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 <linux/dma-mapping.h>
41 #include <linux/kconfig.h>
42 #include "../tty/hvc/hvc_console.h"
44 #define is_rproc_enabled IS_ENABLED(CONFIG_REMOTEPROC)
47 * This is a global struct for storing common data for all the devices
48 * this driver handles.
50 * Mainly, it has a linked list for all the consoles in one place so
51 * that callbacks from hvc for get_chars(), put_chars() work properly
52 * across multiple devices and multiple ports per device.
54 struct ports_driver_data
{
55 /* Used for registering chardevs */
58 /* Used for exporting per-port information to debugfs */
59 struct dentry
*debugfs_dir
;
61 /* List of all the devices we're handling */
62 struct list_head portdevs
;
65 * This is used to keep track of the number of hvc consoles
66 * spawned by this driver. This number is given as the first
67 * argument to hvc_alloc(). To correctly map an initial
68 * console spawned via hvc_instantiate to the console being
69 * hooked up via hvc_alloc, we need to pass the same vtermno.
71 * We also just assume the first console being initialised was
72 * the first one that got used as the initial console.
74 unsigned int next_vtermno
;
76 /* All the console devices handled by this driver */
77 struct list_head consoles
;
79 static struct ports_driver_data pdrvdata
;
81 static DEFINE_SPINLOCK(pdrvdata_lock
);
82 static DECLARE_COMPLETION(early_console_added
);
84 /* This struct holds information that's relevant only for console ports */
86 /* We'll place all consoles in a list in the pdrvdata struct */
87 struct list_head list
;
89 /* The hvc device associated with this console port */
90 struct hvc_struct
*hvc
;
92 /* The size of the console */
96 * This number identifies the number that we used to register
97 * with hvc in hvc_instantiate() and hvc_alloc(); this is the
98 * number passed on by the hvc callbacks to us to
99 * differentiate between the other console ports handled by
108 /* size of the buffer in *buf above */
111 /* used length of the buffer */
113 /* offset in the buf from which to consume data */
116 /* DMA address of buffer */
119 /* Device we got DMA memory from */
122 /* List of pending dma buffers to free */
123 struct list_head list
;
125 /* If sgpages == 0 then buf is used */
126 unsigned int sgpages
;
128 /* sg is used if spages > 0. sg must be the last in is struct */
129 struct scatterlist sg
[0];
133 * This is a per-device struct that stores data common to all the
134 * ports for that device (vdev->priv).
136 struct ports_device
{
137 /* Next portdev in the list, head is in the pdrvdata struct */
138 struct list_head list
;
141 * Workqueue handlers where we process deferred work after
144 struct work_struct control_work
;
146 struct list_head ports
;
148 /* To protect the list of ports */
149 spinlock_t ports_lock
;
151 /* To protect the vq operations for the control channel */
152 spinlock_t c_ivq_lock
;
153 spinlock_t c_ovq_lock
;
155 /* The current config space is stored here */
156 struct virtio_console_config config
;
158 /* The virtio device we're associated with */
159 struct virtio_device
*vdev
;
162 * A couple of virtqueues for the control channel: one for
163 * guest->host transfers, one for host->guest transfers
165 struct virtqueue
*c_ivq
, *c_ovq
;
167 /* Array of per-port IO virtqueues */
168 struct virtqueue
**in_vqs
, **out_vqs
;
170 /* Major number for this device. Ports will be created as minors. */
175 unsigned long bytes_sent
, bytes_received
, bytes_discarded
;
178 /* This struct holds the per-port data */
180 /* Next port in the list, head is in the ports_device */
181 struct list_head list
;
183 /* Pointer to the parent virtio_console device */
184 struct ports_device
*portdev
;
186 /* The current buffer from which data has to be fed to readers */
187 struct port_buffer
*inbuf
;
190 * To protect the operations on the in_vq associated with this
191 * port. Has to be a spinlock because it can be called from
192 * interrupt context (get_char()).
194 spinlock_t inbuf_lock
;
196 /* Protect the operations on the out_vq. */
197 spinlock_t outvq_lock
;
199 /* The IO vqs for this port */
200 struct virtqueue
*in_vq
, *out_vq
;
202 /* File in the debugfs directory that exposes this port's information */
203 struct dentry
*debugfs_file
;
206 * Keep count of the bytes sent, received and discarded for
207 * this port for accounting and debugging purposes. These
208 * counts are not reset across port open / close events.
210 struct port_stats stats
;
213 * The entries in this struct will be valid if this port is
214 * hooked up to an hvc console
218 /* Each port associates with a separate char device */
222 /* Reference-counting to handle port hot-unplugs and file operations */
225 /* A waitqueue for poll() or blocking read operations */
226 wait_queue_head_t waitqueue
;
228 /* The 'name' of the port that we expose via sysfs properties */
231 /* We can notify apps of host connect / disconnect events via SIGIO */
232 struct fasync_struct
*async_queue
;
234 /* The 'id' to identify the port with the Host */
239 /* Is the host device open */
242 /* We should allow only one process to open a port */
243 bool guest_connected
;
246 /* This is the very early arch-specified put chars function. */
247 static int (*early_put_chars
)(u32
, const char *, int);
249 static struct port
*find_port_by_vtermno(u32 vtermno
)
252 struct console
*cons
;
255 spin_lock_irqsave(&pdrvdata_lock
, flags
);
256 list_for_each_entry(cons
, &pdrvdata
.consoles
, list
) {
257 if (cons
->vtermno
== vtermno
) {
258 port
= container_of(cons
, struct port
, cons
);
264 spin_unlock_irqrestore(&pdrvdata_lock
, flags
);
268 static struct port
*find_port_by_devt_in_portdev(struct ports_device
*portdev
,
274 spin_lock_irqsave(&portdev
->ports_lock
, flags
);
275 list_for_each_entry(port
, &portdev
->ports
, list
)
276 if (port
->cdev
->dev
== dev
)
280 spin_unlock_irqrestore(&portdev
->ports_lock
, flags
);
285 static struct port
*find_port_by_devt(dev_t dev
)
287 struct ports_device
*portdev
;
291 spin_lock_irqsave(&pdrvdata_lock
, flags
);
292 list_for_each_entry(portdev
, &pdrvdata
.portdevs
, list
) {
293 port
= find_port_by_devt_in_portdev(portdev
, dev
);
299 spin_unlock_irqrestore(&pdrvdata_lock
, flags
);
303 static struct port
*find_port_by_id(struct ports_device
*portdev
, u32 id
)
308 spin_lock_irqsave(&portdev
->ports_lock
, flags
);
309 list_for_each_entry(port
, &portdev
->ports
, list
)
314 spin_unlock_irqrestore(&portdev
->ports_lock
, flags
);
319 static struct port
*find_port_by_vq(struct ports_device
*portdev
,
320 struct virtqueue
*vq
)
325 spin_lock_irqsave(&portdev
->ports_lock
, flags
);
326 list_for_each_entry(port
, &portdev
->ports
, list
)
327 if (port
->in_vq
== vq
|| port
->out_vq
== vq
)
331 spin_unlock_irqrestore(&portdev
->ports_lock
, flags
);
335 static bool is_console_port(struct port
*port
)
342 static bool is_rproc_serial(const struct virtio_device
*vdev
)
344 return is_rproc_enabled
&& vdev
->id
.device
== VIRTIO_ID_RPROC_SERIAL
;
347 static inline bool use_multiport(struct ports_device
*portdev
)
350 * This condition can be true when put_chars is called from
355 return portdev
->vdev
->features
[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT
);
358 static DEFINE_SPINLOCK(dma_bufs_lock
);
359 static LIST_HEAD(pending_free_dma_bufs
);
361 static void free_buf(struct port_buffer
*buf
, bool can_sleep
)
365 for (i
= 0; i
< buf
->sgpages
; i
++) {
366 struct page
*page
= sg_page(&buf
->sg
[i
]);
374 } else if (is_rproc_enabled
) {
377 /* dma_free_coherent requires interrupts to be enabled. */
379 /* queue up dma-buffers to be freed later */
380 spin_lock_irqsave(&dma_bufs_lock
, flags
);
381 list_add_tail(&buf
->list
, &pending_free_dma_bufs
);
382 spin_unlock_irqrestore(&dma_bufs_lock
, flags
);
385 dma_free_coherent(buf
->dev
, buf
->size
, buf
->buf
, buf
->dma
);
387 /* Release device refcnt and allow it to be freed */
388 put_device(buf
->dev
);
394 static void reclaim_dma_bufs(void)
397 struct port_buffer
*buf
, *tmp
;
400 if (list_empty(&pending_free_dma_bufs
))
403 /* Create a copy of the pending_free_dma_bufs while holding the lock */
404 spin_lock_irqsave(&dma_bufs_lock
, flags
);
405 list_cut_position(&tmp_list
, &pending_free_dma_bufs
,
406 pending_free_dma_bufs
.prev
);
407 spin_unlock_irqrestore(&dma_bufs_lock
, flags
);
409 /* Release the dma buffers, without irqs enabled */
410 list_for_each_entry_safe(buf
, tmp
, &tmp_list
, list
) {
411 list_del(&buf
->list
);
416 static struct port_buffer
*alloc_buf(struct virtqueue
*vq
, size_t buf_size
,
419 struct port_buffer
*buf
;
424 * Allocate buffer and the sg list. The sg list array is allocated
425 * directly after the port_buffer struct.
