freebsd-skq/sys/dev/usb/usb_device.h
Hans Petter Selasky b78e84d132 Resolve a special case deadlock: When two or more threads are
simultaneously detaching kernel drivers on the same USB device we can
get stuck in the "usb_wait_pending_ref_locked()" function because the
conditions needed for allowing detach are not met. The "destroy_dev()"
function waits for all system calls involving the given character
device to return. Character device system calls may lock the USB
enumeration lock, which is also held when "destroy_dev()" is
called. This can sometimes lead to a deadlock not noticed by
WITNESS. The current solution is to ensure the calling thread is the
only one holding the USB enumeration lock and prevent other threads
from getting refs while a USB device detach is ongoing. This turned
out not to be sufficient. To solve this deadlock we could use
"destroy_dev_sched()" to schedule the device destruction in the
background, but then we don't know when it is safe to free() the
private data of the character device. Instead a callback function is
executed by the USB explore process to kill off any leftover USB
character devices synchronously after the USB device explore code is
finished and the USB enumeration lock is no longer locked. This makes
porting easier and also ensures us that character devices must
eventually go away after a USB device detach.

While at it ensure that "flag_iserror" is only written when "priv_mtx"
is locked, which is protecting it.

MFC after:	5 days
2015-01-13 16:37:43 +00:00

329 lines
11 KiB
C

/* $FreeBSD$ */
/*-
* Copyright (c) 2008 Hans Petter Selasky. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef _USB_DEVICE_H_
#define _USB_DEVICE_H_
#ifndef USB_GLOBAL_INCLUDE_FILE
#include <dev/usb/usb_core.h>
#include <dev/usb/usb_busdma.h>
#include <dev/usb/usb_transfer.h>
#endif
struct usb_bus_methods;
struct usb_config_descriptor;
struct usb_device; /* linux compat */
struct usb_fs_privdata;
struct usb_hw_ep_profile;
struct usb_symlink; /* UGEN */
#define USB_CTRL_XFER_MAX 2
/* "usb_config_parse()" commands */
#define USB_CFG_ALLOC 0
#define USB_CFG_FREE 1
#define USB_CFG_INIT 2
/* "usb_unconfigure()" flags */
#define USB_UNCFG_FLAG_NONE 0x00
#define USB_UNCFG_FLAG_FREE_EP0 0x02 /* endpoint zero is freed */
struct usb_udev_msg {
struct usb_proc_msg hdr;
struct usb_device *udev;
};
/* The following four structures makes up a tree, where we have the
* leaf structure, "usb_host_endpoint", first, and the root structure,
* "usb_device", last. The four structures below mirror the structure
* of the USB descriptors belonging to an USB configuration. Please
* refer to the USB specification for a definition of "endpoints" and
* "interfaces".
*/
struct usb_host_endpoint {
struct usb_endpoint_descriptor desc;
TAILQ_HEAD(, urb) bsd_urb_list;
struct usb_xfer *bsd_xfer[2];
uint8_t *extra; /* Extra descriptors */
usb_frlength_t fbsd_buf_size;
uint16_t extralen;
uint8_t bsd_iface_index;
} __aligned(USB_HOST_ALIGN);
struct usb_host_interface {
struct usb_interface_descriptor desc;
/* the following array has size "desc.bNumEndpoint" */
struct usb_host_endpoint *endpoint;
const char *string; /* iInterface string, if present */
uint8_t *extra; /* Extra descriptors */
uint16_t extralen;
uint8_t bsd_iface_index;
} __aligned(USB_HOST_ALIGN);
/*
* The following structure defines the USB device flags.
*/
struct usb_device_flags {
enum usb_hc_mode usb_mode; /* host or device mode */
uint8_t self_powered:1; /* set if USB device is self powered */
uint8_t no_strings:1; /* set if USB device does not support
* strings */
uint8_t remote_wakeup:1; /* set if remote wakeup is enabled */
uint8_t uq_bus_powered:1; /* set if BUS powered quirk is present */
/*
* NOTE: Although the flags below will reach the same value
* over time, but the instant values may differ, and
* consequently the flags cannot be merged into one!
*/
uint8_t peer_suspended:1; /* set if peer is suspended */
uint8_t self_suspended:1; /* set if self is suspended */
};
/*
* The following structure is used for power-save purposes. The data
* in this structure is protected by the USB BUS lock.
