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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/alpha/kernel/entry.S
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/alpha/kernel/entry.S')
-rw-r--r--arch/alpha/kernel/entry.S957
1 files changed, 957 insertions, 0 deletions
diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
new file mode 100644
index 000000000000..f0927ee53f29
--- /dev/null
+++ b/arch/alpha/kernel/entry.S
@@ -0,0 +1,957 @@
+/*
+ * arch/alpha/kernel/entry.S
+ *
+ * Kernel entry-points.
+ */
+
+#include <linux/config.h>
+#include <asm/asm_offsets.h>
+#include <asm/thread_info.h>
+#include <asm/pal.h>
+#include <asm/errno.h>
+#include <asm/unistd.h>
+
+ .text
+ .set noat
+
+/* Stack offsets. */
+#define SP_OFF 184
+#define SWITCH_STACK_SIZE 320
+
+/*
+ * This defines the normal kernel pt-regs layout.
+ *
+ * regs 9-15 preserved by C code
+ * regs 16-18 saved by PAL-code
+ * regs 29-30 saved and set up by PAL-code
+ * JRP - Save regs 16-18 in a special area of the stack, so that
+ * the palcode-provided values are available to the signal handler.
+ */
+
+#define SAVE_ALL \
+ subq $sp, SP_OFF, $sp; \
+ stq $0, 0($sp); \
+ stq $1, 8($sp); \
+ stq $2, 16($sp); \
+ stq $3, 24($sp); \
+ stq $4, 32($sp); \
+ stq $28, 144($sp); \
+ lda $2, alpha_mv; \
+ stq $5, 40($sp); \
+ stq $6, 48($sp); \
+ stq $7, 56($sp); \
+ stq $8, 64($sp); \
+ stq $19, 72($sp); \
+ stq $20, 80($sp); \
+ stq $21, 88($sp); \
+ ldq $2, HAE_CACHE($2); \
+ stq $22, 96($sp); \
+ stq $23, 104($sp); \
+ stq $24, 112($sp); \
+ stq $25, 120($sp); \
+ stq $26, 128($sp); \
+ stq $27, 136($sp); \
+ stq $2, 152($sp); \
+ stq $16, 160($sp); \
+ stq $17, 168($sp); \
+ stq $18, 176($sp)
+
+#define RESTORE_ALL \
+ lda $19, alpha_mv; \
+ ldq $0, 0($sp); \
+ ldq $1, 8($sp); \
+ ldq $2, 16($sp); \
+ ldq $3, 24($sp); \
+ ldq $21, 152($sp); \
+ ldq $20, HAE_CACHE($19); \
+ ldq $4, 32($sp); \
+ ldq $5, 40($sp); \
+ ldq $6, 48($sp); \
+ ldq $7, 56($sp); \
+ subq $20, $21, $20; \
+ ldq $8, 64($sp); \
+ beq $20, 99f; \
+ ldq $20, HAE_REG($19); \
+ stq $21, HAE_CACHE($19); \
+ stq $21, 0($20); \
+ ldq $0, 0($sp); \
+ ldq $1, 8($sp); \
+99:; \
+ ldq $19, 72($sp); \
+ ldq $20, 80($sp); \
+ ldq $21, 88($sp); \
+ ldq $22, 96($sp); \
+ ldq $23, 104($sp); \
+ ldq $24, 112($sp); \
+ ldq $25, 120($sp); \
+ ldq $26, 128($sp); \
+ ldq $27, 136($sp); \
+ ldq $28, 144($sp); \
+ addq $sp, SP_OFF, $sp
+
+/*
+ * Non-syscall kernel entry points.
