2 * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
3 * Copyright (C) 2009, 2010, 2011 Red Hat, Inc.
4 * Copyright (C) 2009, 2010, 2011 Amit Shah <amit.shah@redhat.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 #include <linux/cdev.h>
21 #include <linux/debugfs.h>
22 #include <linux/completion.h>
23 #include <linux/device.h>
24 #include <linux/err.h>
25 #include <linux/freezer.h>
27 #include <linux/splice.h>
28 #include <linux/pagemap.h>
29 #include <linux/init.h>
30 #include <linux/list.h>
31 #include <linux/poll.h>
32 #include <linux/sched.h>
33 #include <linux/slab.h>
34 #include <linux/spinlock.h>
35 #include <linux/virtio.h>
36 #include <linux/virtio_console.h>
37 #include <linux/wait.h>
38 #include <linux/workqueue.h>
39 #include <linux/module.h>
40 #include "../tty/hvc/hvc_console.h"
43 * This is a global struct for storing common data for all the devices
44 * this driver handles.
46 * Mainly, it has a linked list for all the consoles in one place so
47 * that callbacks from hvc for get_chars(), put_chars() work properly
48 * across multiple devices and multiple ports per device.
50 struct ports_driver_data
{
51 /* Used for registering chardevs */
54 /* Used for exporting per-port information to debugfs */
55 struct dentry
*debugfs_dir
;
57 /* List of all the devices we're handling */
58 struct list_head portdevs
;
60 /* Number of devices this driver is handling */
64 * This is used to keep track of the number of hvc consoles
65 * spawned by this driver. This number is given as the first
66 * argument to hvc_alloc(). To correctly map an initial
67 * console spawned via hvc_instantiate to the console being
68 * hooked up via hvc_alloc, we need to pass the same vtermno.
70 * We also just assume the first console being initialised was
71 * the first one that got used as the initial console.
73 unsigned int next_vtermno
;
75 /* All the console devices handled by this driver */
76 struct list_head consoles
;
78 static struct ports_driver_data pdrvdata
;
80 DEFINE_SPINLOCK(pdrvdata_lock
);
81 DECLARE_COMPLETION(early_console_added
);
83 /* This struct holds information that's relevant only for console ports */
85 /* We'll place all consoles in a list in the pdrvdata struct */
86 struct list_head list
;
88 /* The hvc device associated with this console port */
89 struct hvc_struct
*hvc
;
91 /* The size of the console */
95 * This number identifies the number that we used to register
96 * with hvc in hvc_instantiate() and hvc_alloc(); this is the
97 * number passed on by the hvc callbacks to us to
98 * differentiate between the other console ports handled by
107 /* size of the buffer in *buf above */
110 /* used length of the buffer */
112 /* offset in the buf from which to consume data */
117 * This is a per-device struct that stores data common to all the
118 * ports for that device (vdev->priv).
120 struct ports_device
{
121 /* Next portdev in the list, head is in the pdrvdata struct */
122 struct list_head list
;
125 * Workqueue handlers where we process deferred work after
128 struct work_struct control_work
;
130 struct list_head ports
;
132 /* To protect the list of ports */
133 spinlock_t ports_lock
;
135 /* To protect the vq operations for the control channel */
138 /* The current config space is stored here */
139 struct virtio_console_config config
;
141 /* The virtio device we're associated with */
142 struct virtio_device
*vdev
;
145 * A couple of virtqueues for the control channel: one for
146 * guest->host transfers, one for host->guest transfers
148 struct virtqueue
*c_ivq
, *c_ovq
;
150 /* Array of per-port IO virtqueues */
151 struct virtqueue
**in_vqs
, **out_vqs
;
153 /* Used for numbering devices for sysfs and debugfs */
154 unsigned int drv_index
;
156 /* Major number for this device. Ports will be created as minors. */
161 unsigned long bytes_sent
, bytes_received
, bytes_discarded
;
164 /* This struct holds the per-port data */
166 /* Next port in the list, head is in the ports_device */
167 struct list_head list
;
169 /* Pointer to the parent virtio_console device */
170 struct ports_device
*portdev
;
172 /* The current buffer from which data has to be fed to readers */
173 struct port_buffer
*inbuf
;
176 * To protect the operations on the in_vq associated with this
177 * port. Has to be a spinlock because it can be called from
178 * interrupt context (get_char()).
180 spinlock_t inbuf_lock
;
182 /* Protect the operations on the out_vq. */
183 spinlock_t outvq_lock
;
185 /* The IO vqs for this port */
186 struct virtqueue
*in_vq
, *out_vq
;
188 /* File in the debugfs directory that exposes this port's information */
189 struct dentry
*debugfs_file
;
192 * Keep count of the bytes sent, received and discarded for
193 * this port for accounting and debugging purposes. These
194 * counts are not reset across port open / close events.
196 struct port_stats stats
;
199 * The entries in this struct will be valid if this port is
200 * hooked up to an hvc console
204 /* Each port associates with a separate char device */
208 /* Reference-counting to handle port hot-unplugs and file operations */
211 /* A waitqueue for poll() or blocking read operations */
212 wait_queue_head_t waitqueue
;
214 /* The 'name' of the port that we expose via sysfs properties */
217 /* We can notify apps of host connect / disconnect events via SIGIO */
218 struct fasync_struct
*async_queue
;
220 /* The 'id' to identify the port with the Host */
225 /* Is the host device open */
228 /* We should allow only one process to open a port */
229 bool guest_connected
;
232 /* This is the very early arch-specified put chars function. */
233 static int (*early_put_chars
)(u32
, const char *, int);
235 static struct port
*find_port_by_vtermno(u32 vtermno
)
238 struct console
*cons
;
241 spin_lock_irqsave(&pdrvdata_lock
, flags
);
242 list_for_each_entry(cons
, &pdrvdata
.consoles
, list
) {
243 if (cons
->vtermno
== vtermno
) {
244 port
= container_of(cons
, struct port
, cons
);
250 spin_unlock_irqrestore(&pdrvdata_lock
, flags
);
254 static struct port
*find_port_by_devt_in_portdev(struct ports_device
*portdev
,
260 spin_lock_irqsave(&portdev
->ports_lock
, flags
);
261 list_for_each_entry(port
, &portdev
->ports
, list
)
262 if (port
->cdev
->dev
== dev
)
266 spin_unlock_irqrestore(&portdev
->ports_lock
, flags
);
271 static struct port
*find_port_by_devt(dev_t dev
)
273 struct ports_device
*portdev
;
277 spin_lock_irqsave(&pdrvdata_lock
, flags
);
278 list_for_each_entry(portdev
, &pdrvdata
.portdevs
, list
) {
279 port
= find_port_by_devt_in_portdev(portdev
, dev
);
285 spin_unlock_irqrestore(&pdrvdata_lock
, flags
);
289 static struct port
*find_port_by_id(struct ports_device
*portdev
, u32 id
)
294 spin_lock_irqsave(&portdev
->ports_lock
, flags
);
295 list_for_each_entry(port
, &portdev
->ports
, list
)
300 spin_unlock_irqrestore(&portdev
->ports_lock
, flags
);
305 static struct port
*find_port_by_vq(struct ports_device
*portdev
,
306 struct virtqueue
*vq
)
311 spin_lock_irqsave(&portdev
->ports_lock
, flags
);
312 list_for_each_entry(port
, &portdev
->ports
, list
)
313 if (port
->in_vq
== vq
|| port
->out_vq
== vq
)
317 spin_unlock_irqrestore(&portdev
->ports_lock
, flags
);
321 static bool is_console_port(struct port
*port
)
328 static inline bool use_multiport(struct ports_device
*portdev
)
331 * This condition can be true when put_chars is called from
336 return portdev
->vdev
->features
[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT
);
339 static void free_buf(struct port_buffer
*buf
)
345 static struct port_buffer
*alloc_buf(size_t buf_size
)
347 struct port_buffer
*buf
;
349 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
352 buf
->buf
= kzalloc(buf_size
, GFP_KERNEL
);
357 buf
->size
= buf_size
;
366 /* Callers should take appropriate locks */
367 static struct port_buffer
*get_inbuf(struct port
*port
)
369 struct port_buffer
*buf
;
375 buf
= virtqueue_get_buf(port
->in_vq
, &len
);
379 port
->stats
.bytes_received
+= len
;
385 * Create a scatter-gather list representing our input buffer and put
388 * Callers should take appropriate locks.
