@@ -48,11 +48,25 @@ For server running on QEMU host with virtio transport::
mount -t 9p -o trans=virtio <mount_tag> /mnt/9
-where mount_tag is the tag associated by the server to each of the exported
+where mount_tag is the tag generated by the server to each of the exported
mount points. Each 9P export is seen by the client as a virtio device with an
associated "mount_tag" property. Available mount tags can be
seen by reading /sys/bus/virtio/drivers/9pnet_virtio/virtio<n>/mount_tag files.
+USBG Usage
+==========
+
+To mount a 9p FS on a USB Host accessible via the gadget at runtime::
+
+ mount -t 9p -o trans=usbg,aname=/path/to/fs <device> /mnt/9
+
+To mount a 9p FS on a USB Host accessible via the gadget as root filesystem::
+
+ root=<device> rootfstype=9p rootflags=trans=usbg,cache=loose,uname=root,access=0,dfltuid=0,dfltgid=0,aname=/path/to/rootfs
+
+where <device> is the tag associated by the usb gadget transport.
+It is defined by the configfs instance name.
+
Options
=======
@@ -68,6 +82,7 @@ Options
virtio connect to the next virtio channel available
(from QEMU with trans_virtio module)
rdma connect to a specified RDMA channel
+ usbg connect to a specified usb gadget channel
======== ============================================
uname=name user name to attempt mount as on the remote server. The
@@ -40,6 +40,12 @@ config NET_9P_XEN
This builds support for a transport for 9pfs between
two Xen domains.
+config NET_9P_USBG
+ bool "9P USB Gadget Transport"
+ depends on USB_GADGET
+ help
+ This builds support for a transport for 9pfs over
+ usb gadget.
config NET_9P_RDMA
depends on INET && INFINIBAND && INFINIBAND_ADDR_TRANS
@@ -4,6 +4,7 @@ obj-$(CONFIG_NET_9P_FD) += 9pnet_fd.o
obj-$(CONFIG_NET_9P_XEN) += 9pnet_xen.o
obj-$(CONFIG_NET_9P_VIRTIO) += 9pnet_virtio.o
obj-$(CONFIG_NET_9P_RDMA) += 9pnet_rdma.o
+obj-$(CONFIG_NET_9P_USBG) += 9pnet_usbg.o
9pnet-objs := \
mod.o \
@@ -23,3 +24,6 @@ obj-$(CONFIG_NET_9P_RDMA) += 9pnet_rdma.o
9pnet_rdma-objs := \
trans_rdma.o \
+
+9pnet_usbg-objs := \
+ trans_usbg.o \
new file mode 100644
@@ -0,0 +1,956 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * trans_usbg.c - USB peripheral usb9pfs configuration driver and transport.
+ *
+ * Copyright (C) 2024 Michael Grzeschik <m.grzeschik@pengutronix.de>
+ */
+
+/* Gadget usb9pfs only needs two bulk endpoints, and will use the usb9pfs
+ * transport to mount host exported filesystem via usb gadget.
+ */
+
+/* +--------------------------+ | +--------------------------+
+ * | 9PFS mounting client | | | 9PFS exporting server |
+ * SW | | | | |
+ * | (this:trans_usbg) | | |(e.g. diod or nfs-ganesha)|
+ * +-------------^------------+ | +-------------^------------+
+ * | | |
+ * ------------------|------------------------------------|-------------
+ * | | |
+ * +-------------v------------+ | +-------------v------------+
+ * | | | | |
+ * HW | USB Device Controller <---------> USB Host Controller |
+ * | | | | |
+ * +--------------------------+ | +--------------------------+
+ */
+
+#include <linux/cleanup.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/usb/composite.h>
+#include <linux/usb/func_utils.h>
+
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+
+#define DEFAULT_BUFLEN 16384
+
+struct f_usb9pfs {
+ struct p9_client *client;
+
+ /* 9p request lock for en/dequeue */
+ spinlock_t lock;
+
+ struct usb_request *in_req;
+ struct usb_request *out_req;
+
+ struct usb_ep *in_ep;
+ struct usb_ep *out_ep;
+
+ struct completion send;
+ struct completion received;
+
+ unsigned int buflen;
+
+ struct usb_function function;
+};
+
+static inline struct f_usb9pfs *func_to_usb9pfs(struct usb_function *f)
+{
+ return container_of(f, struct f_usb9pfs, function);
+}
+
+struct f_usb9pfs_opts {
+ struct usb_function_instance func_inst;
+ unsigned int buflen;
+
+ struct f_usb9pfs_dev *dev;
+
+ /* Read/write access to configfs attributes is handled by configfs.