+ */
+
+ .align 4
+ .globl entInt
+ .ent entInt
+entInt:
+ SAVE_ALL
+ lda $8, 0x3fff
+ lda $26, ret_from_sys_call
+ bic $sp, $8, $8
+ mov $sp, $19
+ jsr $31, do_entInt
+.end entInt
+
+ .align 4
+ .globl entArith
+ .ent entArith
+entArith:
+ SAVE_ALL
+ lda $8, 0x3fff
+ lda $26, ret_from_sys_call
+ bic $sp, $8, $8
+ mov $sp, $18
+ jsr $31, do_entArith
+.end entArith
+
+ .align 4
+ .globl entMM
+ .ent entMM
+entMM:
+ SAVE_ALL
+/* save $9 - $15 so the inline exception code can manipulate them. */
+ subq $sp, 56, $sp
+ stq $9, 0($sp)
+ stq $10, 8($sp)
+ stq $11, 16($sp)
+ stq $12, 24($sp)
+ stq $13, 32($sp)
+ stq $14, 40($sp)
+ stq $15, 48($sp)
+ addq $sp, 56, $19
+/* handle the fault */
+ lda $8, 0x3fff
+ bic $sp, $8, $8
+ jsr $26, do_page_fault
+/* reload the registers after the exception code played. */
+ ldq $9, 0($sp)
+ ldq $10, 8($sp)
+ ldq $11, 16($sp)
+ ldq $12, 24($sp)
+ ldq $13, 32($sp)
+ ldq $14, 40($sp)
+ ldq $15, 48($sp)
+ addq $sp, 56, $sp
+/* finish up the syscall as normal. */
+ br ret_from_sys_call
+.end entMM
+
+ .align 4
+ .globl entIF
+ .ent entIF
+entIF:
+ SAVE_ALL
+ lda $8, 0x3fff
+ lda $26, ret_from_sys_call
+ bic $sp, $8, $8
+ mov $sp, $17
+ jsr $31, do_entIF
+.end entIF
+
+ .align 4
+ .globl entUna
+ .ent entUna
+entUna:
+ lda $sp, -256($sp)
+ stq $0, 0($sp)
+ ldq $0, 256($sp) /* get PS */
+ stq $1, 8($sp)
+ stq $2, 16($sp)
+ stq $3, 24($sp)
+ and $0, 8, $0 /* user mode? */
+ stq $4, 32($sp)
+ bne $0, entUnaUser /* yup -> do user-level unaligned fault */
+ stq $5, 40($sp)
+ stq $6, 48($sp)
+ stq $7, 56($sp)
+ stq $8, 64($sp)
+ stq $9, 72($sp)
+ stq $10, 80($sp)
+ stq $11, 88($sp)
+ stq $12, 96($sp)
+ stq $13, 104($sp)
+ stq $14, 112($sp)
+ stq $15, 120($sp)
+ /* 16-18 PAL-saved */
+ stq $19, 152($sp)
+ stq $20, 160($sp)
+ stq $21, 168($sp)
+ stq $22, 176($sp)
+ stq $23, 184($sp)
+ stq $24, 192($sp)
+ stq $25, 200($sp)
+ stq $26, 208($sp)
+ stq $27, 216($sp)
+ stq $28, 224($sp)
+ stq $gp, 232($sp)
+ lda $8, 0x3fff
+ stq $31, 248($sp)
+ bic $sp, $8, $8
+ jsr $26, do_entUna
+ ldq $0, 0($sp)
+ ldq $1, 8($sp)
+ ldq $2, 16($sp)
+ ldq $3, 24($sp)
+ ldq $4, 32($sp)
+ ldq $5, 40($sp)
+ ldq $6, 48($sp)
+ ldq $7, 56($sp)
+ ldq $8, 64($sp)
+ ldq $9, 72($sp)
+ ldq $10, 80($sp)
+ ldq $11, 88($sp)
+ ldq $12, 96($sp)
+ ldq $13, 104($sp)
+ ldq $14, 112($sp)
+ ldq $15, 120($sp)
+ /* 16-18 PAL-saved */
+ ldq $19, 152($sp)
+ ldq $20, 160($sp)
+ ldq $21, 168($sp)
+ ldq $22, 176($sp)
+ ldq $23, 184($sp)
+ ldq $24, 192($sp)
+ ldq $25, 200($sp)
+ ldq $26, 208($sp)
+ ldq $27, 216($sp)
