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 	unsigned int permissive:1;
45 	unsigned int warned_on_write:1;
46 	unsigned int enable_intx:1;
47 	unsigned int isr_on:1; /* Whether the IRQ handler is installed. */
48 	unsigned int ack_intr:1; /* .. and ACK-ing */
49 	unsigned long handled;
50 	unsigned int irq; /* Saved in case device transitions to MSI/MSI-X */
51 	char irq_name[0]; /* xen-pcibk[000:04:00.0] */
52 };
53 
54 /* Used by XenBus and xen_pcibk_ops.c */
55 extern wait_queue_head_t xen_pcibk_aer_wait_queue;
56 extern struct workqueue_struct *xen_pcibk_wq;
57 /* Used by pcistub.c and conf_space_quirks.c */
58 extern struct list_head xen_pcibk_quirks;
59 
60 /* Get/Put PCI Devices that are hidden from the PCI Backend Domain */
61 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
62 					    int domain, int bus,
63 					    int slot, int func);
64 struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
65 				    struct pci_dev *dev);
66 void pcistub_put_pci_dev(struct pci_dev *dev);
67 
68 /* Ensure a device is turned off or reset */
69 void xen_pcibk_reset_device(struct pci_dev *pdev);
70 
71 /* Access a virtual configuration space for a PCI device */
72 int xen_pcibk_config_init(void);
73 int xen_pcibk_config_init_dev(struct pci_dev *dev);
74 void xen_pcibk_config_free_dyn_fields(struct pci_dev *dev);
75 void xen_pcibk_config_reset_dev(struct pci_dev *dev);
76 void xen_pcibk_config_free_dev(struct pci_dev *dev);
77 int xen_pcibk_config_read(struct pci_dev *dev, int offset, int size,
78 			  u32 *ret_val);
79 int xen_pcibk_config_write(struct pci_dev *dev, int offset, int size,
80 			   u32 value);
81 
82 /* Handle requests for specific devices from the frontend */
83 typedef int (*publish_pci_dev_cb) (struct xen_pcibk_device *pdev,
84 				   unsigned int domain, unsigned int bus,
85 				   unsigned int devfn, unsigned int devid);
86 typedef int (*publish_pci_root_cb) (struct xen_pcibk_device *pdev,
87 				    unsigned int domain, unsigned int bus);
88 
89 /* Backend registration for the two types of BDF representation:
90  *  vpci - BDFs start at 00
91  *  passthrough - BDFs are exactly like in the host.
92  */
93 struct xen_pcibk_backend {
94 	const char *name;
95 	int (*init)(struct xen_pcibk_device *pdev);
96 	void (*free)(struct xen_pcibk_device *pdev);
97 	int (*find)(struct pci_dev *pcidev, struct xen_pcibk_device *pdev,
98 		    unsigned int *domain, unsigned int *bus,
99 		    unsigned int *devfn);
100 	int (*publish)(struct xen_pcibk_device *pdev, publish_pci_root_cb cb);
101 	void (*release)(struct xen_pcibk_device *pdev, struct pci_dev *dev);
102 	int (*add)(struct xen_pcibk_device *pdev, struct pci_dev *dev,
103 		   int devid, publish_pci_dev_cb publish_cb);
104 	struct pci_dev *(*get)(struct xen_pcibk_device *pdev,
105 			       unsigned int domain, unsigned int bus,
106 			       unsigned int devfn);
107 };
108 
109 extern const struct xen_pcibk_backend xen_pcibk_vpci_backend;
110 extern const struct xen_pcibk_backend xen_pcibk_passthrough_backend;
111 extern const struct xen_pcibk_backend *xen_pcibk_backend;
112 
113 static inline int xen_pcibk_add_pci_dev(struct xen_pcibk_device *pdev,
114 					struct pci_dev *dev,
115 					int devid,
116 					publish_pci_dev_cb publish_cb)
117 {
118 	if (xen_pcibk_backend && xen_pcibk_backend->add)
119 		return xen_pcibk_backend->add(pdev, dev, devid, publish_cb);
120 	return -1;
121 }
122 
123 static inline void xen_pcibk_release_pci_dev(struct xen_pcibk_device *pdev,
124 					     struct pci_dev *dev)
125 {
126 	if (xen_pcibk_backend && xen_pcibk_backend->free)
127 		return xen_pcibk_backend->release(pdev, dev);
128 }
129 
130 static inline struct pci_dev *
131 xen_pcibk_get_pci_dev(struct xen_pcibk_device *pdev, unsigned int domain,
132 		      unsigned int bus, unsigned int devfn)
133 {
134 	if (xen_pcibk_backend && xen_pcibk_backend->get)
135 		return xen_pcibk_backend->get(pdev, domain, bus, devfn);
136 	return NULL;
137 }
138 
139 /**
140 * Add for domain0 PCIE-AER handling. Get guest domain/bus/devfn in xen_pcibk
141 * before sending aer request to pcifront, so that guest could identify
142 * device, coopearte with xen_pcibk to finish aer recovery job if device driver
143 * has the capability
144 */
145 static inline int xen_pcibk_get_pcifront_dev(struct pci_dev *pcidev,
146 					     struct xen_pcibk_device *pdev,
147 					     unsigned int *domain,
148 					     unsigned int *bus,
149 					     unsigned int *devfn)
150 {
151 	if (xen_pcibk_backend && xen_pcibk_backend->find)
152 		return xen_pcibk_backend->find(pcidev, pdev, domain, bus,
153 					       devfn);
154 	return -1;
155 }
156 
157 static inline int xen_pcibk_init_devices(struct xen_pcibk_device *pdev)
158 {
159 	if (xen_pcibk_backend && xen_pcibk_backend->init)
160 		return xen_pcibk_backend->init(pdev);
161 	return -1;
162 }
163 
164 static inline int xen_pcibk_publish_pci_roots(struct xen_pcibk_device *pdev,
165 					      publish_pci_root_cb cb)
166 {
167 	if (xen_pcibk_backend && xen_pcibk_backend->publish)
168 		return xen_pcibk_backend->publish(pdev, cb);
169 	return -1;
170 }
171 
172 static inline void xen_pcibk_release_devices(struct xen_pcibk_device *pdev)
173 {
174 	if (xen_pcibk_backend && xen_pcibk_backend->free)
175 		return xen_pcibk_backend->free(pdev);
176 }
177 
178 /* Handles events from front-end */
179 irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id);
180 void xen_pcibk_do_op(struct work_struct *data);
181 
182 int xen_pcibk_xenbus_register(void);
183 void xen_pcibk_xenbus_unregister(void);
184 
185 extern int verbose_request;
186 
187 void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev);
188 #endif
189 
190 /* Handles shared IRQs that can to device domain and control domain. */
191 void xen_pcibk_irq_handler(struct pci_dev *dev, int reset);
192