summaryrefslogtreecommitdiffstats
path: root/drivers/usb/usbip/stub_main.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/usbip/stub_main.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/usbip/stub_main.c')
-rw-r--r--drivers/usb/usbip/stub_main.c430
1 files changed, 430 insertions, 0 deletions
diff --git a/drivers/usb/usbip/stub_main.c b/drivers/usb/usbip/stub_main.c
new file mode 100644
index 000000000..e8c3131a8
--- /dev/null
+++ b/drivers/usb/usbip/stub_main.c
@@ -0,0 +1,430 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2003-2008 Takahiro Hirofuchi
+ */
+
+#include <linux/string.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/scatterlist.h>
+
+#include "usbip_common.h"
+#include "stub.h"
+
+#define DRIVER_AUTHOR "Takahiro Hirofuchi"
+#define DRIVER_DESC "USB/IP Host Driver"
+
+struct kmem_cache *stub_priv_cache;
+
+/*
+ * busid_tables defines matching busids that usbip can grab. A user can change
+ * dynamically what device is locally used and what device is exported to a
+ * remote host.
+ */
+#define MAX_BUSID 16
+static struct bus_id_priv busid_table[MAX_BUSID];
+static DEFINE_SPINLOCK(busid_table_lock);
+
+static void init_busid_table(void)
+{
+ int i;
+
+ /*
+ * This also sets the bus_table[i].status to
+ * STUB_BUSID_OTHER, which is 0.
+ */
+ memset(busid_table, 0, sizeof(busid_table));
+
+ for (i = 0; i < MAX_BUSID; i++)
+ spin_lock_init(&busid_table[i].busid_lock);
+}
+
+/*
+ * Find the index of the busid by name.
+ * Must be called with busid_table_lock held.
+ */
+static int get_busid_idx(const char *busid)
+{
+ int i;
+ int idx = -1;
+
+ for (i = 0; i < MAX_BUSID; i++) {
+ spin_lock(&busid_table[i].busid_lock);
+ if (busid_table[i].name[0])
+ if (!strncmp(busid_table[i].name, busid, BUSID_SIZE)) {
+ idx = i;
+ spin_unlock(&busid_table[i].busid_lock);
+ break;
+ }
+ spin_unlock(&busid_table[i].busid_lock);
+ }
+ return idx;
+}
+
+/* Returns holding busid_lock. Should call put_busid_priv() to unlock */
+struct bus_id_priv *get_busid_priv(const char *busid)
+{
+ int idx;
+ struct bus_id_priv *bid = NULL;
+
+ spin_lock(&busid_table_lock);
+ idx = get_busid_idx(busid);
+ if (idx >= 0) {
+ bid = &(busid_table[idx]);
+ /* get busid_lock before returning */
+ spin_lock(&bid->busid_lock);
+ }
+ spin_unlock(&busid_table_lock);
+
+ return bid;
+}
+
+void put_busid_priv(struct bus_id_priv *bid)
+{
+ if (bid)
+ spin_unlock(&bid->busid_lock);
+}
+
+static int add_match_busid(char *busid)
+{
+ int i;
+ int ret = -1;
+
+ spin_lock(&busid_table_lock);
+ /* already registered? */
+ if (get_busid_idx(busid) >= 0) {
+ ret = 0;
+ goto out;
+ }
+
+ for (i = 0; i < MAX_BUSID; i++) {
+ spin_lock(&busid_table[i].busid_lock);
+ if (!busid_table[i].name[0]) {
+ strscpy(busid_table[i].name, busid, BUSID_SIZE);
+ if ((busid_table[i].status != STUB_BUSID_ALLOC) &&
+ (busid_table[i].status != STUB_BUSID_REMOV))
+ busid_table[i].status = STUB_BUSID_ADDED;
+ ret = 0;
+ spin_unlock(&busid_table[i].busid_lock);
+ break;
+ }
+ spin_unlock(&busid_table[i].busid_lock);
+ }
+
+out:
+ spin_unlock(&busid_table_lock);
+
+ return ret;
+}
+
+int del_match_busid(char *busid)
+{
+ int idx;
+ int ret = -1;
+
+ spin_lock(&busid_table_lock);
+ idx = get_busid_idx(busid);
+ if (idx < 0)
+ goto out;
+
+ /* found */