+ *
+ * This is to protect the data from concurrent access by read/write
+ * and create symlink/remove symlink.
+ */
+ struct mutex lock;
+ int refcnt;
+};
+
+struct f_usb9pfs_dev {
+ struct f_usb9pfs *usb9pfs;
+ struct f_usb9pfs_opts *opts;
+ char tag[41];
+ bool inuse;
+
+ struct list_head usb9pfs_instance;
+};
+
+static DEFINE_MUTEX(usb9pfs_lock);
+static struct list_head usbg_instance_list;
+
+static int usb9pfs_queue_tx(struct f_usb9pfs *usb9pfs, struct p9_req_t *p9_tx_req,
+ gfp_t gfp_flags)
+{
+ struct usb_composite_dev *cdev = usb9pfs->function.config->cdev;
+ struct usb_request *req = usb9pfs->in_req;
+ int ret;
+
+ if (!(p9_tx_req->tc.size % usb9pfs->in_ep->maxpacket))
+ req->zero = 1;
+
+ req->buf = p9_tx_req->tc.sdata;
+ req->length = p9_tx_req->tc.size;
+ req->context = p9_tx_req;
+
+ dev_dbg(&cdev->gadget->dev, "%s usb9pfs send --> %d/%d, zero: %d\n",
+ usb9pfs->in_ep->name, req->actual, req->length, req->zero);
+
+ ret = usb_ep_queue(usb9pfs->in_ep, req, gfp_flags);
+ if (ret)
+ req->context = NULL;
+
+ dev_dbg(&cdev->gadget->dev, "tx submit --> %d\n", ret);
+
+ return ret;
+}
+
+static int usb9pfs_queue_rx(struct f_usb9pfs *usb9pfs, struct usb_request *req,
+ gfp_t gfp_flags)
+{
+ struct usb_composite_dev *cdev = usb9pfs->function.config->cdev;
+ int ret;
+
+ ret = usb_ep_queue(usb9pfs->out_ep, req, gfp_flags);
+
+ dev_dbg(&cdev->gadget->dev, "rx submit --> %d\n", ret);
+
+ return ret;
+}
+
+static int usb9pfs_transmit(struct f_usb9pfs *usb9pfs, struct p9_req_t *p9_req)
+{
+ int ret = 0;
+
+ guard(spinlock_irqsave)(&usb9pfs->lock);
+
+ ret = usb9pfs_queue_tx(usb9pfs, p9_req, GFP_ATOMIC);
+ if (ret)
+ return ret;
+
+ list_del(&p9_req->req_list);
+
+ p9_req_get(p9_req);
+
+ return ret;
+}
+
+static void usb9pfs_tx_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct f_usb9pfs *usb9pfs = ep->driver_data;
+ struct usb_composite_dev *cdev = usb9pfs->function.config->cdev;
+ struct p9_req_t *p9_tx_req = req->context;
+ unsigned long flags;
+
+ /* reset zero packages */
+ req->zero = 0;
+
+ if (req->status) {
+ dev_err(&cdev->gadget->dev, "%s usb9pfs complete --> %d, %d/%d\n",
+ ep->name, req->status, req->actual, req->length);
+ return;
+ }
+
+ dev_dbg(&cdev->gadget->dev, "%s usb9pfs complete --> %d, %d/%d\n",
+ ep->name, req->status, req->actual, req->length);
+
+ spin_lock_irqsave(&usb9pfs->lock, flags);
+ WRITE_ONCE(p9_tx_req->status, REQ_STATUS_SENT);
+
+ p9_req_put(usb9pfs->client, p9_tx_req);
+
+ req->context = NULL;
+
+ spin_unlock_irqrestore(&usb9pfs->lock, flags);
+
+ complete(&usb9pfs->send);
+}
+
+static struct p9_req_t *usb9pfs_rx_header(struct f_usb9pfs *usb9pfs, void *buf)
+{
+ struct p9_req_t *p9_rx_req;
+ struct p9_fcall rc;
+ int ret;
+
+ /* start by reading header */
+ rc.sdata = buf;
+ rc.offset = 0;
+ rc.capacity = P9_HDRSZ;
+ rc.size = P9_HDRSZ;
+
+ p9_debug(P9_DEBUG_TRANS, "mux %p got %zu bytes\n", usb9pfs,
+ rc.capacity - rc.offset);
+
+ ret = p9_parse_header(&rc, &rc.size, NULL, NULL, 0);
