On 10/11/2017 05:47 AM, Dong Jia Shi wrote: > * Halil Pasic <pa...@linux.vnet.ibm.com> [2017-10-04 17:41:39 +0200]: > >> Simplify the error handling of the SSCH and RSCH handler avoiding >> arbitrary and cryptic error codes being used to tell how the instruction >> is supposed to end. Let the code detecting the condition tell how it's >> to be handled in a less ambiguous way. It's best to handle SSCH and RSCH >> in one go as the emulation of the two shares a lot of code. >> >> For passthrough this change isn't pure refactoring, but changes the >> way kernel reported EFAULT is handled. After clarifying the kernel >> interface we decided that EFAULT shall be mapped to unit exception. >> Same goes for unexpected error codes. >> >> Signed-off-by: Halil Pasic <pa...@linux.vnet.ibm.com> >> --- >> >> AFAIR we decided in the previous round to rather do transformation >> and fixing in one patch than touch stuff twice. Hence this patch >> ain't pure transformation any more. >> --- >> hw/s390x/css.c | 83 >> +++++++++++++-------------------------------- >> hw/s390x/s390-ccw.c | 11 +++--- >> hw/vfio/ccw.c | 30 ++++++++++++---- >> include/hw/s390x/css.h | 24 +++++++++---- >> include/hw/s390x/s390-ccw.h | 2 +- >> target/s390x/ioinst.c | 53 ++++------------------------- >> 6 files changed, 77 insertions(+), 126 deletions(-) >> >> diff --git a/hw/s390x/css.c b/hw/s390x/css.c >> index 4f47dbc8b0..b2978c3bae 100644 >> --- a/hw/s390x/css.c >> +++ b/hw/s390x/css.c >> @@ -1003,12 +1003,11 @@ static void sch_handle_start_func_virtual(SubchDev >> *sch) >> >> } >> >> -static int sch_handle_start_func_passthrough(SubchDev *sch) >> +static IOInstEnding sch_handle_start_func_passthrough(SubchDev *sch) >> { >> >> PMCW *p = &sch->curr_status.pmcw; >> SCSW *s = &sch->curr_status.scsw; >> - int ret; >> >> ORB *orb = &sch->orb; >> if (!(s->ctrl & SCSW_ACTL_SUSP)) { >> @@ -1022,31 +1021,11 @@ static int >> sch_handle_start_func_passthrough(SubchDev *sch) >> */ >> if (!(orb->ctrl0 & ORB_CTRL0_MASK_PFCH) || >> !(orb->ctrl0 & ORB_CTRL0_MASK_C64)) { >> - return -EINVAL; >> + sch_gen_unit_exception(sch); >> + css_inject_io_interrupt(sch); >> + return (IOInstEnding){.cc = 0}; > This behavior change is not mentioned in the commit message. Right? > No this particular change is not. Should I mention it explicitly? Maybe "Same goes for unexpected error codes and absence of required ORB flags."
> [...] > >> diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c >> index a8baadf57a..dbb5b201de 100644 >> --- a/hw/vfio/ccw.c >> +++ b/hw/vfio/ccw.c >> @@ -23,6 +23,7 @@ >> #include "hw/s390x/s390-ccw.h" >> #include "hw/s390x/ccw-device.h" >> #include "qemu/error-report.h" >> +#include "cpu.h" > We need this because? > No idea -- was not intentional. Probably slipped in when rebasing, or I don't know. >> >> #define TYPE_VFIO_CCW "vfio-ccw" >> typedef struct VFIOCCWDevice { >> @@ -47,9 +48,9 @@ struct VFIODeviceOps vfio_ccw_ops = { >> .vfio_compute_needs_reset = vfio_ccw_compute_needs_reset, >> }; >> >> -static int vfio_ccw_handle_request(ORB *orb, SCSW *scsw, void *data) >> +static IOInstEnding vfio_ccw_handle_request(SubchDev *sch) >> { >> - S390CCWDevice *cdev = data; >> + S390CCWDevice *cdev = sch->driver_data; >> VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev); >> struct ccw_io_region *region = vcdev->io_region; >> int ret; >> @@ -60,8 +61,8 @@ static int vfio_ccw_handle_request(ORB *orb, SCSW *scsw, >> void *data) >> >> memset(region, 0, sizeof(*region)); >> >> - memcpy(region->orb_area, orb, sizeof(ORB)); >> - memcpy(region->scsw_area, scsw, sizeof(SCSW)); >> + memcpy(region->orb_area, &sch->orb, sizeof(ORB)); >> + memcpy(region->scsw_area, &sch->curr_status.scsw, sizeof(SCSW)); >> >> again: >> ret = pwrite(vcdev->vdev.fd, region, >> @@ -71,10 +72,25 @@ again: >> goto again; >> } >> error_report("vfio-ccw: wirte I/O region failed with errno=%d", >> errno); >> - return -errno; >> + ret = -errno; >> + } else { >> + ret = region->ret_code; >> + } >> + switch (-ret) { >> + /* Currently we don't update control block and just return the cc code. >> */ > This is not true anymore? At least for the EFAULT case. > Right I shall remove this. >> + case 0: >> + return (IOInstEnding){.cc = 0}; >> + case EBUSY: >> + return (IOInstEnding){.cc = 2}; >> + case ENODEV: >> + case EACCES: >> + return (IOInstEnding){.cc = 3}; >> + case EFAULT: >> + default: >> + sch_gen_unit_exception(sch); >> + css_inject_io_interrupt(sch); >> + return (IOInstEnding){.cc = 0}; >> } >> - >> - return region->ret_code; >> } >> >> static void vfio_ccw_reset(DeviceState *dev) >> diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h >> index 66916b6546..2116c6b3c7 100644 >> --- a/include/hw/s390x/css.h >> +++ b/include/hw/s390x/css.h > [...] > >> @@ -197,13 +208,14 @@ SubchDev *css_find_subch(uint8_t m, uint8_t cssid, >> uint8_t ssid, >> uint16_t schid); >> bool css_subch_visible(SubchDev *sch); >> void css_conditional_io_interrupt(SubchDev *sch); >> + > Extra change. > Should be removed. >> int css_do_stsch(SubchDev *sch, SCHIB *schib); >> bool css_schid_final(int m, uint8_t cssid, uint8_t ssid, uint16_t schid); >> int css_do_msch(SubchDev *sch, const SCHIB *schib); > [...] >