390 static int add_inbuf(struct virtqueue
*vq
, struct port_buffer
*buf
)
392 struct scatterlist sg
[1];
395 sg_init_one(sg
, buf
->buf
, buf
->size
);
397 ret
= virtqueue_add_buf(vq
, sg
, 0, 1, buf
, GFP_ATOMIC
);
402 /* Discard any unread data this port has. Callers lockers. */
403 static void discard_port_data(struct port
*port
)
405 struct port_buffer
*buf
;
408 if (!port
->portdev
) {
409 /* Device has been unplugged. vqs are already gone. */
412 buf
= get_inbuf(port
);
416 port
->stats
.bytes_discarded
+= buf
->len
- buf
->offset
;
417 if (add_inbuf(port
->in_vq
, buf
) < 0) {
422 buf
= get_inbuf(port
);
425 dev_warn(port
->dev
, "Errors adding %d buffers back to vq\n",
429 static bool port_has_data(struct port
*port
)
435 spin_lock_irqsave(&port
->inbuf_lock
, flags
);
436 port
->inbuf
= get_inbuf(port
);
440 spin_unlock_irqrestore(&port
->inbuf_lock
, flags
);
444 static ssize_t
__send_control_msg(struct ports_device
*portdev
, u32 port_id
,
445 unsigned int event
, unsigned int value
)
447 struct scatterlist sg
[1];
448 struct virtio_console_control cpkt
;
449 struct virtqueue
*vq
;
452 if (!use_multiport(portdev
))
461 sg_init_one(sg
, &cpkt
, sizeof(cpkt
));
462 if (virtqueue_add_buf(vq
, sg
, 1, 0, &cpkt
, GFP_ATOMIC
) >= 0) {
464 while (!virtqueue_get_buf(vq
, &len
))
470 static ssize_t
send_control_msg(struct port
*port
, unsigned int event
,
473 /* Did the port get unplugged before userspace closed it? */
475 return __send_control_msg(port
->portdev
, port
->id
, event
, value
);
479 struct buffer_token
{
482 struct scatterlist
*sg
;
484 /* If sgpages == 0 then buf is used, else sg is used */
485 unsigned int sgpages
;
488 static void reclaim_sg_pages(struct scatterlist
*sg
, unsigned int nrpages
)
493 for (i
= 0; i
< nrpages
; i
++) {
494 page
= sg_page(&sg
[i
]);
502 /* Callers must take the port->outvq_lock */
503 static void reclaim_consumed_buffers(struct port
*port
)
505 struct buffer_token
*tok
;
508 if (!port
->portdev
) {
509 /* Device has been unplugged. vqs are already gone. */
512 while ((tok
= virtqueue_get_buf(port
->out_vq
, &len
))) {
514 reclaim_sg_pages(tok
->u
.sg
, tok
->sgpages
);
518 port
->outvq_full
= false;
522 static ssize_t
__send_to_port(struct port
*port
, struct scatterlist
*sg
,
523 int nents
, size_t in_count
,
524 struct buffer_token
*tok
, bool nonblock
)
526 struct virtqueue
*out_vq
;
531 out_vq
= port
->out_vq
;
533 spin_lock_irqsave(&port
->outvq_lock
, flags
);
535 reclaim_consumed_buffers(port
);
537 ret
= virtqueue_add_buf(out_vq
, sg
, nents
, 0, tok
, GFP_ATOMIC
);
539 /* Tell Host to go! */
540 virtqueue_kick(out_vq
);
548 port
->outvq_full
= true;
554 * Wait till the host acknowledges it pushed out the data we
555 * sent. This is done for data from the hvc_console; the tty
556 * operations are performed with spinlocks held so we can't
557 * sleep here. An alternative would be to copy the data to a
558 * buffer and relax the spinning requirement. The downside is
559 * we need to kmalloc a GFP_ATOMIC buffer each time the
560 * console driver writes something out.
562 while (!virtqueue_get_buf(out_vq
, &len
))
565 spin_unlock_irqrestore(&port
->outvq_lock
, flags
);
567 port
->stats
.bytes_sent
+= in_count
;
569 * We're expected to return the amount of data we wrote -- all
575 static ssize_t
send_buf(struct port
*port
, void *in_buf
, size_t in_count
,
578 struct scatterlist sg
[1];
579 struct buffer_token
*tok
;
581 tok
= kmalloc(sizeof(*tok
), GFP_ATOMIC
);
587 sg_init_one(sg
, in_buf
, in_count
);
589 return __send_to_port(port
, sg
, 1, in_count
, tok
, nonblock
);
592 static ssize_t
send_pages(struct port
*port
, struct scatterlist
*sg
, int nents
,
593 size_t in_count
, bool nonblock
)
595 struct buffer_token
*tok
;
597 tok
= kmalloc(sizeof(*tok
), GFP_ATOMIC
);
600 tok
->sgpages
= nents
;
603 return __send_to_port(port
, sg
, nents
, in_count
, tok
, nonblock
);
607 * Give out the data that's requested from the buffer that we have
610 static ssize_t
fill_readbuf(struct port
*port
, char *out_buf
, size_t out_count
,
613 struct port_buffer
*buf
;
616 if (!out_count
|| !port_has_data(port
))
620 out_count
= min(out_count
, buf
->len
- buf
->offset
);
625 ret
= copy_to_user(out_buf
, buf
->buf
+ buf
->offset
, out_count
);
629 memcpy(out_buf
, buf
->buf
+ buf
->offset
, out_count
);
632 buf
->offset
+= out_count
;
634 if (buf
->offset
== buf
->len
) {
636 * We're done using all the data in this buffer.
