[PATCH 0/5] VDPA mlx5 fixes

[PATCH 0/5] VDPA mlx5 fixes

[Eli Cohen]

Hi Michael,

The following series contains fixes to mlx5 vdpa driver.  Included first
is Siwei's fix to queried MTU was already reviewed a while ago and is
not in your tree.

Patches 2 and 3 are required to allow mlx5_vdpa run on sub functions.

This series contains patches that were included in Parav's series
http://lists.infradead.org/pipermail/linux-mtd/2016-January/064878.html
but that series will be sent again at a later time.

Eli Cohen (4):
  vdpa/mlx5: Use the correct dma device when registering memory
  vdpa/mlx5: Retrieve BAR address suitable any function
  vdpa/mlx5: Fix wrong use of bit numbers
  vdpa/mlx5: Fix suspend/resume index restoration

Si-Wei Liu (1):
  vdpa/mlx5: should exclude header length and fcs from mtu

 drivers/vdpa/mlx5/core/mlx5_vdpa.h |  4 +++
 drivers/vdpa/mlx5/core/mr.c        |  9 +++++--
 drivers/vdpa/mlx5/core/resources.c |  3 ++-
 drivers/vdpa/mlx5/net/mlx5_vnet.c  | 40 ++++++++++++++++++------------
 4 files changed, 37 insertions(+), 19 deletions(-)

-- 
2.30.1

[PATCH 1/5] vdpa/mlx5: should exclude header length and fcs from mtu

[Eli Cohen]

From: Si-Wei Liu <si-wei.liu@oracle.com>

When feature VIRTIO_NET_F_MTU is negotiated on mlx5_vdpa,
22 extra bytes worth of MTU length is shown in guest.
This is because the mlx5_query_port_max_mtu API returns
the "hardware" MTU value, which does not just contain the
 Ethernet payload, but includes extra lengths starting
from the Ethernet header up to the FCS altogether.

Fix the MTU so packets won't get dropped silently.

Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eli Cohen <elic@nvidia.com>
---
 drivers/vdpa/mlx5/core/mlx5_vdpa.h |  4 ++++
 drivers/vdpa/mlx5/net/mlx5_vnet.c  | 15 ++++++++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index 08f742fd2409..b6cc53ba980c 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -4,9 +4,13 @@
 #ifndef __MLX5_VDPA_H__
 #define __MLX5_VDPA_H__
 
+#include <linux/etherdevice.h>
+#include <linux/if_vlan.h>
 #include <linux/vdpa.h>
 #include <linux/mlx5/driver.h>
 
+#define MLX5V_ETH_HARD_MTU (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN)
+
 struct mlx5_vdpa_direct_mr {
 	u64 start;
 	u64 end;
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 71397fdafa6a..a49ebb250253 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1907,6 +1907,19 @@ static const struct vdpa_config_ops mlx5_vdpa_ops = {
 	.free = mlx5_vdpa_free,
 };
 
+static int query_mtu(struct mlx5_core_dev *mdev, u16 *mtu)
+{
+	u16 hw_mtu;
+	int err;
+
+	err = mlx5_query_nic_vport_mtu(mdev, &hw_mtu);
+	if (err)
+		return err;
+
+	*mtu = hw_mtu - MLX5V_ETH_HARD_MTU;
+	return 0;
+}
+
 static int alloc_resources(struct mlx5_vdpa_net *ndev)
 {
 	struct mlx5_vdpa_net_resources *res = &ndev->res;
@@ -1992,7 +2005,7 @@ static int mlx5v_probe(struct auxiliary_device *adev,
 	init_mvqs(ndev);
 	mutex_init(&ndev->reslock);
 	config = &ndev->config;
-	err = mlx5_query_nic_vport_mtu(mdev, &ndev->mtu);
+	err = query_mtu(mdev, &ndev->mtu);
 	if (err)
 		goto err_mtu;
 
-- 
2.30.1

[PATCH 2/5] vdpa/mlx5: Use the correct dma device when registering memory

[Eli Cohen]

In cases where the vdpa instance uses a SF (sub function), the DMA
device is the parent device. Use a function to retrieve the correct DMA
device.