+ ldq $28, 224($sp)
+ ldq $gp, 232($sp)
+ lda $sp, 256($sp)
+ call_pal PAL_rti
+.end entUna
+
+ .align 4
+ .ent entUnaUser
+entUnaUser:
+ ldq $0, 0($sp) /* restore original $0 */
+ lda $sp, 256($sp) /* pop entUna's stack frame */
+ SAVE_ALL /* setup normal kernel stack */
+ lda $sp, -56($sp)
+ stq $9, 0($sp)
+ stq $10, 8($sp)
+ stq $11, 16($sp)
+ stq $12, 24($sp)
+ stq $13, 32($sp)
+ stq $14, 40($sp)
+ stq $15, 48($sp)
+ lda $8, 0x3fff
+ addq $sp, 56, $19
+ bic $sp, $8, $8
+ jsr $26, do_entUnaUser
+ ldq $9, 0($sp)
+ ldq $10, 8($sp)
+ ldq $11, 16($sp)
+ ldq $12, 24($sp)
+ ldq $13, 32($sp)
+ ldq $14, 40($sp)
+ ldq $15, 48($sp)
+ lda $sp, 56($sp)
+ br ret_from_sys_call
+.end entUnaUser
+
+ .align 4
+ .globl entDbg
+ .ent entDbg
+entDbg:
+ SAVE_ALL
+ lda $8, 0x3fff
+ lda $26, ret_from_sys_call
+ bic $sp, $8, $8
+ mov $sp, $16
+ jsr $31, do_entDbg
+.end entDbg
+
+/*
+ * The system call entry point is special. Most importantly, it looks
+ * like a function call to userspace as far as clobbered registers. We
+ * do preserve the argument registers (for syscall restarts) and $26
+ * (for leaf syscall functions).
+ *
+ * So much for theory. We don't take advantage of this yet.
+ *
+ * Note that a0-a2 are not saved by PALcode as with the other entry points.
+ */
+
+ .align 4
+ .globl entSys
+ .globl ret_from_sys_call
+ .ent entSys
+entSys:
+ SAVE_ALL
+ lda $8, 0x3fff
+ bic $sp, $8, $8
+ lda $4, NR_SYSCALLS($31)
+ stq $16, SP_OFF+24($sp)
+ lda $5, sys_call_table
+ lda $27, sys_ni_syscall
+ cmpult $0, $4, $4
+ ldl $3, TI_FLAGS($8)
+ stq $17, SP_OFF+32($sp)
+ s8addq $0, $5, $5
+ stq $18, SP_OFF+40($sp)
+ blbs $3, strace
+ beq $4, 1f
+ ldq $27, 0($5)
+1: jsr $26, ($27), alpha_ni_syscall
+ ldgp $gp, 0($26)
+ blt $0, $syscall_error /* the call failed */
+ stq $0, 0($sp)
+ stq $31, 72($sp) /* a3=0 => no error */
+
+ .align 4
+ret_from_sys_call:
+ cmovne $26, 0, $19 /* $19 = 0 => non-restartable */
+ ldq $0, SP_OFF($sp)
+ and $0, 8, $0
+ beq $0, restore_all
+ret_from_reschedule:
+ /* Make sure need_resched and sigpending don't change between
+ sampling and the rti. */
+ lda $16, 7
+ call_pal PAL_swpipl
+ ldl $5, TI_FLAGS($8)
+ and $5, _TIF_WORK_MASK, $2
+ bne $5, work_pending
+restore_all:
+ RESTORE_ALL
+ call_pal PAL_rti
+
+ .align 3
+$syscall_error:
+ /*
+ * Some system calls (e.g., ptrace) can return arbitrary
+ * values which might normally be mistaken as error numbers.
+ * Those functions must zero $0 (v0) directly in the stack
+ * frame to indicate that a negative return value wasn't an
+ * error number..
