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virtio: fixes

Browse Source 
Most notably this drops the commits that trip up google cloud
 (turns out, it's any legacy device).
 Plus a kerneldoc patch.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio fixes from Michael Tsirkin:
 "Most notably this drops the commits that trip up google cloud (turns
  out, any legacy device).

  Plus a kerneldoc patch"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio: kerneldocs fixes and enhancements
  virtio: Revert "virtio: find_vqs() add arg sizes"
  virtio_vdpa: Revert "virtio_vdpa: support the arg sizes of find_vqs()"
  virtio_pci: Revert "virtio_pci: support the arg sizes of find_vqs()"
  virtio-mmio: Revert "virtio_mmio: support the arg sizes of find_vqs()"
  virtio: Revert "virtio: add helper virtio_find_vqs_ctx_size()"
  virtio_net: Revert "virtio_net: set the default max ring size by find_vqs()"
This commit is contained in:
Linus Torvalds 2022-08-17 08:58:54 -07:00
commit 274a2eebf8
15 changed files with 59 additions and 121 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/um/drivers/virtio_uml.c
View File

@ -1011,7 +1011,7 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
static int vu_find_vqs(struct virtio_device *vdev, unsigned nvqs,
struct virtqueue *vqs[], vq_callback_t *callbacks[],
const char * const names[], u32 sizes[], const bool *ctx,
const char * const names[], const bool *ctx,
struct irq_affinity *desc)
{
struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev);

42
drivers/net/virtio_net.c
View File

@ -3432,29 +3432,6 @@ static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqu
(unsigned int)GOOD_PACKET_LEN);
}
static void virtnet_config_sizes(struct virtnet_info *vi, u32 *sizes)
{
u32 i, rx_size, tx_size;
if (vi->speed == SPEED_UNKNOWN || vi->speed < SPEED_10000) {
rx_size = 1024;
tx_size = 1024;
} else if (vi->speed < SPEED_40000) {
rx_size = 1024 * 4;
tx_size = 1024 * 4;
} else {
rx_size = 1024 * 8;
tx_size = 1024 * 8;
}
for (i = 0; i < vi->max_queue_pairs; i++) {
sizes[rxq2vq(i)] = rx_size;
sizes[txq2vq(i)] = tx_size;
}
}
static int virtnet_find_vqs(struct virtnet_info *vi)
{
vq_callback_t **callbacks;
@ -3462,7 +3439,6 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
int ret = -ENOMEM;
int i, total_vqs;
const char **names;
u32 *sizes;
bool *ctx;
/* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
@ -3490,15 +3466,10 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
ctx = NULL;
}
sizes = kmalloc_array(total_vqs, sizeof(*sizes), GFP_KERNEL);
if (!sizes)
goto err_sizes;
/* Parameters for control virtqueue, if any */
if (vi->has_cvq) {
callbacks[total_vqs - 1] = NULL;
names[total_vqs - 1] = "control";
sizes[total_vqs - 1] = 64;
}
/* Allocate/initialize parameters for send/receive virtqueues */
@ -3513,10 +3484,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
ctx[rxq2vq(i)] = true;
}
virtnet_config_sizes(vi, sizes);
ret = virtio_find_vqs_ctx_size(vi->vdev, total_vqs, vqs, callbacks,
names, sizes, ctx, NULL);
ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks,
names, ctx, NULL);
if (ret)
goto err_find;
@ -3536,8 +3505,6 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
err_find:
kfree(sizes);
err_sizes:
kfree(ctx);
err_ctx:
kfree(names);
@ -3897,9 +3864,6 @@ static int virtnet_probe(struct virtio_device *vdev)
vi->curr_queue_pairs = num_online_cpus();
vi->max_queue_pairs = max_queue_pairs;
virtnet_init_settings(dev);
virtnet_update_settings(vi);
/* Allocate/initialize the rx/tx queues, and invoke find_vqs */
err = init_vqs(vi);
if (err)
@ -3912,6 +3876,8 @@ static int virtnet_probe(struct virtio_device *vdev)
netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
virtnet_init_settings(dev);
if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
vi->failover = net_failover_create(vi->dev);
if (IS_ERR(vi->failover)) {

1
drivers/platform/mellanox/mlxbf-tmfifo.c
View File

@ -928,7 +928,6 @@ static int mlxbf_tmfifo_virtio_find_vqs(struct virtio_device *vdev,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[],
u32 sizes[],
const bool *ctx,
struct irq_affinity *desc)
{

