1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * PCI Backend Common Data Structures & Function Declarations
4 *
5 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
6 */
7 #ifndef __XEN_PCIBACK_H__
8 #define __XEN_PCIBACK_H__
9
10 #include <linux/pci.h>
11 #include <linux/interrupt.h>
12 #include <xen/xenbus.h>
13 #include <linux/list.h>
14 #include <linux/spinlock.h>
15 #include <linux/workqueue.h>
16 #include <linux/atomic.h>
17 #include <xen/events.h>
18 #include <xen/interface/io/pciif.h>
19
20 #define DRV_NAME "xen-pciback"
21
22 struct pci_dev_entry {
23 struct list_head list;
24 struct pci_dev *dev;
25 };
26
27 #define _PDEVF_op_active (0)
28 #define PDEVF_op_active (1<<(_PDEVF_op_active))
29 #define _PCIB_op_pending (1)
30 #define PCIB_op_pending (1<<(_PCIB_op_pending))
31 #define _EOI_pending (2)
32 #define EOI_pending (1<<(_EOI_pending))
33
34 struct xen_pcibk_device {
35 void *pci_dev_data;
36 struct mutex dev_lock;
37 struct xenbus_device *xdev;
38 struct xenbus_watch be_watch;
39 u8 be_watching;
40 int evtchn_irq;
41 struct xen_pci_sharedinfo *sh_info;
42 unsigned long flags;
43 struct work_struct op_work;
44 struct xen_pci_op op;
45 };
46
47 struct xen_pcibk_dev_data {
48 struct list_head config_fields;
49 struct pci_saved_state *pci_saved_state;
50 unsigned int permissive:1;
51 unsigned int allow_interrupt_control:1;
52 unsigned int warned_on_write:1;
53 unsigned int enable_intx:1;
54 unsigned int isr_on:1; /* Whether the IRQ handler is installed. */
55 unsigned int ack_intr:1; /* .. and ACK-ing */
56 unsigned long handled;
57 unsigned int irq; /* Saved in case device transitions to MSI/MSI-X */
58 char irq_name[]; /* xen-pcibk[000:04:00.0] */
59 };
60
61 /* Used by XenBus and xen_pcibk_ops.c */
62 extern wait_queue_head_t xen_pcibk_aer_wait_queue;
63 /* Used by pcistub.c and conf_space_quirks.c */
64 extern struct list_head xen_pcibk_quirks;
65
66 /* Get/Put PCI Devices that are hidden from the PCI Backend Domain */
67 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
68 int domain, int bus,
69 int slot, int func);
70 void pcistub_put_pci_dev(struct pci_dev *dev);
71
xen_pcibk_pv_support(void)72 static inline bool xen_pcibk_pv_support(void)
73 {
74 return IS_ENABLED(CONFIG_XEN_PCIDEV_BACKEND);
75 }
76
77 /* Ensure a device is turned off or reset */
78 void xen_pcibk_reset_device(struct pci_dev *pdev);
79
80 /* Access a virtual configuration space for a PCI device */
81 int xen_pcibk_config_init(void);
82 int xen_pcibk_config_init_dev(struct pci_dev *dev);
83 void xen_pcibk_config_free_dyn_fields(struct pci_dev *dev);
84 void xen_pcibk_config_reset_dev(struct pci_dev *dev);
85 void xen_pcibk_config_free_dev(struct pci_dev *dev);
86 int xen_pcibk_config_read(struct pci_dev *dev, int offset, int size,
87 u32 *ret_val);
88 int xen_pcibk_config_write(struct pci_dev *dev, int offset, int size,
89 u32 value);
90
91 /* Handle requests for specific devices from the frontend */
92 typedef int (*publish_pci_dev_cb) (struct xen_pcibk_device *pdev,
93 unsigned int domain, unsigned int bus,
94 unsigned int devfn, unsigned int devid);
95 typedef int (*publish_pci_root_cb) (struct xen_pcibk_device *pdev,
96 unsigned int domain, unsigned int bus);
97
98 /* Backend registration for the two types of BDF representation:
99 * vpci - BDFs start at 00
100 * passthrough - BDFs are exactly like in the host.
