* which are relevant to both the kernel and user-mode software.
*/
-/*
- * Virtual memory map: Permissions
- * kernel/user
- *
- * 4 Gig --------> +------------------------------+
- * | | RW/--
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- * : . :
- * : . :
- * : . :
- * |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| RW/--
- * | | RW/--
- * | Remapped Physical Memory | RW/--
- * | | RW/--
- * KERNBASE -----> +------------------------------+ 0xc0000000
- * | Cur. Page Table (Kern. RW) | RW/-- PTSIZE
- * VPT,KSTACKTOP--> +------------------------------+ 0xbfc00000 --+
- * | Kernel Stack | RW/-- KSTKSIZE |
- * | - - - - - - - - - - - - - - -| PTSIZE
- * | Invalid Memory (*) | --/-- |
- * ULIM ----> +------------------------------+ 0xbf800000 --+
- * | Cur. Page Table (User R-) | R-/R- PTSIZE
- * UVPT ----> +------------------------------+ 0xbf400000 --+
- * | Unmapped (expandable region) | |
- * | | R-/R- PTSIZE
- * | Per-Process R/O Info | |
- * UTOP, UINFO ----> +------------------------------+ 0xbf000000 --+
- * | Unmapped (expandable region) | |
- * | | RW/RW PTSIZE
- * | Per-Process R/W Data | |
- * UDATA ----> +------------------------------+ 0xbec00000 --+
- * | Global Shared R/W Data | RW/RW PGSIZE
- * UXSTACKTOP,UGDATA ->+------------------------------+ 0xbebff000
- * | User Exception Stack | RW/RW PGSIZE
- * +------------------------------+ 0xbebfe000
- * | Empty Memory (*) | --/-- PGSIZE
- * USTACKTOP ---> +------------------------------+ 0xbebfd000
- * | Normal User Stack | RW/RW 256*PGSIZE (1MB)
- * +------------------------------+ 0xbeafd000
- * | Empty Memory (*) | --/-- PGSIZE
- * USTACKBOT ---> +------------------------------+ 0xbeafc000
- * | |
- * | |
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- * . .
- * . .
- * . .
- * |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~|
- * | Program Data & Heap |
- * UTEXT --------> +------------------------------+ 0x00800000
- * PFTEMP -------> | Empty Memory (*) | PTSIZE
- * | |
- * UTEMP --------> +------------------------------+ 0x00400000 --+
- * | Empty Memory (*) | |
- * | - - - - - - - - - - - - - - -| |
- * | User STAB Data (optional) | PTSIZE
- * USTABDATA ----> +------------------------------+ 0x00200000 |
- * | Empty Memory (*) | |
- * 0 ------------> +------------------------------+ --+
- *
- * (*) Note: The kernel ensures that "Invalid Memory" (ULIM) is *never*
- * mapped. "Empty Memory" is normally unmapped, but user programs may
- * map pages there if desired. ROS user programs map pages temporarily
- * at UTEMP.
- */
-
-
-// At IOPHYSMEM (640K) there is a 384K hole for I/O. From the kernel,
-// IOPHYSMEM can be addressed at KERNBASE + IOPHYSMEM. The hole ends
-// at physical address EXTPHYSMEM.
-#define IOPHYSMEM 0x0A0000
-#define VGAPHYSMEM 0x0A0000
-#define DEVPHYSMEM 0x0C0000
-#define BIOSPHYSMEM 0x0F0000
+/* TODO: sort out multiboot being in src/ (depends on this) */
+#ifndef EXTPHYSMEM
#define EXTPHYSMEM 0x100000
-
-// Virtual page table. Entry PDX(VPT) in the PD contains a pointer to
-// the page directory itself, thereby turning the PD into a page table,
-// which maps all the PTEs containing the page mappings for the entire
-// virtual address space into that 4 Meg region starting at VPT.
-#define VPT (KERNBASE - PTSIZE)
-#define KSTACKTOP VPT
-#define KSTKSHIFT (PGSHIFT+3) // KSTKSIZE == 8*PGSIZE
-#define KSTKSIZE (1 << KSTKSHIFT) // size of a kernel stack
-#define ULIM (KSTACKTOP - PTSIZE)
-
-/*
- * User read-only mappings! Anything below here til UTOP are readonly to user.