427 buf
= kmalloc(sizeof(*buf
) + sizeof(struct scatterlist
) * pages
,
432 buf
->sgpages
= pages
;
439 if (is_rproc_serial(vq
->vdev
)) {
441 * Allocate DMA memory from ancestor. When a virtio
442 * device is created by remoteproc, the DMA memory is
443 * associated with the grandparent device:
444 * vdev => rproc => platform-dev.
445 * The code here would have been less quirky if
446 * DMA_MEMORY_INCLUDES_CHILDREN had been supported
449 if (!vq
->vdev
->dev
.parent
|| !vq
->vdev
->dev
.parent
->parent
)
451 buf
->dev
= vq
->vdev
->dev
.parent
->parent
;
453 /* Increase device refcnt to avoid freeing it */
454 get_device(buf
->dev
);
455 buf
->buf
= dma_alloc_coherent(buf
->dev
, buf_size
, &buf
->dma
,
459 buf
->buf
= kmalloc(buf_size
, GFP_KERNEL
);
466 buf
->size
= buf_size
;
475 /* Callers should take appropriate locks */
476 static struct port_buffer
*get_inbuf(struct port
*port
)
478 struct port_buffer
*buf
;
484 buf
= virtqueue_get_buf(port
->in_vq
, &len
);
488 port
->stats
.bytes_received
+= len
;
494 * Create a scatter-gather list representing our input buffer and put
497 * Callers should take appropriate locks.
499 static int add_inbuf(struct virtqueue
*vq
, struct port_buffer
*buf
)
501 struct scatterlist sg
[1];
504 sg_init_one(sg
, buf
->buf
, buf
->size
);
506 ret
= virtqueue_add_inbuf(vq
, sg
, 1, buf
, GFP_ATOMIC
);
513 /* Discard any unread data this port has. Callers lockers. */
514 static void discard_port_data(struct port
*port
)
516 struct port_buffer
*buf
;
519 if (!port
->portdev
) {
520 /* Device has been unplugged. vqs are already gone. */
523 buf
= get_inbuf(port
);
527 port
->stats
.bytes_discarded
+= buf
->len
- buf
->offset
;
528 if (add_inbuf(port
->in_vq
, buf
) < 0) {
530 free_buf(buf
, false);
533 buf
= get_inbuf(port
);
536 dev_warn(port
->dev
, "Errors adding %d buffers back to vq\n",
540 static bool port_has_data(struct port
*port
)
546 spin_lock_irqsave(&port
->inbuf_lock
, flags
);
547 port
->inbuf
= get_inbuf(port
);
551 spin_unlock_irqrestore(&port
->inbuf_lock
, flags
);
555 static ssize_t
__send_control_msg(struct ports_device
*portdev
, u32 port_id
,
556 unsigned int event
, unsigned int value
)
558 struct scatterlist sg
[1];
559 struct virtio_console_control cpkt
;
560 struct virtqueue
*vq
;
563 if (!use_multiport(portdev
))
572 sg_init_one(sg
, &cpkt
, sizeof(cpkt
));
574 spin_lock(&portdev
->c_ovq_lock
);
575 if (virtqueue_add_outbuf(vq
, sg
, 1, &cpkt
, GFP_ATOMIC
) == 0) {
577 while (!virtqueue_get_buf(vq
, &len
))
580 spin_unlock(&portdev
->c_ovq_lock
);
584 static ssize_t
send_control_msg(struct port
*port
, unsigned int event
,
587 /* Did the port get unplugged before userspace closed it? */
589 return __send_control_msg(port
->portdev
, port
->id
, event
, value
);
594 /* Callers must take the port->outvq_lock */
595 static void reclaim_consumed_buffers(struct port
*port
)
597 struct port_buffer
*buf
;
600 if (!port
->portdev
) {
601 /* Device has been unplugged. vqs are already gone. */
604 while ((buf
= virtqueue_get_buf(port
->out_vq
, &len
))) {
605 free_buf(buf
, false);
606 port
->outvq_full
= false;
610 static ssize_t
__send_to_port(struct port
*port
, struct scatterlist
*sg
,
611 int nents
, size_t in_count
,
612 void *data
, bool nonblock
)
614 struct virtqueue
*out_vq
;
619 out_vq
= port
->out_vq
;
621 spin_lock_irqsave(&port
->outvq_lock
, flags
);
623 reclaim_consumed_buffers(port
);
625 err
= virtqueue_add_outbuf(out_vq
, sg
, nents
, data
, GFP_ATOMIC
);
627 /* Tell Host to go! */
628 virtqueue_kick(out_vq
);
635 if (out_vq
->num_free
== 0)
636 port
->outvq_full
= true;
642 * Wait till the host acknowledges it pushed out the data we
643 * sent. This is done for data from the hvc_console; the tty
644 * operations are performed with spinlocks held so we can't
645 * sleep here. An alternative would be to copy the data to a
646 * buffer and relax the spinning requirement. The downside is
647 * we need to kmalloc a GFP_ATOMIC buffer each time the
648 * console driver writes something out.
650 while (!virtqueue_get_buf(out_vq
, &len
))
653 spin_unlock_irqrestore(&port
->outvq_lock
, flags
);
655 port
->stats
.bytes_sent
+= in_count
;
657 * We're expected to return the amount of data we wrote -- all
664 * Give out the data that's requested from the buffer that we have
667 static ssize_t
fill_readbuf(struct port
*port
, char *out_buf
, size_t out_count
,
670 struct port_buffer
*buf
;
673 if (!out_count
|| !port_has_data(port
))
677 out_count
= min(out_count
, buf
->len
- buf
->offset
);
682 ret
= copy_to_user(out_buf
, buf
->buf
+ buf
->offset
, out_count
);
686 memcpy(out_buf
, buf
->buf
+ buf
->offset
, out_count
);
689 buf
->offset
+= out_count
;
691 if (buf
->offset
== buf
->len
) {
693 * We're done using all the data in this buffer.
