mirror of
https://github.com/torvalds/linux.git
synced 2024-11-05 03:21:32 +00:00
e8801a7418
As commit 0a9fd01529
'xen/pciback: Document the entry points for 'pcistub_put_pci_dev''
explained there are four entry points in this function.
Two of them are when the user fiddles in the SysFS to
unbind a device which might be in use by a guest or not.
Both 'unbind' states will cause a deadlock as the the PCI lock has
already been taken, which then pci_device_reset tries to take.
We can simplify this by requiring that all callers of
pcistub_put_pci_dev MUST hold the device lock. And then
we can just call the lockless version of pci_device_reset.
To make it even simpler we will modify xen_pcibk_release_pci_dev
to quality whether it should take a lock or not - as it ends
up calling xen_pcibk_release_pci_dev and needs to hold the lock.
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
194 lines
6.2 KiB
C
194 lines
6.2 KiB
C
/*
|
|
* PCI Backend Common Data Structures & Function Declarations
|
|
*
|
|
* Author: Ryan Wilson <hap9@epoch.ncsc.mil>
|
|
*/
|
|
#ifndef __XEN_PCIBACK_H__
|
|
#define __XEN_PCIBACK_H__
|
|
|
|
#include <linux/pci.h>
|
|
#include <linux/interrupt.h>
|
|
#include <xen/xenbus.h>
|
|
#include <linux/list.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/atomic.h>
|
|
#include <xen/interface/io/pciif.h>
|
|
|
|
#define DRV_NAME "xen-pciback"
|
|
|
|
struct pci_dev_entry {
|
|
struct list_head list;
|
|
struct pci_dev *dev;
|
|
};
|
|
|
|
#define _PDEVF_op_active (0)
|
|
#define PDEVF_op_active (1<<(_PDEVF_op_active))
|
|
#define _PCIB_op_pending (1)
|
|
#define PCIB_op_pending (1<<(_PCIB_op_pending))
|
|
|
|
struct xen_pcibk_device {
|
|
void *pci_dev_data;
|
|
struct mutex dev_lock;
|
|
struct xenbus_device *xdev;
|
|
struct xenbus_watch be_watch;
|
|
u8 be_watching;
|
|
int evtchn_irq;
|
|
struct xen_pci_sharedinfo *sh_info;
|
|
unsigned long flags;
|
|
struct work_struct op_work;
|
|
};
|
|
|
|
struct xen_pcibk_dev_data {
|
|
struct list_head config_fields;
|
|
struct pci_saved_state *pci_saved_state;
|
|
unsigned int permissive:1;
|
|
unsigned int warned_on_write:1;
|
|
unsigned int enable_intx:1;
|
|
unsigned int isr_on:1; /* Whether the IRQ handler is installed. */
|
|
unsigned int ack_intr:1; /* .. and ACK-ing */
|
|
unsigned long handled;
|
|
unsigned int irq; /* Saved in case device transitions to MSI/MSI-X */
|
|
char irq_name[0]; /* xen-pcibk[000:04:00.0] */
|
|
};
|
|
|
|
/* Used by XenBus and xen_pcibk_ops.c */
|
|
extern wait_queue_head_t xen_pcibk_aer_wait_queue;
|
|
extern struct workqueue_struct *xen_pcibk_wq;
|
|
/* Used by pcistub.c and conf_space_quirks.c */
|
|
extern struct list_head xen_pcibk_quirks;
|
|
|
|
/* Get/Put PCI Devices that are hidden from the PCI Backend Domain */
|
|
struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
|
|
int domain, int bus,
|
|
int slot, int func);
|
|
struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
|
|
struct pci_dev *dev);
|
|
void pcistub_put_pci_dev(struct pci_dev *dev);
|
|
|
|
/* Ensure a device is turned off or reset */
|
|
void xen_pcibk_reset_device(struct pci_dev *pdev);
|
|
|
|
/* Access a virtual configuration space for a PCI device */
|
|
int xen_pcibk_config_init(void);
|
|
int xen_pcibk_config_init_dev(struct pci_dev *dev);
|
|
void xen_pcibk_config_free_dyn_fields(struct pci_dev *dev);
|
|
void xen_pcibk_config_reset_dev(struct pci_dev *dev);
|
|
void xen_pcibk_config_free_dev(struct pci_dev *dev);
|
|
int xen_pcibk_config_read(struct pci_dev *dev, int offset, int size,
|
|
u32 *ret_val);
|
|
int xen_pcibk_config_write(struct pci_dev *dev, int offset, int size,
|
|
u32 value);
|
|
|
|
/* Handle requests for specific devices from the frontend */
|
|
typedef int (*publish_pci_dev_cb) (struct xen_pcibk_device *pdev,
|
|
unsigned int domain, unsigned int bus,
|
|
unsigned int devfn, unsigned int devid);
|
|
typedef int (*publish_pci_root_cb) (struct xen_pcibk_device *pdev,
|
|
unsigned int domain, unsigned int bus);
|
|
|
|
/* Backend registration for the two types of BDF representation:
|
|
* vpci - BDFs start at 00
|
|
* passthrough - BDFs are exactly like in the host.
