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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/vsyscall-sigreturn.S
downloadconfigs-2.6.12-rc2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/i386/kernel/vsyscall-sigreturn.S')
-rw-r--r--arch/i386/kernel/vsyscall-sigreturn.S142
1 files changed, 142 insertions, 0 deletions
diff --git a/arch/i386/kernel/vsyscall-sigreturn.S b/arch/i386/kernel/vsyscall-sigreturn.S
new file mode 100644
index 00000000000..c8fcf75b9be
--- /dev/null
+++ b/arch/i386/kernel/vsyscall-sigreturn.S
@@ -0,0 +1,142 @@
+/*
+ * Common code for the sigreturn entry points on the vsyscall page.
+ * So far this code is the same for both int80 and sysenter versions.
+ * This file is #include'd by vsyscall-*.S to define them after the
+ * vsyscall entry point. The kernel assumes that the addresses of these
+ * routines are constant for all vsyscall implementations.
+ */
+
+#include <asm/unistd.h>
+#include <asm/asm_offsets.h>
+
+
+/* XXX
+ Should these be named "_sigtramp" or something?
+*/
+
+ .text
+ .org __kernel_vsyscall+32
+ .globl __kernel_sigreturn
+ .type __kernel_sigreturn,@function
+__kernel_sigreturn:
+.LSTART_sigreturn:
+ popl %eax /* XXX does this mean it needs unwind info? */
+ movl $__NR_sigreturn, %eax
+ int $0x80
+.LEND_sigreturn:
+ .size __kernel_sigreturn,.-.LSTART_sigreturn
+
+ .balign 32
+ .globl __kernel_rt_sigreturn
+ .type __kernel_rt_sigreturn,@function
+__kernel_rt_sigreturn:
+.LSTART_rt_sigreturn:
+ movl $__NR_rt_sigreturn, %eax
+ int $0x80
+.LEND_rt_sigreturn:
+ .size __kernel_rt_sigreturn,.-.LSTART_rt_sigreturn
+ .previous
+
+ .section .eh_frame,"a",@progbits
+.LSTARTFRAMEDLSI1:
+ .long .LENDCIEDLSI1-.LSTARTCIEDLSI1
+.LSTARTCIEDLSI1:
+ .long 0 /* CIE ID */
+ .byte 1 /* Version number */
+ .string "zR" /* NUL-terminated augmentation string */
+ .uleb128 1 /* Code alignment factor */
+ .sleb128 -4 /* Data alignment factor */
+ .byte 8 /* Return address register column */
+ .uleb128 1 /* Augmentation value length */
+ .byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
+ .byte 0 /* DW_CFA_nop */
+ .align 4
+.LENDCIEDLSI1:
+ .long .LENDFDEDLSI1-.LSTARTFDEDLSI1 /* Length FDE */
+.LSTARTFDEDLSI1:
+ .long .LSTARTFDEDLSI1-.LSTARTFRAMEDLSI1 /* CIE pointer */
+ /* HACK: The dwarf2 unwind routines will subtract 1 from the
+ return address to get an address in the middle of the
+ presumed call instruction. Since we didn't get here via
+ a call, we need to include the nop before the real start
+ to make up for it. */
+ .long .LSTART_sigreturn-1-. /* PC-relative start address */
+ .long .LEND_sigreturn-.LSTART_sigreturn+1
+ .uleb128 0 /* Augmentation */
+ /* What follows are the instructions for the table generation.
+ We record the locations of each register saved. This is
+ complicated by the fact that the "CFA" is always assumed to
+ be the value of the stack pointer in the caller. This means
+ that we must define the CFA of this body of code to be the
+ saved value of the stack pointer in the sigcontext. Which
+ also means that there is no fixed relation to the other
+ saved registers, which means that we must use DW_CFA_expression
+ to compute their addresses. It also means that when we
+ adjust the stack with the popl, we have to do it all over again. */
+
+#define do_cfa_expr(offset) \
+ .byte 0x0f; /* DW_CFA_def_cfa_expression */ \
+ .uleb128 1f-0f; /* length */ \
+0: .byte 0x74; /* DW_OP_breg4 */ \
+ .sleb128 offset; /* offset */ \
+ .byte 0x06; /* DW_OP_deref */ \
+1:
+
+#define do_expr(regno, offset) \
+ .byte 0x10; /* DW_CFA_expression */ \
+ .uleb128 regno; /* regno */ \
+ .uleb128 1f-0f; /* length */ \
+0: .byte 0x74; /* DW_OP_breg4 */ \
+ .sleb128 offset; /* offset */ \
+1:
+
+ do_cfa_expr(SIGCONTEXT_esp+4)
+ do_expr(0, SIGCONTEXT_eax+4)
+ do_expr(1, SIGCONTEXT_ecx+4)
+ do_expr(2, SIGCONTEXT_edx+4)
+ do_expr(3, SIGCONTEXT_ebx+4)
+ do_expr(5, SIGCONTEXT_ebp+4)
+ do_expr(6, SIGCONTEXT_esi+4)
+ do_expr(7, SIGCONTEXT_edi+4)
+ do_expr(8, SIGCONTEXT_eip+4)
+
+ .byte 0x42 /* DW_CFA_advance_loc 2 -- nop; popl eax. */
+
+ do_cfa_expr(SIGCONTEXT_esp)
+ do_expr(0, SIGCONTEXT_eax)
+ do_expr(1, SIGCONTEXT_ecx)
+ do_expr(2, SIGCONTEXT_edx)
+ do_expr(3, SIGCONTEXT_ebx)
+ do_expr(5, SIGCONTEXT_ebp)
+ do_expr(6, SIGCONTEXT_esi)
+ do_expr(7, SIGCONTEXT_edi)
+ do_expr(8, SIGCONTEXT_eip)
+
+ .align 4
+.LENDFDEDLSI1:
+
+ .long .LENDFDEDLSI2-.LSTARTFDEDLSI2 /* Length FDE */
+.LSTARTFDEDLSI2:
+ .long .LSTARTFDEDLSI2-.LSTARTFRAMEDLSI1 /* CIE pointer */
+ /* HACK: See above wrt unwind library assumptions. */
+ .long .LSTART_rt_sigreturn-1-. /* PC-relative start address */
+ .long .LEND_rt_sigreturn-.LSTART_rt_sigreturn+1
+ .uleb128 0 /* Augmentation */
+ /* What follows are the instructions for the table generation.
+ We record the locations of each register saved. This is
+ slightly less complicated than the above, since we don't
+ modify the stack pointer in the process. */
+
+ do_cfa_expr(RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_esp)
+ do_expr(0, RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_eax)
+ do_expr(1, RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_ecx)
+ do_expr(2, RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_edx)
+ do_expr(3, RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_ebx)
+ do_expr(5, RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_ebp)
+ do_expr(6, RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_esi)
+ do_expr(7, RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_edi)
+ do_expr(8, RT_SIGFRAME_sigcontext-4 + SIGCONTEXT_eip)
+
+ .align 4
+.LENDFDEDLSI2:
+ .previous