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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/usb/usbip/stub_tx.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/usbip/stub_tx.c')
-rw-r--r-- | drivers/usb/usbip/stub_tx.c | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/drivers/usb/usbip/stub_tx.c b/drivers/usb/usbip/stub_tx.c new file mode 100644 index 000000000..36010a82b --- /dev/null +++ b/drivers/usb/usbip/stub_tx.c @@ -0,0 +1,453 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2003-2008 Takahiro Hirofuchi + */ + +#include <linux/kthread.h> +#include <linux/socket.h> +#include <linux/scatterlist.h> + +#include "usbip_common.h" +#include "stub.h" + +/* be in spin_lock_irqsave(&sdev->priv_lock, flags) */ +void stub_enqueue_ret_unlink(struct stub_device *sdev, __u32 seqnum, + __u32 status) +{ + struct stub_unlink *unlink; + + unlink = kzalloc(sizeof(struct stub_unlink), GFP_ATOMIC); + if (!unlink) { + usbip_event_add(&sdev->ud, VDEV_EVENT_ERROR_MALLOC); + return; + } + + unlink->seqnum = seqnum; + unlink->status = status; + + list_add_tail(&unlink->list, &sdev->unlink_tx); +} + +/** + * stub_complete - completion handler of a usbip urb + * @urb: pointer to the urb completed + * + * When a urb has completed, the USB core driver calls this function mostly in + * the interrupt context. To return the result of a urb, the completed urb is + * linked to the pending list of returning. + * + */ +void stub_complete(struct urb *urb) +{ + struct stub_priv *priv = (struct stub_priv *) urb->context; + struct stub_device *sdev = priv->sdev; + unsigned long flags; + + usbip_dbg_stub_tx("complete! status %d\n", urb->status); + + switch (urb->status) { + case 0: + /* OK */ + break; + case -ENOENT: + dev_info(&urb->dev->dev, + "stopped by a call to usb_kill_urb() because of cleaning up a virtual connection\n"); + return; + case -ECONNRESET: + dev_info(&urb->dev->dev, + "unlinked by a call to usb_unlink_urb()\n"); + break; + case -EPIPE: + dev_info(&urb->dev->dev, "endpoint %d is stalled\n", + usb_pipeendpoint(urb->pipe)); + break; + case -ESHUTDOWN: + dev_info(&urb->dev->dev, "device removed?\n"); + break; + default: + dev_info(&urb->dev->dev, + "urb completion with non-zero status %d\n", + urb->status); + break; + } + + /* + * If the server breaks single SG request into the several URBs, the + * URBs must be reassembled before sending completed URB to the vhci. + * Don't wake up the tx thread until all the URBs are completed. + */ + if (priv->sgl) { + priv->completed_urbs++; + + /* Only save the first error status */ + if (urb->status && !priv->urb_status) + priv->urb_status = urb->status; + + if (priv->completed_urbs < priv->num_urbs) + return; + } + + /* link a urb to the queue of tx. */ + spin_lock_irqsave(&sdev->priv_lock, flags); + if (sdev->ud.tcp_socket == NULL) { + usbip_dbg_stub_tx("ignore urb for closed connection\n"); + /* It will be freed in stub_device_cleanup_urbs(). */ + } else if (priv->unlinking) { + stub_enqueue_ret_unlink(sdev, priv->seqnum, urb->status); + stub_free_priv_and_urb(priv); + } else { + list_move_tail(&priv->list, &sdev->priv_tx); + } + spin_unlock_irqrestore(&sdev->priv_lock, flags); + + /* wake up tx_thread */ + wake_up(&sdev->tx_waitq); +} + +static inline void setup_base_pdu(struct usbip_header_basic *base, + __u32 command, __u32 seqnum) +{ + base->command = command; + base->seqnum = seqnum; + base->devid = 0; + base->ep = 0; + base->direction = 0; +} + +static void setup_ret_submit_pdu(struct usbip_header *rpdu, struct urb *urb) +{ + struct stub_priv *priv = (struct stub_priv *) urb->context; + + setup_base_pdu(&rpdu->base, USBIP_RET_SUBMIT, priv->seqnum); + usbip_pack_pdu(rpdu, urb, USBIP_RET_SUBMIT, 1); +} + +static void setup_ret_unlink_pdu(struct usbip_header *rpdu, + struct stub_unlink *unlink) +{ + setup_base_pdu(&rpdu->base, USBIP_RET_UNLINK, unlink->seqnum); + rpdu->u.ret_unlink.status = unlink->status; +} + +static struct stub_priv *dequeue_from_priv_tx(struct stub_device *sdev) +{ + unsigned long flags; + struct