+ ret = 0;
+
+ spin_lock(&busid_table[idx].busid_lock);
+
+ if (busid_table[idx].status == STUB_BUSID_OTHER)
+ memset(busid_table[idx].name, 0, BUSID_SIZE);
+
+ if ((busid_table[idx].status != STUB_BUSID_OTHER) &&
+ (busid_table[idx].status != STUB_BUSID_ADDED))
+ busid_table[idx].status = STUB_BUSID_REMOV;
+
+ spin_unlock(&busid_table[idx].busid_lock);
+out:
+ spin_unlock(&busid_table_lock);
+
+ return ret;
+}
+
+static ssize_t match_busid_show(struct device_driver *drv, char *buf)
+{
+ int i;
+ char *out = buf;
+
+ spin_lock(&busid_table_lock);
+ for (i = 0; i < MAX_BUSID; i++) {
+ spin_lock(&busid_table[i].busid_lock);
+ if (busid_table[i].name[0])
+ out += sprintf(out, "%s ", busid_table[i].name);
+ spin_unlock(&busid_table[i].busid_lock);
+ }
+ spin_unlock(&busid_table_lock);
+ out += sprintf(out, "\n");
+
+ return out - buf;
+}
+
+static ssize_t match_busid_store(struct device_driver *dev, const char *buf,
+ size_t count)
+{
+ int len;
+ char busid[BUSID_SIZE];
+
+ if (count < 5)
+ return -EINVAL;
+
+ /* busid needs to include \0 termination */
+ len = strlcpy(busid, buf + 4, BUSID_SIZE);
+ if (sizeof(busid) <= len)
+ return -EINVAL;
+
+ if (!strncmp(buf, "add ", 4)) {
+ if (add_match_busid(busid) < 0)
+ return -ENOMEM;
+
+ pr_debug("add busid %s\n", busid);
+ return count;
+ }
+
+ if (!strncmp(buf, "del ", 4)) {
+ if (del_match_busid(busid) < 0)
+ return -ENODEV;
+
+ pr_debug("del busid %s\n", busid);
+ return count;
+ }
+
+ return -EINVAL;
+}
+static DRIVER_ATTR_RW(match_busid);
+
+static int do_rebind(char *busid, struct bus_id_priv *busid_priv)
+{
+ int ret = 0;
+
+ /* device_attach() callers should hold parent lock for USB */
+ if (busid_priv->udev->dev.parent)
+ device_lock(busid_priv->udev->dev.parent);
+ ret = device_attach(&busid_priv->udev->dev);
+ if (busid_priv->udev->dev.parent)
+ device_unlock(busid_priv->udev->dev.parent);
+ if (ret < 0)
+ dev_err(&busid_priv->udev->dev, "rebind failed\n");
+ return ret;
+}
+
+static void stub_device_rebind(void)
+{
+#if IS_MODULE(CONFIG_USBIP_HOST)
+ struct bus_id_priv *busid_priv;
+ int i;
+
+ /* update status to STUB_BUSID_OTHER so probe ignores the device */
+ spin_lock(&busid_table_lock);
+ for (i = 0; i < MAX_BUSID; i++) {
+ if (busid_table[i].name[0] &&
+ busid_table[i].shutdown_busid) {
+ busid_priv = &(busid_table[i]);
+ busid_priv->status = STUB_BUSID_OTHER;
+ }
+ }
+ spin_unlock(&busid_table_lock);
+
+ /* now run rebind - no need to hold locks. driver files are removed */
+ for (i = 0; i < MAX_BUSID; i++) {
+ if (busid_table[i].name[0] &&
+ busid_table[i].shutdown_busid) {
+ busid_priv = &(busid_table[i]);
+ do_rebind(busid_table[i].name, busid_priv);
+ }
+ }
+#endif
+}
+
+static ssize_t rebind_store(struct device_driver *dev, const char *buf,
+ size_t count)
+{
+ int ret;
+ int len;
+ struct bus_id_priv *bid;
+
+ /* buf length should be less that BUSID_SIZE */
+ len = strnlen(buf, BUSID_SIZE);
+
+ if (!(len < BUSID_SIZE))
+ return -EINVAL;
+
+ bid = get_busid_priv(buf);
+ if (!bid)
+ return -ENODEV;
+
+ /* mark the device for deletion so probe ignores it during rescan */
+ bid->status = STUB_BUSID_OTHER;
+ /* release the busid lock */
+ put_busid_priv(bid);
+
+ ret = do_rebind((char *) buf, bid);
+ if (ret < 0)
+ return ret;
+
