From 7e84a88243b57bc90d1ef6bd42661f499886e659 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 12 Jun 2023 09:57:18 +0200 Subject: [PATCH] xen/pci: add flag for PCI passthrough being possible When running as a Xen PV guests passed through PCI devices only have a chance to work if the Xen supplied memory map has some PCI space reserved. Add a flag xen_pv_pci_possible which will be set in early boot in case the memory map has at least one area with the type E820_TYPE_RESERVED. Signed-off-by: Juergen Gross --- arch/x86/xen/setup.c | 6 ++++++ include/xen/xen.h | 6 ++++++ 2 files changed, 12 insertions(+) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index c2be3efb2ba0..716f76c41416 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -43,6 +43,9 @@ struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; /* Number of pages released from the initial allocation. */ unsigned long xen_released_pages; +/* Memory map would allow PCI passthrough. */ +bool xen_pv_pci_possible; + /* E820 map used during setting up memory. */ static struct e820_table xen_e820_table __initdata; @@ -804,6 +807,9 @@ char * __init xen_memory_setup(void) chunk_size = size; type = xen_e820_table.entries[i].type; + if (type == E820_TYPE_RESERVED) + xen_pv_pci_possible = true; + if (type == E820_TYPE_RAM) { if (addr < mem_end) { chunk_size = min(size, mem_end - addr); diff --git a/include/xen/xen.h b/include/xen/xen.h index 0efeb652f9b8..5eb0a974a11e 100644 --- a/include/xen/xen.h +++ b/include/xen/xen.h @@ -29,6 +29,12 @@ extern bool xen_pvh; extern uint32_t xen_start_flags; +#ifdef CONFIG_XEN_PV +extern bool xen_pv_pci_possible; +#else +#define xen_pv_pci_possible 0 +#endif + #include extern struct hvm_start_info pvh_start_info; -- 2.35.3