[S390] Cleanup of CHSC event handling.

Change CHSC event handling to be more easily extensible.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 112 insertions, 120 deletions

diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index 0260f12231e0..c6db7f44689a 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -461,144 +461,136 @@ __get_chpid_from_lir(void *data)
         return (u16) (lir->indesc[0]&0x000000ff);
 }
 
-int
-chsc_process_crw(void)
+struct chsc_sei_area {
+        struct chsc_header request;
+        u32 reserved1;
+        u32 reserved2;
+        u32 reserved3;
+        struct chsc_header response;
+        u32 reserved4;
+        u8  flags;
+        u8  vf;         /* validity flags */
+        u8  rs;         /* reporting source */
+        u8  cc;         /* content code */
+        u16 fla;        /* full link address */
+        u16 rsid;       /* reporting source id */
+        u32 reserved5;
+        u32 reserved6;
+        u8 ccdf[4096 - 16 - 24];        /* content-code dependent field */
+        /* ccdf has to be big enough for a link-incident record */
+} __attribute__ ((packed));
+
+static int chsc_process_sei_link_incident(struct chsc_sei_area *sei_area)
+{
+        int chpid;
+
+        CIO_CRW_EVENT(4, "chsc: link incident (rs=%02x, rs_id=%04x)\n",
+                      sei_area->rs, sei_area->rsid);
+        if (sei_area->rs != 4)
+                return 0;
+        chpid = __get_chpid_from_lir(sei_area->ccdf);
+        if (chpid < 0)
+                CIO_CRW_EVENT(4, "chsc: link incident - invalid LIR\n");
+        else
+                s390_set_chpid_offline(chpid);
+
+        return 0;
+}
+
+static int chsc_process_sei_res_acc(struct chsc_sei_area *sei_area)
 {
-        int chpid, ret;
         struct res_acc_data res_data;
-        struct {
-                struct chsc_header request;
-                u32 reserved1;
-                u32 reserved2;
-                u32 reserved3;
-                struct chsc_header response;
-                u32 reserved4;
-                u8  flags;
-                u8  vf;         /* validity flags */
-                u8  rs;         /* reporting source */
-                u8  cc;         /* content code */
-                u16 fla;        /* full link address */
-                u16 rsid;       /* reporting source id */
-                u32 reserved5;
-                u32 reserved6;
-                u32 ccdf[96];   /* content-code dependent field */
-                /* ccdf has to be big enough for a link-incident record */
-        } __attribute__ ((packed)) *sei_area;
+        struct device *dev;
+        int status;
+        int rc;
+
+        CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
+                      "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
+        if (sei_area->rs != 4)
+                return 0;
+        /* allocate a new channel path structure, if needed */
+        status = get_chp_status(sei_area->rsid);
+        if (status < 0)
+                new_channel_path(sei_area->rsid);
+        else if (!status)
+                return 0;
+        dev = get_device(&css[0]->chps[sei_area->rsid]->dev);
+        memset(&res_data, 0, sizeof(struct res_acc_data));
+        res_data.chp = to_channelpath(dev);
+        if ((sei_area->vf & 0xc0) != 0) {
+                res_data.fla = sei_area->fla;
+                if ((sei_area->vf & 0xc0) == 0xc0)
+                        /* full link address */
+                        res_data.fla_mask = 0xffff;
+                else
+                        /* link address */
+                        res_data.fla_mask = 0xff00;
+        }
+        rc = s390_process_res_acc(&res_data);
+        put_device(dev);
+
+        return rc;
+}
+
+static int chsc_process_sei(struct chsc_sei_area *sei_area)
+{
+        int rc;
+
+        /* Check if we might have lost some information. */
+        if (sei_area->flags & 0x40)
+                CIO_CRW_EVENT(2, "chsc: event overflow\n");
+        /* which kind of information was stored? */
+        rc = 0;
+        switch (sei_area->cc) {
+        case 1: /* link incident*/
+                rc = chsc_process_sei_link_incident(sei_area);
+                break;
+        case 2: /* i/o resource accessibiliy */
+                rc = chsc_process_sei_res_acc(sei_area);
+                break;
+        default: /* other stuff */
+                CIO_CRW_EVENT(4, "chsc: unhandled sei content code %d\n",
+                              sei_area->cc);
+                break;
+        }
+
+        return rc;
+}
+
+int chsc_process_crw(void)
+{
+        struct chsc_sei_area *sei_area;
+        int ret;
+        int rc;
 
         if (!sei_page)
                 return 0;
-        /*
-         * build the chsc request block for store event information
-         * and do the call
-         * This function is only called by the machine check handler thread,
-         * so we don't need locking for the sei_page.
-         */
+        /* Access to sei_page is serialized through machine check handler
+         * thread, so no need for locking. */
         sei_area = sei_page;
 