1
drivers/remoteproc/remoteproc_virtio.c
View File

@ -158,7 +158,6 @@ static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[],
u32 sizes[],
const bool * ctx,
struct irq_affinity *desc)
{

1
drivers/s390/virtio/virtio_ccw.c
View File

@ -637,7 +637,6 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[],
u32 sizes[],
const bool *ctx,
struct irq_affinity *desc)
{

9
drivers/virtio/virtio_mmio.c
View File

@ -360,7 +360,7 @@ static void vm_synchronize_cbs(struct virtio_device *vdev)
static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int index,
void (*callback)(struct virtqueue *vq),
const char *name, u32 size, bool ctx)
const char *name, bool ctx)
{
struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
struct virtio_mmio_vq_info *info;
@ -395,11 +395,8 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int in
goto error_new_virtqueue;
}
if (!size || size > num)
size = num;
/* Create the vring */
vq = vring_create_virtqueue(index, size, VIRTIO_MMIO_VRING_ALIGN, vdev,
vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, vdev,
true, true, ctx, vm_notify, callback, name);
if (!vq) {
err = -ENOMEM;
@ -477,7 +474,6 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[],
u32 sizes[],
const bool *ctx,
struct irq_affinity *desc)
{
@ -503,7 +499,6 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
}
vqs[i] = vm_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
sizes ? sizes[i] : 0,
ctx ? ctx[i] : false);
if (IS_ERR(vqs[i])) {
vm_del_vqs(vdev);

20
drivers/virtio/virtio_pci_common.c
View File

@ -174,7 +174,6 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int index,
void (*callback)(struct virtqueue *vq),
const char *name,
u32 size,
bool ctx,
u16 msix_vec)
{
@ -187,7 +186,7 @@ static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int in
if (!info)
return ERR_PTR(-ENOMEM);
vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, size, ctx,
vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx,
msix_vec);
if (IS_ERR(vq))
goto out_info;
@ -284,7 +283,7 @@ void vp_del_vqs(struct virtio_device *vdev)
static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[], vq_callback_t *callbacks[],
const char * const names[], u32 sizes[], bool per_vq_vectors,
const char * const names[], bool per_vq_vectors,
const bool *ctx,
struct irq_affinity *desc)
{
@ -327,8 +326,8 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs,
else
msix_vec = VP_MSIX_VQ_VECTOR;
vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
sizes ? sizes[i] : 0,
ctx ? ctx[i] : false, msix_vec);
ctx ? ctx[i] : false,
msix_vec);
if (IS_ERR(vqs[i])) {
err = PTR_ERR(vqs[i]);
goto error_find;
@ -358,7 +357,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs,
static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[], vq_callback_t *callbacks[],
const char * const names[], u32 sizes[], const bool *ctx)
const char * const names[], const bool *ctx)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
int i, err, queue_idx = 0;
@ -380,7 +379,6 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,
continue;
}
vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
sizes ? sizes[i] : 0,
ctx ? ctx[i] : false,
VIRTIO_MSI_NO_VECTOR);
if (IS_ERR(vqs[i])) {
@ -398,21 +396,21 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,
/* the config->find_vqs() implementation */
int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[], vq_callback_t *callbacks[],
const char * const names[], u32 sizes[], const bool *ctx,
const char * const names[], const bool *ctx,
struct irq_affinity *desc)
{
int err;
/* Try MSI-X with one vector per queue. */
err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, sizes, true, ctx, desc);
err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, true, ctx, desc);
if (!err)
return 0;
/* Fallback: MSI-X with one vector for config, one shared for queues. */
err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, sizes, false, ctx, desc);
err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, false, ctx, desc);
if (!err)
return 0;
/* Finally fall back to regular interrupts. */
return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names, sizes, ctx);
return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names, ctx);
}
const char *vp_bus_name(struct virtio_device *vdev)

3
drivers/virtio/virtio_pci_common.h
View File

@ -80,7 +80,6 @@ struct virtio_pci_device {
unsigned int idx,
void (*callback)(struct virtqueue *vq),
const char *name,
u32 size,
bool ctx,
u16 msix_vec);
void (*del_vq)(struct virtio_pci_vq_info *info);
@ -111,7 +110,7 @@ void vp_del_vqs(struct virtio_device *vdev);
/* the config->find_vqs() implementation */
int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[], vq_callback_t *callbacks[],
const char * const names[], u32 sizes[], const bool *ctx,
const char * const names[], const bool *ctx,
struct irq_affinity *desc);
const char *vp_bus_name(struct virtio_device *vdev);

