diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/usb/host/xen-hcd.c | 1613 |
1 files changed, 1613 insertions, 0 deletions
diff --git a/drivers/usb/host/xen-hcd.c b/drivers/usb/host/xen-hcd.c new file mode 100644 index 000000000..de1b09158 --- /dev/null +++ b/drivers/usb/host/xen-hcd.c @@ -0,0 +1,1613 @@ +// 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 <n_iwamatsu@jp.fujitsu.com> + */ + +#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 int 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); + + return 0; +} + +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 <jgross@suse.com>"); +MODULE_DESCRIPTION("Xen USB Virtual Host Controller driver (xen-hcd)"); +MODULE_LICENSE("Dual BSD/GPL"); |