694 * Re-queue so that the Host can send us more data.
696 spin_lock_irqsave(&port
->inbuf_lock
, flags
);
699 if (add_inbuf(port
->in_vq
, buf
) < 0)
700 dev_warn(port
->dev
, "failed add_buf\n");
702 spin_unlock_irqrestore(&port
->inbuf_lock
, flags
);
704 /* Return the number of bytes actually copied */
708 /* The condition that must be true for polling to end */
709 static bool will_read_block(struct port
*port
)
711 if (!port
->guest_connected
) {
712 /* Port got hot-unplugged. Let's exit. */
715 return !port_has_data(port
) && port
->host_connected
;
718 static bool will_write_block(struct port
*port
)
722 if (!port
->guest_connected
) {
723 /* Port got hot-unplugged. Let's exit. */
726 if (!port
->host_connected
)
729 spin_lock_irq(&port
->outvq_lock
);
731 * Check if the Host has consumed any buffers since we last
732 * sent data (this is only applicable for nonblocking ports).
734 reclaim_consumed_buffers(port
);
735 ret
= port
->outvq_full
;
736 spin_unlock_irq(&port
->outvq_lock
);
741 static ssize_t
port_fops_read(struct file
*filp
, char __user
*ubuf
,
742 size_t count
, loff_t
*offp
)
747 port
= filp
->private_data
;
749 if (!port_has_data(port
)) {
751 * If nothing's connected on the host just return 0 in
752 * case of list_empty; this tells the userspace app
753 * that there's no connection
755 if (!port
->host_connected
)
757 if (filp
->f_flags
& O_NONBLOCK
)
760 ret
= wait_event_freezable(port
->waitqueue
,
761 !will_read_block(port
));
765 /* Port got hot-unplugged. */
766 if (!port
->guest_connected
)
769 * We could've received a disconnection message while we were
770 * waiting for more data.
772 * This check is not clubbed in the if() statement above as we
773 * might receive some data as well as the host could get
774 * disconnected after we got woken up from our wait. So we
775 * really want to give off whatever data we have and only then
776 * check for host_connected.
778 if (!port_has_data(port
) && !port
->host_connected
)
781 return fill_readbuf(port
, ubuf
, count
, true);
784 static int wait_port_writable(struct port
*port
, bool nonblock
)
788 if (will_write_block(port
)) {
792 ret
= wait_event_freezable(port
->waitqueue
,
793 !will_write_block(port
));
797 /* Port got hot-unplugged. */
798 if (!port
->guest_connected
)
804 static ssize_t
port_fops_write(struct file
*filp
, const char __user
*ubuf
,
805 size_t count
, loff_t
*offp
)
808 struct port_buffer
*buf
;
811 struct scatterlist sg
[1];
813 /* Userspace could be out to fool us */
817 port
= filp
->private_data
;
819 nonblock
= filp
->f_flags
& O_NONBLOCK
;
821 ret
= wait_port_writable(port
, nonblock
);
825 count
= min((size_t)(32 * 1024), count
);
827 buf
= alloc_buf(port
->out_vq
, count
, 0);
831 ret
= copy_from_user(buf
->buf
, ubuf
, count
);
838 * We now ask send_buf() to not spin for generic ports -- we
839 * can re-use the same code path that non-blocking file
840 * descriptors take for blocking file descriptors since the
841 * wait is already done and we're certain the write will go
842 * through to the host.
845 sg_init_one(sg
, buf
->buf
, count
);
846 ret
= __send_to_port(port
, sg
, 1, count
, buf
, nonblock
);
848 if (nonblock
&& ret
> 0)
861 struct scatterlist
*sg
;
864 static int pipe_to_sg(struct pipe_inode_info
*pipe
, struct pipe_buffer
*buf
,
865 struct splice_desc
*sd
)
867 struct sg_list
*sgl
= sd
->u
.data
;
868 unsigned int offset
, len
;
870 if (sgl
->n
== sgl
->size
)
873 /* Try lock this page */
874 if (buf
->ops
->steal(pipe
, buf
) == 0) {
875 /* Get reference and unlock page for moving */
877 unlock_page(buf
->page
);
879 len
= min(buf
->len
, sd
->len
);
880 sg_set_page(&(sgl
->sg
[sgl
->n
]), buf
->page
, len
, buf
->offset
);
882 /* Failback to copying a page */
883 struct page
*page
= alloc_page(GFP_KERNEL
);
884 char *src
= buf
->ops
->map(pipe
, buf
, 1);
891 offset
= sd
->pos
& ~PAGE_MASK
;
894 if (len
+ offset
> PAGE_SIZE
)
895 len
= PAGE_SIZE
- offset
;
897 memcpy(dst
+ offset
, src
+ buf
->offset
, len
);
900 buf
->ops
->unmap(pipe
, buf
, src
);
902 sg_set_page(&(sgl
->sg
[sgl
->n
]), page
, len
, offset
);
910 /* Faster zero-copy write by splicing */
911 static ssize_t
port_fops_splice_write(struct pipe_inode_info
*pipe
,
912 struct file
*filp
, loff_t
*ppos
,
913 size_t len
, unsigned int flags
)
915 struct port
*port
= filp
->private_data
;
918 struct port_buffer
*buf
;
919 struct splice_desc sd
= {
927 * Rproc_serial does not yet support splice. To support splice
928 * pipe_to_sg() must allocate dma-buffers and copy content from
929 * regular pages to dma pages. And alloc_buf and free_buf must
930 * support allocating and freeing such a list of dma-buffers.
932 if (is_rproc_serial(port
->out_vq
->vdev
))
935 ret
= wait_port_writable(port
, filp
->f_flags
& O_NONBLOCK
);
939 buf
= alloc_buf(port
->out_vq
, 0, pipe
->nrbufs
);
945 sgl
.size
= pipe
->nrbufs
;
947 sg_init_table(sgl
.sg
, sgl
.size
);
948 ret
= __splice_from_pipe(pipe
, &sd
, pipe_to_sg
);
950 ret
= __send_to_port(port
, buf
->sg
, sgl
.n
, sgl
.len
, buf
, true);
952 if (unlikely(ret
<= 0))
957 static unsigned int port_fops_poll(struct file
*filp
, poll_table
*wait
)
962 port
= filp
->private_data
;
963 poll_wait(filp
, &port
->waitqueue
, wait
);
965 if (!port
->guest_connected
) {
966 /* Port got unplugged */
970 if (!will_read_block(port
))
971 ret
|= POLLIN
| POLLRDNORM
;
972 if (!will_write_block(port
))
974 if (!port
->host_connected
)
980 static void remove_port(struct kref
*kref
);
982 static int port_fops_release(struct inode
*inode
, struct file
*filp
)
986 port
= filp
->private_data
;
988 /* Notify host of port being closed */
989 send_control_msg(port
, VIRTIO_CONSOLE_PORT_OPEN
, 0);
991 spin_lock_irq(&port
->inbuf_lock
);
992 port
->guest_connected
= false;
994 discard_port_data(port
);
996 spin_unlock_irq(&port
->inbuf_lock
);
998 spin_lock_irq(&port
->outvq_lock
);
999 reclaim_consumed_buffers(port
);
1000 spin_unlock_irq(&port
->outvq_lock
);
1004 * Locks aren't necessary here as a port can't be opened after
1005 * unplug, and if a port isn't unplugged, a kref would already
1006 * exist for the port. Plus, taking ports_lock here would
1007 * create a dependency on other locks taken by functions
1008 * inside remove_port if we're the last holder of the port,
1009 * creating many problems.
