Some ECKD bootmap code was using structs designed for SCSI.
Even though this works, it confuses readability. Add a new
BootMapTable struct to assist with readability in bootmap
entry code. Also:
- replace ScsiMbr in ECKD code with appropriate structs
- fix read_block messages to reflect BootMapTable
- fixup ipl_scsi to use BootMapTable (referred to as Program Table)
- defined value for maximum table entries
Signed-off-by: Collin L. Walling <walling@linux.vnet.ibm.com>
---
pc-bios/s390-ccw/bootmap.c | 60 +++++++++++++++++++++-------------------------
pc-bios/s390-ccw/bootmap.h | 14 +++++++++--
2 files changed, 39 insertions(+), 35 deletions(-)
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index 67a6123..286de40 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -182,24 +182,24 @@ static block_number_t load_eckd_segments(block_number_t blk, uint64_t *address)
return block_nr;
}
-static void run_eckd_boot_script(block_number_t mbr_block_nr)
+static void run_eckd_boot_script(block_number_t bmt_block_nr)
{
int i;
unsigned int loadparm = get_loadparm_index();
block_number_t block_nr;
uint64_t address;
- ScsiMbr *bte = (void *)sec; /* Eckd bootmap table entry */
+ BootMapTable *bmt = (void *)sec;
BootMapScript *bms = (void *)sec;
debug_print_int("loadparm", loadparm);
- IPL_assert(loadparm < 31, "loadparm value greater than"
+ IPL_assert(loadparm <= MAX_TABLE_ENTRIES, "loadparm value greater than"
" maximum number of boot entries allowed");
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
- read_block(mbr_block_nr, sec, "Cannot read MBR");
+ read_block(bmt_block_nr, sec, "Cannot read Boot Map Table");
- block_nr = eckd_block_num((void *)&(bte->blockptr[loadparm]));
- IPL_assert(block_nr != -1, "No Boot Map");
+ block_nr = eckd_block_num((void *)&bmt->entry[loadparm]);
+ IPL_assert(block_nr != -1, "Cannot find Boot Map Table Entry");
memset(sec, FREE_SPACE_FILLER, sizeof(sec));
read_block(block_nr, sec, "Cannot read Boot Map Script");
@@ -223,7 +223,7 @@ static void ipl_eckd_cdl(void)
XEckdMbr *mbr;
Ipl2 *ipl2 = (void *)sec;
IplVolumeLabel *vlbl = (void *)sec;
- block_number_t block_nr;
+ block_number_t bmt_block_nr;
/* we have just read the block #0 and recognized it as "IPL1" */
sclp_print("CDL\n");
@@ -238,8 +238,8 @@ static void ipl_eckd_cdl(void)
IPL_assert(mbr->dev_type == DEV_TYPE_ECKD,
"Non-ECKD device type in zIPL section of IPL2 record.");
- /* save pointer to Boot Script */
- block_nr = eckd_block_num((void *)&(mbr->blockptr));
+ /* save pointer to Boot Map Table */
+ bmt_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(bmt_block_nr);
/* no return */
}
@@ -280,7 +280,7 @@ 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;
+ block_number_t bmt_block_nr;
BootInfo *bip = (void *)(sec + 0x70); /* BootInfo is MBR for LDL */
if (mode != ECKD_LDL_UNLABELED) {
@@ -299,8 +299,10 @@ static void ipl_eckd_ldl(ECKD_IPL_mode_t mode)
}
verify_boot_info(bip);
- block_nr = eckd_block_num((void *)&(bip->bp.ipl.bm_ptr.eckd.bptr));
- run_eckd_boot_script(block_nr);
+ /* save pointer to Boot Map Table */
+ bmt_block_nr = eckd_block_num((void *)&bip->bp.ipl.bm_ptr.eckd.bptr);
+
+ run_eckd_boot_script(bmt_block_nr);
