// SPDX-License-Identifier: GPL-2.0-or-later
/*
* xen-hcd.c
*
* Xen USB Virtual Host Controller driver
*
* Copyright (C) 2009, FUJITSU LABORATORIES LTD.
* Author: Noboru Iwamatsu <[email protected]>
*/
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/list.h>
#include <linux/usb/hcd.h>
#include <linux/io.h>
#include <xen/xen.h>
#include <xen/xenbus.h>
#include <xen/grant_table.h>
#include <xen/events.h>
#include <xen/page.h>
#include <xen/interface/io/usbif.h>
/* Private per-URB data */
struct urb_priv {
struct list_head list;
struct urb *urb;
int req_id; /* RING_REQUEST id for submitting */
int unlink_req_id; /* RING_REQUEST id for unlinking */
int status;
bool unlinked; /* dequeued marker */
};
/* virtual roothub port status */
struct rhport_status {
__u32 status;
bool resuming; /* in resuming */
bool c_connection; /* connection changed */
unsigned long timeout;
};
/* status of attached device */
struct vdevice_status {
int devnum;
enum usb_device_state status;
enum usb_device_speed speed;
};
/* RING request shadow */
struct usb_shadow {
struct xenusb_urb_request req;
struct urb *urb;
bool in_flight;
};
struct xenhcd_info {
/* Virtual Host Controller has 4 urb queues */
struct list_head pending_submit_list;
struct list_head pending_unlink_list;
struct list_head in_progress_list;
struct list_head giveback_waiting_list;
spinlock_t lock;
/* timer that kick pending and giveback waiting urbs */
struct timer_list watchdog;
unsigned long actions;
/* virtual root hub */
int rh_numports;
struct rhport_status ports[XENUSB_MAX_PORTNR];
struct vdevice_status devices[XENUSB_MAX_PORTNR];
/* Xen related staff */
struct xenbus_device *xbdev;
int urb_ring_ref;
int conn_ring_ref;
struct xenusb_urb_front_ring urb_ring;
struct xenusb_conn_front_ring conn_ring;
unsigned int evtchn;
unsigned int irq;
struct usb_shadow shadow[XENUSB_URB_RING_SIZE];
unsigned int shadow_free;
bool error;
};
#define XENHCD_RING_JIFFIES (HZ/200)
#define XENHCD_SCAN_JIFFIES 1
enum xenhcd_timer_action {
TIMER_RING_WATCHDOG,
TIMER_SCAN_PENDING_URBS,
};
static struct kmem_cache *xenhcd_urbp_cachep;
static inline struct xenhcd_info *xenhcd_hcd_to_info(struct usb_hcd *hcd)
{
return (struct xenhcd_info *)hcd->hcd_priv;
}
static inline struct usb_hcd *xenhcd_info_to_hcd(struct xenhcd_info *info)
{
return container_of((void *)info, struct usb_hcd, hcd_priv);
}
static void xenhcd_set_error(struct xenhcd_info *info, const char *msg)
{
info->error = true;
pr_alert("xen-hcd: protocol error: %s!\n", msg);
}
static inline void xenhcd_timer_action_done(struct xenhcd_info *info,
enum xenhcd_timer_action action)
{
clear_bit(action, &info->actions);
}
static void xenhcd_timer_action(struct xenhcd_info *info,
enum xenhcd_timer_action action)
{
if (timer_pending(&info->watchdog) &&
test_bit(TIMER_SCAN_PENDING_URBS, &info->actions))
return;
if (!test_and_set_bit(action, &info->actions)) {
unsigned long t;
switch (action) {
case TIMER_RING_WATCHDOG:
t = XENHCD_RING_JIFFIES;
break;
default:
t = XENHCD_SCAN_JIFFIES;
break;
}
mod_timer(&info->watchdog, t + jiffies);
}
}
/*
* set virtual port connection status
*/
static void xenhcd_set_connect_state(struct xenhcd_info *info, int portnum)
{
int port;
port = portnum - 1;
if (info->ports[port].status & USB_PORT_STAT_POWER) {
switch (info->devices[port].speed) {
case XENUSB_SPEED_NONE:
info->ports[port].status &=
~(USB_PORT_STAT_CONNECTION |
USB_PORT_STAT_ENABLE |
USB_PORT_STAT_LOW_SPEED |
USB_PORT_STAT_HIGH_SPEED |
USB_PORT_STAT_SUSPEND);
break;
case XENUSB_SPEED_LOW:
info->ports[port].status |= USB_PORT_STAT_CONNECTION;
info->ports[port].status |= USB_PORT_STAT_LOW_SPEED;
break;
case XENUSB_SPEED_FULL:
info->ports[port].status |= USB_PORT_STAT_CONNECTION;
break;
case XENUSB_SPEED_HIGH:
info->ports[port].status |= USB_PORT_STAT_CONNECTION;
info->ports[port].status |= USB_PORT_STAT_HIGH_SPEED;
break;
default: /* error */
return;
}
info->ports[port].status |= (USB_PORT_STAT_C_CONNECTION << 16);
}
}
/*
* set virtual device connection status
*/
static int xenhcd_rhport_connect(struct xenhcd_info *info, __u8 portnum,
__u8 speed)
{
int port;
if (portnum < 1 || portnum > info->rh_numports)
return -EINVAL; /* invalid port number */
port = portnum - 1;
if (info->devices[port].speed != speed) {
switch (speed) {
case XENUSB_SPEED_NONE: /* disconnect */
info->devices[port].status = USB_STATE_NOTATTACHED;
break;
case XENUSB_SPEED_LOW:
case XENUSB_SPEED_FULL:
case XENUSB_SPEED_HIGH:
info->devices[port].status = USB_STATE_ATTACHED;
break;
default: /* error */
return -EINVAL;
}
info->devices[port].speed = speed;
info->ports[port].c_connection = true;
xenhcd_set_connect_state(info, portnum);
}
return 0;
}
/*
* SetPortFeature(PORT_SUSPENDED)
*/
static void xenhcd_rhport_suspend(struct xenhcd_info *info, int portnum)
{
int port;
port = portnum - 1;
info->ports[port].status |= USB_PORT_STAT_SUSPEND;
info->devices[port].status = USB_STATE_SUSPENDED;
}
/*
* ClearPortFeature(PORT_SUSPENDED)
*/
static void xenhcd_rhport_resume(struct xenhcd_info *info, int portnum)
{
int port;
port = portnum - 1;
if (info->ports[port].status & USB_PORT_STAT_SUSPEND) {
info->ports[port].resuming = true;
info->ports[port].timeout = jiffies + msecs_to_jiffies(20);
}
}
/*
* SetPortFeature(PORT_POWER)
*/
static void xenhcd_rhport_power_on(struct xenhcd_info *info, int portnum)
{
int port;
port = portnum - 1;
if ((info->ports[port].status & USB_PORT_STAT_POWER) == 0) {
info->ports[port].status |= USB_PORT_STAT_POWER;
if (info->devices[port].status != USB_STATE_NOTATTACHED)
info->devices[port].status = USB_STATE_POWERED;
if (info->ports[port].c_connection)
xenhcd_set_connect_state(info, portnum);
}
}
/*
* ClearPortFeature(PORT_POWER)
* SetConfiguration(non-zero)
* Power_Source_Off
* Over-current
*/
static void xenhcd_rhport_power_off(struct xenhcd_info *info, int portnum)
{
int port;
port = portnum - 1;
if (info->ports[port].status & USB_PORT_STAT_POWER) {
info->ports[port].status = 0;
if (info->devices[port].status != USB_STATE_NOTATTACHED)
info->devices[port].status = USB_STATE_ATTACHED;
}
}
/*
* ClearPortFeature(PORT_ENABLE)
*/
static void xenhcd_rhport_disable(struct xenhcd_info *info, int portnum)
{
int port;
port = portnum - 1;
info->ports[port].status &= ~USB_PORT_STAT_ENABLE;
info->ports[port].status &= ~USB_PORT_STAT_SUSPEND;
info->ports[port].resuming = false;
if (info->devices[port].status != USB_STATE_NOTATTACHED)
info->devices[port].status = USB_STATE_POWERED;
}
/*
* SetPortFeature(PORT_RESET)
*/
static void xenhcd_rhport_reset(struct xenhcd_info *info, int portnum)
{
int port;
port = portnum - 1;
info->ports[port].status &= ~(USB_PORT_STAT_ENABLE |
USB_PORT_STAT_LOW_SPEED |
USB_PORT_STAT_HIGH_SPEED);
info->ports[port].status |= USB_PORT_STAT_RESET;
if (info->devices[port].status != USB_STATE_NOTATTACHED)
info->devices[port].status = USB_STATE_ATTACHED;
/* 10msec reset signaling */
info->ports[port].timeout = jiffies + msecs_to_jiffies(10);
}
#ifdef CONFIG_PM
static int xenhcd_bus_suspend(struct usb_hcd *hcd)
{
struct xenhcd_info *info = xenhcd_hcd_to_info(hcd);
int ret = 0;
int i, ports;
ports = info->rh_numports;
spin_lock_irq(&info->lock);
if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
ret = -ESHUTDOWN;
} else {
/* suspend any active ports*/
for (i = 1; i <= ports; i++)
xenhcd_rhport_suspend(info, i);
}
spin_unlock_irq(&info->lock);
del_timer_sync(&info->watchdog);
return ret;
}
static int xenhcd_bus_resume(struct usb_hcd *hcd)
{
struct xenhcd_info *info = xenhcd_hcd_to_info(hcd);
int ret = 0;
int i, ports;
ports = info->rh_numports;
spin_lock_irq(&info->lock);
if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
ret = -ESHUTDOWN;
} else {
/* resume any suspended ports*/
for (i = 1; i <= ports; i++)
xenhcd_rhport_resume(info, i);
}
spin_unlock_irq(&info->lock);
return ret;
}
#endif
static void xenhcd_hub_descriptor(struct xenhcd_info *info,
struct usb_hub_descriptor *desc)
{
__u16 temp;
int ports = info->rh_numports;
desc->bDescriptorType = 0x29;
desc->bPwrOn2PwrGood = 10; /* EHCI says 20ms max */
desc->bHubContrCurrent = 0;
desc->bNbrPorts = ports;
/* size of DeviceRemovable and PortPwrCtrlMask fields */
temp = 1 + (ports / 8);
desc->bDescLength = 7 + 2 * temp;
/* bitmaps for DeviceRemovable and PortPwrCtrlMask */
memset(&desc->u.hs.DeviceRemovable[0], 0, temp);
memset(&desc->u.hs.DeviceRemovable[temp], 0xff, temp);
/* per-port over current reporting and no power switching */
temp = 0x000a;
desc->wHubCharacteristics = cpu_to_le16(temp);
}
/* port status change mask for hub_status_data */
#define PORT_C_MASK ((USB_PORT_STAT_C_CONNECTION | \
USB_PORT_STAT_C_ENABLE | \
USB_PORT_STAT_C_SUSPEND | \
USB_PORT_STAT_C_OVERCURRENT | \
USB_PORT_STAT_C_RESET) << 16)
/*
* See USB 2.0 Spec, 11.12.4 Hub and Port Status Change Bitmap.
* If port status changed, writes the bitmap to buf and return
* that length(number of bytes).
* If Nothing changed, return 0.