1011 kref_put(&port
->kref
, remove_port
);
1016 static int port_fops_open(struct inode
*inode
, struct file
*filp
)
1018 struct cdev
*cdev
= inode
->i_cdev
;
1022 port
= find_port_by_devt(cdev
->dev
);
1023 filp
->private_data
= port
;
1025 /* Prevent against a port getting hot-unplugged at the same time */
1026 spin_lock_irq(&port
->portdev
->ports_lock
);
1027 kref_get(&port
->kref
);
1028 spin_unlock_irq(&port
->portdev
->ports_lock
);
1031 * Don't allow opening of console port devices -- that's done
1034 if (is_console_port(port
)) {
1039 /* Allow only one process to open a particular port at a time */
1040 spin_lock_irq(&port
->inbuf_lock
);
1041 if (port
->guest_connected
) {
1042 spin_unlock_irq(&port
->inbuf_lock
);
1047 port
->guest_connected
= true;
1048 spin_unlock_irq(&port
->inbuf_lock
);
1050 spin_lock_irq(&port
->outvq_lock
);
1052 * There might be a chance that we missed reclaiming a few
1053 * buffers in the window of the port getting previously closed
1056 reclaim_consumed_buffers(port
);
1057 spin_unlock_irq(&port
->outvq_lock
);
1059 nonseekable_open(inode
, filp
);
1061 /* Notify host of port being opened */
1062 send_control_msg(filp
->private_data
, VIRTIO_CONSOLE_PORT_OPEN
, 1);
1066 kref_put(&port
->kref
, remove_port
);
1070 static int port_fops_fasync(int fd
, struct file
*filp
, int mode
)
1074 port
= filp
->private_data
;
1075 return fasync_helper(fd
, filp
, mode
, &port
->async_queue
);
1079 * The file operations that we support: programs in the guest can open
1080 * a console device, read from it, write to it, poll for data and
1081 * close it. The devices are at
1082 * /dev/vport<device number>p<port number>
1084 static const struct file_operations port_fops
= {
1085 .owner
= THIS_MODULE
,
1086 .open
= port_fops_open
,
1087 .read
= port_fops_read
,
1088 .write
= port_fops_write
,
1089 .splice_write
= port_fops_splice_write
,
1090 .poll
= port_fops_poll
,
1091 .release
= port_fops_release
,
1092 .fasync
= port_fops_fasync
,
1093 .llseek
= no_llseek
,
1097 * The put_chars() callback is pretty straightforward.
1099 * We turn the characters into a scatter-gather list, add it to the
1100 * output queue and then kick the Host. Then we sit here waiting for
1101 * it to finish: inefficient in theory, but in practice
1102 * implementations will do it immediately (lguest's Launcher does).
1104 static int put_chars(u32 vtermno
, const char *buf
, int count
)
1107 struct scatterlist sg
[1];
1109 if (unlikely(early_put_chars
))
1110 return early_put_chars(vtermno
, buf
, count
);
1112 port
= find_port_by_vtermno(vtermno
);
1116 sg_init_one(sg
, buf
, count
);
1117 return __send_to_port(port
, sg
, 1, count
, (void *)buf
, false);
1121 * get_chars() is the callback from the hvc_console infrastructure
1122 * when an interrupt is received.
1124 * We call out to fill_readbuf that gets us the required data from the
1125 * buffers that are queued up.
1127 static int get_chars(u32 vtermno
, char *buf
, int count
)
1131 /* If we've not set up the port yet, we have no input to give. */
1132 if (unlikely(early_put_chars
))
1135 port
= find_port_by_vtermno(vtermno
);
1139 /* If we don't have an input queue yet, we can't get input. */
1140 BUG_ON(!port
->in_vq
);
1142 return fill_readbuf(port
, buf
, count
, false);
1145 static void resize_console(struct port
*port
)
1147 struct virtio_device
*vdev
;
1149 /* The port could have been hot-unplugged */
1150 if (!port
|| !is_console_port(port
))
1153 vdev
= port
->portdev
->vdev
;
1155 /* Don't test F_SIZE at all if we're rproc: not a valid feature! */
1156 if (!is_rproc_serial(vdev
) &&
1157 virtio_has_feature(vdev
, VIRTIO_CONSOLE_F_SIZE
))
1158 hvc_resize(port
->cons
.hvc
, port
->cons
.ws
);
1161 /* We set the configuration at this point, since we now have a tty */
1162 static int notifier_add_vio(struct hvc_struct
*hp
, int data
)
1166 port
= find_port_by_vtermno(hp
->vtermno
);
1170 hp
->irq_requested
= 1;
1171 resize_console(port
);
1176 static void notifier_del_vio(struct hvc_struct
*hp
, int data
)
1178 hp
->irq_requested
= 0;
1181 /* The operations for console ports. */
1182 static const struct hv_ops hv_ops
= {
1183 .get_chars
= get_chars
,
1184 .put_chars
= put_chars
,
1185 .notifier_add
= notifier_add_vio
,
1186 .notifier_del
= notifier_del_vio
,
1187 .notifier_hangup
= notifier_del_vio
,
1191 * Console drivers are initialized very early so boot messages can go
1192 * out, so we do things slightly differently from the generic virtio
1193 * initialization of the net and block drivers.
1195 * At this stage, the console is output-only. It's too early to set
1196 * up a virtqueue, so we let the drivers do some boutique early-output
1199 int __init
virtio_cons_early_init(int (*put_chars
)(u32
, const char *, int))
1201 early_put_chars
= put_chars
;
1202 return hvc_instantiate(0, 0, &hv_ops
);
1205 static int init_port_console(struct port
*port
)
1210 * The Host's telling us this port is a console port. Hook it
1211 * up with an hvc console.
1213 * To set up and manage our virtual console, we call
1216 * The first argument of hvc_alloc() is the virtual console
1217 * number. The second argument is the parameter for the
1218 * notification mechanism (like irq number). We currently
1219 * leave this as zero, virtqueues have implicit notifications.
1221 * The third argument is a "struct hv_ops" containing the
1222 * put_chars() get_chars(), notifier_add() and notifier_del()
1223 * pointers. The final argument is the output buffer size: we
1224 * can do any size, so we put PAGE_SIZE here.
1226 port
->cons
.vtermno
= pdrvdata
.next_vtermno
;
1228 port
->cons
.hvc
= hvc_alloc(port
->cons
.vtermno
, 0, &hv_ops
, PAGE_SIZE
);
1229 if (IS_ERR(port
->cons
.hvc
)) {
1230 ret
= PTR_ERR(port
->cons
.hvc
);
1232 "error %d allocating hvc for port\n", ret
);
1233 port
->cons
.hvc
= NULL
;
1236 spin_lock_irq(&pdrvdata_lock
);
1237 pdrvdata
.next_vtermno
++;
1238 list_add_tail(&port
->cons
.list
, &pdrvdata
.consoles
);
1239 spin_unlock_irq(&pdrvdata_lock
);
1240 port
->guest_connected
= true;
1243 * Start using the new console output if this is the first
1244 * console to come up.