Fixes: 1958fc2f0712 ("net/mlx5: SF, Add auxiliary device driver")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
---
 drivers/vdpa/mlx5/core/mr.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/vdpa/mlx5/core/mr.c b/drivers/vdpa/mlx5/core/mr.c
index d300f799efcd..3908ff28eec0 100644
--- a/drivers/vdpa/mlx5/core/mr.c
+++ b/drivers/vdpa/mlx5/core/mr.c
@@ -219,6 +219,11 @@ static void destroy_indirect_key(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_m
 	mlx5_vdpa_destroy_mkey(mvdev, &mkey->mkey);
 }
 
+static struct device *get_dma_device(struct mlx5_vdpa_dev *mvdev)
+{
+	return &mvdev->mdev->pdev->dev;
+}
+
 static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr *mr,
 			 struct vhost_iotlb *iotlb)
 {
@@ -234,7 +239,7 @@ static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr
 	u64 pa;
 	u64 paend;
 	struct scatterlist *sg;
-	struct device *dma = mvdev->mdev->device;
+	struct device *dma = get_dma_device(mvdev);
 
 	for (map = vhost_iotlb_itree_first(iotlb, mr->start, mr->end - 1);
 	     map; map = vhost_iotlb_itree_next(map, start, mr->end - 1)) {
@@ -291,7 +296,7 @@ static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr
 
 static void unmap_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr *mr)
 {
-	struct device *dma = mvdev->mdev->device;
+	struct device *dma = get_dma_device(mvdev);
 
 	destroy_direct_mr(mvdev, mr);
 	dma_unmap_sg_attrs(dma, mr->sg_head.sgl, mr->nsg, DMA_BIDIRECTIONAL, 0);
-- 
2.30.1

Re: [PATCH 2/5] vdpa/mlx5: Use the correct dma device when registering memory

[Jason Wang]

在 2021/4/8 下午5:10, Eli Cohen 写道:
> In cases where the vdpa instance uses a SF (sub function), the DMA
> device is the parent device. Use a function to retrieve the correct DMA
> device.
>
> Fixes: 1958fc2f0712 ("net/mlx5: SF, Add auxiliary device driver")
> Signed-off-by: Eli Cohen <elic@nvidia.com>
> Reviewed-by: Parav Pandit <parav@nvidia.com>


Acked-by: Jason Wang <jasowang@redhat.com>


> ---
>   drivers/vdpa/mlx5/core/mr.c | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vdpa/mlx5/core/mr.c b/drivers/vdpa/mlx5/core/mr.c
> index d300f799efcd..3908ff28eec0 100644
> --- a/drivers/vdpa/mlx5/core/mr.c
> +++ b/drivers/vdpa/mlx5/core/mr.c
> @@ -219,6 +219,11 @@ static void destroy_indirect_key(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_m
>   	mlx5_vdpa_destroy_mkey(mvdev, &mkey->mkey);
>   }
>   
> +static struct device *get_dma_device(struct mlx5_vdpa_dev *mvdev)
> +{
> +	return &mvdev->mdev->pdev->dev;
> +}
> +
>   static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr *mr,
>   			 struct vhost_iotlb *iotlb)
>   {
> @@ -234,7 +239,7 @@ static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr
>   	u64 pa;
>   	u64 paend;
>   	struct scatterlist *sg;
> -	struct device *dma = mvdev->mdev->device;
> +	struct device *dma = get_dma_device(mvdev);
>   
>   	for (map = vhost_iotlb_itree_first(iotlb, mr->start, mr->end - 1);
>   	     map; map = vhost_iotlb_itree_next(map, start, mr->end - 1)) {
> @@ -291,7 +296,7 @@ static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr
>   
>   static void unmap_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr *mr)
>   {
> -	struct device *dma = mvdev->mdev->device;
> +	struct device *dma = get_dma_device(mvdev);
>   
>   	destroy_direct_mr(mvdev, mr);
>   	dma_unmap_sg_attrs(dma, mr->sg_head.sgl, mr->nsg, DMA_BIDIRECTIONAL, 0);

[PATCH 3/5] vdpa/mlx5: Retrieve BAR address suitable any function

[Eli Cohen]

struct mlx5_core_dev has a bar_addr field that contains the correct bar
address for the function regardless of whether it is pci function or sub
function. Use it.

