1 /*
2  * PCI Backend Common Data Structures & Function Declarations
3  *
4  *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
5  */
6 #ifndef __XEN_PCIBACK_H__
7 #define __XEN_PCIBACK_H__
8 
9 #include <linux/pci.h>
10 #include <linux/interrupt.h>
11 #include <xen/xenbus.h>
12 #include <linux/list.h>
13 #include <linux/spinlock.h>
14 #include <linux/workqueue.h>
15 #include <linux/atomic.h>
16 #include <xen/interface/io/pciif.h>
17 
18 #define DRV_NAME	"xen-pciback"
19 
20 struct pci_dev_entry {
21 	struct list_head list;
22 	struct pci_dev *dev;
23 };
24 
25 #define _PDEVF_op_active	(0)
26 #define PDEVF_op_active		(1<<(_PDEVF_op_active))
27 #define _PCIB_op_pending	(1)
28 #define PCIB_op_pending		(1<<(_PCIB_op_pending))
29 
30 struct xen_pcibk_device {
31 	void *pci_dev_data;
32 	struct mutex dev_lock;
33 	struct xenbus_device *xdev;
34 	struct xenbus_watch be_watch;
35 	u8 be_watching;
36 	int evtchn_irq;
37 	struct xen_pci_sharedinfo *sh_info;
38 	unsigned long flags;
39 	struct work_struct op_work;
40 };
41 
42 struct xen_pcibk_dev_data {
43 	struct list_head config_fields;
44 	struct pci_saved_state *pci_saved_state;
45 	unsigned int permissive:1;
46 	unsigned int warned_on_write:1;
47 	unsigned int enable_intx:1;
48 	unsigned int isr_on:1; /* Whether the IRQ handler is installed. */
49 	unsigned int ack_intr:1; /* .. and ACK-ing */
50 	unsigned long handled;
51 	unsigned int irq; /* Saved in case device transitions to MSI/MSI-X */
52 	char irq_name[0]; /* xen-pcibk[000:04:00.0] */
53 };
54 
55 /* Used by XenBus and xen_pcibk_ops.c */
56 extern wait_queue_head_t xen_pcibk_aer_wait_queue;
57 extern struct workqueue_struct *xen_pcibk_wq;
58 /* Used by pcistub.c and conf_space_quirks.c */
59 extern struct list_head xen_pcibk_quirks;
60 
61 /* Get/Put PCI Devices that are hidden from the PCI Backend Domain */
62 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
63 					    int domain, int bus,
64 					    int slot, int func);
65 struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
66 				    struct pci_dev *dev);
67 void pcistub_put_pci_dev(struct pci_dev *dev);
68 
69 /* Ensure a device is turned off or reset */
70 void xen_pcibk_reset_device(struct pci_dev *pdev);
71 
72 /* Access a virtual configuration space for a PCI device */
73 int xen_pcibk_config_init(void);
74 int xen_pcibk_config_init_dev(struct pci_dev *dev);
75 void xen_pcibk_config_free_dyn_fields(struct pci_dev *dev);
76 void xen_pcibk_config_reset_dev(struct pci_dev *dev);
77 void xen_pcibk_config_free_dev(struct pci_dev *dev);
78 int xen_pcibk_config_read(struct pci_dev *dev, int offset, int size,
79 			  u32 *ret_val);
80 int xen_pcibk_config_write(struct pci_dev *dev, int offset, int size,
81 			   u32 value);
82 
83 /* Handle requests for specific devices from the frontend */
84 typedef int (*publish_pci_dev_cb) (struct xen_pcibk_device *pdev,
85 				   unsigned int domain, unsigned int bus,
86 				   unsigned int devfn, unsigned int devid);
87 typedef int (*publish_pci_root_cb) (struct xen_pcibk_device *pdev,
88 				    unsigned int domain, unsigned int bus);
89 
90 /* Backend registration for the two types of BDF representation:
91  *  vpci - BDFs start at 00
92  *  passthrough - BDFs are exactly like in the host.
