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 	struct xen_pci_op op;
41 };
42 
43 struct xen_pcibk_dev_data {
44 	struct list_head config_fields;
45 	struct pci_saved_state *pci_saved_state;
46 	unsigned int permissive:1;
47 	unsigned int warned_on_write:1;
48 	unsigned int enable_intx:1;
49 	unsigned int isr_on:1; /* Whether the IRQ handler is installed. */
50 	unsigned int ack_intr:1; /* .. and ACK-ing */
51 	unsigned long handled;
52 	unsigned int irq; /* Saved in case device transitions to MSI/MSI-X */
53 	char irq_name[0]; /* xen-pcibk[000:04:00.0] */
54 };
55 
56 /* Used by XenBus and xen_pcibk_ops.c */
57 extern wait_queue_head_t xen_pcibk_aer_wait_queue;
58 extern struct workqueue_struct *xen_pcibk_wq;
59 /* Used by pcistub.c and conf_space_quirks.c */
60 extern struct list_head xen_pcibk_quirks;
61 
62 /* Get/Put PCI Devices that are hidden from the PCI Backend Domain */
63 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
64 					    int domain, int bus,
65 					    int slot, int func);
66 struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
67 				    struct pci_dev *dev);
68 void pcistub_put_pci_dev(struct pci_dev *dev);
69 
70 /* Ensure a device is turned off or reset */
71 void xen_pcibk_reset_device(struct pci_dev *pdev);
72 
73 /* Access a virtual configuration space for a PCI device */
74 int xen_pcibk_config_init(void);
75 int xen_pcibk_config_init_dev(struct pci_dev *dev);
76 void xen_pcibk_config_free_dyn_fields(struct pci_dev *dev);
77 void xen_pcibk_config_reset_dev(struct pci_dev *dev);
78 void xen_pcibk_config_free_dev(struct pci_dev *dev);
79 int xen_pcibk_config_read(struct pci_dev *dev, int offset, int size,
80 			  u32 *ret_val);
81 int xen_pcibk_config_write(struct pci_dev *dev, int offset, int size,
82 			   u32 value);
83 
84 /* Handle requests for specific devices from the frontend */
85 typedef int (*publish_pci_dev_cb) (struct xen_pcibk_device *pdev,
86 				   unsigned int domain, unsigned int bus,
87 				   unsigned int devfn, unsigned int devid);
88 typedef int (*publish_pci_root_cb) (struct xen_pcibk_device *pdev,
89 				    unsigned int domain, unsigned int bus);
90 
91 /* Backend registration for the two types of BDF representation:
92  *  vpci - BDFs start at 00
93  *  passthrough - BDFs are exactly like in the host.
94  */
95 struct xen_pcibk_backend {
96 	const char *name;
97 	int (*init)(struct xen_pcibk_device *pdev);
98 	void (*free)(struct xen_pcibk_device *pdev);
99 	int (*find)(struct pci_dev *pcidev, struct xen_pcibk_device *pdev,
100 		    unsigned int *domain, unsigned int *bus,
101 		    unsigned int *devfn);
102 	int (*publish)(struct xen_pcibk_device *pdev, publish_pci_root_cb cb);
103 	void (*release)(struct xen_pcibk_device *pdev, struct pci_dev *dev,
104                         bool lock);
105 	int (*add)(struct xen_pcibk_device *pdev, struct pci_dev *dev,
106 		   int devid, publish_pci_dev_cb publish_cb);
107 	struct pci_dev *(*get)(struct xen_pcibk_device *pdev,
108 			       unsigned int domain, unsigned int bus,
109 			       unsigned int devfn);
110 };
111 
112 extern const struct xen_pcibk_backend xen_pcibk_vpci_backend;
113 extern const struct xen_pcibk_backend xen_pcibk_passthrough_backend;
114 extern const struct xen_pcibk_backend *xen_pcibk_backend;
115 
116 static inline int xen_pcibk_add_pci_dev(struct xen_pcibk_device *pdev,
117 					struct pci_dev *dev,
118 					int devid,
119 					publish_pci_dev_cb publish_cb)
120 {
121 	if (xen_pcibk_backend && xen_pcibk_backend->add)
122 		return xen_pcibk_backend->add(pdev, dev, devid, publish_cb);
123 	return -1;
124 }
125 
126 static inline void xen_pcibk_release_pci_dev(struct xen_pcibk_device *pdev,
127 					     struct pci_dev *dev, bool lock)
128 {
129 	if (xen_pcibk_backend && xen_pcibk_backend->release)
130 		return xen_pcibk_backend->release(pdev, dev, lock);
131 }
132 
133 static inline struct pci_dev *
134 xen_pcibk_get_pci_dev(struct xen_pcibk_device *pdev, unsigned int domain,
135 		      unsigned int bus, unsigned int devfn)
136 {
137 	if (xen_pcibk_backend && xen_pcibk_backend->get)
138 		return xen_pcibk_backend->get(pdev, domain, bus, devfn);
139 	return NULL;
140 }
141 
142 /**
143 * Add for domain0 PCIE-AER handling. Get guest domain/bus/devfn in xen_pcibk
144 * before sending aer request to pcifront, so that guest could identify
145 * device, coopearte with xen_pcibk to finish aer recovery job if device driver
146 * has the capability
147 */
148 static inline int xen_pcibk_get_pcifront_dev(struct pci_dev *pcidev,
149 					     struct xen_pcibk_device *pdev,
150 					     unsigned int *domain,
151 					     unsigned int *bus,
152 					     unsigned int *devfn)
153 {
154 	if (xen_pcibk_backend && xen_pcibk_backend->find)
155 		return xen_pcibk_backend->find(pcidev, pdev, domain, bus,
156 					       devfn);
157 	return -1;
158 }
159 
160 static inline int xen_pcibk_init_devices(struct xen_pcibk_device *pdev)
161 {
162 	if (xen_pcibk_backend && xen_pcibk_backend->init)
163 		return xen_pcibk_backend->init(pdev);
164 	return -1;
165 }
166 
167 static inline int xen_pcibk_publish_pci_roots(struct xen_pcibk_device *pdev,
168 					      publish_pci_root_cb cb)
169 {
170 	if (xen_pcibk_backend && xen_pcibk_backend->publish)
171 		return xen_pcibk_backend->publish(pdev, cb);
172 	return -1;
173 }
174 
175 static inline void xen_pcibk_release_devices(struct xen_pcibk_device *pdev)
176 {
177 	if (xen_pcibk_backend && xen_pcibk_backend->free)
178 		return xen_pcibk_backend->free(pdev);
179 }
180 
181 /* Handles events from front-end */
182 irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id);
183 void xen_pcibk_do_op(struct work_struct *data);
184 
185 int xen_pcibk_xenbus_register(void);
186 void xen_pcibk_xenbus_unregister(void);
187 
188 extern int verbose_request;
189 
190 void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev);
191 #endif
192 
193 /* Handles shared IRQs that can to device domain and control domain. */
194 void xen_pcibk_irq_handler(struct pci_dev *dev, int reset);
195