diff mbox series

[V2,22/23] genirq/msi: Handle PCI/MSI allocation fail in core code

Message ID 20211206210225.046615302@linutronix.de (mailing list archive)
State Not Applicable
Headers show
Series genirq/msi, PCI/MSI: Spring cleaning - Part 1 | expand

Commit Message

Thomas Gleixner Dec. 6, 2021, 10:27 p.m. UTC
Get rid of yet another irqdomain callback and let the core code return the
already available information of how many descriptors could be allocated.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
---
 drivers/pci/msi/irqdomain.c |   13 -------------
 include/linux/msi.h         |    5 +----
 kernel/irq/msi.c            |   29 +++++++++++++++++++++++++----
 3 files changed, 26 insertions(+), 21 deletions(-)

Comments

Greg KH Dec. 7, 2021, 7:48 a.m. UTC | #1
On Mon, Dec 06, 2021 at 11:27:59PM +0100, Thomas Gleixner wrote:
> Get rid of yet another irqdomain callback and let the core code return the
> already available information of how many descriptors could be allocated.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Tested-by: Juergen Gross <jgross@suse.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bjorn Helgaas Dec. 7, 2021, 9:02 p.m. UTC | #2
On Mon, Dec 06, 2021 at 11:27:59PM +0100, Thomas Gleixner wrote:
> Get rid of yet another irqdomain callback and let the core code return the
> already available information of how many descriptors could be allocated.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Tested-by: Juergen Gross <jgross@suse.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>	# PCI

