Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
virtio_pci_modern: allow configuring extended features
The virtio specifications allows for up to 128 bits for the
device features. Soon we are going to use some of the 'extended'
bits features (above 64) for the virtio_net driver.
Extend the virtio pci modern driver to support configuring the full
virtio features range, replacing the unrolled loops reading and
writing the features space with explicit one bounded to the actual
features space size in word and implementing the get_extended_features
callback.
Note that in vp_finalize_features() we only need to cache the lower
64 features bits, to process the transport features.
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
+84
-38
+5
-5
drivers/virtio/virtio_pci_modern.c
+5
-5
drivers/virtio/virtio_pci_modern.c
···
22
22
23
23
#define VIRTIO_AVQ_SGS_MAX 4
24
24
25
-
static u64 vp_get_features(struct virtio_device *vdev)
25
+
static void vp_get_features(struct virtio_device *vdev, u64 *features)
26
26
{
27
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struct virtio_pci_device *vp_dev = to_vp_device(vdev);
28
28
29
-
return vp_modern_get_features(&vp_dev->mdev);
29
+
vp_modern_get_extended_features(&vp_dev->mdev, features);
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}
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32
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static int vp_avq_index(struct virtio_device *vdev, u16 *index, u16 *num)
···
437
437
if (vp_check_common_size(vdev))
438
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return -EINVAL;
439
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440
-
vp_modern_set_features(&vp_dev->mdev, vdev->features);
440
+
vp_modern_set_extended_features(&vp_dev->mdev, vdev->features_array);
441
441
442
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return 0;
443
443
}
···
1234
1234
.find_vqs = vp_modern_find_vqs,
1235
1235
.del_vqs = vp_del_vqs,
1236
1236
.synchronize_cbs = vp_synchronize_vectors,
1237
-
.get_features = vp_get_features,
1237
+
.get_extended_features = vp_get_features,
1238
1238
.finalize_features = vp_finalize_features,
1239
1239
.bus_name = vp_bus_name,
1240
1240
.set_vq_affinity = vp_set_vq_affinity,
···
1254
1254
.find_vqs = vp_modern_find_vqs,
1255
1255
.del_vqs = vp_del_vqs,
1256
1256
.synchronize_cbs = vp_synchronize_vectors,
1257
-
.get_features = vp_get_features,
1257
+
.get_extended_features = vp_get_features,
1258
1258
.finalize_features = vp_finalize_features,
1259
1259
.bus_name = vp_bus_name,
1260
1260
.set_vq_affinity = vp_set_vq_affinity,
+40
-29
drivers/virtio/virtio_pci_modern_dev.c
+40
-29
drivers/virtio/virtio_pci_modern_dev.c
···
388
388
EXPORT_SYMBOL_GPL(vp_modern_remove);
389
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390
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/*
391
-
* vp_modern_get_features - get features from device
391
+
* vp_modern_get_extended_features - get features from device
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* @mdev: the modern virtio-pci device
393
+
* @features: the features array to be filled
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*
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-
* Returns the features read from the device
395
+
* Fill the specified features array with the features read from the device
395
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*/
396
-
u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev)
397
+
void vp_modern_get_extended_features(struct virtio_pci_modern_device *mdev,
398
+
u64 *features)
397
399
{
398
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struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
401
+
int i;
399
402
400
-
u64 features;
403
+
virtio_features_zero(features);
404
+
for (i = 0; i < VIRTIO_FEATURES_WORDS; i++) {
405
+
u64 cur;
401
406
402
-
vp_iowrite32(0, &cfg->device_feature_select);
403
-
features = vp_ioread32(&cfg->device_feature);
404
-
vp_iowrite32(1, &cfg->device_feature_select);
405
-
features |= ((u64)vp_ioread32(&cfg->device_feature) << 32);
406
-
407
-
return features;
407
+
vp_iowrite32(i, &cfg->device_feature_select);
408
+
cur = vp_ioread32(&cfg->device_feature);
409
+
features[i >> 1] |= cur << (32 * (i & 1));
410
+
}
408
411
}
409
-
EXPORT_SYMBOL_GPL(vp_modern_get_features);
412
+
EXPORT_SYMBOL_GPL(vp_modern_get_extended_features);
410
413
411
414
/*
412
415