Fixes: 1958fc2f0712 ("net/mlx5: SF, Add auxiliary device driver")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
---
 drivers/vdpa/mlx5/core/resources.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/vdpa/mlx5/core/resources.c b/drivers/vdpa/mlx5/core/resources.c
index 96e6421c5d1c..6521cbd0f5c2 100644
--- a/drivers/vdpa/mlx5/core/resources.c
+++ b/drivers/vdpa/mlx5/core/resources.c
@@ -246,7 +246,8 @@ int mlx5_vdpa_alloc_resources(struct mlx5_vdpa_dev *mvdev)
 	if (err)
 		goto err_key;
 
-	kick_addr = pci_resource_start(mdev->pdev, 0) + offset;
+	kick_addr = mdev->bar_addr + offset;
+
 	res->kick_addr = ioremap(kick_addr, PAGE_SIZE);
 	if (!res->kick_addr) {
 		err = -ENOMEM;
-- 
2.30.1

Re: [PATCH 3/5] vdpa/mlx5: Retrieve BAR address suitable any function

[Jason Wang]

在 2021/4/8 下午5:10, Eli Cohen 写道:
> struct mlx5_core_dev has a bar_addr field that contains the correct bar
> address for the function regardless of whether it is pci function or sub
> function. Use it.
>
> Fixes: 1958fc2f0712 ("net/mlx5: SF, Add auxiliary device driver")
> Signed-off-by: Eli Cohen <elic@nvidia.com>
> Reviewed-by: Parav Pandit <parav@nvidia.com>


Acked-by: Jason Wang <jasowang@redhat.com>


> ---
>   drivers/vdpa/mlx5/core/resources.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/vdpa/mlx5/core/resources.c b/drivers/vdpa/mlx5/core/resources.c
> index 96e6421c5d1c..6521cbd0f5c2 100644
> --- a/drivers/vdpa/mlx5/core/resources.c
> +++ b/drivers/vdpa/mlx5/core/resources.c
> @@ -246,7 +246,8 @@ int mlx5_vdpa_alloc_resources(struct mlx5_vdpa_dev *mvdev)
>   	if (err)
>   		goto err_key;
>   
> -	kick_addr = pci_resource_start(mdev->pdev, 0) + offset;
> +	kick_addr = mdev->bar_addr + offset;
> +
>   	res->kick_addr = ioremap(kick_addr, PAGE_SIZE);
>   	if (!res->kick_addr) {
>   		err = -ENOMEM;

[PATCH 4/5] vdpa/mlx5: Fix wrong use of bit numbers

[Eli Cohen]

VIRTIO_F_VERSION_1 is a bit number. Use BIT_ULL() with mask
conditionals.

Also, in mlx5_vdpa_is_little_endian() use BIT_ULL for consistency with
the rest of the code.

Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
Signed-off-by: Eli Cohen <elic@nvidia.com>
---
 drivers/vdpa/mlx5/net/mlx5_vnet.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index a49ebb250253..6fe61fc57790 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -820,7 +820,7 @@ static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque
 	MLX5_SET(virtio_q, vq_ctx, event_qpn_or_msix, mvq->fwqp.mqp.qpn);
 	MLX5_SET(virtio_q, vq_ctx, queue_size, mvq->num_ent);
 	MLX5_SET(virtio_q, vq_ctx, virtio_version_1_0,
-		 !!(ndev->mvdev.actual_features & VIRTIO_F_VERSION_1));
+		 !!(ndev->mvdev.actual_features & BIT_ULL(VIRTIO_F_VERSION_1)));
 	MLX5_SET64(virtio_q, vq_ctx, desc_addr, mvq->desc_addr);
 	MLX5_SET64(virtio_q, vq_ctx, used_addr, mvq->device_addr);
 	MLX5_SET64(virtio_q, vq_ctx, available_addr, mvq->driver_addr);
@@ -1554,7 +1554,7 @@ static void clear_virtqueues(struct mlx5_vdpa_net *ndev)
 static inline bool mlx5_vdpa_is_little_endian(struct mlx5_vdpa_dev *mvdev)
 {
 	return virtio_legacy_is_little_endian() ||
-		(mvdev->actual_features & (1ULL << VIRTIO_F_VERSION_1));
+		(mvdev->actual_features & BIT_ULL(VIRTIO_F_VERSION_1));
 }
 