> ---
>  drivers/pci/msi/irqdomain.c |   13 -------------
>  include/linux/msi.h         |    5 +----
>  kernel/irq/msi.c            |   29 +++++++++++++++++++++++++----
>  3 files changed, 26 insertions(+), 21 deletions(-)
> 
> --- a/drivers/pci/msi/irqdomain.c
> +++ b/drivers/pci/msi/irqdomain.c
> @@ -95,16 +95,6 @@ static int pci_msi_domain_check_cap(stru
>  	return 0;
>  }
>  
> -static int pci_msi_domain_handle_error(struct irq_domain *domain,
> -				       struct msi_desc *desc, int error)
> -{
> -	/* Special handling to support __pci_enable_msi_range() */
> -	if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC)
> -		return 1;
> -
> -	return error;
> -}
> -
>  static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
>  				    struct msi_desc *desc)
>  {
> @@ -115,7 +105,6 @@ static void pci_msi_domain_set_desc(msi_
>  static struct msi_domain_ops pci_msi_domain_ops_default = {
>  	.set_desc	= pci_msi_domain_set_desc,
>  	.msi_check	= pci_msi_domain_check_cap,
> -	.handle_error	= pci_msi_domain_handle_error,
>  };
>  
>  static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
> @@ -129,8 +118,6 @@ static void pci_msi_domain_update_dom_op
>  			ops->set_desc = pci_msi_domain_set_desc;
>  		if (ops->msi_check == NULL)
>  			ops->msi_check = pci_msi_domain_check_cap;
> -		if (ops->handle_error == NULL)
> -			ops->handle_error = pci_msi_domain_handle_error;
>  	}
>  }
>  
> --- a/include/linux/msi.h
> +++ b/include/linux/msi.h
> @@ -286,7 +286,6 @@ struct msi_domain_info;
>   * @msi_check:		Callback for verification of the domain/info/dev data
>   * @msi_prepare:	Prepare the allocation of the interrupts in the domain
>   * @set_desc:		Set the msi descriptor for an interrupt
> - * @handle_error:	Optional error handler if the allocation fails
>   * @domain_alloc_irqs:	Optional function to override the default allocation
>   *			function.
>   * @domain_free_irqs:	Optional function to override the default free
> @@ -295,7 +294,7 @@ struct msi_domain_info;
>   * @get_hwirq, @msi_init and @msi_free are callbacks used by the underlying
>   * irqdomain.
>   *
> - * @msi_check, @msi_prepare, @handle_error and @set_desc are callbacks used by
> + * @msi_check, @msi_prepare and @set_desc are callbacks used by
>   * msi_domain_alloc/free_irqs().
>   *
>   * @domain_alloc_irqs, @domain_free_irqs can be used to override the
> @@ -332,8 +331,6 @@ struct msi_domain_ops {
>  				       msi_alloc_info_t *arg);
>  	void		(*set_desc)(msi_alloc_info_t *arg,
>  				    struct msi_desc *desc);
> -	int		(*handle_error)(struct irq_domain *domain,
> -					struct msi_desc *desc, int error);
>  	int		(*domain_alloc_irqs)(struct irq_domain *domain,
>  					     struct device *dev, int nvec);
>  	void		(*domain_free_irqs)(struct irq_domain *domain,
> --- a/kernel/irq/msi.c
> +++ b/kernel/irq/msi.c
> @@ -538,6 +538,27 @@ static bool msi_check_reservation_mode(s
>  	return desc->pci.msi_attrib.is_msix || desc->pci.msi_attrib.can_mask;
>  }
>  
> +static int msi_handle_pci_fail(struct irq_domain *domain, struct msi_desc *desc,
> +			       int allocated)
> +{
> +	switch(domain->bus_token) {
> +	case DOMAIN_BUS_PCI_MSI:
> +	case DOMAIN_BUS_VMD_MSI:
> +		if (IS_ENABLED(CONFIG_PCI_MSI))
> +			break;
> +		fallthrough;
> +	default:
> +		return -ENOSPC;
> +	}
> +
> +	/* Let a failed PCI multi MSI allocation retry */
> +	if (desc->nvec_used > 1)
> +		return 1;
> +
> +	/* If there was a successful allocation let the caller know */
> +	return allocated ? allocated : -ENOSPC;
> +}
> +
>  int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
>  			    int nvec)
>  {
> @@ -546,6 +567,7 @@ int __msi_domain_alloc_irqs(struct irq_d
>  	struct irq_data *irq_data;
>  	struct msi_desc *desc;
>  	msi_alloc_info_t arg = { };
> +	int allocated = 0;
>  	int i, ret, virq;
>  	bool can_reserve;
>  
> @@ -560,16 +582,15 @@ int __msi_domain_alloc_irqs(struct irq_d
>  					       dev_to_node(dev), &arg, false,
>  					       desc->affinity);
>  		if (virq < 0) {
> -			ret = -ENOSPC;
> -			if (ops->handle_error)
> -				ret = ops->handle_error(domain, desc, ret);
> -			return ret;
> +			ret = msi_handle_pci_fail(domain, desc, allocated);
> +			goto cleanup;
>  		}
>  
>  		for (i = 0; i < desc->nvec_used; i++) {
>  			irq_set_msi_desc_off(virq, i, desc);
>  			irq_debugfs_copy_devname(virq + i, dev);
>  		}
> +		allocated++;
>  	}
>  
>  	can_reserve = msi_check_reservation_mode(domain, info, dev);
>
diff mbox series

Patch

--- a/drivers/pci/msi/irqdomain.c
+++ b/drivers/pci/msi/irqdomain.c
@@ -95,16 +95,6 @@  static int pci_msi_domain_check_cap(stru
 	return 0;
 }
 
-static int pci_msi_domain_handle_error(struct irq_domain *domain,
-				       struct msi_desc *desc, int error)
-{
-	/* Special handling to support __pci_enable_msi_range() */
-	if (pci_msi_desc_is_multi_msi(desc) && error == -ENOSPC)
-		return 1;
-
-	return error;
-}
-
 static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
 				    struct msi_desc *desc)
 {
@@ -115,7 +105,6 @@  static void pci_msi_domain_set_desc(msi_
 static struct msi_domain_ops pci_msi_domain_ops_default = {
 	.set_desc	= pci_msi_domain_set_desc,
 	.msi_check	= pci_msi_domain_check_cap,
-	.handle_error	= pci_msi_domain_handle_error,
 };
 
 static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
@@ -129,8 +118,6 @@  static void pci_msi_domain_update_dom_op
 			ops->set_desc = pci_msi_domain_set_desc;
 		if (ops->msi_check == NULL)
 			ops->msi_check = pci_msi_domain_check_cap;
-		if (ops->handle_error == NULL)
-			ops->handle_error = pci_msi_domain_handle_error;
 	}
 }
 
