2 * drivers/s390/cio/chsc.c
3 * S/390 common I/O routines -- channel subsystem call
6 * Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
8 * Author(s): Ingo Adlung (adlung@de.ibm.com)
9 * Cornelia Huck (cohuck@de.ibm.com)
10 * Arnd Bergmann (arndb@de.ibm.com)
13 #include <linux/module.h>
14 #include <linux/config.h>
15 #include <linux/slab.h>
16 #include <linux/init.h>
17 #include <linux/device.h>
23 #include "cio_debug.h"
27 static struct channel_path *chps[NR_CHPIDS];
29 static void *sei_page;
31 static int new_channel_path(int chpid);
34 set_chp_logically_online(int chp, int onoff)
36 chps[chp]->state = onoff;
40 get_chp_status(int chp)
42 return (chps[chp] ? chps[chp]->state : -ENODEV);
46 chsc_validate_chpids(struct subchannel *sch)
50 for (chp = 0; chp <= 7; chp++) {
52 if (!get_chp_status(sch->schib.pmcw.chpid[chp]))
53 /* disable using this path */
59 chpid_is_actually_online(int chp)
63 state = get_chp_status(chp);
66 queue_work(slow_path_wq, &slow_path_work);
71 /* FIXME: this is _always_ called for every subchannel. shouldn't we
72 * process more than one at a time? */
74 chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
79 struct chsc_header request;
81 u16 f_sch; /* first subchannel */
83 u16 l_sch; /* last subchannel */
85 struct chsc_header response;
89 u8 st : 3; /* subchannel type */
91 u8 unit_addr; /* unit address */
92 u16 devno; /* device number */
95 u16 sch; /* subchannel */
96 u8 chpid[8]; /* chpids 0-7 */
97 u16 fla[8]; /* full link addresses 0-7 */
102 ssd_area->request = (struct chsc_header) {
107 ssd_area->f_sch = sch->schid.sch_no;
108 ssd_area->l_sch = sch->schid.sch_no;
110 ccode = chsc(ssd_area);
112 pr_debug("chsc returned with ccode = %d\n", ccode);
113 return (ccode == 3) ? -ENODEV : -EBUSY;
116 switch (ssd_area->response.code) {
117 case 0x0001: /* everything ok */
120 CIO_CRW_EVENT(2, "Invalid command!\n");
123 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
126 CIO_CRW_EVENT(2, "Model does not provide ssd\n");
129 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
130 ssd_area->response.code);
135 * ssd_area->st stores the type of the detected
136 * subchannel, with the following definitions:
138 * 0: I/O subchannel: All fields have meaning
139 * 1: CHSC subchannel: Only sch_val, st and sch
141 * 2: Message subchannel: All fields except unit_addr
143 * 3: ADM subchannel: Only sch_val, st and sch
146 * Other types are currently undefined.