637 * Re-queue so that the Host can send us more data.
639 spin_lock_irqsave(&port
->inbuf_lock
, flags
);
642 if (add_inbuf(port
->in_vq
, buf
) < 0)
643 dev_warn(port
->dev
, "failed add_buf\n");
645 spin_unlock_irqrestore(&port
->inbuf_lock
, flags
);
647 /* Return the number of bytes actually copied */
651 /* The condition that must be true for polling to end */
652 static bool will_read_block(struct port
*port
)
654 if (!port
->guest_connected
) {
655 /* Port got hot-unplugged. Let's exit. */
658 return !port_has_data(port
) && port
->host_connected
;
661 static bool will_write_block(struct port
*port
)
665 if (!port
->guest_connected
) {
666 /* Port got hot-unplugged. Let's exit. */
669 if (!port
->host_connected
)
672 spin_lock_irq(&port
->outvq_lock
);
674 * Check if the Host has consumed any buffers since we last
675 * sent data (this is only applicable for nonblocking ports).
677 reclaim_consumed_buffers(port
);
678 ret
= port
->outvq_full
;
679 spin_unlock_irq(&port
->outvq_lock
);
684 static ssize_t
port_fops_read(struct file
*filp
, char __user
*ubuf
,
685 size_t count
, loff_t
*offp
)
690 port
= filp
->private_data
;
692 if (!port_has_data(port
)) {
694 * If nothing's connected on the host just return 0 in
695 * case of list_empty; this tells the userspace app
696 * that there's no connection
698 if (!port
->host_connected
)
700 if (filp
->f_flags
& O_NONBLOCK
)
703 ret
= wait_event_freezable(port
->waitqueue
,
704 !will_read_block(port
));
708 /* Port got hot-unplugged. */
709 if (!port
->guest_connected
)
712 * We could've received a disconnection message while we were
713 * waiting for more data.
715 * This check is not clubbed in the if() statement above as we
716 * might receive some data as well as the host could get
717 * disconnected after we got woken up from our wait. So we
718 * really want to give off whatever data we have and only then
719 * check for host_connected.
721 if (!port_has_data(port
) && !port
->host_connected
)
724 return fill_readbuf(port
, ubuf
, count
, true);
727 static int wait_port_writable(struct port
*port
, bool nonblock
)
731 if (will_write_block(port
)) {
735 ret
= wait_event_freezable(port
->waitqueue
,
736 !will_write_block(port
));
740 /* Port got hot-unplugged. */
741 if (!port
->guest_connected
)
747 static ssize_t
port_fops_write(struct file
*filp
, const char __user
*ubuf
,
748 size_t count
, loff_t
*offp
)
755 /* Userspace could be out to fool us */
759 port
= filp
->private_data
;
761 nonblock
= filp
->f_flags
& O_NONBLOCK
;
763 ret
= wait_port_writable(port
, nonblock
);
767 count
= min((size_t)(32 * 1024), count
);
769 buf
= kmalloc(count
, GFP_KERNEL
);
773 ret
= copy_from_user(buf
, ubuf
, count
);
780 * We now ask send_buf() to not spin for generic ports -- we
781 * can re-use the same code path that non-blocking file
782 * descriptors take for blocking file descriptors since the
783 * wait is already done and we're certain the write will go
784 * through to the host.
787 ret
= send_buf(port
, buf
, count
, nonblock
);
789 if (nonblock
&& ret
> 0)
802 struct scatterlist
*sg
;
805 static int pipe_to_sg(struct pipe_inode_info
*pipe
, struct pipe_buffer
*buf
,
806 struct splice_desc
*sd
)
808 struct sg_list
*sgl
= sd
->u
.data
;
809 unsigned int offset
, len
;
811 if (sgl
->n
== sgl
->size
)
814 /* Try lock this page */
815 if (buf
->ops
->steal(pipe
, buf
) == 0) {
816 /* Get reference and unlock page for moving */
818 unlock_page(buf
->page
);
820 len
= min(buf
->len
, sd
->len
);
821 sg_set_page(&(sgl
->sg
[sgl
->n
]), buf
->page
, len
, buf
->offset
);
823 /* Failback to copying a page */
824 struct page
*page
= alloc_page(GFP_KERNEL
);
825 char *src
= buf
->ops
->map(pipe
, buf
, 1);
832 offset
= sd
->pos
& ~PAGE_MASK
;
835 if (len
+ offset
> PAGE_SIZE
)
836 len
= PAGE_SIZE
- offset
;
838 memcpy(dst
+ offset
, src
+ buf
->offset
, len
);
841 buf
->ops
->unmap(pipe
, buf
, src
);
843 sg_set_page(&(sgl
->sg
[sgl
->n
]), page
, len
, offset
);
851 /* Faster zero-copy write by splicing */
852 static ssize_t
port_fops_splice_write(struct pipe_inode_info
*pipe
,
853 struct file
*filp
, loff_t
*ppos
,
854 size_t len
, unsigned int flags
)
856 struct port
*port
= filp
->private_data
;
859 struct splice_desc sd
= {
866 ret
= wait_port_writable(port
, filp
->f_flags
& O_NONBLOCK
);
872 sgl
.size
= pipe
->nrbufs
;
873 sgl
.sg
= kmalloc(sizeof(struct scatterlist
) * sgl
.size
, GFP_KERNEL
);
874 if (unlikely(!sgl
.sg
))
877 sg_init_table(sgl
.sg
, sgl
.size
);
878 ret
= __splice_from_pipe(pipe
, &sd
, pipe_to_sg
);
880 ret
= send_pages(port
, sgl
.sg
, sgl
.n
, sgl
.len
, true);
885 static unsigned int port_fops_poll(struct file
*filp
, poll_table
*wait
)
890 port
= filp
->private_data
;
891 poll_wait(filp
, &port
->waitqueue
, wait
);
893 if (!port
->guest_connected
) {
894 /* Port got unplugged */
898 if (!will_read_block(port
))
899 ret
|= POLLIN
| POLLRDNORM
;
900 if (!will_write_block(port
))
902 if (!port
->host_connected
)
908 static void remove_port(struct kref
*kref
);
910 static int port_fops_release(struct inode
*inode
, struct file
*filp
)
914 port
= filp
->private_data
;
916 /* Notify host of port being closed */
917 send_control_msg(port
, VIRTIO_CONSOLE_PORT_OPEN
, 0);
919 spin_lock_irq(&port
->inbuf_lock
);
920 port
->guest_connected
= false;
922 discard_port_data(port
);
924 spin_unlock_irq(&port
->inbuf_lock
);
926 spin_lock_irq(&port
->outvq_lock
);
927 reclaim_consumed_buffers(port
);
928 spin_unlock_irq(&port
->outvq_lock
);
931 * Locks aren't necessary here as a port can't be opened after
932 * unplug, and if a port isn't unplugged, a kref would already
933 * exist for the port. Plus, taking ports_lock here would
934 * create a dependency on other locks taken by functions
935 * inside remove_port if we're the last holder of the port,
936 * creating many problems.