 static __virtio16 cpu_to_mlx5vdpa16(struct mlx5_vdpa_dev *mvdev, u16 val)
-- 
2.30.1

Re: [PATCH 4/5] vdpa/mlx5: Fix wrong use of bit numbers

[Jason Wang]

在 2021/4/8 下午5:10, Eli Cohen 写道:
> VIRTIO_F_VERSION_1 is a bit number. Use BIT_ULL() with mask
> conditionals.
>
> Also, in mlx5_vdpa_is_little_endian() use BIT_ULL for consistency with
> the rest of the code.
>
> Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
> Signed-off-by: Eli Cohen <elic@nvidia.com>


Acked-by: Jason Wang <jasowang@redhat.com>


> ---
>   drivers/vdpa/mlx5/net/mlx5_vnet.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index a49ebb250253..6fe61fc57790 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -820,7 +820,7 @@ static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque
>   	MLX5_SET(virtio_q, vq_ctx, event_qpn_or_msix, mvq->fwqp.mqp.qpn);
>   	MLX5_SET(virtio_q, vq_ctx, queue_size, mvq->num_ent);
>   	MLX5_SET(virtio_q, vq_ctx, virtio_version_1_0,
> -		 !!(ndev->mvdev.actual_features & VIRTIO_F_VERSION_1));
> +		 !!(ndev->mvdev.actual_features & BIT_ULL(VIRTIO_F_VERSION_1)));
>   	MLX5_SET64(virtio_q, vq_ctx, desc_addr, mvq->desc_addr);
>   	MLX5_SET64(virtio_q, vq_ctx, used_addr, mvq->device_addr);
>   	MLX5_SET64(virtio_q, vq_ctx, available_addr, mvq->driver_addr);
> @@ -1554,7 +1554,7 @@ static void clear_virtqueues(struct mlx5_vdpa_net *ndev)
>   static inline bool mlx5_vdpa_is_little_endian(struct mlx5_vdpa_dev *mvdev)
>   {
>   	return virtio_legacy_is_little_endian() ||
> -		(mvdev->actual_features & (1ULL << VIRTIO_F_VERSION_1));
> +		(mvdev->actual_features & BIT_ULL(VIRTIO_F_VERSION_1));
>   }
>   
>   static __virtio16 cpu_to_mlx5vdpa16(struct mlx5_vdpa_dev *mvdev, u16 val)

[PATCH 5/5] vdpa/mlx5: Fix suspend/resume index restoration

[Eli Cohen]

When we suspend the VM, the VDPA interface will be reset. When the VM is
resumed again, clear_virtqueues() will clear the available and used
indices resulting in hardware virqtqueue objects becoming out of sync.
We can avoid this function alltogether since qemu will clear them if
required, e.g. when the VM went through a reboot.

Moreover, since the hw available and used indices should always be
identical on query and should be restored to the same value same value
for virtqueues that complete in order, we set the single value provided
by set_vq_state(). In get_vq_state() we return the value of hardware
used index.