+ */
+ ldq $19, 0($sp) /* old syscall nr (zero if success) */
+ beq $19, $ret_success
+
+ ldq $20, 72($sp) /* .. and this a3 */
+ subq $31, $0, $0 /* with error in v0 */
+ addq $31, 1, $1 /* set a3 for errno return */
+ stq $0, 0($sp)
+ mov $31, $26 /* tell "ret_from_sys_call" we can restart */
+ stq $1, 72($sp) /* a3 for return */
+ br ret_from_sys_call
+
+$ret_success:
+ stq $0, 0($sp)
+ stq $31, 72($sp) /* a3=0 => no error */
+ br ret_from_sys_call
+.end entSys
+
+/*
+ * Do all cleanup when returning from all interrupts and system calls.
+ *
+ * Arguments:
+ * $5: TI_FLAGS.
+ * $8: current.
+ * $19: The old syscall number, or zero if this is not a return
+ * from a syscall that errored and is possibly restartable.
+ * $20: Error indication.
+ */
+
+ .align 4
+ .ent work_pending
+work_pending:
+ and $5, _TIF_NEED_RESCHED, $2
+ beq $2, $work_notifysig
+
+$work_resched:
+ subq $sp, 16, $sp
+ stq $19, 0($sp) /* save syscall nr */
+ stq $20, 8($sp) /* and error indication (a3) */
+ jsr $26, schedule
+ ldq $19, 0($sp)
+ ldq $20, 8($sp)
+ addq $sp, 16, $sp
+ /* Make sure need_resched and sigpending don't change between
+ sampling and the rti. */
+ lda $16, 7
+ call_pal PAL_swpipl
+ ldl $5, TI_FLAGS($8)
+ and $5, _TIF_WORK_MASK, $2
+ beq $2, restore_all
+ and $5, _TIF_NEED_RESCHED, $2
+ bne $2, $work_resched
+
+$work_notifysig:
+ mov $sp, $17
+ br $1, do_switch_stack
+ mov $5, $21
+ mov $sp, $18
+ mov $31, $16
+ jsr $26, do_notify_resume
+ bsr $1, undo_switch_stack
+ br restore_all
+.end work_pending
+
+/*
+ * PTRACE syscall handler
+ */
+
+ .align 4
+ .ent strace
+strace:
+ /* set up signal stack, call syscall_trace */
+ bsr $1, do_switch_stack
+ jsr $26, syscall_trace
+ bsr $1, undo_switch_stack
+
+ /* get the system call number and the arguments back.. */
+ ldq $0, 0($sp)
+ ldq $16, SP_OFF+24($sp)
+ ldq $17, SP_OFF+32($sp)
+ ldq $18, SP_OFF+40($sp)
+ ldq $19, 72($sp)
+ ldq $20, 80($sp)
+ ldq $21, 88($sp)
+
+ /* get the system call pointer.. */
+ lda $1, NR_SYSCALLS($31)
+ lda $2, sys_call_table
+ lda $27, alpha_ni_syscall
+ cmpult $0, $1, $1
+ s8addq $0, $2, $2
+ beq $1, 1f
+ ldq $27, 0($2)
+1: jsr $26, ($27), sys_gettimeofday
+ ldgp $gp, 0($26)
+
+ /* check return.. */
+ blt $0, $strace_error /* the call failed */
+ stq $31, 72($sp) /* a3=0 => no error */
+$strace_success:
+ stq $0, 0($sp) /* save return value */
+
+ bsr $1, do_switch_stack
+ jsr $26, syscall_trace
+ bsr $1, undo_switch_stack
+ br $31, ret_from_sys_call
+
+ .align 3
+$strace_error:
+ ldq $19, 0($sp) /* old syscall nr (zero if success) */
+ beq $19, $strace_success
+ ldq $20, 72($sp) /* .. and this a3 */
+
+ subq $31, $0, $0 /* with error in v0 */
+ addq $31, 1, $1 /* set a3 for errno return */
+ stq $0, 0($sp)
+ stq $1, 72($sp) /* a3 for return */
+
+ bsr $1, do_switch_stack
+ mov $19, $9 /* save old syscall number */
+ mov $20, $10 /* save old a3 */
+ jsr $26, syscall_trace
+ mov $9, $19
+ mov $10, $20
+ bsr $1, undo_switch_stack
+
+ mov $31, $26 /* tell "ret_from_sys_call" we can restart */
+ br ret_from_sys_call
+.end strace
+
+/*
+ * Save and restore the switch stack -- aka the balance of the user context.