*/
static int xenhcd_hub_status_data(struct usb_hcd *hcd, char *buf)
{
struct xenhcd_info *info = xenhcd_hcd_to_info(hcd);
int ports;
int i;
unsigned long flags;
int ret;
int changed = 0;
/* initialize the status to no-changes */
ports = info->rh_numports;
ret = 1 + (ports / 8);
memset(buf, 0, ret);
spin_lock_irqsave(&info->lock, flags);
for (i = 0; i < ports; i++) {
/* check status for each port */
if (info->ports[i].status & PORT_C_MASK) {
buf[(i + 1) / 8] |= 1 << (i + 1) % 8;
changed = 1;
}
}
if ((hcd->state == HC_STATE_SUSPENDED) && (changed == 1))
usb_hcd_resume_root_hub(hcd);
spin_unlock_irqrestore(&info->lock, flags);
return changed ? ret : 0;
}
static int xenhcd_hub_control(struct usb_hcd *hcd, __u16 typeReq, __u16 wValue,
__u16 wIndex, char *buf, __u16 wLength)
{
struct xenhcd_info *info = xenhcd_hcd_to_info(hcd);
int ports = info->rh_numports;
unsigned long flags;
int ret = 0;
int i;
int changed = 0;
spin_lock_irqsave(&info->lock, flags);
switch (typeReq) {
case ClearHubFeature:
/* ignore this request */
break;
case ClearPortFeature:
if (!wIndex || wIndex > ports)
goto error;
switch (wValue) {
case USB_PORT_FEAT_SUSPEND:
xenhcd_rhport_resume(info, wIndex);
break;
case USB_PORT_FEAT_POWER:
xenhcd_rhport_power_off(info, wIndex);
break;
case USB_PORT_FEAT_ENABLE:
xenhcd_rhport_disable(info, wIndex);
break;
case USB_PORT_FEAT_C_CONNECTION:
info->ports[wIndex - 1].c_connection = false;
fallthrough;
default:
info->ports[wIndex - 1].status &= ~(1 << wValue);
break;
}
break;
case GetHubDescriptor:
xenhcd_hub_descriptor(info, (struct usb_hub_descriptor *)buf);
break;
case GetHubStatus:
/* always local power supply good and no over-current exists. */
*(__le32 *)buf = cpu_to_le32(0);
break;
case GetPortStatus:
if (!wIndex || wIndex > ports)
goto error;
wIndex--;
/* resume completion */
if (info->ports[wIndex].resuming &&
time_after_eq(jiffies, info->ports[wIndex].timeout)) {
info->ports[wIndex].status |=
USB_PORT_STAT_C_SUSPEND << 16;
info->ports[wIndex].status &= ~USB_PORT_STAT_SUSPEND;
}
/* reset completion */
if ((info->ports[wIndex].status & USB_PORT_STAT_RESET) != 0 &&
time_after_eq(jiffies, info->ports[wIndex].timeout)) {
info->ports[wIndex].status |=
USB_PORT_STAT_C_RESET << 16;
info->ports[wIndex].status &= ~USB_PORT_STAT_RESET;
if (info->devices[wIndex].status !=
USB_STATE_NOTATTACHED) {
info->ports[wIndex].status |=
USB_PORT_STAT_ENABLE;
info->devices[wIndex].status =
USB_STATE_DEFAULT;
}
switch (info->devices[wIndex].speed) {
case XENUSB_SPEED_LOW:
info->ports[wIndex].status |=
USB_PORT_STAT_LOW_SPEED;
break;
case XENUSB_SPEED_HIGH:
info->ports[wIndex].status |=
USB_PORT_STAT_HIGH_SPEED;
break;
default:
break;
}
}
*(__le32 *)buf = cpu_to_le32(info->ports[wIndex].status);
break;
case SetPortFeature:
if (!wIndex || wIndex > ports)
goto error;
switch (wValue) {
case USB_PORT_FEAT_POWER:
xenhcd_rhport_power_on(info, wIndex);
break;
case USB_PORT_FEAT_RESET:
xenhcd_rhport_reset(info, wIndex);
break;
case USB_PORT_FEAT_SUSPEND:
xenhcd_rhport_suspend(info, wIndex);
break;
default:
if (info->ports[wIndex-1].status & USB_PORT_STAT_POWER)
info->ports[wIndex-1].status |= (1 << wValue);
}
break;
case SetHubFeature:
/* not supported */
default:
error:
ret = -EPIPE;
}
spin_unlock_irqrestore(&info->lock, flags);
/* check status for each port */
for (i = 0; i < ports; i++) {
if (info->ports[i].status & PORT_C_MASK)
changed = 1;
}
if (changed)
usb_hcd_poll_rh_status(hcd);
return ret;
}
static void xenhcd_free_urb_priv(struct urb_priv *urbp)
{
urbp->urb->hcpriv = NULL;
kmem_cache_free(xenhcd_urbp_cachep, urbp);
}
static inline unsigned int xenhcd_get_id_from_freelist(struct xenhcd_info *info)
{
unsigned int free;
free = info->shadow_free;
info->shadow_free = info->shadow[free].req.id;
info->shadow[free].req.id = 0x0fff; /* debug */
return free;
}
static inline void xenhcd_add_id_to_freelist(struct xenhcd_info *info,
unsigned int id)
{
info->shadow[id].req.id = info->shadow_free;
info->shadow[id].urb = NULL;
info->shadow_free = id;
}
static inline int xenhcd_count_pages(void *addr, int length)
{
unsigned long vaddr = (unsigned long)addr;
return PFN_UP(vaddr + length) - PFN_DOWN(vaddr);
}
static void xenhcd_gnttab_map(struct xenhcd_info *info, void *addr, int length,
grant_ref_t *gref_head,
struct xenusb_request_segment *seg,
int nr_pages, int flags)
{
grant_ref_t ref;
unsigned int offset;
unsigned int len = length;
unsigned int bytes;
int i;
for (i = 0; i < nr_pages; i++) {
offset = offset_in_page(addr);
