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If register_virtio_driver() fails, virtio-ports class is not destroyed. The patch adds error handling of register_virtio_driver(). Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1971 lines
47 KiB
C
1971 lines
47 KiB
C
/*
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* Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
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* Copyright (C) 2009, 2010, 2011 Red Hat, Inc.
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* Copyright (C) 2009, 2010, 2011 Amit Shah <amit.shah@redhat.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/cdev.h>
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#include <linux/debugfs.h>
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#include <linux/completion.h>
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/freezer.h>
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#include <linux/fs.h>
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#include <linux/init.h>
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#include <linux/list.h>
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#include <linux/poll.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/virtio.h>
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#include <linux/virtio_console.h>
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#include <linux/wait.h>
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#include <linux/workqueue.h>
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#include <linux/module.h>
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#include "../tty/hvc/hvc_console.h"
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/*
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* This is a global struct for storing common data for all the devices
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* this driver handles.
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*
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* Mainly, it has a linked list for all the consoles in one place so
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* that callbacks from hvc for get_chars(), put_chars() work properly
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* across multiple devices and multiple ports per device.
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*/
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struct ports_driver_data {
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/* Used for registering chardevs */
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struct class *class;
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/* Used for exporting per-port information to debugfs */
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struct dentry *debugfs_dir;
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/* List of all the devices we're handling */
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struct list_head portdevs;
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/* Number of devices this driver is handling */
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unsigned int index;
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/*
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* This is used to keep track of the number of hvc consoles
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* spawned by this driver. This number is given as the first
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* argument to hvc_alloc(). To correctly map an initial
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* console spawned via hvc_instantiate to the console being
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* hooked up via hvc_alloc, we need to pass the same vtermno.
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*
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* We also just assume the first console being initialised was
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* the first one that got used as the initial console.
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*/
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unsigned int next_vtermno;
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/* All the console devices handled by this driver */
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struct list_head consoles;
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};
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static struct ports_driver_data pdrvdata;
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DEFINE_SPINLOCK(pdrvdata_lock);
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DECLARE_COMPLETION(early_console_added);
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/* This struct holds information that's relevant only for console ports */
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struct console {
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/* We'll place all consoles in a list in the pdrvdata struct */
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struct list_head list;
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/* The hvc device associated with this console port */
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struct hvc_struct *hvc;
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/* The size of the console */
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struct winsize ws;
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/*
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* This number identifies the number that we used to register
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* with hvc in hvc_instantiate() and hvc_alloc(); this is the
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* number passed on by the hvc callbacks to us to
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* differentiate between the other console ports handled by
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* this driver
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*/
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u32 vtermno;
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};
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struct port_buffer {
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char *buf;
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/* size of the buffer in *buf above */
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size_t size;
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/* used length of the buffer */
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size_t len;
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/* offset in the buf from which to consume data */
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size_t offset;
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};
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/*
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* This is a per-device struct that stores data common to all the
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* ports for that device (vdev->priv).
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*/
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struct ports_device {
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/* Next portdev in the list, head is in the pdrvdata struct */
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struct list_head list;
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/*
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* Workqueue handlers where we process deferred work after
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* notification
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*/
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struct work_struct control_work;
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struct list_head ports;
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/* To protect the list of ports */
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spinlock_t ports_lock;
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/* To protect the vq operations for the control channel */
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spinlock_t cvq_lock;
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/* The current config space is stored here */
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struct virtio_console_config config;
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/* The virtio device we're associated with */
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struct virtio_device *vdev;
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/*
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* A couple of virtqueues for the control channel: one for
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* guest->host transfers, one for host->guest transfers
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*/
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struct virtqueue *c_ivq, *c_ovq;
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/* Array of per-port IO virtqueues */
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struct virtqueue **in_vqs, **out_vqs;
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/* Used for numbering devices for sysfs and debugfs */
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unsigned int drv_index;
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/* Major number for this device. Ports will be created as minors. */
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int chr_major;
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};
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struct port_stats {
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unsigned long bytes_sent, bytes_received, bytes_discarded;
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};
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/* This struct holds the per-port data */
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struct port {
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/* Next port in the list, head is in the ports_device */
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struct list_head list;
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/* Pointer to the parent virtio_console device */
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struct ports_device *portdev;
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/* The current buffer from which data has to be fed to readers */
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struct port_buffer *inbuf;
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/*
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* To protect the operations on the in_vq associated with this
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* port. Has to be a spinlock because it can be called from
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* interrupt context (get_char()).
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*/
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spinlock_t inbuf_lock;
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/* Protect the operations on the out_vq. */
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spinlock_t outvq_lock;
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/* The IO vqs for this port */
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struct virtqueue *in_vq, *out_vq;
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/* File in the debugfs directory that exposes this port's information */
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struct dentry *debugfs_file;
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/*
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* Keep count of the bytes sent, received and discarded for
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* this port for accounting and debugging purposes. These
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* counts are not reset across port open / close events.
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*/
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struct port_stats stats;
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/*
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* The entries in this struct will be valid if this port is
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* hooked up to an hvc console
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*/
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struct console cons;
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/* Each port associates with a separate char device */
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struct cdev *cdev;
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struct device *dev;
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/* Reference-counting to handle port hot-unplugs and file operations */
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struct kref kref;
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/* A waitqueue for poll() or blocking read operations */
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wait_queue_head_t waitqueue;
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/* The 'name' of the port that we expose via sysfs properties */
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char *name;
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/* We can notify apps of host connect / disconnect events via SIGIO */
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struct fasync_struct *async_queue;
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/* The 'id' to identify the port with the Host */
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u32 id;
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bool outvq_full;
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/* Is the host device open */
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bool host_connected;
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/* We should allow only one process to open a port */
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bool guest_connected;
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};
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/* This is the very early arch-specified put chars function. */
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static int (*early_put_chars)(u32, const char *, int);
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static struct port *find_port_by_vtermno(u32 vtermno)
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{
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struct port *port;
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struct console *cons;
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unsigned long flags;
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spin_lock_irqsave(&pdrvdata_lock, flags);
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list_for_each_entry(cons, &pdrvdata.consoles, list) {
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if (cons->vtermno == vtermno) {
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port = container_of(cons, struct port, cons);
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goto out;
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}
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}
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port = NULL;
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out:
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spin_unlock_irqrestore(&pdrvdata_lock, flags);
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return port;
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}
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static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev,
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dev_t dev)
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{
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struct port *port;
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unsigned long flags;
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spin_lock_irqsave(&portdev->ports_lock, flags);
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list_for_each_entry(port, &portdev->ports, list)
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if (port->cdev->dev == dev)
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goto out;
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port = NULL;
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out:
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spin_unlock_irqrestore(&portdev->ports_lock, flags);
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return port;
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}
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static struct port *find_port_by_devt(dev_t dev)
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{
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struct ports_device *portdev;
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struct port *port;
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unsigned long flags;
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spin_lock_irqsave(&pdrvdata_lock, flags);
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list_for_each_entry(portdev, &pdrvdata.portdevs, list) {
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port = find_port_by_devt_in_portdev(portdev, dev);
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if (port)
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goto out;
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}
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port = NULL;
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out:
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spin_unlock_irqrestore(&pdrvdata_lock, flags);
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return port;
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}
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static struct port *find_port_by_id(struct ports_device *portdev, u32 id)
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{
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struct port *port;
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unsigned long flags;
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spin_lock_irqsave(&portdev->ports_lock, flags);
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list_for_each_entry(port, &portdev->ports, list)
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if (port->id == id)
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goto out;
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port = NULL;
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out:
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spin_unlock_irqrestore(&portdev->ports_lock, flags);
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return port;
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}
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static struct port *find_port_by_vq(struct ports_device *portdev,
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struct virtqueue *vq)
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{
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struct port *port;
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unsigned long flags;
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spin_lock_irqsave(&portdev->ports_lock, flags);
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list_for_each_entry(port, &portdev->ports, list)
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if (port->in_vq == vq || port->out_vq == vq)
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goto out;
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port = NULL;
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out:
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spin_unlock_irqrestore(&portdev->ports_lock, flags);
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return port;
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}
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static bool is_console_port(struct port *port)
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{
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if (port->cons.hvc)
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return true;
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return false;
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}
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static inline bool use_multiport(struct ports_device *portdev)
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{
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/*
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* This condition can be true when put_chars is called from
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* early_init
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*/
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if (!portdev->vdev)
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return 0;
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return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
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}
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static void free_buf(struct port_buffer *buf)
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{
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kfree(buf->buf);
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kfree(buf);
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}
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static struct port_buffer *alloc_buf(size_t buf_size)
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{
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struct port_buffer *buf;
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buf = kmalloc(sizeof(*buf), GFP_KERNEL);
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if (!buf)
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goto fail;
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buf->buf = kzalloc(buf_size, GFP_KERNEL);
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if (!buf->buf)
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goto free_buf;
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buf->len = 0;
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buf->offset = 0;
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buf->size = buf_size;
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return buf;
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free_buf:
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kfree(buf);
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fail:
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return NULL;
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}
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/* Callers should take appropriate locks */
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static struct port_buffer *get_inbuf(struct port *port)
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{
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struct port_buffer *buf;
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unsigned int len;
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if (port->inbuf)
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return port->inbuf;
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buf = virtqueue_get_buf(port->in_vq, &len);
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if (buf) {
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buf->len = len;
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buf->offset = 0;
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port->stats.bytes_received += len;
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}
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return buf;
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}
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/*
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* Create a scatter-gather list representing our input buffer and put
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* it in the queue.
