2 * IBM eServer Hypervisor Virtual Console Server Device Driver
3 * Copyright (C) 2003, 2004 IBM Corp.
4 * Ryan S. Arnold (rsa@us.ibm.com)
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 * Author(s) : Ryan S. Arnold <rsa@us.ibm.com>
22 * This is the device driver for the IBM Hypervisor Virtual Console Server,
23 * "hvcs". The IBM hvcs provides a tty driver interface to allow Linux
24 * user space applications access to the system consoles of logically
25 * partitioned operating systems, e.g. Linux, running on the same partitioned
26 * Power5 ppc64 system. Physical hardware consoles per partition are not
27 * practical on this hardware so system consoles are accessed by this driver
28 * using inter-partition firmware interfaces to virtual terminal devices.
30 * A vty is known to the HMC as a "virtual serial server adapter". It is a
31 * virtual terminal device that is created by firmware upon partition creation
32 * to act as a partitioned OS's console device.
34 * Firmware dynamically (via hotplug) exposes vty-servers to a running ppc64
35 * Linux system upon their creation by the HMC or their exposure during boot.
36 * The non-user interactive backend of this driver is implemented as a vio
37 * device driver so that it can receive notification of vty-server lifetimes
38 * after it registers with the vio bus to handle vty-server probe and remove
41 * Many vty-servers can be configured to connect to one vty, but a vty can
42 * only be actively connected to by a single vty-server, in any manner, at one
43 * time. If the HMC is currently hosting the console for a target Linux
44 * partition; attempts to open the tty device to the partition's console using
45 * the hvcs on any partition will return -EBUSY with every open attempt until
46 * the HMC frees the connection between its vty-server and the desired
47 * partition's vty device. Conversely, a vty-server may only be connected to
48 * a single vty at one time even though it may have several configured vty
49 * partner possibilities.
51 * Firmware does not provide notification of vty partner changes to this
52 * driver. This means that an HMC Super Admin may add or remove partner vtys
53 * from a vty-server's partner list but the changes will not be signaled to
54 * the vty-server. Firmware only notifies the driver when a vty-server is
55 * added or removed from the system. To compensate for this deficiency, this
56 * driver implements a sysfs update attribute which provides a method for
57 * rescanning partner information upon a user's request.
59 * Each vty-server, prior to being exposed to this driver is reference counted
60 * using the 2.6 Linux kernel kobject construct. This kobject is also used by
61 * the vio bus to provide a vio device sysfs entry that this driver attaches
62 * device specific attributes to, including partner information. The vio bus
63 * framework also provides a sysfs entry for each vio driver. The hvcs driver
64 * provides driver attributes in this entry.
66 * For direction on installation and usage of this driver please reference
67 * Documentation/powerpc/hvcs.txt.
70 #include <linux/device.h>
71 #include <linux/init.h>
72 #include <linux/interrupt.h>
73 #include <linux/kernel.h>
74 #include <linux/kobject.h>
75 #include <linux/kthread.h>
76 #include <linux/list.h>
77 #include <linux/major.h>
78 #include <linux/module.h>
79 #include <linux/moduleparam.h>
80 #include <linux/sched.h>
81 #include <linux/spinlock.h>
82 #include <linux/stat.h>
83 #include <linux/tty.h>
84 #include <linux/tty_flip.h>
85 #include <asm/hvconsole.h>
86 #include <asm/hvcserver.h>
87 #include <asm/uaccess.h>
91 * 1.3.0 -> 1.3.1 In hvcs_open memset(..,0x00,..) instead of memset(..,0x3F,00).
92 * Removed braces around single statements following conditionals. Removed '=
93 * 0' after static int declarations since these default to zero. Removed
94 * list_for_each_safe() and replaced with list_for_each_entry() in
95 * hvcs_get_by_index(). The 'safe' version is un-needed now that the driver is
96 * using spinlocks. Changed spin_lock_irqsave() to spin_lock() when locking
97 * hvcs_structs_lock and hvcs_pi_lock since these are not touched in an int
98 * handler. Initialized hvcs_structs_lock and hvcs_pi_lock to
99 * SPIN_LOCK_UNLOCKED at declaration time rather than in hvcs_module_init().
100 * Added spin_lock around list_del() in destroy_hvcs_struct() to protect the
101 * list traversals from a deletion. Removed '= NULL' from pointer declaration
102 * statements since they are initialized NULL by default. Removed wmb()
103 * instances from hvcs_try_write(). They probably aren't needed with locking in
104 * place. Added check and cleanup for hvcs_pi_buff = kmalloc() in
105 * hvcs_module_init(). Exposed hvcs_struct.index via a sysfs attribute so that
106 * the coupling between /dev/hvcs* and a vty-server can be automatically
107 * determined. Moved kobject_put() in hvcs_open outside of the
108 * spin_unlock_irqrestore().
110 * 1.3.1 -> 1.3.2 Changed method for determining hvcs_struct->index and had it
111 * align with how the tty layer always assigns the lowest index available. This
112 * change resulted in a list of ints that denotes which indexes are available.
113 * Device additions and removals use the new hvcs_get_index() and
114 * hvcs_return_index() helper functions. The list is created with
115 * hvsc_alloc_index_list() and it is destroyed with hvcs_free_index_list().
116 * Without these fixes hotplug vty-server adapter support goes crazy with this
117 * driver if the user removes a vty-server adapter. Moved free_irq() outside of
118 * the hvcs_final_close() function in order to get it out of the spinlock.
119 * Rearranged hvcs_close(). Cleaned up some printks and did some housekeeping
120 * on the changelog. Removed local CLC_LENGTH and used HVCS_CLC_LENGTH from
121 * arch/ppc64/hvcserver.h.
123 * 1.3.2 -> 1.3.3 Replaced yield() in hvcs_close() with tty_wait_until_sent() to
124 * prevent possible lockup with realtime scheduling as similarily pointed out by
125 * akpm in hvc_console. Changed resulted in the removal of hvcs_final_close()
126 * to reorder cleanup operations and prevent discarding of pending data during
127 * an hvcs_close(). Removed spinlock protection of hvcs_struct data members in
128 * hvcs_write_room() and hvcs_chars_in_buffer() because they aren't needed.
131 #define HVCS_DRIVER_VERSION "1.3.3"
133 MODULE_AUTHOR("Ryan S. Arnold <rsa@us.ibm.com>");
134 MODULE_DESCRIPTION("IBM hvcs (Hypervisor Virtual Console Server) Driver");
135 MODULE_LICENSE("GPL");
136 MODULE_VERSION(HVCS_DRIVER_VERSION
);
139 * Wait this long per iteration while trying to push buffered data to the
140 * hypervisor before allowing the tty to complete a close operation.