bytes = PAGE_SIZE - offset;
if (bytes > len)
bytes = len;
ref = gnttab_claim_grant_reference(gref_head);
gnttab_grant_foreign_access_ref(ref, info->xbdev->otherend_id,
virt_to_gfn(addr), flags);
seg[i].gref = ref;
seg[i].offset = (__u16)offset;
seg[i].length = (__u16)bytes;
addr += bytes;
len -= bytes;
}
}
static __u32 xenhcd_pipe_urb_to_xenusb(__u32 urb_pipe, __u8 port)
{
static __u32 pipe;
pipe = usb_pipedevice(urb_pipe) << XENUSB_PIPE_DEV_SHIFT;
pipe |= usb_pipeendpoint(urb_pipe) << XENUSB_PIPE_EP_SHIFT;
if (usb_pipein(urb_pipe))
pipe |= XENUSB_PIPE_DIR;
switch (usb_pipetype(urb_pipe)) {
case PIPE_ISOCHRONOUS:
pipe |= XENUSB_PIPE_TYPE_ISOC << XENUSB_PIPE_TYPE_SHIFT;
break;
case PIPE_INTERRUPT:
pipe |= XENUSB_PIPE_TYPE_INT << XENUSB_PIPE_TYPE_SHIFT;
break;
case PIPE_CONTROL:
pipe |= XENUSB_PIPE_TYPE_CTRL << XENUSB_PIPE_TYPE_SHIFT;
break;
case PIPE_BULK:
pipe |= XENUSB_PIPE_TYPE_BULK << XENUSB_PIPE_TYPE_SHIFT;
break;
}
pipe = xenusb_setportnum_pipe(pipe, port);
return pipe;
}
static int xenhcd_map_urb_for_request(struct xenhcd_info *info, struct urb *urb,
struct xenusb_urb_request *req)
{
grant_ref_t gref_head;
int nr_buff_pages = 0;
int nr_isodesc_pages = 0;
int nr_grants = 0;
if (urb->transfer_buffer_length) {
nr_buff_pages = xenhcd_count_pages(urb->transfer_buffer,
urb->transfer_buffer_length);
if (usb_pipeisoc(urb->pipe))
nr_isodesc_pages = xenhcd_count_pages(
&urb->iso_frame_desc[0],
sizeof(struct usb_iso_packet_descriptor) *
urb->number_of_packets);
nr_grants = nr_buff_pages + nr_isodesc_pages;
if (nr_grants > XENUSB_MAX_SEGMENTS_PER_REQUEST) {
pr_err("xenhcd: error: %d grants\n", nr_grants);
return -E2BIG;
}
if (gnttab_alloc_grant_references(nr_grants, &gref_head)) {
pr_err("xenhcd: gnttab_alloc_grant_references() error\n");
return -ENOMEM;
}
xenhcd_gnttab_map(info, urb->transfer_buffer,
urb->transfer_buffer_length, &gref_head,
&req->seg[0], nr_buff_pages,
usb_pipein(urb->pipe) ? 0 : GTF_readonly);
}
req->pipe = xenhcd_pipe_urb_to_xenusb(urb->pipe, urb->dev->portnum);
req->transfer_flags = 0;
if (urb->transfer_flags & URB_SHORT_NOT_OK)
req->transfer_flags |= XENUSB_SHORT_NOT_OK;
req->buffer_length = urb->transfer_buffer_length;
req->nr_buffer_segs = nr_buff_pages;
switch (usb_pipetype(urb->pipe)) {
case PIPE_ISOCHRONOUS:
req->u.isoc.interval = urb->interval;
req->u.isoc.start_frame = urb->start_frame;
req->u.isoc.number_of_packets = urb->number_of_packets;
req->u.isoc.nr_frame_desc_segs = nr_isodesc_pages;
xenhcd_gnttab_map(info, &urb->iso_frame_desc[0],
sizeof(struct usb_iso_packet_descriptor) *
urb->number_of_packets,
&gref_head, &req->seg[nr_buff_pages],
nr_isodesc_pages, 0);
break;
case PIPE_INTERRUPT:
req->u.intr.interval = urb->interval;
break;
case PIPE_CONTROL:
if (urb->setup_packet)
memcpy(req->u.ctrl, urb->setup_packet, 8);
break;
case PIPE_BULK:
break;
default:
break;
}
if (nr_grants)
gnttab_free_grant_references(gref_head);
return 0;
}
static void xenhcd_gnttab_done(struct xenhcd_info *info, unsigned int id)
{
struct usb_shadow *shadow = info->shadow + id;
int nr_segs = 0;
int i;
if (!shadow->in_flight) {
xenhcd_set_error(info, "Illegal request id");
return;
}
shadow->in_flight = false;
nr_segs = shadow->req.nr_buffer_segs;
if (xenusb_pipeisoc(shadow->req.pipe))
nr_segs += shadow->req.u.isoc.nr_frame_desc_segs;
for (i = 0; i < nr_segs; i++) {
if (!gnttab_try_end_foreign_access(shadow->req.seg[i].gref))
xenhcd_set_error(info, "backend didn't release grant");
}
shadow->req.nr_buffer_segs = 0;
shadow->req.u.isoc.nr_frame_desc_segs = 0;
}
static int xenhcd_translate_status(int status)
{
switch (status) {
case XENUSB_STATUS_OK:
return 0;
case XENUSB_STATUS_NODEV:
return -ENODEV;
case XENUSB_STATUS_INVAL:
return -EINVAL;
case XENUSB_STATUS_STALL:
return -EPIPE;
case XENUSB_STATUS_IOERROR:
return -EPROTO;
case XENUSB_STATUS_BABBLE:
return -EOVERFLOW;
default:
return -ESHUTDOWN;
}
}
static void xenhcd_giveback_urb(struct xenhcd_info *info, struct urb *urb,
int status)
{
struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
int priv_status = urbp->status;
list_del_init(&urbp->list);
xenhcd_free_urb_priv(urbp);
if (urb->status == -EINPROGRESS)
urb->status = xenhcd_translate_status(status);
spin_unlock(&info->lock);
usb_hcd_giveback_urb(xenhcd_info_to_hcd(info), urb,
priv_status <= 0 ? priv_status : urb->status);
spin_lock(&info->lock);
}
static int xenhcd_do_request(struct xenhcd_info *info, struct urb_priv *urbp)
{
struct xenusb_urb_request *req;
struct urb *urb = urbp->urb;