+ */
+
+ .align 4
+ .ent do_switch_stack
+do_switch_stack:
+ lda $sp, -SWITCH_STACK_SIZE($sp)
+ stq $9, 0($sp)
+ stq $10, 8($sp)
+ stq $11, 16($sp)
+ stq $12, 24($sp)
+ stq $13, 32($sp)
+ stq $14, 40($sp)
+ stq $15, 48($sp)
+ stq $26, 56($sp)
+ stt $f0, 64($sp)
+ stt $f1, 72($sp)
+ stt $f2, 80($sp)
+ stt $f3, 88($sp)
+ stt $f4, 96($sp)
+ stt $f5, 104($sp)
+ stt $f6, 112($sp)
+ stt $f7, 120($sp)
+ stt $f8, 128($sp)
+ stt $f9, 136($sp)
+ stt $f10, 144($sp)
+ stt $f11, 152($sp)
+ stt $f12, 160($sp)
+ stt $f13, 168($sp)
+ stt $f14, 176($sp)
+ stt $f15, 184($sp)
+ stt $f16, 192($sp)
+ stt $f17, 200($sp)
+ stt $f18, 208($sp)
+ stt $f19, 216($sp)
+ stt $f20, 224($sp)
+ stt $f21, 232($sp)
+ stt $f22, 240($sp)
+ stt $f23, 248($sp)
+ stt $f24, 256($sp)
+ stt $f25, 264($sp)
+ stt $f26, 272($sp)
+ stt $f27, 280($sp)
+ mf_fpcr $f0 # get fpcr
+ stt $f28, 288($sp)
+ stt $f29, 296($sp)
+ stt $f30, 304($sp)
+ stt $f0, 312($sp) # save fpcr in slot of $f31
+ ldt $f0, 64($sp) # dont let "do_switch_stack" change fp state.
+ ret $31, ($1), 1
+.end do_switch_stack
+
+ .align 4
+ .ent undo_switch_stack
+undo_switch_stack:
+ ldq $9, 0($sp)
+ ldq $10, 8($sp)
+ ldq $11, 16($sp)
+ ldq $12, 24($sp)
+ ldq $13, 32($sp)
+ ldq $14, 40($sp)
+ ldq $15, 48($sp)
+ ldq $26, 56($sp)
+ ldt $f30, 312($sp) # get saved fpcr
+ ldt $f0, 64($sp)
+ ldt $f1, 72($sp)
+ ldt $f2, 80($sp)
+ ldt $f3, 88($sp)
+ mt_fpcr $f30 # install saved fpcr
+ ldt $f4, 96($sp)
+ ldt $f5, 104($sp)
+ ldt $f6, 112($sp)
+ ldt $f7, 120($sp)
+ ldt $f8, 128($sp)
+ ldt $f9, 136($sp)
+ ldt $f10, 144($sp)
+ ldt $f11, 152($sp)
+ ldt $f12, 160($sp)
+ ldt $f13, 168($sp)
+ ldt $f14, 176($sp)
+ ldt $f15, 184($sp)
+ ldt $f16, 192($sp)
+ ldt $f17, 200($sp)
+ ldt $f18, 208($sp)
+ ldt $f19, 216($sp)
+ ldt $f20, 224($sp)
+ ldt $f21, 232($sp)
+ ldt $f22, 240($sp)
+ ldt $f23, 248($sp)
+ ldt $f24, 256($sp)
+ ldt $f25, 264($sp)
+ ldt $f26, 272($sp)
+ ldt $f27, 280($sp)
+ ldt $f28, 288($sp)
+ ldt $f29, 296($sp)
+ ldt $f30, 304($sp)
+ lda $sp, SWITCH_STACK_SIZE($sp)
+ ret $31, ($1), 1
+.end undo_switch_stack
+
+/*
+ * The meat of the context switch code.
