2022-11-11 16:00:42

by Thomas Gleixner

[permalink] [raw]
Subject: [patch 27/39] PCI/MSI: Move pci_disable_msix() to api.c

From: Ahmed S. Darwish <[email protected]>

To distangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_disable_msix() and make its kernel-doc comprehensive.

Signed-off-by: Ahmed S. Darwish <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>

---
drivers/pci/msi/api.c | 24 ++++++++++++++++++++++++
drivers/pci/msi/msi.c | 14 +-------------
drivers/pci/msi/msi.h | 1 +
3 files changed, 26 insertions(+), 13 deletions(-)
---
diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index 83ea38ffa116..653a61868ae6 100644
--- a/drivers/pci/msi/api.c
+++ b/drivers/pci/msi/api.c
@@ -112,6 +112,30 @@ int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
EXPORT_SYMBOL(pci_enable_msix_range);

/**
+ * pci_disable_msix() - Disable MSI-X interrupt mode on device
+ * @dev: the PCI device to operate on
+ *
+ * Legacy device driver API to disable MSI-X interrupt mode on device,
+ * free earlier-allocated interrupt vectors, and restore INTx emulation.
+ * The PCI device Linux IRQ (@dev->irq) is restored to its default pin
+ * assertion IRQ. This is the cleanup pair of pci_enable_msix_range().
+ *
+ * NOTE: The newer pci_alloc_irq_vectors() / pci_free_irq_vectors() API
+ * pair should, in general, be used instead.
+ */
+void pci_disable_msix(struct pci_dev *dev)
+{
+ if (!pci_msi_enabled() || !dev || !dev->msix_enabled)
+ return;
+
+ msi_lock_descs(&dev->dev);
+ pci_msix_shutdown(dev);
+ pci_free_msi_irqs(dev);
+ msi_unlock_descs(&dev->dev);
+}
+EXPORT_SYMBOL(pci_disable_msix);
+
+/**
* pci_alloc_irq_vectors() - Allocate multiple device interrupt vectors
* @dev: the PCI device to operate on
* @min_vecs: minimum required number of vectors (must be >= 1)
diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index 1226d66da992..6fa90d07d2e4 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -736,7 +736,7 @@ static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
return msix_capability_init(dev, entries, nvec, affd);
}

-static void pci_msix_shutdown(struct pci_dev *dev)
+void pci_msix_shutdown(struct pci_dev *dev)
{
struct msi_desc *desc;

@@ -758,18 +758,6 @@ static void pci_msix_shutdown(struct pci_dev *dev)
pcibios_alloc_irq(dev);
}

-void pci_disable_msix(struct pci_dev *dev)
-{
- if (!pci_msi_enable || !dev || !dev->msix_enabled)
- return;
-
- msi_lock_descs(&dev->dev);
- pci_msix_shutdown(dev);
- pci_free_msi_irqs(dev);
- msi_unlock_descs(&dev->dev);
-}
-EXPORT_SYMBOL(pci_disable_msix);
-
int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
struct irq_affinity *affd)
{
diff --git a/drivers/pci/msi/msi.h b/drivers/pci/msi/msi.h
index 8c4a5289432d..77e2587f7e4f 100644
--- a/drivers/pci/msi/msi.h
+++ b/drivers/pci/msi/msi.h
@@ -86,6 +86,7 @@ static inline __attribute_const__ u32 msi_multi_mask(struct msi_desc *desc)

/* MSI internal functions invoked from the public APIs */
void pci_msi_shutdown(struct pci_dev *dev);
+void pci_msix_shutdown(struct pci_dev *dev);
void pci_free_msi_irqs(struct pci_dev *dev);
int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec, struct irq_affinity *affd);
int __pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, int minvec,



2022-11-16 16:38:56

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [patch 27/39] PCI/MSI: Move pci_disable_msix() to api.c

On Fri, Nov 11, 2022 at 02:54:58PM +0100, Thomas Gleixner wrote:
> From: Ahmed S. Darwish <[email protected]>
>
> To distangle the maze in msi.c, all exported device-driver MSI APIs are
> now to be grouped in one file, api.c.
>
> Move pci_disable_msix() and make its kernel-doc comprehensive.
>
> Signed-off-by: Ahmed S. Darwish <[email protected]>
> Signed-off-by: Thomas Gleixner <[email protected]>

Acked-by: Bjorn Helgaas <[email protected]>

Trivial question below.