+ if (ret) {
+ p9_debug(P9_DEBUG_ERROR,
+ "error parsing header: %d\n", ret);
+ return NULL;
+ }
+
+ p9_debug(P9_DEBUG_TRANS,
+ "mux %p pkt: size: %d bytes tag: %d\n",
+ usb9pfs, rc.size, rc.tag);
+
+ p9_rx_req = p9_tag_lookup(usb9pfs->client, rc.tag);
+ if (!p9_rx_req || p9_rx_req->status != REQ_STATUS_SENT) {
+ p9_debug(P9_DEBUG_ERROR, "Unexpected packet tag %d\n", rc.tag);
+ return NULL;
+ }
+
+ if (rc.size > p9_rx_req->rc.capacity) {
+ p9_debug(P9_DEBUG_ERROR,
+ "requested packet size too big: %d for tag %d with capacity %zd\n",
+ rc.size, rc.tag, p9_rx_req->rc.capacity);
+ p9_req_put(usb9pfs->client, p9_rx_req);
+ return NULL;
+ }
+
+ if (!p9_rx_req->rc.sdata) {
+ p9_debug(P9_DEBUG_ERROR,
+ "No recv fcall for tag %d (req %p), disconnecting!\n",
+ rc.tag, p9_rx_req);
+ p9_req_put(usb9pfs->client, p9_rx_req);
+ return NULL;
+ }
+
+ return p9_rx_req;
+}
+
+static void usb9pfs_rx_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct f_usb9pfs *usb9pfs = ep->driver_data;
+ struct usb_composite_dev *cdev = usb9pfs->function.config->cdev;
+ struct p9_req_t *p9_rx_req;
+
+ if (req->status) {
+ dev_err(&cdev->gadget->dev, "%s usb9pfs complete --> %d, %d/%d\n",
+ ep->name, req->status, req->actual, req->length);
+ return;
+ }
+
+ p9_rx_req = usb9pfs_rx_header(usb9pfs, req->buf);
+ if (!p9_rx_req)
+ return;
+
+ memcpy(p9_rx_req->rc.sdata, req->buf, req->actual);
+
+ p9_rx_req->rc.size = req->actual;
+
+ p9_client_cb(usb9pfs->client, p9_rx_req, REQ_STATUS_RCVD);
+ p9_req_put(usb9pfs->client, p9_rx_req);
+
+ complete(&usb9pfs->received);
+}
+
+static void disable_ep(struct usb_composite_dev *cdev, struct usb_ep *ep)
+{
+ int value;
+
+ value = usb_ep_disable(ep);
+ if (value < 0)
+ dev_info(&cdev->gadget->dev,
+ "disable %s --> %d\n", ep->name, value);
+}
+
+static void disable_usb9pfs(struct f_usb9pfs *usb9pfs)
+{
+ struct usb_composite_dev *cdev =
+ usb9pfs->function.config->cdev;
+
+ if (usb9pfs->in_req) {
+ usb_ep_free_request(usb9pfs->in_ep, usb9pfs->in_req);
+ usb9pfs->in_req = NULL;
+ }
+
+ if (usb9pfs->out_req) {
+ usb_ep_free_request(usb9pfs->out_ep, usb9pfs->out_req);
+ usb9pfs->out_req = NULL;
+ }
+
+ disable_ep(cdev, usb9pfs->in_ep);
+ disable_ep(cdev, usb9pfs->out_ep);
+ dev_dbg(&cdev->gadget->dev, "%s disabled\n",
+ usb9pfs->function.name);
+}
+
+static int alloc_requests(struct usb_composite_dev *cdev,
+ struct f_usb9pfs *usb9pfs)
+{
+ int ret;
+
+ usb9pfs->in_req = usb_ep_alloc_request(usb9pfs->in_ep, GFP_ATOMIC);
+ if (!usb9pfs->in_req) {
+ ret = -ENOENT;
+ goto fail;
+ }
+
+ usb9pfs->out_req = alloc_ep_req(usb9pfs->out_ep, usb9pfs->buflen);
+ if (!usb9pfs->out_req) {
+ ret = -ENOENT;
+ goto fail_in;
+ }
+
+ usb9pfs->in_req->complete = usb9pfs_tx_complete;
+ usb9pfs->out_req->complete = usb9pfs_rx_complete;
+
+ /* length will be set in complete routine */
+ usb9pfs->in_req->context = usb9pfs;
+ usb9pfs->out_req->context = usb9pfs;
+
+ return 0;
+
+fail_in:
+ usb_ep_free_request(usb9pfs->in_ep, usb9pfs->in_req);