142 #define HVCS_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
145 * Since the Linux TTY code does not currently (2-04-2004) support dynamic
146 * addition of tty derived devices and we shouldn't allocate thousands of
147 * tty_device pointers when the number of vty-server & vty partner connections
148 * will most often be much lower than this, we'll arbitrarily allocate
149 * HVCS_DEFAULT_SERVER_ADAPTERS tty_structs and cdev's by default when we
150 * register the tty_driver. This can be overridden using an insmod parameter.
152 #define HVCS_DEFAULT_SERVER_ADAPTERS 64
155 * The user can't insmod with more than HVCS_MAX_SERVER_ADAPTERS hvcs device
156 * nodes as a sanity check. Theoretically there can be over 1 Billion
157 * vty-server & vty partner connections.
159 #define HVCS_MAX_SERVER_ADAPTERS 1024
162 * We let Linux assign us a major number and we start the minors at zero. There
163 * is no intuitive mapping between minor number and the target vty-server
164 * adapter except that each new vty-server adapter is always assigned to the
165 * smallest minor number available.
167 #define HVCS_MINOR_START 0
170 * The hcall interface involves putting 8 chars into each of two registers.
171 * We load up those 2 registers (in arch/ppc64/hvconsole.c) by casting char[16]
172 * to long[2]. It would work without __ALIGNED__, but a little (tiny) bit
173 * slower because an unaligned load is slower than aligned load.
175 #define __ALIGNED__ __attribute__((__aligned__(8)))
178 * How much data can firmware send with each hvc_put_chars()? Maybe this
179 * should be moved into an architecture specific area.
181 #define HVCS_BUFF_LEN 16
184 * This is the maximum amount of data we'll let the user send us (hvcs_write) at
185 * once in a chunk as a sanity check.
187 #define HVCS_MAX_FROM_USER 4096
190 * Be careful when adding flags to this line discipline. Don't add anything
191 * that will cause echoing or we'll go into recursive loop echoing chars back
192 * and forth with the console drivers.
194 static struct termios hvcs_tty_termios
= {
195 .c_iflag
= IGNBRK
| IGNPAR
,
197 .c_cflag
= B38400
| CS8
| CREAD
| HUPCL
,
202 * This value is used to take the place of a command line parameter when the
203 * module is inserted. It starts as -1 and stays as such if the user doesn't
204 * specify a module insmod parameter. If they DO specify one then it is set to
205 * the value of the integer passed in.
207 static int hvcs_parm_num_devs
= -1;
208 module_param(hvcs_parm_num_devs
, int, 0);
210 char hvcs_driver_name
[] = "hvcs";
211 char hvcs_device_node
[] = "hvcs";
212 char hvcs_driver_string
[]
213 = "IBM hvcs (Hypervisor Virtual Console Server) Driver";
215 /* Status of partner info rescan triggered via sysfs. */
216 static int hvcs_rescan_status
;
218 static struct tty_driver
*hvcs_tty_driver
;
221 * In order to be somewhat sane this driver always associates the hvcs_struct
222 * index element with the numerically equal tty->index. This means that a
223 * hotplugged vty-server adapter will always map to the lowest index valued
224 * device node. If vty-servers were hotplug removed from the system and then
225 * new ones added the new vty-server may have the largest slot number of all
226 * the vty-server adapters in the partition but it may have the lowest dev node
227 * index of all the adapters due to the hole left by the hotplug removed
228 * adapter. There are a set of functions provided to get the lowest index for
229 * a new device as well as return the index to the list. This list is allocated
230 * with a number of elements equal to the number of device nodes requested when
231 * the module was inserted.
233 static int *hvcs_index_list
;
236 * How large is the list? This is kept for traversal since the list is
237 * dynamically created.
239 static int hvcs_index_count
;
242 * Used by the khvcsd to pick up I/O operations when the kernel_thread is
243 * already awake but potentially shifted to TASK_INTERRUPTIBLE state.
245 static int hvcs_kicked
;
248 * Use by the kthread construct for task operations like waking the sleeping
249 * thread and stopping the kthread.
251 static struct task_struct
*hvcs_task
;
254 * We allocate this for the use of all of the hvcs_structs when they fetch
257 static unsigned long *hvcs_pi_buff
;
259 /* Only allow one hvcs_struct to use the hvcs_pi_buff at a time. */
260 static DEFINE_SPINLOCK(hvcs_pi_lock
);
262 /* One vty-server per hvcs_struct */
267 * This index identifies this hvcs device as the complement to a
268 * specific tty index.
272 struct tty_struct
*tty
;
273 unsigned int open_count
;
276 * Used to tell the driver kernel_thread what operations need to take
277 * place upon this hvcs_struct instance.
282 * This buffer is required so that when hvcs_write_room() reports that
283 * it can send HVCS_BUFF_LEN characters that it will buffer the full
284 * HVCS_BUFF_LEN characters if need be. This is essential for opost
285 * writes since they do not do high level buffering and expect to be
286 * able to send what the driver commits to sending buffering
287 * [e.g. tab to space conversions in n_tty.c opost()].
289 char buffer
[HVCS_BUFF_LEN
];
293 * Any variable below the kobject is valid before a tty is connected and
294 * stays valid after the tty is disconnected. These shouldn't be
295 * whacked until the koject refcount reaches zero though some entries
296 * may be changed via sysfs initiatives.