148 if (ssd_area->st > 3) { /* uhm, that looks strange... */
149 CIO_CRW_EVENT(0, "Strange subchannel type %d"
150 " for sch %04x\n", ssd_area->st,
153 * There may have been a new subchannel type defined in the
154 * time since this code was written; since we don't know which
155 * fields have meaning and what to do with it we just jump out
159 const char *type[4] = {"I/O", "chsc", "message", "ADM"};
160 CIO_CRW_EVENT(6, "ssd: sch %04x is %s subchannel\n",
161 sch->schid.sch_no, type[ssd_area->st]);
163 sch->ssd_info.valid = 1;
164 sch->ssd_info.type = ssd_area->st;
167 if (ssd_area->st == 0 || ssd_area->st == 2) {
168 for (j = 0; j < 8; j++) {
169 if (!((0x80 >> j) & ssd_area->path_mask &
170 ssd_area->fla_valid_mask))
172 sch->ssd_info.chpid[j] = ssd_area->chpid[j];
173 sch->ssd_info.fla[j] = ssd_area->fla[j];
180 css_get_ssd_info(struct subchannel *sch)
185 page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
188 spin_lock_irq(&sch->lock);
189 ret = chsc_get_sch_desc_irq(sch, page);
191 static int cio_chsc_err_msg;
193 if (!cio_chsc_err_msg) {
195 "chsc_get_sch_descriptions:"
196 " Error %d while doing chsc; "
197 "processing some machine checks may "
199 cio_chsc_err_msg = 1;
202 spin_unlock_irq(&sch->lock);
203 free_page((unsigned long)page);
206 /* Allocate channel path structures, if needed. */
207 for (j = 0; j < 8; j++) {
208 chpid = sch->ssd_info.chpid[j];
209 if (chpid && (get_chp_status(chpid) < 0))
210 new_channel_path(chpid);
217 s390_subchannel_remove_chpid(struct device *dev, void *data)
221 struct subchannel *sch;
225 sch = to_subchannel(dev);
227 for (j = 0; j < 8; j++)
228 if (sch->schib.pmcw.chpid[j] == *chpid)
234 spin_lock(&sch->lock);
236 stsch(sch->schid, &schib);
239 memcpy(&sch->schib, &schib, sizeof(struct schib));
240 /* Check for single path devices. */
241 if (sch->schib.pmcw.pim == 0x80)
243 if (sch->vpm == mask)
246 if ((sch->schib.scsw.actl & (SCSW_ACTL_CLEAR_PEND |
247 SCSW_ACTL_HALT_PEND |
248 SCSW_ACTL_START_PEND |
249 SCSW_ACTL_RESUME_PEND)) &&
250 (sch->schib.pmcw.lpum == mask)) {
251 int cc = cio_cancel(sch);
261 if (sch->driver && sch->driver->termination)
262 sch->driver->termination(&sch->dev);
265 } else if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
266 (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
267 (sch->schib.pmcw.lpum == mask)) {
274 if (sch->driver && sch->driver->termination)
275 sch->driver->termination(&sch->dev);
279 /* trigger path verification. */
280 if (sch->driver && sch->driver->verify)
281 sch->driver->verify(&sch->dev);
283 spin_unlock(&sch->lock);
286 spin_unlock(&sch->lock);
288 if (css_enqueue_subchannel_slow(sch->schid)) {
289 css_clear_subchannel_slow_list();
296 s390_set_chpid_offline( __u8 chpid)
300 sprintf(dbf_txt, "chpr%x", chpid);
301 CIO_TRACE_EVENT(2, dbf_txt);
303 if (get_chp_status(chpid) <= 0)
306 bus_for_each_dev(&css_bus_type, NULL, &chpid,
307 s390_subchannel_remove_chpid);
309 if (need_rescan || css_slow_subchannels_exist())
310 queue_work(slow_path_wq, &slow_path_work);
313 struct res_acc_data {
314 struct channel_path *chp;
320 s390_process_res_acc_sch(struct res_acc_data *res_data, struct subchannel *sch)
327 for (chp = 0; chp <= 7; chp++)
329 * check if chpid is in information updated by ssd
331 if (sch->ssd_info.valid &&
332 sch->ssd_info.chpid[chp] == res_data->chp->id &&
333 (sch->ssd_info.fla[chp] & res_data->fla_mask)
343 * Do a stsch to update our subchannel structure with the
344 * new path information and eventually check for logically
347 ccode = stsch(sch->schid, &sch->schib);
355 s390_process_res_acc_new_sch(struct subchannel_id schid)
360 * We don't know the device yet, but since a path
361 * may be available now to the device we'll have
362 * to do recognition again.
363 * Since we don't have any idea about which chpid
364 * that beast may be on we'll have to do a stsch
365 * on all devices, grr...
