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authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-16 14:48:13 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-16 14:48:13 -0400
commit6a454f71d795368c00d9c329b60cc4d58929e7bc (patch)
treef85a7ed30ba1d25606a22cc07e7383e73fc49972 /drivers/char
parentd613839ef987d20f7c9347732b452efd921b97d9 (diff)
parent155af2f95f905c830688dd0ca7c7cac4107334fd (diff)
Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (33 commits) [S390] s390: hibernation support for s390 [S390] pm: dcssblk power management callbacks. [S390] pm: monreader power management callbacks. [S390] pm: monwriter power management callbacks. [S390] pm: memory hotplug power management callbacks [S390] pm: con3270 power management callbacks. [S390] pm: smsgiucv power management callbacks. [S390] pm: hvc_iucv power management callbacks [S390] PM: af_iucv power management callbacks. [S390] pm: netiucv power management callbacks. [S390] pm: iucv power management callbacks. [S390] iucv: establish reboot notifier [S390] pm: power management support for SCLP drivers. [S390] pm: tape power management callbacks [S390] pm: vmlogrdr power management callbacks [S390] pm: vmur driver power management callbacks [S390] pm: appldata power management callbacks [S390] pm: vmwatchdog power management callbacks. [S390] pm: zfcp driver power management callbacks [S390] pm: claw driver power management callbacks ...
Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/hvc_iucv.c204
1 files changed, 161 insertions, 43 deletions
diff --git a/drivers/char/hvc_iucv.c b/drivers/char/hvc_iucv.c
index 54481a887769..86105efb4eb6 100644
--- a/drivers/char/hvc_iucv.c
+++ b/drivers/char/hvc_iucv.c
@@ -4,7 +4,7 @@
4 * This HVC device driver provides terminal access using 4 * This HVC device driver provides terminal access using
5 * z/VM IUCV communication paths. 5 * z/VM IUCV communication paths.
6 * 6 *
7 * Copyright IBM Corp. 2008 7 * Copyright IBM Corp. 2008, 2009
8 * 8 *
9 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com> 9 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
10 */ 10 */
@@ -15,6 +15,7 @@
15#include <asm/ebcdic.h> 15#include <asm/ebcdic.h>
16#include <linux/ctype.h> 16#include <linux/ctype.h>
17#include <linux/delay.h> 17#include <linux/delay.h>
18#include <linux/device.h>
18#include <linux/init.h> 19#include <linux/init.h>
19#include <linux/mempool.h> 20#include <linux/mempool.h>
20#include <linux/moduleparam.h> 21#include <linux/moduleparam.h>
@@ -74,6 +75,7 @@ struct hvc_iucv_private {
74 wait_queue_head_t sndbuf_waitq; /* wait for send completion */ 75 wait_queue_head_t sndbuf_waitq; /* wait for send completion */
75 struct list_head tty_outqueue; /* outgoing IUCV messages */ 76 struct list_head tty_outqueue; /* outgoing IUCV messages */
76 struct list_head tty_inqueue; /* incoming IUCV messages */ 77 struct list_head tty_inqueue; /* incoming IUCV messages */
78 struct device *dev; /* device structure */
77}; 79};
78 80
79struct iucv_tty_buffer { 81struct iucv_tty_buffer {
@@ -542,7 +544,68 @@ static void flush_sndbuf_sync(struct hvc_iucv_private *priv)
542 544
543 if (sync_wait) 545 if (sync_wait)
544 wait_event_timeout(priv->sndbuf_waitq, 546 wait_event_timeout(priv->sndbuf_waitq,
545 tty_outqueue_empty(priv), HZ); 547 tty_outqueue_empty(priv), HZ/10);
548}
549
550/**
551 * hvc_iucv_hangup() - Sever IUCV path and schedule hvc tty hang up
552 * @priv: Pointer to hvc_iucv_private structure
553 *
554 * This routine severs an existing IUCV communication path and hangs
555 * up the underlying HVC terminal device.
556 * The hang-up occurs only if an IUCV communication path is established;
557 * otherwise there is no need to hang up the terminal device.
