* [Qemu-devel] [PATCH] scsi disk block descriptor
@ 2009-10-13 20:20 Artyom Tarasenko
2009-10-13 20:34 ` Krumme, Chris
0 siblings, 1 reply; 3+ messages in thread
From: Artyom Tarasenko @ 2009-10-13 20:20 UTC (permalink / raw)
To: qemu-devel, Blue Swirl
[-- Attachment #1: Type: text/plain, Size: 1944 bytes --]
The SCSI-2 documentation suggests, that although the block
descriptor is optional for an arbitrary SCSI-2 device (chapter 8.2.10,
http://ldkelley.com/SCSI2/SCSI2/SCSI2/SCSI2/SCSI2-08.html )
it is mandatory for a disk: chapters 9.1.2, 9.3.3
( http://ldkelley.com/SCSI2/SCSI2/SCSI2/SCSI2-09.html ) don't say
"optional" any more, just "The block descriptor in the MODE SENSE
data describes the block lengths that are used on the medium."
Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com>
---
diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
index 3940726..b703379 100644
--- a/hw/scsi-disk.c
+++ b/hw/scsi-disk.c
@@ -624,7 +624,9 @@ static int32_t scsi_send_command(SCSIDevice *d,
uint32_t tag,
{
uint8_t *p;
int page;
-
+ int dbd;
+
+ dbd = buf[1] & 0x8;
page = buf[2] & 0x3f;
DPRINTF("Mode Sense (page %d, len %d)\n", page, len);
p = outbuf;
@@ -635,6 +637,24 @@ static int32_t scsi_send_command(SCSIDevice *d,
uint32_t tag,
outbuf[2] = 0x80; /* Readonly. */
}
p += 4;
+ bdrv_get_geometry(s->dinfo->bdrv, &nb_sectors);
+ if ((~dbd) & nb_sectors) {
+ nb_sectors /= s->cluster_size;
+ if (nb_sectors > UINT32_MAX)
+ nb_sectors = UINT32_MAX;
+ nb_sectors--;
+ outbuf[3] = 8; /* Block descriptor length */
+ p[0] = 0; /* media density code */
+ p[1] = (nb_sectors >> 16) & 0xff;
+ p[2] = (nb_sectors >> 8) & 0xff;
+ p[3] = nb_sectors & 0xff;
+ p[4] = 0; /* reserved */
+ p[5] = 0; /* bytes 5-7 are the sector size in bytes */
+ p[6] = s->cluster_size * 2;
+ p[7] = 0;
+ p += 8;
+ }
+
if (page == 4) {
int cylinders, heads, secs;
[-- Attachment #2: 0001-scsi-disk-block-descriptor.patch --]
[-- Type: application/octet-stream, Size: 1522 bytes --]
Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com>
---
diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
index 3940726..b703379 100644
--- a/hw/scsi-disk.c
+++ b/hw/scsi-disk.c
@@ -624,7 +624,9 @@ static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag,
{
uint8_t *p;
int page;
-
+ int dbd;
+
+ dbd = buf[1] & 0x8;
page = buf[2] & 0x3f;
DPRINTF("Mode Sense (page %d, len %d)\n", page, len);
p = outbuf;
@@ -635,6 +637,24 @@ static int32_t scsi_send_command(SCSIDevice *d, uint32_t tag,
outbuf[2] = 0x80; /* Readonly. */
}
p += 4;
+ bdrv_get_geometry(s->dinfo->bdrv, &nb_sectors);
+ if ((~dbd) & nb_sectors) {
+ nb_sectors /= s->cluster_size;
+ if (nb_sectors > UINT32_MAX)
+ nb_sectors = UINT32_MAX;
+ nb_sectors--;
+ outbuf[3] = 8; /* Block descriptor length */
+ p[0] = 0; /* media density code */
+ p[1] = (nb_sectors >> 16) & 0xff;
+ p[2] = (nb_sectors >> 8) & 0xff;
+ p[3] = nb_sectors & 0xff;
+ p[4] = 0; /* reserved */
+ p[5] = 0; /* bytes 5-7 are the sector size in bytes */
+ p[6] = s->cluster_size * 2;
+ p[7] = 0;
+ p += 8;
+ }
+
if (page == 4) {
int cylinders, heads, secs;
^ permalink raw reply related [flat|nested] 3+ messages in thread
* RE: [Qemu-devel] [PATCH] scsi disk block descriptor
2009-10-13 20:20 [Qemu-devel] [PATCH] scsi disk block descriptor Artyom Tarasenko
@ 2009-10-13 20:34 ` Krumme, Chris
2009-10-13 21:39 ` Artyom Tarasenko
0 siblings, 1 reply; 3+ messages in thread
From: Krumme, Chris @ 2009-10-13 20:34 UTC (permalink / raw)
To: Artyom Tarasenko, qemu-devel, Blue Swirl
> -----Original Message-----
> From:
> qemu-devel-bounces+chris.krumme=windriver.com@nongnu.org
> [mailto:qemu-devel-bounces+chris.krumme=windriver.com@nongnu.o
> rg] On Behalf Of Artyom Tarasenko
> Sent: Tuesday, October 13, 2009 3:20 PM
> To: qemu-devel; Blue Swirl
> Subject: [Qemu-devel] [PATCH] scsi disk block descriptor
>
> The SCSI-2 documentation suggests, that although the block
> descriptor is optional for an arbitrary SCSI-2 device (chapter 8.2.10,
> http://ldkelley.com/SCSI2/SCSI2/SCSI2/SCSI2/SCSI2-08.html )
> it is mandatory for a disk: chapters 9.1.2, 9.3.3
> ( http://ldkelley.com/SCSI2/SCSI2/SCSI2/SCSI2-09.html ) don't say
> "optional" any more, just "The block descriptor in the MODE SENSE
> data describes the block lengths that are used on the medium."
