1 // SPDX-License-Identifier: GPL-2.0
5 * Setup and helper functions to access QDIO.
7 * Copyright IBM Corp. 2002, 2020
10 #define KMSG_COMPONENT "zfcp"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13 #include <linux/lockdep.h>
14 #include <linux/slab.h>
15 #include <linux/module.h>
17 #include "zfcp_qdio.h"
19 static bool enable_multibuffer
= true;
20 module_param_named(datarouter
, enable_multibuffer
, bool, 0400);
21 MODULE_PARM_DESC(datarouter
, "Enable hardware data router support (default on)");
23 #define ZFCP_QDIO_REQUEST_RESCAN_MSECS (MSEC_PER_SEC * 10)
24 #define ZFCP_QDIO_REQUEST_SCAN_MSECS MSEC_PER_SEC
26 static void zfcp_qdio_handler_error(struct zfcp_qdio
*qdio
, char *dbftag
,
27 unsigned int qdio_err
)
29 struct zfcp_adapter
*adapter
= qdio
->adapter
;
31 dev_warn(&adapter
->ccw_device
->dev
, "A QDIO problem occurred\n");
33 if (qdio_err
& QDIO_ERROR_SLSB_STATE
) {
34 zfcp_qdio_siosl(adapter
);
35 zfcp_erp_adapter_shutdown(adapter
, 0, dbftag
);
38 zfcp_erp_adapter_reopen(adapter
,
39 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED
|
40 ZFCP_STATUS_COMMON_ERP_FAILED
, dbftag
);
43 static void zfcp_qdio_zero_sbals(struct qdio_buffer
*sbal
[], int first
, int cnt
)
47 for (i
= first
; i
< first
+ cnt
; i
++) {
48 sbal_idx
= i
% QDIO_MAX_BUFFERS_PER_Q
;
49 memset(sbal
[sbal_idx
], 0, sizeof(struct qdio_buffer
));
53 /* this needs to be called prior to updating the queue fill level */
54 static inline void zfcp_qdio_account(struct zfcp_qdio
*qdio
)
56 unsigned long long now
, span
;
59 now
= get_tod_clock_monotonic();
60 span
= (now
- qdio
->req_q_time
) >> 12;
61 used
= QDIO_MAX_BUFFERS_PER_Q
- atomic_read(&qdio
->req_q_free
);
62 qdio
->req_q_util
+= used
* span
;
63 qdio
->req_q_time
= now
;
66 static void zfcp_qdio_int_req(struct ccw_device
*cdev
, unsigned int qdio_err
,
67 int queue_no
, int idx
, int count
,
70 struct zfcp_qdio
*qdio
= (struct zfcp_qdio
*) parm
;
72 zfcp_qdio_handler_error(qdio
, "qdireq1", qdio_err
);
75 static void zfcp_qdio_request_tasklet(struct tasklet_struct
*tasklet
)
77 struct zfcp_qdio
*qdio
= from_tasklet(qdio
, tasklet
, request_tasklet
);
78 struct ccw_device
*cdev
= qdio
->adapter
->ccw_device
;
79 unsigned int start
, error
;
82 completed
= qdio_inspect_output_queue(cdev
, 0, &start
, &error
);
85 zfcp_qdio_handler_error(qdio
, "qdreqt1", error
);
87 /* cleanup all SBALs being program-owned now */
88 zfcp_qdio_zero_sbals(qdio
->req_q
, start
, completed
);
90 spin_lock_irq(&qdio
->stat_lock
);
91 zfcp_qdio_account(qdio
);
92 spin_unlock_irq(&qdio
->stat_lock
);
93 atomic_add(completed
, &qdio
->req_q_free