> ---
> drivers/pci/msi/api.c | 24 ++++++++++++++++++++++++
> drivers/pci/msi/msi.c | 14 +-------------
> drivers/pci/msi/msi.h | 1 +
> 3 files changed, 26 insertions(+), 13 deletions(-)
> ---
> diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
> index 83ea38ffa116..653a61868ae6 100644
> --- a/drivers/pci/msi/api.c
> +++ b/drivers/pci/msi/api.c
> @@ -112,6 +112,30 @@ int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
> EXPORT_SYMBOL(pci_enable_msix_range);
>
> /**
> + * pci_disable_msix() - Disable MSI-X interrupt mode on device
> + * @dev: the PCI device to operate on
> + *
> + * Legacy device driver API to disable MSI-X interrupt mode on device,
> + * free earlier-allocated interrupt vectors, and restore INTx emulation.

Isn't INTx *emulation* a PCIe implementation detail? Doesn't seem
relevant to callers that it's emulated.

> + * The PCI device Linux IRQ (@dev->irq) is restored to its default pin
> + * assertion IRQ. This is the cleanup pair of pci_enable_msix_range().
> + *
> + * NOTE: The newer pci_alloc_irq_vectors() / pci_free_irq_vectors() API
> + * pair should, in general, be used instead.
> + */
> +void pci_disable_msix(struct pci_dev *dev)
> +{
> + if (!pci_msi_enabled() || !dev || !dev->msix_enabled)
> + return;
> +
> + msi_lock_descs(&dev->dev);
> + pci_msix_shutdown(dev);
> + pci_free_msi_irqs(dev);
> + msi_unlock_descs(&dev->dev);
> +}
> +EXPORT_SYMBOL(pci_disable_msix);
> +
> +/**
> * pci_alloc_irq_vectors() - Allocate multiple device interrupt vectors
> * @dev: the PCI device to operate on
> * @min_vecs: minimum required number of vectors (must be >= 1)
> diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
> index 1226d66da992..6fa90d07d2e4 100644
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -736,7 +736,7 @@ static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
> return msix_capability_init(dev, entries, nvec, affd);
> }
>
> -static void pci_msix_shutdown(struct pci_dev *dev)
> +void pci_msix_shutdown(struct pci_dev *dev)
> {
> struct msi_desc *desc;
>
> @@ -758,18 +758,6 @@ static void pci_msix_shutdown(struct pci_dev *dev)
> pcibios_alloc_irq(dev);
> }
>
> -void pci_disable_msix(struct pci_dev *dev)
> -{
> - if (!pci_msi_enable || !dev || !dev->msix_enabled)
> - return;
> -
> - msi_lock_descs(&dev->dev);
> - pci_msix_shutdown(dev);
> - pci_free_msi_irqs(dev);
> - msi_unlock_descs(&dev->dev);
> -}
> -EXPORT_SYMBOL(pci_disable_msix);
> -
> int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
> struct irq_affinity *affd)
> {
> diff --git a/drivers/pci/msi/msi.h b/drivers/pci/msi/msi.h
> index 8c4a5289432d..77e2587f7e4f 100644
> --- a/drivers/pci/msi/msi.h
> +++ b/drivers/pci/msi/msi.h
> @@ -86,6 +86,7 @@ static inline __attribute_const__ u32 msi_multi_mask(struct msi_desc *desc)
>
> /* MSI internal functions invoked from the public APIs */
> void pci_msi_shutdown(struct pci_dev *dev);
> +void pci_msix_shutdown(struct pci_dev *dev);
> void pci_free_msi_irqs(struct pci_dev *dev);
> int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec, struct irq_affinity *affd);
> int __pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, int minvec,
>

2022-11-16 17:45:48

by Thomas Gleixner

[permalink] [raw]
Subject: Re: [patch 27/39] PCI/MSI: Move pci_disable_msix() to api.c

On Wed, Nov 16 2022 at 10:26, Bjorn Helgaas wrote:
>> /**
>> + * pci_disable_msix() - Disable MSI-X interrupt mode on device
>> + * @dev: the PCI device to operate on
>> + *
>> + * Legacy device driver API to disable MSI-X interrupt mode on device,
>> + * free earlier-allocated interrupt vectors, and restore INTx emulation.
>
> Isn't INTx *emulation* a PCIe implementation detail? Doesn't seem
> relevant to callers that it's emulated.

