Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'for-linus-4.10-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fix from Juergen Gross:
"A fix for Xen running in nested virtualization environment"
* tag 'for-linus-4.10-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
partially revert "xen: Remove event channel notification through Xen PCI platform device"
+71
+71
drivers/xen/platform-pci.c
+71
drivers/xen/platform-pci.c
···
42
42
static unsigned long platform_mmio;
43
43
static unsigned long platform_mmio_alloc;
44
44
static unsigned long platform_mmiolen;
45
+
static uint64_t callback_via;
45
46
46
47
static unsigned long alloc_xen_mmio(unsigned long len)
47
48
{
···
53
52
BUG_ON(platform_mmio_alloc > platform_mmiolen);
54
53
55
54
return addr;
55
+
}
56
+
57
+
static uint64_t get_callback_via(struct pci_dev *pdev)
58
+
{
59
+
u8 pin;
60
+
int irq;
61
+
62
+
irq = pdev->irq;
63
+
if (irq < 16)
64
+
return irq; /* ISA IRQ */
65
+
66
+
pin = pdev->pin;
67
+
68
+
/* We don't know the GSI. Specify the PCI INTx line instead. */
69
+
return ((uint64_t)0x01 << HVM_CALLBACK_VIA_TYPE_SHIFT) | /* PCI INTx identifier */
70
+
((uint64_t)pci_domain_nr(pdev->bus) << 32) |
71
+
((uint64_t)pdev->bus->number << 16) |
72
+
((uint64_t)(pdev->devfn & 0xff) << 8) |
73
+
((uint64_t)(pin - 1) & 3);
74
+
}
75
+
76
+
static irqreturn_t do_hvm_evtchn_intr(int irq, void *dev_id)
77
+
{
78
+
xen_hvm_evtchn_do_upcall();
79
+
return IRQ_HANDLED;
80
+
}
81
+
82
+
static int xen_allocate_irq(struct pci_dev *pdev)
83
+
{
84
+
return request_irq(pdev->irq, do_hvm_evtchn_intr,
85
+
IRQF_NOBALANCING | IRQF_TRIGGER_RISING,
86
+
"xen-platform-pci", pdev);
87
+
}
88
+
89
+
static int platform_pci_resume(struct pci_dev *pdev)
90
+
{
91
+
int err;
92
+
if (!xen_pv_domain())
93
+
return 0;
94
+
err = xen_set_callback_via(callback_via);
95
+
if (err) {
96
+
dev_err(&pdev->dev, "platform_pci_resume failure!\n");
97
+
return err;
98
+
}
99
+
return 0;
56
100
}
57
101
58
102
static int platform_pci_probe(struct pci_dev *pdev,
···
138
92
platform_mmio = mmio_addr;
139
93
platform_mmiolen = mmio_len;
140
94
95
+
/*
96
+
* Xen HVM guests always use the vector callback mechanism.
97
+
* L1 Dom0 in a nested Xen environment is a PV guest inside in an
98
+
* HVM environment. It needs the platform-pci driver to get
99
+
* notifications from L0 Xen, but it cannot use the vector callback
100
+
* as it is not exported by L1 Xen.
101
+
*/
102
+
if (xen_pv_domain()) {
103
+
ret = xen_allocate_irq(pdev);
104
+
if (ret) {
105
+
dev_warn(&pdev->dev, "request_irq failed err=%d\n", ret);
106
+
goto out;
107
+
}
108
+
callback_via = get_callback_via(pdev);
109
+
ret = xen_set_callback_via(callback_via);
110
+
if (ret) {
111
+
dev_warn(&pdev->dev, "Unable to set the evtchn callback "
112
+
"err=%d\n", ret);
113
+
goto out;
114
+
}
115
+
}
116
+
141
117
max_nr_gframes = gnttab_max_grant_frames();
142
118
grant_frames = alloc_xen_mmio(PAGE_SIZE * max_nr_gframes);
143
119
ret = gnttab_setup_auto_xlat_frames(grant_frames);
···
191
123
.name = DRV_NAME,
192
124
.probe = platform_pci_probe,
193
125
.id_table = platform_pci_tbl,
126
+
#ifdef CONFIG_PM
127
+
.resume_early = platform_pci_resume,
128
+
#endif
194
129
};
195
130
196
131
builtin_pci_driver(platform_driver);