+fail:
+ return ret;
+}
+
+static int enable_endpoint(struct usb_composite_dev *cdev,
+ struct f_usb9pfs *usb9pfs, struct usb_ep *ep)
+{
+ int ret;
+
+ ret = config_ep_by_speed(cdev->gadget, &usb9pfs->function, ep);
+ if (ret)
+ return ret;
+
+ ret = usb_ep_enable(ep);
+ if (ret < 0)
+ return ret;
+
+ ep->driver_data = usb9pfs;
+
+ return 0;
+}
+
+static int
+enable_usb9pfs(struct usb_composite_dev *cdev, struct f_usb9pfs *usb9pfs)
+{
+ struct p9_client *client;
+ int ret = 0;
+
+ ret = enable_endpoint(cdev, usb9pfs, usb9pfs->in_ep);
+ if (ret)
+ goto out;
+
+ ret = enable_endpoint(cdev, usb9pfs, usb9pfs->out_ep);
+ if (ret)
+ goto disable_in;
+
+ ret = alloc_requests(cdev, usb9pfs);
+ if (ret)
+ goto disable_out;
+
+ client = usb9pfs->client;
+ if (client)
+ client->status = Connected;
+
+ dev_dbg(&cdev->gadget->dev, "%s enabled\n", usb9pfs->function.name);
+ return 0;
+
+disable_out:
+ usb_ep_disable(usb9pfs->out_ep);
+disable_in:
+ usb_ep_disable(usb9pfs->in_ep);
+out:
+ return ret;
+}
+
+static int p9_usbg_create(struct p9_client *client, const char *devname, char *args)
+{
+ struct f_usb9pfs_dev *dev;
+ struct f_usb9pfs *usb9pfs;
+ int ret = -ENOENT;
+ int found = 0;
+
+ if (!devname)
+ return -EINVAL;
+
+ guard(mutex)(&usb9pfs_lock);
+
+ list_for_each_entry(dev, &usbg_instance_list, usb9pfs_instance) {
+ if (!strncmp(devname, dev->tag, strlen(devname))) {
+ if (!dev->inuse) {
+ dev->inuse = true;
+ found = 1;
+ break;
+ }
+ ret = -EBUSY;
+ break;
+ }
+ }
+
+ if (!found) {
+ pr_err("no channels available for device %s\n", devname);
+ return ret;
+ }
+
+ usb9pfs = dev->usb9pfs;
+ if (!usb9pfs)
+ return -EINVAL;
+
+ client->trans = (void *)usb9pfs;
+ if (!usb9pfs->in_req)
+ client->status = Disconnected;
+ else
+ client->status = Connected;
+ usb9pfs->client = client;
+
+ client->trans_mod->maxsize = usb9pfs->buflen;
+
+ complete(&usb9pfs->received);
+
+ return 0;
+}
+
+static void usb9pfs_clear_tx(struct f_usb9pfs *usb9pfs)
+{
+ struct p9_req_t *req;
+
+ guard(spinlock_irqsave)(&usb9pfs->lock);
+
+ req = usb9pfs->in_req->context;
+ if (!req)
+ return;
+
+ if (!req->t_err)
+ req->t_err = -ECONNRESET;
+
+ p9_client_cb(usb9pfs->client, req, REQ_STATUS_ERROR);
+}
+
+static void p9_usbg_close(struct p9_client *client)
+{
+ struct f_usb9pfs *usb9pfs;
+ struct f_usb9pfs_dev *dev;
+ struct f_usb9pfs_opts *opts;
+
+ if (!client)
+ return;
+
+ usb9pfs = client->trans;
+ if (!usb9pfs)
+ return;
+
+ client->status = Disconnected;
+
+ usb9pfs_clear_tx(usb9pfs);
+
+ opts = container_of(usb9pfs->function.fi,
+ struct f_usb9pfs_opts, func_inst);
+
+ dev = opts->dev;
+
+ mutex_lock(&usb9pfs_lock);
+ dev->inuse = false;
+ mutex_unlock(&usb9pfs_lock);
+}
+
+static int p9_usbg_request(struct p9_client *client, struct p9_req_t *p9_req)
+{
+ struct f_usb9pfs *usb9pfs = client->trans;
+ int ret;
+
+ if (client->status != Connected)
+ return -EBUSY;
+
+ ret = wait_for_completion_killable(&usb9pfs->received);
+ if (ret)