1246 if (early_put_chars
)
1247 early_put_chars
= NULL
;
1249 /* Notify host of port being opened */
1250 send_control_msg(port
, VIRTIO_CONSOLE_PORT_OPEN
, 1);
1255 static ssize_t
show_port_name(struct device
*dev
,
1256 struct device_attribute
*attr
, char *buffer
)
1260 port
= dev_get_drvdata(dev
);
1262 return sprintf(buffer
, "%s\n", port
->name
);
1265 static DEVICE_ATTR(name
, S_IRUGO
, show_port_name
, NULL
);
1267 static struct attribute
*port_sysfs_entries
[] = {
1268 &dev_attr_name
.attr
,
1272 static struct attribute_group port_attribute_group
= {
1273 .name
= NULL
, /* put in device directory */
1274 .attrs
= port_sysfs_entries
,
1277 static ssize_t
debugfs_read(struct file
*filp
, char __user
*ubuf
,
1278 size_t count
, loff_t
*offp
)
1282 ssize_t ret
, out_offset
, out_count
;
1285 buf
= kmalloc(out_count
, GFP_KERNEL
);
1289 port
= filp
->private_data
;
1291 out_offset
+= snprintf(buf
+ out_offset
, out_count
,
1292 "name: %s\n", port
->name
? port
->name
: "");
1293 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1294 "guest_connected: %d\n", port
->guest_connected
);
1295 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1296 "host_connected: %d\n", port
->host_connected
);
1297 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1298 "outvq_full: %d\n", port
->outvq_full
);
1299 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1300 "bytes_sent: %lu\n", port
->stats
.bytes_sent
);
1301 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1302 "bytes_received: %lu\n",
1303 port
->stats
.bytes_received
);
1304 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1305 "bytes_discarded: %lu\n",
1306 port
->stats
.bytes_discarded
);
1307 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1309 is_console_port(port
) ? "yes" : "no");
1310 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
1311 "console_vtermno: %u\n", port
->cons
.vtermno
);
1313 ret
= simple_read_from_buffer(ubuf
, count
, offp
, buf
, out_offset
);
1318 static const struct file_operations port_debugfs_ops
= {
1319 .owner
= THIS_MODULE
,
1320 .open
= simple_open
,
1321 .read
= debugfs_read
,
1324 static void set_console_size(struct port
*port
, u16 rows
, u16 cols
)
1326 if (!port
|| !is_console_port(port
))
1329 port
->cons
.ws
.ws_row
= rows
;
1330 port
->cons
.ws
.ws_col
= cols
;
1333 static unsigned int fill_queue(struct virtqueue
*vq
, spinlock_t
*lock
)
1335 struct port_buffer
*buf
;
1336 unsigned int nr_added_bufs
;
1341 buf
= alloc_buf(vq
, PAGE_SIZE
, 0);
1345 spin_lock_irq(lock
);
1346 ret
= add_inbuf(vq
, buf
);
1348 spin_unlock_irq(lock
);
1349 free_buf(buf
, true);
1353 spin_unlock_irq(lock
);
1356 return nr_added_bufs
;
1359 static void send_sigio_to_port(struct port
*port
)
1361 if (port
->async_queue
&& port
->guest_connected
)
1362 kill_fasync(&port
->async_queue
, SIGIO
, POLL_OUT
);
1365 static int add_port(struct ports_device
*portdev
, u32 id
)
1367 char debugfs_name
[16];
1369 struct port_buffer
*buf
;
1371 unsigned int nr_added_bufs
;
1374 port
= kmalloc(sizeof(*port
), GFP_KERNEL
);
1379 kref_init(&port
->kref
);
1381 port
->portdev
= portdev
;
1386 port
->cons
.hvc
= NULL
;
1387 port
->async_queue
= NULL
;
1389 port
->cons
.ws
.ws_row
= port
->cons
.ws
.ws_col
= 0;
1391 port
->host_connected
= port
->guest_connected
= false;
1392 port
->stats
= (struct port_stats
) { 0 };
1394 port
->outvq_full
= false;
1396 port
->in_vq
= portdev
->in_vqs
[port
->id
];
1397 port
->out_vq
= portdev
->out_vqs
[port
->id
];
1399 port
->cdev
= cdev_alloc();
1401 dev_err(&port
->portdev
->vdev
->dev
, "Error allocating cdev\n");
1405 port
->cdev
->ops
= &port_fops
;
1407 devt
= MKDEV(portdev
->chr_major
, id
);
1408 err
= cdev_add(port
->cdev
, devt
, 1);
1410 dev_err(&port
->portdev
->vdev
->dev
,
1411 "Error %d adding cdev for port %u\n", err
, id
);
1414 port
->dev
= device_create(pdrvdata
.class, &port
->portdev
->vdev
->dev
,
1415 devt
, port
, "vport%up%u",
1416 port
->portdev
->vdev
->index
, id
);
1417 if (IS_ERR(port
->dev
)) {
1418 err
= PTR_ERR(port
->dev
);
1419 dev_err(&port
->portdev
->vdev
->dev
,
1420 "Error %d creating device for port %u\n",
1425 spin_lock_init(&port
->inbuf_lock
);
1426 spin_lock_init(&port
->outvq_lock
);
1427 init_waitqueue_head(&port
->waitqueue
);
1429 /* Fill the in_vq with buffers so the host can send us data. */
1430 nr_added_bufs
= fill_queue(port
->in_vq
, &port
->inbuf_lock
);
1431 if (!nr_added_bufs
) {
1432 dev_err(port
->dev
, "Error allocating inbufs\n");
1437 if (is_rproc_serial(port
->portdev
->vdev
))
1439 * For rproc_serial assume remote processor is connected.
1440 * rproc_serial does not want the console port, only
1441 * the generic port implementation.
1443 port
->host_connected
= true;
1444 else if (!use_multiport(port
->portdev
)) {
1446 * If we're not using multiport support,
1447 * this has to be a console port.
1449 err
= init_port_console(port
);
1454 spin_lock_irq(&portdev
->ports_lock
);
1455 list_add_tail(&port
->list
, &port
->portdev
->ports
);
1456 spin_unlock_irq(&portdev
->ports_lock
);
1459 * Tell the Host we're set so that it can send us various
1460 * configuration parameters for this port (eg, port name,
1461 * caching, whether this is a console port, etc.)
1463 send_control_msg(port
, VIRTIO_CONSOLE_PORT_READY
, 1);
1465 if (pdrvdata
.debugfs_dir
) {
1467 * Finally, create the debugfs file that we can use to
1468 * inspect a port's state at any time
1470 sprintf(debugfs_name
, "vport%up%u",
1471 port
->portdev
->vdev
->index
, id
);
1472 port
->debugfs_file
= debugfs_create_file(debugfs_name
, 0444,
1473 pdrvdata
.debugfs_dir
,
1480 while ((buf
= virtqueue_detach_unused_buf(port
->in_vq
)))
1481 free_buf(buf
, true);
1483 device_destroy(pdrvdata
.class, port
->dev
->devt
);
1485 cdev_del(port
->cdev
);
1489 /* The host might want to notify management sw about port add failure */
1490 __send_control_msg(portdev
, id
, VIRTIO_CONSOLE_PORT_READY
, 0);
1494 /* No users remain, remove all port-specific data. */
1495 static void remove_port(struct kref
*kref
)
1499 port
= container_of(kref
, struct port
, kref
);
1501 sysfs_remove_group(&port
->dev
->kobj
, &port_attribute_group
);
1502 device_destroy(pdrvdata
.class, port
->dev
->devt
);
1503 cdev_del(port
->cdev
);
1507 debugfs_remove(port
->debugfs_file
);
1512 static void remove_port_data(struct port
*port
)
1514 struct port_buffer
*buf
;
1516 spin_lock_irq(&port
->inbuf_lock
);
1517 /* Remove unused data this port might have received. */
1518 discard_port_data(port
);
1520 /* Remove buffers we queued up for the Host to send us data in. */
1521 while ((buf
= virtqueue_detach_unused_buf(port
->in_vq
)))
1522 free_buf(buf
, true);
1523 spin_unlock_irq(&port
->inbuf_lock
);
1525 spin_lock_irq(&port
->outvq_lock
);
1526 reclaim_consumed_buffers(port
);
1528 /* Free pending buffers from the out-queue. */
1529 while ((buf
= virtqueue_detach_unused_buf(port
->out_vq
)))
1530 free_buf(buf
, true);
1531 spin_unlock_irq(&port
->outvq_lock
);
1535 * Port got unplugged. Remove port from portdev's list and drop the
1536 * kref reference. If no userspace has this port opened, it will
1537 * result in immediate removal the port.