+ */
+
+ .align 4
+ .globl alpha_switch_to
+ .ent alpha_switch_to
+alpha_switch_to:
+ .prologue 0
+ bsr $1, do_switch_stack
+ call_pal PAL_swpctx
+ lda $8, 0x3fff
+ bsr $1, undo_switch_stack
+ bic $sp, $8, $8
+ mov $17, $0
+ ret
+.end alpha_switch_to
+
+/*
+ * New processes begin life here.
+ */
+
+ .globl ret_from_fork
+ .align 4
+ .ent ret_from_fork
+ret_from_fork:
+ lda $26, ret_from_sys_call
+ mov $17, $16
+ jmp $31, schedule_tail
+.end ret_from_fork
+
+/*
+ * kernel_thread(fn, arg, clone_flags)
+ */
+ .align 4
+ .globl kernel_thread
+ .ent kernel_thread
+kernel_thread:
+ /* We can be called from a module. */
+ ldgp $gp, 0($27)
+ .prologue 1
+ subq $sp, SP_OFF+6*8, $sp
+ br $1, 2f /* load start address */
+
+ /* We've now "returned" from a fake system call. */
+ unop
+ blt $0, 1f /* error? */
+ ldi $1, 0x3fff
+ beq $20, 1f /* parent or child? */
+
+ bic $sp, $1, $8 /* in child. */
+ jsr $26, ($27)
+ ldgp $gp, 0($26)
+ mov $0, $16
+ mov $31, $26
+ jmp $31, sys_exit
+
+1: ret /* in parent. */
+
+ .align 4
+2: /* Fake a system call stack frame, as we can't do system calls
+ from kernel space. Note that we store FN and ARG as they
+ need to be set up in the child for the call. Also store $8
+ and $26 for use in the parent. */
+ stq $31, SP_OFF($sp) /* ps */
+ stq $1, SP_OFF+8($sp) /* pc */
+ stq $gp, SP_OFF+16($sp) /* gp */
+ stq $16, 136($sp) /* $27; FN for child */
+ stq $17, SP_OFF+24($sp) /* $16; ARG for child */
+ stq $8, 64($sp) /* $8 */
+ stq $26, 128($sp) /* $26 */
+ /* Avoid the HAE being gratuitously wrong, to avoid restoring it. */
+ ldq $2, alpha_mv+HAE_CACHE
+ stq $2, 152($sp) /* HAE */
+
+ /* Shuffle FLAGS to the front; add CLONE_VM. */
+ ldi $1, CLONE_VM|CLONE_UNTRACED
+ or $18, $1, $16
+ bsr $26, sys_clone
+
+ /* We don't actually care for a3 success widgetry in the kernel.
+ Not for positive errno values. */
+ stq $0, 0($sp) /* $0 */
+ br restore_all
+.end kernel_thread
+
+/*
+ * execve(path, argv, envp)
+ */
+ .align 4
+ .globl execve
+ .ent execve
+execve:
+ /* We can be called from a module. */
+ ldgp $gp, 0($27)
+ lda $sp, -(32+SIZEOF_PT_REGS+8)($sp)
+ .frame $sp, 32+SIZEOF_PT_REGS+8, $26, 0
+ stq $26, 0($sp)
+ stq $16, 8($sp)
+ stq $17, 16($sp)
+ stq $18, 24($sp)
+ .prologue 1
+
+ lda $16, 32($sp)
+ lda $17, 0
+ lda $18, SIZEOF_PT_REGS
+ bsr $26, memset !samegp
+
+ /* Avoid the HAE being gratuitously wrong, which would cause us
+ to do the whole turn off interrupts thing and restore it. */
+ ldq $2, alpha_mv+HAE_CACHE
+ stq $2, 152+32($sp)
+
+ ldq $16, 8($sp)
+ ldq $17, 16($sp)
+ ldq $18, 24($sp)
+ lda $19, 32($sp)
+ bsr $26, do_execve !samegp
+
+ ldq $26, 0($sp)
+ bne $0, 1f /* error! */
+
+ /* Move the temporary pt_regs struct from its current location
+ to the top of the kernel stack frame. See copy_thread for
+ details for a normal process. */
+ lda $16, 0x4000 - SIZEOF_PT_REGS($8)
+ lda $17, 32($sp)
+ lda $18, SIZEOF_PT_REGS
+ bsr $26, memmove !samegp
+
+ /* Take that over as our new stack frame and visit userland! */
+ lda $sp, 0x4000 - SIZEOF_PT_REGS($8)
+ br $31, ret_from_sys_call
+
+1: lda $sp, 32+SIZEOF_PT_REGS+8($sp)
+ ret
+.end execve
+
+
+/*
+ * Special system calls. Most of these are special in that they either
+ * have to play switch_stack games or in some way use the pt_regs struct.