+ /* delete device from busid_table */
+ del_match_busid((char *) buf);
+
+ return count;
+}
+
+static DRIVER_ATTR_WO(rebind);
+
+static struct stub_priv *stub_priv_pop_from_listhead(struct list_head *listhead)
+{
+ struct stub_priv *priv, *tmp;
+
+ list_for_each_entry_safe(priv, tmp, listhead, list) {
+ list_del_init(&priv->list);
+ return priv;
+ }
+
+ return NULL;
+}
+
+void stub_free_priv_and_urb(struct stub_priv *priv)
+{
+ struct urb *urb;
+ int i;
+
+ for (i = 0; i < priv->num_urbs; i++) {
+ urb = priv->urbs[i];
+
+ if (!urb)
+ return;
+
+ kfree(urb->setup_packet);
+ urb->setup_packet = NULL;
+
+
+ if (urb->transfer_buffer && !priv->sgl) {
+ kfree(urb->transfer_buffer);
+ urb->transfer_buffer = NULL;
+ }
+
+ if (urb->num_sgs) {
+ sgl_free(urb->sg);
+ urb->sg = NULL;
+ urb->num_sgs = 0;
+ }
+
+ usb_free_urb(urb);
+ }
+ if (!list_empty(&priv->list))
+ list_del(&priv->list);
+ if (priv->sgl)
+ sgl_free(priv->sgl);
+ kfree(priv->urbs);
+ kmem_cache_free(stub_priv_cache, priv);
+}
+
+static struct stub_priv *stub_priv_pop(struct stub_device *sdev)
+{
+ unsigned long flags;
+ struct stub_priv *priv;
+
+ spin_lock_irqsave(&sdev->priv_lock, flags);
+
+ priv = stub_priv_pop_from_listhead(&sdev->priv_init);
+ if (priv)
+ goto done;
+
+ priv = stub_priv_pop_from_listhead(&sdev->priv_tx);
+ if (priv)
+ goto done;
+
+ priv = stub_priv_pop_from_listhead(&sdev->priv_free);
+
+done:
+ spin_unlock_irqrestore(&sdev->priv_lock, flags);
+
+ return priv;
+}
+
+void stub_device_cleanup_urbs(struct stub_device *sdev)
+{
+ struct stub_priv *priv;
+ int i;
+
+ dev_dbg(&sdev->udev->dev, "Stub device cleaning up urbs\n");
+
+ while ((priv = stub_priv_pop(sdev))) {
+ for (i = 0; i < priv->num_urbs; i++)
+ usb_kill_urb(priv->urbs[i]);
+
+ stub_free_priv_and_urb(priv);
+ }
+}
+
+static int __init usbip_host_init(void)
+{
+ int ret;
+
+ init_busid_table();
+
+ stub_priv_cache = KMEM_CACHE(stub_priv, SLAB_HWCACHE_ALIGN);
+ if (!stub_priv_cache) {
+ pr_err("kmem_cache_create failed\n");
+ return -ENOMEM;
+ }
+
+ ret = usb_register_device_driver(&stub_driver, THIS_MODULE);
+ if (ret) {
+ pr_err("usb_register failed %d\n", ret);
+ goto err_usb_register;
+ }
+
+ ret = driver_create_file(&stub_driver.drvwrap.driver,
+ &driver_attr_match_busid);
+ if (ret) {
+ pr_err("driver_create_file failed\n");
+ goto err_create_file;
+ }
+
+ ret = driver_create_file(&stub_driver.drvwrap.driver,
+ &driver_attr_rebind);
+ if (ret) {
+ pr_err("driver_create_file failed\n");
+ goto err_create_file;
+ }
+
+ return ret;
+
+err_create_file:
+ usb_deregister_device_driver(&stub_driver);
+err_usb_register:
+ kmem_cache_destroy(stub_priv_cache);
+ return ret;
+}
+
+static void __exit usbip_host_exit(void)
+{
+ driver_remove_file(&stub_driver.drvwrap.driver,
+ &driver_attr_match_busid);
+
+ driver_remove_file(&stub_driver.drvwrap.driver,
+ &driver_attr_rebind);
+
+ /*
+ * deregister() calls stub_disconnect() for all devices. Device
+ * specific data is cleared in stub_disconnect().
+ */
+ usb_deregister_device_driver(&stub_driver);
+
+ /* initiate scan to attach devices */
+ stub_device_rebind();
+
+ kmem_cache_destroy(stub_priv_cache);
+}
+
+module_init(usbip_host_init);
+module_exit(usbip_host_exit);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");