6
drivers/virtio/virtio_pci_legacy.c
View File

@ -112,7 +112,6 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
unsigned int index,
void (*callback)(struct virtqueue *vq),
const char *name,
u32 size,
bool ctx,
u16 msix_vec)
{
@ -126,13 +125,10 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
if (!num || vp_legacy_get_queue_enable(&vp_dev->ldev, index))
return ERR_PTR(-ENOENT);
if (!size || size > num)
size = num;
info->msix_vector = msix_vec;
/* create the vring */
vq = vring_create_virtqueue(index, size,
vq = vring_create_virtqueue(index, num,
VIRTIO_PCI_VRING_ALIGN, &vp_dev->vdev,
true, false, ctx,
vp_notify, callback, name);

17
drivers/virtio/virtio_pci_modern.c
View File

@ -293,7 +293,6 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
unsigned int index,
void (*callback)(struct virtqueue *vq),
const char *name,
u32 size,
bool ctx,
u16 msix_vec)
{
@ -311,18 +310,15 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
if (!num || vp_modern_get_queue_enable(mdev, index))
return ERR_PTR(-ENOENT);
if (!size || size > num)
size = num;
if (size & (size - 1)) {
dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", size);
if (num & (num - 1)) {
dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num);
return ERR_PTR(-EINVAL);
}
info->msix_vector = msix_vec;
/* create the vring */
vq = vring_create_virtqueue(index, size,
vq = vring_create_virtqueue(index, num,
SMP_CACHE_BYTES, &vp_dev->vdev,
true, true, ctx,
vp_notify, callback, name);
@ -351,15 +347,12 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[],
u32 sizes[],
const bool *ctx,
const char * const names[], const bool *ctx,
struct irq_affinity *desc)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
struct virtqueue *vq;
int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, sizes, ctx,
desc);
int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc);
if (rc)
return rc;

8
drivers/virtio/virtio_ring.c
View File

@ -2426,6 +2426,14 @@ static inline bool more_used(const struct vring_virtqueue *vq)
return vq->packed_ring ? more_used_packed(vq) : more_used_split(vq);
}
/**
* vring_interrupt - notify a virtqueue on an interrupt
* @irq: the IRQ number (ignored)
* @_vq: the struct virtqueue to notify
*
* Calls the callback function of @_vq to process the virtqueue
* notification.
*/
irqreturn_t vring_interrupt(int irq, void *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);

16
drivers/virtio/virtio_vdpa.c
View File

@ -131,7 +131,7 @@ static irqreturn_t virtio_vdpa_virtqueue_cb(void *private)
static struct virtqueue *
virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
void (*callback)(struct virtqueue *vq),
const char *name, u32 size, bool ctx)
const char *name, bool ctx)
{
struct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev);
struct vdpa_device *vdpa = vd_get_vdpa(vdev);
@ -168,17 +168,14 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
goto error_new_virtqueue;
}
if (!size || size > max_num)
size = max_num;
if (ops->get_vq_num_min)
min_num = ops->get_vq_num_min(vdpa);
may_reduce_num = (size == min_num) ? false : true;
may_reduce_num = (max_num == min_num) ? false : true;
/* Create the vring */
align = ops->get_vq_align(vdpa);
vq = vring_create_virtqueue(index, size, align, vdev,
vq = vring_create_virtqueue(index, max_num, align, vdev,
true, may_reduce_num, ctx,
virtio_vdpa_notify, callback, name);
if (!vq) {
@ -272,7 +269,6 @@ static int virtio_vdpa_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[],
u32 sizes[],
const bool *ctx,
struct irq_affinity *desc)
{
@ -288,9 +284,9 @@ static int virtio_vdpa_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
continue;
}
vqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx++, callbacks[i],
names[i], sizes ? sizes[i] : 0,
ctx ? ctx[i] : false);
vqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx++,
callbacks[i], names[i], ctx ?
ctx[i] : false);
if (IS_ERR(vqs[i])) {
err = PTR_ERR(vqs[i]);
goto err_setup_vq;

