[PATCH V3 02/19] virtio-pci: split out modern device

From: Jason Wang
Date: Mon Jan 04 2021 - 01:56:56 EST

This patch splits out the virtio-pci modern device only attributes
into another structure. While at it, a dedicated probe method for
modern only attributes is introduced. This may help for split the
logic into a dedicated module.

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
drivers/virtio/virtio_pci_common.h | 25 +++--
drivers/virtio/virtio_pci_modern.c | 159 ++++++++++++++++-------------
2 files changed, 105 insertions(+), 79 deletions(-)

diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h
index b2f0eb4067cb..f35ff5b6b467 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -39,22 +39,16 @@ struct virtio_pci_vq_info {
unsigned msix_vector;
};

-/* Our device structure */
-struct virtio_pci_device {
- struct virtio_device vdev;
+struct virtio_pci_modern_device {
struct pci_dev *pci_dev;

- /* In legacy mode, these two point to within ->legacy. */
- /* Where to read and clear interrupt */
- u8 __iomem *isr;
-
- /* Modern only fields */
- /* The IO mapping for the PCI config space (non-legacy mode) */
struct virtio_pci_common_cfg __iomem *common;
/* Device-specific data (non-legacy mode) */
void __iomem *device;
/* Base of vq notifications (non-legacy mode). */
void __iomem *notify_base;
+ /* Where to read and clear interrupt */
+ u8 __iomem *isr;

/* So we can sanity-check accesses. */
size_t notify_len;
@@ -68,6 +62,19 @@ struct virtio_pci_device {

int modern_bars;

+ struct virtio_device_id id;
+};
+
+/* Our device structure */
+struct virtio_pci_device {
+ struct virtio_device vdev;
+ struct pci_dev *pci_dev;
+ struct virtio_pci_modern_device mdev;
+
+ /* In legacy mode, these two point to within ->legacy. */
+ /* Where to read and clear interrupt */
+ u8 __iomem *isr;
+
/* Legacy only field */
/* the IO mapping for the PCI config space */
void __iomem *ioaddr;
diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index df1481fd400c..524490a94ca4 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -141,7 +141,8 @@ static void __iomem *map_capability(struct pci_dev *dev, int off,
static u64 vp_get_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
u64 features;

vp_iowrite32(0, &cfg->device_feature_select);
@@ -166,7 +167,8 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features)
static int vp_finalize_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
u64 features = vdev->features;

/* Give virtio_ring a chance to accept features. */
@@ -194,12 +196,13 @@ static void vp_get(struct virtio_device *vdev, unsigned offset,
void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- void __iomem *device = vp_dev->device;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ void __iomem *device = mdev->device;
u8 b;
__le16 w;
__le32 l;

- BUG_ON(offset + len > vp_dev->device_len);
+ BUG_ON(offset + len > mdev->device_len);

switch (len) {
case 1:
@@ -231,12 +234,13 @@ static void vp_set(struct virtio_device *vdev, unsigned offset,
const void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- void __iomem *device = vp_dev->device;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ void __iomem *device = mdev->device;
u8 b;
__le16 w;
__le32 l;

- BUG_ON(offset + len > vp_dev->device_len);
+ BUG_ON(offset + len > mdev->device_len);

switch (len) {
case 1:
@@ -265,7 +269,8 @@ static void vp_set(struct virtio_device *vdev, unsigned offset,
static u32 vp_generation(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;

return vp_ioread8(&cfg->config_generation);
}
@@ -274,7 +279,8 @@ static u32 vp_generation(struct virtio_device *vdev)
static u8 vp_get_status(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;

return vp_ioread8(&cfg->device_status);
}
@@ -282,7 +288,8 @@ static u8 vp_get_status(struct virtio_device *vdev)
static void vp_set_status(struct virtio_device *vdev, u8 status)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;

/* We should never be setting status to 0. */
BUG_ON(status == 0);
@@ -292,7 +299,8 @@ static void vp_set_status(struct virtio_device *vdev, u8 status)
static void vp_reset(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;

/* 0 status means a reset. */
vp_iowrite8(0, &cfg->device_status);
@@ -309,7 +317,8 @@ static void vp_reset(struct virtio_device *vdev)

static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
{
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;

/* Setup the vector used for configuration events */
vp_iowrite16(vector, &cfg->msix_config);
@@ -326,7 +335,9 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
bool ctx,
u16 msix_vec)
{
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
struct virtqueue *vq;
u16 num, off;
int err;
@@ -369,25 +380,25 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
vp_iowrite64_twopart(virtqueue_get_used_addr(vq),
&cfg->queue_used_lo, &cfg->queue_used_hi);