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*
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* Callers should take appropriate locks.
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*/
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static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
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{
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struct scatterlist sg[1];
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int ret;
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sg_init_one(sg, buf->buf, buf->size);
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ret = virtqueue_add_buf(vq, sg, 0, 1, buf, GFP_ATOMIC);
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virtqueue_kick(vq);
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return ret;
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}
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/* Discard any unread data this port has. Callers lockers. */
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static void discard_port_data(struct port *port)
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{
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struct port_buffer *buf;
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unsigned int err;
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if (!port->portdev) {
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/* Device has been unplugged. vqs are already gone. */
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return;
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}
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buf = get_inbuf(port);
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err = 0;
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while (buf) {
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port->stats.bytes_discarded += buf->len - buf->offset;
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if (add_inbuf(port->in_vq, buf) < 0) {
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err++;
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free_buf(buf);
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}
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port->inbuf = NULL;
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buf = get_inbuf(port);
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}
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if (err)
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dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
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err);
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}
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static bool port_has_data(struct port *port)
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{
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unsigned long flags;
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bool ret;
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ret = false;
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spin_lock_irqsave(&port->inbuf_lock, flags);
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port->inbuf = get_inbuf(port);
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if (port->inbuf)
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ret = true;
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spin_unlock_irqrestore(&port->inbuf_lock, flags);
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return ret;
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}
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static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
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unsigned int event, unsigned int value)
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{
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struct scatterlist sg[1];
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struct virtio_console_control cpkt;
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struct virtqueue *vq;
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unsigned int len;
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if (!use_multiport(portdev))
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return 0;
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cpkt.id = port_id;
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cpkt.event = event;
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cpkt.value = value;
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vq = portdev->c_ovq;
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sg_init_one(sg, &cpkt, sizeof(cpkt));
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if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) >= 0) {
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virtqueue_kick(vq);
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while (!virtqueue_get_buf(vq, &len))
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cpu_relax();
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}
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return 0;
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}
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static ssize_t send_control_msg(struct port *port, unsigned int event,
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unsigned int value)
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{
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/* Did the port get unplugged before userspace closed it? */
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if (port->portdev)
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return __send_control_msg(port->portdev, port->id, event, value);
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return 0;
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}
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/* Callers must take the port->outvq_lock */
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static void reclaim_consumed_buffers(struct port *port)
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{
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void *buf;
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unsigned int len;
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if (!port->portdev) {
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/* Device has been unplugged. vqs are already gone. */
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return;
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}
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while ((buf = virtqueue_get_buf(port->out_vq, &len))) {
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kfree(buf);
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port->outvq_full = false;
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}
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}
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static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
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bool nonblock)
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{
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struct scatterlist sg[1];
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struct virtqueue *out_vq;
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ssize_t ret;
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unsigned long flags;
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unsigned int len;
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out_vq = port->out_vq;
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spin_lock_irqsave(&port->outvq_lock, flags);
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reclaim_consumed_buffers(port);
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sg_init_one(sg, in_buf, in_count);
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ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf, GFP_ATOMIC);
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/* Tell Host to go! */
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virtqueue_kick(out_vq);
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if (ret < 0) {
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in_count = 0;
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goto done;
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}
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if (ret == 0)
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port->outvq_full = true;
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if (nonblock)
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goto done;
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/*
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* Wait till the host acknowledges it pushed out the data we
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* sent. This is done for data from the hvc_console; the tty
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* operations are performed with spinlocks held so we can't
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* sleep here. An alternative would be to copy the data to a
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* buffer and relax the spinning requirement. The downside is
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* we need to kmalloc a GFP_ATOMIC buffer each time the
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* console driver writes something out.
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*/
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while (!virtqueue_get_buf(out_vq, &len))
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cpu_relax();
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done:
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spin_unlock_irqrestore(&port->outvq_lock, flags);
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port->stats.bytes_sent += in_count;
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/*
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* We're expected to return the amount of data we wrote -- all
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* of it
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*/
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return in_count;
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}
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/*
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* Give out the data that's requested from the buffer that we have
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* queued up.
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*/
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static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count,
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bool to_user)
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{
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struct port_buffer *buf;
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unsigned long flags;
|
|
|
|
if (!out_count || !port_has_data(port))
|
|
return 0;
|
|
|
|
buf = port->inbuf;
|
|
out_count = min(out_count, buf->len - buf->offset);
|
|
|
|
if (to_user) {
|
|
ssize_t ret;
|
|
|
|
ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count);
|
|
if (ret)
|
|
return -EFAULT;
|
|
} else {
|
|
memcpy(out_buf, buf->buf + buf->offset, out_count);
|
|
}
|
|
|
|
buf->offset += out_count;
|
|
|
|
if (buf->offset == buf->len) {
|
|
/*
|
|
* We're done using all the data in this buffer.
|
|
* Re-queue so that the Host can send us more data.
|
|
*/
|
|
spin_lock_irqsave(&port->inbuf_lock, flags);
|
|
port->inbuf = NULL;
|
|
|
|
if (add_inbuf(port->in_vq, buf) < 0)
|
|
dev_warn(port->dev, "failed add_buf\n");
|
|
|
|
spin_unlock_irqrestore(&port->inbuf_lock, flags);
|
|
}
|
|
/* Return the number of bytes actually copied */
|
|
return out_count;
|
|
}
|
|
|
|
/* The condition that must be true for polling to end */
|
|
static bool will_read_block(struct port *port)
|
|
{
|
|
if (!port->guest_connected) {
|
|
/* Port got hot-unplugged. Let's exit. */
|
|
return false;
|
|
}
|
|
return !port_has_data(port) && port->host_connected;
|
|
}
|
|
|
|
static bool will_write_block(struct port *port)
|
|
{
|
|
bool ret;
|
|
|
|
if (!port->guest_connected) {
|
|
/* Port got hot-unplugged. Let's exit. */
|
|
return false;
|
|
}
|
|
if (!port->host_connected)
|
|
return true;
|
|
|
|
spin_lock_irq(&port->outvq_lock);
|
|
/*
|
|
* Check if the Host has consumed any buffers since we last
|
|
* sent data (this is only applicable for nonblocking ports).