367 if (stsch(schid, &schib))
369 return need_rescan ? -EAGAIN : -ENXIO;
371 /* Put it on the slow path. */
372 ret = css_enqueue_subchannel_slow(schid);
374 css_clear_subchannel_slow_list();
382 __s390_process_res_acc(struct subchannel_id schid, void *data)
384 int chp_mask, old_lpm;
385 struct res_acc_data *res_data;
386 struct subchannel *sch;
388 res_data = (struct res_acc_data *)data;
389 sch = get_subchannel_by_schid(schid);
391 /* Check if a subchannel is newly available. */
392 return s390_process_res_acc_new_sch(schid);
394 spin_lock_irq(&sch->lock);
396 chp_mask = s390_process_res_acc_sch(res_data, sch);
399 spin_unlock_irq(&sch->lock);
403 sch->lpm = ((sch->schib.pmcw.pim &
404 sch->schib.pmcw.pam &
406 | chp_mask) & sch->opm;
407 if (!old_lpm && sch->lpm)
408 device_trigger_reprobe(sch);
409 else if (sch->driver && sch->driver->verify)
410 sch->driver->verify(&sch->dev);
412 spin_unlock_irq(&sch->lock);
413 put_device(&sch->dev);
414 return (res_data->fla_mask == 0xffff) ? -ENODEV : 0;
419 s390_process_res_acc (struct res_acc_data *res_data)
424 sprintf(dbf_txt, "accpr%x", res_data->chp->id);
425 CIO_TRACE_EVENT( 2, dbf_txt);
426 if (res_data->fla != 0) {
427 sprintf(dbf_txt, "fla%x", res_data->fla);
428 CIO_TRACE_EVENT( 2, dbf_txt);
432 * I/O resources may have become accessible.
433 * Scan through all subchannels that may be concerned and
434 * do a validation on those.
435 * The more information we have (info), the less scanning
436 * will we have to do.
438 rc = for_each_subchannel(__s390_process_res_acc, res_data);
439 if (css_slow_subchannels_exist())
441 else if (rc != -EAGAIN)
447 __get_chpid_from_lir(void *data)
453 /* incident-node descriptor */
455 /* attached-node descriptor */
457 /* incident-specific information */
461 lir = (struct lir*) data;
463 /* NULL link incident record */
465 if (!(lir->indesc[0]&0xc0000000))
466 /* node descriptor not valid */
468 if (!(lir->indesc[0]&0x10000000))
469 /* don't handle device-type nodes - FIXME */
471 /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
473 return (u16) (lir->indesc[0]&0x000000ff);
477 chsc_process_crw(void)
480 struct res_acc_data res_data;
482 struct chsc_header request;
486 struct chsc_header response;
489 u8 vf; /* validity flags */
490 u8 rs; /* reporting source */
491 u8 cc; /* content code */
492 u16 fla; /* full link address */
493 u16 rsid; /* reporting source id */
496 u32 ccdf[96]; /* content-code dependent field */
497 /* ccdf has to be big enough for a link-incident record */
503 * build the chsc request block for store event information
505 * This function is only called by the machine check handler thread,
506 * so we don't need locking for the sei_page.