1539 static void unplug_port(struct port
*port
)
1541 spin_lock_irq(&port
->portdev
->ports_lock
);
1542 list_del(&port
->list
);
1543 spin_unlock_irq(&port
->portdev
->ports_lock
);
1545 if (port
->guest_connected
) {
1546 port
->guest_connected
= false;
1547 port
->host_connected
= false;
1548 wake_up_interruptible(&port
->waitqueue
);
1550 /* Let the app know the port is going down. */
1551 send_sigio_to_port(port
);
1554 if (is_console_port(port
)) {
1555 spin_lock_irq(&pdrvdata_lock
);
1556 list_del(&port
->cons
.list
);
1557 spin_unlock_irq(&pdrvdata_lock
);
1558 hvc_remove(port
->cons
.hvc
);
1561 remove_port_data(port
);
1564 * We should just assume the device itself has gone off --
1565 * else a close on an open port later will try to send out a
1568 port
->portdev
= NULL
;
1571 * Locks around here are not necessary - a port can't be
1572 * opened after we removed the port struct from ports_list
1575 kref_put(&port
->kref
, remove_port
);
1578 /* Any private messages that the Host and Guest want to share */
1579 static void handle_control_message(struct ports_device
*portdev
,
1580 struct port_buffer
*buf
)
1582 struct virtio_console_control
*cpkt
;
1587 cpkt
= (struct virtio_console_control
*)(buf
->buf
+ buf
->offset
);
1589 port
= find_port_by_id(portdev
, cpkt
->id
);
1590 if (!port
&& cpkt
->event
!= VIRTIO_CONSOLE_PORT_ADD
) {
1591 /* No valid header at start of buffer. Drop it. */
1592 dev_dbg(&portdev
->vdev
->dev
,
1593 "Invalid index %u in control packet\n", cpkt
->id
);
1597 switch (cpkt
->event
) {
1598 case VIRTIO_CONSOLE_PORT_ADD
:
1600 dev_dbg(&portdev
->vdev
->dev
,
1601 "Port %u already added\n", port
->id
);
1602 send_control_msg(port
, VIRTIO_CONSOLE_PORT_READY
, 1);
1605 if (cpkt
->id
>= portdev
->config
.max_nr_ports
) {
1606 dev_warn(&portdev
->vdev
->dev
,
1607 "Request for adding port with out-of-bound id %u, max. supported id: %u\n",
1608 cpkt
->id
, portdev
->config
.max_nr_ports
- 1);
1611 add_port(portdev
, cpkt
->id
);
1613 case VIRTIO_CONSOLE_PORT_REMOVE
:
1616 case VIRTIO_CONSOLE_CONSOLE_PORT
:
1619 if (is_console_port(port
))
1622 init_port_console(port
);
1623 complete(&early_console_added
);
1625 * Could remove the port here in case init fails - but
1626 * have to notify the host first.
1629 case VIRTIO_CONSOLE_RESIZE
: {
1635 if (!is_console_port(port
))
1638 memcpy(&size
, buf
->buf
+ buf
->offset
+ sizeof(*cpkt
),
1640 set_console_size(port
, size
.rows
, size
.cols
);
1642 port
->cons
.hvc
->irq_requested
= 1;
1643 resize_console(port
);
1646 case VIRTIO_CONSOLE_PORT_OPEN
:
1647 port
->host_connected
= cpkt
->value
;
1648 wake_up_interruptible(&port
->waitqueue
);
1650 * If the host port got closed and the host had any
1651 * unconsumed buffers, we'll be able to reclaim them
1654 spin_lock_irq(&port
->outvq_lock
);
1655 reclaim_consumed_buffers(port
);
1656 spin_unlock_irq(&port
->outvq_lock
);
1659 * If the guest is connected, it'll be interested in
1660 * knowing the host connection state changed.
1662 send_sigio_to_port(port
);
1664 case VIRTIO_CONSOLE_PORT_NAME
:
1666 * If we woke up after hibernation, we can get this
1667 * again. Skip it in that case.
1673 * Skip the size of the header and the cpkt to get the size
1674 * of the name that was sent
1676 name_size
= buf
->len
- buf
->offset
- sizeof(*cpkt
) + 1;
1678 port
->name
= kmalloc(name_size
, GFP_KERNEL
);
1681 "Not enough space to store port name\n");
1684 strncpy(port
->name
, buf
->buf
+ buf
->offset
+ sizeof(*cpkt
),
1686 port
->name
[name_size
- 1] = 0;
1689 * Since we only have one sysfs attribute, 'name',
1690 * create it only if we have a name for the port.
1692 err
= sysfs_create_group(&port
->dev
->kobj
,
1693 &port_attribute_group
);
1696 "Error %d creating sysfs device attributes\n",
1700 * Generate a udev event so that appropriate
1701 * symlinks can be created based on udev
1704 kobject_uevent(&port
->dev
->kobj
, KOBJ_CHANGE
);
1710 static void control_work_handler(struct work_struct
*work
)
1712 struct ports_device
*portdev
;
1713 struct virtqueue
*vq
;
1714 struct port_buffer
*buf
;
1717 portdev
= container_of(work
, struct ports_device
, control_work
);
1718 vq
= portdev
->c_ivq
;
1720 spin_lock(&portdev
->c_ivq_lock
);
1721 while ((buf
= virtqueue_get_buf(vq
, &len
))) {
1722 spin_unlock(&portdev
->c_ivq_lock
);
1727 handle_control_message(portdev
, buf
);
1729 spin_lock(&portdev
->c_ivq_lock
);
1730 if (add_inbuf(portdev
->c_ivq
, buf
) < 0) {
1731 dev_warn(&portdev
->vdev
->dev
,
1732 "Error adding buffer to queue\n");
1733 free_buf(buf
, false);
1736 spin_unlock(&portdev
->c_ivq_lock
);
1739 static void out_intr(struct virtqueue
*vq
)
1743 port
= find_port_by_vq(vq
->vdev
->priv
, vq
);
1747 wake_up_interruptible(&port
->waitqueue
);
1750 static void in_intr(struct virtqueue
*vq
)
1753 unsigned long flags
;
1755 port
= find_port_by_vq(vq
->vdev
->priv
, vq
);
1759 spin_lock_irqsave(&port
->inbuf_lock
, flags
);
1760 port
->inbuf
= get_inbuf(port
);
1763 * Normally the port should not accept data when the port is
1764 * closed. For generic serial ports, the host won't (shouldn't)
1765 * send data till the guest is connected. But this condition
1766 * can be reached when a console port is not yet connected (no
1767 * tty is spawned) and the other side sends out data over the
1768 * vring, or when a remote devices start sending data before
1769 * the ports are opened.
1771 * A generic serial port will discard data if not connected,
1772 * while console ports and rproc-serial ports accepts data at
1773 * any time. rproc-serial is initiated with guest_connected to
1774 * false because port_fops_open expects this. Console ports are
1775 * hooked up with an HVC console and is initialized with
1776 * guest_connected to true.