|
|
*/
|
|
reclaim_consumed_buffers(port);
|
|
ret = port->outvq_full;
|
|
spin_unlock_irq(&port->outvq_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
|
|
size_t count, loff_t *offp)
|
|
{
|
|
struct port *port;
|
|
ssize_t ret;
|
|
|
|
port = filp->private_data;
|
|
|
|
if (!port_has_data(port)) {
|
|
/*
|
|
* If nothing's connected on the host just return 0 in
|
|
* case of list_empty; this tells the userspace app
|
|
* that there's no connection
|
|
*/
|
|
if (!port->host_connected)
|
|
return 0;
|
|
if (filp->f_flags & O_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
ret = wait_event_freezable(port->waitqueue,
|
|
!will_read_block(port));
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
/* Port got hot-unplugged. */
|
|
if (!port->guest_connected)
|
|
return -ENODEV;
|
|
/*
|
|
* We could've received a disconnection message while we were
|
|
* waiting for more data.
|
|
*
|
|
* This check is not clubbed in the if() statement above as we
|
|
* might receive some data as well as the host could get
|
|
* disconnected after we got woken up from our wait. So we
|
|
* really want to give off whatever data we have and only then
|
|
* check for host_connected.
|
|
*/
|
|
if (!port_has_data(port) && !port->host_connected)
|
|
return 0;
|
|
|
|
return fill_readbuf(port, ubuf, count, true);
|
|
}
|
|
|
|
static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
|
|
size_t count, loff_t *offp)
|
|
{
|
|
struct port *port;
|
|
char *buf;
|
|
ssize_t ret;
|
|
bool nonblock;
|
|
|
|
/* Userspace could be out to fool us */
|
|
if (!count)
|
|
return 0;
|
|
|
|
port = filp->private_data;
|
|
|
|
nonblock = filp->f_flags & O_NONBLOCK;
|
|
|
|
if (will_write_block(port)) {
|
|
if (nonblock)
|
|
return -EAGAIN;
|
|
|
|
ret = wait_event_freezable(port->waitqueue,
|
|
!will_write_block(port));
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
/* Port got hot-unplugged. */
|
|
if (!port->guest_connected)
|
|
return -ENODEV;
|
|
|
|
count = min((size_t)(32 * 1024), count);
|
|
|
|
buf = kmalloc(count, GFP_KERNEL);
|
|
if (!buf)
|
|
return -ENOMEM;
|
|
|
|
ret = copy_from_user(buf, ubuf, count);
|
|
if (ret) {
|
|
ret = -EFAULT;
|
|
goto free_buf;
|
|
}
|
|
|
|
/*
|
|
* We now ask send_buf() to not spin for generic ports -- we
|
|
* can re-use the same code path that non-blocking file
|
|
* descriptors take for blocking file descriptors since the
|
|
* wait is already done and we're certain the write will go
|
|
* through to the host.
|
|
*/
|
|
nonblock = true;
|
|
ret = send_buf(port, buf, count, nonblock);
|
|
|
|
if (nonblock && ret > 0)
|
|
goto out;
|
|
|
|
free_buf:
|
|
kfree(buf);
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
|
|
{
|
|
struct port *port;
|
|
unsigned int ret;
|
|
|
|
port = filp->private_data;
|
|
poll_wait(filp, &port->waitqueue, wait);
|
|
|
|
if (!port->guest_connected) {
|
|
/* Port got unplugged */
|
|
return POLLHUP;
|
|
}
|
|
ret = 0;
|
|
if (!will_read_block(port))
|
|
ret |= POLLIN | POLLRDNORM;
|
|
if (!will_write_block(port))
|
|
ret |= POLLOUT;
|
|
if (!port->host_connected)
|
|
ret |= POLLHUP;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void remove_port(struct kref *kref);
|
|
|
|
static int port_fops_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct port *port;
|
|
|
|
port = filp->private_data;
|
|
|
|
/* Notify host of port being closed */
|
|
send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
|
|
|
|
spin_lock_irq(&port->inbuf_lock);
|
|
port->guest_connected = false;
|
|
|
|
discard_port_data(port);
|
|
|
|
spin_unlock_irq(&port->inbuf_lock);
|
|
|
|
spin_lock_irq(&port->outvq_lock);
|
|
reclaim_consumed_buffers(port);
|
|
spin_unlock_irq(&port->outvq_lock);
|
|
|
|
/*
|
|
* Locks aren't necessary here as a port can't be opened after
|
|
* unplug, and if a port isn't unplugged, a kref would already
|
|
* exist for the port. Plus, taking ports_lock here would
|
|
* create a dependency on other locks taken by functions
|
|
* inside remove_port if we're the last holder of the port,
|
|
* creating many problems.
|
|
*/
|
|
kref_put(&port->kref, remove_port);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int port_fops_open(struct inode *inode, struct file *filp)
|
|
{
|
|
struct cdev *cdev = inode->i_cdev;
|
|
struct port *port;
|
|
int ret;
|
|
|
|
port = find_port_by_devt(cdev->dev);
|
|
filp->private_data = port;
|
|
|
|
/* Prevent against a port getting hot-unplugged at the same time */
|
|
spin_lock_irq(&port->portdev->ports_lock);
|
|
kref_get(&port->kref);
|
|
spin_unlock_irq(&port->portdev->ports_lock);
|
|
|
|
/*
|
|
* Don't allow opening of console port devices -- that's done
|
|
* via /dev/hvc
|
|
*/
|
|
if (is_console_port(port)) {
|
|
ret = -ENXIO;
|
|
goto out;
|
|
}
|
|
|
|
/* Allow only one process to open a particular port at a time */
|
|
spin_lock_irq(&port->inbuf_lock);
|
|
if (port->guest_connected) {
|
|
spin_unlock_irq(&port->inbuf_lock);
|
|
ret = -EMFILE;
|
|
goto out;
|
|
}
|
|
|
|
port->guest_connected = true;
|
|
spin_unlock_irq(&port->inbuf_lock);
|
|
|
|
spin_lock_irq(&port->outvq_lock);
|
|
/*
|
|
* There might be a chance that we missed reclaiming a few
|
|
* buffers in the window of the port getting previously closed
|
|
* and opening now.
|
|
*/
|
|
reclaim_consumed_buffers(port);
|
|
spin_unlock_irq(&port->outvq_lock);
|
|
|
|
nonseekable_open(inode, filp);
|
|
|
|
/* Notify host of port being opened */
|
|
send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
|
|
|
|
return 0;
|
|
out:
|
|
kref_put(&port->kref, remove_port);
|
|
return ret;
|
|
}
|
|
|
|
static int port_fops_fasync(int fd, struct file *filp, int mode)
|
|
{
|
|
struct port *port;
|
|
|
|
port = filp->private_data;
|
|
return fasync_helper(fd, filp, mode, &port->async_queue);
|
|
}
|
|
|
|
/*
|
|
* The file operations that we support: programs in the guest can open
|
|
* a console device, read from it, write to it, poll for data and
|
|
* close it. The devices are at
|
|
* /dev/vport<device number>p<port number>
|
|
*/
|
|
static const struct file_operations port_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = port_fops_open,
|
|
.read = port_fops_read,
|
|
.write = port_fops_write,
|
|
.poll = port_fops_poll,
|
|
.release = port_fops_release,
|
|
.fasync = port_fops_fasync,
|
|
.llseek = no_llseek,
|
|
};
|
|
|
|
/*
|
|
* The put_chars() callback is pretty straightforward.
