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-rw-r--r--src/threads/intr-stubs.S204
1 files changed, 204 insertions, 0 deletions
diff --git a/src/threads/intr-stubs.S b/src/threads/intr-stubs.S
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+++ b/src/threads/intr-stubs.S
@@ -0,0 +1,204 @@
+#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)
generated by cgit v1.2.1 (git 2.18.0) at 2025-12-13 23:35:25 +0100