/* no return */
}
@@ -325,7 +327,7 @@ static void print_eckd_msg(void)
static void ipl_eckd(void)
{
- ScsiMbr *mbr = (void *)sec;
+ XEckdMbr *mbr = (void *)sec;
LDL_VTOC *vlbl = (void *)sec;
print_eckd_msg();
@@ -449,10 +451,8 @@ static void zipl_run(ScsiBlockPtr *pte)
static void ipl_scsi(void)
{
ScsiMbr *mbr = (void *)sec;
- uint8_t *ns, *ns_end;
int program_table_entries = 0;
- const int pte_len = sizeof(ScsiBlockPtr);
- ScsiBlockPtr *prog_table_entry = NULL;
+ BootMapTable *prog_table = (void *)sec;
unsigned int loadparm = get_loadparm_index();
/* Grab the MBR */
@@ -467,34 +467,28 @@ static void ipl_scsi(void)
debug_print_int("MBR Version", mbr->version_id);
IPL_check(mbr->version_id == 1,
"Unknown MBR layout version, assuming version 1");
- debug_print_int("program table", mbr->blockptr[0].blockno);
- IPL_assert(mbr->blockptr[0].blockno, "No Program Table");
+ debug_print_int("program table", mbr->pt.blockno);
+ IPL_assert(mbr->pt.blockno, "No Program Table");
/* Parse the program table */
- read_block(mbr->blockptr[0].blockno, sec,
- "Error reading Program Table");
-
+ read_block(mbr->pt.blockno, sec, "Error reading Program Table");
IPL_assert(magic_match(sec, ZIPL_MAGIC), "No zIPL magic in PT");
- debug_print_int("loadparm index", loadparm);
- ns_end = sec + virtio_get_block_size();
- for (ns = (sec + pte_len); (ns + pte_len) < ns_end; ns += pte_len) {
- prog_table_entry = (ScsiBlockPtr *)ns;
- if (!prog_table_entry->blockno) {
+ while (program_table_entries <= MAX_TABLE_ENTRIES) {
+ if (!prog_table->entry[program_table_entries].scsi.blockno) {
break;
}
-
program_table_entries++;
- if (program_table_entries == loadparm + 1) {
- break; /* selected entry found */
- }
}
debug_print_int("program table entries", program_table_entries);
-
IPL_assert(program_table_entries != 0, "Empty Program Table");
- zipl_run(prog_table_entry); /* no return */
+ debug_print_int("loadparm", loadparm);
+ IPL_assert(loadparm <= MAX_TABLE_ENTRIES, "loadparm value greater than"
+ " maximum number of boot entries allowed");
+
+ zipl_run(&prog_table->entry[loadparm].scsi); /* no return */
}
/***********************************************************************
diff --git a/pc-bios/s390-ccw/bootmap.h b/pc-bios/s390-ccw/bootmap.h
index cf99a4c..850b655 100644
--- a/pc-bios/s390-ccw/bootmap.h
+++ b/pc-bios/s390-ccw/bootmap.h
@@ -53,6 +53,15 @@ typedef union BootMapPointer {
ExtEckdBlockPtr xeckd;
} __attribute__ ((packed)) BootMapPointer;
+#define MAX_TABLE_ENTRIES 30
+
+/* aka Program Table */
+typedef struct BootMapTable {
+ uint8_t magic[4];
+ uint8_t reserved[12];
+ BootMapPointer entry[];
+} __attribute__ ((packed)) BootMapTable;
+
typedef struct ComponentEntry {
ScsiBlockPtr data;
uint8_t pad[7];
@@ -69,8 +78,9 @@ typedef struct ComponentHeader {
typedef struct ScsiMbr {
uint8_t magic[4];
uint32_t version_id;
- uint8_t reserved[8];
- ScsiBlockPtr blockptr[];
+ uint8_t reserved1[8];
+ ScsiBlockPtr pt; /* block pointer to program table */
+ uint8_t reserved2[120];
} __attribute__ ((packed)) ScsiMbr;
#define ZIPL_MAGIC "zIPL"
--
2.7.4
On 15.02.2018 23:54, Collin L. Walling wrote:
> Some ECKD bootmap code was using structs designed for SCSI.