Fixes: b35ccebe3ef7 ("vdpa/mlx5: Restore the hardware used index after change map")
Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
Signed-off-by: Eli Cohen <elic@nvidia.com>
---
 drivers/vdpa/mlx5/net/mlx5_vnet.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 6fe61fc57790..4d2809c7d4e3 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1169,6 +1169,7 @@ static void suspend_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *m
 		return;
 	}
 	mvq->avail_idx = attr.available_index;
+	mvq->used_idx = attr.used_index;
 }
 
 static void suspend_vqs(struct mlx5_vdpa_net *ndev)
@@ -1426,6 +1427,7 @@ static int mlx5_vdpa_set_vq_state(struct vdpa_device *vdev, u16 idx,
 		return -EINVAL;
 	}
 
+	mvq->used_idx = state->avail_index;
 	mvq->avail_idx = state->avail_index;
 	return 0;
 }
@@ -1443,7 +1445,11 @@ static int mlx5_vdpa_get_vq_state(struct vdpa_device *vdev, u16 idx, struct vdpa
 	 * that cares about emulating the index after vq is stopped.
 	 */
 	if (!mvq->initialized) {
-		state->avail_index = mvq->avail_idx;
+		/* Firmware returns a wrong value for the available index.
+		 * Since both values should be identical, we take the value of
+		 * used_idx which is reported correctly.
+		 */
+		state->avail_index = mvq->used_idx;
 		return 0;
 	}
 
@@ -1452,7 +1458,7 @@ static int mlx5_vdpa_get_vq_state(struct vdpa_device *vdev, u16 idx, struct vdpa
 		mlx5_vdpa_warn(mvdev, "failed to query virtqueue\n");
 		return err;
 	}
-	state->avail_index = attr.available_index;
+	state->avail_index = attr.used_index;
 	return 0;
 }
 
@@ -1540,16 +1546,6 @@ static void teardown_virtqueues(struct mlx5_vdpa_net *ndev)
 	}
 }
 
-static void clear_virtqueues(struct mlx5_vdpa_net *ndev)
-{
-	int i;
-
-	for (i = ndev->mvdev.max_vqs - 1; i >= 0; i--) {
-		ndev->vqs[i].avail_idx = 0;
-		ndev->vqs[i].used_idx = 0;
-	}
-}
-
 /* TODO: cross-endian support */
 static inline bool mlx5_vdpa_is_little_endian(struct mlx5_vdpa_dev *mvdev)
 {
@@ -1785,7 +1781,6 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
 	if (!status) {
 		mlx5_vdpa_info(mvdev, "performing device reset\n");
 		teardown_driver(ndev);
-		clear_virtqueues(ndev);
 		mlx5_vdpa_destroy_mr(&ndev->mvdev);
 		ndev->mvdev.status = 0;
 		ndev->mvdev.mlx_features = 0;
-- 
2.30.1

Re: [PATCH 5/5] vdpa/mlx5: Fix suspend/resume index restoration

[Jason Wang]

在 2021/4/8 下午5:10, Eli Cohen 写道:
> When we suspend the VM, the VDPA interface will be reset. When the VM is
> resumed again, clear_virtqueues() will clear the available and used
> indices resulting in hardware virqtqueue objects becoming out of sync.
> We can avoid this function alltogether since qemu will clear them if
> required, e.g. when the VM went through a reboot.
>
> Moreover, since the hw available and used indices should always be
> identical on query and should be restored to the same value same value
> for virtqueues that complete in order, we set the single value provided
> by set_vq_state(). In get_vq_state() we return the value of hardware
> used index.
>
> Fixes: b35ccebe3ef7 ("vdpa/mlx5: Restore the hardware used index after change map")
> Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
> Signed-off-by: Eli Cohen <elic@nvidia.com>
> ---


