diff options
Diffstat (limited to 'drivers/usb/usbip/vhci_rx.c')
| -rw-r--r-- | drivers/usb/usbip/vhci_rx.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/drivers/usb/usbip/vhci_rx.c b/drivers/usb/usbip/vhci_rx.c new file mode 100644 index 000000000..7f2d1c241 --- /dev/null +++ b/drivers/usb/usbip/vhci_rx.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2003-2008 Takahiro Hirofuchi + */ + +#include <linux/kthread.h> +#include <linux/slab.h> + +#include "usbip_common.h" +#include "vhci.h" + +/* get URB from transmitted urb queue. caller must hold vdev->priv_lock */ +struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev, __u32 seqnum) +{ + struct vhci_priv *priv, *tmp; + struct urb *urb = NULL; + int status; + + list_for_each_entry_safe(priv, tmp, &vdev->priv_rx, list) { + if (priv->seqnum != seqnum) + continue; + + urb = priv->urb; + status = urb->status; + + usbip_dbg_vhci_rx("find urb seqnum %u\n", seqnum); + + switch (status) { + case -ENOENT: + fallthrough; + case -ECONNRESET: + dev_dbg(&urb->dev->dev, + "urb seq# %u was unlinked %ssynchronously\n", + seqnum, status == -ENOENT ? "" : "a"); + break; + case -EINPROGRESS: + /* no info output */ + break; + default: + dev_dbg(&urb->dev->dev, + "urb seq# %u may be in a error, status %d\n", + seqnum, status); + } + + list_del(&priv->list); + kfree(priv); + urb->hcpriv = NULL; + + break; + } + + return urb; +} + +static void vhci_recv_ret_submit(struct vhci_device *vdev, + struct usbip_header *pdu) +{ + struct vhci_hcd *vhci_hcd = vdev_to_vhci_hcd(vdev); + struct vhci *vhci = vhci_hcd->vhci; + struct usbip_device *ud = &vdev->ud; + struct urb *urb; + unsigned long flags; + + spin_lock_irqsave(&vdev->priv_lock, flags); + urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum); + spin_unlock_irqrestore(&vdev->priv_lock, flags); + + if (!urb) { + pr_err("cannot find a urb of seqnum %u max seqnum %d\n", + pdu->base.seqnum, + atomic_read(&vhci_hcd->seqnum)); + usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); + return; + } + + /* unpack the pdu to a urb */ + usbip_pack_pdu(pdu, urb, USBIP_RET_SUBMIT, 0); + + /* recv transfer buffer */ + if (usbip_recv_xbuff(ud, urb) < 0) { + urb->status = -EPROTO; + goto error; + } + + /* recv iso_packet_descriptor */ + if (usbip_recv_iso(ud, urb) < 0) { + urb->status = -EPROTO; + goto error; + } + + /* restore the padding in iso packets */ + usbip_pad_iso(ud, urb); + +error: + if (usbip_dbg_flag_vhci_rx) + usbip_dump_urb(urb); + + if (urb->num_sgs) + urb->transfer_flags &= ~URB_DMA_MAP_SG; + + usbip_dbg_vhci_rx("now giveback urb %u\n", pdu->base.seqnum); + + spin_lock_irqsave(&vhci->lock, flags); + usb_hcd_unlink_urb_from_ep(vhci_hcd_to_hcd(vhci_hcd), urb); + spin_unlock_irqrestore(&vhci->lock, flags); + + usb_hcd_giveback_urb(vhci_hcd_to_hcd(vhci_hcd), urb, urb->status); + + usbip_dbg_vhci_rx("Leave\n"); +} + +static struct vhci_unlink *dequeue_pending_unlink(struct vhci_device *vdev, + struct usbip_header *pdu) +{ + struct vhci_unlink *unlink, *tmp; + unsigned long flags; + + spin_lock_irqsave(&vdev->priv_lock, flags); + + list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) { + pr_info("unlink->seqnum %lu\n", unlink->seqnum); + if (unlink->seqnum == pdu->base.seqnum) { + usbip_dbg_vhci_rx("found pending unlink, %lu\n", + unlink->seqnum); + list_del(&unlink->list); + + spin_unlock_irqrestore(&vdev->priv_lock, flags); + return