938 kref_put(&port
->kref
, remove_port
);
943 static int port_fops_open(struct inode
*inode
, struct file
*filp
)
945 struct cdev
*cdev
= inode
->i_cdev
;
949 port
= find_port_by_devt(cdev
->dev
);
950 filp
->private_data
= port
;
952 /* Prevent against a port getting hot-unplugged at the same time */
953 spin_lock_irq(&port
->portdev
->ports_lock
);
954 kref_get(&port
->kref
);
955 spin_unlock_irq(&port
->portdev
->ports_lock
);
958 * Don't allow opening of console port devices -- that's done
961 if (is_console_port(port
)) {
966 /* Allow only one process to open a particular port at a time */
967 spin_lock_irq(&port
->inbuf_lock
);
968 if (port
->guest_connected
) {
969 spin_unlock_irq(&port
->inbuf_lock
);
974 port
->guest_connected
= true;
975 spin_unlock_irq(&port
->inbuf_lock
);
977 spin_lock_irq(&port
->outvq_lock
);
979 * There might be a chance that we missed reclaiming a few
980 * buffers in the window of the port getting previously closed
983 reclaim_consumed_buffers(port
);
984 spin_unlock_irq(&port
->outvq_lock
);
986 nonseekable_open(inode
, filp
);
988 /* Notify host of port being opened */
989 send_control_msg(filp
->private_data
, VIRTIO_CONSOLE_PORT_OPEN
, 1);
993 kref_put(&port
->kref
, remove_port
);
997 static int port_fops_fasync(int fd
, struct file
*filp
, int mode
)
1001 port
= filp
->private_data
;
1002 return fasync_helper(fd
, filp
, mode
, &port
->async_queue
);
1006 * The file operations that we support: programs in the guest can open
1007 * a console device, read from it, write to it, poll for data and
1008 * close it. The devices are at
1009 * /dev/vport<device number>p<port number>
1011 static const struct file_operations port_fops
= {
1012 .owner
= THIS_MODULE
,
1013 .open
= port_fops_open
,
1014 .read
= port_fops_read
,
1015 .write
= port_fops_write
,
1016 .splice_write
= port_fops_splice_write
,
1017 .poll
= port_fops_poll
,
1018 .release
= port_fops_release
,
1019 .fasync
= port_fops_fasync
,
1020 .llseek
= no_llseek
,
1024 * The put_chars() callback is pretty straightforward.
1026 * We turn the characters into a scatter-gather list, add it to the
1027 * output queue and then kick the Host. Then we sit here waiting for
1028 * it to finish: inefficient in theory, but in practice
1029 * implementations will do it immediately (lguest's Launcher does).
1031 static int put_chars(u32 vtermno
, const char *buf
, int count
)
1035 if (unlikely(early_put_chars
))
1036 return early_put_chars(vtermno
, buf
, count
);
1038 port
= find_port_by_vtermno(vtermno
);
1042 return send_buf(port
, (void *)buf
, count
, false);
1046 * get_chars() is the callback from the hvc_console infrastructure
1047 * when an interrupt is received.
1049 * We call out to fill_readbuf that gets us the required data from the
1050 * buffers that are queued up.
1052 static int get_chars(u32 vtermno
, char *buf
, int count
)
1056 /* If we've not set up the port yet, we have no input to give. */
1057 if (unlikely(early_put_chars
))
1060 port
= find_port_by_vtermno(vtermno
);
1064 /* If we don't have an input queue yet, we can't get input. */
1065 BUG_ON(!port
->in_vq
);
1067 return fill_readbuf(port
, buf
, count
, false);
1070 static void resize_console(struct port
*port
)
1072 struct virtio_device
*vdev
;
1074 /* The port could have been hot-unplugged */
1075 if (!port
|| !is_console_port(port
))
1078 vdev
= port
->portdev
->vdev
;
1079 if (virtio_has_feature(vdev
, VIRTIO_CONSOLE_F_SIZE
))
1080 hvc_resize(port
->cons
.hvc
, port
->cons
.ws
);
1083 /* We set the configuration at this point, since we now have a tty */
1084 static int notifier_add_vio(struct hvc_struct
*hp
, int data
)
1088 port
= find_port_by_vtermno(hp
->vtermno
);
1092 hp
->irq_requested
= 1;
1093 resize_console(port
);
1098 static void notifier_del_vio(struct hvc_struct
*hp
, int data
)
1100 hp
->irq_requested
= 0;
1103 /* The operations for console ports. */
1104 static const struct hv_ops hv_ops
= {
1105 .get_chars
= get_chars
,
1106 .put_chars
= put_chars
,
1107 .notifier_add
= notifier_add_vio
,
1108 .notifier_del
= notifier_del_vio
,
1109 .notifier_hangup
= notifier_del_vio
,
1113 * Console drivers are initialized very early so boot messages can go
1114 * out, so we do things slightly differently from the generic virtio
1115 * initialization of the net and block drivers.
1117 * At this stage, the console is output-only. It's too early to set
1118 * up a virtqueue, so we let the drivers do some boutique early-output
1121 int __init
virtio_cons_early_init(int (*put_chars
)(u32
, const char *, int))
1123 early_put_chars
= put_chars
;
1124 return hvc_instantiate(0, 0, &hv_ops
);
1127 int init_port_console(struct port
*port
)
1132 * The Host's telling us this port is a console port. Hook it
1133 * up with an hvc console.
1135 * To set up and manage our virtual console, we call
1138 * The first argument of hvc_alloc() is the virtual console
1139 * number. The second argument is the parameter for the
1140 * notification mechanism (like irq number). We currently
1141 * leave this as zero, virtqueues have implicit notifications.
1143 * The third argument is a "struct hv_ops" containing the
1144 * put_chars() get_chars(), notifier_add() and notifier_del()
1145 * pointers. The final argument is the output buffer size: we
1146 * can do any size, so we put PAGE_SIZE here.
1148 port
->cons
.vtermno
= pdrvdata
.next_vtermno
;
1150 port
->cons
.hvc
= hvc_alloc(port
->cons
.vtermno
, 0, &hv_ops
, PAGE_SIZE
);
1151 if (IS_ERR(port
->cons
.hvc
)) {
1152 ret
= PTR_ERR(port
->cons
.hvc
);
1154 "error %d allocating hvc for port\n", ret
);
1155 port
->cons
.hvc
= NULL
;
1158 spin_lock_irq(&pdrvdata_lock
);
1159 pdrvdata
.next_vtermno
++;
1160 list_add_tail(&port
->cons
.list
, &pdrvdata
.consoles
);
1161 spin_unlock_irq(&pdrvdata_lock
);
1162 port
->guest_connected
= true;
1165 * Start using the new console output if this is the first
1166 * console to come up.