>
> Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com>
> ---
> diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
> index 3940726..b703379 100644
> --- a/hw/scsi-disk.c
> +++ b/hw/scsi-disk.c
> @@ -624,7 +624,9 @@ static int32_t scsi_send_command(SCSIDevice *d,
> uint32_t tag,
> {
> uint8_t *p;
> int page;
> -
> + int dbd;
> +
> + dbd = buf[1] & 0x8;
> page = buf[2] & 0x3f;
> DPRINTF("Mode Sense (page %d, len %d)\n", page, len);
> p = outbuf;
> @@ -635,6 +637,24 @@ static int32_t scsi_send_command(SCSIDevice *d,
> uint32_t tag,
> outbuf[2] = 0x80; /* Readonly. */
> }
> p += 4;
> + bdrv_get_geometry(s->dinfo->bdrv, &nb_sectors);
> + if ((~dbd) & nb_sectors) {
> + nb_sectors /= s->cluster_size;
> + if (nb_sectors > UINT32_MAX)
> + nb_sectors = UINT32_MAX;
> + nb_sectors--;
> + outbuf[3] = 8; /* Block descriptor length */
> + p[0] = 0; /* media density code */
> + p[1] = (nb_sectors >> 16) & 0xff;
> + p[2] = (nb_sectors >> 8) & 0xff;
> + p[3] = nb_sectors & 0xff;
Hello Artyom,
Above you limit to 32 bits - 1, then you use the bottom 24 bits. Would
it be better to limit to 24 bits - 1, then a drive with more than 24
bits of sectors will show as maximum size rather than a random size?
Thanks
Chris
> + p[4] = 0; /* reserved */
> + p[5] = 0; /* bytes 5-7 are the sector size
> in bytes */
> + p[6] = s->cluster_size * 2;
> + p[7] = 0;
> + p += 8;
> + }
> +
> if (page == 4) {
> int cylinders, heads, secs;
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [Qemu-devel] [PATCH] scsi disk block descriptor
2009-10-13 20:34 ` Krumme, Chris
@ 2009-10-13 21:39 ` Artyom Tarasenko
0 siblings, 0 replies; 3+ messages in thread
From: Artyom Tarasenko @ 2009-10-13 21:39 UTC (permalink / raw)
To: Krumme, Chris; +Cc: Blue Swirl, qemu-devel
2009/10/13 Krumme, Chris <Chris.Krumme@windriver.com>:
>
>
>> -----Original Message-----
>> From:
>> qemu-devel-bounces+chris.krumme=windriver.com@nongnu.org
>> [mailto:qemu-devel-bounces+chris.krumme=windriver.com@nongnu.o
>> rg] On Behalf Of Artyom Tarasenko
>> Sent: Tuesday, October 13, 2009 3:20 PM
>> To: qemu-devel; Blue Swirl
>> Subject: [Qemu-devel] [PATCH] scsi disk block descriptor
>>
>> The SCSI-2 documentation suggests, that although the block
>> descriptor is optional for an arbitrary SCSI-2 device (chapter 8.2.10,
>> http://ldkelley.com/SCSI2/SCSI2/SCSI2/SCSI2/SCSI2-08.html )
>> it is mandatory for a disk: chapters 9.1.2, 9.3.3
>> ( http://ldkelley.com/SCSI2/SCSI2/SCSI2/SCSI2-09.html ) don't say
>> "optional" any more, just "The block descriptor in the MODE SENSE
>> data describes the block lengths that are used on the medium."
>>
>> Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com>
>> ---
>> diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
>> index 3940726..b703379 100644
>> --- a/hw/scsi-disk.c
>> +++ b/hw/scsi-disk.c
>> @@ -624,7 +624,9 @@ static int32_t scsi_send_command(SCSIDevice *d,
>> uint32_t tag,
>> {
>> uint8_t *p;
>> int page;
>> -
>> + int dbd;
>> +
>> + dbd = buf[1] & 0x8;
>> page = buf[2] & 0x3f;
>> DPRINTF("Mode Sense (page %d, len %d)\n", page, len);
>> p = outbuf;
>> @@ -635,6 +637,24 @@ static int32_t scsi_send_command(SCSIDevice *d,
>> uint32_t tag,
>> outbuf[2] = 0x80; /* Readonly. */
>> }
>> p += 4;
>> + bdrv_get_geometry(s->dinfo->bdrv, &nb_sectors);
>> + if ((~dbd) & nb_sectors) {
>> + nb_sectors /= s->cluster_size;
>> + if (nb_sectors > UINT32_MAX)
>> + nb_sectors = UINT32_MAX;
>> + nb_sectors--;
>> + outbuf[3] = 8; /* Block descriptor length */
>> + p[0] = 0; /* media density code */
>> + p[1] = (nb_sectors >> 16) & 0xff;
>> + p[2] = (nb_sectors >> 8) & 0xff;
>> + p[3] = nb_sectors & 0xff;
>
> Hello Artyom,
>
> Above you limit to 32 bits - 1, then you use the bottom 24 bits. Would
> it be better to limit to 24 bits - 1, then a drive with more than 24
> bits of sectors will show as maximum size rather than a random size?
Thanks, Chris!
^ permalink raw reply [flat|nested] 3+ messages in thread
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2009-10-13 20:34 ` Krumme, Chris
2009-10-13 21:39 ` Artyom Tarasenko
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