unsigned int id;
int notify;
int ret;
id = xenhcd_get_id_from_freelist(info);
req = &info->shadow[id].req;
req->id = id;
if (unlikely(urbp->unlinked)) {
req->u.unlink.unlink_id = urbp->req_id;
req->pipe = xenusb_setunlink_pipe(xenhcd_pipe_urb_to_xenusb(
urb->pipe, urb->dev->portnum));
urbp->unlink_req_id = id;
} else {
ret = xenhcd_map_urb_for_request(info, urb, req);
if (ret) {
xenhcd_add_id_to_freelist(info, id);
return ret;
}
urbp->req_id = id;
}
req = RING_GET_REQUEST(&info->urb_ring, info->urb_ring.req_prod_pvt);
*req = info->shadow[id].req;
info->urb_ring.req_prod_pvt++;
info->shadow[id].urb = urb;
info->shadow[id].in_flight = true;
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&info->urb_ring, notify);
if (notify)
notify_remote_via_irq(info->irq);
return 0;
}
static void xenhcd_kick_pending_urbs(struct xenhcd_info *info)
{
struct urb_priv *urbp;
while (!list_empty(&info->pending_submit_list)) {
if (RING_FULL(&info->urb_ring)) {
xenhcd_timer_action(info, TIMER_RING_WATCHDOG);
return;
}
urbp = list_entry(info->pending_submit_list.next,
struct urb_priv, list);
if (!xenhcd_do_request(info, urbp))
list_move_tail(&urbp->list, &info->in_progress_list);
else
xenhcd_giveback_urb(info, urbp->urb, -ESHUTDOWN);
}
xenhcd_timer_action_done(info, TIMER_SCAN_PENDING_URBS);
}
/*
* caller must lock info->lock
*/
static void xenhcd_cancel_all_enqueued_urbs(struct xenhcd_info *info)
{
struct urb_priv *urbp, *tmp;
int req_id;
list_for_each_entry_safe(urbp, tmp, &info->in_progress_list, list) {
req_id = urbp->req_id;
if (!urbp->unlinked) {
xenhcd_gnttab_done(info, req_id);
if (info->error)
return;
if (urbp->urb->status == -EINPROGRESS)
/* not dequeued */
xenhcd_giveback_urb(info, urbp->urb,
-ESHUTDOWN);
else /* dequeued */
xenhcd_giveback_urb(info, urbp->urb,
urbp->urb->status);
}
info->shadow[req_id].urb = NULL;
}
list_for_each_entry_safe(urbp, tmp, &info->pending_submit_list, list)
xenhcd_giveback_urb(info, urbp->urb, -ESHUTDOWN);
}
/*
* caller must lock info->lock
*/
static void xenhcd_giveback_unlinked_urbs(struct xenhcd_info *info)
{
struct urb_priv *urbp, *tmp;
list_for_each_entry_safe(urbp, tmp, &info->giveback_waiting_list, list)
xenhcd_giveback_urb(info, urbp->urb, urbp->urb->status);
}
static int xenhcd_submit_urb(struct xenhcd_info *info, struct urb_priv *urbp)
{
int ret;
if (RING_FULL(&info->urb_ring)) {
list_add_tail(&urbp->list, &info->pending_submit_list);
xenhcd_timer_action(info, TIMER_RING_WATCHDOG);
return 0;
}
if (!list_empty(&info->pending_submit_list)) {
list_add_tail(&urbp->list, &info->pending_submit_list);
xenhcd_timer_action(info, TIMER_SCAN_PENDING_URBS);
return 0;
}
ret = xenhcd_do_request(info, urbp);
if (ret == 0)
list_add_tail(&urbp->list, &info->in_progress_list);
return ret;
}
static int xenhcd_unlink_urb(struct xenhcd_info *info, struct urb_priv *urbp)
{
int ret;
/* already unlinked? */
if (urbp->unlinked)
return -EBUSY;
urbp->unlinked = true;
/* the urb is still in pending_submit queue */
if (urbp->req_id == ~0) {
list_move_tail(&urbp->list, &info->giveback_waiting_list);
xenhcd_timer_action(info, TIMER_SCAN_PENDING_URBS);
return 0;
}
/* send unlink request to backend */
if (RING_FULL(&info->urb_ring)) {
list_move_tail(&urbp->list, &info->pending_unlink_list);
xenhcd_timer_action(info, TIMER_RING_WATCHDOG);
return 0;
}
if (!list_empty(&info->pending_unlink_list)) {
list_move_tail(&urbp->list, &info->pending_unlink_list);
xenhcd_timer_action(info, TIMER_SCAN_PENDING_URBS);
return 0;
}
ret = xenhcd_do_request(info, urbp);
if (ret == 0)
list_move_tail(&urbp->list, &info->in_progress_list);
return ret;
}
static void xenhcd_res_to_urb(struct xenhcd_info *info,
struct xenusb_urb_response *res, struct urb *urb)
{
if (unlikely(!urb))
return;
if (res->actual_length > urb->transfer_buffer_length)
urb->actual_length = urb->transfer_buffer_length;
else if (res->actual_length < 0)
urb->actual_length = 0;
else
urb->actual_length = res->actual_length;
urb->error_count = res->error_count;
urb->start_frame = res->start_frame;
xenhcd_giveback_urb(info, urb, res->status);
}
static int xenhcd_urb_request_done(struct xenhcd_info *info,
unsigned int *eoiflag)
{
struct xenusb_urb_response res;
RING_IDX i, rp;
__u16 id;
int more_to_do = 0;
unsigned long flags;
spin_lock_irqsave(&info->lock, flags);
rp = info->urb_ring.sring->rsp_prod;
if (RING_RESPONSE_PROD_OVERFLOW(&info->urb_ring, rp)) {
xenhcd_set_error(info, "Illegal index on urb-ring");
goto err;
}
rmb(); /* ensure we see queued responses up to "rp" */