);
94 wake_up(&qdio
->req_q_wq
);
98 if (atomic_read(&qdio
->req_q_free
) < QDIO_MAX_BUFFERS_PER_Q
)
99 timer_reduce(&qdio
->request_timer
,
100 jiffies
+ msecs_to_jiffies(ZFCP_QDIO_REQUEST_RESCAN_MSECS
));
103 static void zfcp_qdio_request_timer(struct timer_list
*timer
)
105 struct zfcp_qdio
*qdio
= from_timer(qdio
, timer
, request_timer
);
107 tasklet_schedule(&qdio
->request_tasklet
);
110 static void zfcp_qdio_int_resp(struct ccw_device
*cdev
, unsigned int qdio_err
,
111 int queue_no
, int idx
, int count
,
114 struct zfcp_qdio
*qdio
= (struct zfcp_qdio
*) parm
;
115 struct zfcp_adapter
*adapter
= qdio
->adapter
;
116 int sbal_no
, sbal_idx
;
118 if (unlikely(qdio_err
)) {
119 if (zfcp_adapter_multi_buffer_active(adapter
)) {
120 void *pl
[ZFCP_QDIO_MAX_SBALS_PER_REQ
+ 1];
121 struct qdio_buffer_element
*sbale
;
126 ZFCP_QDIO_MAX_SBALS_PER_REQ
* sizeof(void *));
127 sbale
= qdio
->res_q
[idx
]->element
;
128 req_id
= dma64_to_u64(sbale
->addr
);
129 scount
= min(sbale
->scount
+ 1,
130 ZFCP_QDIO_MAX_SBALS_PER_REQ
+ 1);
131 /* incl. signaling SBAL */
133 for (sbal_no
= 0; sbal_no
< scount
; sbal_no
++) {
134 sbal_idx
= (idx
+ sbal_no
) %
135 QDIO_MAX_BUFFERS_PER_Q
;
136 pl
[sbal_no
] = qdio
->res_q
[sbal_idx
];
138 zfcp_dbf_hba_def_err(adapter
, req_id
, scount
, pl
);
140 zfcp_qdio_handler_error(qdio
, "qdires1", qdio_err
);
145 * go through all SBALs from input queue currently
146 * returned by QDIO layer
148 for (sbal_no
= 0; sbal_no
< count
; sbal_no
++) {
149 sbal_idx
= (idx
+ sbal_no
) % QDIO_MAX_BUFFERS_PER_Q
;
150 /* go through all SBALEs of SBAL */
151 zfcp_fsf_reqid_check(qdio
, sbal_idx
);
155 * put SBALs back to response queue
157 if (qdio_add_bufs_to_input_queue(cdev
, 0, idx
, count
))
158 zfcp_erp_adapter_reopen(qdio
->adapter
, 0, "qdires2");
161 static void zfcp_qdio_irq_tasklet(struct tasklet_struct
*tasklet
)
163 struct zfcp_qdio
*qdio
= from_tasklet(qdio
, tasklet
, irq_tasklet
);
164 struct ccw_device
*cdev
= qdio
->adapter
->ccw_device
;
165 unsigned int start
, error
;
168 if (atomic_read(&qdio
->req_q_free
) < QDIO_MAX_BUFFERS_PER_Q
)
169 tasklet_schedule(&qdio
->request_tasklet
);
171 /* Check the Response Queue: */
172 completed
= qdio_inspect_input_queue(cdev
, 0, &start
, &error
);
176 zfcp_qdio_int_resp(cdev
, error
, 0, start
, completed
,
177 (unsigned long) qdio
);
179 if (qdio_start_irq(cdev
))
180 /* More work pending: */
181 tasklet_schedule(&qdio
->irq_tasklet
);
184 static void zfcp_qdio_poll(struct ccw_device
*cdev
, unsigned long data
)
186 struct zfcp_qdio
*qdio
= (struct zfcp_qdio
*) data
;
188 tasklet_schedule(&qdio
->irq_tasklet
