[S390] dasd: add large volume support

The dasd device driver will now support ECKD devices with more then
65520 cylinders.
In the traditional ECKD adressing scheme each track is addressed
by a 16-bit cylinder and 16-bit head number. The new addressing
scheme makes use of the fact that the actual number of heads is
never larger then 15, so 12 bits of the head number can be redefined
to be part of the cylinder address.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 14 insertions, 2 deletions

diff --git a/arch/s390/include/asm/vtoc.h b/arch/s390/include/asm/vtoc.h
index 3a5267d90d29..8406a2b3157a 100644
--- a/arch/s390/include/asm/vtoc.h
+++ b/arch/s390/include/asm/vtoc.h
@@ -39,7 +39,7 @@ struct vtoc_labeldate
         __u16 day;
 } __attribute__ ((packed));
 
-struct vtoc_volume_label
+struct vtoc_volume_label_cdl
 {
         char volkey[4];         /* volume key = volume label */
         char vollbl[4];         /* volume label */
@@ -56,6 +56,14 @@ struct vtoc_volume_label
         char res3[29];          /* reserved */
 } __attribute__ ((packed));
 
+struct vtoc_volume_label_ldl {
+        char vollbl[4];         /* volume label */
+        char volid[6];          /* volume identifier */
+        char res3[69];          /* reserved */
+        char ldl_version;       /* version number, valid for ldl format */
+        __u64 formatted_blocks; /* valid when ldl_version >= f2  */
+} __attribute__ ((packed));
+
 struct vtoc_extent
 {
         __u8 typeind;                   /* extent type indicator */
@@ -140,7 +148,11 @@ struct vtoc_format4_label
         char res2[10];          /* reserved */
         __u8 DS4EFLVL;          /* extended free-space management level */
         struct vtoc_cchhb DS4EFPTR; /* pointer to extended free-space info */
-        char res3[9];           /* reserved */
+        char res3;              /* reserved */
+        __u32 DS4DCYL;          /* number of logical cyls */
+        char res4[2];           /* reserved */
+        __u8 DS4DEVF2;          /* device flags */
+        char res5;              /* reserved */
 } __attribute__ ((packed));
 
 struct vtoc_ds5ext