6
include/linux/virtio.h
View File

@ -11,7 +11,7 @@
#include <linux/gfp.h>
/**
* virtqueue - a queue to register buffers for sending or receiving.
* struct virtqueue - a queue to register buffers for sending or receiving.
* @list: the chain of virtqueues for this device
* @callback: the function to call when buffers are consumed (can be NULL).
* @name: the name of this virtqueue (mainly for debugging)
@ -97,7 +97,7 @@ int virtqueue_resize(struct virtqueue *vq, u32 num,
void (*recycle)(struct virtqueue *vq, void *buf));
/**
* virtio_device - representation of a device using virtio
* struct virtio_device - representation of a device using virtio
* @index: unique position on the virtio bus
* @failed: saved value for VIRTIO_CONFIG_S_FAILED bit (for restore)
* @config_enabled: configuration change reporting enabled
@ -156,7 +156,7 @@ size_t virtio_max_dma_size(struct virtio_device *vdev);
list_for_each_entry(vq, &vdev->vqs, list)
/**
* virtio_driver - operations for a virtio I/O driver
* struct virtio_driver - operations for a virtio I/O driver
* @driver: underlying device driver (populate name and owner).
* @id_table: the ids serviced by this driver.
* @feature_table: an array of feature numbers supported by this driver.

32
include/linux/virtio_config.h
View File

@ -55,7 +55,6 @@ struct virtio_shm_region {
* include a NULL entry for vqs that do not need a callback
* names: array of virtqueue names (mainly for debugging)
* include a NULL entry for vqs unused by driver
* sizes: array of virtqueue sizes
* Returns 0 on success or error status
* @del_vqs: free virtqueues found by find_vqs().
* @synchronize_cbs: synchronize with the virtqueue callbacks (optional)
@ -104,9 +103,7 @@ struct virtio_config_ops {
void (*reset)(struct virtio_device *vdev);
int (*find_vqs)(struct virtio_device *, unsigned nvqs,
struct virtqueue *vqs[], vq_callback_t *callbacks[],
const char * const names[],
u32 sizes[],
const bool *ctx,
const char * const names[], const bool *ctx,
struct irq_affinity *desc);
void (*del_vqs)(struct virtio_device *);
void (*synchronize_cbs)(struct virtio_device *);
@ -215,7 +212,7 @@ struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev,
const char *names[] = { n };
struct virtqueue *vq;
int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names, NULL,
NULL, NULL);
NULL);
if (err < 0)
return ERR_PTR(err);
return vq;
@ -227,8 +224,7 @@ int virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs,
const char * const names[],
struct irq_affinity *desc)
{
return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL,
NULL, desc);
return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL, desc);
}
static inline
@ -237,25 +233,13 @@ int virtio_find_vqs_ctx(struct virtio_device *vdev, unsigned nvqs,
const char * const names[], const bool *ctx,
struct irq_affinity *desc)
{
return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL,
ctx, desc);
}
static inline
int virtio_find_vqs_ctx_size(struct virtio_device *vdev, u32 nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[],
u32 sizes[],
const bool *ctx, struct irq_affinity *desc)
{
return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, sizes,
ctx, desc);
return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, ctx,
desc);
}
/**
* virtio_synchronize_cbs - synchronize with virtqueue callbacks
* @vdev: the device
* @dev: the virtio device
*/
static inline
void virtio_synchronize_cbs(struct virtio_device *dev)
@ -274,7 +258,7 @@ void virtio_synchronize_cbs(struct virtio_device *dev)
/**
* virtio_device_ready - enable vq use in probe function
* @vdev: the device
* @dev: the virtio device
*
* Driver must call this to use vqs in the probe function.
*
@ -322,7 +306,7 @@ const char *virtio_bus_name(struct virtio_device *vdev)
/**
* virtqueue_set_affinity - setting affinity for a virtqueue
* @vq: the virtqueue
* @cpu: the cpu no.
* @cpu_mask: the cpu mask
*
* Pay attention the function are best-effort: the affinity hint may not be set
* due to config support, irq type and sharing.

16
include/uapi/linux/virtio_ring.h
View File

@ -93,15 +93,21 @@
#define VRING_USED_ALIGN_SIZE 4
#define VRING_DESC_ALIGN_SIZE 16
/* Virtio ring descriptors: 16 bytes. These can chain together via "next". */
/**
* struct vring_desc - Virtio ring descriptors,
* 16 bytes long. These can chain together via @next.
*
* @addr: buffer address (guest-physical)
* @len: buffer length
* @flags: descriptor flags
* @next: index of the next descriptor in the chain,
* if the VRING_DESC_F_NEXT flag is set. We chain unused
* descriptors via this, too.
*/
struct vring_desc {
/* Address (guest-physical). */
__virtio64 addr;
/* Length. */
__virtio32 len;
/* The flags as indicated above. */
__virtio16 flags;
/* We chain unused descriptors via this, too */
__virtio16 next;
};