K1OM address space sizes and offsets. More...

Macros
#define	K1OM_VADDR_SPACE_BITS 48

#define	X1OM_PADDR_SPACE_BITS 40

#define	K1OM_START_KERNEL_PHYS 0x100000

#define	K1OM_KERNEL_STACK_SIZE 0x4000

#define	K1OM_PADDR_SPACE_LIMIT ((genpaddr_t)1 << 40)

#define	K1OM_PHYSICAL_MEMORY_SIZE ((genpaddr_t)(6ULL10241024*1024))

#define	K1OM_INIT_SPACE_LIMIT (32 * 1024 * 1024)

#define	K1OM_INIT_VBASE 0x200000

#define	K1OM_KERNEL_INIT_MEMORY (1 * 1024 * 1024)

#define	K1OM_PML4_ALIGN(addr) ((addr) & ((genpaddr_t)0x1ffffffUL << 39))

#define	K1OM_MEMORY_OFFSET K1OM_PML4_ALIGN(-K1OM_PADDR_SPACE_LIMIT)

#define	K1OM_REAL_MODE_SEGMENT 0x0600

#define	K1OM_REAL_MODE_OFFSET 0x0000

#define	K1OM_REAL_MODE_LINEAR_OFFSET (K1OM_REAL_MODE_SEGMENT << 4)

#define	X86_64_REAL_MODE_SEGMENT 0x0600

#define	X86_64_REAL_MODE_OFFSET 0x0000

#define	X86_64_REAL_MODE_LINEAR_OFFSET (X86_64_REAL_MODE_SEGMENT << 4)

Variables
uintptr_t	k1om_kernel_stack [K1OM_KERNEL_STACK_SIZE/sizeof(uintptr_t)]
	The kernel stack. More...

Detailed Description

K1OM address space sizes and offsets.

The layout of the K1OM virtual address space can be summarized as follows:

 +----------------------------------------------------+-----------------+
 | User-space                                         | Physical memory |
 | PML4 entries: 0 1 2 3 4 ... 510                    | 511             |
 +----------------------------------------------------+-----------------+

User-space maps user-space programs. Physical memory maps all available physical memory (up to PADDR_SPACE_LIMIT).

This partition is static and can only be changed at compile-time.

Physical memory can grow downwards, towards user-space, although it is expected to stay within PML4 entry 511 for quite some time (one PML4 entry can map 512 GBytes). The rest of the address space can be freely mapped by (possibly multiple) user-space programs.

Macro Definition Documentation

#define K1OM_INIT_SPACE_LIMIT (32 * 1024 * 1024)

Static address space limit for the init user-space domain. The static space is used to map in code and static data of the init module, as well as all loaded multiboot modules. init can freely allocate dynamic memory as soon as it is running. This is 32 MBytes right now.

You should make this constant a multiple of #BASE_PAGE_SIZE * #PTABLE_SIZE or you'll restrict init's static address space unneccessarily. init's lowest segment should also be based at these multiples or it restricts itself.

#define K1OM_INIT_VBASE 0x200000

Base address of init address space in virtual memory. init should start at 4 MByte. The kernel maps in important structures at 2 MByte. This address should be page-table size aligned (i.e. with 4 KByte pages, a page table maps 2 MBytes. Thus, align it to multiples of 2 MBytes).

#define K1OM_KERNEL_INIT_MEMORY (1 * 1024 * 1024)

Initial amount of physical memory to map during bootup. The low 1MByte of memory is always expected to be there and has to be specified here at minimum. If you need more during bootup, increase this value. This value is also the amount of memory you expect to be in the system during bootup, or the kernel will crash!

#define K1OM_KERNEL_STACK_SIZE 0x4000

Kernel stack size – 16KB

#define K1OM_MEMORY_OFFSET K1OM_PML4_ALIGN(-K1OM_PADDR_SPACE_LIMIT)

Absolute offset of mapped physical memory within virtual address space. This occupies one or more (usually one) PML4 slots directly before the kernel. This needs to be aligned to PADDR_SPACE_LIMIT.

Change VSPACE_END in lib/barrelfish if you change this.

#define K1OM_PADDR_SPACE_LIMIT ((genpaddr_t)1 << 40)

Maximum physical address space mappable by the kernel. Adjust this for a bigger physical address space. We set this to 40-bit, i.e. 1024 GBytes.

Xeon Phi Systems Software Developers Guide, 2.1.4:

The Intel® Xeon Phi™ coprocessor supports 40-bit physical address in 64-bit.

#define K1OM_PHYSICAL_MEMORY_SIZE ((genpaddr_t)(6ULL*1024*1024*1024))

Maximum physical address space mappable by the kernel. Adjust this for a bigger physical address space. We set this to 40-bit, i.e. 1024 GBytes.

Xeon Phi Systems Software Developers Guide, 2.1.4:

The Intel® Xeon Phi™ coprocessor supports 40-bit physical address in 64-bit.

#define K1OM_PML4_ALIGN ( addr ) ((addr) & ((genpaddr_t)0x1ffffffUL << 39))

Aligns an address to the nearest PML4 entry by masking out lower 39 bits.

#define K1OM_REAL_MODE_LINEAR_OFFSET (K1OM_REAL_MODE_SEGMENT << 4)

The linear offset of the real-mode segment

#define K1OM_REAL_MODE_OFFSET 0x0000

The real-mode offset has to be 0000!!

#define K1OM_REAL_MODE_SEGMENT 0x0600

The real-mode addressesThe real-mode segment

#define K1OM_START_KERNEL_PHYS 0x100000

Start address of kernel image in physical memory. This is passed to the linker also. The bootloader will load us there.

#define K1OM_VADDR_SPACE_BITS 48

Absolute size of virtual address space. This is 48-bit on x86-64 currently, which equals 256 TBytes and allows for 512 PML4 slots, each of which can map 512 GBytes.

#define X1OM_PADDR_SPACE_BITS 40

Absolute size of physical address space. This is also 40-bit.

Intel Xeon Phi Systems Software Developers Guide, 2.1.4:

The Intel® Xeon Phi™ coprocessor supports 40-bit physical address in 64-bit.

#define X86_64_REAL_MODE_LINEAR_OFFSET (X86_64_REAL_MODE_SEGMENT << 4)

The linear offset of the real-mode segment

#define X86_64_REAL_MODE_OFFSET 0x0000

The real-mode offset has to be 0000!!

#define X86_64_REAL_MODE_SEGMENT 0x0600

The real-mode segment

Variable Documentation

uintptr_t k1om_kernel_stack[K1OM_KERNEL_STACK_SIZE/sizeof(uintptr_t)]

The kernel stack.

This is the one and only kernel stack for a kernel instance.

Macros

Variables

Detailed Description

Macro Definition Documentation

Variable Documentation