#
# Copyright (c) 2001-2004 Jakub Jermar
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
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# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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.text

.global context_save
.global context_restore

#include <kernel/arch/context_offset.h>

## Save current CPU context
#
# Save CPU context to context_t variable
# pointed by the 1st argument. Returns 1 in EAX.
#
context_save:
	movq (%rsp), %rdx     # the caller's return %eip
	
	# In %edi is passed 1st argument
	CONTEXT_SAVE_ARCH_CORE %rdi %rdx 
	
	# Save TLS
	movq %fs:0, %rax
	movq %rax, OFFSET_TLS(%rdi)
		
	xorq %rax,%rax		# context_save returns 1
	incq %rax
	ret


## Restore current CPU context
#
# Restore CPU context from context_t variable
# pointed by the 1st argument. Returns 0 in EAX.
#
context_restore:
	
	CONTEXT_RESTORE_ARCH_CORE %rdi %rdx
	
	movq %rdx,(%rsp)

	# Set thread local storage
	movq OFFSET_TLS(%rdi), %rdi   # Set arg1 to TLS addr
	movq $1, %rax		# SYS_TLS_SET
	syscall

	xorq %rax,%rax		# context_restore returns 0
	ret