|
|
*
|
|
* We turn the characters into a scatter-gather list, add it to the
|
|
* output queue and then kick the Host. Then we sit here waiting for
|
|
* it to finish: inefficient in theory, but in practice
|
|
* implementations will do it immediately (lguest's Launcher does).
|
|
*/
|
|
static int put_chars(u32 vtermno, const char *buf, int count)
|
|
{
|
|
struct port *port;
|
|
|
|
if (unlikely(early_put_chars))
|
|
return early_put_chars(vtermno, buf, count);
|
|
|
|
port = find_port_by_vtermno(vtermno);
|
|
if (!port)
|
|
return -EPIPE;
|
|
|
|
return send_buf(port, (void *)buf, count, false);
|
|
}
|
|
|
|
/*
|
|
* get_chars() is the callback from the hvc_console infrastructure
|
|
* when an interrupt is received.
|
|
*
|
|
* We call out to fill_readbuf that gets us the required data from the
|
|
* buffers that are queued up.
|
|
*/
|
|
static int get_chars(u32 vtermno, char *buf, int count)
|
|
{
|
|
struct port *port;
|
|
|
|
/* If we've not set up the port yet, we have no input to give. */
|
|
if (unlikely(early_put_chars))
|
|
return 0;
|
|
|
|
port = find_port_by_vtermno(vtermno);
|
|
if (!port)
|
|
return -EPIPE;
|
|
|
|
/* If we don't have an input queue yet, we can't get input. */
|
|
BUG_ON(!port->in_vq);
|
|
|
|
return fill_readbuf(port, buf, count, false);
|
|
}
|
|
|
|
static void resize_console(struct port *port)
|
|
{
|
|
struct virtio_device *vdev;
|
|
|
|
/* The port could have been hot-unplugged */
|
|
if (!port || !is_console_port(port))
|
|
return;
|
|
|
|
vdev = port->portdev->vdev;
|
|
if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
|
|
hvc_resize(port->cons.hvc, port->cons.ws);
|
|
}
|
|
|
|
/* We set the configuration at this point, since we now have a tty */
|
|
static int notifier_add_vio(struct hvc_struct *hp, int data)
|
|
{
|
|
struct port *port;
|
|
|
|
port = find_port_by_vtermno(hp->vtermno);
|
|
if (!port)
|
|
return -EINVAL;
|
|
|
|
hp->irq_requested = 1;
|
|
resize_console(port);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void notifier_del_vio(struct hvc_struct *hp, int data)
|
|
{
|
|
hp->irq_requested = 0;
|
|
}
|
|
|
|
/* The operations for console ports. */
|
|
static const struct hv_ops hv_ops = {
|
|
.get_chars = get_chars,
|
|
.put_chars = put_chars,
|
|
.notifier_add = notifier_add_vio,
|
|
.notifier_del = notifier_del_vio,
|
|
.notifier_hangup = notifier_del_vio,
|
|
};
|
|
|
|
/*
|
|
* Console drivers are initialized very early so boot messages can go
|
|
* out, so we do things slightly differently from the generic virtio
|
|
* initialization of the net and block drivers.
|
|
*
|
|
* At this stage, the console is output-only. It's too early to set
|
|
* up a virtqueue, so we let the drivers do some boutique early-output
|
|
* thing.
|
|
*/
|
|
int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
|
|
{
|
|
early_put_chars = put_chars;
|
|
return hvc_instantiate(0, 0, &hv_ops);
|
|
}
|
|
|
|
int init_port_console(struct port *port)
|
|
{
|
|
int ret;
|
|
|
|
/*
|
|
* The Host's telling us this port is a console port. Hook it
|
|
* up with an hvc console.
|
|
*
|
|
* To set up and manage our virtual console, we call
|
|
* hvc_alloc().
|
|
*
|
|
* The first argument of hvc_alloc() is the virtual console
|
|
* number. The second argument is the parameter for the
|
|
* notification mechanism (like irq number). We currently
|
|
* leave this as zero, virtqueues have implicit notifications.
|
|
*
|
|
* The third argument is a "struct hv_ops" containing the
|
|
* put_chars() get_chars(), notifier_add() and notifier_del()
|
|
* pointers. The final argument is the output buffer size: we
|
|
* can do any size, so we put PAGE_SIZE here.
|
|
*/
|
|
port->cons.vtermno = pdrvdata.next_vtermno;
|
|
|
|
port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
|
|
if (IS_ERR(port->cons.hvc)) {
|
|
ret = PTR_ERR(port->cons.hvc);
|
|
dev_err(port->dev,
|
|
"error %d allocating hvc for port\n", ret);
|
|
port->cons.hvc = NULL;
|
|
return ret;
|
|
}
|
|
spin_lock_irq(&pdrvdata_lock);
|
|
pdrvdata.next_vtermno++;
|
|
list_add_tail(&port->cons.list, &pdrvdata.consoles);
|
|
spin_unlock_irq(&pdrvdata_lock);
|
|
port->guest_connected = true;
|
|
|
|
/*
|
|
* Start using the new console output if this is the first
|
|
* console to come up.