);
191 static struct qdio_buffer_element
*
192 zfcp_qdio_sbal_chain(struct zfcp_qdio
*qdio
, struct zfcp_qdio_req
*q_req
)
194 struct qdio_buffer_element
*sbale
;
196 /* set last entry flag in current SBALE of current SBAL */
197 sbale
= zfcp_qdio_sbale_curr(qdio
, q_req
);
198 sbale
->eflags
|= SBAL_EFLAGS_LAST_ENTRY
;
200 /* don't exceed last allowed SBAL */
201 if (q_req
->sbal_last
== q_req
->sbal_limit
)
204 /* set chaining flag in first SBALE of current SBAL */
205 sbale
= zfcp_qdio_sbale_req(qdio
, q_req
);
206 sbale
->sflags
|= SBAL_SFLAGS0_MORE_SBALS
;
208 /* calculate index of next SBAL */
210 q_req
->sbal_last
%= QDIO_MAX_BUFFERS_PER_Q
;
212 /* keep this requests number of SBALs up-to-date */
213 q_req
->sbal_number
++;
214 BUG_ON(q_req
->sbal_number
> ZFCP_QDIO_MAX_SBALS_PER_REQ
);
216 /* start at first SBALE of new SBAL */
217 q_req
->sbale_curr
= 0;
219 /* set storage-block type for new SBAL */
220 sbale
= zfcp_qdio_sbale_curr(qdio
, q_req
);
221 sbale
->sflags
|= q_req
->sbtype
;
226 static struct qdio_buffer_element
*
227 zfcp_qdio_sbale_next(struct zfcp_qdio
*qdio
, struct zfcp_qdio_req
*q_req
)
229 if (q_req
->sbale_curr
== qdio
->max_sbale_per_sbal
- 1)
230 return zfcp_qdio_sbal_chain(qdio
, q_req
);
232 return zfcp_qdio_sbale_curr(qdio
, q_req
);
236 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
237 * @qdio: pointer to struct zfcp_qdio
238 * @q_req: pointer to struct zfcp_qdio_req
239 * @sg: scatter-gather list
240 * Returns: zero or -EINVAL on error
242 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio
*qdio
, struct zfcp_qdio_req
*q_req
,
243 struct scatterlist
*sg
)
245 struct qdio_buffer_element
*sbale
;
247 /* set storage-block type for this request */
248 sbale
= zfcp_qdio_sbale_req(qdio
, q_req
);
249 sbale
->sflags
|= q_req
->sbtype
;
251 for (; sg
; sg
= sg_next(sg
)) {
252 sbale
= zfcp_qdio_sbale_next(qdio
, q_req
);
254 atomic_inc(&qdio
->req_q_full
);
255 zfcp_qdio_zero_sbals(qdio
->req_q
, q_req
->sbal_first
,
259 sbale
->addr
= u64_to_dma64(sg_phys(sg
));
260 sbale
->length
= sg
->length
;
265 static int zfcp_qdio_sbal_check(struct zfcp_qdio
*qdio
)
267 if (atomic_read(&qdio
->req_q_free
) ||
268 !(atomic_read(&qdio
->adapter
->status
) & ZFCP_STATUS_ADAPTER_QDIOUP
))
274 * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary
275 * @qdio: pointer to struct zfcp_qdio
277 * The req_q_lock must be held by the caller of this function, and
278 * this function may only be called from process context; it will
279 * sleep when waiting for a free sbal.
281 * Returns: 0 on success, -EIO if there is no free sbal after waiting.