510 CIO_TRACE_EVENT( 2, "prcss");
514 memset(sei_area, 0, sizeof(*sei_area));
515 memset(&res_data, 0, sizeof(struct res_acc_data));
516 sei_area->request = (struct chsc_header) {
521 ccode = chsc(sei_area);
525 switch (sei_area->response.code) {
526 /* for debug purposes, check for problems */
528 CIO_CRW_EVENT(4, "chsc_process_crw: event information "
529 "successfully stored\n");
530 break; /* everything ok */
533 "chsc_process_crw: invalid command!\n");
536 CIO_CRW_EVENT(2, "chsc_process_crw: error in chsc "
540 CIO_CRW_EVENT(2, "chsc_process_crw: no event "
541 "information stored\n");
544 CIO_CRW_EVENT(2, "chsc_process_crw: chsc response %d\n",
545 sei_area->response.code);
549 /* Check if we might have lost some information. */
550 if (sei_area->flags & 0x40)
551 CIO_CRW_EVENT(2, "chsc_process_crw: Event information "
552 "has been lost due to overflow!\n");
554 if (sei_area->rs != 4) {
555 CIO_CRW_EVENT(2, "chsc_process_crw: reporting source "
556 "(%04X) isn't a chpid!\n",
561 /* which kind of information was stored? */
562 switch (sei_area->cc) {
563 case 1: /* link incident*/
564 CIO_CRW_EVENT(4, "chsc_process_crw: "
565 "channel subsystem reports link incident,"
566 " reporting source is chpid %x\n",
568 chpid = __get_chpid_from_lir(sei_area->ccdf);
570 CIO_CRW_EVENT(4, "%s: Invalid LIR, skipping\n",
573 s390_set_chpid_offline(chpid);
576 case 2: /* i/o resource accessibiliy */
577 CIO_CRW_EVENT(4, "chsc_process_crw: "
578 "channel subsystem reports some I/O "
579 "devices may have become accessible\n");
580 pr_debug("Data received after sei: \n");
581 pr_debug("Validity flags: %x\n", sei_area->vf);
583 /* allocate a new channel path structure, if needed */
584 status = get_chp_status(sei_area->rsid);
586 new_channel_path(sei_area->rsid);
589 res_data.chp = chps[sei_area->rsid];
590 pr_debug("chpid: %x", sei_area->rsid);
591 if ((sei_area->vf & 0xc0) != 0) {
592 res_data.fla = sei_area->fla;
593 if ((sei_area->vf & 0xc0) == 0xc0) {
594 pr_debug(" full link addr: %x",
596 res_data.fla_mask = 0xffff;
598 pr_debug(" link addr: %x",
600 res_data.fla_mask = 0xff00;
603 ret = s390_process_res_acc(&res_data);
607 default: /* other stuff */
608 CIO_CRW_EVENT(4, "chsc_process_crw: event %d\n",
612 } while (sei_area->flags & 0x80);
617 __chp_add_new_sch(struct subchannel_id schid)
622 if (stsch(schid, &schib))
624 return need_rescan ? -EAGAIN : -ENXIO;
626 /* Put it on the slow path. */
627 ret = css_enqueue_subchannel_slow(schid);
629 css_clear_subchannel_slow_list();
638 __chp_add(struct subchannel_id schid, void *data)
641 struct channel_path *chp;
642 struct subchannel *sch;
644 chp = (struct channel_path *)data;
645 sch = get_subchannel_by_schid(schid);
647 /* Check if the subchannel is now available. */
648 return __chp_add_new_sch(schid);
649 spin_lock(&sch->lock);
651 if (sch->schib.pmcw.chpid[i] == chp->id) {
652 if (stsch(sch->schid, &sch->schib) != 0) {
654 spin_unlock(&sch->lock);
660 spin_unlock(&sch->lock);
663 sch->lpm = ((sch->schib.pmcw.pim &
664 sch->schib.pmcw.pam &
666 | 0x80 >> i) & sch->opm;
668 if (sch->driver && sch->driver->verify)
669 sch->driver->verify(&sch->dev);
671 spin_unlock(&sch->lock);
672 put_device(&sch->dev);
682 if (!get_chp_status(chpid))
683 return 0; /* no need to do the rest */
685 sprintf(dbf_txt, "cadd%x", chpid);
686 CIO_TRACE_EVENT(2, dbf_txt);
688 rc = for_each_subchannel(__chp_add, chps[chpid]);
689 if (css_slow_subchannels_exist())
697 * Handling of crw machine checks with channel path source.
