Commit 059c1893 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/64e: Reorganise virtual memory 



Reduce the size of IO map in order to leave the last
quarter of virtual MAP for KASAN shadow mapping.

This gives the following layout.

   +------------------------+  Kernel virtual map end (0xc000200000000000)
   |                        |
   |    16TB (unused)       |
   |                        |
   +------------------------+  Kernel IO map end
   |                        |
   |    16TB of IO map      |
   |                        |
   +------------------------+  Kernel IO map start
   |                        |
   |    16TB of vmemmap     |
   |                        |
   +------------------------+  Kernel vmemmap start
   |                        |
   |    16TB of vmap        |
   |                        |
   +------------------------+  Kernel virt start (0xc000100000000000)
   |                        |
   |    64TB of linear mem  |
   |                        |
   +------------------------+  Kernel linear (0xc.....)

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/54ef01673bf14228106afd629f795c83acb9a00c.1656427701.git.christophe.leroy@csgroup.eu
parent 128c1ea2

arch/powerpc/include/asm/nohash/64/pgtable.h

+4 −3
Original line number Diff line number Diff line
@@ -38,15 +38,16 @@ 
#define VMALLOC_END	(VMALLOC_START + VMALLOC_SIZE)



/*

 * The second half of the kernel virtual space is used for IO mappings,

 * The third quarter of the kernel virtual space is used for IO mappings,

 * it's itself carved into the PIO region (ISA and PHB IO space) and

 * the ioremap space

 *

 *  ISA_IO_BASE = KERN_IO_START, 64K reserved area

 *  PHB_IO_BASE = ISA_IO_BASE + 64K to ISA_IO_BASE + 2G, PHB IO spaces

 * IOREMAP_BASE = ISA_IO_BASE + 2G to VMALLOC_START + PGTABLE_RANGE

 * IOREMAP_BASE = ISA_IO_BASE + 2G to KERN_IO_START + KERN_IO_SIZE

 */

#define KERN_IO_START	(KERN_VIRT_START + (KERN_VIRT_SIZE >> 1))

#define KERN_IO_SIZE	(KERN_VIRT_SIZE >> 2)

#define FULL_IO_SIZE	0x80000000ul

#define  ISA_IO_BASE	(KERN_IO_START)

#define  ISA_IO_END	(KERN_IO_START + 0x10000ul)
@@ -54,7 +55,7 @@ 
#define  PHB_IO_END	(KERN_IO_START + FULL_IO_SIZE)

#define IOREMAP_BASE	(PHB_IO_END)

#define IOREMAP_START	(ioremap_bot)

#define IOREMAP_END	(KERN_VIRT_START + KERN_VIRT_SIZE - FIXADDR_SIZE)

#define IOREMAP_END	(KERN_IO_START + KERN_IO_SIZE - FIXADDR_SIZE)

#define FIXADDR_SIZE	SZ_32M



/*