|
|
*/
|
|
struct xen_pcibk_backend {
|
|
const char *name;
|
|
int (*init)(struct xen_pcibk_device *pdev);
|
|
void (*free)(struct xen_pcibk_device *pdev);
|
|
int (*find)(struct pci_dev *pcidev, struct xen_pcibk_device *pdev,
|
|
unsigned int *domain, unsigned int *bus,
|
|
unsigned int *devfn);
|
|
int (*publish)(struct xen_pcibk_device *pdev, publish_pci_root_cb cb);
|
|
void (*release)(struct xen_pcibk_device *pdev, struct pci_dev *dev,
|
|
bool lock);
|
|
int (*add)(struct xen_pcibk_device *pdev, struct pci_dev *dev,
|
|
int devid, publish_pci_dev_cb publish_cb);
|
|
struct pci_dev *(*get)(struct xen_pcibk_device *pdev,
|
|
unsigned int domain, unsigned int bus,
|
|
unsigned int devfn);
|
|
};
|
|
|
|
extern const struct xen_pcibk_backend xen_pcibk_vpci_backend;
|
|
extern const struct xen_pcibk_backend xen_pcibk_passthrough_backend;
|
|
extern const struct xen_pcibk_backend *xen_pcibk_backend;
|
|
|
|
static inline int xen_pcibk_add_pci_dev(struct xen_pcibk_device *pdev,
|
|
struct pci_dev *dev,
|
|
int devid,
|
|
publish_pci_dev_cb publish_cb)
|
|
{
|
|
if (xen_pcibk_backend && xen_pcibk_backend->add)
|
|
return xen_pcibk_backend->add(pdev, dev, devid, publish_cb);
|
|
return -1;
|
|
}
|
|
|
|
static inline void xen_pcibk_release_pci_dev(struct xen_pcibk_device *pdev,
|
|
struct pci_dev *dev, bool lock)
|
|
{
|
|
if (xen_pcibk_backend && xen_pcibk_backend->release)
|
|
return xen_pcibk_backend->release(pdev, dev, lock);
|
|
}
|
|
|
|
static inline struct pci_dev *
|
|
xen_pcibk_get_pci_dev(struct xen_pcibk_device *pdev, unsigned int domain,
|
|
unsigned int bus, unsigned int devfn)
|
|
{
|
|
if (xen_pcibk_backend && xen_pcibk_backend->get)
|
|
return xen_pcibk_backend->get(pdev, domain, bus, devfn);
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* Add for domain0 PCIE-AER handling. Get guest domain/bus/devfn in xen_pcibk
|
|
* before sending aer request to pcifront, so that guest could identify
|
|
* device, coopearte with xen_pcibk to finish aer recovery job if device driver
|
|
* has the capability
|
|
*/
|
|
static inline int xen_pcibk_get_pcifront_dev(struct pci_dev *pcidev,
|
|
struct xen_pcibk_device *pdev,
|
|
unsigned int *domain,
|
|
unsigned int *bus,
|
|
unsigned int *devfn)
|
|
{
|
|
if (xen_pcibk_backend && xen_pcibk_backend->find)
|
|
return xen_pcibk_backend->find(pcidev, pdev, domain, bus,
|
|
devfn);
|
|
return -1;
|
|
}
|
|
|
|
static inline int xen_pcibk_init_devices(struct xen_pcibk_device *pdev)
|
|
{
|
|
if (xen_pcibk_backend && xen_pcibk_backend->init)
|
|
return xen_pcibk_backend->init(pdev);
|
|
return -1;
|
|
}
|
|
|
|
static inline int xen_pcibk_publish_pci_roots(struct xen_pcibk_device *pdev,
|
|
publish_pci_root_cb cb)
|
|
{
|
|
if (xen_pcibk_backend && xen_pcibk_backend->publish)
|
|
return xen_pcibk_backend->publish(pdev, cb);
|
|
return -1;
|
|
}
|
|
|
|
static inline void xen_pcibk_release_devices(struct xen_pcibk_device *pdev)
|
|
{
|
|
if (xen_pcibk_backend && xen_pcibk_backend->free)
|
|
return xen_pcibk_backend->free(pdev);
|
|
}
|
|
|
|
/* Handles events from front-end */
|
|
irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id);
|
|
void xen_pcibk_do_op(struct work_struct *data);
|
|
|
|
int xen_pcibk_xenbus_register(void);
|
|
void xen_pcibk_xenbus_unregister(void);
|
|
|
|
extern int verbose_request;
|
|
|
|
void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev);
|
|
#endif
|
|
|
|
/* Handles shared IRQs that can to device domain and control domain. */
|
|
void xen_pcibk_irq_handler(struct pci_dev *dev, int reset);
|