700 chp_process_crw(int chpid, int on)
703 /* Path has gone. We use the link incident routine.*/
704 s390_set_chpid_offline(chpid);
705 return 0; /* De-register is async anyway. */
708 * Path has come. Allocate a new channel path structure,
711 if (get_chp_status(chpid) < 0)
712 new_channel_path(chpid);
713 /* Avoid the extra overhead in process_rec_acc. */
714 return chp_add(chpid);
718 __check_for_io_and_kill(struct subchannel *sch, int index)
722 if (!device_is_online(sch))
723 /* cio could be doing I/O. */
725 cc = stsch(sch->schid, &sch->schib);
728 if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index)) {
729 device_set_waiting(sch);
736 __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
741 if (!sch->ssd_info.valid)
744 spin_lock_irqsave(&sch->lock, flags);
746 for (chp = 0; chp < 8; chp++) {
747 if (sch->ssd_info.chpid[chp] != chpid)
751 sch->opm |= (0x80 >> chp);
752 sch->lpm |= (0x80 >> chp);
754 device_trigger_reprobe(sch);
755 else if (sch->driver && sch->driver->verify)
756 sch->driver->verify(&sch->dev);
758 sch->opm &= ~(0x80 >> chp);
759 sch->lpm &= ~(0x80 >> chp);
761 * Give running I/O a grace period in which it
762 * can successfully terminate, even using the
763 * just varied off path. Then kill it.
765 if (!__check_for_io_and_kill(sch, chp) && !sch->lpm) {
766 if (css_enqueue_subchannel_slow(sch->schid)) {
767 css_clear_subchannel_slow_list();
770 } else if (sch->driver && sch->driver->verify)
771 sch->driver->verify(&sch->dev);
775 spin_unlock_irqrestore(&sch->lock, flags);
779 s390_subchannel_vary_chpid_off(struct device *dev, void *data)
781 struct subchannel *sch;
784 sch = to_subchannel(dev);
787 __s390_subchannel_vary_chpid(sch, *chpid, 0);
792 s390_subchannel_vary_chpid_on(struct device *dev, void *data)
794 struct subchannel *sch;
797 sch = to_subchannel(dev);
800 __s390_subchannel_vary_chpid(sch, *chpid, 1);
805 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
808 struct subchannel *sch;
810 sch = get_subchannel_by_schid(schid);
812 put_device(&sch->dev);
815 if (stsch(schid, &schib))
818 /* Put it on the slow path. */
819 if (css_enqueue_subchannel_slow(schid)) {
820 css_clear_subchannel_slow_list();
828 * Function: s390_vary_chpid
829 * Varies the specified chpid online or offline
832 s390_vary_chpid( __u8 chpid, int on)
837 sprintf(dbf_text, on?"varyon%x":"varyoff%x", chpid);
838 CIO_TRACE_EVENT( 2, dbf_text);
840 status = get_chp_status(chpid);
842 printk(KERN_ERR "Can't vary unknown chpid %02X\n", chpid);
846 if (!on && !status) {
847 printk(KERN_ERR "chpid %x is already offline\n", chpid);
851 set_chp_logically_online(chpid, on);
854 * Redo PathVerification on the devices the chpid connects to
857 bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
858 s390_subchannel_vary_chpid_on :
859 s390_subchannel_vary_chpid_off);
861 /* Scan for new devices on varied on path. */
862 for_each_subchannel(__s390_vary_chpid_on, NULL);
863 if (need_rescan || css_slow_subchannels_exist())
864 queue_work(slow_path_wq, &slow_path_work);
869 * Files for the channel path entries.
