From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH] zcrypt: handle AP Info notification from CHSC SEI command References: <1548870526-30595-1-git-send-email-akrowiak@linux.ibm.com> <95a29dd5-11d5-0984-ffbd-73ef92ed1aba@linux.ibm.com> From: Tony Krowiak Date: Thu, 31 Jan 2019 18:32:30 -0500 MIME-Version: 1.0 In-Reply-To: <95a29dd5-11d5-0984-ffbd-73ef92ed1aba@linux.ibm.com> Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Language: en-US Content-Transfer-Encoding: 8bit Message-Id: Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: pmorel@linux.ibm.com, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org Cc: schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, sebott@linux.ibm.com, oberpar@linux.ibm.com, freude@linux.ibm.com, pasic@linux.ibm.com, cohuck@redhat.com List-ID: On 1/31/19 4:09 AM, Pierre Morel wrote: > On 30/01/2019 18:48, Tony Krowiak wrote: >> The current AP bus implementation periodically polls the AP configuration >> to detect changes. When the AP configuration is dynamically changed >> via the >> SE or an SCLP instruction, the changes will not be reflected to sysfs >> until >> the next time the AP configuration is polled. The CHSC architecture >> provides a Store Event Information (SEI)command to make notification >> of an >> AP configuration change. This patch introduces a handler to process >> notification from the CHSC SEI command BY immediately kickING off an >> AP bus >> scan. >> >> Signed-off-by: Tony Krowiak >> Reviewed-by: Halil Pasic >> --- >>   arch/s390/include/asm/ap.h   | 12 ++++++++++++ >>   drivers/s390/cio/chsc.c      | 12 ++++++++++++ >>   drivers/s390/cio/chsc.h      |  1 + >>   drivers/s390/crypto/ap_bus.c | 12 ++++++++++++ >>   4 files changed, 37 insertions(+) >> >> diff --git a/arch/s390/include/asm/ap.h b/arch/s390/include/asm/ap.h >> index 1a6a7092d942..c778593d509f 100644 >> --- a/arch/s390/include/asm/ap.h >> +++ b/arch/s390/include/asm/ap.h >> @@ -360,4 +360,16 @@ static inline struct ap_queue_status >> ap_dqap(ap_qid_t qid, >>       return reg1; >>   } >> +/* >> + * Interface to tell the AP bus code that a configuration >> + * change has happened. The bus code should at least do >> + * an ap bus resource rescan. >> + */ >> +#if IS_ENABLED(CONFIG_ZCRYPT) >> +void ap_bus_cfg_chg(void); >> +#else >> +#error "no CONFIG_ZCRYPT" >> +static void ap_bus_cfg_chg(void){}; >> +#endif >> + >>   #endif /* _ASM_S390_AP_H_ */ >> diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c >> index a0baee25134c..dccccc337078 100644 >> --- a/drivers/s390/cio/chsc.c >> +++ b/drivers/s390/cio/chsc.c >> @@ -586,6 +586,15 @@ static void chsc_process_sei_scm_avail(struct >> chsc_sei_nt0_area *sei_area) >>                     " failed (rc=%d).\n", ret); >>   } >> +static void chsc_process_sei_ap_cfg_chg(struct chsc_sei_nt0_area >> *sei_area) >> +{ >> +    CIO_CRW_EVENT(3, "chsc: ap config changed\n"); >> +    if (sei_area->rs != 5) > > Why just return if the rs code is 5? > > The event content code concerns the AP configuration change. > > Should the source of the reporting of this change hold us from > rescanning the available AP? Why rescan if the RS code does not indicate the AP configuration changed? > > > Regards, > Pierre > > >> +        return; >> + >> +    ap_bus_cfg_chg(); >> +} >> + >>   static void chsc_process_sei_nt2(struct chsc_sei_nt2_area *sei_area) >>   { >>       switch (sei_area->cc) { >> @@ -612,6 +621,9 @@ static void chsc_process_sei_nt0(struct >> chsc_sei_nt0_area *sei_area) >>       case 2: /* i/o resource accessibility */ >>           chsc_process_sei_res_acc(sei_area); >>           break; >> +    case 3: /* ap config changed */ >> +        chsc_process_sei_ap_cfg_chg(sei_area); >> +        break; >>       case 7: /* channel-path-availability information */ >>           chsc_process_sei_chp_avail(sei_area); >>           break; >> diff --git a/drivers/s390/cio/chsc.h b/drivers/s390/cio/chsc.h >> index 78aba8d94eec..5651066c46e3 100644 >> --- a/drivers/s390/cio/chsc.h >> +++ b/drivers/s390/cio/chsc.h >> @@ -9,6 +9,7 @@ >>   #include >>   #include >>   #include >> +#include >>   #define CHSC_SDA_OC_MSS   0x2 >> diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c >> index 48ea0004a56d..94f621783d6b 100644 >> --- a/drivers/s390/crypto/ap_bus.c >> +++ b/drivers/s390/crypto/ap_bus.c >> @@ -35,6 +35,7 @@ >>   #include >>   #include >>   #include >> +#include >>   #include "ap_bus.h" >>   #include "ap_debug.h" >> @@ -860,6 +861,17 @@ void ap_bus_force_rescan(void) >>   EXPORT_SYMBOL(ap_bus_force_rescan); >>   /* >> +* A config change has happened, Force an ap bus rescan. >> +*/ >> +void ap_bus_cfg_chg(void) >> +{ >> +    AP_DBF(DBF_INFO, "%s config change, forcing bus rescan\n", >> __func__); >> + >> +    ap_bus_force_rescan(); >> +} >> +EXPORT_SYMBOL(ap_bus_cfg_chg); >> + >> +/* >>    * hex2bitmap() - parse hex mask string and set bitmap. >>    * Valid strings are "0x012345678" with at least one valid hex number. >>    * Rest of the bitmap to the right is padded with 0. No spaces allowed >> > >