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Ignore whitespace Rev 2781 → Rev 2782

/tags/0.3.0/uspace/lib/libc/arch/ia32/src/fibril.S
0,0 → 1,79
#
# 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.
# - Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
# - The name of the author may not be used to endorse or promote products
# derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
 
#include <kernel/arch/context_offset.h>
 
.text
 
.global context_save
.global context_restore
 
 
## Save current CPU context
#
# Save CPU context to the context_t variable
# pointed by the 1st argument. Returns 1 in EAX.
#
context_save:
movl 0(%esp),%eax # the caller's return %eip
movl 4(%esp),%edx # address of the context variable to save context to
 
# save registers to the context structure
CONTEXT_SAVE_ARCH_CORE %edx %eax
 
# Save TLS
movl %gs:0, %eax
movl %eax, OFFSET_TLS(%edx) # tls -> ctx->tls
xorl %eax,%eax # context_save returns 1
incl %eax
ret
 
 
## Restore saved CPU context
#
# Restore CPU context from context_t variable
# pointed by the 1st argument. Returns 0 in EAX.
#
context_restore:
movl 4(%esp),%eax # address of the context variable to restore context from
 
# restore registers from the context structure
CONTEXT_RESTORE_ARCH_CORE %eax %edx
 
movl %edx,0(%esp) # ctx->pc -> saver's return %eip
 
# Set thread local storage
pushl %edx
movl OFFSET_TLS(%eax), %edx # Set arg1 to TLS addr
movl $1, %eax # Syscall SYS_TLS_SET
int $0x30
popl %edx
xorl %eax,%eax # context_restore returns 0
ret