> Even though this works, it confuses readability. Add a new
> BootMapTable struct to assist with readability in bootmap
> entry code. Also:
>
> - replace ScsiMbr in ECKD code with appropriate structs
> - fix read_block messages to reflect BootMapTable
> - fixup ipl_scsi to use BootMapTable (referred to as Program Table)
> - defined value for maximum table entries
>
> Signed-off-by: Collin L. Walling <walling@linux.vnet.ibm.com>
> ---
> pc-bios/s390-ccw/bootmap.c | 60 +++++++++++++++++++++-------------------------
> pc-bios/s390-ccw/bootmap.h | 14 +++++++++--
> 2 files changed, 39 insertions(+), 35 deletions(-)
[...]
> diff --git a/pc-bios/s390-ccw/bootmap.h b/pc-bios/s390-ccw/bootmap.h
> index cf99a4c..850b655 100644
> --- a/pc-bios/s390-ccw/bootmap.h
> +++ b/pc-bios/s390-ccw/bootmap.h
> @@ -53,6 +53,15 @@ typedef union BootMapPointer {
> ExtEckdBlockPtr xeckd;
> } __attribute__ ((packed)) BootMapPointer;
>
> +#define MAX_TABLE_ENTRIES 30
> +
> +/* aka Program Table */
> +typedef struct BootMapTable {
> + uint8_t magic[4];
> + uint8_t reserved[12];
> + BootMapPointer entry[];
> +} __attribute__ ((packed)) BootMapTable;
> +
> typedef struct ComponentEntry {
> ScsiBlockPtr data;
> uint8_t pad[7];
> @@ -69,8 +78,9 @@ typedef struct ComponentHeader {
> typedef struct ScsiMbr {
> uint8_t magic[4];
> uint32_t version_id;
> - uint8_t reserved[8];
> - ScsiBlockPtr blockptr[];
> + uint8_t reserved1[8];
> + ScsiBlockPtr pt; /* block pointer to program table */
> + uint8_t reserved2[120];
Did you want to pad the struct to 512 bytes here? If so, I think that
should have been "uint32_t" instead of "uint8_t" or "480" instead of "120" ?
> } __attribute__ ((packed)) ScsiMbr;
>
> #define ZIPL_MAGIC "zIPL"
>
Thomas
On 16.02.2018 11:42, Thomas Huth wrote:
> On 15.02.2018 23:54, Collin L. Walling wrote:
>> Some ECKD bootmap code was using structs designed for SCSI.
>> Even though this works, it confuses readability. Add a new
>> BootMapTable struct to assist with readability in bootmap
>> entry code. Also:
>>
>> - replace ScsiMbr in ECKD code with appropriate structs
>> - fix read_block messages to reflect BootMapTable
>> - fixup ipl_scsi to use BootMapTable (referred to as Program Table)
>> - defined value for maximum table entries
>>
>> Signed-off-by: Collin L. Walling <walling@linux.vnet.ibm.com>
>> ---
>> pc-bios/s390-ccw/bootmap.c | 60 +++++++++++++++++++++-------------------------
>> pc-bios/s390-ccw/bootmap.h | 14 +++++++++--
>> 2 files changed, 39 insertions(+), 35 deletions(-)
> [...]