1168 if (early_put_chars
)
1169 early_put_chars
= NULL
;
1171 /* Notify host of port being opened */
1172 send_control_msg(port
, VIRTIO_CONSOLE_PORT_OPEN
, 1);
1177 static ssize_t
show_port_name(struct device
*dev
,
1178 struct device_attribute
*attr
, char *buffer
)
1182 port
= dev_get_drvdata(dev
);
1184 return sprintf(buffer
, "%s\n", port
->name
);
1187 static DEVICE_ATTR(name
, S_IRUGO
, show_port_name
, NULL
);
1189 static struct attribute
*port_sysfs_entries
[] = {
1190 &dev_attr_name
.attr
,
1194 static struct attribute_group port_attribute_group
= {
1195 .name
= NULL
, /* put in device directory */
1196 .attrs
= port_sysfs_entries
,
1199 static ssize_t
debugfs_read(struct file
*filp
, char __user
*ubuf
,
1200 size_t count
, loff_t
*offp
)
1204 ssize_t ret
, out_offset
, out_count
;
1207 buf
= kmalloc(out_count
, GFP_KERNEL
);
1211 port
= filp
->private_data
;
1213 out_offset
+= snprintf(buf
+ out_offset
, out_count
,
1214 "name: %s\n", port
->name
? port
->name
: "");
1215 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1216 "guest_connected: %d\n", port
->guest_connected
);
1217 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1218 "host_connected: %d\n", port
->host_connected
);
1219 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1220 "outvq_full: %d\n", port
->outvq_full
);
1221 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1222 "bytes_sent: %lu\n", port
->stats
.bytes_sent
);
1223 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1224 "bytes_received: %lu\n",
1225 port
->stats
.bytes_received
);
1226 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1227 "bytes_discarded: %lu\n",
1228 port
->stats
.bytes_discarded
);
1229 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1231 is_console_port(port
) ? "yes" : "no");
1232 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1233 "console_vtermno: %u\n", port
->cons
.vtermno
);
1235 ret
= simple_read_from_buffer(ubuf
, count
, offp
, buf
, out_offset
);
1240 static const struct file_operations port_debugfs_ops
= {
1241 .owner
= THIS_MODULE
,
1242 .open
= simple_open
,
1243 .read
= debugfs_read
,
1246 static void set_console_size(struct port
*port
, u16 rows
, u16 cols
)
1248 if (!port
|| !is_console_port(port
))
1251 port
->cons
.ws
.ws_row
= rows
;
1252 port
->cons
.ws
.ws_col
= cols
;
1255 static unsigned int fill_queue(struct virtqueue
*vq
, spinlock_t
*lock
)
1257 struct port_buffer
*buf
;
1258 unsigned int nr_added_bufs
;
1263 buf
= alloc_buf(PAGE_SIZE
);
1267 spin_lock_irq(lock
);
1268 ret
= add_inbuf(vq
, buf
);
1270 spin_unlock_irq(lock
);
1275 spin_unlock_irq(lock
);
1278 return nr_added_bufs
;
1281 static void send_sigio_to_port(struct port
*port
)
1283 if (port
->async_queue
&& port
->guest_connected
)
1284 kill_fasync(&port
->async_queue
, SIGIO
, POLL_OUT
);
1287 static int add_port(struct ports_device
*portdev
, u32 id
)
1289 char debugfs_name
[16];
1291 struct port_buffer
*buf
;
1293 unsigned int nr_added_bufs
;
1296 port
= kmalloc(sizeof(*port
), GFP_KERNEL
);
1301 kref_init(&port
->kref
);
1303 port
->portdev
= portdev
;
1308 port
->cons
.hvc
= NULL
;
1309 port
->async_queue
= NULL
;
1311 port
->cons
.ws
.ws_row
= port
->cons
.ws
.ws_col
= 0;
1313 port
->host_connected
= port
->guest_connected
= false;
1314 port
->stats
= (struct port_stats
) { 0 };
1316 port
->outvq_full
= false;
1318 port
->in_vq
= portdev
->in_vqs
[port
->id
];
1319 port
->out_vq
= portdev
->out_vqs
[port
->id
];
1321 port
->cdev
= cdev_alloc();
1323 dev_err(&port
->portdev
->vdev
->dev
, "Error allocating cdev\n");
1327 port
->cdev
->ops
= &port_fops
;
1329 devt
= MKDEV(portdev
->chr_major
, id
);
1330 err
= cdev_add(port
->cdev
, devt
, 1);
1332 dev_err(&port
->portdev
->vdev
->dev
,
1333 "Error %d adding cdev for port %u\n", err
, id
);
1336 port
->dev
= device_create(pdrvdata
.class, &port
->portdev
->vdev
->dev
,
1337 devt
, port
, "vport%up%u",
1338 port
->portdev
->drv_index
, id
);
1339 if (IS_ERR(port
->dev
)) {
1340 err
= PTR_ERR(port
->dev
);
1341 dev_err(&port
->portdev
->vdev
->dev
,
1342 "Error %d creating device for port %u\n",
1347 spin_lock_init(&port
->inbuf_lock
);
1348 spin_lock_init(&port
->outvq_lock
);
1349 init_waitqueue_head(&port
->waitqueue
);
1351 /* Fill the in_vq with buffers so the host can send us data. */
1352 nr_added_bufs
= fill_queue(port
->in_vq
, &port
->inbuf_lock
);
1353 if (!nr_added_bufs
) {
1354 dev_err(port
->dev
, "Error allocating inbufs\n");
1360 * If we're not using multiport support, this has to be a console port
1362 if (!use_multiport(port
->portdev
)) {
1363 err
= init_port_console(port
);
1368 spin_lock_irq(&portdev
->ports_lock
);
1369 list_add_tail(&port
->list
, &port
->portdev
->ports
);
1370 spin_unlock_irq(&portdev
->ports_lock
);
1373 * Tell the Host we're set so that it can send us various
1374 * configuration parameters for this port (eg, port name,
1375 * caching, whether this is a console port, etc.)
1377 send_control_msg(port
, VIRTIO_CONSOLE_PORT_READY
, 1);
1379 if (pdrvdata
.debugfs_dir
) {
1381 * Finally, create the debugfs file that we can use to
1382 * inspect a port's state at any time
1384 sprintf(debugfs_name
, "vport%up%u",
1385 port
->portdev
->drv_index
, id
);
1386 port
->debugfs_file
= debugfs_create_file(debugfs_name
, 0444,
1387 pdrvdata
.debugfs_dir
,
1394 while ((buf
= virtqueue_detach_unused_buf(port
->in_vq
)))
1397 device_destroy(pdrvdata
.class, port
->dev
->devt
);
1399 cdev_del(port
->cdev
);
1403 /* The host might want to notify management sw about port add failure */
1404 __send_control_msg(portdev
, id
, VIRTIO_CONSOLE_PORT_READY
, 0);
1408 /* No users remain, remove all port-specific data. */
1409 static void remove_port(struct kref
*kref
)
1413 port
= container_of(kref
, struct port
, kref
);
1415 sysfs_remove_group(&port
->dev
->kobj
, &port_attribute_group
);
1416 device_destroy(pdrvdata
.class, port
->dev
->devt
);
1417 cdev_del(port
->cdev
);
1421 debugfs_remove(port
->debugfs_file
);
1426 static void remove_port_data(struct port
*port
)
1428 struct port_buffer
*buf
;
1430 /* Remove unused data this port might have received. */
1431 discard_port_data(port
);
1433 reclaim_consumed_buffers(port
);
1435 /* Remove buffers we queued up for the Host to send us data in. */
1436 while ((buf
= virtqueue_detach_unused_buf(port
->in_vq
)))
1441 * Port got unplugged. Remove port from portdev's list and drop the
1442 * kref reference. If no userspace has this port opened, it will
1443 * result in immediate removal the port.
