[patch 22/39] PCI/MSI: Move pci_alloc_irq_vectors() to api.c

Thomas Gleixner
2022-11-11T13:56:48Z

From: Ahmed S. Darwish <darwi@linutronix.de>

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

Make pci_alloc_irq_vectors() a real function instead of wrapper and add
proper kernel doc to it.

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
drivers/pci/msi/api.c | 33 +++++++++++++++++++++++++++++++++
include/linux/pci.h | 17 +++++++++--------
2 files changed, 42 insertions(+), 8 deletions(-)
---
diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index d48050555d55..1714905943fb 100644
--- a/drivers/pci/msi/api.c
+++ b/drivers/pci/msi/api.c
@@ -90,3 +90,36 @@ int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries,
return __pci_enable_msix_range(dev, entries, minvec, maxvec, NULL, 0);
}
EXPORT_SYMBOL(pci_enable_msix_range);
+
+/**
+ * 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)
+ * @max_vecs: maximum desired number of vectors
+ * @flags: One or more of:
+ * %PCI_IRQ_MSIX Allow trying MSI-X vector allocations
+ * %PCI_IRQ_MSI Allow trying MSI vector allocations
+ * %PCI_IRQ_LEGACY Allow trying legacy INTx interrupts, if
+ * and only if @min_vecs == 1
+ * %PCI_IRQ_AFFINITY Auto-manage IRQs affinity by spreading
+ * the vectors around available CPUs
+ *
+ * Allocate up to @max_vecs interrupt vectors on device. MSI-X irq
+ * vector allocation has a higher precedence over plain MSI, which has a
+ * higher precedence over legacy INTx emulation.
+ *
+ * Upon a successful allocation, the caller should use pci_irq_vector()
+ * to get the Linux IRQ number to be passed to request_threaded_irq().
+ * The driver must call pci_free_irq_vectors() on cleanup.
+ *
+ * Return: number of allocated vectors (which might be smaller than
+ * @max_vecs), -ENOSPC if less than @min_vecs interrupt vectors are
+ * available, other errnos otherwise.
+ */
+int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
+ unsigned int max_vecs, unsigned int flags)
+{
+ return pci_alloc_irq_vectors_affinity(dev, min_vecs, max_vecs,
+ flags, NULL);
+}
+EXPORT_SYMBOL(pci_alloc_irq_vectors);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 2bda4a4e47e8..6a356a39ba94 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1553,6 +1553,8 @@ static inline int pci_enable_msix_exact(struct pci_dev *dev,
return rc;
return 0;
}
+int pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
+ unsigned int max_vecs, unsigned int flags);
int pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
unsigned int max_vecs, unsigned int flags,
struct irq_affinity *affd);
@@ -1586,6 +1588,13 @@ pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
return 1;
return -ENOSPC;
}
+static inline int
+pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
+ unsigned int max_vecs, unsigned int flags)
+{
+ return pci_alloc_irq_vectors_affinity(dev, min_vecs, max_vecs,
+ flags, NULL);
+}

static inline void pci_free_irq_vectors(struct pci_dev *dev)
{
@@ -1900,14 +1909,6 @@ pci_alloc_irq_vectors_affinity(struct pci_dev *dev, unsigned int min_vecs,
}
#endif /* CONFIG_PCI */

-static inline int
-pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
- unsigned int max_vecs, unsigned int flags)
-{
- return pci_alloc_irq_vectors_affinity(dev, min_vecs, max_vecs, flags,
- NULL);
-}
-
/* Include architecture-dependent settings and functions */

#include <asm/pci.h>