+ return ret;
+
+ ret = usb9pfs_transmit(usb9pfs, p9_req);
+ if (ret)
+ return ret;
+
+ ret = wait_for_completion_killable(&usb9pfs->send);
+ if (ret)
+ return ret;
+
+ return usb9pfs_queue_rx(usb9pfs, usb9pfs->out_req, GFP_ATOMIC);
+}
+
+static int p9_usbg_cancel(struct p9_client *client, struct p9_req_t *req)
+{
+ struct f_usb9pfs *usb9pfs = client->trans;
+ int ret = 1;
+
+ p9_debug(P9_DEBUG_TRANS, "client %p req %p\n", client, req);
+
+ guard(spinlock_irqsave)(&usb9pfs->lock);
+
+ if (req->status == REQ_STATUS_UNSENT) {
+ list_del(&req->req_list);
+ WRITE_ONCE(req->status, REQ_STATUS_FLSHD);
+ p9_req_put(client, req);
+ ret = 0;
+ }
+
+ return ret;
+}
+
+static struct p9_trans_module p9_usbg_trans = {
+ .name = "usbg",
+ .create = p9_usbg_create,
+ .close = p9_usbg_close,
+ .request = p9_usbg_request,
+ .cancel = p9_usbg_cancel,
+ .owner = THIS_MODULE,
+};
+
+/*-------------------------------------------------------------------------*/
+
+#define USB_PROTOCOL_9PFS 0x09
+
+static struct usb_interface_descriptor usb9pfs_intf = {
+ .bLength = sizeof(usb9pfs_intf),
+ .bDescriptorType = USB_DT_INTERFACE,
+
+ .bNumEndpoints = 2,
+ .bInterfaceClass = USB_CLASS_VENDOR_SPEC,
+ .bInterfaceSubClass = USB_SUBCLASS_VENDOR_SPEC,
+ .bInterfaceProtocol = USB_PROTOCOL_9PFS,
+
+ /* .iInterface = DYNAMIC */
+};
+
+/* full speed support: */
+
+static struct usb_endpoint_descriptor fs_usb9pfs_source_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_endpoint_descriptor fs_usb9pfs_sink_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bEndpointAddress = USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_descriptor_header *fs_usb9pfs_descs[] = {
+ (struct usb_descriptor_header *)&usb9pfs_intf,
+ (struct usb_descriptor_header *)&fs_usb9pfs_sink_desc,
+ (struct usb_descriptor_header *)&fs_usb9pfs_source_desc,
+ NULL,
+};
+
+/* high speed support: */
+
+static struct usb_endpoint_descriptor hs_usb9pfs_source_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = cpu_to_le16(512),
+};
+
+static struct usb_endpoint_descriptor hs_usb9pfs_sink_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = cpu_to_le16(512),
+};
+
+static struct usb_descriptor_header *hs_usb9pfs_descs[] = {
+ (struct usb_descriptor_header *)&usb9pfs_intf,
+ (struct usb_descriptor_header *)&hs_usb9pfs_source_desc,
+ (struct usb_descriptor_header *)&hs_usb9pfs_sink_desc,
+ NULL,
+};
+
+/* super speed support: */
+
+static struct usb_endpoint_descriptor ss_usb9pfs_source_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = cpu_to_le16(1024),
+};
+
+static struct usb_ss_ep_comp_descriptor ss_usb9pfs_source_comp_desc = {
+ .bLength = USB_DT_SS_EP_COMP_SIZE,
+ .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
+ .bMaxBurst = 0,
+ .bmAttributes = 0,
+ .wBytesPerInterval = 0,
+};
+
+static struct usb_endpoint_descriptor ss_usb9pfs_sink_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = cpu_to_le16(1024),
+};
+
+static struct usb_ss_ep_comp_descriptor ss_usb9pfs_sink_comp_desc = {