298 struct kobject kobj
; /* ref count & hvcs_struct lifetime */
299 int connected
; /* is the vty-server currently connected to a vty? */
300 uint32_t p_unit_address
; /* partner unit address */
301 uint32_t p_partition_ID
; /* partner partition ID */
302 char p_location_code
[HVCS_CLC_LENGTH
+ 1]; /* CLC + Null Term */
303 struct list_head next
; /* list management */
304 struct vio_dev
*vdev
;
307 /* Required to back map a kobject to its containing object */
308 #define from_kobj(kobj) container_of(kobj, struct hvcs_struct, kobj)
310 static struct list_head hvcs_structs
= LIST_HEAD_INIT(hvcs_structs
);
311 static DEFINE_SPINLOCK(hvcs_structs_lock
);
313 static void hvcs_unthrottle(struct tty_struct
*tty
);
314 static void hvcs_throttle(struct tty_struct
*tty
);
315 static irqreturn_t
hvcs_handle_interrupt(int irq
, void *dev_instance
,
316 struct pt_regs
*regs
);
318 static int hvcs_write(struct tty_struct
*tty
,
319 const unsigned char *buf
, int count
);
320 static int hvcs_write_room(struct tty_struct
*tty
);
321 static int hvcs_chars_in_buffer(struct tty_struct
*tty
);
323 static int hvcs_has_pi(struct hvcs_struct
*hvcsd
);
324 static void hvcs_set_pi(struct hvcs_partner_info
*pi
,
325 struct hvcs_struct
*hvcsd
);
326 static int hvcs_get_pi(struct hvcs_struct
*hvcsd
);
327 static int hvcs_rescan_devices_list(void);
329 static int hvcs_partner_connect(struct hvcs_struct
*hvcsd
);
330 static void hvcs_partner_free(struct hvcs_struct
*hvcsd
);
332 static int hvcs_enable_device(struct hvcs_struct
*hvcsd
,
333 uint32_t unit_address
, unsigned int irq
, struct vio_dev
*dev
);
335 static void destroy_hvcs_struct(struct kobject
*kobj
);
336 static int hvcs_open(struct tty_struct
*tty
, struct file
*filp
);
337 static void hvcs_close(struct tty_struct
*tty
, struct file
*filp
);
338 static void hvcs_hangup(struct tty_struct
* tty
);
340 static void hvcs_create_device_attrs(struct hvcs_struct
*hvcsd
);
341 static void hvcs_remove_device_attrs(struct vio_dev
*vdev
);
342 static void hvcs_create_driver_attrs(void);
343 static void hvcs_remove_driver_attrs(void);
345 static int __devinit
hvcs_probe(struct vio_dev
*dev
,
346 const struct vio_device_id
*id
);
347 static int __devexit
hvcs_remove(struct vio_dev
*dev
);
348 static int __init
hvcs_module_init(void);
349 static void __exit
hvcs_module_exit(void);
351 #define HVCS_SCHED_READ 0x00000001
352 #define HVCS_QUICK_READ 0x00000002
353 #define HVCS_TRY_WRITE 0x00000004
354 #define HVCS_READ_MASK (HVCS_SCHED_READ | HVCS_QUICK_READ)
356 static void hvcs_kick(void)
360 wake_up_process(hvcs_task
);
363 static void hvcs_unthrottle(struct tty_struct
*tty
)
365 struct hvcs_struct
*hvcsd
= tty
->driver_data
;
368 spin_lock_irqsave(&hvcsd
->lock
, flags
);
369 hvcsd
->todo_mask
|= HVCS_SCHED_READ
;
370 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
374 static void hvcs_throttle(struct tty_struct
*tty
)
376 struct hvcs_struct
*hvcsd
= tty
->driver_data
;
379 spin_lock_irqsave(&hvcsd
->lock
, flags
);
380 vio_disable_interrupts(hvcsd
->vdev
);
381 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
385 * If the device is being removed we don't have to worry about this interrupt
386 * handler taking any further interrupts because they are disabled which means
387 * the hvcs_struct will always be valid in this handler.
389 static irqreturn_t
hvcs_handle_interrupt(int irq
, void *dev_instance
,
390 struct pt_regs
*regs
)
392 struct hvcs_struct
*hvcsd
= dev_instance
;
394 spin_lock(&hvcsd
->lock
);
395 vio_disable_interrupts(hvcsd
->vdev
);
396 hvcsd
->todo_mask
|= HVCS_SCHED_READ
;
397 spin_unlock(&hvcsd
->lock
);
403 /* This function must be called with the hvcsd->lock held */
404 static void hvcs_try_write(struct hvcs_struct
*hvcsd
)
406 uint32_t unit_address
= hvcsd
->vdev
->unit_address
;
407 struct tty_struct
*tty
= hvcsd
->tty
;
410 if (hvcsd
->todo_mask
& HVCS_TRY_WRITE
) {
411 /* won't send partial writes */
412 sent
= hvc_put_chars(unit_address
,
414 hvcsd
->chars_in_buffer
);
416 hvcsd
->chars_in_buffer
= 0;
418 hvcsd
->todo_mask
&= ~(HVCS_TRY_WRITE
);
422 * We are still obligated to deliver the data to the
423 * hypervisor even if the tty has been closed because
424 * we commited to delivering it. But don't try to wake
425 * a non-existent tty.
434 static int hvcs_io(struct hvcs_struct
*hvcsd
)
436 uint32_t unit_address
;
437 struct tty_struct
*tty
;
438 char buf
[HVCS_BUFF_LEN
] __ALIGNED__
;
443 spin_lock_irqsave(&hvcsd
->lock
, flags
);
445 unit_address
= hvcsd
->vdev
->unit_address
;
448 hvcs_try_write(hvcsd
);
450 if (!tty
|| test_bit(TTY_THROTTLED
, &tty
->flags
)) {
451 hvcsd
->todo_mask
&= ~(HVCS_READ_MASK
);
453 } else if (!(hvcsd
->todo_mask
& (HVCS_READ_MASK
)))
456 /* remove the read masks */
457 hvcsd
->todo_mask
&= ~(HVCS_READ_MASK
);
459 if ((tty
->flip
.count
+ HVCS_BUFF_LEN
) < TTY_FLIPBUF_SIZE
) {
460 got
= hvc_get_chars(unit_address
,
463 for (i
=0;got
&& i
<got
;i
++)
464 tty_insert_flip_char(tty
, buf
[i
], TTY_NORMAL
);
467 /* Give the TTY time to process the data we just sent. */
469 hvcsd
->todo_mask
|= HVCS_QUICK_READ
;
471 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
472 if (tty
->flip
.count
) {
473 /* This is synch because tty->low_latency == 1 */
474 tty_flip_buffer_push(tty
);
478 /* Do this _after_ the flip_buffer_push */
479 spin_lock_irqsave(&hvcsd
->lock
, flags
);
480 vio_enable_interrupts(hvcsd
->vdev
);
481 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
484 return hvcsd
->todo_mask
;
487 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
488 return hvcsd
->todo_mask
;
491 static int khvcsd(void *unused
)
493 struct hvcs_struct
*hvcsd
;
496 __set_current_state(TASK_RUNNING
);
503 spin_lock(&hvcs_structs_lock
);
504 list_for_each_entry(hvcsd
, &hvcs_structs
, next
) {
505 hvcs_todo_mask
|= hvcs_io(hvcsd
);
507 spin_unlock(&hvcs_structs_lock
);
510 * If any of the hvcs adapters want to try a write or quick read
511 * don't schedule(), yield a smidgen then execute the hvcs_io
512 * thread again for those that want the write.
