diff mbox series

[1/3] migration: update BAR space size

Message ID 20250218021507.40740-2-liulongfang@huawei.com (mailing list archive)
State New
Headers show
Series update live migration configuration region | expand

Commit Message

Longfang Liu Feb. 18, 2025, 2:15 a.m. UTC
On the new hardware platform, the live migration configuration region
is moved from VF to PF. The VF's own configuration space is
restored to the complete 64KB, and there is no need to divide the
size of the BAR configuration space equally.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 41 +++++++++++++++----
 1 file changed, 32 insertions(+), 9 deletions(-)

Comments

Shameer Kolothum Feb. 18, 2025, 10:20 a.m. UTC | #1
> -----Original Message-----
> From: liulongfang <liulongfang@huawei.com>
> Sent: Tuesday, February 18, 2025 2:15 AM
> To: alex.williamson@redhat.com; jgg@nvidia.com; Shameerali Kolothum
> Thodi <shameerali.kolothum.thodi@huawei.com>; Jonathan Cameron
> <jonathan.cameron@huawei.com>
> Cc: kvm@vger.kernel.org; linux-kernel@vger.kernel.org;
> linuxarm@openeuler.org; liulongfang <liulongfang@huawei.com>
> Subject: [PATCH 1/3] migration: update BAR space size
> 
> On the new hardware platform, the live migration configuration region
> is moved from VF to PF. The VF's own configuration space is
> restored to the complete 64KB, and there is no need to divide the
> size of the BAR configuration space equally.
> 
> Signed-off-by: Longfang Liu <liulongfang@huawei.com>
> ---
>  .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    | 41 +++++++++++++++----
>  1 file changed, 32 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> index 451c639299eb..599905dbb707 100644
> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> @@ -1195,6 +1195,33 @@ static struct hisi_qm *hisi_acc_get_pf_qm(struct
> pci_dev *pdev)
>  	return !IS_ERR(pf_qm) ? pf_qm : NULL;
>  }
> 
> +static size_t hisi_acc_get_resource_len(struct vfio_pci_core_device *vdev,
> +					unsigned int index)
> +{
> +	struct hisi_acc_vf_core_device *hisi_acc_vdev =
> +			hisi_acc_drvdata(vdev->pdev);
> +
> +	/*
> +	 * ACC VF dev 64KB BAR2 region consists of both functional
> +	 * register space and migration control register space, each
> +	 * uses 32KB BAR2 region, on the system with more than 64KB
> +	 * page size, even if the migration control register space
> +	 * is written by VM, it will only affects the VF.
> +	 *
> +	 * In order to support the live migration function in the
> +	 * system with a page size above 64KB, the driver needs
> +	 * to ensure that the VF region size is aligned with the
> +	 * system page size.

I didn't get this. Are you referring to kernel with 64K page size? And this is 
for new hardware or QM_HW_V3 one?

> +	 *
> +	 * On the new hardware platform, the live migration control register
> +	 * has been moved from VF to PF.
> +	 */
> +	if (hisi_acc_vdev->pf_qm->ver == QM_HW_V3)
> +		return (pci_resource_len(vdev->pdev, index) >> 1);
> +
> +	return pci_resource_len(vdev->pdev, index);
> +}
> +
>  static int hisi_acc_pci_rw_access_check(struct vfio_device *core_vdev,
>  					size_t count, loff_t *ppos,
>  					size_t *new_count)
> @@ -1205,8 +1232,9 @@ static int hisi_acc_pci_rw_access_check(struct
> vfio_device *core_vdev,
> 
>  	if (index == VFIO_PCI_BAR2_REGION_INDEX) {
>  		loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK;
> -		resource_size_t end = pci_resource_len(vdev->pdev, index) /
> 2;
> +		resource_size_t end;
> 
> +		end = hisi_acc_get_resource_len(vdev, index);
>  		/* Check if access is for migration control region */
>  		if (pos >= end)
>  			return -EINVAL;
> @@ -1227,8 +1255,9 @@ static int hisi_acc_vfio_pci_mmap(struct
> vfio_device *core_vdev,
>  	index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
>  	if (index == VFIO_PCI_BAR2_REGION_INDEX) {
>  		u64 req_len, pgoff, req_start;
> -		resource_size_t end = pci_resource_len(vdev->pdev, index) /
> 2;
> +		resource_size_t end;
> 
> +		end = PAGE_ALIGN(hisi_acc_get_resource_len(vdev, index));

So here, the whole BAR2 will be mapped to Guest in case of QM_HW_V3 &&
64K kernel as well, right?