1445 static void unplug_port(struct port
*port
)
1447 spin_lock_irq(&port
->portdev
->ports_lock
);
1448 list_del(&port
->list
);
1449 spin_unlock_irq(&port
->portdev
->ports_lock
);
1451 if (port
->guest_connected
) {
1452 port
->guest_connected
= false;
1453 port
->host_connected
= false;
1454 wake_up_interruptible(&port
->waitqueue
);
1456 /* Let the app know the port is going down. */
1457 send_sigio_to_port(port
);
1460 if (is_console_port(port
)) {
1461 spin_lock_irq(&pdrvdata_lock
);
1462 list_del(&port
->cons
.list
);
1463 spin_unlock_irq(&pdrvdata_lock
);
1464 hvc_remove(port
->cons
.hvc
);
1467 remove_port_data(port
);
1470 * We should just assume the device itself has gone off --
1471 * else a close on an open port later will try to send out a
1474 port
->portdev
= NULL
;
1477 * Locks around here are not necessary - a port can't be
1478 * opened after we removed the port struct from ports_list
1481 kref_put(&port
->kref
, remove_port
);
1484 /* Any private messages that the Host and Guest want to share */
1485 static void handle_control_message(struct ports_device
*portdev
,
1486 struct port_buffer
*buf
)
1488 struct virtio_console_control
*cpkt
;
1493 cpkt
= (struct virtio_console_control
*)(buf
->buf
+ buf
->offset
);
1495 port
= find_port_by_id(portdev
, cpkt
->id
);
1496 if (!port
&& cpkt
->event
!= VIRTIO_CONSOLE_PORT_ADD
) {
1497 /* No valid header at start of buffer. Drop it. */
1498 dev_dbg(&portdev
->vdev
->dev
,
1499 "Invalid index %u in control packet\n", cpkt
->id
);
1503 switch (cpkt
->event
) {
1504 case VIRTIO_CONSOLE_PORT_ADD
:
1506 dev_dbg(&portdev
->vdev
->dev
,
1507 "Port %u already added\n", port
->id
);
1508 send_control_msg(port
, VIRTIO_CONSOLE_PORT_READY
, 1);
1511 if (cpkt
->id
>= portdev
->config
.max_nr_ports
) {
1512 dev_warn(&portdev
->vdev
->dev
,
1513 "Request for adding port with out-of-bound id %u, max. supported id: %u\n",
1514 cpkt
->id
, portdev
->config
.max_nr_ports
- 1);
1517 add_port(portdev
, cpkt
->id
);
1519 case VIRTIO_CONSOLE_PORT_REMOVE
:
1522 case VIRTIO_CONSOLE_CONSOLE_PORT
:
1525 if (is_console_port(port
))
1528 init_port_console(port
);
1529 complete(&early_console_added
);
1531 * Could remove the port here in case init fails - but
1532 * have to notify the host first.
1535 case VIRTIO_CONSOLE_RESIZE
: {
1541 if (!is_console_port(port
))
1544 memcpy(&size
, buf
->buf
+ buf
->offset
+ sizeof(*cpkt
),
1546 set_console_size(port
, size
.rows
, size
.cols
);
1548 port
->cons
.hvc
->irq_requested
= 1;
1549 resize_console(port
);
1552 case VIRTIO_CONSOLE_PORT_OPEN
:
1553 port
->host_connected
= cpkt
->value
;
1554 wake_up_interruptible(&port
->waitqueue
);
1556 * If the host port got closed and the host had any
1557 * unconsumed buffers, we'll be able to reclaim them
1560 spin_lock_irq(&port
->outvq_lock
);
1561 reclaim_consumed_buffers(port
);
1562 spin_unlock_irq(&port
->outvq_lock
);
1565 * If the guest is connected, it'll be interested in
1566 * knowing the host connection state changed.
1568 send_sigio_to_port(port
);
1570 case VIRTIO_CONSOLE_PORT_NAME
:
1572 * If we woke up after hibernation, we can get this
1573 * again. Skip it in that case.
1579 * Skip the size of the header and the cpkt to get the size
1580 * of the name that was sent
1582 name_size
= buf
->len
- buf
->offset
- sizeof(*cpkt
) + 1;
1584 port
->name
= kmalloc(name_size
, GFP_KERNEL
);
1587 "Not enough space to store port name\n");
1590 strncpy(port
->name
, buf
->buf
+ buf
->offset
+ sizeof(*cpkt
),
1592 port
->name
[name_size
- 1] = 0;
1595 * Since we only have one sysfs attribute, 'name',
1596 * create it only if we have a name for the port.
1598 err
= sysfs_create_group(&port
->dev
->kobj
,
1599 &port_attribute_group
);
1602 "Error %d creating sysfs device attributes\n",
1606 * Generate a udev event so that appropriate
1607 * symlinks can be created based on udev
1610 kobject_uevent(&port
->dev
->kobj
, KOBJ_CHANGE
);
1616 static void control_work_handler(struct work_struct
*work
)
1618 struct ports_device
*portdev
;
1619 struct virtqueue
*vq
;
1620 struct port_buffer
*buf
;
1623 portdev
= container_of(work
, struct ports_device
, control_work
);
1624 vq
= portdev
->c_ivq
;
1626 spin_lock(&portdev
->cvq_lock
);
1627 while ((buf
= virtqueue_get_buf(vq
, &len
))) {
1628 spin_unlock(&portdev
->cvq_lock
);
1633 handle_control_message(portdev
, buf
);
1635 spin_lock(&portdev
->cvq_lock
);
1636 if (add_inbuf(portdev
->c_ivq
, buf
) < 0) {
1637 dev_warn(&portdev
->vdev
->dev
,
1638 "Error adding buffer to queue\n");
1642 spin_unlock(&portdev
->cvq_lock
);
1645 static void out_intr(struct virtqueue
*vq
)
1649 port
= find_port_by_vq(vq
->vdev
->priv
, vq
);
1653 wake_up_interruptible(&port
->waitqueue
);
1656 static void in_intr(struct virtqueue
*vq
)
1659 unsigned long flags
;
1661 port
= find_port_by_vq(vq
->vdev
->priv
, vq
);
1665 spin_lock_irqsave(&port
->inbuf_lock
, flags
);
1666 port
->inbuf
= get_inbuf(port
);
1669 * Don't queue up data when port is closed. This condition
1670 * can be reached when a console port is not yet connected (no
1671 * tty is spawned) and the host sends out data to console
1672 * ports. For generic serial ports, the host won't
1673 * (shouldn't) send data till the guest is connected.