|
|
*/
|
|
if (early_put_chars)
|
|
early_put_chars = NULL;
|
|
|
|
/* Notify host of port being opened */
|
|
send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t show_port_name(struct device *dev,
|
|
struct device_attribute *attr, char *buffer)
|
|
{
|
|
struct port *port;
|
|
|
|
port = dev_get_drvdata(dev);
|
|
|
|
return sprintf(buffer, "%s\n", port->name);
|
|
}
|
|
|
|
static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL);
|
|
|
|
static struct attribute *port_sysfs_entries[] = {
|
|
&dev_attr_name.attr,
|
|
NULL
|
|
};
|
|
|
|
static struct attribute_group port_attribute_group = {
|
|
.name = NULL, /* put in device directory */
|
|
.attrs = port_sysfs_entries,
|
|
};
|
|
|
|
static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
|
|
size_t count, loff_t *offp)
|
|
{
|
|
struct port *port;
|
|
char *buf;
|
|
ssize_t ret, out_offset, out_count;
|
|
|
|
out_count = 1024;
|
|
buf = kmalloc(out_count, GFP_KERNEL);
|
|
if (!buf)
|
|
return -ENOMEM;
|
|
|
|
port = filp->private_data;
|
|
out_offset = 0;
|
|
out_offset += snprintf(buf + out_offset, out_count,
|
|
"name: %s\n", port->name ? port->name : "");
|
|
out_offset += snprintf(buf + out_offset, out_count - out_offset,
|
|
"guest_connected: %d\n", port->guest_connected);
|
|
out_offset += snprintf(buf + out_offset, out_count - out_offset,
|
|
"host_connected: %d\n", port->host_connected);
|
|
out_offset += snprintf(buf + out_offset, out_count - out_offset,
|
|
"outvq_full: %d\n", port->outvq_full);
|
|
out_offset += snprintf(buf + out_offset, out_count - out_offset,
|
|
"bytes_sent: %lu\n", port->stats.bytes_sent);
|
|
out_offset += snprintf(buf + out_offset, out_count - out_offset,
|
|
"bytes_received: %lu\n",
|
|
port->stats.bytes_received);
|
|
out_offset += snprintf(buf + out_offset, out_count - out_offset,
|
|
"bytes_discarded: %lu\n",
|
|
port->stats.bytes_discarded);
|
|
out_offset += snprintf(buf + out_offset, out_count - out_offset,
|
|
"is_console: %s\n",
|
|
is_console_port(port) ? "yes" : "no");
|
|
out_offset += snprintf(buf + out_offset, out_count - out_offset,
|
|
"console_vtermno: %u\n", port->cons.vtermno);
|
|
|
|
ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
|
|
kfree(buf);
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations port_debugfs_ops = {
|
|
.owner = THIS_MODULE,
|
|
.open = simple_open,
|
|
.read = debugfs_read,
|
|
};
|
|
|
|
static void set_console_size(struct port *port, u16 rows, u16 cols)
|
|
{
|
|
if (!port || !is_console_port(port))
|
|
return;
|
|
|
|
port->cons.ws.ws_row = rows;
|
|
port->cons.ws.ws_col = cols;
|
|
}
|
|
|
|
static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
|
|
{
|
|
struct port_buffer *buf;
|
|
unsigned int nr_added_bufs;
|
|
int ret;
|
|
|
|
nr_added_bufs = 0;
|
|
do {
|
|
buf = alloc_buf(PAGE_SIZE);
|
|
if (!buf)
|
|
break;
|
|
|
|
spin_lock_irq(lock);
|
|
ret = add_inbuf(vq, buf);
|
|
if (ret < 0) {
|
|
spin_unlock_irq(lock);
|
|
free_buf(buf);
|
|
break;
|
|
}
|
|
nr_added_bufs++;
|
|
spin_unlock_irq(lock);
|
|
} while (ret > 0);
|
|
|
|
return nr_added_bufs;
|
|
}
|
|
|
|
static void send_sigio_to_port(struct port *port)
|
|
{
|
|
if (port->async_queue && port->guest_connected)
|
|
kill_fasync(&port->async_queue, SIGIO, POLL_OUT);
|
|
}
|
|
|
|
static int add_port(struct ports_device *portdev, u32 id)
|
|
{
|
|
char debugfs_name[16];
|
|
struct port *port;
|
|
struct port_buffer *buf;
|
|
dev_t devt;
|
|
unsigned int nr_added_bufs;
|
|
int err;
|
|
|
|
port = kmalloc(sizeof(*port), GFP_KERNEL);
|
|
if (!port) {
|
|
err = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
kref_init(&port->kref);
|
|
|
|
port->portdev = portdev;
|
|
port->id = id;
|
|
|
|
port->name = NULL;
|
|
port->inbuf = NULL;
|
|
port->cons.hvc = NULL;
|
|
port->async_queue = NULL;
|
|
|
|
port->cons.ws.ws_row = port->cons.ws.ws_col = 0;
|
|
|
|
port->host_connected = port->guest_connected = false;
|
|
port->stats = (struct port_stats) { 0 };
|
|
|
|
port->outvq_full = false;
|
|
|
|
port->in_vq = portdev->in_vqs[port->id];
|
|
port->out_vq = portdev->out_vqs[port->id];
|
|
|
|
port->cdev = cdev_alloc();
|
|
if (!port->cdev) {
|
|
dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n");
|
|
err = -ENOMEM;
|
|
goto free_port;
|
|
}
|
|
port->cdev->ops = &port_fops;
|
|
|
|
devt = MKDEV(portdev->chr_major, id);
|
|
err = cdev_add(port->cdev, devt, 1);
|
|
if (err < 0) {
|
|
dev_err(&port->portdev->vdev->dev,
|
|
"Error %d adding cdev for port %u\n", err, id);
|
|
goto free_cdev;
|
|
}
|
|
port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
|
|
devt, port, "vport%up%u",
|
|
port->portdev->drv_index, id);
|
|
if (IS_ERR(port->dev)) {
|
|
err = PTR_ERR(port->dev);
|
|
dev_err(&port->portdev->vdev->dev,
|
|
"Error %d creating device for port %u\n",
|
|
err, id);
|
|
goto free_cdev;
|
|
}
|
|
|
|
spin_lock_init(&port->inbuf_lock);
|
|
spin_lock_init(&port->outvq_lock);
|
|
init_waitqueue_head(&port->waitqueue);
|
|
|
|
/* Fill the in_vq with buffers so the host can send us data. */
|
|
nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock);
|
|
if (!nr_added_bufs) {
|
|
dev_err(port->dev, "Error allocating inbufs\n");
|
|
err = -ENOMEM;
|
|
goto free_device;
|
|
}
|
|
|
|
/*
|
|
* If we're not using multiport support, this has to be a console port
|
|
*/
|
|
if (!use_multiport(port->portdev)) {
|
|
err = init_port_console(port);
|
|
if (err)
|
|
goto free_inbufs;
|
|
}
|
|
|
|
spin_lock_irq(&portdev->ports_lock);
|
|
list_add_tail(&port->list, &port->portdev->ports);
|
|
spin_unlock_irq(&portdev->ports_lock);
|
|
|
|
/*
|
|
* Tell the Host we're set so that it can send us various
|
|
* configuration parameters for this port (eg, port name,
|
|
* caching, whether this is a console port, etc.)
|
|
*/
|
|
send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
|
|
|
|
if (pdrvdata.debugfs_dir) {
|
|
/*
|
|
* Finally, create the debugfs file that we can use to
|
|
* inspect a port's state at any time
|
|
*/
|
|
sprintf(debugfs_name, "vport%up%u",
|
|
port->portdev->drv_index, id);
|
|
port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
|
|
pdrvdata.debugfs_dir,
|
|
port,
|
|
&port_debugfs_ops);
|
|
}
|
|
return 0;
|
|
|
|
free_inbufs:
|
|
while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
|
|
free_buf(buf);
|
|
free_device:
|
|
device_destroy(pdrvdata.class, port->dev->devt);
|
|
free_cdev:
|
|
cdev_del(port->cdev);
|
|
free_port:
|
|
kfree(port);
|
|
fail:
|
|
/* The host might want to notify management sw about port add failure */
|
|
__send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0);
|
|
return err;
|
|
}
|
|
|
|
/* No users remain, remove all port-specific data. */
|
|
static void remove_port(struct kref *kref)
|
|
{
|
|
struct port *port;
|
|
|
|
port = container_of(kref, struct port, kref);
|
|
|
|
sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
|
|
device_destroy(pdrvdata.class, port->dev->devt);
|
|
cdev_del(port->cdev);
|
|
|
|
kfree(port->name);
|
|
|
|
debugfs_remove(port->debugfs_file);
|
|
|
|
kfree(port);
|
|
}
|
|
|
|
static void remove_port_data(struct port *port)
|
|
{
|
|
struct port_buffer *buf;
|
|
|
|
/* Remove unused data this port might have received. */
|
|
discard_port_data(port);
|
|
|
|
reclaim_consumed_buffers(port);
|
|
|
|
/* Remove buffers we queued up for the Host to send us data in. */
|
|
while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
|
|
free_buf(buf);
|
|
}
|
|
|
|
/*
|
|
* Port got unplugged. Remove port from portdev's list and drop the
|
|
* kref reference. If no userspace has this port opened, it will
|
|
* result in immediate removal the port.