101 */
102 struct xen_pcibk_backend {
103 const char *name;
104 int (*init)(struct xen_pcibk_device *pdev);
105 void (*free)(struct xen_pcibk_device *pdev);
106 int (*find)(struct pci_dev *pcidev, struct xen_pcibk_device *pdev,
107 unsigned int *domain, unsigned int *bus,
108 unsigned int *devfn);
109 int (*publish)(struct xen_pcibk_device *pdev, publish_pci_root_cb cb);
110 void (*release)(struct xen_pcibk_device *pdev, struct pci_dev *dev,
111 bool lock);
112 int (*add)(struct xen_pcibk_device *pdev, struct pci_dev *dev,
113 int devid, publish_pci_dev_cb publish_cb);
114 struct pci_dev *(*get)(struct xen_pcibk_device *pdev,
115 unsigned int domain, unsigned int bus,
116 unsigned int devfn);
117 };
118
119 extern const struct xen_pcibk_backend xen_pcibk_vpci_backend;
120 extern const struct xen_pcibk_backend xen_pcibk_passthrough_backend;
121 extern const struct xen_pcibk_backend *xen_pcibk_backend;
122
xen_pcibk_add_pci_dev(struct xen_pcibk_device * pdev,struct pci_dev * dev,int devid,publish_pci_dev_cb publish_cb)123 static inline int xen_pcibk_add_pci_dev(struct xen_pcibk_device *pdev,
124 struct pci_dev *dev,
125 int devid,
126 publish_pci_dev_cb publish_cb)
127 {
128 if (xen_pcibk_backend && xen_pcibk_backend->add)
129 return xen_pcibk_backend->add(pdev, dev, devid, publish_cb);
130 return -1;
131 }
132
xen_pcibk_release_pci_dev(struct xen_pcibk_device * pdev,struct pci_dev * dev,bool lock)133 static inline void xen_pcibk_release_pci_dev(struct xen_pcibk_device *pdev,
134 struct pci_dev *dev, bool lock)
135 {
136 if (xen_pcibk_backend && xen_pcibk_backend->release)
137 return xen_pcibk_backend->release(pdev, dev, lock);
138 }
139
140 static inline struct pci_dev *
xen_pcibk_get_pci_dev(struct xen_pcibk_device * pdev,unsigned int domain,unsigned int bus,unsigned int devfn)141 xen_pcibk_get_pci_dev(struct xen_pcibk_device *pdev, unsigned int domain,
142 unsigned int bus, unsigned int devfn)
143 {
144 if (xen_pcibk_backend && xen_pcibk_backend->get)
145 return xen_pcibk_backend->get(pdev, domain, bus, devfn);
146 return NULL;
147 }
148
149 /**
150 * Add for domain0 PCIE-AER handling. Get guest domain/bus/devfn in xen_pcibk
151 * before sending aer request to pcifront, so that guest could identify
152 * device, coopearte with xen_pcibk to finish aer recovery job if device driver
153 * has the capability
154 */
xen_pcibk_get_pcifront_dev(struct pci_dev * pcidev,struct xen_pcibk_device * pdev,unsigned int * domain,unsigned int * bus,unsigned int * devfn)155 static inline int xen_pcibk_get_pcifront_dev(struct pci_dev *pcidev,
156 struct xen_pcibk_device *pdev,
157 unsigned int *domain,
158 unsigned int *bus,
159 unsigned int *devfn)
160 {
161 if (xen_pcibk_backend && xen_pcibk_backend->find)
162 return xen_pcibk_backend->find(pcidev, pdev, domain, bus,
163 devfn);
164 return -1;
165 }
166
xen_pcibk_init_devices(struct xen_pcibk_device * pdev)167 static inline int xen_pcibk_init_devices(struct xen_pcibk_device *pdev)
168 {
169 if (xen_pcibk_backend && xen_pcibk_backend->init)
170 return xen_pcibk_backend->init(pdev);
171 return -1;
172 }
173
xen_pcibk_publish_pci_roots(struct xen_pcibk_device * pdev,publish_pci_root_cb cb)174 static inline int xen_pcibk_publish_pci_roots(struct xen_pcibk_device *pdev,
175 publish_pci_root_cb cb)
176 {
177 if (xen_pcibk_backend && xen_pcibk_backend->publish)
178 return xen_pcibk_backend->publish(pdev, cb);
179 return -1;
180 }
181
xen_pcibk_release_devices(struct xen_pcibk_device * pdev)182 static inline void xen_pcibk_release_devices(struct xen_pcibk_device *pdev)
183 {
184 if (xen_pcibk_backend && xen_pcibk_backend->free)
185 return xen_pcibk_backend->free(pdev);
186 }
187
188 /* Handles events from front-end */
189 irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id);
190 void xen_pcibk_do_op(struct work_struct *data);
191
xen_pcibk_lateeoi(struct xen_pcibk_device * pdev,unsigned int eoi_flag)192 static inline void xen_pcibk_lateeoi(struct xen_pcibk_device *pdev,
193 unsigned int eoi_flag)
194 {
195 if (test_and_clear_bit(_EOI_pending, &pdev->flags))
196 xen_irq_lateeoi(pdev->evtchn_irq, eoi_flag);
197 }
198
199 int xen_pcibk_xenbus_register(void);
200 void xen_pcibk_xenbus_unregister(void);
201 #endif
202