Skip to content
Navigation Menu
Toggle navigation
Sign in
In this repository
All GitHub Enterprise
↵
Jump to
↵
No suggested jump to results
In this repository
All GitHub Enterprise
↵
Jump to
↵
In this organization
All GitHub Enterprise
↵
Jump to
↵
In this repository
All GitHub Enterprise
↵
Jump to
↵
Sign in
Reseting focus
You signed in with another tab or window.
Reload
to refresh your session.
You signed out in another tab or window.
Reload
to refresh your session.
You switched accounts on another tab or window.
Reload
to refresh your session.
Dismiss alert
{{ message }}
mariux64
/
linux
Public
Notifications
You must be signed in to change notification settings
Fork
0
Star
0
Code
Issues
2
Pull requests
0
Actions
Projects
0
Wiki
Security
Insights
Additional navigation options
Code
Issues
Pull requests
Actions
Projects
Wiki
Security
Insights
Files
b11ecb2
Documentation
arch
block
crypto
drivers
accessibility
acpi
amba
android
ata
atm
auxdisplay
base
bcma
block
bluetooth
bus
cdrom
char
clk
clocksource
connector
coresight
cpufreq
cpuidle
crypto
dca
devfreq
dio
dma-buf
dma
edac
eisa
extcon
firewire
firmware
fmc
gpio
gpu
hid
hsi
hv
hwmon
hwspinlock
i2c
ide
idle
iio
infiniband
input
iommu
ipack
irqchip
isdn
leds
lguest
macintosh
mailbox
mcb
md
media
memory
memstick
message
mfd
misc
mmc
mtd
net
nfc
ntb
nubus
of
oprofile
parisc
parport
pci
pcmcia
phy
pinctrl
platform
pnp
power
powercap
pps
ps3
ptp
pwm
rapidio
ras
regulator
remoteproc
reset
rpmsg
rtc
s390
sbus
scsi
sfi
sh
sn
soc
spi
spmi
ssb
staging
target
tc
thermal
thunderbolt
tty
uio
usb
uwb
vfio
vhost
video
virt
virtio
Kconfig
Makefile
config.c
virtio.c
virtio_balloon.c
virtio_mmio.c
virtio_pci_common.c
virtio_pci_common.h
virtio_pci_legacy.c
virtio_ring.c
vlynq
vme
w1
watchdog
xen
zorro
Kconfig
Makefile
firmware
fs
include
init
ipc
kernel
lib
mm
net
samples
scripts
security
sound
tools
usr
virt
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile
README
REPORTING-BUGS
Breadcrumbs
linux
/
drivers
/
virtio
/
virtio_pci_common.c
Blame
Blame
Latest commit
History
History
493 lines (419 loc) · 12.6 KB
Breadcrumbs
linux
/
drivers
/
virtio
/
virtio_pci_common.c
Top
File metadata and controls
Code
Blame
493 lines (419 loc) · 12.6 KB
Raw
/* * Virtio PCI driver - common functionality for all device versions * * This module allows virtio devices to be used over a virtual PCI device. * This can be used with QEMU based VMMs like KVM or Xen. * * Copyright IBM Corp. 2007 * Copyright Red Hat, Inc. 2014 * * Authors: * Anthony Liguori <aliguori@us.ibm.com> * Rusty Russell <rusty@rustcorp.com.au> * Michael S. Tsirkin <mst@redhat.com> * * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. * */ #include "virtio_pci_common.h" /* wait for pending irq handlers */ void vp_synchronize_vectors(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); int i; if (vp_dev->intx_enabled) synchronize_irq(vp_dev->pci_dev->irq); for (i = 0; i < vp_dev->msix_vectors; ++i) synchronize_irq(vp_dev->msix_entries[i].vector); } /* the notify function used when creating a virt queue */ bool vp_notify(struct virtqueue *vq) { /* we write the queue's selector into the notification register to * signal the other end */ iowrite16(vq->index, (void __iomem *)vq->priv); return true; } /* Handle a configuration change: Tell driver if it wants to know. */ static irqreturn_t vp_config_changed(int irq, void *opaque) { struct virtio_pci_device *vp_dev = opaque; virtio_config_changed(&vp_dev->vdev); return IRQ_HANDLED; } /* Notify all virtqueues on an interrupt. */ static irqreturn_t vp_vring_interrupt(int irq, void *opaque) { struct virtio_pci_device *vp_dev = opaque; struct virtio_pci_vq_info *info; irqreturn_t ret = IRQ_NONE; unsigned long flags; spin_lock_irqsave(&vp_dev->lock, flags); list_for_each_entry(info, &vp_dev->virtqueues, node) { if (vring_interrupt(irq, info->vq) == IRQ_HANDLED) ret = IRQ_HANDLED; } spin_unlock_irqrestore(&vp_dev->lock, flags); return ret; } /* A small wrapper to also acknowledge the interrupt when it's handled. * I really need an EIO hook for the vring so I can ack the interrupt once we * know that we'll be handling the IRQ but before we invoke the callback since * the callback may notify the host which results in the host attempting to * raise an interrupt that we would then mask once we acknowledged the * interrupt. */ static irqreturn_t vp_interrupt(int irq, void *opaque) { struct virtio_pci_device *vp_dev = opaque; u8 isr; /* reading the ISR has the effect of also clearing it so it's very * important to save off the value. */ isr = ioread8(vp_dev->isr); /* It's definitely not us if the ISR was not high */ if (!isr) return IRQ_NONE; /* Configuration change? Tell driver if it wants to know. */ if (isr & VIRTIO_PCI_ISR_CONFIG) vp_config_changed(irq, opaque); return vp_vring_interrupt(irq, opaque); } static void vp_free_vectors(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); int i; if (vp_dev->intx_enabled) { free_irq(vp_dev->pci_dev->irq, vp_dev); vp_dev->intx_enabled = 0; } for (i = 0; i < vp_dev->msix_used_vectors; ++i) free_irq(vp_dev->msix_entries[i].vector, vp_dev); for (i = 0; i < vp_dev->msix_vectors; i++) if (vp_dev->msix_affinity_masks[i]) free_cpumask_var(vp_dev->msix_affinity_masks[i]); if (vp_dev->msix_enabled) { /* Disable the vector used for configuration */ vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR); pci_disable_msix(vp_dev->pci_dev); vp_dev->msix_enabled = 0; } vp_dev->msix_vectors = 0; vp_dev->msix_used_vectors = 0; kfree(vp_dev->msix_names); vp_dev->msix_names = NULL; kfree(vp_dev->msix_entries); vp_dev->msix_entries = NULL; kfree(vp_dev->msix_affinity_masks); vp_dev->msix_affinity_masks = NULL; } static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, bool per_vq_vectors) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); const char *name = dev_name(&vp_dev->vdev.dev); unsigned i, v; int err = -ENOMEM; vp_dev->msix_vectors = nvectors; vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries, GFP_KERNEL); if (!vp_dev->msix_entries) goto error; vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names, GFP_KERNEL); if (!vp_dev->msix_names) goto error; vp_dev->msix_affinity_masks = kzalloc(nvectors * sizeof *vp_dev->msix_affinity_masks, GFP_KERNEL); if (!vp_dev->msix_affinity_masks) goto error; for (i = 0; i < nvectors; ++i) if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i], GFP_KERNEL)) goto error; for (i = 0; i < nvectors; ++i) vp_dev->msix_entries[i].entry = i; err = pci_enable_msix_exact(vp_dev->pci_dev, vp_dev->msix_entries, nvectors); if (err) goto error; vp_dev->msix_enabled = 1; /* Set the vector used for configuration */ v = vp_dev->msix_used_vectors; snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, "%s-config", name); err = request_irq(vp_dev->msix_entries[v].vector, vp_config_changed, 0, vp_dev->msix_names[v], vp_dev); if (err) goto error; ++vp_dev->msix_used_vectors; v = vp_dev->config_vector(vp_dev, v); /* Verify we had enough resources to assign the vector */ if (v == VIRTIO_MSI_NO_VECTOR) { err = -EBUSY; goto error; } if (!per_vq_vectors) { /* Shared vector for all VQs */ v = vp_dev->msix_used_vectors; snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, "%s-virtqueues", name); err = request_irq(vp_dev->msix_entries[v].vector, vp_vring_interrupt, 0, vp_dev->msix_names[v], vp_dev); if (err) goto error; ++vp_dev->msix_used_vectors; } return 0; error: vp_free_vectors(vdev); return err; } static int vp_request_intx(struct virtio_device *vdev) { int err; struct virtio_pci_device *vp_dev = to_vp_device(vdev); err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED, dev_name(&vdev->dev), vp_dev); if (!err) vp_dev->intx_enabled = 1; return err; } static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, void (*callback)(struct virtqueue *vq), const char *name, u16 msix_vec) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL); struct virtqueue *vq; unsigned long flags; /* fill out our structure that represents an active queue */ if (!info) return ERR_PTR(-ENOMEM); vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, msix_vec); if (IS_ERR(vq)) goto out_info; info->vq = vq; if (callback) { spin_lock_irqsave(&vp_dev->lock, flags); list_add(&info->node, &vp_dev->virtqueues); spin_unlock_irqrestore(&vp_dev->lock, flags); } else { INIT_LIST_HEAD(&info->node); } vp_dev->vqs[index] = info; return vq; out_info: kfree(info); return vq; } static void vp_del_vq(struct virtqueue *vq) { struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; unsigned long flags; spin_lock_irqsave(&vp_dev->lock, flags); list_del(&info->node); spin_unlock_irqrestore(&vp_dev->lock, flags); vp_dev->del_vq(info); kfree(info); } /* the config->del_vqs() implementation */ void vp_del_vqs(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); struct virtqueue *vq, *n; struct virtio_pci_vq_info *info; list_for_each_entry_safe(vq, n, &vdev->vqs, list) { info = vp_dev->vqs[vq->index]; if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) free_irq(vp_dev->msix_entries[info->msix_vector].vector, vq); vp_del_vq(vq); } vp_dev->per_vq_vectors = false; vp_free_vectors(vdev); kfree(vp_dev->vqs); vp_dev->vqs = NULL; } static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs, struct virtqueue *vqs[], vq_callback_t *callbacks[], const char *names[], bool use_msix, bool per_vq_vectors) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); u16 msix_vec; int i, err, nvectors, allocated_vectors; vp_dev->vqs = kmalloc(nvqs * sizeof *vp_dev->vqs, GFP_KERNEL); if (!vp_dev->vqs) return -ENOMEM; if (!use_msix) { /* Old style: one normal interrupt for change and all vqs. */ err = vp_request_intx(vdev); if (err) goto error_find; } else { if (per_vq_vectors) { /* Best option: one for change interrupt, one per vq. */ nvectors = 1; for (i = 0; i < nvqs; ++i) if (callbacks[i]) ++nvectors; } else { /* Second best: one for change, shared for all vqs. */ nvectors = 2; } err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors); if (err) goto error_find; } vp_dev->per_vq_vectors = per_vq_vectors; allocated_vectors = vp_dev->msix_used_vectors; for (i = 0; i < nvqs; ++i) { if (!names[i]) { vqs[i] = NULL; continue; } else if (!callbacks[i] || !vp_dev->msix_enabled) msix_vec = VIRTIO_MSI_NO_VECTOR; else if (vp_dev->per_vq_vectors) msix_vec = allocated_vectors++; else msix_vec = VP_MSIX_VQ_VECTOR; vqs[i] = vp_setup_vq(vdev, i, callbacks[i], names[i], msix_vec); if (IS_ERR(vqs[i])) { err = PTR_ERR(vqs[i]); goto error_find; } if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR) continue; /* allocate per-vq irq if available and necessary */ snprintf(vp_dev->msix_names[msix_vec], sizeof *vp_dev->msix_names, "%s-%s", dev_name(&vp_dev->vdev.dev), names[i]); err = request_irq(vp_dev->msix_entries[msix_vec].vector, vring_interrupt, 0, vp_dev->msix_names[msix_vec], vqs[i]); if (err) { vp_del_vq(vqs[i]); goto error_find; } } return 0; error_find: vp_del_vqs(vdev); return err; } /* the config->find_vqs() implementation */ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, struct virtqueue *vqs[], vq_callback_t *callbacks[], const char *names[]) { int err; /* Try MSI-X with one vector per queue. */ err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true); if (!err) return 0; /* Fallback: MSI-X with one vector for config, one shared for queues. */ err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, false); if (!err) return 0; /* Finally fall back to regular interrupts. */ return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, false, false); } const char *vp_bus_name(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); return pci_name(vp_dev->pci_dev); } /* Setup the affinity for a virtqueue: * - force the affinity for per vq vector * - OR over all affinities for shared MSI * - ignore the affinity request if we're using INTX */ int vp_set_vq_affinity(struct virtqueue *vq, int cpu) { struct virtio_device *vdev = vq->vdev; struct virtio_pci_device *vp_dev = to_vp_device(vdev); struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; struct cpumask *mask; unsigned int irq; if (!vq->callback) return -EINVAL; if (vp_dev->msix_enabled) { mask = vp_dev->msix_affinity_masks[info->msix_vector]; irq = vp_dev->msix_entries[info->msix_vector].vector; if (cpu == -1) irq_set_affinity_hint(irq, NULL); else { cpumask_set_cpu(cpu, mask); irq_set_affinity_hint(irq, mask); } } return 0; } #ifdef CONFIG_PM_SLEEP static int virtio_pci_freeze(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); int ret; ret = virtio_device_freeze(&vp_dev->vdev); if (!ret) pci_disable_device(pci_dev); return ret; } static int virtio_pci_restore(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); int ret; ret = pci_enable_device(pci_dev); if (ret) return ret; pci_set_master(pci_dev); return virtio_device_restore(&vp_dev->vdev); } static const struct dev_pm_ops virtio_pci_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(virtio_pci_freeze, virtio_pci_restore) }; #endif /* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */ static const struct pci_device_id virtio_pci_id_table[] = { { PCI_DEVICE(0x1af4, PCI_ANY_ID) }, { 0 } }; MODULE_DEVICE_TABLE(pci, virtio_pci_id_table); static int virtio_pci_probe(struct pci_dev *pci_dev, const struct pci_device_id *id) { return virtio_pci_legacy_probe(pci_dev, id); } static void virtio_pci_remove(struct pci_dev *pci_dev) { virtio_pci_legacy_remove(pci_dev); } static struct pci_driver virtio_pci_driver = { .name = "virtio-pci", .id_table = virtio_pci_id_table, .probe = virtio_pci_probe, .remove = virtio_pci_remove, #ifdef CONFIG_PM_SLEEP .driver.pm = &virtio_pci_pm_ops, #endif }; module_pci_driver(virtio_pci_driver); MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>"); MODULE_DESCRIPTION("virtio-pci"); MODULE_LICENSE("GPL"); MODULE_VERSION("1");
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
You can’t perform that action at this time.