514 if (hvcs_todo_mask
& (HVCS_TRY_WRITE
| HVCS_QUICK_READ
)) {
519 set_current_state(TASK_INTERRUPTIBLE
);
522 __set_current_state(TASK_RUNNING
);
523 } while (!kthread_should_stop());
528 static struct vio_device_id hvcs_driver_table
[] __devinitdata
= {
529 {"serial-server", "hvterm2"},
532 MODULE_DEVICE_TABLE(vio
, hvcs_driver_table
);
534 static void hvcs_return_index(int index
)
537 if (!hvcs_index_list
)
539 if (index
< 0 || index
>= hvcs_index_count
)
541 if (hvcs_index_list
[index
] == -1)
544 hvcs_index_list
[index
] = -1;
547 /* callback when the kboject ref count reaches zero */
548 static void destroy_hvcs_struct(struct kobject
*kobj
)
550 struct hvcs_struct
*hvcsd
= from_kobj(kobj
);
551 struct vio_dev
*vdev
;
554 spin_lock(&hvcs_structs_lock
);
555 spin_lock_irqsave(&hvcsd
->lock
, flags
);
557 /* the list_del poisons the pointers */
558 list_del(&(hvcsd
->next
));
560 if (hvcsd
->connected
== 1) {
561 hvcs_partner_free(hvcsd
);
562 printk(KERN_INFO
"HVCS: Closed vty-server@%X and"
563 " partner vty@%X:%d connection.\n",
564 hvcsd
->vdev
->unit_address
,
565 hvcsd
->p_unit_address
,
566 (uint32_t)hvcsd
->p_partition_ID
);
568 printk(KERN_INFO
"HVCS: Destroyed hvcs_struct for vty-server@%X.\n",
569 hvcsd
->vdev
->unit_address
);
574 hvcsd
->p_unit_address
= 0;
575 hvcsd
->p_partition_ID
= 0;
576 hvcs_return_index(hvcsd
->index
);
577 memset(&hvcsd
->p_location_code
[0], 0x00, HVCS_CLC_LENGTH
+ 1);
579 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
580 spin_unlock(&hvcs_structs_lock
);
582 hvcs_remove_device_attrs(vdev
);
587 static struct kobj_type hvcs_kobj_type
= {
588 .release
= destroy_hvcs_struct
,
591 static int hvcs_get_index(void)
595 if (!hvcs_index_list
) {
596 printk(KERN_ERR
"HVCS: hvcs_index_list NOT valid!.\n");
599 /* Find the numerically lowest first free index. */
600 for(i
= 0; i
< hvcs_index_count
; i
++) {
601 if (hvcs_index_list
[i
] == -1) {
602 hvcs_index_list
[i
] = 0;
609 static int __devinit
hvcs_probe(
611 const struct vio_device_id
*id
)
613 struct hvcs_struct
*hvcsd
;
617 printk(KERN_ERR
"HVCS: probed with invalid parameter.\n");
621 /* early to avoid cleanup on failure */
622 index
= hvcs_get_index();
627 hvcsd
= kmalloc(sizeof(*hvcsd
), GFP_KERNEL
);
631 /* hvcsd->tty is zeroed out with the memset */
632 memset(hvcsd
, 0x00, sizeof(*hvcsd
));
634 spin_lock_init(&hvcsd
->lock
);
635 /* Automatically incs the refcount the first time */
636 kobject_init(&hvcsd
->kobj
);
637 /* Set up the callback for terminating the hvcs_struct's life */
638 hvcsd
->kobj
.ktype
= &hvcs_kobj_type
;
641 dev
->dev
.driver_data
= hvcsd
;
643 hvcsd
->index
= index
;
645 /* hvcsd->index = ++hvcs_struct_count; */
646 hvcsd
->chars_in_buffer
= 0;
647 hvcsd
->todo_mask
= 0;
648 hvcsd
->connected
= 0;
651 * This will populate the hvcs_struct's partner info fields for the
654 if (hvcs_get_pi(hvcsd
)) {
655 printk(KERN_ERR
"HVCS: Failed to fetch partner"
656 " info for vty-server@%X on device probe.\n",
657 hvcsd
->vdev
->unit_address
);
661 * If a user app opens a tty that corresponds to this vty-server before
662 * the hvcs_struct has been added to the devices list then the user app
666 spin_lock(&hvcs_structs_lock
);
668 list_add_tail(&(hvcsd
->next
), &hvcs_structs
);
670 spin_unlock(&hvcs_structs_lock
);
672 hvcs_create_device_attrs(hvcsd
);
674 printk(KERN_INFO
"HVCS: vty-server@%X added to the vio bus.\n", dev
->unit_address
);
677 * DON'T enable interrupts here because there is no user to receive the
683 static int __devexit
hvcs_remove(struct vio_dev
*dev
)
685 struct hvcs_struct
*hvcsd
= dev
->dev
.driver_data
;
687 struct kobject
*kobjp
;
688 struct tty_struct
*tty
;
693 /* By this time the vty-server won't be getting any more interrups */
695 spin_lock_irqsave(&hvcsd
->lock
, flags
);
699 kobjp
= &hvcsd
->kobj
;
701 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
704 * Let the last holder of this object cause it to be removed, which
705 * would probably be tty_hangup below.
710 * The hangup is a scheduled function which will auto chain call
711 * hvcs_hangup. The tty should always be valid at this time unless a
712 * simultaneous tty close already cleaned up the hvcs_struct.
717 printk(KERN_INFO
"HVCS: vty-server@%X removed from the"
718 " vio bus.\n", dev
->unit_address
);
722 static struct vio_driver hvcs_vio_driver
= {
723 .id_table
= hvcs_driver_table
,
725 .remove
= hvcs_remove
,
727 .name
= hvcs_driver_name
,
731 /* Only called from hvcs_get_pi please */
732 static void hvcs_set_pi(struct hvcs_partner_info
*pi
, struct hvcs_struct
*hvcsd
)
736 hvcsd
->p_unit_address
= pi
->unit_address
;
737 hvcsd
->p_partition_ID
= pi
->partition_ID
;
738 clclength
= strlen(&pi
->location_code
[0]);
739 if (clclength
> HVCS_CLC_LENGTH
)
740 clclength
= HVCS_CLC_LENGTH
;
742 /* copy the null-term char too */
743 strncpy(&hvcsd
->p_location_code
[0],
744 &pi
->location_code
[0], clclength
+ 1);
748 * Traverse the list and add the partner info that is found to the hvcs_struct
749 * struct entry. NOTE: At this time I know that partner info will return a
750 * single entry but in the future there may be multiple partner info entries per
751 * vty-server and you'll want to zero out that list and reset it. If for some
752 * reason you have an old version of this driver but there IS more than one
753 * partner info then hvcsd->p_* will hold the last partner info data from the
754 * firmware query. A good way to update this code would be to replace the three
755 * partner info fields in hvcs_struct with a list of hvcs_partner_info
758 * This function must be called with the hvcsd->lock held.