- * They are global pages mapped in at env allocation time.
- */
-
-// Same as VPT but read-only for users
-#define UVPT (ULIM - PTSIZE)
-
-/*
- * Top of user VM. User can manipulate VA from UTOP-1 and down!
- */
-
-// Top of user-accessible VM
-#define UTOP (UVPT - PTSIZE)
-// Read-only, per-process shared info structures
-#define UINFO UTOP
-
-// Read-write, per-process shared page for sending asynchronous
-// syscalls to the kernel
-#define UDATA (UTOP - PTSIZE)
-
-// Read-write, global page. Shared by all processes. Can't be trusted.
-#define UGDATA (UDATA - PGSIZE)
-
-// Top of one-page user exception stack
-#define UXSTACKTOP UGDATA
-// Next page left invalid to guard against exception stack overflow; then:
-// Top of normal user stack
-#define USTACKTOP (UXSTACKTOP - 2*PGSIZE)
-// Maximum stack depth preallocated to 1MB
-#define USTACK_NUM_PAGES 256
-// Next page left invalid to guard against stack overflow
-// Maximum bottom of normal user stack
-#define USTACKBOT (USTACKTOP - (USTACK_NUM_PAGES+1)*PGSIZE)
-
-// Arbitrary boundary between the break and the start of
-// memory returned by calls to mmap with addr = 0
-#define BRK_END 0x20000000
-
-// Where user programs generally begin
-#define UTEXT (2*PTSIZE)
-
-// Used for temporary page mappings. Typed 'void*' for convenience
-#define UTEMP ((void*) PTSIZE)
-// Used for temporary page mappings for the user page-fault handler
-// (should not conflict with other temporary page mappings)
-#define PFTEMP (UTEMP + PTSIZE - PGSIZE)
-// The location of the user-level STABS data structure
-#define USTABDATA (PTSIZE / 2)
-
-
-#ifndef __ASSEMBLER__
-
-/*
- * The page directory entry corresponding to the virtual address range
- * [VPT, VPT + PTSIZE) points to the page directory itself. Thus, the page
- * directory is treated as a page table as well as a page directory.
- *
- * One result of treating the page directory as a page table is that all PTEs
- * can be accessed through a "virtual page table" at virtual address VPT (to
- * which vpt is set in entry.S). The PTE for page number N is stored in
- * vpt[N]. (It's worth drawing a diagram of this!)
- *
- * A second consequence is that the contents of the current page directory
- * will always be available at virtual address (VPT + (VPT >> PGSHIFT)), to
- * which vpd is set in entry.S.
- */
-
-#ifdef __IVY__
-#pragma cilnoremove("vpt_lock", "vpd_lock")
#endif
-extern volatile uint32_t vpt_lock;
-extern volatile uint32_t vpd_lock;
-extern volatile pte_t SLOCKED(&vpt_lock) (COUNT(PTSIZE) SREADONLY vpt)[]; // VA of "virtual page table"
-extern volatile pde_t SLOCKED(&vpd_lock) (COUNT(PTSIZE) SREADONLY vpd)[]; // VA of current page directory
+#define KSTKSHIFT (PGSHIFT) /* KSTKSIZE == PGSIZE */
+#define KSTKSIZE (1 << KSTKSHIFT) /* size of a static kernel stack */
+
+/* Read-only, per-process shared info structures */
+#define UINFO (UVPT - PTSIZE)
+/* Top of user-writable VM */
+#define UWLIM UINFO
+/* Read-write, per-process shared info structures */
+#define UDATA (UWLIM - PTSIZE)
+/* Read-write, global page. Shared by all processes. */
+#define UGDATA (UDATA - PGSIZE)
+/* Limit of what is mmap()/munmap()-able */
+#define UMAPTOP UGDATA
+/* Top of normal user stack */
+#define USTACKTOP UMAPTOP
+/* Stack size of thread0, allocated by the kernel */
+#define USTACK_NUM_PAGES 256
-#endif /* !__ASSEMBLER__ */
#endif /* !ROS_INC_MEMLAYOUT_H */
projects / akaros.git / blobdiff