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-rw-r--r--kernel.ld59
-rw-r--r--memlayout.h26
2 files changed, 85 insertions, 0 deletions
diff --git a/kernel.ld b/kernel.ld
new file mode 100644
index 0000000..3726f4e
--- /dev/null
+++ b/kernel.ld
@@ -0,0 +1,59 @@
+/* Simple linker script for the JOS kernel.
+ See the GNU ld 'info' manual ("info ld") to learn the syntax. */
+
+OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386")
+OUTPUT_ARCH(i386)
+ENTRY(_start)
+
+SECTIONS
+{
+ /* Load the kernel at this address: "." means the current address */
+ . = 0xF0100000;
+
+ .text : AT(0x100000) {
+ *(.text .stub .text.* .gnu.linkonce.t.*)
+ }
+
+ PROVIDE(etext = .); /* Define the 'etext' symbol to this value */
+
+ .rodata : {
+ *(.rodata .rodata.* .gnu.linkonce.r.*)
+ }
+
+ /* Include debugging information in kernel memory */
+ .stab : {
+ PROVIDE(__STAB_BEGIN__ = .);
+ *(.stab);
+ PROVIDE(__STAB_END__ = .);
+ BYTE(0) /* Force the linker to allocate space
+ for this section */
+ }
+
+ .stabstr : {
+ PROVIDE(__STABSTR_BEGIN__ = .);
+ *(.stabstr);
+ PROVIDE(__STABSTR_END__ = .);
+ BYTE(0) /* Force the linker to allocate space
+ for this section */
+ }
+
+ /* Adjust the address for the data segment to the next page */
+ . = ALIGN(0x1000);
+
+ /* The data segment */
+ .data : {
+ *(.data)
+ }
+
+ PROVIDE(edata = .);
+
+ .bss : {
+ *(.bss)
+ }
+
+ PROVIDE(end = .);
+
+ /DISCARD/ : {
+ *(.eh_frame .note.GNU-stack)
+ }
+}
diff --git a/memlayout.h b/memlayout.h
new file mode 100644
index 0000000..3958062
--- /dev/null
+++ b/memlayout.h
@@ -0,0 +1,26 @@
+// Memory layout
+
+#define PGSIZE 4096 // bytes mapped by a page
+#define PGSHIFT 12 // log2(PGSIZE)
+
+#define KSTKSIZE (8*PGSIZE) // size of a kernel stack
+
+#define IOSPACEB 0x0A0000 // begin IO space
+#define IOSPACEE 0x100000 // end IO space
+#define PHYSTOP 0xE000000 // use phys mem up to here as free pool
+
+// Key addresses for address space layout (see kmap in vm.c for the actual layout)
+#define KERNBASE 0xF0000000 // First kernel virtual address
+#define USERTOP (KERNBASE-PGSIZE) // Highest user virtual address
+#define KERNLINK 0xF0100000 // Address where kernel is linked
+
+#ifndef __ASSEMBLER__
+
+static inline uint v2p(void *a) { return (uint) a - KERNBASE; }
+static inline void *p2v(uint a) { return (void *) a + KERNBASE; }
+
+#endif
+
+#define V2P(a) ((uint) a - KERNBASE)
+#define P2V(a) ((void *) a + KERNBASE)
+