1779 if (!port
->guest_connected
&& !is_rproc_serial(port
->portdev
->vdev
))
1780 discard_port_data(port
);
1782 spin_unlock_irqrestore(&port
->inbuf_lock
, flags
);
1784 wake_up_interruptible(&port
->waitqueue
);
1786 /* Send a SIGIO indicating new data in case the process asked for it */
1787 send_sigio_to_port(port
);
1789 if (is_console_port(port
) && hvc_poll(port
->cons
.hvc
))
1793 static void control_intr(struct virtqueue
*vq
)
1795 struct ports_device
*portdev
;
1797 portdev
= vq
->vdev
->priv
;
1798 schedule_work(&portdev
->control_work
);
1801 static void config_intr(struct virtio_device
*vdev
)
1803 struct ports_device
*portdev
;
1805 portdev
= vdev
->priv
;
1807 if (!use_multiport(portdev
)) {
1811 vdev
->config
->get(vdev
,
1812 offsetof(struct virtio_console_config
, cols
),
1813 &cols
, sizeof(u16
));
1814 vdev
->config
->get(vdev
,
1815 offsetof(struct virtio_console_config
, rows
),
1816 &rows
, sizeof(u16
));
1818 port
= find_port_by_id(portdev
, 0);
1819 set_console_size(port
, rows
, cols
);
1822 * We'll use this way of resizing only for legacy
1823 * support. For newer userspace
1824 * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
1825 * to indicate console size changes so that it can be
1828 resize_console(port
);
1832 static int init_vqs(struct ports_device
*portdev
)
1834 vq_callback_t
**io_callbacks
;
1836 struct virtqueue
**vqs
;
1837 u32 i
, j
, nr_ports
, nr_queues
;
1840 nr_ports
= portdev
->config
.max_nr_ports
;
1841 nr_queues
= use_multiport(portdev
) ? (nr_ports
+ 1) * 2 : 2;
1843 vqs
= kmalloc(nr_queues
* sizeof(struct virtqueue
*), GFP_KERNEL
);
1844 io_callbacks
= kmalloc(nr_queues
* sizeof(vq_callback_t
*), GFP_KERNEL
);
1845 io_names
= kmalloc(nr_queues
* sizeof(char *), GFP_KERNEL
);
1846 portdev
->in_vqs
= kmalloc(nr_ports
* sizeof(struct virtqueue
*),
1848 portdev
->out_vqs
= kmalloc(nr_ports
* sizeof(struct virtqueue
*),
1850 if (!vqs
|| !io_callbacks
|| !io_names
|| !portdev
->in_vqs
||
1851 !portdev
->out_vqs
) {
1857 * For backward compat (newer host but older guest), the host
1858 * spawns a console port first and also inits the vqs for port
1862 io_callbacks
[j
] = in_intr
;
1863 io_callbacks
[j
+ 1] = out_intr
;
1864 io_names
[j
] = "input";
1865 io_names
[j
+ 1] = "output";
1868 if (use_multiport(portdev
)) {
1869 io_callbacks
[j
] = control_intr
;
1870 io_callbacks
[j
+ 1] = NULL
;
1871 io_names
[j
] = "control-i";
1872 io_names
[j
+ 1] = "control-o";
1874 for (i
= 1; i
< nr_ports
; i
++) {
1876 io_callbacks
[j
] = in_intr
;
1877 io_callbacks
[j
+ 1] = out_intr
;
1878 io_names
[j
] = "input";
1879 io_names
[j
+ 1] = "output";
1882 /* Find the queues. */
1883 err
= portdev
->vdev
->config
->find_vqs(portdev
->vdev
, nr_queues
, vqs
,
1885 (const char **)io_names
);
1890 portdev
->in_vqs
[0] = vqs
[0];
1891 portdev
->out_vqs
[0] = vqs
[1];
1893 if (use_multiport(portdev
)) {
1894 portdev
->c_ivq
= vqs
[j
];
1895 portdev
->c_ovq
= vqs
[j
+ 1];
1897 for (i
= 1; i
< nr_ports
; i
++) {
1899 portdev
->in_vqs
[i
] = vqs
[j
];
1900 portdev
->out_vqs
[i
] = vqs
[j
+ 1];
1904 kfree(io_callbacks
);
1910 kfree(portdev
->out_vqs
);
1911 kfree(portdev
->in_vqs
);
1913 kfree(io_callbacks
);
1919 static const struct file_operations portdev_fops
= {
1920 .owner
= THIS_MODULE
,
1923 static void remove_vqs(struct ports_device
*portdev
)
1925 portdev
->vdev
->config
->del_vqs(portdev
->vdev
);
1926 kfree(portdev
->in_vqs
);
1927 kfree(portdev
->out_vqs
);
1930 static void remove_controlq_data(struct ports_device
*portdev
)
1932 struct port_buffer
*buf
;
1935 if (!use_multiport(portdev
))
1938 while ((buf
= virtqueue_get_buf(portdev
->c_ivq
, &len
)))
1939 free_buf(buf
, true);
1941 while ((buf
= virtqueue_detach_unused_buf(portdev
->c_ivq
)))
1942 free_buf(buf
, true);
1946 * Once we're further in boot, we get probed like any other virtio
1949 * If the host also supports multiple console ports, we check the
1950 * config space to see how many ports the host has spawned. We
1951 * initialize each port found.
1953 static int virtcons_probe(struct virtio_device
*vdev
)
1955 struct ports_device
*portdev
;
1958 bool early
= early_put_chars
!= NULL
;
1960 /* Ensure to read early_put_chars now */
1963 portdev
= kmalloc(sizeof(*portdev
), GFP_KERNEL
);
1969 /* Attach this portdev to this virtio_device, and vice-versa. */
1970 portdev
->vdev
= vdev
;
1971 vdev
->priv
= portdev
;
1973 portdev
->chr_major
= register_chrdev(0, "virtio-portsdev",
1975 if (portdev
->chr_major
< 0) {
1977 "Error %d registering chrdev for device %u\n",
1978 portdev
->chr_major
, vdev
->index
);
1979 err
= portdev
->chr_major
;
1984 portdev
->config
.max_nr_ports
= 1;
1986 /* Don't test MULTIPORT at all if we're rproc: not a valid feature! */
1987 if (!is_rproc_serial(vdev
) &&
1988 virtio_config_val(vdev
, VIRTIO_CONSOLE_F_MULTIPORT
,
1989 offsetof(struct virtio_console_config
,
1991 &portdev
->config
.max_nr_ports
) == 0) {
1995 err
= init_vqs(portdev
);
1997 dev_err(&vdev
->dev
, "Error %d initializing vqs\n", err
);
2001 spin_lock_init(&portdev
->ports_lock
);
2002 INIT_LIST_HEAD(&portdev
->ports
);
2005 unsigned int nr_added_bufs
;
2007 spin_lock_init(&portdev
->c_ivq_lock
);
2008 spin_lock_init(&portdev
->c_ovq_lock
);
2009 INIT_WORK(&portdev
->control_work
, &control_work_handler
);
2011 nr_added_bufs
= fill_queue(portdev
->c_ivq
,
2012 &portdev
->c_ivq_lock
);
2013 if (!nr_added_bufs
) {
2015 "Error allocating buffers for control queue\n");
2021 * For backward compatibility: Create a console port
2022 * if we're running on older host.