stub_priv *priv, *tmp; + + spin_lock_irqsave(&sdev->priv_lock, flags); + + list_for_each_entry_safe(priv, tmp, &sdev->priv_tx, list) { + list_move_tail(&priv->list, &sdev->priv_free); + spin_unlock_irqrestore(&sdev->priv_lock, flags); + return priv; + } + + spin_unlock_irqrestore(&sdev->priv_lock, flags); + + return NULL; +} + +static int stub_send_ret_submit(struct stub_device *sdev) +{ + unsigned long flags; + struct stub_priv *priv, *tmp; + + struct msghdr msg; + size_t txsize; + + size_t total_size = 0; + + while ((priv = dequeue_from_priv_tx(sdev)) != NULL) { + struct urb *urb = priv->urbs[0]; + struct usbip_header pdu_header; + struct usbip_iso_packet_descriptor *iso_buffer = NULL; + struct kvec *iov = NULL; + struct scatterlist *sg; + u32 actual_length = 0; + int iovnum = 0; + int ret; + int i; + + txsize = 0; + memset(&pdu_header, 0, sizeof(pdu_header)); + memset(&msg, 0, sizeof(msg)); + + if (urb->actual_length > 0 && !urb->transfer_buffer && + !urb->num_sgs) { + dev_err(&sdev->udev->dev, + "urb: actual_length %d transfer_buffer null\n", + urb->actual_length); + return -1; + } + + if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) + iovnum = 2 + urb->number_of_packets; + else if (usb_pipein(urb->pipe) && urb->actual_length > 0 && + urb->num_sgs) + iovnum = 1 + urb->num_sgs; + else if (usb_pipein(urb->pipe) && priv->sgl) + iovnum = 1 + priv->num_urbs; + else + iovnum = 2; + + iov = kcalloc(iovnum, sizeof(struct kvec), GFP_KERNEL); + + if (!iov) { + usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_MALLOC); + return -1; + } + + iovnum = 0; + + /* 1. setup usbip_header */ + setup_ret_submit_pdu(&pdu_header, urb); + usbip_dbg_stub_tx("setup txdata seqnum: %d\n", + pdu_header.base.seqnum); + + if (priv->sgl) { + for (i = 0; i < priv->num_urbs; i++) + actual_length += priv->urbs[i]->actual_length; + + pdu_header.u.ret_submit.status = priv->urb_status; + pdu_header.u.ret_submit.actual_length = actual_length; + } + + usbip_header_correct_endian(&pdu_header, 1); + + iov[iovnum].iov_base = &pdu_header; + iov[iovnum].iov_len = sizeof(pdu_header); + iovnum++; + txsize += sizeof(pdu_header); + + /* 2. setup transfer buffer */ + if (usb_pipein(urb->pipe) && priv->sgl) { + /* If the server split a single SG request into several + * URBs because the server's HCD doesn't support SG, + * reassemble the split URB buffers into a single + * return command. + */ + for (i = 0; i < priv->num_urbs; i++) { + iov[iovnum].iov_base = + priv->urbs[i]->transfer_buffer; + iov[iovnum].iov_len = + priv->urbs[i]->actual_length; + iovnum++; + } + txsize += actual_length; + } else if (usb_pipein(urb->pipe) && + usb_pipetype(urb->pipe) != PIPE_ISOCHRONOUS && + urb->actual_length > 0) { + if (urb->num_sgs) { + unsigned int copy = urb->actual_length; + int size; + + for_each_sg(urb->sg, sg, urb->num_sgs, i) { + if (copy == 0) + break; + + if (copy < sg->length) + size = copy; + else + size = sg->length; + + iov[iovnum].iov_base = sg_virt(sg); + iov[iovnum].iov_len = size; + + iovnum++; + copy -= size; + } + } else { + iov[iovnum].iov_base = urb->transfer_buffer; + iov[iovnum].iov_len = urb->actual_length; + iovnum++; + } + txsize += urb->actual_length; + } else if (usb_pipein(urb->pipe) && + usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) { + /* + * For isochronous packets: actual length is the sum of + * the actual length of the individual, packets, but as + * the packet offsets are not changed there will be + * padding between the packets. To optimally use the + * bandwidth the padding is not transmitted. + */ + + int i; + + for (i = 0; i < urb->number_of_packets; i++) { + iov[iovnum].iov_base = urb->transfer_buffer + + urb->iso_frame_desc[i].offset; + iov[iovnum].iov_len = + urb->iso_frame_desc[i].actual_length; + iovnum++; + txsize += urb->iso_frame_desc[i].actual_length; + } + + if (txsize != sizeof(pdu_header) + urb->actual_length) { + dev_err(&sdev->udev->dev, + "actual length of urb %d does not match iso packet sizes %zu\n", + urb->actual_length, + txsize-sizeof(pdu_header)); + kfree(iov); + usbip_event_add(&sdev->ud, + SDEV_EVENT_ERROR_TCP); + return -1; + } + } + + /* 3. setup iso_packet_descriptor */ + if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) { + ssize_t len = 0; + + iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len); + if (!iso_buffer) { + usbip_event_add(&sdev->ud, + SDEV_EVENT_ERROR_MALLOC); + kfree(iov); + return -1; + } + + iov[iovnum].iov_base = iso_buffer; + iov[iovnum].iov_len = len; + txsize += len; + iovnum++; + } + + ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, + iov, iovnum, txsize); + if (ret != txsize) { + dev_err(&sdev->udev->dev, + "sendmsg failed!, retval %d for %zd\n", + ret, txsize); + kfree(iov); + kfree(iso_buffer); + usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP); + return -1; + } + + kfree(iov); + kfree(iso_buffer); + + total_size += txsize; + } + + spin_lock_irqsave(&sdev->priv_lock, flags); + list_for_each_entry_safe(priv, tmp, &sdev->priv_free, list) { + stub_free_priv_and_urb(priv); + } + spin_unlock_irqrestore(&sdev->priv_lock, flags); + + return total_size; +} + +static struct stub_unlink *dequeue_from_unlink_tx(struct stub_device *sdev) +{ + unsigned long flags; + struct stub_unlink *unlink, *tmp; + + spin_lock_irqsave(&sdev->priv_lock, flags); + + list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) { + list_move_tail(&unlink->list, &sdev->unlink_free); + spin_unlock_irqrestore(&sdev->priv_lock, flags); + return unlink; + } + + spin_unlock_irqrestore(&sdev->priv_lock, flags); + + return NULL; +} + +static int stub_send_ret_unlink(struct stub_device *sdev) +{ + unsigned long flags; + struct stub_unlink *unlink, *tmp; + + struct msghdr msg; + struct kvec iov[1]; + size_t txsize; + + size_t total_size = 0; + + while ((unlink = dequeue_from_unlink_tx(sdev)) != NULL) { + int ret; + struct usbip_header pdu_header; + + txsize = 0; + memset(&pdu_header, 0, sizeof(pdu_header)); + memset(&msg, 0, sizeof(msg)); + memset(&iov, 0, sizeof(iov)); + + usbip_dbg_stub_tx("setup ret unlink %lu\n", unlink->seqnum); + + /* 1. setup usbip_header */ + setup_ret_unlink_pdu(&pdu_header, unlink); + usbip_header_correct_endian(&pdu_header, 1); + + iov[0].iov_base = &pdu_header; + iov[0].iov_len = sizeof(pdu_header); + txsize += sizeof(pdu_header); + + ret = kernel_sendmsg(sdev->ud.tcp_socket, &msg, iov, + 1, txsize); + if (ret != txsize) { + dev_err(&sdev->udev->dev, + "sendmsg failed!, retval %d for %zd\n", + ret, txsize); + usbip_event_add(&sdev->ud, SDEV_EVENT_ERROR_TCP); + return -1; + } + + usbip_dbg_stub_tx("send txdata\n"); + total_size += txsize; + } + + spin_lock_irqsave(&sdev->priv_lock, flags); + + list_for_each_entry_safe(unlink, tmp, &sdev->unlink_free, list) { + list_del(&unlink->list); + kfree(unlink); + } + + spin_unlock_irqrestore(&sdev->priv_lock, flags); + + return total_size; +} + +int stub_tx_loop(void *data) +{ + struct usbip_device *ud = data; + struct stub_device *sdev = container_of(ud, struct stub_device, ud); + + while (!kthread_should_stop()) { + if (usbip_event_happened(ud)) + break; + + /* + * send_ret_submit comes earlier than send_ret_unlink. stub_rx + * looks at only priv_init queue. If the completion of a URB is + * earlier than the receive of CMD_UNLINK, priv is moved to + * priv_tx queue and stub_rx does not find the target priv. In + * this case, vhci_rx receives the result of the submit request + * and then receives the result of the unlink request. The + * result of the submit is given back to the usbcore as the + * completion of the unlink request. The request of the + * unlink is ignored. This is ok because a driver who calls + * usb_unlink_urb() understands the unlink was too late by + * getting the status of the given-backed URB which has the + * status of usb_submit_urb(). + */ + if (stub_send_ret_submit(sdev) < 0) + break; + + if (stub_send_ret_unlink(sdev) < 0) + break; + + wait_event_interruptible(sdev->tx_waitq, + (!list_empty(&sdev->priv_tx) || + !list_empty(&sdev->unlink_tx) || + kthread_should_stop())); + } + + return 0; +} |