|
|
*/
|
|
static void unplug_port(struct port *port)
|
|
{
|
|
spin_lock_irq(&port->portdev->ports_lock);
|
|
list_del(&port->list);
|
|
spin_unlock_irq(&port->portdev->ports_lock);
|
|
|
|
if (port->guest_connected) {
|
|
port->guest_connected = false;
|
|
port->host_connected = false;
|
|
wake_up_interruptible(&port->waitqueue);
|
|
|
|
/* Let the app know the port is going down. */
|
|
send_sigio_to_port(port);
|
|
}
|
|
|
|
if (is_console_port(port)) {
|
|
spin_lock_irq(&pdrvdata_lock);
|
|
list_del(&port->cons.list);
|
|
spin_unlock_irq(&pdrvdata_lock);
|
|
hvc_remove(port->cons.hvc);
|
|
}
|
|
|
|
remove_port_data(port);
|
|
|
|
/*
|
|
* We should just assume the device itself has gone off --
|
|
* else a close on an open port later will try to send out a
|
|
* control message.
|
|
*/
|
|
port->portdev = NULL;
|
|
|
|
/*
|
|
* Locks around here are not necessary - a port can't be
|
|
* opened after we removed the port struct from ports_list
|
|
* above.
|
|
*/
|
|
kref_put(&port->kref, remove_port);
|
|
}
|
|
|
|
/* Any private messages that the Host and Guest want to share */
|
|
static void handle_control_message(struct ports_device *portdev,
|
|
struct port_buffer *buf)
|
|
{
|
|
struct virtio_console_control *cpkt;
|
|
struct port *port;
|
|
size_t name_size;
|
|
int err;
|
|
|
|
cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
|
|
|
|
port = find_port_by_id(portdev, cpkt->id);
|
|
if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) {
|
|
/* No valid header at start of buffer. Drop it. */
|
|
dev_dbg(&portdev->vdev->dev,
|
|
"Invalid index %u in control packet\n", cpkt->id);
|
|
return;
|
|
}
|
|
|
|
switch (cpkt->event) {
|
|
case VIRTIO_CONSOLE_PORT_ADD:
|
|
if (port) {
|
|
dev_dbg(&portdev->vdev->dev,
|
|
"Port %u already added\n", port->id);
|
|
send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
|
|
break;
|
|
}
|
|
if (cpkt->id >= portdev->config.max_nr_ports) {
|
|
dev_warn(&portdev->vdev->dev,
|
|
"Request for adding port with out-of-bound id %u, max. supported id: %u\n",
|
|
cpkt->id, portdev->config.max_nr_ports - 1);
|
|
break;
|
|
}
|
|
add_port(portdev, cpkt->id);
|
|
break;
|
|
case VIRTIO_CONSOLE_PORT_REMOVE:
|
|
unplug_port(port);
|
|
break;
|
|
case VIRTIO_CONSOLE_CONSOLE_PORT:
|
|
if (!cpkt->value)
|
|
break;
|
|
if (is_console_port(port))
|
|
break;
|
|
|
|
init_port_console(port);
|
|
complete(&early_console_added);
|
|
/*
|
|
* Could remove the port here in case init fails - but
|
|
* have to notify the host first.
|
|
*/
|
|
break;
|
|
case VIRTIO_CONSOLE_RESIZE: {
|
|
struct {
|
|
__u16 rows;
|
|
__u16 cols;
|
|
} size;
|
|
|
|
if (!is_console_port(port))
|
|
break;
|
|
|
|
memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt),
|
|
sizeof(size));
|
|
set_console_size(port, size.rows, size.cols);
|
|
|
|
port->cons.hvc->irq_requested = 1;
|
|
resize_console(port);
|
|
break;
|
|
}
|
|
case VIRTIO_CONSOLE_PORT_OPEN:
|
|
port->host_connected = cpkt->value;
|
|
wake_up_interruptible(&port->waitqueue);
|
|
/*
|
|
* If the host port got closed and the host had any
|
|
* unconsumed buffers, we'll be able to reclaim them
|
|
* now.
|
|
*/
|
|
spin_lock_irq(&port->outvq_lock);
|
|
reclaim_consumed_buffers(port);
|
|
spin_unlock_irq(&port->outvq_lock);
|
|
|
|
/*
|
|
* If the guest is connected, it'll be interested in
|
|
* knowing the host connection state changed.
|
|
*/
|
|
send_sigio_to_port(port);
|
|
break;
|
|
case VIRTIO_CONSOLE_PORT_NAME:
|
|
/*
|
|
* If we woke up after hibernation, we can get this
|
|
* again. Skip it in that case.
|
|
*/
|
|
if (port->name)
|
|
break;
|
|
|
|
/*
|
|
* Skip the size of the header and the cpkt to get the size
|
|
* of the name that was sent
|
|
*/
|
|
name_size = buf->len - buf->offset - sizeof(*cpkt) + 1;
|
|
|
|
port->name = kmalloc(name_size, GFP_KERNEL);
|
|
if (!port->name) {
|
|
dev_err(port->dev,
|
|
"Not enough space to store port name\n");
|
|
break;
|
|
}
|
|
strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt),
|
|
name_size - 1);
|
|
port->name[name_size - 1] = 0;
|
|
|
|
/*
|
|
* Since we only have one sysfs attribute, 'name',
|
|
* create it only if we have a name for the port.
|
|
*/
|
|
err = sysfs_create_group(&port->dev->kobj,
|
|
&port_attribute_group);
|
|
if (err) {
|
|
dev_err(port->dev,
|
|
"Error %d creating sysfs device attributes\n",
|
|
err);
|
|
} else {
|
|
/*
|
|
* Generate a udev event so that appropriate
|
|
* symlinks can be created based on udev
|
|
* rules.
|
|
*/
|
|
kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void control_work_handler(struct work_struct *work)
|
|
{
|
|
struct ports_device *portdev;
|
|
struct virtqueue *vq;
|
|
struct port_buffer *buf;
|
|
unsigned int len;
|
|
|
|
portdev = container_of(work, struct ports_device, control_work);
|
|
vq = portdev->c_ivq;
|
|
|
|
spin_lock(&portdev->cvq_lock);
|
|
while ((buf = virtqueue_get_buf(vq, &len))) {
|
|
spin_unlock(&portdev->cvq_lock);
|
|
|
|
buf->len = len;
|
|
buf->offset = 0;
|
|
|
|
handle_control_message(portdev, buf);
|
|
|
|
spin_lock(&portdev->cvq_lock);
|
|
if (add_inbuf(portdev->c_ivq, buf) < 0) {
|
|
dev_warn(&portdev->vdev->dev,
|
|
"Error adding buffer to queue\n");
|
|
free_buf(buf);
|
|
}
|
|
}
|
|
spin_unlock(&portdev->cvq_lock);
|
|
}
|
|
|
|
static void out_intr(struct virtqueue *vq)
|
|
{
|
|
struct port *port;
|
|
|
|
port = find_port_by_vq(vq->vdev->priv, vq);
|
|
if (!port)
|
|
return;
|
|
|
|
wake_up_interruptible(&port->waitqueue);
|
|
}
|
|
|
|
static void in_intr(struct virtqueue *vq)
|
|
{
|
|
struct port *port;
|
|
unsigned long flags;
|
|
|
|
port = find_port_by_vq(vq->vdev->priv, vq);
|
|
if (!port)
|
|
return;
|
|
|
|
spin_lock_irqsave(&port->inbuf_lock, flags);
|
|
port->inbuf = get_inbuf(port);
|
|
|
|
/*
|
|
* Don't queue up data when port is closed. This condition
|
|
* can be reached when a console port is not yet connected (no
|
|
* tty is spawned) and the host sends out data to console
|
|
* ports. For generic serial ports, the host won't
|
|
* (shouldn't) send data till the guest is connected.