760 static int hvcs_get_pi(struct hvcs_struct
*hvcsd
)
762 struct hvcs_partner_info
*pi
;
763 uint32_t unit_address
= hvcsd
->vdev
->unit_address
;
764 struct list_head head
;
767 spin_lock(&hvcs_pi_lock
);
769 spin_unlock(&hvcs_pi_lock
);
772 retval
= hvcs_get_partner_info(unit_address
, &head
, hvcs_pi_buff
);
773 spin_unlock(&hvcs_pi_lock
);
775 printk(KERN_ERR
"HVCS: Failed to fetch partner"
776 " info for vty-server@%x.\n", unit_address
);
780 /* nixes the values if the partner vty went away */
781 hvcsd
->p_unit_address
= 0;
782 hvcsd
->p_partition_ID
= 0;
784 list_for_each_entry(pi
, &head
, node
)
785 hvcs_set_pi(pi
, hvcsd
);
787 hvcs_free_partner_info(&head
);
792 * This function is executed by the driver "rescan" sysfs entry. It shouldn't
793 * be executed elsewhere, in order to prevent deadlock issues.
795 static int hvcs_rescan_devices_list(void)
797 struct hvcs_struct
*hvcsd
;
800 spin_lock(&hvcs_structs_lock
);
802 list_for_each_entry(hvcsd
, &hvcs_structs
, next
) {
803 spin_lock_irqsave(&hvcsd
->lock
, flags
);
805 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
808 spin_unlock(&hvcs_structs_lock
);
814 * Farm this off into its own function because it could be more complex once
815 * multiple partners support is added. This function should be called with
816 * the hvcsd->lock held.
818 static int hvcs_has_pi(struct hvcs_struct
*hvcsd
)
820 if ((!hvcsd
->p_unit_address
) || (!hvcsd
->p_partition_ID
))
826 * NOTE: It is possible that the super admin removed a partner vty and then
827 * added a different vty as the new partner.
829 * This function must be called with the hvcsd->lock held.
831 static int hvcs_partner_connect(struct hvcs_struct
*hvcsd
)
834 unsigned int unit_address
= hvcsd
->vdev
->unit_address
;
837 * If there wasn't any pi when the device was added it doesn't meant
838 * there isn't any now. This driver isn't notified when a new partner
839 * vty is added to a vty-server so we discover changes on our own.
840 * Please see comments in hvcs_register_connection() for justification
841 * of this bizarre code.
843 retval
= hvcs_register_connection(unit_address
,
844 hvcsd
->p_partition_ID
,
845 hvcsd
->p_unit_address
);
847 hvcsd
->connected
= 1;
849 } else if (retval
!= -EINVAL
)
853 * As per the spec re-get the pi and try again if -EINVAL after the
854 * first connection attempt.
856 if (hvcs_get_pi(hvcsd
))
859 if (!hvcs_has_pi(hvcsd
))
862 retval
= hvcs_register_connection(unit_address
,
863 hvcsd
->p_partition_ID
,
864 hvcsd
->p_unit_address
);
865 if (retval
!= -EINVAL
) {
866 hvcsd
->connected
= 1;
871 * EBUSY is the most likely scenario though the vty could have been
872 * removed or there really could be an hcall error due to the parameter
873 * data but thanks to ambiguous firmware return codes we can't really
876 printk(KERN_INFO
"HVCS: vty-server or partner"
877 " vty is busy. Try again later.\n");
881 /* This function must be called with the hvcsd->lock held */
882 static void hvcs_partner_free(struct hvcs_struct
*hvcsd
)
886 retval
= hvcs_free_connection(hvcsd
->vdev
->unit_address
);
887 } while (retval
== -EBUSY
);
888 hvcsd
->connected
= 0;
891 /* This helper function must be called WITHOUT the hvcsd->lock held */
892 static int hvcs_enable_device(struct hvcs_struct
*hvcsd
, uint32_t unit_address
,
893 unsigned int irq
, struct vio_dev
*vdev
)
899 * It is possible that the vty-server was removed between the time that
900 * the conn was registered and now.
902 if (!(rc
= request_irq(irq
, &hvcs_handle_interrupt
,
903 SA_INTERRUPT
, "ibmhvcs", hvcsd
))) {
905 * It is possible the vty-server was removed after the irq was
906 * requested but before we have time to enable interrupts.
908 if (vio_enable_interrupts(vdev
) == H_Success
)
911 printk(KERN_ERR
"HVCS: int enable failed for"
912 " vty-server@%X.\n", unit_address
);
913 free_irq(irq
, hvcsd
);
916 printk(KERN_ERR
"HVCS: irq req failed for"
917 " vty-server@%X.\n", unit_address
);
919 spin_lock_irqsave(&hvcsd
->lock
, flags
);
920 hvcs_partner_free(hvcsd
);
921 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
928 * This always increments the kobject ref count if the call is successful.
929 * Please remember to dec when you are done with the instance.
931 * NOTICE: Do NOT hold either the hvcs_struct.lock or hvcs_structs_lock when
932 * calling this function or you will get deadlock.
934 struct hvcs_struct
*hvcs_get_by_index(int index
)
936 struct hvcs_struct
*hvcsd
= NULL
;
939 spin_lock(&hvcs_structs_lock
);
940 /* We can immediately discard OOB requests */
941 if (index
>= 0 && index
< HVCS_MAX_SERVER_ADAPTERS
) {
942 list_for_each_entry(hvcsd
, &hvcs_structs
, next
) {
943 spin_lock_irqsave(&hvcsd
->lock
, flags
);
944 if (hvcsd
->index
== index
) {
945 kobject_get(&hvcsd
->kobj
);
946 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
947 spin_unlock(&hvcs_structs_lock
);
950 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
955 spin_unlock(&hvcs_structs_lock
);
960 * This is invoked via the tty_open interface when a user app connects to the
963 static int hvcs_open(struct tty_struct
*tty
, struct file
*filp
)
965 struct hvcs_struct
*hvcsd
;
969 struct vio_dev
*vdev
;
970 unsigned long unit_address
;
971 struct kobject
*kobjp
;
973 if (tty
->driver_data
)
977 * Is there a vty-server that shares the same index?
978 * This function increments the kobject index.
980 if (!(hvcsd
= hvcs_get_by_index(tty
->index
))) {
981 printk(KERN_WARNING
"HVCS: open failed, no device associated"
982 " with tty->index %d.\n", tty
->index
);
986 spin_lock_irqsave(&hvcsd
->lock
, flags
);
988 if (hvcsd
->connected
== 0)
989 if ((retval
= hvcs_partner_connect(hvcsd
)))
992 hvcsd
->open_count
= 1;
994 tty
->driver_data
= hvcsd
;
997 * Set this driver to low latency so that we actually have a chance at
998 * catching a throttled TTY after we flip_buffer_push. Otherwise the
999 * flush_to_async may not execute until after the kernel_thread has
1000 * yielded and resumed the next flip_buffer_push resulting in data
1003 tty
->low_latency
= 1;
1005 memset(&hvcsd
->buffer
[0], 0x00, HVCS_BUFF_LEN
);
1008 * Save these in the spinlock for the enable operations that need them
1009 * outside of the spinlock.