for (i = info->urb_ring.rsp_cons; i != rp; i++) {
RING_COPY_RESPONSE(&info->urb_ring, i, &res);
id = res.id;
if (id >= XENUSB_URB_RING_SIZE) {
xenhcd_set_error(info, "Illegal data on urb-ring");
goto err;
}
if (likely(xenusb_pipesubmit(info->shadow[id].req.pipe))) {
xenhcd_gnttab_done(info, id);
if (info->error)
goto err;
xenhcd_res_to_urb(info, &res, info->shadow[id].urb);
}
xenhcd_add_id_to_freelist(info, id);
*eoiflag = 0;
}
info->urb_ring.rsp_cons = i;
if (i != info->urb_ring.req_prod_pvt)
RING_FINAL_CHECK_FOR_RESPONSES(&info->urb_ring, more_to_do);
else
info->urb_ring.sring->rsp_event = i + 1;
spin_unlock_irqrestore(&info->lock, flags);
return more_to_do;
err:
spin_unlock_irqrestore(&info->lock, flags);
return 0;
}
static int xenhcd_conn_notify(struct xenhcd_info *info, unsigned int *eoiflag)
{
struct xenusb_conn_response res;
struct xenusb_conn_request *req;
RING_IDX rc, rp;
__u16 id;
__u8 portnum, speed;
int more_to_do = 0;
int notify;
int port_changed = 0;
unsigned long flags;
spin_lock_irqsave(&info->lock, flags);
rc = info->conn_ring.rsp_cons;
rp = info->conn_ring.sring->rsp_prod;
if (RING_RESPONSE_PROD_OVERFLOW(&info->conn_ring, rp)) {
xenhcd_set_error(info, "Illegal index on conn-ring");
spin_unlock_irqrestore(&info->lock, flags);
return 0;
}
rmb(); /* ensure we see queued responses up to "rp" */
while (rc != rp) {
RING_COPY_RESPONSE(&info->conn_ring, rc, &res);
id = res.id;
portnum = res.portnum;
speed = res.speed;
info->conn_ring.rsp_cons = ++rc;
if (xenhcd_rhport_connect(info, portnum, speed)) {
xenhcd_set_error(info, "Illegal data on conn-ring");
spin_unlock_irqrestore(&info->lock, flags);
return 0;
}
if (info->ports[portnum - 1].c_connection)
port_changed = 1;
barrier();
req = RING_GET_REQUEST(&info->conn_ring,
info->conn_ring.req_prod_pvt);
req->id = id;
info->conn_ring.req_prod_pvt++;
*eoiflag = 0;
}
if (rc != info->conn_ring.req_prod_pvt)
RING_FINAL_CHECK_FOR_RESPONSES(&info->conn_ring, more_to_do);
else
info->conn_ring.sring->rsp_event = rc + 1;
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&info->conn_ring, notify);
if (notify)
notify_remote_via_irq(info->irq);
spin_unlock_irqrestore(&info->lock, flags);
if (port_changed)
usb_hcd_poll_rh_status(xenhcd_info_to_hcd(info));
return more_to_do;
}
static irqreturn_t xenhcd_int(int irq, void *dev_id)
{
struct xenhcd_info *info = (struct xenhcd_info *)dev_id;
unsigned int eoiflag = XEN_EOI_FLAG_SPURIOUS;
if (unlikely(info->error)) {
xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS);
return IRQ_HANDLED;
}
while (xenhcd_urb_request_done(info, &eoiflag) |
xenhcd_conn_notify(info, &eoiflag))
/* Yield point for this unbounded loop. */
cond_resched();
xen_irq_lateeoi(irq, eoiflag);
return IRQ_HANDLED;
}
static void xenhcd_destroy_rings(struct xenhcd_info *info)
{
if (info->irq)
unbind_from_irqhandler(info->irq, info);
info->irq = 0;
xenbus_teardown_ring((void **)&info->urb_ring.sring, 1,
&info->urb_ring_ref);
xenbus_teardown_ring((void **)&info->conn_ring.sring, 1,
&info->conn_ring_ref);
}
static int xenhcd_setup_rings(struct xenbus_device *dev,
struct xenhcd_info *info)
{
struct xenusb_urb_sring *urb_sring;
struct xenusb_conn_sring *conn_sring;
int err;
info->conn_ring_ref = INVALID_GRANT_REF;
err = xenbus_setup_ring(dev, GFP_NOIO | __GFP_HIGH,
(void **)&urb_sring, 1, &info->urb_ring_ref);
if (err) {
xenbus_dev_fatal(dev, err, "allocating urb ring");
return err;
}
XEN_FRONT_RING_INIT(&info->urb_ring, urb_sring, PAGE_SIZE);
err = xenbus_setup_ring(dev, GFP_NOIO | __GFP_HIGH,
(void **)&conn_sring, 1, &info->conn_ring_ref);
if (err) {
xenbus_dev_fatal(dev, err, "allocating conn ring");
goto fail;
}
XEN_FRONT_RING_INIT(&info->conn_ring, conn_sring, PAGE_SIZE);
err = xenbus_alloc_evtchn(dev, &info->evtchn);
if (err) {
xenbus_dev_fatal(dev, err, "xenbus_alloc_evtchn");
goto fail;
}
err = bind_evtchn_to_irq_lateeoi(info->evtchn);
if (err <= 0) {
xenbus_dev_fatal(dev, err, "bind_evtchn_to_irq_lateeoi");
goto fail;
}
info->irq = err;
err = request_threaded_irq(info->irq, NULL, xenhcd_int,
IRQF_ONESHOT, "xenhcd", info);
if (err) {
xenbus_dev_fatal(dev, err, "request_threaded_irq");
goto free_irq;
}
return 0;
free_irq:
unbind_from_irqhandler(info->irq, info);
fail:
xenhcd_destroy_rings(info);
return err;
}
static int xenhcd_talk_to_backend(struct xenbus_device *dev,
struct xenhcd_info *info)
{
const char *message;
struct xenbus_transaction xbt;
int err;
err = xenhcd_setup_rings(dev, info);
if (err)