*/
struct usb_power_save {
usb_ticks_t last_xfer_time; /* copy of "ticks" */
usb_size_t type_refs[4]; /* transfer reference count */
usb_size_t read_refs; /* data read references */
usb_size_t write_refs; /* data write references */
};
/*
* The following structure is used when trying to allocate hardware
* endpoints for an USB configuration in USB device side mode.
*/
struct usb_hw_ep_scratch_sub {
const struct usb_hw_ep_profile *pf;
uint16_t max_frame_size;
uint8_t hw_endpoint_out;
uint8_t hw_endpoint_in;
uint8_t needs_ep_type;
uint8_t needs_in:1;
uint8_t needs_out:1;
};
/*
* The following structure is used when trying to allocate hardware
* endpoints for an USB configuration in USB device side mode.
*/
struct usb_hw_ep_scratch {
struct usb_hw_ep_scratch_sub ep[USB_EP_MAX];
struct usb_hw_ep_scratch_sub *ep_max;
struct usb_config_descriptor *cd;
struct usb_device *udev;
const struct usb_bus_methods *methods;
uint8_t bmOutAlloc[(USB_EP_MAX + 15) / 16];
uint8_t bmInAlloc[(USB_EP_MAX + 15) / 16];
};
/*
* The following structure is used when generating USB descriptors
* from USB templates.
*/
struct usb_temp_setup {
void *buf;
usb_size_t size;
enum usb_dev_speed usb_speed;
uint8_t self_powered;
uint8_t bNumEndpoints;
uint8_t bInterfaceNumber;
uint8_t bAlternateSetting;
uint8_t bConfigurationValue;
usb_error_t err;
};
/*
* The scratch area for USB devices. Access to this structure is
* protected by the enumeration SX lock.
*/
union usb_device_scratch {
struct usb_hw_ep_scratch hw_ep_scratch[1];
struct usb_temp_setup temp_setup[1];
struct {
struct usb_xfer dummy;
struct usb_setup_params parm;
} xfer_setup[1];
uint8_t data[255];
};
/*
* The following structure defines an USB device. There exists one of
* these structures for every USB device.
*/
struct usb_device {
/* generic clear stall message */
struct usb_udev_msg cs_msg[2];
struct sx enum_sx;
struct sx sr_sx;
struct mtx device_mtx;
struct cv ctrlreq_cv;
struct cv ref_cv;
#if (USB_HAVE_FIXED_IFACE == 0)
struct usb_interface *ifaces;
#else
struct usb_interface ifaces[USB_IFACE_MAX];
#endif
struct usb_endpoint ctrl_ep; /* Control Endpoint 0 */
#if (USB_HAVE_FIXED_ENDPOINT == 0)
struct usb_endpoint *endpoints;
#else
struct usb_endpoint endpoints[USB_MAX_EP_UNITS];
#endif
struct usb_power_save pwr_save;/* power save data */
struct usb_bus *bus; /* our USB BUS */
device_t parent_dev; /* parent device */
struct usb_device *parent_hub;
struct usb_device *parent_hs_hub; /* high-speed parent HUB */
struct usb_config_descriptor *cdesc; /* full config descr */
struct usb_hub *hub; /* only if this is a hub */
struct usb_xfer *ctrl_xfer[USB_CTRL_XFER_MAX];
struct usb_temp_data *usb_template_ptr;
struct usb_endpoint *ep_curr; /* current clear stall endpoint */
#if USB_HAVE_UGEN
struct usb_fifo *fifo[USB_FIFO_MAX];
struct usb_symlink *ugen_symlink; /* our generic symlink */
struct usb_fs_privdata *ctrl_dev; /* Control Endpoint 0 device node */
LIST_HEAD(,usb_fs_privdata) pd_list;
char ugen_name[20]; /* name of ugenX.X device */
#endif
usb_ticks_t plugtime; /* copy of "ticks" */
enum usb_dev_state state;
enum usb_dev_speed speed;
uint16_t refcount;
#define USB_DEV_REF_MAX 0xffff
uint16_t power; /* mA the device uses */
uint16_t langid; /* language for strings */
uint16_t autoQuirk[USB_MAX_AUTO_QUIRK]; /* dynamic quirks */
uint8_t address; /* device addess */
uint8_t device_index; /* device index in "bus->devices" */
uint8_t controller_slot_id; /* controller specific value */
uint8_t next_config_index; /* used by USB_RE_ENUM_SET_CONFIG */
uint8_t curr_config_index; /* current configuration index */
