genirq/msi: Add cpumask allocation to alloc_msi_entry

For irq spreading want to store affinity masks in the msi_entry. Add the
infrastructure for it.

We allocate an array of cpumasks with an array size of the number of used
vectors in the entry, so we can hand in the information per linux interrupt
later.

As we hand in the number of used vectors, we assign them right
away. Convert all the call sites.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/1473862739-15032-2-git-send-email-hch@lst.de

1 files changed, 24 insertions, 2 deletions

diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 19e9dfb..8a3e8727 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -18,20 +18,42 @@
 /* Temparory solution for building, will be removed later */
 #include <linux/pci.h>
 
-struct msi_desc *alloc_msi_entry(struct device *dev)
+/**
+ * alloc_msi_entry - Allocate an initialize msi_entry
+ * @dev:	Pointer to the device for which this is allocated
+ * @nvec:	The number of vectors used in this entry
+ * @affinity:	Optional pointer to an affinity mask array size of @nvec
+ *
+ * If @affinity is not NULL then a an affinity array[@nvec] is allocated
+ * and the affinity masks from @affinity are copied.
+ */
+struct msi_desc *
+alloc_msi_entry(struct device *dev, int nvec, const struct cpumask *affinity)
 {
-	struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+	struct msi_desc *desc;
+
+	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 	if (!desc)
 		return NULL;
 
 	INIT_LIST_HEAD(&desc->list);
 	desc->dev = dev;
+	desc->nvec_used = nvec;
+	if (affinity) {
+		desc->affinity = kmemdup(affinity,
+			nvec * sizeof(*desc->affinity), GFP_KERNEL);
+		if (!desc->affinity) {
+			kfree(desc);
+			return NULL;
+		}
+	}
 
 	return desc;
 }
 
 void free_msi_entry(struct msi_desc *entry)
 {
+	kfree(entry->affinity);
 	kfree(entry);
 }