[PATCH 11/18] pc-bios/s390-ccw: Remove panics from Netboot IPL path

[jrossi@linux.ibm.com]

From: Jared Rossi <jrossi@linux.ibm.com>

Remove panic-on-error from Netboot specific functions so that error recovery
may be possible in the future.

Functions that would previously panic now provide a return code.

Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>

---
 pc-bios/s390-ccw/s390-ccw.h   |  2 +-
 pc-bios/s390-ccw/bootmap.c    |  1 +
 pc-bios/s390-ccw/netmain.c    | 22 +++++++++++++++-------
 pc-bios/s390-ccw/virtio-net.c |  7 +++++--
 4 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/pc-bios/s390-ccw/s390-ccw.h b/pc-bios/s390-ccw/s390-ccw.h
index cbd92f3671..8dac070257 100644
--- a/pc-bios/s390-ccw/s390-ccw.h
+++ b/pc-bios/s390-ccw/s390-ccw.h
@@ -57,7 +57,7 @@ unsigned int get_loadparm_index(void);
 void main(void);
 
 /* netmain.c */
-void netmain(void);
+int netmain(void);
 
 /* sclp.c */
 void sclp_print(const char *string);
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index dc7200c264..9459e19ffb 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -1059,6 +1059,7 @@ void zipl_load(void)
 
     if (virtio_get_device_type() == VIRTIO_ID_NET) {
         netmain();
+        panic("\n! Cannot IPL from this network !\n");
     }
 
     if (ipl_scsi()) {
diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
index bc6ad8695f..013f94d932 100644
--- a/pc-bios/s390-ccw/netmain.c
+++ b/pc-bios/s390-ccw/netmain.c
@@ -464,7 +464,7 @@ static bool find_net_dev(Schib *schib, int dev_no)
     return false;
 }
 
-static void virtio_setup(void)
+static int virtio_setup(void)
 {
     Schib schib;
     int ssid;
@@ -479,7 +479,10 @@ static void virtio_setup(void)
     enable_mss_facility();
 
     if (store_iplb(&iplb)) {
-        IPL_assert(iplb.pbt == S390_IPL_TYPE_CCW, "IPL_TYPE_CCW expected");
+        if (iplb.pbt != S390_IPL_TYPE_CCW) {
+            puts("IPL_TYPE_CCW expected");
+        }
+
         dev_no = iplb.ccw.devno;
         debug_print_int("device no. ", dev_no);
         net_schid.ssid = iplb.ccw.ssid & 0x3;
@@ -495,10 +498,10 @@ static void virtio_setup(void)
         }
     }
 
-    IPL_assert(found, "No virtio net device found");
+    return found;
 }
 
-void netmain(void)
+int netmain(void)
 {
     filename_ip_t fn_ip;
     int rc, fnlen;
@@ -506,11 +509,15 @@ void netmain(void)
     sclp_setup();
     puts("Network boot starting...");
 
-    virtio_setup();
+    if (!virtio_setup()) {
+        puts("No virtio net device found.");
+        return 1;
+    }
 
     rc = net_init(&fn_ip);
     if (rc) {
-        panic("Network initialization failed. Halting.");
+        puts("Network initialization failed.");
+        return 1;
     }
 
     fnlen = strlen(fn_ip.filename);
@@ -528,5 +535,6 @@ void netmain(void)
         jump_to_low_kernel();
     }
 
-    panic("Failed to load OS from network.");
+    puts("Failed to load OS from network.");
+    return 1;
 }
diff --git a/pc-bios/s390-ccw/virtio-net.c b/pc-bios/s390-ccw/virtio-net.c
index 2fcb0a58c5..f9854a22c3 100644
--- a/pc-bios/s390-ccw/virtio-net.c
+++ b/pc-bios/s390-ccw/virtio-net.c
@@ -54,8 +54,11 @@ int virtio_net_init(void *mac_addr)
     vdev->guest_features[0] = VIRTIO_NET_F_MAC_BIT;
     virtio_setup_ccw(vdev);
 
-    IPL_assert(vdev->guest_features[0] & VIRTIO_NET_F_MAC_BIT,
-               "virtio-net device does not support the MAC address feature");
+    if (!(vdev->guest_features[0] & VIRTIO_NET_F_MAC_BIT)) {
+        puts("virtio-net device does not support the MAC address feature");
+        return -1;
+    }
+
     memcpy(mac_addr, vdev->config.net.mac, ETH_ALEN);
 
     for (i = 0; i < 64; i++) {
-- 
2.45.1