>> diff --git a/pc-bios/s390-ccw/bootmap.h b/pc-bios/s390-ccw/bootmap.h
>> index cf99a4c..850b655 100644
>> --- a/pc-bios/s390-ccw/bootmap.h
>> +++ b/pc-bios/s390-ccw/bootmap.h
>> @@ -53,6 +53,15 @@ typedef union BootMapPointer {
>> ExtEckdBlockPtr xeckd;
>> } __attribute__ ((packed)) BootMapPointer;
>>
>> +#define MAX_TABLE_ENTRIES 30
>> +
>> +/* aka Program Table */
>> +typedef struct BootMapTable {
>> + uint8_t magic[4];
>> + uint8_t reserved[12];
>> + BootMapPointer entry[];
>> +} __attribute__ ((packed)) BootMapTable;
>> +
>> typedef struct ComponentEntry {
>> ScsiBlockPtr data;
>> uint8_t pad[7];
>> @@ -69,8 +78,9 @@ typedef struct ComponentHeader {
>> typedef struct ScsiMbr {
>> uint8_t magic[4];
>> uint32_t version_id;
>> - uint8_t reserved[8];
>> - ScsiBlockPtr blockptr[];
>> + uint8_t reserved1[8];
>> + ScsiBlockPtr pt; /* block pointer to program table */
>> + uint8_t reserved2[120];
>
> Did you want to pad the struct to 512 bytes here? If so, I think that
> should have been "uint32_t" instead of "uint8_t" or "480" instead of "120" ?
>
Should probably be uint8_t[480] then to stay in style with other
reserved field definitions.
>> } __attribute__ ((packed)) ScsiMbr;
>>
>> #define ZIPL_MAGIC "zIPL"
>>
>
> Thomas
>
--
Regards,
Viktor Mihajlovski
On 02/16/2018 07:19 AM, Viktor Mihajlovski wrote:
> On 16.02.2018 11:42, Thomas Huth wrote:
>> On 15.02.2018 23:54, Collin L. Walling wrote:
>>> Some ECKD bootmap code was using structs designed for SCSI.
>>> Even though this works, it confuses readability. Add a new
>>> BootMapTable struct to assist with readability in bootmap
>>> entry code. Also:
>>>
>>> - replace ScsiMbr in ECKD code with appropriate structs
>>> - fix read_block messages to reflect BootMapTable
>>> - fixup ipl_scsi to use BootMapTable (referred to as Program Table)
>>> - defined value for maximum table entries
>>>
>>> Signed-off-by: Collin L. Walling <walling@linux.vnet.ibm.com>
>>> ---
>>> pc-bios/s390-ccw/bootmap.c | 60 +++++++++++++++++++++-------------------------
>>> pc-bios/s390-ccw/bootmap.h | 14 +++++++++--
>>> 2 files changed, 39 insertions(+), 35 deletions(-)
>> [...]
>>> diff --git a/pc-bios/s390-ccw/bootmap.h b/pc-bios/s390-ccw/bootmap.h
>>> index cf99a4c..850b655 100644
>>> --- a/pc-bios/s390-ccw/bootmap.h
>>> +++ b/pc-bios/s390-ccw/bootmap.h
>>> @@ -53,6 +53,15 @@ typedef union BootMapPointer {
>>> ExtEckdBlockPtr xeckd;
>>> } __attribute__ ((packed)) BootMapPointer;
>>>
>>> +#define MAX_TABLE_ENTRIES 30
>>> +
>>> +/* aka Program Table */
>>> +typedef struct BootMapTable {
>>> + uint8_t magic[4];
>>> + uint8_t reserved[12];
>>> + BootMapPointer entry[];
>>> +} __attribute__ ((packed)) BootMapTable;
>>> +
>>> typedef struct ComponentEntry {
>>> ScsiBlockPtr data;
>>> uint8_t pad[7];
>>> @@ -69,8 +78,9 @@ typedef struct ComponentHeader {
>>> typedef struct ScsiMbr {
>>> uint8_t magic[4];
>>> uint32_t version_id;
>>> - uint8_t reserved[8];
>>> - ScsiBlockPtr blockptr[];
>>> + uint8_t reserved1[8];
>>> + ScsiBlockPtr pt; /* block pointer to program table */
>>> + uint8_t reserved2[120];
>> Did you want to pad the struct to 512 bytes here? If so, I think that
>> should have been "uint32_t" instead of "uint8_t" or "480" instead of "120" ?
>>
> Should probably be uint8_t[480] then to stay in style with other
> reserved field definitions.
