From b834e3c08fc6c4460c2bce6575cba4705f6301e3 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 25 Nov 2022 00:26:20 +0100 Subject: genirq/msi: Provide MSI_FLAG_MSIX_ALLOC_DYN Provide a new MSI feature flag in preparation for dynamic MSIX allocation after the initial MSI-X enable has been done. This needs to be an explicit MSI interrupt domain feature because quite some implementations (both interrupt domains and legacy allocation mode) have clear expectations that the allocation code is only invoked when MSI-X is about to be enabled. They either talk to hypervisors or do some other work and are not prepared to be invoked on an already MSI-X enabled device. This is also explicit MSI-X only because rewriting the size of the MSI entries is only possible when disabling MSI which in turn might cause lost interrupts on the device. Signed-off-by: Thomas Gleixner Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Acked-by: Marc Zyngier Link: https://lore.kernel.org/r/20221124232326.558843119@linutronix.de --- include/linux/msi.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/msi.h b/include/linux/msi.h index 00c501979ff1..3cb15866ffbf 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -557,7 +557,8 @@ enum { MSI_FLAG_LEVEL_CAPABLE = (1 << 18), /* MSI-X entries must be contiguous */ MSI_FLAG_MSIX_CONTIGUOUS = (1 << 19), - + /* PCI/MSI-X vectors can be dynamically allocated/freed post MSI-X enable */ + MSI_FLAG_PCI_MSIX_ALLOC_DYN = (1 << 20), }; /** -- cgit v1.2.3