pc-bios/s390-ccw Really big EAV ECKD DASD handling

For EAV ECKD DASD, the cylinder count will have the magic value
0xfffeU. Therefore, use the block number to test for valid eckd
addresses instead.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 15 insertions, 16 deletions

diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index e4352b16cd..d4c579c245 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -93,11 +93,23 @@ static inline void verify_boot_info(BootInfo *bip)
                "Bad block size in zIPL section of the 1st record.");
 }
 
-static bool eckd_valid_address(BootMapPointer *p)
+static block_number_t eckd_block_num(BootMapPointer *p)
 {
+    const uint64_t sectors = virtio_get_sectors();
+    const uint64_t heads = virtio_get_heads();
     const uint64_t cylinder = p->eckd.cylinder
                             + ((p->eckd.head & 0xfff0) << 12);
     const uint64_t head = p->eckd.head & 0x000f;
+    const block_number_t block = sectors * heads * cylinder
+                               + sectors * head
+                               + p->eckd.sector
+                               - 1; /* block nr starts with zero */
+    return block;
+}
+
+static bool eckd_valid_address(BootMapPointer *p)
+{
+    const uint64_t head = p->eckd.head & 0x000f;
 
     if (head >= virtio_get_heads()
         ||  p->eckd.sector > virtio_get_sectors()
@@ -105,27 +117,14 @@ static bool eckd_valid_address(BootMapPointer *p)
         return false;
     }
 
-    if (!virtio_guessed_disk_nature() && cylinder >= virtio_get_cylinders()) {
+    if (!virtio_guessed_disk_nature() &&
+        eckd_block_num(p) >= virtio_get_blocks()) {
         return false;
     }
 
     return true;
 }
 
-static block_number_t eckd_block_num(BootMapPointer *p)
-{
-    const uint64_t sectors = virtio_get_sectors();
-    const uint64_t heads = virtio_get_heads();
-    const uint64_t cylinder = p->eckd.cylinder
-                            + ((p->eckd.head & 0xfff0) << 12);
-    const uint64_t head = p->eckd.head & 0x000f;
-    const block_number_t block = sectors * heads * cylinder
-                               + sectors * head
-                               + p->eckd.sector
-                               - 1; /* block nr starts with zero */
-    return block;
-}
-
 static block_number_t load_eckd_segments(block_number_t blk, uint64_t *address)
 {
     block_number_t block_nr;