arch/s390/kvm/sie64a.S

   1 /*
   2  * sie64a.S - low level sie call
   3  *
   4  * Copyright IBM Corp. 2008,2010
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License (version 2 only)
   8  * as published by the Free Software Foundation.
   9  *
  10  *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
  11  *               Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
  12  */
  13
  14 #include <linux/errno.h>
  15 #include <asm/asm-offsets.h>
  16 #include <asm/setup.h>
  17 #include <asm/asm-offsets.h>
  18 #include <asm/ptrace.h>
  19 #include <asm/thread_info.h>
  20
  21 _TIF_EXIT_SIE = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING)
  22
  23 /*
  24  * offsets into stackframe
  25  * SP_  = offsets into stack sie64 is called with
  26  * SPI_ = offsets into irq stack
  27  */
  28 SP_GREGS = __SF_EMPTY
  29 SP_HOOK  = __SF_EMPTY+8
  30 SP_GPP   = __SF_EMPTY+16
  31 SPI_PSW  = STACK_FRAME_OVERHEAD + __PT_PSW
  32
  33
  34         .macro SPP newpp
  35         tm      __LC_MACHINE_FLAGS+6,0x20       # MACHINE_FLAG_SPP
  36         jz      0f
  37         .insn   s,0xb2800000,\newpp
  38 0:
  39         .endm
  40
  41 sie_irq_handler:
  42         SPP     __LC_CMF_HPP                    # set host id
  43         larl    %r2,sie_inst
  44         clg     %r2,SPI_PSW+8(0,%r15)           # intercepted sie
  45         jne     1f
  46         xc      __LC_SIE_HOOK(8),__LC_SIE_HOOK
  47         lg      %r2,__LC_THREAD_INFO            # pointer thread_info struct
  48         tm      __TI_flags+7(%r2),_TIF_EXIT_SIE
  49         jz      0f
  50         larl    %r2,sie_exit                    # work pending, leave sie
  51         stg     %r2,__LC_RETURN_PSW+8
  52         br      %r14
  53 0:      larl    %r2,sie_reenter                 # re-enter with guest id
  54         stg     %r2,__LC_RETURN_PSW+8
  55 1:      br      %r14
  56
  57 /*
  58  * sie64a calling convention:
  59  * %r2 pointer to sie control block
  60  * %r3 guest register save area
  61  */
  62         .globl  sie64a
  63 sie64a:
  64         stg     %r3,SP_GREGS(%r15)              # save guest register save area
  65         stmg    %r6,%r14,__SF_GPRS(%r15)        # save registers on entry
  66         lgr     %r14,%r2                        # pointer to sie control block
  67         larl    %r5,sie_irq_handler
  68         stg     %r2,SP_GPP(%r15)
  69         stg     %r5,SP_HOOK(%r15)               # save hook target
  70         lmg     %r0,%r13,0(%r3)                 # load guest gprs 0-13
  71 sie_reenter:
  72         mvc     __LC_SIE_HOOK(8),SP_HOOK(%r15)
  73         SPP     SP_GPP(%r15)                    # set guest id
  74 sie_inst:
  75         sie     0(%r14)
  76         xc      __LC_SIE_HOOK(8),__LC_SIE_HOOK
  77         SPP     __LC_CMF_HPP                    # set host id
  78 sie_exit:
  79         lg      %r14,SP_GREGS(%r15)
  80         stmg    %r0,%r13,0(%r14)                # save guest gprs 0-13
  81         lghi    %r2,0
  82         lmg     %r6,%r14,__SF_GPRS(%r15)
  83         br      %r14
  84
  85 sie_err:
  86         xc      __LC_SIE_HOOK(8),__LC_SIE_HOOK
  87         SPP     __LC_CMF_HPP                    # set host id
  88         lg      %r14,SP_GREGS(%r15)
  89         stmg    %r0,%r13,0(%r14)                # save guest gprs 0-13
  90         lghi    %r2,-EFAULT
  91         lmg     %r6,%r14,__SF_GPRS(%r15)
  92         br      %r14
  93
  94         .section __ex_table,"a"
  95         .quad   sie_inst,sie_err
  96         .previous