Commit 031e011d authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Catalin Marinas
Browse files

arm64: mm: Move PCI I/O emulation region above the vmemmap region 



Move the PCI I/O region above the vmemmap region in the kernel's VA
space. This will permit us to reclaim the lower part of the vmemmap
region for vmalloc/vmap allocations when running a 52-bit VA capable
build on a 48-bit VA capable system.

Also, given that PCI_IO_START is derived from VMEMMAP_END, use that
symbolic constant directly in ptdump rather than deriving it from
VMEMMAP_START and VMEMMAP_SIZE, as those definitions will change in
subsequent patches.

Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20231213084024.2367360-10-ardb@google.com


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
parent 54be6c6c

arch/arm64/include/asm/memory.h

+2 −2
Original line number Diff line number Diff line
@@ -49,8 +49,8 @@ 
#define MODULES_VSIZE		(SZ_2G)

#define VMEMMAP_START		(-(UL(1) << (VA_BITS - VMEMMAP_SHIFT)))

#define VMEMMAP_END		(VMEMMAP_START + VMEMMAP_SIZE)

#define PCI_IO_END		(VMEMMAP_START - SZ_8M)

#define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)

#define PCI_IO_START		(VMEMMAP_END + SZ_8M)

#define PCI_IO_END		(PCI_IO_START + PCI_IO_SIZE)

#define FIXADDR_TOP		(VMEMMAP_START - SZ_32M)



#if VA_BITS > 48

arch/arm64/mm/ptdump.c

+2 −2
Original line number Diff line number Diff line
@@ -47,10 +47,10 @@ static struct addr_marker address_markers[] = { 
	{ VMALLOC_END,			"vmalloc() end" },

	{ FIXADDR_TOT_START,		"Fixmap start" },

	{ FIXADDR_TOP,			"Fixmap end" },

	{ VMEMMAP_START,		"vmemmap start" },

	{ VMEMMAP_END,			"vmemmap end" },

	{ PCI_IO_START,			"PCI I/O start" },

	{ PCI_IO_END,			"PCI I/O end" },

	{ VMEMMAP_START,		"vmemmap start" },

	{ VMEMMAP_START + VMEMMAP_SIZE,	"vmemmap end" },

	{ -1,				NULL },

};