+ .bLength = USB_DT_SS_EP_COMP_SIZE,
+ .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
+ .bMaxBurst = 0,
+ .bmAttributes = 0,
+ .wBytesPerInterval = 0,
+};
+
+static struct usb_descriptor_header *ss_usb9pfs_descs[] = {
+ (struct usb_descriptor_header *)&usb9pfs_intf,
+ (struct usb_descriptor_header *)&ss_usb9pfs_source_desc,
+ (struct usb_descriptor_header *)&ss_usb9pfs_source_comp_desc,
+ (struct usb_descriptor_header *)&ss_usb9pfs_sink_desc,
+ (struct usb_descriptor_header *)&ss_usb9pfs_sink_comp_desc,
+ NULL,
+};
+
+/* function-specific strings: */
+static struct usb_string strings_usb9pfs[] = {
+ [0].s = "usb9pfs input to output",
+ { } /* end of list */
+};
+
+static struct usb_gadget_strings stringtab_usb9pfs = {
+ .language = 0x0409, /* en-us */
+ .strings = strings_usb9pfs,
+};
+
+static struct usb_gadget_strings *usb9pfs_strings[] = {
+ &stringtab_usb9pfs,
+ NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int usb9pfs_func_bind(struct usb_configuration *c,
+ struct usb_function *f)
+{
+ struct f_usb9pfs *usb9pfs = func_to_usb9pfs(f);
+ struct f_usb9pfs_opts *opts;
+ struct usb_composite_dev *cdev = c->cdev;
+ int ret;
+ int id;
+
+ /* allocate interface ID(s) */
+ id = usb_interface_id(c, f);
+ if (id < 0)
+ return id;
+ usb9pfs_intf.bInterfaceNumber = id;
+
+ id = usb_string_id(cdev);
+ if (id < 0)
+ return id;
+ strings_usb9pfs[0].id = id;
+ usb9pfs_intf.iInterface = id;
+
+ /* allocate endpoints */
+ usb9pfs->in_ep = usb_ep_autoconfig(cdev->gadget,
+ &fs_usb9pfs_source_desc);
+ if (!usb9pfs->in_ep)
+ goto autoconf_fail;
+
+ usb9pfs->out_ep = usb_ep_autoconfig(cdev->gadget,
+ &fs_usb9pfs_sink_desc);
+ if (!usb9pfs->out_ep)
+ goto autoconf_fail;
+
+ /* support high speed hardware */
+ hs_usb9pfs_source_desc.bEndpointAddress =
+ fs_usb9pfs_source_desc.bEndpointAddress;
+ hs_usb9pfs_sink_desc.bEndpointAddress =
+ fs_usb9pfs_sink_desc.bEndpointAddress;
+
+ /* support super speed hardware */
+ ss_usb9pfs_source_desc.bEndpointAddress =
+ fs_usb9pfs_source_desc.bEndpointAddress;
+ ss_usb9pfs_sink_desc.bEndpointAddress =
+ fs_usb9pfs_sink_desc.bEndpointAddress;
+
+ ret = usb_assign_descriptors(f, fs_usb9pfs_descs, hs_usb9pfs_descs,
+ ss_usb9pfs_descs, ss_usb9pfs_descs);
+ if (ret)
+ return ret;
+
+ opts = container_of(f->fi, struct f_usb9pfs_opts, func_inst);
+ opts->dev->usb9pfs = usb9pfs;
+
+ dev_dbg(&cdev->gadget->dev, "%s speed %s: IN/%s, OUT/%s\n",
+ (gadget_is_superspeed(c->cdev->gadget) ? "super" :
+ (gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full")),
+ f->name, usb9pfs->in_ep->name, usb9pfs->out_ep->name);
+
+ return 0;
+
+autoconf_fail:
+ ERROR(cdev, "%s: can't autoconfigure on %s\n",
+ f->name, cdev->gadget->name);
+ return -ENODEV;
+}
+
+static void usb9pfs_func_unbind(struct usb_configuration *c,
+ struct usb_function *f)
+{
+ struct f_usb9pfs *usb9pfs = func_to_usb9pfs(f);
+
+ disable_usb9pfs(usb9pfs);
+}
+
+static void usb9pfs_free_func(struct usb_function *f)