return err;
again:
err = xenbus_transaction_start(&xbt);
if (err) {
xenbus_dev_fatal(dev, err, "starting transaction");
goto destroy_ring;
}
err = xenbus_printf(xbt, dev->nodename, "urb-ring-ref", "%u",
info->urb_ring_ref);
if (err) {
message = "writing urb-ring-ref";
goto abort_transaction;
}
err = xenbus_printf(xbt, dev->nodename, "conn-ring-ref", "%u",
info->conn_ring_ref);
if (err) {
message = "writing conn-ring-ref";
goto abort_transaction;
}
err = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
info->evtchn);
if (err) {
message = "writing event-channel";
goto abort_transaction;
}
err = xenbus_transaction_end(xbt, 0);
if (err) {
if (err == -EAGAIN)
goto again;
xenbus_dev_fatal(dev, err, "completing transaction");
goto destroy_ring;
}
return 0;
abort_transaction:
xenbus_transaction_end(xbt, 1);
xenbus_dev_fatal(dev, err, "%s", message);
destroy_ring:
xenhcd_destroy_rings(info);
return err;
}
static int xenhcd_connect(struct xenbus_device *dev)
{
struct xenhcd_info *info = dev_get_drvdata(&dev->dev);
struct xenusb_conn_request *req;
int idx, err;
int notify;
char name[TASK_COMM_LEN];
struct usb_hcd *hcd;
hcd = xenhcd_info_to_hcd(info);
snprintf(name, TASK_COMM_LEN, "xenhcd.%d", hcd->self.busnum);
err = xenhcd_talk_to_backend(dev, info);
if (err)
return err;
/* prepare ring for hotplug notification */
for (idx = 0; idx < XENUSB_CONN_RING_SIZE; idx++) {
req = RING_GET_REQUEST(&info->conn_ring, idx);
req->id = idx;
}
info->conn_ring.req_prod_pvt = idx;
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&info->conn_ring, notify);
if (notify)
notify_remote_via_irq(info->irq);
return 0;
}
static void xenhcd_disconnect(struct xenbus_device *dev)
{
struct xenhcd_info *info = dev_get_drvdata(&dev->dev);
struct usb_hcd *hcd = xenhcd_info_to_hcd(info);
usb_remove_hcd(hcd);
xenbus_frontend_closed(dev);
}
static void xenhcd_watchdog(struct timer_list *timer)
{
struct xenhcd_info *info = from_timer(info, timer, watchdog);
unsigned long flags;
spin_lock_irqsave(&info->lock, flags);
if (likely(HC_IS_RUNNING(xenhcd_info_to_hcd(info)->state))) {
xenhcd_timer_action_done(info, TIMER_RING_WATCHDOG);
xenhcd_giveback_unlinked_urbs(info);
xenhcd_kick_pending_urbs(info);
}
spin_unlock_irqrestore(&info->lock, flags);
}
/*
* one-time HC init
*/
static int xenhcd_setup(struct usb_hcd *hcd)
{
struct xenhcd_info *info = xenhcd_hcd_to_info(hcd);
spin_lock_init(&info->lock);
INIT_LIST_HEAD(&info->pending_submit_list);
INIT_LIST_HEAD(&info->pending_unlink_list);
INIT_LIST_HEAD(&info->in_progress_list);
INIT_LIST_HEAD(&info->giveback_waiting_list);
timer_setup(&info->watchdog, xenhcd_watchdog, 0);
hcd->has_tt = (hcd->driver->flags & HCD_MASK) != HCD_USB11;
return 0;
}
/*
* start HC running
*/
static int xenhcd_run(struct usb_hcd *hcd)
{
hcd->uses_new_polling = 1;
clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
hcd->state = HC_STATE_RUNNING;
return 0;
}
/*
* stop running HC
*/
static void xenhcd_stop(struct usb_hcd *hcd)
{
struct xenhcd_info *info = xenhcd_hcd_to_info(hcd);
del_timer_sync(&info->watchdog);
spin_lock_irq(&info->lock);
/* cancel all urbs */
hcd->state = HC_STATE_HALT;
xenhcd_cancel_all_enqueued_urbs(info);
xenhcd_giveback_unlinked_urbs(info);
spin_unlock_irq(&info->lock);
}
/*
* called as .urb_enqueue()
* non-error returns are promise to giveback the urb later
*/
static int xenhcd_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
gfp_t mem_flags)
{
struct xenhcd_info *info = xenhcd_hcd_to_info(hcd);
struct urb_priv *urbp;
unsigned long flags;
int ret;
if (unlikely(info->error))
return -ESHUTDOWN;
urbp = kmem_cache_zalloc(xenhcd_urbp_cachep, mem_flags);
if (!urbp)
return -ENOMEM;
spin_lock_irqsave(&info->lock, flags);
urbp->urb = urb;
urb->hcpriv = urbp;
urbp->req_id = ~0;
urbp->unlink_req_id = ~0;
INIT_LIST_HEAD(&urbp->list);
urbp->status = 1;
urb->unlinked = false;
ret = xenhcd_submit_urb(info, urbp);
if (ret)
xenhcd_free_urb_priv(urbp);
spin_unlock_irqrestore(&info->lock, flags);
return ret;
}
/*
* called as .urb_dequeue()
*/
static int xenhcd_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
{
struct xenhcd_info *info = xenhcd_hcd_to_info(hcd);
struct urb_priv *urbp;
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&info->lock, flags);
urbp = urb->hcpriv;
if (urbp) {
urbp->status = status;
ret = xenhcd_unlink_urb(info, urbp);
}
spin_unlock_irqrestore(&info->lock, flags);
return ret;
}
/*
* called from usb_get_current_frame_number(),
* but, almost all drivers not use such function.
