Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block into for-3.18

This is to receive 0a30288da1ae ("blk-mq, percpu_ref: implement a
kludge for SCSI blk-mq stall during probe") which implements
__percpu_ref_kill_expedited() to work around SCSI blk-mq stall.  The
commit reverted and patches to implement proper fix will be added.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>

1 files changed, 129 insertions, 0 deletions

diff --git a/drivers/usb/usbip/vhci.h b/drivers/usb/usbip/vhci.h
new file mode 100644
index 00000000000..a863a98a91c
--- /dev/null
+++ b/drivers/usb/usbip/vhci.h
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2003-2008 Takahiro Hirofuchi
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#ifndef __USBIP_VHCI_H
+#define __USBIP_VHCI_H
+
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <linux/wait.h>
+
+struct vhci_device {
+	struct usb_device *udev;
+
+	/*
+	 * devid specifies a remote usb device uniquely instead
+	 * of combination of busnum and devnum.
+	 */
+	__u32 devid;
+
+	/* speed of a remote device */
+	enum usb_device_speed speed;
+
+	/* vhci root-hub port to which this device is attached */
+	__u32 rhport;
+
+	struct usbip_device ud;
+
+	/* lock for the below link lists */
+	spinlock_t priv_lock;
+
+	/* vhci_priv is linked to one of them. */
+	struct list_head priv_tx;
+	struct list_head priv_rx;
+
+	/* vhci_unlink is linked to one of them */
+	struct list_head unlink_tx;
+	struct list_head unlink_rx;
+
+	/* vhci_tx thread sleeps for this queue */
+	wait_queue_head_t waitq_tx;
+};
+
+/* urb->hcpriv, use container_of() */
+struct vhci_priv {
+	unsigned long seqnum;
+	struct list_head list;
+
+	struct vhci_device *vdev;
+	struct urb *urb;
+};
+
+struct vhci_unlink {
+	/* seqnum of this request */
+	unsigned long seqnum;
+
+	struct list_head list;
+
+	/* seqnum of the unlink target */
+	unsigned long unlink_seqnum;
+};
+
+/* Number of supported ports. Value has an upperbound of USB_MAXCHILDREN */
+#define VHCI_NPORTS 8
+
+/* for usb_bus.hcpriv */
+struct vhci_hcd {
+	spinlock_t lock;
+
+	u32 port_status[VHCI_NPORTS];
+
+	unsigned resuming:1;
+	unsigned long re_timeout;
+
+	atomic_t seqnum;
+
+	/*
+	 * NOTE:
+	 * wIndex shows the port number and begins from 1.
+	 * But, the index of this array begins from 0.
+	 */
+	struct vhci_device vdev[VHCI_NPORTS];
+};
+
+extern struct vhci_hcd *the_controller;
+extern const struct attribute_group dev_attr_group;
+
+/* vhci_hcd.c */
+void rh_port_connect(int rhport, enum usb_device_speed speed);
+
+/* vhci_rx.c */
+struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev, __u32 seqnum);
+int vhci_rx_loop(void *data);
+
+/* vhci_tx.c */
+int vhci_tx_loop(void *data);
+
+static inline struct vhci_device *port_to_vdev(__u32 port)
+{
+	return &the_controller->vdev[port];
+}
+
+static inline struct vhci_hcd *hcd_to_vhci(struct usb_hcd *hcd)
+{
+	return (struct vhci_hcd *) (hcd->hcd_priv);
+}
+
+static inline struct usb_hcd *vhci_to_hcd(struct vhci_hcd *vhci)
+{
+	return container_of((void *) vhci, struct usb_hcd, hcd_priv);
+}
+
+static inline struct device *vhci_dev(struct vhci_hcd *vhci)
+{
+	return vhci_to_hcd(vhci)->self.controller;
+}
+
+#endif /* __USBIP_VHCI_H */