558 *
559 * The IUCV HVC hang-up is separated into two steps:
560 * 1. After the IUCV path has been severed, the iucv_state is set to
561 * IUCV_SEVERED.
562 * 2. Later, when the HVC thread calls hvc_iucv_get_chars(), the
563 * IUCV_SEVERED state causes the tty hang-up in the HVC layer.
564 *
565 * If the tty has not yet been opened, clean up the hvc_iucv_private
566 * structure to allow re-connects.
567 * If the tty has been opened, let get_chars() return -EPIPE to signal
568 * the HVC layer to hang up the tty and, if so, wake up the HVC thread
569 * to call get_chars()...
570 *
571 * Special notes on hanging up a HVC terminal instantiated as console:
572 * Hang-up: 1. do_tty_hangup() replaces file ops (= hung_up_tty_fops)
573 * 2. do_tty_hangup() calls tty->ops->close() for console_filp
574 * => no hangup notifier is called by HVC (default)
575 * 2. hvc_close() returns because of tty_hung_up_p(filp)
576 * => no delete notifier is called!
577 * Finally, the back-end is not being notified, thus, the tty session is
578 * kept active (TTY_OPEN) to be ready for re-connects.
579 *
580 * Locking: spin_lock(&priv->lock) w/o disabling bh
581 */
582static void hvc_iucv_hangup(struct hvc_iucv_private *priv)
583{
584 struct iucv_path *path;
585
586 path = NULL;
587 spin_lock(&priv->lock);
588 if (priv->iucv_state == IUCV_CONNECTED) {
589 path = priv->path;
590 priv->path = NULL;
591 priv->iucv_state = IUCV_SEVERED;
592 if (priv->tty_state == TTY_CLOSED)
593 hvc_iucv_cleanup(priv);
594 else
595 /* console is special (see above) */
596 if (priv->is_console) {
597 hvc_iucv_cleanup(priv);
598 priv->tty_state = TTY_OPENED;
599 } else
600 hvc_kick();
601 }
602 spin_unlock(&priv->lock);
603
604 /* finally sever path (outside of priv->lock due to lock ordering) */
605 if (path) {
606 iucv_path_sever(path, NULL);
607 iucv_path_free(path);
608 }
546} 609}
547 610
548/** 611/**
@@ -735,11 +798,8 @@ out_path_handled:
735 * @ipuser: User specified data for this path 798 * @ipuser: User specified data for this path
736 * (AF_IUCV: port/service name and originator port) 799 * (AF_IUCV: port/service name and originator port)
737 * 800 *
738 * The function also severs the path (as required by the IUCV protocol) and 801 * This function calls the hvc_iucv_hangup() function for the
739 * sets the iucv state to IUCV_SEVERED for the associated struct 802 * respective IUCV HVC terminal.
740 * hvc_iucv_private instance. Later, the IUCV_SEVERED state triggers a tty
741 * hangup (hvc_iucv_get_chars() / hvc_iucv_write()).
742 * If tty portion of the HVC is closed, clean up the outqueue.
743 * 803 *
744 * Locking: struct hvc_iucv_private->lock 804 * Locking: struct hvc_iucv_private->lock
745 */ 805 */
@@ -747,33 +807,7 @@ static void hvc_iucv_path_severed(struct iucv_path *path, u8 ipuser[16])
747{ 807{
748 struct hvc_iucv_private *priv = path->private; 808 struct hvc_iucv_private *priv = path->private;
749 809
750 spin_lock(&priv->lock); 810 hvc_iucv_hangup(priv);
751 priv->iucv_state = IUCV_SEVERED;
752
753 /* If the tty has not yet been opened, clean up the hvc_iucv_private
754 * structure to allow re-connects.
755 * This is also done for our console device because console hangups
756 * are handled specially and no notifier is called by HVC.
757 * The tty session is active (TTY_OPEN) and ready for re-connects...
758 *
759 * If it has been opened, let get_chars() return -EPIPE to signal the
760 * HVC layer to hang up the tty.
