#include "threads/loader.h" .text /* Main interrupt entry point. An internal or external interrupt starts in one of the intrNN_stub routines, which push the `struct intr_frame' frame_pointer, error_code, and vec_no members on the stack, then jump here. We save the rest of the `struct intr_frame' members to the stack, set up some registers as needed by the kernel, and then call intr_handler(), which actually handles the interrupt. We "fall through" to intr_exit to return from the interrupt. */ .func intr_entry intr_entry: /* Save caller's registers. */ pushl %ds pushl %es pushl %fs pushl %gs pushal /* Set up kernel environment. */ cld /* String instructions go upward. */ mov $SEL_KDSEG, %eax /* Initialize segment registers. */ mov %eax, %ds mov %eax, %es leal 56(%esp), %ebp /* Set up frame pointer. */ /* Call interrupt handler. */ pushl %esp .globl intr_handler call intr_handler addl $4, %esp .endfunc /* Interrupt exit. Restores the caller's registers, discards extra data on the stack, and returns to the caller. This is a separate function because it is called directly when we launch a new user process (see start_process() in userprog/process.c). */ .globl intr_exit .func intr_exit intr_exit: /* Restore caller's registers. */ popal popl %gs popl %fs popl %es popl %ds /* Discard `struct intr_frame' vec_no, error_code, frame_pointer members. */ addl $12, %esp /* Return to caller. */ iret .endfunc /* Interrupt stubs. This defines 256 fragments of code, named `intr00_stub' through `intrff_stub', each of which is used as the entry point for the corresponding interrupt vector. It also puts the address of each of these functions in the correct spot in `intr_stubs', an array of function pointers. Most of the stubs do this: 1. Push %ebp on the stack (frame_pointer in `struct intr_frame'). 2. Push 0 on the stack (error_code). 3. Push the interrupt number on the stack (vec_no). The CPU pushes an extra "error code" on the stack for a few interrupts. Because we want %ebp to be where the error code is, we follow a different path: 1. Push a duplicate copy of the error code on the stack. 2. Replace the original copy of the error code by %ebp. 3. Push the interrupt number on the stack. */ .data .globl intr_stubs intr_stubs: /* This implements steps 1 and 2, described above, in the common case where we just push a 0 error code. */ #define zero \ pushl %ebp; \ pushl $0 /* This implements steps 1 and 2, described above, in the case where the CPU already pushed an error code. */ #define REAL \ pushl (%esp); \ movl %ebp, 4(%esp) /* Emits a stub for interrupt vector NUMBER. TYPE is `zero', for the case where we push a 0 error code, or `REAL', if the CPU pushes an error code for us. */ #define STUB(NUMBER, TYPE) \ .text; \ .globl intr##NUMBER##_stub; \ .func intr##NUMBER##_stub; \ intr##NUMBER##_stub: \ TYPE; \ push $0x##NUMBER; \ jmp intr_entry; \ .endfunc; \ \ .data; \ .long intr##NUMBER##_stub; /* All the stubs. */ STUB(00, zero) STUB(01, zero) STUB(02, zero) STUB(03, zero) STUB(04, zero) STUB(05, zero) STUB(06, zero) STUB(07, zero) STUB(08, REAL) STUB(09, zero) STUB(0a, REAL) STUB(0b, REAL) STUB(0c, zero) STUB(0d, REAL) STUB(0e, REAL) STUB(0f, zero) STUB(10, zero) STUB(11, REAL) STUB(12, zero) STUB(13, zero) STUB(14, zero) STUB(15, zero) STUB(16, zero) STUB(17, zero) STUB(18, REAL) STUB(19, zero) STUB(1a, REAL) STUB(1b, REAL) STUB(1c, zero) STUB(1d, REAL) STUB(1e, REAL) STUB(1f, zero) STUB(20, zero) STUB(21, zero) STUB(22, zero) STUB(23, zero) STUB(24, zero) STUB(25, zero) STUB(26, zero) STUB(27, zero) STUB(28, zero) STUB(29, zero) STUB(2a, zero) STUB(2b, zero) STUB(2c, zero) STUB(2d, zero) STUB(2e, zero) STUB(2f, zero) STUB(30, zero) STUB(31, zero) STUB(32, zero) STUB(33, zero) STUB(34, zero) STUB(35, zero) STUB(36, zero) STUB(37, zero) STUB(38, zero) STUB(39, zero) STUB(3a, zero) STUB(3b, zero) STUB(3c, zero) STUB(3d, zero) STUB(3e, zero) STUB(3f, zero) STUB(40, zero) STUB(41, zero) STUB(42, zero) STUB(43, zero) STUB(44, zero) STUB(45, zero) STUB(46, zero) STUB(47, zero) STUB(48, zero) STUB(49, zero) STUB(4a, zero) STUB(4b, zero) STUB(4c, zero) STUB(4d, zero) STUB(4e, zero) STUB(4f, zero) STUB(50, zero) STUB(51, zero) STUB(52, zero) STUB(53, zero) STUB(54, zero) STUB(55, zero) STUB(56, zero) STUB(57, zero) STUB(58, zero) STUB(59, zero) STUB(5a, zero) STUB(5b, zero) STUB(5c, zero) STUB(5d, zero) STUB(5e, zero) STUB(5f, zero) STUB(60, zero) STUB(61, zero) STUB(62, zero) STUB(63, zero) STUB(64, zero) STUB(65, zero) STUB(66, zero) STUB(67, zero) STUB(68, zero) STUB(69, zero) STUB(6a, zero) STUB(6b, zero) STUB(6c, zero) STUB(6d, zero) STUB(6e, zero) STUB(6f, zero) STUB(70, zero) STUB(71, zero) STUB(72, zero) STUB(73, zero) STUB(74, zero) STUB(75, zero) STUB(76, zero) STUB(77, zero) STUB(78, zero) STUB(79, zero) STUB(7a, zero) STUB(7b, zero) STUB(7c, zero) STUB(7d, zero) STUB(7e, zero) STUB(7f, zero) STUB(80, zero) STUB(81, zero) STUB(82, zero) STUB(83, zero) STUB(84, zero) STUB(85, zero) STUB(86, zero) STUB(87, zero) STUB(88, zero) STUB(89, zero) STUB(8a, zero) STUB(8b, zero) STUB(8c, zero) STUB(8d, zero) STUB(8e, zero) STUB(8f, zero) STUB(90, zero) STUB(91, zero) STUB(92, zero) STUB(93, zero) STUB(94, zero) STUB(95, zero) STUB(96, zero) STUB(97, zero) STUB(98, zero) STUB(99, zero) STUB(9a, zero) STUB(9b, zero) STUB(9c, zero) STUB(9d, zero) STUB(9e, zero) STUB(9f, zero) STUB(a0, zero) STUB(a1, zero) STUB(a2, zero) STUB(a3, zero) STUB(a4, zero) STUB(a5, zero) STUB(a6, zero) STUB(a7, zero) STUB(a8, zero) STUB(a9, zero) STUB(aa, zero) STUB(ab, zero) STUB(ac, zero) STUB(ad, zero) STUB(ae, zero) STUB(af, zero) STUB(b0, zero) STUB(b1, zero) STUB(b2, zero) STUB(b3, zero) STUB(b4, zero) STUB(b5, zero) STUB(b6, zero) STUB(b7, zero) STUB(b8, zero) STUB(b9, zero) STUB(ba, zero) STUB(bb, zero) STUB(bc, zero) STUB(bd, zero) STUB(be, zero) STUB(bf, zero) STUB(c0, zero) STUB(c1, zero) STUB(c2, zero) STUB(c3, zero) STUB(c4, zero) STUB(c5, zero) STUB(c6, zero) STUB(c7, zero) STUB(c8, zero) STUB(c9, zero) STUB(ca, zero) STUB(cb, zero) STUB(cc, zero) STUB(cd, zero) STUB(ce, zero) STUB(cf, zero) STUB(d0, zero) STUB(d1, zero) STUB(d2, zero) STUB(d3, zero) STUB(d4, zero) STUB(d5, zero) STUB(d6, zero) STUB(d7, zero) STUB(d8, zero) STUB(d9, zero) STUB(da, zero) STUB(db, zero) STUB(dc, zero) STUB(dd, zero) STUB(de, zero) STUB(df, zero) STUB(e0, zero) STUB(e1, zero) STUB(e2, zero) STUB(e3, zero) STUB(e4, zero) STUB(e5, zero) STUB(e6, zero) STUB(e7, zero) STUB(e8, zero) STUB(e9, zero) STUB(ea, zero) STUB(eb, zero) STUB(ec, zero) STUB(ed, zero) STUB(ee, zero) STUB(ef, zero) STUB(f0, zero) STUB(f1, zero) STUB(f2, zero) STUB(f3, zero) STUB(f4, zero) STUB(f5, zero) STUB(f6, zero) STUB(f7, zero) STUB(f8, zero) STUB(f9, zero) STUB(fa, zero) STUB(fb, zero) STUB(fc, zero) STUB(fd, zero) STUB(fe, zero) STUB(ff, zero)