1675 if (!port
->guest_connected
)
1676 discard_port_data(port
);
1678 spin_unlock_irqrestore(&port
->inbuf_lock
, flags
);
1680 wake_up_interruptible(&port
->waitqueue
);
1682 /* Send a SIGIO indicating new data in case the process asked for it */
1683 send_sigio_to_port(port
);
1685 if (is_console_port(port
) && hvc_poll(port
->cons
.hvc
))
1689 static void control_intr(struct virtqueue
*vq
)
1691 struct ports_device
*portdev
;
1693 portdev
= vq
->vdev
->priv
;
1694 schedule_work(&portdev
->control_work
);
1697 static void config_intr(struct virtio_device
*vdev
)
1699 struct ports_device
*portdev
;
1701 portdev
= vdev
->priv
;
1703 if (!use_multiport(portdev
)) {
1707 vdev
->config
->get(vdev
,
1708 offsetof(struct virtio_console_config
, cols
),
1709 &cols
, sizeof(u16
));
1710 vdev
->config
->get(vdev
,
1711 offsetof(struct virtio_console_config
, rows
),
1712 &rows
, sizeof(u16
));
1714 port
= find_port_by_id(portdev
, 0);
1715 set_console_size(port
, rows
, cols
);
1718 * We'll use this way of resizing only for legacy
1719 * support. For newer userspace
1720 * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
1721 * to indicate console size changes so that it can be
1724 resize_console(port
);
1728 static int init_vqs(struct ports_device
*portdev
)
1730 vq_callback_t
**io_callbacks
;
1732 struct virtqueue
**vqs
;
1733 u32 i
, j
, nr_ports
, nr_queues
;
1736 nr_ports
= portdev
->config
.max_nr_ports
;
1737 nr_queues
= use_multiport(portdev
) ? (nr_ports
+ 1) * 2 : 2;
1739 vqs
= kmalloc(nr_queues
* sizeof(struct virtqueue
*), GFP_KERNEL
);
1740 io_callbacks
= kmalloc(nr_queues
* sizeof(vq_callback_t
*), GFP_KERNEL
);
1741 io_names
= kmalloc(nr_queues
* sizeof(char *), GFP_KERNEL
);
1742 portdev
->in_vqs
= kmalloc(nr_ports
* sizeof(struct virtqueue
*),
1744 portdev
->out_vqs
= kmalloc(nr_ports
* sizeof(struct virtqueue
*),
1746 if (!vqs
|| !io_callbacks
|| !io_names
|| !portdev
->in_vqs
||
1747 !portdev
->out_vqs
) {
1753 * For backward compat (newer host but older guest), the host
1754 * spawns a console port first and also inits the vqs for port
1758 io_callbacks
[j
] = in_intr
;
1759 io_callbacks
[j
+ 1] = out_intr
;
1760 io_names
[j
] = "input";
1761 io_names
[j
+ 1] = "output";
1764 if (use_multiport(portdev
)) {
1765 io_callbacks
[j
] = control_intr
;
1766 io_callbacks
[j
+ 1] = NULL
;
1767 io_names
[j
] = "control-i";
1768 io_names
[j
+ 1] = "control-o";
1770 for (i
= 1; i
< nr_ports
; i
++) {
1772 io_callbacks
[j
] = in_intr
;
1773 io_callbacks
[j
+ 1] = out_intr
;
1774 io_names
[j
] = "input";
1775 io_names
[j
+ 1] = "output";
1778 /* Find the queues. */
1779 err
= portdev
->vdev
->config
->find_vqs(portdev
->vdev
, nr_queues
, vqs
,
1781 (const char **)io_names
);
1786 portdev
->in_vqs
[0] = vqs
[0];
1787 portdev
->out_vqs
[0] = vqs
[1];
1789 if (use_multiport(portdev
)) {
1790 portdev
->c_ivq
= vqs
[j
];
1791 portdev
->c_ovq
= vqs
[j
+ 1];
1793 for (i
= 1; i
< nr_ports
; i
++) {
1795 portdev
->in_vqs
[i
] = vqs
[j
];
1796 portdev
->out_vqs
[i
] = vqs
[j
+ 1];
1800 kfree(io_callbacks
);
1806 kfree(portdev
->out_vqs
);
1807 kfree(portdev
->in_vqs
);
1809 kfree(io_callbacks
);
1815 static const struct file_operations portdev_fops
= {
1816 .owner
= THIS_MODULE
,
1819 static void remove_vqs(struct ports_device
*portdev
)
1821 portdev
->vdev
->config
->del_vqs(portdev
->vdev
);
1822 kfree(portdev
->in_vqs
);
1823 kfree(portdev
->out_vqs
);
1826 static void remove_controlq_data(struct ports_device
*portdev
)
1828 struct port_buffer
*buf
;
1831 if (!use_multiport(portdev
))
1834 while ((buf
= virtqueue_get_buf(portdev
->c_ivq
, &len
)))
1837 while ((buf
= virtqueue_detach_unused_buf(portdev
->c_ivq
)))
1842 * Once we're further in boot, we get probed like any other virtio
1845 * If the host also supports multiple console ports, we check the
1846 * config space to see how many ports the host has spawned. We
1847 * initialize each port found.
1849 static int __devinit
virtcons_probe(struct virtio_device
*vdev
)
1851 struct ports_device
*portdev
;
1854 bool early
= early_put_chars
!= NULL
;
1856 /* Ensure to read early_put_chars now */
1859 portdev
= kmalloc(sizeof(*portdev
), GFP_KERNEL
);
1865 /* Attach this portdev to this virtio_device, and vice-versa. */
1866 portdev
->vdev
= vdev
;
1867 vdev
->priv
= portdev
;
1869 spin_lock_irq(&pdrvdata_lock
);
1870 portdev
->drv_index
= pdrvdata
.index
++;
1871 spin_unlock_irq(&pdrvdata_lock
);
1873 portdev
->chr_major
= register_chrdev(0, "virtio-portsdev",
1875 if (portdev
->chr_major
< 0) {
1877 "Error %d registering chrdev for device %u\n",
1878 portdev
->chr_major
, portdev
->drv_index
);
1879 err
= portdev
->chr_major
;
1884 portdev
->config
.max_nr_ports
= 1;
1885 if (virtio_config_val(vdev
, VIRTIO_CONSOLE_F_MULTIPORT
,
1886 offsetof(struct virtio_console_config
,
1888 &portdev
->config
.max_nr_ports
) == 0)
1891 err
= init_vqs(portdev
);
1893 dev_err(&vdev
->dev
, "Error %d initializing vqs\n", err
);
1897 spin_lock_init(&portdev
->ports_lock
);
1898 INIT_LIST_HEAD(&portdev
->ports
);
1901 unsigned int nr_added_bufs
;
1903 spin_lock_init(&portdev
->cvq_lock
);
1904 INIT_WORK(&portdev
->control_work
, &control_work_handler
);
1906 nr_added_bufs
= fill_queue(portdev
->c_ivq
, &portdev
->cvq_lock
);
1907 if (!nr_added_bufs
) {
1909 "Error allocating buffers for control queue\n");
1915 * For backward compatibility: Create a console port
1916 * if we're running on older host.