         CIO_TRACE_EVENT( 2, "prcss");
         ret = 0;
         do {
-                int ccode, status;
-                struct device *dev;
                 memset(sei_area, 0, sizeof(*sei_area));
-                memset(&res_data, 0, sizeof(struct res_acc_data));
                 sei_area->request.length = 0x0010;
                 sei_area->request.code = 0x000e;
+                if (chsc(sei_area))
+                        break;
 
-                ccode = chsc(sei_area);
-                if (ccode > 0)
-                        return 0;
-
-                switch (sei_area->response.code) {
-                        /* for debug purposes, check for problems */
-                case 0x0001:
-                        CIO_CRW_EVENT(4, "chsc_process_crw: event information "
-                                        "successfully stored\n");
-                        break; /* everything ok */
-                case 0x0002:
-                        CIO_CRW_EVENT(2,
-                                      "chsc_process_crw: invalid command!\n");
-                        return 0;
-                case 0x0003:
-                        CIO_CRW_EVENT(2, "chsc_process_crw: error in chsc "
-                                      "request block!\n");
-                        return 0;
-                case 0x0005:
-                        CIO_CRW_EVENT(2, "chsc_process_crw: no event "
-                                      "information stored\n");
-                        return 0;
-                default:
-                        CIO_CRW_EVENT(2, "chsc_process_crw: chsc response %d\n",
+                if (sei_area->response.code == 0x0001) {
+                        CIO_CRW_EVENT(4, "chsc: sei successful\n");
+                        rc = chsc_process_sei(sei_area);
+                        if (rc)
+                                ret = rc;
+                } else {
+                        CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x)\n",
                                       sei_area->response.code);
-                        return 0;
-                }
-
-                /* Check if we might have lost some information. */
-                if (sei_area->flags & 0x40)
-                        CIO_CRW_EVENT(2, "chsc_process_crw: Event information "
-                                       "has been lost due to overflow!\n");
-
-                if (sei_area->rs != 4) {
-                        CIO_CRW_EVENT(2, "chsc_process_crw: reporting source "
-                                      "(%04X) isn't a chpid!\n",
-                                      sei_area->rsid);
-                        continue;
-                }
-
-                /* which kind of information was stored? */
-                switch (sei_area->cc) {
-                case 1: /* link incident*/
-                        CIO_CRW_EVENT(4, "chsc_process_crw: "
-                                      "channel subsystem reports link incident,"
-                                      " reporting source is chpid %x\n",
-                                      sei_area->rsid);
-                        chpid = __get_chpid_from_lir(sei_area->ccdf);
-                        if (chpid < 0)
-                                CIO_CRW_EVENT(4, "%s: Invalid LIR, skipping\n",
-                                              __FUNCTION__);
-                        else
-                                s390_set_chpid_offline(chpid);
-                        break;
-                        
-                case 2: /* i/o resource accessibiliy */
-                        CIO_CRW_EVENT(4, "chsc_process_crw: "
-                                      "channel subsystem reports some I/O "
-                                      "devices may have become accessible\n");
-                        pr_debug("Data received after sei: \n");
-                        pr_debug("Validity flags: %x\n", sei_area->vf);
-                        
-                        /* allocate a new channel path structure, if needed */
-                        status = get_chp_status(sei_area->rsid);
-                        if (status < 0)
-                                new_channel_path(sei_area->rsid);
-                        else if (!status)
-                                break;
-                        dev = get_device(&css[0]->chps[sei_area->rsid]->dev);
-                        res_data.chp = to_channelpath(dev);
-                        pr_debug("chpid: %x", sei_area->rsid);
-                        if ((sei_area->vf & 0xc0) != 0) {
-                                res_data.fla = sei_area->fla;
-                                if ((sei_area->vf & 0xc0) == 0xc0) {
-                                        pr_debug(" full link addr: %x",
-                                                 sei_area->fla);
-                                        res_data.fla_mask = 0xffff;
-                                } else {
-                                        pr_debug(" link addr: %x",
-                                                 sei_area->fla);
-                                        res_data.fla_mask = 0xff00;
-                                }
-                        }
-                        ret = s390_process_res_acc(&res_data);
-                        pr_debug("\n\n");
-                        put_device(dev);
-                        break;
-                        
-                default: /* other stuff */
-                        CIO_CRW_EVENT(4, "chsc_process_crw: event %d\n",
-                                      sei_area->cc);
+                        ret = 0;
                         break;
                 }
         } while (sei_area->flags & 0x80);
+
         return ret;
 }