+ */
+ .align 4
+ .globl sys_fork
+ .ent sys_fork
+sys_fork:
+ .prologue 0
+ mov $sp, $21
+ bsr $1, do_switch_stack
+ bis $31, SIGCHLD, $16
+ mov $31, $17
+ mov $31, $18
+ mov $31, $19
+ mov $31, $20
+ jsr $26, alpha_clone
+ bsr $1, undo_switch_stack
+ ret
+.end sys_fork
+
+ .align 4
+ .globl sys_clone
+ .ent sys_clone
+sys_clone:
+ .prologue 0
+ mov $sp, $21
+ bsr $1, do_switch_stack
+ /* $16, $17, $18, $19, $20 come from the user. */
+ jsr $26, alpha_clone
+ bsr $1, undo_switch_stack
+ ret
+.end sys_clone
+
+ .align 4
+ .globl sys_vfork
+ .ent sys_vfork
+sys_vfork:
+ .prologue 0
+ mov $sp, $16
+ bsr $1, do_switch_stack
+ jsr $26, alpha_vfork
+ bsr $1, undo_switch_stack
+ ret
+.end sys_vfork
+
+ .align 4
+ .globl sys_sigreturn
+ .ent sys_sigreturn
+sys_sigreturn:
+ .prologue 0
+ mov $sp, $17
+ lda $18, -SWITCH_STACK_SIZE($sp)
+ lda $sp, -SWITCH_STACK_SIZE($sp)
+ jsr $26, do_sigreturn
+ br $1, undo_switch_stack
+ br ret_from_sys_call
+.end sys_sigreturn
+
+ .align 4
+ .globl sys_rt_sigreturn
+ .ent sys_rt_sigreturn
+sys_rt_sigreturn:
+ .prologue 0
+ mov $sp, $17
+ lda $18, -SWITCH_STACK_SIZE($sp)
+ lda $sp, -SWITCH_STACK_SIZE($sp)
+ jsr $26, do_rt_sigreturn
+ br $1, undo_switch_stack
+ br ret_from_sys_call
+.end sys_rt_sigreturn
+
+ .align 4
+ .globl sys_sigsuspend
+ .ent sys_sigsuspend
+sys_sigsuspend:
+ .prologue 0
+ mov $sp, $17
+ br $1, do_switch_stack
+ mov $sp, $18
+ subq $sp, 16, $sp
+ stq $26, 0($sp)
+ jsr $26, do_sigsuspend
+ ldq $26, 0($sp)
+ lda $sp, SWITCH_STACK_SIZE+16($sp)
+ ret
+.end sys_sigsuspend
+
+ .align 4
+ .globl sys_rt_sigsuspend
+ .ent sys_rt_sigsuspend
+sys_rt_sigsuspend:
+ .prologue 0
+ mov $sp, $18
+ br $1, do_switch_stack
+ mov $sp, $19
+ subq $sp, 16, $sp
+ stq $26, 0($sp)
+ jsr $26, do_rt_sigsuspend
+ ldq $26, 0($sp)
+ lda $sp, SWITCH_STACK_SIZE+16($sp)
+ ret
+.end sys_rt_sigsuspend
+
+ .align 4
+ .globl sys_sethae
+ .ent sys_sethae
+sys_sethae:
+ .prologue 0
+ stq $16, 152($sp)
+ ret
+.end sys_sethae
+
+ .align 4
+ .globl osf_getpriority
+ .ent osf_getpriority
+osf_getpriority:
+ lda $sp, -16($sp)
+ stq $26, 0($sp)
+ .prologue 0
+
+ jsr $26, sys_getpriority
+
+ ldq $26, 0($sp)
+ blt $0, 1f
+
+ /* Return value is the unbiased priority, i.e. 20 - prio.