1011 irq
= hvcsd
->vdev
->irq
;
1013 unit_address
= hvcsd
->vdev
->unit_address
;
1015 hvcsd
->todo_mask
|= HVCS_SCHED_READ
;
1016 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1019 * This must be done outside of the spinlock because it requests irqs
1020 * and will grab the spinlock and free the connection if it fails.
1022 if (((rc
= hvcs_enable_device(hvcsd
, unit_address
, irq
, vdev
)))) {
1023 kobject_put(&hvcsd
->kobj
);
1024 printk(KERN_WARNING
"HVCS: enable device failed.\n");
1031 hvcsd
= tty
->driver_data
;
1033 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1034 if (!kobject_get(&hvcsd
->kobj
)) {
1035 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1036 printk(KERN_ERR
"HVCS: Kobject of open"
1037 " hvcs doesn't exist.\n");
1038 return -EFAULT
; /* Is this the right return value? */
1041 hvcsd
->open_count
++;
1043 hvcsd
->todo_mask
|= HVCS_SCHED_READ
;
1044 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1048 printk(KERN_INFO
"HVCS: vty-server@%X connection opened.\n",
1049 hvcsd
->vdev
->unit_address
);
1054 kobjp
= &hvcsd
->kobj
;
1055 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1056 kobject_put(&hvcsd
->kobj
);
1058 printk(KERN_WARNING
"HVCS: partner connect failed.\n");
1062 static void hvcs_close(struct tty_struct
*tty
, struct file
*filp
)
1064 struct hvcs_struct
*hvcsd
;
1065 unsigned long flags
;
1066 struct kobject
*kobjp
;
1070 * Is someone trying to close the file associated with this device after
1071 * we have hung up? If so tty->driver_data wouldn't be valid.
1073 if (tty_hung_up_p(filp
))
1077 * No driver_data means that this close was probably issued after a
1078 * failed hvcs_open by the tty layer's release_dev() api and we can just
1081 if (!tty
->driver_data
)
1084 hvcsd
= tty
->driver_data
;
1086 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1087 kobjp
= &hvcsd
->kobj
;
1088 if (--hvcsd
->open_count
== 0) {
1090 vio_disable_interrupts(hvcsd
->vdev
);
1093 * NULL this early so that the kernel_thread doesn't try to
1094 * execute any operations on the TTY even though it is obligated
1095 * to deliver any pending I/O to the hypervisor.
1099 irq
= hvcsd
->vdev
->irq
;
1100 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1102 tty_wait_until_sent(tty
, HVCS_CLOSE_WAIT
);
1105 * This line is important because it tells hvcs_open that this
1106 * device needs to be re-configured the next time hvcs_open is
1109 tty
->driver_data
= NULL
;
1111 free_irq(irq
, hvcsd
);
1114 } else if (hvcsd
->open_count
< 0) {
1115 printk(KERN_ERR
"HVCS: vty-server@%X open_count: %d"
1116 " is missmanaged.\n",
1117 hvcsd
->vdev
->unit_address
, hvcsd
->open_count
);
1120 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1124 static void hvcs_hangup(struct tty_struct
* tty
)
1126 struct hvcs_struct
*hvcsd
= tty
->driver_data
;
1127 unsigned long flags
;
1128 int temp_open_count
;
1129 struct kobject
*kobjp
;
1132 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1133 /* Preserve this so that we know how many kobject refs to put */
1134 temp_open_count
= hvcsd
->open_count
;
1137 * Don't kobject put inside the spinlock because the destruction
1138 * callback may use the spinlock and it may get called before the
1139 * spinlock has been released. Get a pointer to the kobject and
1140 * kobject_put on that after releasing the spinlock.
1142 kobjp
= &hvcsd
->kobj
;
1144 vio_disable_interrupts(hvcsd
->vdev
);
1146 hvcsd
->todo_mask
= 0;
1148 /* I don't think the tty needs the hvcs_struct pointer after a hangup */
1149 hvcsd
->tty
->driver_data
= NULL
;
1152 hvcsd
->open_count
= 0;
1154 /* This will drop any buffered data on the floor which is OK in a hangup
1156 memset(&hvcsd
->buffer
[0], 0x00, HVCS_BUFF_LEN
);
1157 hvcsd
->chars_in_buffer
= 0;
1159 irq
= hvcsd
->vdev
->irq
;
1161 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1163 free_irq(irq
, hvcsd
);
1166 * We need to kobject_put() for every open_count we have since the
1167 * tty_hangup() function doesn't invoke a close per open connection on a
1168 * non-console device.
1170 while(temp_open_count
) {
1173 * The final put will trigger destruction of the hvcs_struct.
1174 * NOTE: If this hangup was signaled from user space then the
1175 * final put will never happen.
1182 * NOTE: This is almost always from_user since user level apps interact with the
1183 * /dev nodes. I'm trusting that if hvcs_write gets called and interrupted by
1184 * hvcs_remove (which removes the target device and executes tty_hangup()) that
1185 * tty_hangup will allow hvcs_write time to complete execution before it
1186 * terminates our device.
1188 static int hvcs_write(struct tty_struct
*tty
,
1189 const unsigned char *buf
, int count
)
1191 struct hvcs_struct
*hvcsd
= tty
->driver_data
;
1192 unsigned int unit_address
;
1193 const unsigned char *charbuf
;
1194 unsigned long flags
;
1200 * If they don't check the return code off of their open they may
1201 * attempt this even if there is no connected device.
1206 /* Reasonable size to prevent user level flooding */
1207 if (count
> HVCS_MAX_FROM_USER
) {
1208 printk(KERN_WARNING
"HVCS write: count being truncated to"
1209 " HVCS_MAX_FROM_USER.\n");
1210 count
= HVCS_MAX_FROM_USER
;
1215 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1218 * Somehow an open succedded but the device was removed or the
1219 * connection terminated between the vty-server and partner vty during
1220 * the middle of a write operation? This is a crummy place to do this
1221 * but we want to keep it all in the spinlock.
1223 if (hvcsd
->open_count
<= 0) {
1224 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1228 unit_address
= hvcsd
->vdev
->unit_address
;
1231 tosend
= min(count
, (HVCS_BUFF_LEN
- hvcsd
->chars_in_buffer
));
1233 * No more space, this probably means that the last call to
1234 * hvcs_write() didn't succeed and the buffer was filled up.
1239 memcpy(&hvcsd
->buffer
[hvcsd
->chars_in_buffer
],
1240 &charbuf
[total_sent
],
1243 hvcsd
->chars_in_buffer
+= tosend
;
1248 * If this is true then we don't want to try writing to the
1249 * hypervisor because that is the kernel_threads job now. We'll
1250 * just add to the buffer.