2024 add_port(portdev
, 0);
2027 spin_lock_irq(&pdrvdata_lock
);
2028 list_add_tail(&portdev
->list
, &pdrvdata
.portdevs
);
2029 spin_unlock_irq(&pdrvdata_lock
);
2031 __send_control_msg(portdev
, VIRTIO_CONSOLE_BAD_ID
,
2032 VIRTIO_CONSOLE_DEVICE_READY
, 1);
2035 * If there was an early virtio console, assume that there are no
2036 * other consoles. We need to wait until the hvc_alloc matches the
2037 * hvc_instantiate, otherwise tty_open will complain, resulting in
2038 * a "Warning: unable to open an initial console" boot failure.
2039 * Without multiport this is done in add_port above. With multiport
2040 * this might take some host<->guest communication - thus we have to
2043 if (multiport
&& early
)
2044 wait_for_completion(&early_console_added
);
2049 /* The host might want to notify mgmt sw about device add failure */
2050 __send_control_msg(portdev
, VIRTIO_CONSOLE_BAD_ID
,
2051 VIRTIO_CONSOLE_DEVICE_READY
, 0);
2052 remove_vqs(portdev
);
2054 unregister_chrdev(portdev
->chr_major
, "virtio-portsdev");
2061 static void virtcons_remove(struct virtio_device
*vdev
)
2063 struct ports_device
*portdev
;
2064 struct port
*port
, *port2
;
2066 portdev
= vdev
->priv
;
2068 spin_lock_irq(&pdrvdata_lock
);
2069 list_del(&portdev
->list
);
2070 spin_unlock_irq(&pdrvdata_lock
);
2072 /* Disable interrupts for vqs */
2073 vdev
->config
->reset(vdev
);
2074 /* Finish up work that's lined up */
2075 if (use_multiport(portdev
))
2076 cancel_work_sync(&portdev
->control_work
);
2078 list_for_each_entry_safe(port
, port2
, &portdev
->ports
, list
)
2081 unregister_chrdev(portdev
->chr_major
, "virtio-portsdev");
2084 * When yanking out a device, we immediately lose the
2085 * (device-side) queues. So there's no point in keeping the
2086 * guest side around till we drop our final reference. This
2087 * also means that any ports which are in an open state will
2088 * have to just stop using the port, as the vqs are going
2091 remove_controlq_data(portdev
);
2092 remove_vqs(portdev
);
2096 static struct virtio_device_id id_table
[] = {
2097 { VIRTIO_ID_CONSOLE
, VIRTIO_DEV_ANY_ID
},
2101 static unsigned int features
[] = {
2102 VIRTIO_CONSOLE_F_SIZE
,
2103 VIRTIO_CONSOLE_F_MULTIPORT
,
2106 static struct virtio_device_id rproc_serial_id_table
[] = {
2107 #if IS_ENABLED(CONFIG_REMOTEPROC)
2108 { VIRTIO_ID_RPROC_SERIAL
, VIRTIO_DEV_ANY_ID
},
2113 static unsigned int rproc_serial_features
[] = {
2117 static int virtcons_freeze(struct virtio_device
*vdev
)
2119 struct ports_device
*portdev
;
2122 portdev
= vdev
->priv
;
2124 vdev
->config
->reset(vdev
);
2126 virtqueue_disable_cb(portdev
->c_ivq
);
2127 cancel_work_sync(&portdev
->control_work
);
2129 * Once more: if control_work_handler() was running, it would
2130 * enable the cb as the last step.
2132 virtqueue_disable_cb(portdev
->c_ivq
);
2133 remove_controlq_data(portdev
);
2135 list_for_each_entry(port
, &portdev
->ports
, list
) {
2136 virtqueue_disable_cb(port
->in_vq
);
2137 virtqueue_disable_cb(port
->out_vq
);
2139 * We'll ask the host later if the new invocation has
2140 * the port opened or closed.
2142 port
->host_connected
= false;
2143 remove_port_data(port
);
2145 remove_vqs(portdev
);
2150 static int virtcons_restore(struct virtio_device
*vdev
)
2152 struct ports_device
*portdev
;
2156 portdev
= vdev
->priv
;
2158 ret
= init_vqs(portdev
);
2162 if (use_multiport(portdev
))
2163 fill_queue(portdev
->c_ivq
, &portdev
->c_ivq_lock
);
2165 list_for_each_entry(port
, &portdev
->ports
, list
) {
2166 port
->in_vq
= portdev
->in_vqs
[port
->id
];
2167 port
->out_vq
= portdev
->out_vqs
[port
->id
];
2169 fill_queue(port
->in_vq
, &port
->inbuf_lock
);
2171 /* Get port open/close status on the host */
2172 send_control_msg(port
, VIRTIO_CONSOLE_PORT_READY
, 1);
2175 * If a port was open at the time of suspending, we
2176 * have to let the host know that it's still open.
2178 if (port
->guest_connected
)
2179 send_control_msg(port
, VIRTIO_CONSOLE_PORT_OPEN
, 1);
2185 static struct virtio_driver virtio_console
= {
2186 .feature_table
= features
,
2187 .feature_table_size
= ARRAY_SIZE(features
),
2188 .driver
.name
= KBUILD_MODNAME
,
2189 .driver
.owner
= THIS_MODULE
,
2190 .id_table
= id_table
,
2191 .probe
= virtcons_probe
,
2192 .remove
= virtcons_remove
,
2193 .config_changed
= config_intr
,
2195 .freeze
= virtcons_freeze
,
2196 .restore
= virtcons_restore
,
2200 static struct virtio_driver virtio_rproc_serial
= {
2201 .feature_table
= rproc_serial_features
,
2202 .feature_table_size
= ARRAY_SIZE(rproc_serial_features
),
2203 .driver
.name
= "virtio_rproc_serial",
2204 .driver
.owner
= THIS_MODULE
,
2205 .id_table
= rproc_serial_id_table
,
2206 .probe
= virtcons_probe
,
2207 .remove
= virtcons_remove
,
2210 static int __init
init(void)
2214 pdrvdata
.class = class_create(THIS_MODULE
, "virtio-ports");
2215 if (IS_ERR(pdrvdata
.class)) {
2216 err
= PTR_ERR(pdrvdata
.class);
2217 pr_err("Error %d creating virtio-ports class\n", err
);
2221 pdrvdata
.debugfs_dir
= debugfs_create_dir("virtio-ports", NULL
);
2222 if (!pdrvdata
.debugfs_dir
) {
2223 pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
2224 PTR_ERR(pdrvdata
.debugfs_dir
));
2226 INIT_LIST_HEAD(&pdrvdata
.consoles
);
2227 INIT_LIST_HEAD(&pdrvdata
.portdevs
);
2229 err
= register_virtio_driver(&virtio_console
);
2231 pr_err("Error %d registering virtio driver\n", err
);
2234 err
= register_virtio_driver(&virtio_rproc_serial
);
2236 pr_err("Error %d registering virtio rproc serial driver\n",
2242 unregister_virtio_driver(&virtio_console
);
2244 if (pdrvdata
.debugfs_dir
)
2245 debugfs_remove_recursive(pdrvdata
.debugfs_dir
);
2246 class_destroy(pdrvdata
.class);
2250 static void __exit
fini(void)
2254 unregister_virtio_driver(&virtio_console
);
2255 unregister_virtio_driver(&virtio_rproc_serial
);
2257 class_destroy(pdrvdata
.class);
2258 if (pdrvdata
.debugfs_dir
)
2259 debugfs_remove_recursive(pdrvdata
.debugfs_dir
);
2264 MODULE_DEVICE_TABLE(virtio
, id_table
);
2265 MODULE_DESCRIPTION("Virtio console driver");
2266 MODULE_LICENSE("GPL");