Thanks,
Shameer

>  		req_len = vma->vm_end - vma->vm_start;
>  		pgoff = vma->vm_pgoff &
>  			((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
> @@ -1275,7 +1304,6 @@ static long hisi_acc_vfio_pci_ioctl(struct
> vfio_device *core_vdev, unsigned int
>  	if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
>  		struct vfio_pci_core_device *vdev =
>  			container_of(core_vdev, struct vfio_pci_core_device,
> vdev);
> -		struct pci_dev *pdev = vdev->pdev;
>  		struct vfio_region_info info;
>  		unsigned long minsz;
> 
> @@ -1290,12 +1318,7 @@ static long hisi_acc_vfio_pci_ioctl(struct
> vfio_device *core_vdev, unsigned int
>  		if (info.index == VFIO_PCI_BAR2_REGION_INDEX) {
>  			info.offset =
> VFIO_PCI_INDEX_TO_OFFSET(info.index);
> 
> -			/*
> -			 * ACC VF dev BAR2 region consists of both
> functional
> -			 * register space and migration control register
> space.
> -			 * Report only the functional region to Guest.
> -			 */
> -			info.size = pci_resource_len(pdev, info.index) / 2;
> +			info.size = hisi_acc_get_resource_len(vdev,
> info.index);
> 
>  			info.flags = VFIO_REGION_INFO_FLAG_READ |
>  					VFIO_REGION_INFO_FLAG_WRITE |
> --
> 2.24.0
diff mbox series

Patch

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index 451c639299eb..599905dbb707 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -1195,6 +1195,33 @@  static struct hisi_qm *hisi_acc_get_pf_qm(struct pci_dev *pdev)
 	return !IS_ERR(pf_qm) ? pf_qm : NULL;
 }
 
+static size_t hisi_acc_get_resource_len(struct vfio_pci_core_device *vdev,
+					unsigned int index)
+{
+	struct hisi_acc_vf_core_device *hisi_acc_vdev =
+			hisi_acc_drvdata(vdev->pdev);
+
+	/*
+	 * ACC VF dev 64KB BAR2 region consists of both functional
+	 * register space and migration control register space, each
+	 * uses 32KB BAR2 region, on the system with more than 64KB
+	 * page size, even if the migration control register space
+	 * is written by VM, it will only affects the VF.
+	 *
+	 * In order to support the live migration function in the
+	 * system with a page size above 64KB, the driver needs
+	 * to ensure that the VF region size is aligned with the
+	 * system page size.
+	 *
+	 * On the new hardware platform, the live migration control register
+	 * has been moved from VF to PF.
+	 */
+	if (hisi_acc_vdev->pf_qm->ver == QM_HW_V3)
+		return (pci_resource_len(vdev->pdev, index) >> 1);
+
+	return pci_resource_len(vdev->pdev, index);
+}
+
 static int hisi_acc_pci_rw_access_check(struct vfio_device *core_vdev,
 					size_t count, loff_t *ppos,
 					size_t *new_count)
@@ -1205,8 +1232,9 @@  static int hisi_acc_pci_rw_access_check(struct vfio_device *core_vdev,
 
 	if (index == VFIO_PCI_BAR2_REGION_INDEX) {
 		loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK;
-		resource_size_t end = pci_resource_len(vdev->pdev, index) / 2;
+		resource_size_t end;
 
+		end = hisi_acc_get_resource_len(vdev, index);
 		/* Check if access is for migration control region */
 		if (pos >= end)
 			return -EINVAL;
@@ -1227,8 +1255,9 @@  static int hisi_acc_vfio_pci_mmap(struct vfio_device *core_vdev,
 	index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
 	if (index == VFIO_PCI_BAR2_REGION_INDEX) {
 		u64 req_len, pgoff, req_start;
-		resource_size_t end = pci_resource_len(vdev->pdev, index) / 2;
+		resource_size_t end;
 
+		end = PAGE_ALIGN(hisi_acc_get_resource_len(vdev, index));
 		req_len = vma->vm_end - vma->vm_start;
 		pgoff = vma->vm_pgoff &
 			((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
@@ -1275,7 +1304,6 @@  static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
 	if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
 		struct vfio_pci_core_device *vdev =
 			container_of(core_vdev, struct vfio_pci_core_device, vdev);
-		struct pci_dev *pdev = vdev->pdev;
 		struct vfio_region_info info;
 		unsigned long minsz;
 
@@ -1290,12 +1318,7 @@  static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int
 		if (info.index == VFIO_PCI_BAR2_REGION_INDEX) {
 			info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
 
-			/*
-			 * ACC VF dev BAR2 region consists of both functional
-			 * register space and migration control register space.
-			 * Report only the functional region to Guest.
-			 */
-			info.size = pci_resource_len(pdev, info.index) / 2;
+			info.size = hisi_acc_get_resource_len(vdev, info.index);
 
 			info.flags = VFIO_REGION_INFO_FLAG_READ |
 					VFIO_REGION_INFO_FLAG_WRITE |