|
|
*/
|
|
if (!port->guest_connected)
|
|
discard_port_data(port);
|
|
|
|
spin_unlock_irqrestore(&port->inbuf_lock, flags);
|
|
|
|
wake_up_interruptible(&port->waitqueue);
|
|
|
|
/* Send a SIGIO indicating new data in case the process asked for it */
|
|
send_sigio_to_port(port);
|
|
|
|
if (is_console_port(port) && hvc_poll(port->cons.hvc))
|
|
hvc_kick();
|
|
}
|
|
|
|
static void control_intr(struct virtqueue *vq)
|
|
{
|
|
struct ports_device *portdev;
|
|
|
|
portdev = vq->vdev->priv;
|
|
schedule_work(&portdev->control_work);
|
|
}
|
|
|
|
static void config_intr(struct virtio_device *vdev)
|
|
{
|
|
struct ports_device *portdev;
|
|
|
|
portdev = vdev->priv;
|
|
|
|
if (!use_multiport(portdev)) {
|
|
struct port *port;
|
|
u16 rows, cols;
|
|
|
|
vdev->config->get(vdev,
|
|
offsetof(struct virtio_console_config, cols),
|
|
&cols, sizeof(u16));
|
|
vdev->config->get(vdev,
|
|
offsetof(struct virtio_console_config, rows),
|
|
&rows, sizeof(u16));
|
|
|
|
port = find_port_by_id(portdev, 0);
|
|
set_console_size(port, rows, cols);
|
|
|
|
/*
|
|
* We'll use this way of resizing only for legacy
|
|
* support. For newer userspace
|
|
* (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
|
|
* to indicate console size changes so that it can be
|
|
* done per-port.
|
|
*/
|
|
resize_console(port);
|
|
}
|
|
}
|
|
|
|
static int init_vqs(struct ports_device *portdev)
|
|
{
|
|
vq_callback_t **io_callbacks;
|
|
char **io_names;
|
|
struct virtqueue **vqs;
|
|
u32 i, j, nr_ports, nr_queues;
|
|
int err;
|
|
|
|
nr_ports = portdev->config.max_nr_ports;
|
|
nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
|
|
|
|
vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
|
|
io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
|
|
io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
|
|
portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
|
|
GFP_KERNEL);
|
|
portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
|
|
GFP_KERNEL);
|
|
if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs ||
|
|
!portdev->out_vqs) {
|
|
err = -ENOMEM;
|
|
goto free;
|
|
}
|
|
|
|
/*
|
|
* For backward compat (newer host but older guest), the host
|
|
* spawns a console port first and also inits the vqs for port
|
|
* 0 before others.
|
|
*/
|
|
j = 0;
|
|
io_callbacks[j] = in_intr;
|
|
io_callbacks[j + 1] = out_intr;
|
|
io_names[j] = "input";
|
|
io_names[j + 1] = "output";
|
|
j += 2;
|
|
|
|
if (use_multiport(portdev)) {
|
|
io_callbacks[j] = control_intr;
|
|
io_callbacks[j + 1] = NULL;
|
|
io_names[j] = "control-i";
|
|
io_names[j + 1] = "control-o";
|
|
|
|
for (i = 1; i < nr_ports; i++) {
|
|
j += 2;
|
|
io_callbacks[j] = in_intr;
|
|
io_callbacks[j + 1] = out_intr;
|
|
io_names[j] = "input";
|
|
io_names[j + 1] = "output";
|
|
}
|
|
}
|
|
/* Find the queues. */
|
|
err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
|
|
io_callbacks,
|
|
(const char **)io_names);
|
|
if (err)
|
|
goto free;
|
|
|
|
j = 0;
|
|
portdev->in_vqs[0] = vqs[0];
|
|
portdev->out_vqs[0] = vqs[1];
|
|
j += 2;
|
|
if (use_multiport(portdev)) {
|
|
portdev->c_ivq = vqs[j];
|
|
portdev->c_ovq = vqs[j + 1];
|
|
|
|
for (i = 1; i < nr_ports; i++) {
|
|
j += 2;
|
|
portdev->in_vqs[i] = vqs[j];
|
|
portdev->out_vqs[i] = vqs[j + 1];
|
|
}
|
|
}
|
|
kfree(io_names);
|
|
kfree(io_callbacks);
|
|
kfree(vqs);
|
|
|
|
return 0;
|
|
|
|
free:
|
|
kfree(portdev->out_vqs);
|
|
kfree(portdev->in_vqs);
|
|
kfree(io_names);
|
|
kfree(io_callbacks);
|
|
kfree(vqs);
|
|
|
|
return err;
|
|
}
|
|
|
|
static const struct file_operations portdev_fops = {
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static void remove_vqs(struct ports_device *portdev)
|
|
{
|
|
portdev->vdev->config->del_vqs(portdev->vdev);
|
|
kfree(portdev->in_vqs);
|
|
kfree(portdev->out_vqs);
|
|
}
|
|
|
|
static void remove_controlq_data(struct ports_device *portdev)
|
|
{
|
|
struct port_buffer *buf;
|
|
unsigned int len;
|
|
|
|
if (!use_multiport(portdev))
|
|
return;
|
|
|
|
while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
|
|
free_buf(buf);
|
|
|
|
while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
|
|
free_buf(buf);
|
|
}
|
|
|
|
/*
|
|
* Once we're further in boot, we get probed like any other virtio
|
|
* device.
|
|
*
|
|
* If the host also supports multiple console ports, we check the
|
|
* config space to see how many ports the host has spawned. We
|
|
* initialize each port found.
|
|
*/
|
|
static int __devinit virtcons_probe(struct virtio_device *vdev)
|
|
{
|
|
struct ports_device *portdev;
|
|
int err;
|
|
bool multiport;
|
|
bool early = early_put_chars != NULL;
|
|
|
|
/* Ensure to read early_put_chars now */
|
|
barrier();
|
|
|
|
portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
|
|
if (!portdev) {
|
|
err = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
|
|
/* Attach this portdev to this virtio_device, and vice-versa. */
|
|
portdev->vdev = vdev;
|
|
vdev->priv = portdev;
|
|
|
|
spin_lock_irq(&pdrvdata_lock);
|
|
portdev->drv_index = pdrvdata.index++;
|
|
spin_unlock_irq(&pdrvdata_lock);
|
|
|
|
portdev->chr_major = register_chrdev(0, "virtio-portsdev",
|
|
&portdev_fops);
|
|
if (portdev->chr_major < 0) {
|
|
dev_err(&vdev->dev,
|
|
"Error %d registering chrdev for device %u\n",
|
|
portdev->chr_major, portdev->drv_index);
|
|
err = portdev->chr_major;
|
|
goto free;
|
|
}
|
|
|
|
multiport = false;
|
|
portdev->config.max_nr_ports = 1;
|
|
if (virtio_config_val(vdev, VIRTIO_CONSOLE_F_MULTIPORT,
|
|
offsetof(struct virtio_console_config,
|
|
max_nr_ports),
|
|
&portdev->config.max_nr_ports) == 0)
|
|
multiport = true;
|
|
|
|
err = init_vqs(portdev);
|
|
if (err < 0) {
|
|
dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
|
|
goto free_chrdev;
|
|
}
|
|
|
|
spin_lock_init(&portdev->ports_lock);
|
|
INIT_LIST_HEAD(&portdev->ports);
|
|
|
|
if (multiport) {
|
|
unsigned int nr_added_bufs;
|
|
|
|
spin_lock_init(&portdev->cvq_lock);
|
|
INIT_WORK(&portdev->control_work, &control_work_handler);
|
|
|
|
nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
|
|
if (!nr_added_bufs) {
|
|
dev_err(&vdev->dev,
|
|
"Error allocating buffers for control queue\n");
|
|
err = -ENOMEM;
|
|
goto free_vqs;
|
|
}
|
|
} else {
|
|
/*
|
|
* For backward compatibility: Create a console port
|
|
* if we're running on older host.
