Imbus/xv6-riscv-kernel
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remove some unused vm #defines

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fix corner cases with alignment when mapping kernel ELF file
This commit is contained in:
Robert Morris 2010-08-05 16:00:59 -04:00
parent 2cf6b32d4d
commit c99599784e
4 changed files with 28 additions and 66 deletions
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30
mmu.h
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@ -85,32 +85,20 @@ struct segdesc {
// | Page Directory | Page Table | Offset within Page |
// | Index | Index | |
// +----------------+----------------+---------------------+
// \--- PDX(la) --/ \--- PTX(la) --/ \---- PGOFF(la) ----/
// \----------- PPN(la) -----------/
//
// The PDX, PTX, PGOFF, and PPN macros decompose linear addresses as shown.
// To construct a linear address la from PDX(la), PTX(la), and PGOFF(la),
// use PGADDR(PDX(la), PTX(la), PGOFF(la)).
// page number field of address
#define PPN(la) (((uint) (la)) >> PTXSHIFT)
#define VPN(la) PPN(la) // used to index into vpt[]
// \--- PDX(la) --/ \--- PTX(la) --/
// page directory index
#define PDX(la) ((((uint) (la)) >> PDXSHIFT) & 0x3FF)
#define VPD(la) PDX(la) // used to index into vpd[]
// page table index
#define PTX(la) ((((uint) (la)) >> PTXSHIFT) & 0x3FF)
// offset in page
#define PGOFF(la) (((uint) (la)) & 0xFFF)
// construct linear address from indexes and offset
#define PGADDR(d, t, o) ((uint) ((d) << PDXSHIFT | (t) << PTXSHIFT | (o)))
// mapping from physical addresses to virtual addresses is the identity one
// (really linear addresses, but we map linear to physical also directly)
// turn a kernel linear address into a physical address.
// all of the kernel data structures have linear and
// physical addresses that are equal.
#define PADDR(a) ((uint) a)
// Page directory and page table constants.
@ -120,9 +108,6 @@ struct segdesc {
#define PGSIZE 4096 // bytes mapped by a page
#define PGSHIFT 12 // log2(PGSIZE)
#define PTSIZE (PGSIZE*NPTENTRIES) // bytes mapped by a page directory entry
#define PTSHIFT 22 // log2(PTSIZE)
#define PTXSHIFT 12 // offset of PTX in a linear address
#define PDXSHIFT 22 // offset of PDX in a linear address
@ -140,13 +125,6 @@ struct segdesc {
#define PTE_PS 0x080 // Page Size
#define PTE_MBZ 0x180 // Bits must be zero
// The PTE_AVAIL bits aren't used by the kernel or interpreted by the
// hardware, so user processes are allowed to set them arbitrarily.
#define PTE_AVAIL 0xE00 // Available for software use
// Only flags in PTE_USER may be used in system calls.
#define PTE_USER (PTE_AVAIL | PTE_P | PTE_W | PTE_U)
// Address in page table or page directory entry
#define PTE_ADDR(pte) ((uint) (pte) & ~0xFFF)