1252 if (!(hvcsd
->todo_mask
& HVCS_TRY_WRITE
))
1253 /* won't send partial writes */
1254 result
= hvc_put_chars(unit_address
,
1256 hvcsd
->chars_in_buffer
);
1259 * Since we know we have enough room in hvcsd->buffer for
1260 * tosend we record that it was sent regardless of whether the
1261 * hypervisor actually took it because we have it buffered.
1266 hvcsd
->todo_mask
|= HVCS_TRY_WRITE
;
1271 hvcsd
->chars_in_buffer
= 0;
1273 * Test after the chars_in_buffer reset otherwise this could
1274 * deadlock our writes if hvc_put_chars fails.
1280 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1289 * This is really asking how much can we guarentee that we can send or that we
1290 * absolutely WILL BUFFER if we can't send it. This driver MUST honor the
1291 * return value, hence the reason for hvcs_struct buffering.
1293 static int hvcs_write_room(struct tty_struct
*tty
)
1295 struct hvcs_struct
*hvcsd
= tty
->driver_data
;
1297 if (!hvcsd
|| hvcsd
->open_count
<= 0)
1300 return HVCS_BUFF_LEN
- hvcsd
->chars_in_buffer
;
1303 static int hvcs_chars_in_buffer(struct tty_struct
*tty
)
1305 struct hvcs_struct
*hvcsd
= tty
->driver_data
;
1307 return hvcsd
->chars_in_buffer
;
1310 static struct tty_operations hvcs_ops
= {
1312 .close
= hvcs_close
,
1313 .hangup
= hvcs_hangup
,
1314 .write
= hvcs_write
,
1315 .write_room
= hvcs_write_room
,
1316 .chars_in_buffer
= hvcs_chars_in_buffer
,
1317 .unthrottle
= hvcs_unthrottle
,
1318 .throttle
= hvcs_throttle
,
1321 static int hvcs_alloc_index_list(int n
)
1324 hvcs_index_list
= kmalloc(n
* sizeof(hvcs_index_count
),GFP_KERNEL
);
1325 if (!hvcs_index_list
)
1327 hvcs_index_count
= n
;
1328 for(i
= 0; i
< hvcs_index_count
; i
++)
1329 hvcs_index_list
[i
] = -1;
1333 static void hvcs_free_index_list(void)
1335 /* Paranoia check to be thorough. */
1336 if (hvcs_index_list
) {
1337 kfree(hvcs_index_list
);
1338 hvcs_index_list
= NULL
;
1339 hvcs_index_count
= 0;
1343 static int __init
hvcs_module_init(void)
1346 int num_ttys_to_alloc
;
1348 printk(KERN_INFO
"Initializing %s\n", hvcs_driver_string
);
1350 /* Has the user specified an overload with an insmod param? */
1351 if (hvcs_parm_num_devs
<= 0 ||
1352 (hvcs_parm_num_devs
> HVCS_MAX_SERVER_ADAPTERS
)) {
1353 num_ttys_to_alloc
= HVCS_DEFAULT_SERVER_ADAPTERS
;
1355 num_ttys_to_alloc
= hvcs_parm_num_devs
;
1357 hvcs_tty_driver
= alloc_tty_driver(num_ttys_to_alloc
);
1358 if (!hvcs_tty_driver
)
1361 if (hvcs_alloc_index_list(num_ttys_to_alloc
))
1364 hvcs_tty_driver
->owner
= THIS_MODULE
;
1366 hvcs_tty_driver
->driver_name
= hvcs_driver_name
;
1367 hvcs_tty_driver
->name
= hvcs_device_node
;
1368 hvcs_tty_driver
->devfs_name
= hvcs_device_node
;
1371 * We'll let the system assign us a major number, indicated by leaving
1375 hvcs_tty_driver
->minor_start
= HVCS_MINOR_START
;
1376 hvcs_tty_driver
->type
= TTY_DRIVER_TYPE_SYSTEM
;
1379 * We role our own so that we DONT ECHO. We can't echo because the
1380 * device we are connecting to already echoes by default and this would
1381 * throw us into a horrible recursive echo-echo-echo loop.
1383 hvcs_tty_driver
->init_termios
= hvcs_tty_termios
;
1384 hvcs_tty_driver
->flags
= TTY_DRIVER_REAL_RAW
;
1386 tty_set_operations(hvcs_tty_driver
, &hvcs_ops
);
1389 * The following call will result in sysfs entries that denote the
1390 * dynamically assigned major and minor numbers for our devices.
1392 if (tty_register_driver(hvcs_tty_driver
)) {
1393 printk(KERN_ERR
"HVCS: registration "
1394 " as a tty driver failed.\n");
1395 hvcs_free_index_list();
1396 put_tty_driver(hvcs_tty_driver
);
1400 hvcs_pi_buff
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
1401 if (!hvcs_pi_buff
) {
1402 tty_unregister_driver(hvcs_tty_driver
);
1403 hvcs_free_index_list();
1404 put_tty_driver(hvcs_tty_driver
);
1408 hvcs_task
= kthread_run(khvcsd
, NULL
, "khvcsd");
1409 if (IS_ERR(hvcs_task
)) {
1410 printk(KERN_ERR
"HVCS: khvcsd creation failed. Driver not loaded.\n");
1411 kfree(hvcs_pi_buff
);
1412 tty_unregister_driver(hvcs_tty_driver
);
1413 hvcs_free_index_list();
1414 put_tty_driver(hvcs_tty_driver
);
1418 rc
= vio_register_driver(&hvcs_vio_driver
);
1421 * This needs to be done AFTER the vio_register_driver() call or else
1422 * the kobjects won't be initialized properly.
1424 hvcs_create_driver_attrs();
1426 printk(KERN_INFO
"HVCS: driver module inserted.\n");
1431 static void __exit
hvcs_module_exit(void)
1434 * This driver receives hvcs_remove callbacks for each device upon
1439 * This synchronous operation will wake the khvcsd kthread if it is
1440 * asleep and will return when khvcsd has terminated.