unlink; + } + } + + spin_unlock_irqrestore(&vdev->priv_lock, flags); + + return NULL; +} + +static void vhci_recv_ret_unlink(struct vhci_device *vdev, + struct usbip_header *pdu) +{ + struct vhci_hcd *vhci_hcd = vdev_to_vhci_hcd(vdev); + struct vhci *vhci = vhci_hcd->vhci; + struct vhci_unlink *unlink; + struct urb *urb; + unsigned long flags; + + usbip_dump_header(pdu); + + unlink = dequeue_pending_unlink(vdev, pdu); + if (!unlink) { + pr_info("cannot find the pending unlink %u\n", + pdu->base.seqnum); + return; + } + + spin_lock_irqsave(&vdev->priv_lock, flags); + urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum); + spin_unlock_irqrestore(&vdev->priv_lock, flags); + + if (!urb) { + /* + * I get the result of a unlink request. But, it seems that I + * already received the result of its submit result and gave + * back the URB. + */ + pr_info("the urb (seqnum %d) was already given back\n", + pdu->base.seqnum); + } else { + usbip_dbg_vhci_rx("now giveback urb %d\n", pdu->base.seqnum); + + /* If unlink is successful, status is -ECONNRESET */ + urb->status = pdu->u.ret_unlink.status; + pr_info("urb->status %d\n", urb->status); + + spin_lock_irqsave(&vhci->lock, flags); + usb_hcd_unlink_urb_from_ep(vhci_hcd_to_hcd(vhci_hcd), urb); + spin_unlock_irqrestore(&vhci->lock, flags); + + usb_hcd_giveback_urb(vhci_hcd_to_hcd(vhci_hcd), urb, urb->status); + } + + kfree(unlink); +} + +static int vhci_priv_tx_empty(struct vhci_device *vdev) +{ + int empty = 0; + unsigned long flags; + + spin_lock_irqsave(&vdev->priv_lock, flags); + empty = list_empty(&vdev->priv_rx); + spin_unlock_irqrestore(&vdev->priv_lock, flags); + + return empty; +} + +/* recv a pdu */ +static void vhci_rx_pdu(struct usbip_device *ud) +{ + int ret; + struct usbip_header pdu; + struct vhci_device *vdev = container_of(ud, struct vhci_device, ud); + + usbip_dbg_vhci_rx("Enter\n"); + + memset(&pdu, 0, sizeof(pdu)); + + /* receive a pdu header */ + ret = usbip_recv(ud->tcp_socket, &pdu, sizeof(pdu)); + if (ret < 0) { + if (ret == -ECONNRESET) + pr_info("connection reset by peer\n"); + else if (ret == -EAGAIN) { + /* ignore if connection was idle */ + if (vhci_priv_tx_empty(vdev)) + return; + pr_info("connection timed out with pending urbs\n"); + } else if (ret != -ERESTARTSYS) + pr_info("xmit failed %d\n", ret); + + usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); + return; + } + if (ret == 0) { + pr_info("connection closed"); + usbip_event_add(ud, VDEV_EVENT_DOWN); + return; + } + if (ret != sizeof(pdu)) { + pr_err("received pdu size is %d, should be %d\n", ret, + (unsigned int)sizeof(pdu)); + usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); + return; + } + + usbip_header_correct_endian(&pdu, 0); + + if (usbip_dbg_flag_vhci_rx) + usbip_dump_header(&pdu); + + switch (pdu.base.command) { + case USBIP_RET_SUBMIT: + vhci_recv_ret_submit(vdev, &pdu); + break; + case USBIP_RET_UNLINK: + vhci_recv_ret_unlink(vdev, &pdu); + break; + default: + /* NOT REACHED */ + pr_err("unknown pdu %u\n", pdu.base.command); + usbip_dump_header(&pdu); + usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); + break; + } +} + +int vhci_rx_loop(void *data) +{ + struct usbip_device *ud = data; + + while (!kthread_should_stop()) { + if (usbip_event_happened(ud)) + break; + + usbip_kcov_remote_start(ud); + vhci_rx_pdu(ud); + usbip_kcov_remote_stop(); + } + + return 0; +} |