1918 add_port(portdev
, 0);
1921 spin_lock_irq(&pdrvdata_lock
);
1922 list_add_tail(&portdev
->list
, &pdrvdata
.portdevs
);
1923 spin_unlock_irq(&pdrvdata_lock
);
1925 __send_control_msg(portdev
, VIRTIO_CONSOLE_BAD_ID
,
1926 VIRTIO_CONSOLE_DEVICE_READY
, 1);
1929 * If there was an early virtio console, assume that there are no
1930 * other consoles. We need to wait until the hvc_alloc matches the
1931 * hvc_instantiate, otherwise tty_open will complain, resulting in
1932 * a "Warning: unable to open an initial console" boot failure.
1933 * Without multiport this is done in add_port above. With multiport
1934 * this might take some host<->guest communication - thus we have to
1937 if (multiport
&& early
)
1938 wait_for_completion(&early_console_added
);
1943 /* The host might want to notify mgmt sw about device add failure */
1944 __send_control_msg(portdev
, VIRTIO_CONSOLE_BAD_ID
,
1945 VIRTIO_CONSOLE_DEVICE_READY
, 0);
1946 remove_vqs(portdev
);
1948 unregister_chrdev(portdev
->chr_major
, "virtio-portsdev");
1955 static void virtcons_remove(struct virtio_device
*vdev
)
1957 struct ports_device
*portdev
;
1958 struct port
*port
, *port2
;
1960 portdev
= vdev
->priv
;
1962 spin_lock_irq(&pdrvdata_lock
);
1963 list_del(&portdev
->list
);
1964 spin_unlock_irq(&pdrvdata_lock
);
1966 /* Disable interrupts for vqs */
1967 vdev
->config
->reset(vdev
);
1968 /* Finish up work that's lined up */
1969 cancel_work_sync(&portdev
->control_work
);
1971 list_for_each_entry_safe(port
, port2
, &portdev
->ports
, list
)
1974 unregister_chrdev(portdev
->chr_major
, "virtio-portsdev");
1977 * When yanking out a device, we immediately lose the
1978 * (device-side) queues. So there's no point in keeping the
1979 * guest side around till we drop our final reference. This
1980 * also means that any ports which are in an open state will
1981 * have to just stop using the port, as the vqs are going
1984 remove_controlq_data(portdev
);
1985 remove_vqs(portdev
);
1989 static struct virtio_device_id id_table
[] = {
1990 { VIRTIO_ID_CONSOLE
, VIRTIO_DEV_ANY_ID
},
1994 static unsigned int features
[] = {
1995 VIRTIO_CONSOLE_F_SIZE
,
1996 VIRTIO_CONSOLE_F_MULTIPORT
,
2000 static int virtcons_freeze(struct virtio_device
*vdev
)
2002 struct ports_device
*portdev
;
2005 portdev
= vdev
->priv
;
2007 vdev
->config
->reset(vdev
);
2009 virtqueue_disable_cb(portdev
->c_ivq
);
2010 cancel_work_sync(&portdev
->control_work
);
2012 * Once more: if control_work_handler() was running, it would
2013 * enable the cb as the last step.
2015 virtqueue_disable_cb(portdev
->c_ivq
);
2016 remove_controlq_data(portdev
);
2018 list_for_each_entry(port
, &portdev
->ports
, list
) {
2019 virtqueue_disable_cb(port
->in_vq
);
2020 virtqueue_disable_cb(port
->out_vq
);
2022 * We'll ask the host later if the new invocation has
2023 * the port opened or closed.
2025 port
->host_connected
= false;
2026 remove_port_data(port
);
2028 remove_vqs(portdev
);
2033 static int virtcons_restore(struct virtio_device
*vdev
)
2035 struct ports_device
*portdev
;
2039 portdev
= vdev
->priv
;
2041 ret
= init_vqs(portdev
);
2045 if (use_multiport(portdev
))
2046 fill_queue(portdev
->c_ivq
, &portdev
->cvq_lock
);
2048 list_for_each_entry(port
, &portdev
->ports
, list
) {
2049 port
->in_vq
= portdev
->in_vqs
[port
->id
];
2050 port
->out_vq
= portdev
->out_vqs
[port
->id
];
2052 fill_queue(port
->in_vq
, &port
->inbuf_lock
);
2054 /* Get port open/close status on the host */
2055 send_control_msg(port
, VIRTIO_CONSOLE_PORT_READY
, 1);
2058 * If a port was open at the time of suspending, we
2059 * have to let the host know that it's still open.
2061 if (port
->guest_connected
)
2062 send_control_msg(port
, VIRTIO_CONSOLE_PORT_OPEN
, 1);
2068 static struct virtio_driver virtio_console
= {
2069 .feature_table
= features
,
2070 .feature_table_size
= ARRAY_SIZE(features
),
2071 .driver
.name
= KBUILD_MODNAME
,
2072 .driver
.owner
= THIS_MODULE
,
2073 .id_table
= id_table
,
2074 .probe
= virtcons_probe
,
2075 .remove
= virtcons_remove
,
2076 .config_changed
= config_intr
,
2078 .freeze
= virtcons_freeze
,
2079 .restore
= virtcons_restore
,
2083 static int __init
init(void)
2087 pdrvdata
.class = class_create(THIS_MODULE
, "virtio-ports");
2088 if (IS_ERR(pdrvdata
.class)) {
2089 err
= PTR_ERR(pdrvdata
.class);
2090 pr_err("Error %d creating virtio-ports class\n", err
);
2094 pdrvdata
.debugfs_dir
= debugfs_create_dir("virtio-ports", NULL
);
2095 if (!pdrvdata
.debugfs_dir
) {
2096 pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
2097 PTR_ERR(pdrvdata
.debugfs_dir
));
2099 INIT_LIST_HEAD(&pdrvdata
.consoles
);
2100 INIT_LIST_HEAD(&pdrvdata
.portdevs
);
2102 err
= register_virtio_driver(&virtio_console
);
2104 pr_err("Error %d registering virtio driver\n", err
);
2109 if (pdrvdata
.debugfs_dir
)
2110 debugfs_remove_recursive(pdrvdata
.debugfs_dir
);
2111 class_destroy(pdrvdata
.class);
2115 static void __exit
fini(void)
2117 unregister_virtio_driver(&virtio_console
);
2119 class_destroy(pdrvdata
.class);
2120 if (pdrvdata
.debugfs_dir
)
2121 debugfs_remove_recursive(pdrvdata
.debugfs_dir
);
2126 MODULE_DEVICE_TABLE(virtio
, id_table
);
2127 MODULE_DESCRIPTION("Virtio console driver");
2128 MODULE_LICENSE("GPL");