761 * If so, we need to wake up the HVC thread to call get_chars()...
762 */
763 priv->path = NULL;
764 if (priv->tty_state == TTY_CLOSED)
765 hvc_iucv_cleanup(priv);
766 else
767 if (priv->is_console) {
768 hvc_iucv_cleanup(priv);
769 priv->tty_state = TTY_OPENED;
770 } else
771 hvc_kick();
772 spin_unlock(&priv->lock);
773
774 /* finally sever path (outside of priv->lock due to lock ordering) */
775 iucv_path_sever(path, ipuser);
776 iucv_path_free(path);
777} 811}
778 812
779/** 813/**
@@ -853,6 +887,37 @@ static void hvc_iucv_msg_complete(struct iucv_path *path,
853 destroy_tty_buffer_list(&list_remove); 887 destroy_tty_buffer_list(&list_remove);
854} 888}
855 889
890/**
891 * hvc_iucv_pm_freeze() - Freeze PM callback
892 * @dev: IUVC HVC terminal device
893 *
894 * Sever an established IUCV communication path and
895 * trigger a hang-up of the underlying HVC terminal.
896 */
897static int hvc_iucv_pm_freeze(struct device *dev)
898{
899 struct hvc_iucv_private *priv = dev_get_drvdata(dev);
900
901 local_bh_disable();
902 hvc_iucv_hangup(priv);
903 local_bh_enable();
904
905 return 0;
906}
907
908/**
909 * hvc_iucv_pm_restore_thaw() - Thaw and restore PM callback
910 * @dev: IUVC HVC terminal device
911 *
912 * Wake up the HVC thread to trigger hang-up and respective
913 * HVC back-end notifier invocations.
914 */
915static int hvc_iucv_pm_restore_thaw(struct device *dev)
916{
917 hvc_kick();
918 return 0;
919}
920
856 921
857/* HVC operations */ 922/* HVC operations */
858static struct hv_ops hvc_iucv_ops = { 923static struct hv_ops hvc_iucv_ops = {
@@ -863,6 +928,20 @@ static struct hv_ops hvc_iucv_ops = {
863 .notifier_hangup = hvc_iucv_notifier_hangup, 928 .notifier_hangup = hvc_iucv_notifier_hangup,
864}; 929};
865 930
931/* Suspend / resume device operations */
932static struct dev_pm_ops hvc_iucv_pm_ops = {
933 .freeze = hvc_iucv_pm_freeze,
934 .thaw = hvc_iucv_pm_restore_thaw,
935 .restore = hvc_iucv_pm_restore_thaw,
936};
937
938/* IUCV HVC device driver */
939static struct device_driver hvc_iucv_driver = {
940 .name = KMSG_COMPONENT,
941 .bus = &iucv_bus,
942 .pm = &hvc_iucv_pm_ops,
943};
944
866/** 945/**
867 * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance 946 * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance
868 * @id: hvc_iucv_table index 947 * @id: hvc_iucv_table index
@@ -897,14 +976,12 @@ static int __init hvc_iucv_alloc(int id, unsigned int is_console)
897 /* set console flag */ 976 /* set console flag */
898 priv->is_console = is_console; 977 priv->is_console = is_console;
899 978
900 /* finally allocate hvc */ 979 /* allocate hvc device */
901 priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /* PAGE_SIZE */ 980 priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /* PAGE_SIZE */
902 HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256); 981 HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256);
903 if (IS_ERR(priv->hvc)) { 982 if (IS_ERR(priv->hvc)) {
904 rc = PTR_ERR(priv->hvc); 983 rc = PTR_ERR(priv->hvc);
905 free_page((unsigned long) priv->sndbuf); 984 goto out_error_hvc;