*/
static int xenhcd_get_frame(struct usb_hcd *hcd)
{
/* it means error, but probably no problem :-) */
return 0;
}
static struct hc_driver xenhcd_usb20_hc_driver = {
.description = "xen-hcd",
.product_desc = "Xen USB2.0 Virtual Host Controller",
.hcd_priv_size = sizeof(struct xenhcd_info),
.flags = HCD_USB2,
/* basic HC lifecycle operations */
.reset = xenhcd_setup,
.start = xenhcd_run,
.stop = xenhcd_stop,
/* managing urb I/O */
.urb_enqueue = xenhcd_urb_enqueue,
.urb_dequeue = xenhcd_urb_dequeue,
.get_frame_number = xenhcd_get_frame,
/* root hub operations */
.hub_status_data = xenhcd_hub_status_data,
.hub_control = xenhcd_hub_control,
#ifdef CONFIG_PM
.bus_suspend = xenhcd_bus_suspend,
.bus_resume = xenhcd_bus_resume,
#endif
};
static struct hc_driver xenhcd_usb11_hc_driver = {
.description = "xen-hcd",
.product_desc = "Xen USB1.1 Virtual Host Controller",
.hcd_priv_size = sizeof(struct xenhcd_info),
.flags = HCD_USB11,
/* basic HC lifecycle operations */
.reset = xenhcd_setup,
.start = xenhcd_run,
.stop = xenhcd_stop,
/* managing urb I/O */
.urb_enqueue = xenhcd_urb_enqueue,
.urb_dequeue = xenhcd_urb_dequeue,
.get_frame_number = xenhcd_get_frame,
/* root hub operations */
.hub_status_data = xenhcd_hub_status_data,
.hub_control = xenhcd_hub_control,
#ifdef CONFIG_PM
.bus_suspend = xenhcd_bus_suspend,
.bus_resume = xenhcd_bus_resume,
#endif
};
static struct usb_hcd *xenhcd_create_hcd(struct xenbus_device *dev)
{
int i;
int err = 0;
int num_ports;
int usb_ver;
struct usb_hcd *hcd = NULL;
struct xenhcd_info *info;
err = xenbus_scanf(XBT_NIL, dev->otherend, "num-ports", "%d",
&num_ports);
if (err != 1) {
xenbus_dev_fatal(dev, err, "reading num-ports");
return ERR_PTR(-EINVAL);
}
if (num_ports < 1 || num_ports > XENUSB_MAX_PORTNR) {
xenbus_dev_fatal(dev, err, "invalid num-ports");
return ERR_PTR(-EINVAL);
}
err = xenbus_scanf(XBT_NIL, dev->otherend, "usb-ver", "%d", &usb_ver);
if (err != 1) {
xenbus_dev_fatal(dev, err, "reading usb-ver");
return ERR_PTR(-EINVAL);
}
switch (usb_ver) {
case XENUSB_VER_USB11:
hcd = usb_create_hcd(&xenhcd_usb11_hc_driver, &dev->dev,
dev_name(&dev->dev));
break;
case XENUSB_VER_USB20:
hcd = usb_create_hcd(&xenhcd_usb20_hc_driver, &dev->dev,
dev_name(&dev->dev));
break;
default:
xenbus_dev_fatal(dev, err, "invalid usb-ver");
return ERR_PTR(-EINVAL);
}
if (!hcd) {
xenbus_dev_fatal(dev, err,
"fail to allocate USB host controller");
return ERR_PTR(-ENOMEM);
}
info = xenhcd_hcd_to_info(hcd);
info->xbdev = dev;
info->rh_numports = num_ports;
for (i = 0; i < XENUSB_URB_RING_SIZE; i++) {
info->shadow[i].req.id = i + 1;
info->shadow[i].urb = NULL;
info->shadow[i].in_flight = false;
}
info->shadow[XENUSB_URB_RING_SIZE - 1].req.id = 0x0fff;
return hcd;
}
static void xenhcd_backend_changed(struct xenbus_device *dev,
enum xenbus_state backend_state)
{
switch (backend_state) {
case XenbusStateInitialising:
case XenbusStateReconfiguring:
case XenbusStateReconfigured:
case XenbusStateUnknown:
break;
case XenbusStateInitWait:
case XenbusStateInitialised:
case XenbusStateConnected:
if (dev->state != XenbusStateInitialising)
break;
if (!xenhcd_connect(dev))
xenbus_switch_state(dev, XenbusStateConnected);
break;
case XenbusStateClosed:
if (dev->state == XenbusStateClosed)
break;
fallthrough; /* Missed the backend's Closing state. */
case XenbusStateClosing:
xenhcd_disconnect(dev);
break;
default:
xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
backend_state);
break;
}
}
static void xenhcd_remove(struct xenbus_device *dev)
{
struct xenhcd_info *info = dev_get_drvdata(&dev->dev);
struct usb_hcd *hcd = xenhcd_info_to_hcd(info);
xenhcd_destroy_rings(info);
usb_put_hcd(hcd);
}
static int xenhcd_probe(struct xenbus_device *dev,
const struct xenbus_device_id *id)
{
int err;
struct usb_hcd *hcd;
struct xenhcd_info *info;
if (usb_disabled())
return -ENODEV;
hcd = xenhcd_create_hcd(dev);
if (IS_ERR(hcd)) {
err = PTR_ERR(hcd);
xenbus_dev_fatal(dev, err,
"fail to create usb host controller");
return err;
}
info = xenhcd_hcd_to_info(hcd);
dev_set_drvdata(&dev->dev, info);
err = usb_add_hcd(hcd, 0, 0);
if (err) {
xenbus_dev_fatal(dev, err, "fail to add USB host controller");
usb_put_hcd(hcd);
dev_set_drvdata(&dev->dev, NULL);
}
return err;
}
static const struct xenbus_device_id xenhcd_ids[] = {
{ "vusb" },
{ "" },
};
static struct xenbus_driver xenhcd_driver = {
.ids = xenhcd_ids,
.probe = xenhcd_probe,
.otherend_changed = xenhcd_backend_changed,
.remove = xenhcd_remove,
};
static int __init xenhcd_init(void)
{
if (!xen_domain())
return -ENODEV;
xenhcd_urbp_cachep = kmem_cache_create("xenhcd_urb_priv",
sizeof(struct urb_priv), 0, 0, NULL);
if (!xenhcd_urbp_cachep) {
pr_err("xenhcd failed to create kmem cache\n");
return -ENOMEM;
}
return xenbus_register_frontend(&xenhcd_driver);
}
module_init(xenhcd_init);
static void __exit xenhcd_exit(void)
{
kmem_cache_destroy(xenhcd_urbp_cachep);
xenbus_unregister_driver(&xenhcd_driver);
}
module_exit(xenhcd_exit);
MODULE_ALIAS("xen:vusb");
MODULE_AUTHOR("Juergen Gross <[email protected]>");
MODULE_DESCRIPTION("Xen USB Virtual Host Controller driver (xen-hcd)");
MODULE_LICENSE("Dual BSD/GPL");
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