+{
+ struct f_usb9pfs *usb9pfs = func_to_usb9pfs(f);
+ struct f_usb9pfs_opts *opts;
+
+ kfree(usb9pfs);
+
+ opts = container_of(f->fi, struct f_usb9pfs_opts, func_inst);
+
+ mutex_lock(&opts->lock);
+ opts->refcnt--;
+ mutex_unlock(&opts->lock);
+
+ usb_free_all_descriptors(f);
+}
+
+static int usb9pfs_set_alt(struct usb_function *f,
+ unsigned int intf, unsigned int alt)
+{
+ struct f_usb9pfs *usb9pfs = func_to_usb9pfs(f);
+ struct usb_composite_dev *cdev = f->config->cdev;
+
+ return enable_usb9pfs(cdev, usb9pfs);
+}
+
+static void usb9pfs_disable(struct usb_function *f)
+{
+ struct f_usb9pfs *usb9pfs = func_to_usb9pfs(f);
+
+ usb9pfs_clear_tx(usb9pfs);
+}
+
+static struct usb_function *usb9pfs_alloc(struct usb_function_instance *fi)
+{
+ struct f_usb9pfs_opts *usb9pfs_opts;
+ struct f_usb9pfs *usb9pfs;
+
+ usb9pfs = kzalloc(sizeof(*usb9pfs), GFP_KERNEL);
+ if (!usb9pfs)
+ return ERR_PTR(-ENOMEM);
+
+ spin_lock_init(&usb9pfs->lock);
+
+ init_completion(&usb9pfs->send);
+ init_completion(&usb9pfs->received);
+
+ usb9pfs_opts = container_of(fi, struct f_usb9pfs_opts, func_inst);
+
+ mutex_lock(&usb9pfs_opts->lock);
+ usb9pfs_opts->refcnt++;
+ mutex_unlock(&usb9pfs_opts->lock);
+
+ usb9pfs->buflen = usb9pfs_opts->buflen;
+
+ usb9pfs->function.name = "usb9pfs";
+ usb9pfs->function.bind = usb9pfs_func_bind;
+ usb9pfs->function.unbind = usb9pfs_func_unbind;
+ usb9pfs->function.set_alt = usb9pfs_set_alt;
+ usb9pfs->function.disable = usb9pfs_disable;
+ usb9pfs->function.strings = usb9pfs_strings;
+
+ usb9pfs->function.free_func = usb9pfs_free_func;
+
+ return &usb9pfs->function;
+}
+
+static inline struct f_usb9pfs_opts *to_f_usb9pfs_opts(struct config_item *item)
+{
+ return container_of(to_config_group(item), struct f_usb9pfs_opts,
+ func_inst.group);
+}
+
+static inline struct f_usb9pfs_opts *fi_to_f_usb9pfs_opts(struct usb_function_instance *fi)
+{
+ return container_of(fi, struct f_usb9pfs_opts, func_inst);
+}
+
+static void usb9pfs_attr_release(struct config_item *item)
+{
+ struct f_usb9pfs_opts *usb9pfs_opts = to_f_usb9pfs_opts(item);
+
+ usb_put_function_instance(&usb9pfs_opts->func_inst);
+}
+
+static struct configfs_item_operations usb9pfs_item_ops = {
+ .release = usb9pfs_attr_release,
+};
+
+static ssize_t f_usb9pfs_opts_buflen_show(struct config_item *item, char *page)
+{
+ struct f_usb9pfs_opts *opts = to_f_usb9pfs_opts(item);
+ int ret;
+
+ mutex_lock(&opts->lock);
+ ret = sysfs_emit(page, "%d\n", opts->buflen);
+ mutex_unlock(&opts->lock);
+
+ return ret;
+}
+
+static ssize_t f_usb9pfs_opts_buflen_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct f_usb9pfs_opts *opts = to_f_usb9pfs_opts(item);
+ int ret;
+ u32 num;
+
+ guard(mutex)(&opts->lock);
+
+ if (opts->refcnt)
+ return -EBUSY;
+
+ ret = kstrtou32(page, 0, &num);
+ if (ret)
+ return ret;
+
+ opts->buflen = num;
+
+ return len;
+}
+
+CONFIGFS_ATTR(f_usb9pfs_opts_, buflen);
+
+static struct configfs_attribute *usb9pfs_attrs[] = {