93  */
94 struct xen_pcibk_backend {
95 	const char *name;
96 	int (*init)(struct xen_pcibk_device *pdev);
97 	void (*free)(struct xen_pcibk_device *pdev);
98 	int (*find)(struct pci_dev *pcidev, struct xen_pcibk_device *pdev,
99 		    unsigned int *domain, unsigned int *bus,
100 		    unsigned int *devfn);
101 	int (*publish)(struct xen_pcibk_device *pdev, publish_pci_root_cb cb);
102 	void (*release)(struct xen_pcibk_device *pdev, struct pci_dev *dev);
103 	int (*add)(struct xen_pcibk_device *pdev, struct pci_dev *dev,
104 		   int devid, publish_pci_dev_cb publish_cb);
105 	struct pci_dev *(*get)(struct xen_pcibk_device *pdev,
106 			       unsigned int domain, unsigned int bus,
107 			       unsigned int devfn);
108 };
109 
110 extern const struct xen_pcibk_backend xen_pcibk_vpci_backend;
111 extern const struct xen_pcibk_backend xen_pcibk_passthrough_backend;
112 extern const struct xen_pcibk_backend *xen_pcibk_backend;
113 
xen_pcibk_add_pci_dev(struct xen_pcibk_device * pdev,struct pci_dev * dev,int devid,publish_pci_dev_cb publish_cb)114 static inline int xen_pcibk_add_pci_dev(struct xen_pcibk_device *pdev,
115 					struct pci_dev *dev,
116 					int devid,
117 					publish_pci_dev_cb publish_cb)
118 {
119 	if (xen_pcibk_backend && xen_pcibk_backend->add)
120 		return xen_pcibk_backend->add(pdev, dev, devid, publish_cb);
121 	return -1;
122 }
123 
xen_pcibk_release_pci_dev(struct xen_pcibk_device * pdev,struct pci_dev * dev)124 static inline void xen_pcibk_release_pci_dev(struct xen_pcibk_device *pdev,
125 					     struct pci_dev *dev)
126 {
127 	if (xen_pcibk_backend && xen_pcibk_backend->free)
128 		return xen_pcibk_backend->release(pdev, dev);
129 }
130 
131 static inline struct pci_dev *
xen_pcibk_get_pci_dev(struct xen_pcibk_device * pdev,unsigned int domain,unsigned int bus,unsigned int devfn)132 xen_pcibk_get_pci_dev(struct xen_pcibk_device *pdev, unsigned int domain,
133 		      unsigned int bus, unsigned int devfn)
134 {
135 	if (xen_pcibk_backend && xen_pcibk_backend->get)
136 		return xen_pcibk_backend->get(pdev, domain, bus, devfn);
137 	return NULL;
138 }
139 
140 /**
141 * Add for domain0 PCIE-AER handling. Get guest domain/bus/devfn in xen_pcibk
142 * before sending aer request to pcifront, so that guest could identify
143 * device, coopearte with xen_pcibk to finish aer recovery job if device driver
144 * has the capability
145 */
xen_pcibk_get_pcifront_dev(struct pci_dev * pcidev,struct xen_pcibk_device * pdev,unsigned int * domain,unsigned int * bus,unsigned int * devfn)146 static inline int xen_pcibk_get_pcifront_dev(struct pci_dev *pcidev,
147 					     struct xen_pcibk_device *pdev,
148 					     unsigned int *domain,
149 					     unsigned int *bus,
150 					     unsigned int *devfn)
151 {
152 	if (xen_pcibk_backend && xen_pcibk_backend->find)
153 		return xen_pcibk_backend->find(pcidev, pdev, domain, bus,
154 					       devfn);
155 	return -1;
156 }
157 
xen_pcibk_init_devices(struct xen_pcibk_device * pdev)158 static inline int xen_pcibk_init_devices(struct xen_pcibk_device *pdev)
159 {
160 	if (xen_pcibk_backend && xen_pcibk_backend->init)
161 		return xen_pcibk_backend->init(pdev);
162 	return -1;
163 }
164 
xen_pcibk_publish_pci_roots(struct xen_pcibk_device * pdev,publish_pci_root_cb cb)165 static inline int xen_pcibk_publish_pci_roots(struct xen_pcibk_device *pdev,
166 					      publish_pci_root_cb cb)
167 {
168 	if (xen_pcibk_backend && xen_pcibk_backend->publish)
169 		return xen_pcibk_backend->publish(pdev, cb);
170 	return -1;
171 }
172 
xen_pcibk_release_devices(struct xen_pcibk_device * pdev)173 static inline void xen_pcibk_release_devices(struct xen_pcibk_device *pdev)
174 {
175 	if (xen_pcibk_backend && xen_pcibk_backend->free)
176 		return xen_pcibk_backend->free(pdev);
177 }
178 
179 /* Handles events from front-end */
180 irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id);
181 void xen_pcibk_do_op(struct work_struct *data);
182 
183 int xen_pcibk_xenbus_register(void);
184 void xen_pcibk_xenbus_unregister(void);
185 
186 extern int verbose_request;
187 
188 void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev);
189 #endif
190 
191 /* Handles shared IRQs that can to device domain and control domain. */
192 void xen_pcibk_irq_handler(struct pci_dev *dev, int reset);
193