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -286,7 +286,6 @@  struct msi_domain_info;
  * @msi_check:		Callback for verification of the domain/info/dev data
  * @msi_prepare:	Prepare the allocation of the interrupts in the domain
  * @set_desc:		Set the msi descriptor for an interrupt
- * @handle_error:	Optional error handler if the allocation fails
  * @domain_alloc_irqs:	Optional function to override the default allocation
  *			function.
  * @domain_free_irqs:	Optional function to override the default free
@@ -295,7 +294,7 @@  struct msi_domain_info;
  * @get_hwirq, @msi_init and @msi_free are callbacks used by the underlying
  * irqdomain.
  *
- * @msi_check, @msi_prepare, @handle_error and @set_desc are callbacks used by
+ * @msi_check, @msi_prepare and @set_desc are callbacks used by
  * msi_domain_alloc/free_irqs().
  *
  * @domain_alloc_irqs, @domain_free_irqs can be used to override the
@@ -332,8 +331,6 @@  struct msi_domain_ops {
 				       msi_alloc_info_t *arg);
 	void		(*set_desc)(msi_alloc_info_t *arg,
 				    struct msi_desc *desc);
-	int		(*handle_error)(struct irq_domain *domain,
-					struct msi_desc *desc, int error);
 	int		(*domain_alloc_irqs)(struct irq_domain *domain,
 					     struct device *dev, int nvec);
 	void		(*domain_free_irqs)(struct irq_domain *domain,
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -538,6 +538,27 @@  static bool msi_check_reservation_mode(s
 	return desc->pci.msi_attrib.is_msix || desc->pci.msi_attrib.can_mask;
 }
 
+static int msi_handle_pci_fail(struct irq_domain *domain, struct msi_desc *desc,
+			       int allocated)
+{
+	switch(domain->bus_token) {
+	case DOMAIN_BUS_PCI_MSI:
+	case DOMAIN_BUS_VMD_MSI:
+		if (IS_ENABLED(CONFIG_PCI_MSI))
+			break;
+		fallthrough;
+	default:
+		return -ENOSPC;
+	}
+
+	/* Let a failed PCI multi MSI allocation retry */
+	if (desc->nvec_used > 1)
+		return 1;
+
+	/* If there was a successful allocation let the caller know */
+	return allocated ? allocated : -ENOSPC;
+}
+
 int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
 			    int nvec)
 {
@@ -546,6 +567,7 @@  int __msi_domain_alloc_irqs(struct irq_d
 	struct irq_data *irq_data;
 	struct msi_desc *desc;
 	msi_alloc_info_t arg = { };
+	int allocated = 0;
 	int i, ret, virq;
 	bool can_reserve;
 
@@ -560,16 +582,15 @@  int __msi_domain_alloc_irqs(struct irq_d
 					       dev_to_node(dev), &arg, false,
 					       desc->affinity);
 		if (virq < 0) {
-			ret = -ENOSPC;
-			if (ops->handle_error)
-				ret = ops->handle_error(domain, desc, ret);
-			return ret;
+			ret = msi_handle_pci_fail(domain, desc, allocated);
+			goto cleanup;
 		}
 
 		for (i = 0; i < desc->nvec_used; i++) {
 			irq_set_msi_desc_off(virq, i, desc);
 			irq_debugfs_copy_devname(virq + i, dev);
 		}
+		allocated++;
 	}
 
 	can_reserve = msi_check_reservation_mode(domain, info, dev);