[PATCH v3] vdpa/octeon_ep: Control PCI dev enabling manually

[PATCH v3] vdpa/octeon_ep: Control PCI dev enabling manually

[Philipp Stanner]

PCI region request functions such as pci_request_region() currently have
the problem of becoming sometimes managed functions, if
pcim_enable_device() instead of pci_enable_device() was called. The PCI
subsystem wants to remove this deprecated behavior from its interfaces.

octeopn_ep enables its device with pcim_enable_device() (for AF. PF uses
manual management), but does so only to get automatic disablement. The
driver wants to manage its PCI resources for AF manually, without devres.

The easiest way not to use automatic resource management at all is by
also handling device enable- and disablement manually.

Replace pcim_enable_device() with pci_enable_device(). Add the necessary
calls to pci_disable_device().

Signed-off-by: Philipp Stanner <phasta@kernel.org>
---
Changes in v3:
  - Only call pci_disable_device() for the PF version. For AF it would
    cause a WARN_ON because pcim_enable_device()'s callback will also
    try to disable.
---
 drivers/vdpa/octeon_ep/octep_vdpa_main.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/vdpa/octeon_ep/octep_vdpa_main.c b/drivers/vdpa/octeon_ep/octep_vdpa_main.c
index f3d4dda4e04c..9b49efd24391 100644
--- a/drivers/vdpa/octeon_ep/octep_vdpa_main.c
+++ b/drivers/vdpa/octeon_ep/octep_vdpa_main.c
@@ -454,6 +454,9 @@ static void octep_vdpa_remove_pf(struct pci_dev *pdev)
 		octep_iounmap_region(pdev, octpf->base, OCTEP_HW_MBOX_BAR);
 
 	octep_vdpa_pf_bar_expand(octpf);
+
+	/* The pf version does not use managed PCI. */
+	pci_disable_device(pdev);
 }
 
 static void octep_vdpa_vf_bar_shrink(struct pci_dev *pdev)
@@ -825,7 +828,7 @@ static int octep_vdpa_probe_pf(struct pci_dev *pdev)
 	struct octep_pf *octpf;
 	int ret;
 
-	ret = pcim_enable_device(pdev);
+	ret = pci_enable_device(pdev);
 	if (ret) {
 		dev_err(dev, "Failed to enable device\n");
 		return ret;
@@ -834,15 +837,17 @@ static int octep_vdpa_probe_pf(struct pci_dev *pdev)
 	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
 	if (ret) {
 		dev_err(dev, "No usable DMA configuration\n");
-		return ret;
+		goto disable_pci;
 	}
 	octpf = devm_kzalloc(dev, sizeof(*octpf), GFP_KERNEL);
-	if (!octpf)
-		return -ENOMEM;
+	if (!octpf) {
+		ret = -ENOMEM;
+		goto disable_pci;
+	}
 
 	ret = octep_iomap_region(pdev, octpf->base, OCTEP_HW_MBOX_BAR);
 	if (ret)
-		return ret;
+		goto disable_pci;
 
 	pci_set_master(pdev);
 	pci_set_drvdata(pdev, octpf);
@@ -856,6 +861,8 @@ static int octep_vdpa_probe_pf(struct pci_dev *pdev)
 
 unmap_region:
 	octep_iounmap_region(pdev, octpf->base, OCTEP_HW_MBOX_BAR);
+disable_pci:
+	pci_disable_device(pdev);
 	return ret;
 }
 
-- 
2.48.1

RE: [EXTERNAL] [PATCH v3] vdpa/octeon_ep: Control PCI dev enabling manually

[Vamsi Krishna Attunuru]

