vaddr.h

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#ifndef THREADS_VADDR_H
#define THREADS_VADDR_H
 
#include <debug.h>
#include <stdint.h>
#include <stdbool.h>
 
#include "threads/loader.h"
 
/* Functions and macros for working with virtual addresses.
 *
 * See pte.h for functions and macros specifically for x86
 * hardware page tables. */
 
#define BITMASK(SHIFT, CNT) (((1ul << (CNT)) - 1) << (SHIFT))
 
/* Page offset (bits 0:12). */
#define PGSHIFT 0                          /* Index of first offset bit. */
#define PGBITS  12                         /* Number of offset bits. */
#define PGSIZE  (1 << PGBITS)              /* Bytes in a page. */
#define PGMASK  BITMASK(PGSHIFT, PGBITS)   /* Page offset bits (0:12). */
 
/* Offset within a page. */
#define pg_ofs(va) ((uint64_t) (va) & PGMASK)
 
#define pg_no(va) ((uint64_t) (va) >> PGBITS)
 
/* Round up to nearest page boundary. */
#define pg_round_up(va) ((void *) (((uint64_t) (va) + PGSIZE - 1) & ~PGMASK))
 
/* Round down to nearest page boundary. */
#define pg_round_down(va) (void *) ((uint64_t) (va) & ~PGMASK)
 
/* Kernel virtual address start */
#define KERN_BASE LOADER_KERN_BASE
 
/* User stack start */
#define USER_STACK 0x47480000
 
/* Returns true if VADDR is a user virtual address. */
#define is_user_vaddr(vaddr) (!is_kernel_vaddr((vaddr)))
 
/* Returns true if VADDR is a kernel virtual address. */
#define is_kernel_vaddr(vaddr) ((uint64_t)(vaddr) >= KERN_BASE)
 
// FIXME: add checking
/* Returns kernel virtual address at which physical address PADDR
 *  is mapped. */
#define ptov(paddr) ((void *) (((uint64_t) paddr) + KERN_BASE))
 
/* Returns physical address at which kernel virtual address VADDR
 * is mapped. */
#define vtop(vaddr) \
({ \
    ASSERT(is_kernel_vaddr(vaddr)); \
    ((uint64_t) (vaddr) - (uint64_t) KERN_BASE);\
})
 
#endif /* threads/vaddr.h */