283 int zfcp_qdio_sbal_get(struct zfcp_qdio
*qdio
)
287 ret
= wait_event_interruptible_lock_irq_timeout(qdio
->req_q_wq
,
288 zfcp_qdio_sbal_check(qdio
), qdio
->req_q_lock
, 5 * HZ
);
290 if (!(atomic_read(&qdio
->adapter
->status
) & ZFCP_STATUS_ADAPTER_QDIOUP
))
297 atomic_inc(&qdio
->req_q_full
);
298 /* assume hanging outbound queue, try queue recovery */
299 zfcp_erp_adapter_reopen(qdio
->adapter
, 0, "qdsbg_1");
306 * zfcp_qdio_send - send req to QDIO
307 * @qdio: pointer to struct zfcp_qdio
308 * @q_req: pointer to struct zfcp_qdio_req
309 * Returns: 0 on success, error otherwise
311 int zfcp_qdio_send(struct zfcp_qdio
*qdio
, struct zfcp_qdio_req
*q_req
)
314 u8 sbal_number
= q_req
->sbal_number
;
317 * This should actually be a spin_lock_bh(stat_lock), to protect against
318 * Request Queue completion processing in tasklet context.
319 * But we can't do so (and are safe), as we always get called with IRQs
320 * disabled by spin_lock_irq[save](req_q_lock).
322 lockdep_assert_irqs_disabled();
323 spin_lock(&qdio
->stat_lock
);
324 zfcp_qdio_account(qdio
);
325 spin_unlock(&qdio
->stat_lock
);
327 atomic_sub(sbal_number
, &qdio
->req_q_free
);
329 retval
= qdio_add_bufs_to_output_queue(qdio
->adapter
->ccw_device
, 0,
330 q_req
->sbal_first
, sbal_number
,
333 if (unlikely(retval
)) {
334 /* Failed to submit the IO, roll back our modifications. */
335 atomic_add(sbal_number
, &qdio
->req_q_free
);
336 zfcp_qdio_zero_sbals(qdio
->req_q
, q_req
->sbal_first
,
341 if (atomic_read(&qdio
->req_q_free
) <= 2 * ZFCP_QDIO_MAX_SBALS_PER_REQ
)
342 tasklet_schedule(&qdio
->request_tasklet
);
344 timer_reduce(&qdio
->request_timer
,
345 jiffies
+ msecs_to_jiffies(ZFCP_QDIO_REQUEST_SCAN_MSECS
));
347 /* account for transferred buffers */
348 qdio
->req_q_idx
+= sbal_number
;
349 qdio
->req_q_idx
%= QDIO_MAX_BUFFERS_PER_Q
;
355 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
356 * @qdio: pointer to struct zfcp_qdio
357 * Returns: -ENOMEM on memory allocation error or return value from
360 static int zfcp_qdio_allocate(struct zfcp_qdio
*qdio
)
364 ret
= qdio_alloc_buffers(qdio
->req_q
, QDIO_MAX_BUFFERS_PER_Q
);
368 ret
= qdio_alloc_buffers(qdio
->res_q
, QDIO_MAX_BUFFERS_PER_Q
);
372 init_waitqueue_head(&qdio
->req_q_wq
);
374 ret
= qdio_allocate(qdio
->adapter
->ccw_device
, 1, 1);
381 qdio_free_buffers(qdio
->res_q
, QDIO_MAX_BUFFERS_PER_Q
);
383 qdio_free_buffers(qdio
->req_q
, QDIO_MAX_BUFFERS_PER_Q
);
388 * zfcp_qdio_close - close qdio queues for an adapter
389 * @qdio: pointer to structure zfcp_qdio
391 void zfcp_qdio_close(struct zfcp_qdio
*qdio
)
393 struct zfcp_adapter
*adapter
= qdio
->adapter
;
396 if (!(atomic_read(&adapter
->status
) & ZFCP_STATUS_ADAPTER_QDIOUP
))
400 * Clear QDIOUP flag, thus qdio_add_bufs_to_output_queue() is not called
401 * during qdio_shutdown().