- if (vp_dev->notify_base) {
+ if (mdev->notify_base) {
/* offset should not wrap */
- if ((u64)off * vp_dev->notify_offset_multiplier + 2
- > vp_dev->notify_len) {
- dev_warn(&vp_dev->pci_dev->dev,
+ if ((u64)off * mdev->notify_offset_multiplier + 2
+ > mdev->notify_len) {
+ dev_warn(&mdev->pci_dev->dev,
"bad notification offset %u (x %u) "
"for queue %u > %zd",
- off, vp_dev->notify_offset_multiplier,
- index, vp_dev->notify_len);
+ off, mdev->notify_offset_multiplier,
+ index, mdev->notify_len);
err = -EINVAL;
goto err_map_notify;
}
- vq->priv = (void __force *)vp_dev->notify_base +
- off * vp_dev->notify_offset_multiplier;
+ vq->priv = (void __force *)mdev->notify_base +
+ off * mdev->notify_offset_multiplier;
} else {
- vq->priv = (void __force *)map_capability(vp_dev->pci_dev,
- vp_dev->notify_map_cap, 2, 2,
- off * vp_dev->notify_offset_multiplier, 2,
- NULL);
+ vq->priv = (void __force *)map_capability(mdev->pci_dev,
+ mdev->notify_map_cap, 2, 2,
+ off * mdev->notify_offset_multiplier, 2,
+ NULL);
}

if (!vq->priv) {
@@ -407,8 +418,8 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
return vq;

err_assign_vector:
- if (!vp_dev->notify_base)
- pci_iounmap(vp_dev->pci_dev, (void __iomem __force *)vq->priv);
+ if (!mdev->notify_base)
+ pci_iounmap(mdev->pci_dev, (void __iomem __force *)vq->priv);
err_map_notify:
vring_del_virtqueue(vq);
return ERR_PTR(err);
@@ -421,7 +432,7 @@ static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
struct irq_affinity *desc)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_common_cfg __iomem *cfg = vp_dev->mdev.common;
struct virtqueue *vq;
int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc);

@@ -443,7 +454,9 @@ static void del_vq(struct virtio_pci_vq_info *info)
{
struct virtqueue *vq = info->vq;
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
- struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+

vp_iowrite16(vq->index, &cfg->queue_select);

@@ -454,8 +467,8 @@ static void del_vq(struct virtio_pci_vq_info *info)
vp_ioread16(&cfg->queue_msix_vector);
}

- if (!vp_dev->notify_base)
- pci_iounmap(vp_dev->pci_dev, (void __force __iomem *)vq->priv);
+ if (!mdev->notify_base)
+ pci_iounmap(mdev->pci_dev, (void __force __iomem *)vq->priv);

vring_del_virtqueue(vq);
}
@@ -693,6 +706,7 @@ static inline void check_offsets(void)
/* the PCI probing function */
int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
{
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
struct pci_dev *pci_dev = vp_dev->pci_dev;
int err, common, isr, notify, device;
u32 notify_length;
@@ -700,6 +714,8 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)

check_offsets();

+ mdev->pci_dev = pci_dev;
+
/* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
return -ENODEV;
@@ -708,17 +724,17 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
/* Transitional devices: use the PCI subsystem device id as
* virtio device id, same as legacy driver always did.
*/
- vp_dev->vdev.id.device = pci_dev->subsystem_device;
+ mdev->id.device = pci_dev->subsystem_device;
} else {
/* Modern devices: simply use PCI device id, but start from 0x1040. */
- vp_dev->vdev.id.device = pci_dev->device - 0x1040;
+ mdev->id.device = pci_dev->device - 0x1040;
}
- vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
+ mdev->id.vendor = pci_dev->subsystem_vendor;

/* check for a common config: if not, use legacy mode (bar 0). */
common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
IORESOURCE_IO | IORESOURCE_MEM,
- &vp_dev->modern_bars);
+ &mdev->modern_bars);
if (!common) {
dev_info(&pci_dev->dev,
"virtio_pci: leaving for legacy driver\n");
@@ -728,10 +744,10 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
/* If common is there, these should be too... */
isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
IORESOURCE_IO | IORESOURCE_MEM,
- &vp_dev->modern_bars);
+ &mdev->modern_bars);
notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
IORESOURCE_IO | IORESOURCE_MEM,
- &vp_dev->modern_bars);
+ &mdev->modern_bars);
if (!isr || !notify) {
dev_err(&pci_dev->dev,
"virtio_pci: missing capabilities %i/%i/%i\n",
@@ -751,31 +767,31 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
*/
device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
IORESOURCE_IO | IORESOURCE_MEM,
- &vp_dev->modern_bars);
+ &mdev->modern_bars);