Acked-by: Jason Wang <jasowang@redhat.com>


>   drivers/vdpa/mlx5/net/mlx5_vnet.c | 21 ++++++++-------------
>   1 file changed, 8 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index 6fe61fc57790..4d2809c7d4e3 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -1169,6 +1169,7 @@ static void suspend_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *m
>   		return;
>   	}
>   	mvq->avail_idx = attr.available_index;
> +	mvq->used_idx = attr.used_index;
>   }
>   
>   static void suspend_vqs(struct mlx5_vdpa_net *ndev)
> @@ -1426,6 +1427,7 @@ static int mlx5_vdpa_set_vq_state(struct vdpa_device *vdev, u16 idx,
>   		return -EINVAL;
>   	}
>   
> +	mvq->used_idx = state->avail_index;
>   	mvq->avail_idx = state->avail_index;
>   	return 0;
>   }
> @@ -1443,7 +1445,11 @@ static int mlx5_vdpa_get_vq_state(struct vdpa_device *vdev, u16 idx, struct vdpa
>   	 * that cares about emulating the index after vq is stopped.
>   	 */
>   	if (!mvq->initialized) {
> -		state->avail_index = mvq->avail_idx;
> +		/* Firmware returns a wrong value for the available index.
> +		 * Since both values should be identical, we take the value of
> +		 * used_idx which is reported correctly.
> +		 */
> +		state->avail_index = mvq->used_idx;
>   		return 0;
>   	}
>   
> @@ -1452,7 +1458,7 @@ static int mlx5_vdpa_get_vq_state(struct vdpa_device *vdev, u16 idx, struct vdpa
>   		mlx5_vdpa_warn(mvdev, "failed to query virtqueue\n");
>   		return err;
>   	}
> -	state->avail_index = attr.available_index;
> +	state->avail_index = attr.used_index;
>   	return 0;
>   }
>   
> @@ -1540,16 +1546,6 @@ static void teardown_virtqueues(struct mlx5_vdpa_net *ndev)
>   	}
>   }
>   
> -static void clear_virtqueues(struct mlx5_vdpa_net *ndev)
> -{
> -	int i;
> -
> -	for (i = ndev->mvdev.max_vqs - 1; i >= 0; i--) {
> -		ndev->vqs[i].avail_idx = 0;
> -		ndev->vqs[i].used_idx = 0;
> -	}
> -}
> -
>   /* TODO: cross-endian support */
>   static inline bool mlx5_vdpa_is_little_endian(struct mlx5_vdpa_dev *mvdev)
>   {
> @@ -1785,7 +1781,6 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
>   	if (!status) {
>   		mlx5_vdpa_info(mvdev, "performing device reset\n");
>   		teardown_driver(ndev);
> -		clear_virtqueues(ndev);
>   		mlx5_vdpa_destroy_mr(&ndev->mvdev);
>   		ndev->mvdev.status = 0;
>   		ndev->mvdev.mlx_features = 0;

Re: [PATCH 0/5] VDPA mlx5 fixes

[Greg KH]

On Thu, Apr 08, 2021 at 12:10:42PM +0300, Eli Cohen wrote:
> Hi Michael,
> 
> The following series contains fixes to mlx5 vdpa driver.  Included first
> is Siwei's fix to queried MTU was already reviewed a while ago and is
> not in your tree.
> 
> Patches 2 and 3 are required to allow mlx5_vdpa run on sub functions.
> 
> This series contains patches that were included in Parav's series
> http://lists.infradead.org/pipermail/linux-mtd/2016-January/064878.html
> but that series will be sent again at a later time.
> 
> Eli Cohen (4):
>   vdpa/mlx5: Use the correct dma device when registering memory
>   vdpa/mlx5: Retrieve BAR address suitable any function
>   vdpa/mlx5: Fix wrong use of bit numbers
>   vdpa/mlx5: Fix suspend/resume index restoration
> 
> Si-Wei Liu (1):
>   vdpa/mlx5: should exclude header length and fcs from mtu
> 
>  drivers/vdpa/mlx5/core/mlx5_vdpa.h |  4 +++
>  drivers/vdpa/mlx5/core/mr.c        |  9 +++++--
>  drivers/vdpa/mlx5/core/resources.c |  3 ++-
>  drivers/vdpa/mlx5/net/mlx5_vnet.c  | 40 ++++++++++++++++++------------
>  4 files changed, 37 insertions(+), 19 deletions(-)
> 
> -- 
> 2.30.1
> 


<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>