* vp_modern_get_driver_features - get driver features from device
413
416
* @mdev: the modern virtio-pci device
417
+
* @features: the features array to be filled
414
418
*
415
-
* Returns the driver features read from the device
419
+
* Fill the specified features array with the driver features read from the
420
+
* device
416
421
*/
417
-
u64 vp_modern_get_driver_features(struct virtio_pci_modern_device *mdev)
422
+
void
423
+
vp_modern_get_driver_extended_features(struct virtio_pci_modern_device *mdev,
424
+
u64 *features)
418
425
{
419
426
struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
427
+
int i;
420
428
421
-
u64 features;
429
+
virtio_features_zero(features);
430
+
for (i = 0; i < VIRTIO_FEATURES_WORDS; i++) {
431
+
u64 cur;
422
432
423
-
vp_iowrite32(0, &cfg->guest_feature_select);
424
-
features = vp_ioread32(&cfg->guest_feature);
425
-
vp_iowrite32(1, &cfg->guest_feature_select);
426
-
features |= ((u64)vp_ioread32(&cfg->guest_feature) << 32);
427
-
428
-
return features;
433
+
vp_iowrite32(i, &cfg->guest_feature_select);
434
+
cur = vp_ioread32(&cfg->guest_feature);
435
+
features[i >> 1] |= cur << (32 * (i & 1));
436
+
}
429
437
}
430
-
EXPORT_SYMBOL_GPL(vp_modern_get_driver_features);
438
+
EXPORT_SYMBOL_GPL(vp_modern_get_driver_extended_features);
431
439
432
440
/*
433
-
* vp_modern_set_features - set features to device
441
+
* vp_modern_set_extended_features - set features to device
434
442
* @mdev: the modern virtio-pci device
435
443
* @features: the features set to device
436
444
*/
437
-
void vp_modern_set_features(struct virtio_pci_modern_device *mdev,
438
-
u64 features)
445
+
void vp_modern_set_extended_features(struct virtio_pci_modern_device *mdev,
446
+
const u64 *features)
439
447
{
440
448
struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
449
+
int i;
441
450
442
-
vp_iowrite32(0, &cfg->guest_feature_select);
443
-
vp_iowrite32((u32)features, &cfg->guest_feature);
444
-
vp_iowrite32(1, &cfg->guest_feature_select);
445
-
vp_iowrite32(features >> 32, &cfg->guest_feature);
451
+
for (i = 0; i < VIRTIO_FEATURES_WORDS; i++) {
452
+
u32 cur = features[i >> 1] >> (32 * (i & 1));
453
+
454
+
vp_iowrite32(i, &cfg->guest_feature_select);
455
+
vp_iowrite32(cur, &cfg->guest_feature);
456
+
}
446
457
}
447
-
EXPORT_SYMBOL_GPL(vp_modern_set_features);
458
+
EXPORT_SYMBOL_GPL(vp_modern_set_extended_features);
448
459
449
460
/*
450
461
* vp_modern_generation - get the device genreation
+39
-4
include/linux/virtio_pci_modern.h
+39
-4
include/linux/virtio_pci_modern.h
···
3
3
#define _LINUX_VIRTIO_PCI_MODERN_H
4
4
5
5
#include <linux/pci.h>
6
+
#include <linux/virtio_config.h>
6
7
#include <linux/virtio_pci.h>
7
8
8
9
/**
···
96
95
vp_iowrite32(val >> 32, hi);
97
96
}
98
97
99
-
u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev);
100
-
u64 vp_modern_get_driver_features(struct virtio_pci_modern_device *mdev);
101
-
void vp_modern_set_features(struct virtio_pci_modern_device *mdev,
102
-
u64 features);
98
+
void
99
+
vp_modern_get_driver_extended_features(struct virtio_pci_modern_device *mdev,
100
+
u64 *features);
101
+
void vp_modern_get_extended_features(struct virtio_pci_modern_device *mdev,
102
+
u64 *features);
103
+
void vp_modern_set_extended_features(struct virtio_pci_modern_device *mdev,
104
+
const u64 *features);
105
+
106
+
static inline u64
107
+
vp_modern_get_features(struct virtio_pci_modern_device *mdev)
108
+
{
109
+
u64 features_array[VIRTIO_FEATURES_DWORDS];
110
+
111
+
vp_modern_get_extended_features(mdev, features_array);
112
+
return features_array[0];
113
+
}
114
+
115
+
static inline u64
116
+
vp_modern_get_driver_features(struct virtio_pci_modern_device *mdev)
117
+
{
118
+
u64 features_array[VIRTIO_FEATURES_DWORDS];
119
+
int i;
120
+
121
+
vp_modern_get_driver_extended_features(mdev, features_array);
122
+
for (i = 1; i < VIRTIO_FEATURES_DWORDS; ++i)
123
+
WARN_ON_ONCE(features_array[i]);
124
+
return features_array[0];
125
+
}
126
+
127
+
static inline void
128
+
vp_modern_set_features(struct virtio_pci_modern_device *mdev, u64 features)
129
+
{
130
+
u64 features_array[VIRTIO_FEATURES_DWORDS];
131
+
132
+
virtio_features_from_u64(features_array, features);
133
+
vp_modern_set_extended_features(mdev, features_array);
134
+
}
135
+
103
136
u32 vp_modern_generation(struct virtio_pci_modern_device *mdev);
104
137
u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev);
105
138
void vp_modern_set_status(struct virtio_pci_modern_device *mdev,