- err = pci_request_selected_regions(pci_dev, vp_dev->modern_bars,
+ err = pci_request_selected_regions(pci_dev, mdev->modern_bars,
"virtio-pci-modern");
if (err)
return err;

err = -EINVAL;
- vp_dev->common = map_capability(pci_dev, common,
- sizeof(struct virtio_pci_common_cfg), 4,
- 0, sizeof(struct virtio_pci_common_cfg),
- NULL);
- if (!vp_dev->common)
+ mdev->common = map_capability(pci_dev, common,
+ sizeof(struct virtio_pci_common_cfg), 4,
+ 0, sizeof(struct virtio_pci_common_cfg),
+ NULL);
+ if (!mdev->common)
goto err_map_common;
- vp_dev->isr = map_capability(pci_dev, isr, sizeof(u8), 1,
- 0, 1,
- NULL);
- if (!vp_dev->isr)
+ mdev->isr = map_capability(pci_dev, isr, sizeof(u8), 1,
+ 0, 1,
+ NULL);
+ if (!mdev->isr)
goto err_map_isr;

/* Read notify_off_multiplier from config space. */
pci_read_config_dword(pci_dev,
notify + offsetof(struct virtio_pci_notify_cap,
notify_off_multiplier),
- &vp_dev->notify_offset_multiplier);
+ &mdev->notify_offset_multiplier);
/* Read notify length and offset from config space. */
pci_read_config_dword(pci_dev,
notify + offsetof(struct virtio_pci_notify_cap,
@@ -792,23 +808,23 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
* Otherwise, map each VQ individually later.
*/
if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
- vp_dev->notify_base = map_capability(pci_dev, notify, 2, 2,
- 0, notify_length,
- &vp_dev->notify_len);
- if (!vp_dev->notify_base)
+ mdev->notify_base = map_capability(pci_dev, notify, 2, 2,
+ 0, notify_length,
+ &mdev->notify_len);
+ if (!mdev->notify_base)
goto err_map_notify;
} else {
- vp_dev->notify_map_cap = notify;
+ mdev->notify_map_cap = notify;
}

/* Again, we don't know how much we should map, but PAGE_SIZE
* is more than enough for all existing devices.
*/
if (device) {
- vp_dev->device = map_capability(pci_dev, device, 0, 4,
- 0, PAGE_SIZE,
- &vp_dev->device_len);
- if (!vp_dev->device)
+ mdev->device = map_capability(pci_dev, device, 0, 4,
+ 0, PAGE_SIZE,
+ &mdev->device_len);
+ if (!mdev->device)
goto err_map_device;

vp_dev->vdev.config = &virtio_pci_config_ops;
@@ -819,29 +835,32 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
vp_dev->config_vector = vp_config_vector;
vp_dev->setup_vq = setup_vq;
vp_dev->del_vq = del_vq;
+ vp_dev->isr = mdev->isr;
+ vp_dev->vdev.id = mdev->id;

return 0;

err_map_device:
- if (vp_dev->notify_base)
- pci_iounmap(pci_dev, vp_dev->notify_base);
+ if (mdev->notify_base)
+ pci_iounmap(pci_dev, mdev->notify_base);
err_map_notify:
- pci_iounmap(pci_dev, vp_dev->isr);
+ pci_iounmap(pci_dev, mdev->isr);
err_map_isr:
- pci_iounmap(pci_dev, vp_dev->common);
+ pci_iounmap(pci_dev, mdev->common);
err_map_common:
return err;
}

void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev)
{
- struct pci_dev *pci_dev = vp_dev->pci_dev;
-
- if (vp_dev->device)
- pci_iounmap(pci_dev, vp_dev->device);
- if (vp_dev->notify_base)
- pci_iounmap(pci_dev, vp_dev->notify_base);
- pci_iounmap(pci_dev, vp_dev->isr);
- pci_iounmap(pci_dev, vp_dev->common);
- pci_release_selected_regions(pci_dev, vp_dev->modern_bars);
+ struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ struct pci_dev *pci_dev = mdev->pci_dev;
+
+ if (mdev->device)
+ pci_iounmap(pci_dev, mdev->device);
+ if (mdev->notify_base)
+ pci_iounmap(pci_dev, mdev->notify_base);
+ pci_iounmap(pci_dev, mdev->isr);
+ pci_iounmap(pci_dev, mdev->common);
+ pci_release_selected_regions(pci_dev, mdev->modern_bars);
}
--
2.25.1