906 kfree(priv);
907 return rc;
908 } 985 }
909 986
910 /* notify HVC thread instead of using polling */ 987 /* notify HVC thread instead of using polling */
@@ -915,8 +992,45 @@ static int __init hvc_iucv_alloc(int id, unsigned int is_console)
915 memcpy(priv->srv_name, name, 8); 992 memcpy(priv->srv_name, name, 8);
916 ASCEBC(priv->srv_name, 8); 993 ASCEBC(priv->srv_name, 8);
917 994
995 /* create and setup device */
996 priv->dev = kzalloc(sizeof(*priv->dev), GFP_KERNEL);
997 if (!priv->dev) {
998 rc = -ENOMEM;
999 goto out_error_dev;
1000 }
1001 dev_set_name(priv->dev, "hvc_iucv%d", id);
1002 dev_set_drvdata(priv->dev, priv);
1003 priv->dev->bus = &iucv_bus;
1004 priv->dev->parent = iucv_root;
1005 priv->dev->driver = &hvc_iucv_driver;
1006 priv->dev->release = (void (*)(struct device *)) kfree;
1007 rc = device_register(priv->dev);
1008 if (rc) {
1009 kfree(priv->dev);
1010 goto out_error_dev;
1011 }
1012
918 hvc_iucv_table[id] = priv; 1013 hvc_iucv_table[id] = priv;
919 return 0; 1014 return 0;
1015
1016out_error_dev:
1017 hvc_remove(priv->hvc);
1018out_error_hvc:
1019 free_page((unsigned long) priv->sndbuf);
1020 kfree(priv);
1021
1022 return rc;
1023}
1024
1025/**
1026 * hvc_iucv_destroy() - Destroy and free hvc_iucv_private instances
1027 */
1028static void __init hvc_iucv_destroy(struct hvc_iucv_private *priv)
1029{
1030 hvc_remove(priv->hvc);
1031 device_unregister(priv->dev);
1032 free_page((unsigned long) priv->sndbuf);
1033 kfree(priv);
920} 1034}
921 1035
922/** 1036/**
@@ -1109,6 +1223,11 @@ static int __init hvc_iucv_init(void)
1109 goto out_error; 1223 goto out_error;
1110 } 1224 }
1111 1225
1226 /* register IUCV HVC device driver */
1227 rc = driver_register(&hvc_iucv_driver);
1228 if (rc)
1229 goto out_error;
1230
1112 /* parse hvc_iucv_allow string and create z/VM user ID filter list */ 1231 /* parse hvc_iucv_allow string and create z/VM user ID filter list */
1113 if (hvc_iucv_filter_string) { 1232 if (hvc_iucv_filter_string) {
1114 rc = hvc_iucv_setup_filter(hvc_iucv_filter_string); 1233 rc = hvc_iucv_setup_filter(hvc_iucv_filter_string);
@@ -1183,15 +1302,14 @@ out_error_iucv:
1183 iucv_unregister(&hvc_iucv_handler, 0); 1302 iucv_unregister(&hvc_iucv_handler, 0);
1184out_error_hvc: 1303out_error_hvc:
1185 for (i = 0; i < hvc_iucv_devices; i++) 1304 for (i = 0; i < hvc_iucv_devices; i++)
1186 if (hvc_iucv_table[i]) { 1305 if (hvc_iucv_table[i])
1187 if (hvc_iucv_table[i]->hvc) 1306 hvc_iucv_destroy(hvc_iucv_table[i]);
1188 hvc_remove(hvc_iucv_table[i]->hvc);
1189 kfree(hvc_iucv_table[i]);
1190 }
1191out_error_memory: 1307out_error_memory:
1192 mempool_destroy(hvc_iucv_mempool); 1308 mempool_destroy(hvc_iucv_mempool);
1193 kmem_cache_destroy(hvc_iucv_buffer_cache); 1309 kmem_cache_destroy(hvc_iucv_buffer_cache);
1194out_error: 1310out_error:
1311 if (hvc_iucv_filter)
1312 kfree(hvc_iucv_filter);
1195 hvc_iucv_devices = 0; /* ensure that we do not provide any device */ 1313 hvc_iucv_devices = 0; /* ensure that we do not provide any device */
1196 return rc; 1314 return rc;
1197} 1315}