[Qemu-devel] [PATCH v1 1/4] s390-ccw: ipl structs for eckd cdl/ldl

["Collin L. Walling" <walling@linux.vnet.ibm.com>]

ECKD DASDs have different IPL structures for CDL and LDL
formats. The current Ipl1 and Ipl2 structs follow the CDL
format, so we prepend "EckdCdl" to them. A new struct,
EckdLdlIpl1 is introduced and contains boot info for LDL.

Also introduce structs for IPL stages 1 and 1b and for
disk geometry.

Signed-off-by: Collin L. Walling <walling@linux.vnet.ibm.com>
Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com>
---
 pc-bios/s390-ccw/bootmap.c | 24 ++++++++++----------
 pc-bios/s390-ccw/bootmap.h | 55 +++++++++++++++++++++++++++++++++-------------
 2 files changed, 53 insertions(+), 26 deletions(-)

diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index 6f8e30f..5546b79 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -221,9 +221,9 @@ static void run_eckd_boot_script(block_number_t mbr_block_nr)
 static void ipl_eckd_cdl(void)
 {
     XEckdMbr *mbr;
-    Ipl2 *ipl2 = (void *)sec;
+    EckdCdlIpl2 *ipl2 = (void *)sec;
     IplVolumeLabel *vlbl = (void *)sec;
-    block_number_t block_nr;
+    block_number_t mbr_block_nr;
 
     /* we have just read the block #0 and recognized it as "IPL1" */
     sclp_print("CDL\n");
@@ -231,7 +231,7 @@ static void ipl_eckd_cdl(void)
     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
     read_block(1, ipl2, "Cannot read IPL2 record at block 1");
 
-    mbr = &ipl2->u.x.mbr;
+    mbr = &ipl2->mbr;
     IPL_assert(magic_match(mbr, ZIPL_MAGIC), "No zIPL section in IPL2 record.");
     IPL_assert(block_size_ok(mbr->blockptr.xeckd.bptr.size),
                "Bad block size in zIPL section of IPL2 record.");
@@ -239,7 +239,7 @@ static void ipl_eckd_cdl(void)
                "Non-ECKD device type in zIPL section of IPL2 record.");
 
     /* save pointer to Boot Script */
-    block_nr = eckd_block_num((void *)&(mbr->blockptr));
+    mbr_block_nr = eckd_block_num((void *)&(mbr->blockptr));
 
     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
     read_block(2, vlbl, "Cannot read Volume Label at block 2");
@@ -249,7 +249,7 @@ static void ipl_eckd_cdl(void)
                "Invalid magic of volser block");
     print_volser(vlbl->f.volser);
 
-    run_eckd_boot_script(block_nr);
+    run_eckd_boot_script(mbr_block_nr);
     /* no return */
 }
 
@@ -280,8 +280,8 @@ static void print_eckd_ldl_msg(ECKD_IPL_mode_t mode)
 
 static void ipl_eckd_ldl(ECKD_IPL_mode_t mode)
 {
-    block_number_t block_nr;
-    BootInfo *bip = (void *)(sec + 0x70); /* BootInfo is MBR for LDL */
+    block_number_t mbr_block_nr;
+    EckdLdlIpl1 *ipl1 = (void *)sec;
 
     if (mode != ECKD_LDL_UNLABELED) {
         print_eckd_ldl_msg(mode);
@@ -292,15 +292,17 @@ static void ipl_eckd_ldl(ECKD_IPL_mode_t mode)
     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
     read_block(0, sec, "Cannot read block 0 to grab boot info.");
     if (mode == ECKD_LDL_UNLABELED) {
-        if (!magic_match(bip->magic, ZIPL_MAGIC)) {
+        if (!magic_match(ipl1->boot_info.magic, ZIPL_MAGIC)) {
             return; /* not applicable layout */
         }
         sclp_print("unlabeled LDL.\n");
     }
-    verify_boot_info(bip);
+    verify_boot_info(&ipl1->boot_info);
+
+    mbr_block_nr =
+        eckd_block_num((void *)&(ipl1->boot_info.bp.ipl.bm_ptr.eckd.bptr));
 
-    block_nr = eckd_block_num((void *)&(bip->bp.ipl.bm_ptr.eckd.bptr));
-    run_eckd_boot_script(block_nr);
+    run_eckd_boot_script(mbr_block_nr);
     /* no return */
 }
 
diff --git a/pc-bios/s390-ccw/bootmap.h b/pc-bios/s390-ccw/bootmap.h
index 4980838..a2b4695 100644
--- a/pc-bios/s390-ccw/bootmap.h
+++ b/pc-bios/s390-ccw/bootmap.h
@@ -226,22 +226,47 @@ typedef struct BootInfo {          /* @ 0x70, record #0    */
     } bp;
 } __attribute__ ((packed)) BootInfo; /* see also XEckdMbr   */
 
-typedef struct Ipl1 {
-    unsigned char key[4]; /* == "IPL1" */
-    unsigned char data[24];
-} __attribute__((packed)) Ipl1;
+/*
+ * Structs for IPL
+ */
+#define STAGE2_BLK_CNT_MAX  24 /* Stage 1b can load up to 24 blocks */
 
-typedef struct Ipl2 {
-    unsigned char key[4]; /* == "IPL2" */
-    union {
-        unsigned char data[144];
-        struct {
-            unsigned char reserved1[92-4];
-            XEckdMbr mbr;
-            unsigned char reserved2[144-(92-4)-sizeof(XEckdMbr)];
-        } x;
-    } u;
-} __attribute__((packed)) Ipl2;
+typedef struct EckdCdlIpl1 {
+    uint8_t key[4]; /* == "IPL1" */
+    uint8_t data[24];
+} __attribute__((packed)) EckdCdlIpl1;
+
+typedef struct BootEckdSeekarg {
+    uint16_t pad;
+    uint16_t cyl;
+    uint16_t head;
+    uint8_t sec;
+    uint8_t pad2;
+} __attribute__ ((packed)) BootEckdSeekarg;
+
+typedef struct BootEckdStage1b {
+    uint8_t reserved[32 * STAGE2_BLK_CNT_MAX];
+    struct BootEckdSeekarg seek[STAGE2_BLK_CNT_MAX];
+    uint8_t unused[64];
+} __attribute__ ((packed)) BootEckdStage1b;
+
+typedef struct BootEckdStage1 {
+    uint8_t reserved[72];
+    struct BootEckdSeekarg seek[2];
+} __attribute__ ((packed)) BootEckdStage1;
+
+typedef struct EckdCdlIpl2 {
+    uint8_t key[4]; /* == "IPL2" */
+    struct BootEckdStage1 stage1;
+    XEckdMbr mbr;
+    uint8_t reserved2[24];
+} __attribute__((packed)) EckdCdlIpl2;
+
+typedef struct EckdLdlIpl1 {
+    uint8_t reserved[24];
+    struct BootEckdStage1 stage1;
+    BootInfo boot_info; /* BootInfo is MBR for LDL */
+} __attribute__((packed)) EckdLdlIpl1;
 
 typedef struct IplVolumeLabel {
     unsigned char key[4]; /* == "VOL1" */
-- 
2.7.4