872 chp_status_show(struct device *dev, struct device_attribute *attr, char *buf)
874 struct channel_path *chp = container_of(dev, struct channel_path, dev);
878 return (get_chp_status(chp->id) ? sprintf(buf, "online\n") :
879 sprintf(buf, "offline\n"));
883 chp_status_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
885 struct channel_path *cp = container_of(dev, struct channel_path, dev);
890 num_args = sscanf(buf, "%5s", cmd);
894 if (!strnicmp(cmd, "on", 2))
895 error = s390_vary_chpid(cp->id, 1);
896 else if (!strnicmp(cmd, "off", 3))
897 error = s390_vary_chpid(cp->id, 0);
901 return error < 0 ? error : count;
905 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
908 chp_type_show(struct device *dev, struct device_attribute *attr, char *buf)
910 struct channel_path *chp = container_of(dev, struct channel_path, dev);
914 return sprintf(buf, "%x\n", chp->desc.desc);
917 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
919 static struct attribute * chp_attrs[] = {
920 &dev_attr_status.attr,
925 static struct attribute_group chp_attr_group = {
930 chp_release(struct device *dev)
932 struct channel_path *cp;
934 cp = container_of(dev, struct channel_path, dev);
939 chsc_determine_channel_path_description(int chpid,
940 struct channel_path_desc *desc)
945 struct chsc_header request;
951 struct chsc_header response;
953 struct channel_path_desc desc;
956 scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
960 scpd_area->request = (struct chsc_header) {
965 scpd_area->first_chpid = chpid;
966 scpd_area->last_chpid = chpid;
968 ccode = chsc(scpd_area);
970 ret = (ccode == 3) ? -ENODEV : -EBUSY;
974 switch (scpd_area->response.code) {
975 case 0x0001: /* Success. */
976 memcpy(desc, &scpd_area->desc,
977 sizeof(struct channel_path_desc));
980 case 0x0003: /* Invalid block. */
981 case 0x0007: /* Invalid format. */
982 case 0x0008: /* Other invalid block. */
983 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
986 case 0x0004: /* Command not provided in model. */
987 CIO_CRW_EVENT(2, "Model does not provide scpd\n");
991 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
992 scpd_area->response.code);
996 free_page((unsigned long)scpd_area);
1001 * Entries for chpids on the system bus.
1002 * This replaces /proc/chpids.
1005 new_channel_path(int chpid)
1007 struct channel_path *chp;
1010 chp = kmalloc(sizeof(struct channel_path), GFP_KERNEL);
1013 memset(chp, 0, sizeof(struct channel_path));
1015 /* fill in status, etc. */
1018 chp->dev = (struct device) {
1019 .parent = &css_bus_device,
1020 .release = chp_release,
1022 snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp0.%x", chpid);
1024 /* Obtain channel path description and fill it in. */
1025 ret = chsc_determine_channel_path_description(chpid, &chp->desc);
1029 /* make it known to the system */
1030 ret = device_register(&chp->dev);
1032 printk(KERN_WARNING "%s: could not register %02x\n",
1036 ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
1038 device_unregister(&chp->dev);
1049 chsc_get_chp_desc(struct subchannel *sch, int chp_no)
1051 struct channel_path *chp;
1052 struct channel_path_desc *desc;
1054 chp = chps[sch->schib.pmcw.chpid[chp_no]];
1057 desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
1060 memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
1066 chsc_alloc_sei_area(void)
1068 sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1070 printk(KERN_WARNING"Can't allocate page for processing of " \
1071 "chsc machine checks!\n");
1072 return (sei_page ? 0 : -ENOMEM);
1075 subsys_initcall(chsc_alloc_sei_area);
1077 struct css_general_char css_general_characteristics;
1078 struct css_chsc_char css_chsc_characteristics;
1081 chsc_determine_css_characteristics(void)
1085 struct chsc_header request;
1089 struct chsc_header response;
1091 u32 general_char[510];
1095 scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1097 printk(KERN_WARNING"cio: Was not able to determine available" \
1098 "CHSCs due to no memory.\n");
1102 scsc_area->request = (struct chsc_header) {
1107 result = chsc(scsc_area);
1109 printk(KERN_WARNING"cio: Was not able to determine " \
1110 "available CHSCs, cc=%i.\n", result);
1115 if (scsc_area->response.code != 1) {
1116 printk(KERN_WARNING"cio: Was not able to determine " \
1117 "available CHSCs.\n");
1121 memcpy(&css_general_characteristics, scsc_area->general_char,
1122 sizeof(css_general_characteristics));
1123 memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1124 sizeof(css_chsc_characteristics));
1126 free_page ((unsigned long) scsc_area);
1130 EXPORT_SYMBOL_GPL(css_general_characteristics);
1131 EXPORT_SYMBOL_GPL(css_chsc_characteristics);