>-----Original Message-----
>From: Philipp Stanner <phasta@kernel.org>
>Sent: Thursday, April 24, 2025 5:19 PM
>To: Srujana Challa <schalla@marvell.com>; Vamsi Krishna Attunuru
><vattunuru@marvell.com>; Michael S. Tsirkin <mst@redhat.com>; Jason
>Wang <jasowang@redhat.com>; Xuan Zhuo <xuanzhuo@linux.alibaba.com>;
>Eugenio Pérez <eperezma@redhat.com>; Shijith Thotton
><sthotton@marvell.com>; Dan Carpenter <dan.carpenter@linaro.org>;
>Philipp Stanner <phasta@kernel.org>; Satha Koteswara Rao Kottidi
><skoteshwar@marvell.com>
>Cc: virtualization@lists.linux.dev; linux-kernel@vger.kernel.org
>Subject: [EXTERNAL] [PATCH v3] vdpa/octeon_ep: Control PCI dev enabling
>manually
>
>PCI region request functions such as pci_request_region() currently have the
>problem of becoming sometimes managed functions, if
>pcim_enable_device() instead of pci_enable_device() was called. The PCI
>subsystem wants to remove this deprecated 
>PCI region request functions such as pci_request_region() currently have the
>problem of becoming sometimes managed functions, if
>pcim_enable_device() instead of pci_enable_device() was called. The PCI
>subsystem wants to remove this deprecated behavior from its interfaces.
>
>octeopn_ep enables its device with pcim_enable_device() (for AF. PF uses
>manual management), but does so only to get automatic disablement. The
>driver wants to manage its PCI resources for AF manually, without devres.
>
>The easiest way not to use automatic resource management at all is by also
>handling device enable- and disablement manually.
>
>Replace pcim_enable_device() with pci_enable_device(). Add the necessary
>calls to pci_disable_device().
>
>Signed-off-by: Philipp Stanner <phasta@kernel.org>

Thanks, Philipp, for the patch. Patch looks good, minor nit AF --> VF
Acked-by: Vamsi Attunuru <vattunuru@marvell.com>

>---
>Changes in v3:
>  - Only call pci_disable_device() for the PF version. For AF it would
>    cause a WARN_ON because pcim_enable_device()'s callback will also
>    try to disable.
>---
> drivers/vdpa/octeon_ep/octep_vdpa_main.c | 17 ++++++++++++-----
> 1 file changed, 12 insertions(+), 5 deletions(-)
>
>diff --git a/drivers/vdpa/octeon_ep/octep_vdpa_main.c
>b/drivers/vdpa/octeon_ep/octep_vdpa_main.c
>index f3d4dda4e04c..9b49efd24391 100644
>--- a/drivers/vdpa/octeon_ep/octep_vdpa_main.c
>+++ b/drivers/vdpa/octeon_ep/octep_vdpa_main.c
>@@ -454,6 +454,9 @@ static void octep_vdpa_remove_pf(struct pci_dev
>*pdev)
> 		octep_iounmap_region(pdev, octpf->base,
>OCTEP_HW_MBOX_BAR);
>
> 	octep_vdpa_pf_bar_expand(octpf);
>+
>+	/* The pf version does not use managed PCI. */
>+	pci_disable_device(pdev);
> }
>
> static void octep_vdpa_vf_bar_shrink(struct pci_dev *pdev) @@ -825,7
>+828,7 @@ static int octep_vdpa_probe_pf(struct pci_dev *pdev)
> 	struct octep_pf *octpf;
> 	int ret;
>
>-	ret = pcim_enable_device(pdev);
>+	ret = pci_enable_device(pdev);
> 	if (ret) {
> 		dev_err(dev, "Failed to enable device\n");
> 		return ret;
>@@ -834,15 +837,17 @@ static int octep_vdpa_probe_pf(struct pci_dev
>*pdev)
> 	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
> 	if (ret) {
> 		dev_err(dev, "No usable DMA configuration\n");
>-		return ret;
>+		goto disable_pci;
> 	}
> 	octpf = devm_kzalloc(dev, sizeof(*octpf), GFP_KERNEL);
>-	if (!octpf)
>-		return -ENOMEM;
>+	if (!octpf) {
>+		ret = -ENOMEM;
>+		goto disable_pci;
>+	}
>
> 	ret = octep_iomap_region(pdev, octpf->base,
>OCTEP_HW_MBOX_BAR);
> 	if (ret)
>-		return ret;
>+		goto disable_pci;
>
> 	pci_set_master(pdev);
> 	pci_set_drvdata(pdev, octpf);
>@@ -856,6 +861,8 @@ static int octep_vdpa_probe_pf(struct pci_dev *pdev)
>
> unmap_region:
> 	octep_iounmap_region(pdev, octpf->base, OCTEP_HW_MBOX_BAR);
>+disable_pci:
>+	pci_disable_device(pdev);
> 	return ret;
> }
>
>--
>2.48.1