Loading...
/* * __get_user functions. * * (C) Copyright 1998 Linus Torvalds * * These functions have a non-standard call interface * to make them more efficient, especially as they * return an error value in addition to the "real" * return value. */ #include <linux/linkage.h> #include <asm/dwarf2.h> #include <asm/thread_info.h> /* * __get_user_X * * Inputs: %eax contains the address * * Outputs: %eax is error code (0 or -EFAULT) * %edx contains zero-extended value * * These functions should not modify any other registers, * as they get called from within inline assembly. */ .text ENTRY(__get_user_1) CFI_STARTPROC GET_THREAD_INFO(%edx) cmpl TI_addr_limit(%edx),%eax jae bad_get_user 1: movzbl (%eax),%edx xorl %eax,%eax ret CFI_ENDPROC ENDPROC(__get_user_1) ENTRY(__get_user_2) CFI_STARTPROC addl $1,%eax jc bad_get_user GET_THREAD_INFO(%edx) cmpl TI_addr_limit(%edx),%eax jae bad_get_user 2: movzwl -1(%eax),%edx xorl %eax,%eax ret CFI_ENDPROC ENDPROC(__get_user_2) ENTRY(__get_user_4) CFI_STARTPROC addl $3,%eax jc bad_get_user GET_THREAD_INFO(%edx) cmpl TI_addr_limit(%edx),%eax jae bad_get_user 3: movl -3(%eax),%edx xorl %eax,%eax ret CFI_ENDPROC ENDPROC(__get_user_4) bad_get_user: CFI_STARTPROC xorl %edx,%edx movl $-14,%eax ret CFI_ENDPROC END(bad_get_user) .section __ex_table,"a" .long 1b,bad_get_user .long 2b,bad_get_user .long 3b,bad_get_user .previous |