	int ofs = wq->portal_offset;
486 
487 	wq->portal_offset = (ofs + sizeof(struct dsa_raw_desc)) & IDXD_PORTAL_MASK;
488 	return wq->portal + ofs;
489 }
490 
idxd_wq_get(struct idxd_wq * wq)491 static inline void idxd_wq_get(struct idxd_wq *wq)
492 {
493 	wq->client_count++;
494 }
495 
idxd_wq_put(struct idxd_wq * wq)496 static inline void idxd_wq_put(struct idxd_wq *wq)
497 {
498 	wq->client_count--;
499 }
500 
idxd_wq_refcount(struct idxd_wq * wq)501 static inline int idxd_wq_refcount(struct idxd_wq *wq)
502 {
503 	return wq->client_count;
504 };
505 
506 int __must_check __idxd_driver_register(struct idxd_device_driver *idxd_drv,
507 					struct module *module, const char *mod_name);
508 #define idxd_driver_register(driver) \
509 	__idxd_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
510 
511 void idxd_driver_unregister(struct idxd_device_driver *idxd_drv);
512 
513 #define module_idxd_driver(__idxd_driver) \
514 	module_driver(__idxd_driver, idxd_driver_register, idxd_driver_unregister)
515 
516 int idxd_register_bus_type(void);
517 void idxd_unregister_bus_type(void);
518 int idxd_register_devices(struct idxd_device *idxd);
519 void idxd_unregister_devices(struct idxd_device *idxd);
520 int idxd_register_driver(void);
521 void idxd_unregister_driver(void);
522 void idxd_wqs_quiesce(struct idxd_device *idxd);
523 
524 /* device interrupt control */
525 void idxd_msix_perm_setup(struct idxd_device *idxd);
526 void idxd_msix_perm_clear(struct idxd_device *idxd);
527 irqreturn_t idxd_misc_thread(int vec, void *data);
528 irqreturn_t idxd_wq_thread(int irq, void *data);
529 void idxd_mask_error_interrupts(struct idxd_device *idxd);
530 void idxd_unmask_error_interrupts(struct idxd_device *idxd);
531 void idxd_mask_msix_vectors(struct idxd_device *idxd);
532 void idxd_mask_msix_vector(struct idxd_device *idxd, int vec_id);
533 void idxd_unmask_msix_vector(struct idxd_device *idxd, int vec_id);
534 
535 /* device control */
536 int idxd_register_idxd_drv(void);
537 void idxd_unregister_idxd_drv(void);
538 int idxd_device_drv_probe(struct idxd_dev *idxd_dev);
539 void idxd_device_drv_remove(struct idxd_dev *idxd_dev);
540 int drv_enable_wq(struct idxd_wq *wq);
541 int __drv_enable_wq(struct idxd_wq *wq);
542 void drv_disable_wq(struct idxd_wq *wq);
543 void __drv_disable_wq(struct idxd_wq *wq);
544 int idxd_device_init_reset(struct idxd_device *idxd);
545 int idxd_device_enable(struct idxd_device *idxd);
546 int idxd_device_disable(struct idxd_device *idxd);
547 void idxd_device_reset(struct idxd_device *idxd);
548 void idxd_device_clear_state(struct idxd_device *idxd);
549 int idxd_device_config(struct idxd_device *idxd);
550 void idxd_device_drain_pasid(struct idxd_device *idxd, int pasid);
551 int idxd_device_load_config(struct idxd_device *idxd);
552 int idxd_device_request_int_handle(struct idxd_device *idxd, int idx, int *handle,
553 				   enum idxd_interrupt_type irq_type);
554 int idxd_device_release_int_handle(struct idxd_device *idxd, int handle,
555 				   enum idxd_interrupt_type irq_type);
556 
557 /* work queue control */
558 void idxd_wqs_unmap_portal(struct idxd_device *idxd);
559 int idxd_wq_alloc_resources(struct idxd_wq *wq);
560 void idxd_wq_free_resources(struct idxd_wq *wq);
561 int idxd_wq_enable(struct idxd_wq *wq);
562 int idxd_wq_disable(struct idxd_wq *wq, bool reset_config);
563 void idxd_wq_drain(struct idxd_wq *wq);
564 void idxd_wq_reset(struct idxd_wq *wq);
565 int idxd_wq_map_portal(struct idxd_wq *wq);
566 void idxd_wq_unmap_portal(struct idxd_wq *wq);
567 int idxd_wq_set_pasid(struct idxd_wq *wq, int pasid);
568 int idxd_wq_disable_pasid(struct idxd_wq *wq);
569 void idxd_wq_quiesce(struct idxd_wq *wq);
570 int idxd_wq_init_percpu_ref(struct idxd_wq *wq);
571 
572 /* submission */
573 int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc);
574 struct idxd_desc *idxd_alloc_desc(struct idxd_wq *wq, enum idxd_op_type optype);
575 void idxd_free_desc(struct idxd_wq *wq, struct idxd_desc *desc);
576 
577 /* dmaengine */
578 int idxd_register_dma_device(struct idxd_device *idxd);
579 void idxd_unregister_dma_device(struct idxd_device *idxd);
580 int idxd_register_dma_channel(struct idxd_wq *wq);
581 void idxd_unregister_dma_channel(struct idxd_wq *wq);
582 void idxd_parse_completion_status(u8 status, enum dmaengine_tx_result *res);
583 void idxd_dma_complete_txd(struct idxd_desc *desc,
584 			   enum idxd_complete_type comp_type);
585 
586 /* cdev */
587 int idxd_cdev_register(void);
588 void idxd_cdev_remove(void);
589 int idxd_cdev_get_major(struct idxd_device *idxd);
590 int idxd_wq_add_cdev(struct idxd_wq *wq);
591 void idxd_wq_del_cdev(struct idxd_wq *wq);
592 
593 /* perfmon */
594 #if IS_ENABLED(CONFIG_INTEL_IDXD_PERFMON)
595 int perfmon_pmu_init(struct idxd_device *idxd);
596 void perfmon_pmu_remove(struct idxd_device *idxd);
597 void perfmon_counter_overflow(struct idxd_device *idxd);
598 void perfmon_init(void);
599 void perfmon_exit(void);
600 #else
perfmon_pmu_init(struct idxd_device * idxd)601 static inline int perfmon_pmu_init(struct idxd_device *idxd) { return 0; }
perfmon_pmu_remove(struct idxd_device * idxd)602 static inline void perfmon_pmu_remove(struct idxd_device *idxd) {}
perfmon_counter_overflow(struct idxd_device * idxd)603 static inline void perfmon_counter_overflow(struct idxd_device *idxd) {}
perfmon_init(void)604 static inline void perfmon_init(void) {}
perfmon_exit(void)605 static inline void perfmon_exit(void) {}
606 #endif
607 
complete_desc(struct idxd_desc * desc,enum idxd_complete_type reason)608 static inline void complete_desc(struct idxd_desc *desc, enum idxd_complete_type reason)
609 {
610 	idxd_dma_complete_txd(desc, reason);
611 	idxd_free_desc(desc->wq, desc);
612 }
613 
614 #endif
615