uint8_t curr_config_no; /* current configuration number */
uint8_t depth; /* distance from root HUB */
uint8_t port_index; /* parent HUB port index */
uint8_t port_no; /* parent HUB port number */
uint8_t hs_hub_addr; /* high-speed HUB address */
uint8_t hs_port_no; /* high-speed HUB port number */
uint8_t driver_added_refcount; /* our driver added generation count */
uint8_t power_mode; /* see USB_POWER_XXX */
uint8_t re_enumerate_wait; /* set if re-enum. is in progress */
#define USB_RE_ENUM_DONE 0
#define USB_RE_ENUM_START 1
#define USB_RE_ENUM_PWR_OFF 2
#define USB_RE_ENUM_SET_CONFIG 3
uint8_t ifaces_max; /* number of interfaces present */
uint8_t endpoints_max; /* number of endpoints present */
/* the "flags" field is write-protected by "bus->mtx" */
struct usb_device_flags flags;
struct usb_endpoint_descriptor ctrl_ep_desc; /* for endpoint 0 */
struct usb_endpoint_ss_comp_descriptor ctrl_ep_comp_desc; /* for endpoint 0 */
struct usb_device_descriptor ddesc; /* device descriptor */
char *serial; /* serial number, can be NULL */
char *manufacturer; /* manufacturer string, can be NULL */
char *product; /* product string, can be NULL */
#if USB_HAVE_COMPAT_LINUX
/* Linux compat */
struct usb_device_descriptor descriptor;
struct usb_host_endpoint ep0;
struct usb_interface *linux_iface_start;
struct usb_interface *linux_iface_end;
struct usb_host_endpoint *linux_endpoint_start;
struct usb_host_endpoint *linux_endpoint_end;
uint16_t devnum;
#endif
uint32_t clear_stall_errors; /* number of clear-stall failures */
union usb_device_scratch scratch;
#if (USB_HAVE_FIXED_CONFIG != 0)
uint32_t config_data[(USB_CONFIG_MAX + 3) / 4];
#endif
};
/* globals */
extern int usb_template;
/* function prototypes */
const char *usb_statestr(enum usb_dev_state state);
struct usb_device *usb_alloc_device(device_t parent_dev, struct usb_bus *bus,
struct usb_device *parent_hub, uint8_t depth,
uint8_t port_index, uint8_t port_no,
enum usb_dev_speed speed, enum usb_hc_mode mode);
#if USB_HAVE_UGEN
struct usb_fs_privdata *usb_make_dev(struct usb_device *, const char *,
int, int, int, uid_t, gid_t, int);
void usb_destroy_dev(struct usb_fs_privdata *);
void usb_destroy_dev_sync(struct usb_fs_privdata *);
#endif
usb_error_t usb_probe_and_attach(struct usb_device *udev,
uint8_t iface_index);
void usb_detach_device(struct usb_device *, uint8_t, uint8_t);
usb_error_t usb_reset_iface_endpoints(struct usb_device *udev,
uint8_t iface_index);
usb_error_t usbd_set_config_index(struct usb_device *udev, uint8_t index);
usb_error_t usbd_set_endpoint_stall(struct usb_device *udev,
struct usb_endpoint *ep, uint8_t do_stall);
usb_error_t usb_suspend_resume(struct usb_device *udev,
uint8_t do_suspend);
void usb_devinfo(struct usb_device *udev, char *dst_ptr, uint16_t dst_len);
void usb_free_device(struct usb_device *, uint8_t);
void usb_linux_free_device(struct usb_device *dev);
uint8_t usb_peer_can_wakeup(struct usb_device *udev);
struct usb_endpoint *usb_endpoint_foreach(struct usb_device *udev, struct usb_endpoint *ep);
void usb_set_device_state(struct usb_device *, enum usb_dev_state);
enum usb_dev_state usb_get_device_state(struct usb_device *);
uint8_t usbd_enum_lock(struct usb_device *);
void usbd_enum_unlock(struct usb_device *);
void usbd_sr_lock(struct usb_device *);
void usbd_sr_unlock(struct usb_device *);
uint8_t usbd_enum_is_locked(struct usb_device *);
#if USB_HAVE_TT_SUPPORT
void uhub_tt_buffer_reset_async_locked(struct usb_device *, struct usb_endpoint *);
#endif
uint8_t uhub_count_active_host_ports(struct usb_device *, enum usb_dev_speed);
#endif /* _USB_DEVICE_H_ */