+ &f_usb9pfs_opts_attr_buflen,
+ NULL,
+};
+
+static const struct config_item_type usb9pfs_func_type = {
+ .ct_item_ops = &usb9pfs_item_ops,
+ .ct_attrs = usb9pfs_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+static struct f_usb9pfs_dev *_usb9pfs_do_find_dev(const char *tag)
+{
+ struct f_usb9pfs_dev *usb9pfs_dev;
+
+ if (!tag)
+ return NULL;
+
+ list_for_each_entry(usb9pfs_dev, &usbg_instance_list, usb9pfs_instance) {
+ if (strcmp(usb9pfs_dev->tag, tag) == 0)
+ return usb9pfs_dev;
+ }
+
+ return NULL;
+}
+
+static int usb9pfs_tag_instance(struct f_usb9pfs_dev *dev, const char *tag)
+{
+ struct f_usb9pfs_dev *existing;
+ int ret = 0;
+
+ guard(mutex)(&usb9pfs_lock);
+
+ existing = _usb9pfs_do_find_dev(tag);
+ if (!existing)
+ strscpy(dev->tag, tag, ARRAY_SIZE(dev->tag));
+ else if (existing != dev)
+ ret = -EBUSY;
+
+ return ret;
+}
+
+static int usb9pfs_set_inst_tag(struct usb_function_instance *fi, const char *tag)
+{
+ if (strlen(tag) >= sizeof_field(struct f_usb9pfs_dev, tag))
+ return -ENAMETOOLONG;
+ return usb9pfs_tag_instance(fi_to_f_usb9pfs_opts(fi)->dev, tag);
+}
+
+static void usb9pfs_free_instance(struct usb_function_instance *fi)
+{
+ struct f_usb9pfs_opts *usb9pfs_opts =
+ container_of(fi, struct f_usb9pfs_opts, func_inst);
+ struct f_usb9pfs_dev *dev = usb9pfs_opts->dev;
+
+ mutex_lock(&usb9pfs_lock);
+ list_del(&dev->usb9pfs_instance);
+ mutex_unlock(&usb9pfs_lock);
+
+ kfree(usb9pfs_opts);
+}
+
+static struct usb_function_instance *usb9pfs_alloc_instance(void)
+{
+ struct f_usb9pfs_opts *usb9pfs_opts;
+ struct f_usb9pfs_dev *dev;
+
+ usb9pfs_opts = kzalloc(sizeof(*usb9pfs_opts), GFP_KERNEL);
+ if (!usb9pfs_opts)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&usb9pfs_opts->lock);
+
+ usb9pfs_opts->func_inst.set_inst_name = usb9pfs_set_inst_tag;
+ usb9pfs_opts->func_inst.free_func_inst = usb9pfs_free_instance;
+
+ usb9pfs_opts->buflen = DEFAULT_BUFLEN;
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (IS_ERR(dev)) {
+ kfree(usb9pfs_opts);
+ return ERR_CAST(dev);
+ }
+
+ usb9pfs_opts->dev = dev;
+ dev->opts = usb9pfs_opts;
+
+ config_group_init_type_name(&usb9pfs_opts->func_inst.group, "",
+ &usb9pfs_func_type);
+
+ mutex_lock(&usb9pfs_lock);
+ list_add_tail(&dev->usb9pfs_instance, &usbg_instance_list);
+ mutex_unlock(&usb9pfs_lock);
+
+ return &usb9pfs_opts->func_inst;
+}
+DECLARE_USB_FUNCTION(usb9pfs, usb9pfs_alloc_instance, usb9pfs_alloc);
+
+static int __init usb9pfs_modinit(void)
+{
+ int ret;
+
+ INIT_LIST_HEAD(&usbg_instance_list);
+
+ ret = usb_function_register(&usb9pfsusb_func);
+ if (!ret)
+ v9fs_register_trans(&p9_usbg_trans);
+
+ return ret;
+}
+
+static void __exit usb9pfs_modexit(void)
+{
+ usb_function_unregister(&usb9pfsusb_func);
+ v9fs_unregister_trans(&p9_usbg_trans);
+}
+
+module_init(usb9pfs_modinit);
+module_exit(usb9pfs_modexit);
+
+MODULE_ALIAS_9P("usbg");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("USB gadget 9pfs transport");
+MODULE_AUTHOR("Michael Grzeschik");