403 spin_lock_irq(&qdio
->req_q_lock
);
404 atomic_andnot(ZFCP_STATUS_ADAPTER_QDIOUP
, &adapter
->status
);
405 spin_unlock_irq(&qdio
->req_q_lock
);
407 wake_up(&qdio
->req_q_wq
);
409 tasklet_disable(&qdio
->irq_tasklet
);
410 tasklet_disable(&qdio
->request_tasklet
);
411 del_timer_sync(&qdio
->request_timer
);
412 qdio_stop_irq(adapter
->ccw_device
);
413 qdio_shutdown(adapter
->ccw_device
, QDIO_FLAG_CLEANUP_USING_CLEAR
);
415 /* cleanup used outbound sbals */
416 count
= atomic_read(&qdio
->req_q_free
);
417 if (count
< QDIO_MAX_BUFFERS_PER_Q
) {
418 idx
= (qdio
->req_q_idx
+ count
) % QDIO_MAX_BUFFERS_PER_Q
;
419 count
= QDIO_MAX_BUFFERS_PER_Q
- count
;
420 zfcp_qdio_zero_sbals(qdio
->req_q
, idx
, count
);
423 atomic_set(&qdio
->req_q_free
, 0);
426 void zfcp_qdio_shost_update(struct zfcp_adapter
*const adapter
,
427 const struct zfcp_qdio
*const qdio
)
429 struct Scsi_Host
*const shost
= adapter
->scsi_host
;
434 shost
->sg_tablesize
= qdio
->max_sbale_per_req
;
435 shost
->max_sectors
= qdio
->max_sbale_per_req
* 8;
439 * zfcp_qdio_open - prepare and initialize response queue
440 * @qdio: pointer to struct zfcp_qdio
441 * Returns: 0 on success, otherwise -EIO
443 int zfcp_qdio_open(struct zfcp_qdio
*qdio
)
445 struct qdio_buffer
**input_sbals
[1] = {qdio
->res_q
};
446 struct qdio_buffer
**output_sbals
[1] = {qdio
->req_q
};
447 struct qdio_buffer_element
*sbale
;
448 struct qdio_initialize init_data
= {0};
449 struct zfcp_adapter
*adapter
= qdio
->adapter
;
450 struct ccw_device
*cdev
= adapter
->ccw_device
;
451 struct qdio_ssqd_desc ssqd
;
454 if (atomic_read(&adapter
->status
) & ZFCP_STATUS_ADAPTER_QDIOUP
)
457 atomic_andnot(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED
,
458 &qdio
->adapter
->status
);
460 init_data
.q_format
= QDIO_ZFCP_QFMT
;
461 init_data
.qib_rflags
= QIB_RFLAGS_ENABLE_DATA_DIV
;
462 if (enable_multibuffer
)
463 init_data
.qdr_ac
|= QDR_AC_MULTI_BUFFER_ENABLE
;
464 init_data
.no_input_qs
= 1;
465 init_data
.no_output_qs
= 1;
466 init_data
.input_handler
= zfcp_qdio_int_resp
;
467 init_data
.output_handler
= zfcp_qdio_int_req
;
468 init_data
.irq_poll
= zfcp_qdio_poll
;
469 init_data
.int_parm
= (unsigned long) qdio
;
470 init_data
.input_sbal_addr_array
= input_sbals
;
471 init_data
.output_sbal_addr_array
= output_sbals
;
473 if (qdio_establish(cdev
, &init_data
))
474 goto failed_establish
;
476 if (qdio_get_ssqd_desc(cdev
, &ssqd
))
479 if (ssqd
.qdioac2
& CHSC_AC2_DATA_DIV_ENABLED
)
480 atomic_or(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED
,
481 &qdio
->adapter
->status
);
483 if (ssqd
.qdioac2
& CHSC_AC2_MULTI_BUFFER_ENABLED
) {
484 atomic_or(ZFCP_STATUS_ADAPTER_MB_ACT
, &adapter
->status
);
485 qdio
->max_sbale_per_sbal
= QDIO_MAX_ELEMENTS_PER_BUFFER
;