1442 kthread_stop(hvcs_task
);
1444 spin_lock(&hvcs_pi_lock
);
1445 kfree(hvcs_pi_buff
);
1446 hvcs_pi_buff
= NULL
;
1447 spin_unlock(&hvcs_pi_lock
);
1449 hvcs_remove_driver_attrs();
1451 vio_unregister_driver(&hvcs_vio_driver
);
1453 tty_unregister_driver(hvcs_tty_driver
);
1455 hvcs_free_index_list();
1457 put_tty_driver(hvcs_tty_driver
);
1459 printk(KERN_INFO
"HVCS: driver module removed.\n");
1462 module_init(hvcs_module_init
);
1463 module_exit(hvcs_module_exit
);
1465 static inline struct hvcs_struct
*from_vio_dev(struct vio_dev
*viod
)
1467 return viod
->dev
.driver_data
;
1469 /* The sysfs interface for the driver and devices */
1471 static ssize_t
hvcs_partner_vtys_show(struct device
*dev
, struct device_attribute
*attr
, char *buf
)
1473 struct vio_dev
*viod
= to_vio_dev(dev
);
1474 struct hvcs_struct
*hvcsd
= from_vio_dev(viod
);
1475 unsigned long flags
;
1478 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1479 retval
= sprintf(buf
, "%X\n", hvcsd
->p_unit_address
);
1480 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1483 static DEVICE_ATTR(partner_vtys
, S_IRUGO
, hvcs_partner_vtys_show
, NULL
);
1485 static ssize_t
hvcs_partner_clcs_show(struct device
*dev
, struct device_attribute
*attr
, char *buf
)
1487 struct vio_dev
*viod
= to_vio_dev(dev
);
1488 struct hvcs_struct
*hvcsd
= from_vio_dev(viod
);
1489 unsigned long flags
;
1492 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1493 retval
= sprintf(buf
, "%s\n", &hvcsd
->p_location_code
[0]);
1494 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1497 static DEVICE_ATTR(partner_clcs
, S_IRUGO
, hvcs_partner_clcs_show
, NULL
);
1499 static ssize_t
hvcs_current_vty_store(struct device
*dev
, struct device_attribute
*attr
, const char * buf
,
1503 * Don't need this feature at the present time because firmware doesn't
1504 * yet support multiple partners.
1506 printk(KERN_INFO
"HVCS: Denied current_vty change: -EPERM.\n");
1510 static ssize_t
hvcs_current_vty_show(struct device
*dev
, struct device_attribute
*attr
, char *buf
)
1512 struct vio_dev
*viod
= to_vio_dev(dev
);
1513 struct hvcs_struct
*hvcsd
= from_vio_dev(viod
);
1514 unsigned long flags
;
1517 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1518 retval
= sprintf(buf
, "%s\n", &hvcsd
->p_location_code
[0]);
1519 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1523 static DEVICE_ATTR(current_vty
,
1524 S_IRUGO
| S_IWUSR
, hvcs_current_vty_show
, hvcs_current_vty_store
);
1526 static ssize_t
hvcs_vterm_state_store(struct device
*dev
, struct device_attribute
*attr
, const char *buf
,
1529 struct vio_dev
*viod
= to_vio_dev(dev
);
1530 struct hvcs_struct
*hvcsd
= from_vio_dev(viod
);
1531 unsigned long flags
;
1533 /* writing a '0' to this sysfs entry will result in the disconnect. */
1534 if (simple_strtol(buf
, NULL
, 0) != 0)
1537 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1539 if (hvcsd
->open_count
> 0) {
1540 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1541 printk(KERN_INFO
"HVCS: vterm state unchanged. "
1542 "The hvcs device node is still in use.\n");
1546 if (hvcsd
->connected
== 0) {
1547 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1548 printk(KERN_INFO
"HVCS: vterm state unchanged. The"
1549 " vty-server is not connected to a vty.\n");
1553 hvcs_partner_free(hvcsd
);
1554 printk(KERN_INFO
"HVCS: Closed vty-server@%X and"
1555 " partner vty@%X:%d connection.\n",
1556 hvcsd
->vdev
->unit_address
,
1557 hvcsd
->p_unit_address
,
1558 (uint32_t)hvcsd
->p_partition_ID
);
1560 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1564 static ssize_t
hvcs_vterm_state_show(struct device
*dev
, struct device_attribute
*attr
, char *buf
)
1566 struct vio_dev
*viod
= to_vio_dev(dev
);
1567 struct hvcs_struct
*hvcsd
= from_vio_dev(viod
);
1568 unsigned long flags
;
1571 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1572 retval
= sprintf(buf
, "%d\n", hvcsd
->connected
);
1573 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1576 static DEVICE_ATTR(vterm_state
, S_IRUGO
| S_IWUSR
,
1577 hvcs_vterm_state_show
, hvcs_vterm_state_store
);
1579 static ssize_t
hvcs_index_show(struct device
*dev
, struct device_attribute
*attr
, char *buf
)
1581 struct vio_dev
*viod
= to_vio_dev(dev
);
1582 struct hvcs_struct
*hvcsd
= from_vio_dev(viod
);
1583 unsigned long flags
;
1586 spin_lock_irqsave(&hvcsd
->lock
, flags
);
1587 retval
= sprintf(buf
, "%d\n", hvcsd
->index
);
1588 spin_unlock_irqrestore(&hvcsd
->lock
, flags
);
1592 static DEVICE_ATTR(index
, S_IRUGO
, hvcs_index_show
, NULL
);
1594 static struct attribute
*hvcs_attrs
[] = {
1595 &dev_attr_partner_vtys
.attr
,
1596 &dev_attr_partner_clcs
.attr
,
1597 &dev_attr_current_vty
.attr
,
1598 &dev_attr_vterm_state
.attr
,
1599 &dev_attr_index
.attr
,
1603 static struct attribute_group hvcs_attr_group
= {
1604 .attrs
= hvcs_attrs
,
1607 static void hvcs_create_device_attrs(struct hvcs_struct
*hvcsd
)
1609 struct vio_dev
*vdev
= hvcsd
->vdev
;
1610 sysfs_create_group(&vdev
->dev
.kobj
, &hvcs_attr_group
);
1613 static void hvcs_remove_device_attrs(struct vio_dev
*vdev
)
1615 sysfs_remove_group(&vdev
->dev
.kobj
, &hvcs_attr_group
);
1618 static ssize_t
hvcs_rescan_show(struct device_driver
*ddp
, char *buf
)
1620 /* A 1 means it is updating, a 0 means it is done updating */
1621 return snprintf(buf
, PAGE_SIZE
, "%d\n", hvcs_rescan_status
);
1624 static ssize_t
hvcs_rescan_store(struct device_driver
*ddp
, const char * buf
,
1627 if ((simple_strtol(buf
, NULL
, 0) != 1)
1628 && (hvcs_rescan_status
!= 0))
1631 hvcs_rescan_status
= 1;
1632 printk(KERN_INFO
"HVCS: rescanning partner info for all"
1634 hvcs_rescan_devices_list();
1635 hvcs_rescan_status
= 0;
1638 static DRIVER_ATTR(rescan
,
1639 S_IRUGO
| S_IWUSR
, hvcs_rescan_show
, hvcs_rescan_store
);
1641 static void hvcs_create_driver_attrs(void)
1643 struct device_driver
*driverfs
= &(hvcs_vio_driver
.driver
);
1644 driver_create_file(driverfs
, &driver_attr_rescan
);
1647 static void hvcs_remove_driver_attrs(void)
1649 struct device_driver
*driverfs
= &(hvcs_vio_driver
.driver
);
1650 driver_remove_file(driverfs
, &driver_attr_rescan
);