Don't know how the emulation ended up there. It restores INTx which is
obvioulsy not a wire on PCIe... But yes, it's uninteresting.



Subject: [tip: irq/core] PCI/MSI: Move pci_disable_msix() to api.c

The following commit has been merged into the irq/core branch of tip:

Commit-ID: 18e1926b8c8b7c2249c24057d5f836c578e29f08
Gitweb: https://git.kernel.org/tip/18e1926b8c8b7c2249c24057d5f836c578e29f08
Author: Ahmed S. Darwish <[email protected]>
AuthorDate: Fri, 11 Nov 2022 14:54:58 +01:00
Committer: Thomas Gleixner <[email protected]>
CommitterDate: Thu, 17 Nov 2022 15:15:21 +01:00

PCI/MSI: Move pci_disable_msix() to api.c

To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_disable_msix() and make its kernel-doc comprehensive.

Signed-off-by: Ahmed S. Darwish <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Bjorn Helgaas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]


---
drivers/pci/msi/api.c | 24 ++++++++++++++++++++++++
drivers/pci/msi/msi.c | 14 +-------------
drivers/pci/msi/msi.h | 1 +
3 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index 83ea38f..20a580b 100644
--- a/drivers/pci/msi/api.c
+++ b/drivers/pci/msi/api.c
@@ -112,6 +112,30 @@ int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
EXPORT_SYMBOL(pci_enable_msix_range);

/**
+ * pci_disable_msix() - Disable MSI-X interrupt mode on device
+ * @dev: the PCI device to operate on
+ *
+ * Legacy device driver API to disable MSI-X interrupt mode on device,
+ * free earlier-allocated interrupt vectors, and restore INTx.
+ * The PCI device Linux IRQ (@dev->irq) is restored to its default pin
+ * assertion IRQ. This is the cleanup pair of pci_enable_msix_range().
+ *
+ * NOTE: The newer pci_alloc_irq_vectors() / pci_free_irq_vectors() API
+ * pair should, in general, be used instead.
+ */
+void pci_disable_msix(struct pci_dev *dev)
+{
+ if (!pci_msi_enabled() || !dev || !dev->msix_enabled)
+ return;
+
+ msi_lock_descs(&dev->dev);
+ pci_msix_shutdown(dev);
+ pci_free_msi_irqs(dev);
+ msi_unlock_descs(&dev->dev);
+}
+EXPORT_SYMBOL(pci_disable_msix);
+
+/**
* pci_alloc_irq_vectors() - Allocate multiple device interrupt vectors
* @dev: the PCI device to operate on
* @min_vecs: minimum required number of vectors (must be >= 1)
diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index 1226d66..6fa90d0 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -736,7 +736,7 @@ static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
return msix_capability_init(dev, entries, nvec, affd);
}

-static void pci_msix_shutdown(struct pci_dev *dev)
+void pci_msix_shutdown(struct pci_dev *dev)
{
struct msi_desc *desc;

@@ -758,18 +758,6 @@ static void pci_msix_shutdown(struct pci_dev *dev)
pcibios_alloc_irq(dev);
}

-void pci_disable_msix(struct pci_dev *dev)
-{
- if (!pci_msi_enable || !dev || !dev->msix_enabled)
- return;
-
- msi_lock_descs(&dev->dev);
- pci_msix_shutdown(dev);
- pci_free_msi_irqs(dev);
- msi_unlock_descs(&dev->dev);
-}
-EXPORT_SYMBOL(pci_disable_msix);
-
int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
struct irq_affinity *affd)
{
diff --git a/drivers/pci/msi/msi.h b/drivers/pci/msi/msi.h
index 8c4a528..77e2587 100644
--- a/drivers/pci/msi/msi.h
+++ b/drivers/pci/msi/msi.h
@@ -86,6 +86,7 @@ static inline __attribute_const__ u32 msi_multi_mask(struct msi_desc *desc)

/* MSI internal functions invoked from the public APIs */
void pci_msi_shutdown(struct pci_dev *dev);
+void pci_msix_shutdown(struct pci_dev *dev);
void pci_free_msi_irqs(struct pci_dev *dev);
int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec, struct irq_affinity *affd);
int __pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, int minvec,