487 atomic_andnot(ZFCP_STATUS_ADAPTER_MB_ACT
, &adapter
->status
);
488 qdio
->max_sbale_per_sbal
= QDIO_MAX_ELEMENTS_PER_BUFFER
- 1;
491 qdio
->max_sbale_per_req
=
492 ZFCP_QDIO_MAX_SBALS_PER_REQ
* qdio
->max_sbale_per_sbal
494 if (qdio_activate(cdev
))
497 for (cc
= 0; cc
< QDIO_MAX_BUFFERS_PER_Q
; cc
++) {
498 sbale
= &(qdio
->res_q
[cc
]->element
[0]);
500 sbale
->eflags
= SBAL_EFLAGS_LAST_ENTRY
;
505 if (qdio_add_bufs_to_input_queue(cdev
, 0, 0, QDIO_MAX_BUFFERS_PER_Q
))
508 /* set index of first available SBALS / number of available SBALS */
510 atomic_set(&qdio
->req_q_free
, QDIO_MAX_BUFFERS_PER_Q
);
511 atomic_or(ZFCP_STATUS_ADAPTER_QDIOUP
, &qdio
->adapter
->status
);
513 /* Enable processing for Request Queue completions: */
514 tasklet_enable(&qdio
->request_tasklet
);
515 /* Enable processing for QDIO interrupts: */
516 tasklet_enable(&qdio
->irq_tasklet
);
517 /* This results in a qdio_start_irq(): */
518 tasklet_schedule(&qdio
->irq_tasklet
);
520 zfcp_qdio_shost_update(adapter
, qdio
);
525 qdio_shutdown(cdev
, QDIO_FLAG_CLEANUP_USING_CLEAR
);
528 "Setting up the QDIO connection to the FCP adapter failed\n");
532 void zfcp_qdio_destroy(struct zfcp_qdio
*qdio
)
537 tasklet_kill(&qdio
->irq_tasklet
);
538 tasklet_kill(&qdio
->request_tasklet
);
540 if (qdio
->adapter
->ccw_device
)
541 qdio_free(qdio
->adapter
->ccw_device
);
543 qdio_free_buffers(qdio
->req_q
, QDIO_MAX_BUFFERS_PER_Q
);
544 qdio_free_buffers(qdio
->res_q
, QDIO_MAX_BUFFERS_PER_Q
);
548 int zfcp_qdio_setup(struct zfcp_adapter
*adapter
)
550 struct zfcp_qdio
*qdio
;
552 qdio
= kzalloc(sizeof(struct zfcp_qdio
), GFP_KERNEL
);
556 qdio
->adapter
= adapter
;
558 if (zfcp_qdio_allocate(qdio
)) {
563 spin_lock_init(&qdio
->req_q_lock
);
564 spin_lock_init(&qdio
->stat_lock
);
565 timer_setup(&qdio
->request_timer
, zfcp_qdio_request_timer
, 0);
566 tasklet_setup(&qdio
->irq_tasklet
, zfcp_qdio_irq_tasklet
);
567 tasklet_setup(&qdio
->request_tasklet
, zfcp_qdio_request_tasklet
);
568 tasklet_disable(&qdio
->irq_tasklet
);
569 tasklet_disable(&qdio
->request_tasklet
);
571 adapter
->qdio
= qdio
;
576 * zfcp_qdio_siosl - Trigger logging in FCP channel
577 * @adapter: The zfcp_adapter where to trigger logging
579 * Call the cio siosl function to trigger hardware logging. This
580 * wrapper function sets a flag to ensure hardware logging is only
581 * triggered once before going through qdio shutdown.
583 * The triggers are always run from qdio tasklet context, so no
584 * additional synchronization is necessary.
586 void zfcp_qdio_siosl(struct zfcp_adapter
*adapter
)
590 if (atomic_read(&adapter
->status
) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED
)
593 rc
= ccw_device_siosl(adapter
->ccw_device
);
595 atomic_or(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED
,