+ This does result in negative return values, so signal
+ no error by writing into the R0 slot. */
+ lda $1, 20
+ stq $31, 16($sp)
+ subl $1, $0, $0
+ unop
+
+1: lda $sp, 16($sp)
+ ret
+.end osf_getpriority
+
+ .align 4
+ .globl sys_getxuid
+ .ent sys_getxuid
+sys_getxuid:
+ .prologue 0
+ ldq $2, TI_TASK($8)
+ ldl $0, TASK_UID($2)
+ ldl $1, TASK_EUID($2)
+ stq $1, 80($sp)
+ ret
+.end sys_getxuid
+
+ .align 4
+ .globl sys_getxgid
+ .ent sys_getxgid
+sys_getxgid:
+ .prologue 0
+ ldq $2, TI_TASK($8)
+ ldl $0, TASK_GID($2)
+ ldl $1, TASK_EGID($2)
+ stq $1, 80($sp)
+ ret
+.end sys_getxgid
+
+ .align 4
+ .globl sys_getxpid
+ .ent sys_getxpid
+sys_getxpid:
+ .prologue 0
+ ldq $2, TI_TASK($8)
+
+ /* See linux/kernel/timer.c sys_getppid for discussion
+ about this loop. */
+ ldq $3, TASK_REAL_PARENT($2)
+1: ldl $1, TASK_TGID($3)
+#ifdef CONFIG_SMP
+ mov $3, $4
+ mb
+ ldq $3, TASK_REAL_PARENT($2)
+ cmpeq $3, $4, $4
+ beq $4, 1b
+#endif
+ stq $1, 80($sp)
+ ldl $0, TASK_TGID($2)
+ ret
+.end sys_getxpid
+
+ .align 4
+ .globl sys_pipe
+ .ent sys_pipe
+sys_pipe:
+ lda $sp, -16($sp)
+ stq $26, 0($sp)
+ .prologue 0
+
+ lda $16, 8($sp)
+ jsr $26, do_pipe
+
+ ldq $26, 0($sp)
+ bne $0, 1f
+
+ /* The return values are in $0 and $20. */
+ ldl $1, 12($sp)
+ ldl $0, 8($sp)
+
+ stq $1, 80+16($sp)
+1: lda $sp, 16($sp)
+ ret
+.end sys_pipe
+
+ .align 4
+ .globl sys_ptrace
+ .ent sys_ptrace
+sys_ptrace:
+ .prologue 0
+ mov $sp, $20
+ jmp $31, do_sys_ptrace
+.end sys_ptrace
+
+ .align 4
+ .globl sys_execve
+ .ent sys_execve
+sys_execve:
+ .prologue 0
+ mov $sp, $19
+ jmp $31, do_sys_execve
+.end sys_execve
+
+ .align 4
+ .globl osf_sigprocmask
+ .ent osf_sigprocmask
+osf_sigprocmask:
+ .prologue 0
+ mov $sp, $18
+ jmp $31, do_osf_sigprocmask
+.end osf_sigprocmask
+
+ .align 4
+ .globl alpha_ni_syscall
+ .ent alpha_ni_syscall
+alpha_ni_syscall:
+ .prologue 0
+ /* Special because it also implements overflow handling via
+ syscall number 0. And if you recall, zero is a special
+ trigger for "not an error". Store large non-zero there. */
+ lda $0, -ENOSYS
+ unop
+ stq $0, 0($sp)
+ ret
+.end alpha_ni_syscall