|
|
*/
|
|
add_port(portdev, 0);
|
|
}
|
|
|
|
spin_lock_irq(&pdrvdata_lock);
|
|
list_add_tail(&portdev->list, &pdrvdata.portdevs);
|
|
spin_unlock_irq(&pdrvdata_lock);
|
|
|
|
__send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
|
|
VIRTIO_CONSOLE_DEVICE_READY, 1);
|
|
|
|
/*
|
|
* If there was an early virtio console, assume that there are no
|
|
* other consoles. We need to wait until the hvc_alloc matches the
|
|
* hvc_instantiate, otherwise tty_open will complain, resulting in
|
|
* a "Warning: unable to open an initial console" boot failure.
|
|
* Without multiport this is done in add_port above. With multiport
|
|
* this might take some host<->guest communication - thus we have to
|
|
* wait.
|
|
*/
|
|
if (multiport && early)
|
|
wait_for_completion(&early_console_added);
|
|
|
|
return 0;
|
|
|
|
free_vqs:
|
|
/* The host might want to notify mgmt sw about device add failure */
|
|
__send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
|
|
VIRTIO_CONSOLE_DEVICE_READY, 0);
|
|
remove_vqs(portdev);
|
|
free_chrdev:
|
|
unregister_chrdev(portdev->chr_major, "virtio-portsdev");
|
|
free:
|
|
kfree(portdev);
|
|
fail:
|
|
return err;
|
|
}
|
|
|
|
static void virtcons_remove(struct virtio_device *vdev)
|
|
{
|
|
struct ports_device *portdev;
|
|
struct port *port, *port2;
|
|
|
|
portdev = vdev->priv;
|
|
|
|
spin_lock_irq(&pdrvdata_lock);
|
|
list_del(&portdev->list);
|
|
spin_unlock_irq(&pdrvdata_lock);
|
|
|
|
/* Disable interrupts for vqs */
|
|
vdev->config->reset(vdev);
|
|
/* Finish up work that's lined up */
|
|
cancel_work_sync(&portdev->control_work);
|
|
|
|
list_for_each_entry_safe(port, port2, &portdev->ports, list)
|
|
unplug_port(port);
|
|
|
|
unregister_chrdev(portdev->chr_major, "virtio-portsdev");
|
|
|
|
/*
|
|
* When yanking out a device, we immediately lose the
|
|
* (device-side) queues. So there's no point in keeping the
|
|
* guest side around till we drop our final reference. This
|
|
* also means that any ports which are in an open state will
|
|
* have to just stop using the port, as the vqs are going
|
|
* away.
|
|
*/
|
|
remove_controlq_data(portdev);
|
|
remove_vqs(portdev);
|
|
kfree(portdev);
|
|
}
|
|
|
|
static struct virtio_device_id id_table[] = {
|
|
{ VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID },
|
|
{ 0 },
|
|
};
|
|
|
|
static unsigned int features[] = {
|
|
VIRTIO_CONSOLE_F_SIZE,
|
|
VIRTIO_CONSOLE_F_MULTIPORT,
|
|
};
|
|
|
|
#ifdef CONFIG_PM
|
|
static int virtcons_freeze(struct virtio_device *vdev)
|
|
{
|
|
struct ports_device *portdev;
|
|
struct port *port;
|
|
|
|
portdev = vdev->priv;
|
|
|
|
vdev->config->reset(vdev);
|
|
|
|
virtqueue_disable_cb(portdev->c_ivq);
|
|
cancel_work_sync(&portdev->control_work);
|
|
/*
|
|
* Once more: if control_work_handler() was running, it would
|
|
* enable the cb as the last step.
|
|
*/
|
|
virtqueue_disable_cb(portdev->c_ivq);
|
|
remove_controlq_data(portdev);
|
|
|
|
list_for_each_entry(port, &portdev->ports, list) {
|
|
virtqueue_disable_cb(port->in_vq);
|
|
virtqueue_disable_cb(port->out_vq);
|
|
/*
|
|
* We'll ask the host later if the new invocation has
|
|
* the port opened or closed.
|
|
*/
|
|
port->host_connected = false;
|
|
remove_port_data(port);
|
|
}
|
|
remove_vqs(portdev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int virtcons_restore(struct virtio_device *vdev)
|
|
{
|
|
struct ports_device *portdev;
|
|
struct port *port;
|
|
int ret;
|
|
|
|
portdev = vdev->priv;
|
|
|
|
ret = init_vqs(portdev);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (use_multiport(portdev))
|
|
fill_queue(portdev->c_ivq, &portdev->cvq_lock);
|
|
|
|
list_for_each_entry(port, &portdev->ports, list) {
|
|
port->in_vq = portdev->in_vqs[port->id];
|
|
port->out_vq = portdev->out_vqs[port->id];
|
|
|
|
fill_queue(port->in_vq, &port->inbuf_lock);
|
|
|
|
/* Get port open/close status on the host */
|
|
send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
|
|
|
|
/*
|
|
* If a port was open at the time of suspending, we
|
|
* have to let the host know that it's still open.
|
|
*/
|
|
if (port->guest_connected)
|
|
send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static struct virtio_driver virtio_console = {
|
|
.feature_table = features,
|
|
.feature_table_size = ARRAY_SIZE(features),
|
|
.driver.name = KBUILD_MODNAME,
|
|
.driver.owner = THIS_MODULE,
|
|
.id_table = id_table,
|
|
.probe = virtcons_probe,
|
|
.remove = virtcons_remove,
|
|
.config_changed = config_intr,
|
|
#ifdef CONFIG_PM
|
|
.freeze = virtcons_freeze,
|
|
.restore = virtcons_restore,
|
|
#endif
|
|
};
|
|
|
|
static int __init init(void)
|
|
{
|
|
int err;
|
|
|
|
pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
|
|
if (IS_ERR(pdrvdata.class)) {
|
|
err = PTR_ERR(pdrvdata.class);
|
|
pr_err("Error %d creating virtio-ports class\n", err);
|
|
return err;
|
|
}
|
|
|
|
pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
|
|
if (!pdrvdata.debugfs_dir) {
|
|
pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
|
|
PTR_ERR(pdrvdata.debugfs_dir));
|
|
}
|
|
INIT_LIST_HEAD(&pdrvdata.consoles);
|
|
INIT_LIST_HEAD(&pdrvdata.portdevs);
|
|
|
|
err = register_virtio_driver(&virtio_console);
|
|
if (err < 0) {
|
|
pr_err("Error %d registering virtio driver\n", err);
|
|
goto free;
|
|
}
|
|
return 0;
|
|
free:
|
|
if (pdrvdata.debugfs_dir)
|
|
debugfs_remove_recursive(pdrvdata.debugfs_dir);
|
|
class_destroy(pdrvdata.class);
|
|
return err;
|
|
}
|
|
|
|
static void __exit fini(void)
|
|
{
|
|
unregister_virtio_driver(&virtio_console);
|
|
|
|
class_destroy(pdrvdata.class);
|
|
if (pdrvdata.debugfs_dir)
|
|
debugfs_remove_recursive(pdrvdata.debugfs_dir);
|
|
}
|
|
module_init(init);
|
|
module_exit(fini);
|
|
|
|
MODULE_DEVICE_TABLE(virtio, id_table);
|
|
MODULE_DESCRIPTION("Virtio console driver");
|
|
MODULE_LICENSE("GPL");
|