The idea was to mimic the Scsi MBR struct defined in zipl. It has
reserved space for what would appear to be for 5 more ScsiBlockPtrs
(which are not used in zipl) and a boot_info struct (which we don't need
in QEMU).
Alternatively, I can just omit the reserved2 field. I placed it there
for "completeness" but it is not at all necessary.
>>> } __attribute__ ((packed)) ScsiMbr;
>>>
>>> #define ZIPL_MAGIC "zIPL"
>>>
>> Thomas
>>
>
--
- Collin L Walling
On 16.02.2018 15:57, Collin L. Walling wrote:
> On 02/16/2018 07:19 AM, Viktor Mihajlovski wrote:
>> On 16.02.2018 11:42, Thomas Huth wrote:
>>> On 15.02.2018 23:54, Collin L. Walling wrote:
>>>> Some ECKD bootmap code was using structs designed for SCSI.
>>>> Even though this works, it confuses readability. Add a new
>>>> BootMapTable struct to assist with readability in bootmap
>>>> entry code. Also:
>>>>
>>>> - replace ScsiMbr in ECKD code with appropriate structs
>>>> - fix read_block messages to reflect BootMapTable
>>>> - fixup ipl_scsi to use BootMapTable (referred to as Program Table)
>>>> - defined value for maximum table entries
>>>>
>>>> Signed-off-by: Collin L. Walling <walling@linux.vnet.ibm.com>
>>>> ---
>>>> pc-bios/s390-ccw/bootmap.c | 60
>>>> +++++++++++++++++++++-------------------------
>>>> pc-bios/s390-ccw/bootmap.h | 14 +++++++++--
>>>> 2 files changed, 39 insertions(+), 35 deletions(-)
>>> [...]
>>>> diff --git a/pc-bios/s390-ccw/bootmap.h b/pc-bios/s390-ccw/bootmap.h
>>>> index cf99a4c..850b655 100644
>>>> --- a/pc-bios/s390-ccw/bootmap.h
>>>> +++ b/pc-bios/s390-ccw/bootmap.h
>>>> @@ -53,6 +53,15 @@ typedef union BootMapPointer {
>>>> ExtEckdBlockPtr xeckd;
>>>> } __attribute__ ((packed)) BootMapPointer;
>>>> +#define MAX_TABLE_ENTRIES 30
>>>> +
>>>> +/* aka Program Table */
>>>> +typedef struct BootMapTable {
>>>> + uint8_t magic[4];
>>>> + uint8_t reserved[12];
>>>> + BootMapPointer entry[];
>>>> +} __attribute__ ((packed)) BootMapTable;
>>>> +
>>>> typedef struct ComponentEntry {
>>>> ScsiBlockPtr data;
>>>> uint8_t pad[7];
>>>> @@ -69,8 +78,9 @@ typedef struct ComponentHeader {
>>>> typedef struct ScsiMbr {
>>>> uint8_t magic[4];
>>>> uint32_t version_id;
>>>> - uint8_t reserved[8];
>>>> - ScsiBlockPtr blockptr[];
>>>> + uint8_t reserved1[8];
>>>> + ScsiBlockPtr pt; /* block pointer to program table */
>>>> + uint8_t reserved2[120];
>>> Did you want to pad the struct to 512 bytes here? If so, I think that
>>> should have been "uint32_t" instead of "uint8_t" or "480" instead of
>>> "120" ?
>>>
>> Should probably be uint8_t[480] then to stay in style with other
>> reserved field definitions.
>
> The idea was to mimic the Scsi MBR struct defined in zipl. It has
> reserved space for what would appear to be for 5 more ScsiBlockPtrs
> (which are not used in zipl) and a boot_info struct (which we don't need
> in QEMU).
>
> Alternatively, I can just omit the reserved2 field. I placed it there
> for "completeness" but it is not at all necessary.
I'd say just drop it. It looks rather confusing than helpful to me.
Thomas
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