MTD partition offset info via /proc/mtd & ioctl(MEMGETINFO)

MTD partition offset info via /proc/mtd & ioctl(MEMGETINFO)

[Gopi Palaniappan]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset=us-ascii, Size: 3882 bytes --]


Sorry to mail this again.. I corrected the diff output
in my previous mail

Why doesn't "struct mtd_info" expose partition offset
info so it can be displayed via /proc/mtd?
 
Mak had asked this qn earlier 
http://lists.infradead.org/pipermail/linux-mtd/2004-July/010062.html
 
perhaps his message was not clear... I think he was
asking why /proc/mtd does not display info on
partition offset for each mtd partition.
 
I made a small fix to struct mtd_info, mtdcore.c,
mtdpart.c that adds a new element "offset" to struct
mtd_info...exposing partion offset info from "struct
mtd_part" in mtdpart.c
 
I feel a better solution would be to move the "offset"
element in struct mtd_part into 
struct mtd_info and change all occurances of
"mtd_part->offset" to 
"mtdpart->mtd->offset"
 
Here's the patch I made... 
Please let me know if you have any
comments/suggestions on the patch...or my
suggestion above to move the "offset" element from
mtd_part to mtd_info...
 
===========================================================
 
diff -rc linux2.4.old/drivers/mtd/mtdcore.c
linux2.4/drivers/mtd/mtdcore.c
*** linux2.4.old/drivers/mtd/mtdcore.c  2004-08-08
19:05:05.000000000 -0500
--- linux2.4/drivers/mtd/mtdcore.c      2004-08-08
19:03:17.000000000 -0500
***************
*** 337,344 ****
  
        if (!this)
                return 0;
! 
!       return sprintf(buf, "mtd%d: %8.8x %8.8x
\"%s\"\n", i, this->size,
                       this->erasesize, this->name);
  }
  
--- 337,343 ----
  
        if (!this)
                return 0;
!       return sprintf(buf, "mtd%d: %8.8x %8.8x %8.8x
\"%s\"\n", i, this->offset, this->size,
                       this->erasesize, this->name);
  }
  
***************
*** 355,361 ****
  
        down(&mtd_table_mutex);
  
!       len = sprintf(page, "dev:    size   erasesize 
name\n");
          for (i=0; i< MAX_MTD_DEVICES; i++) {
  
                  l = mtd_proc_info(page + len, i);
--- 354,360 ----
  
        down(&mtd_table_mutex);
  
!       len = sprintf(page, "dev:  offset    size  
erasesize  name\n");
          for (i=0; i< MAX_MTD_DEVICES; i++) {
  
                  l = mtd_proc_info(page + len, i);
diff -rc linux2.4.old/drivers/mtd/mtdpart.c
linux2.4/drivers/mtd/mtdpart.c
*** linux2.4.old/drivers/mtd/mtdpart.c  2004-08-08
19:04:43.000000000 -0500
--- linux2.4/drivers/mtd/mtdpart.c      2004-08-08
19:05:46.000000000 -0500
***************
*** 320,325 ****
--- 320,326 ----
                slave->mtd.eccsize = master->eccsize;
  
                slave->mtd.name = parts[i].name;
+               slave->mtd.offset = parts[i].offset;
                slave->mtd.bank_size =
master->bank_size;
                slave->mtd.module = master->module;
  
diff -rc linux2.4.old/include/linux/mtd.h
linux2.4/include/linux/mtd.h
*** linux2.4.old/include/linux/mtd.h    2004-08-08
19:01:02.000000000 -0500
--- linux2.4/include/linux/mtd.h        2004-08-08
19:07:08.000000000 -0500
***************
*** 69,74 ****
--- 69,75 ----
  struct mtd_info_user {
        u_char type;
        u_int32_t flags;
+       u_int32_t offset;        // Offset to MTD
partition
        u_int32_t size;  // Total size of the MTD
        u_int32_t erasesize;
        u_int32_t oobblock;  // Size of OOB blocks
(e.g. 512)
***************
*** 137,142 ****
--- 138,144 ----
  struct mtd_info {
        u_char type;
        u_int32_t flags;
+       u_int32_t offset;        // Offset to MTD
partition
        u_int32_t size;  // Total size of the MTD
  
        /* "Major" erase size for the device. Nave
users may take this
============================================================
 
 
Thanks,
Gopi
 


---------------------------------
Do you Yahoo!?
Yahoo! Mail is new and improved - Check it out!


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 

MTD partition offset info via /proc/mtd & ioctl(MEMGETINFO)

[Gopi Palaniappan]

I didn't see any comments about my previous posting...
I was wondering if I needed to provide additional
info?

--
Gopi


		
__________________________________
Do you Yahoo!?
Yahoo! Mail - 50x more storage than other providers!
http://promotions.yahoo.com/new_mail

Re: MTD partition offset info via /proc/mtd & ioctl(MEMGETINFO)

[Eric W. Biederman]

Gopi Palaniappan <gpalani1@yahoo.com> writes:

> I didn't see any comments about my previous posting...
> I was wondering if I needed to provide additional
> info?

I had a similar desire. But I wanted the physical starting address of the
mtd devices.

Modify mtd_info_user especially to stick a field in the middle a no-go
that breaks the user space ABI.  And will seriously annoy people.

In talking with Dave we came up with two possible solutions.  Put
the physical starting address into the name so it is displayed in /proc/mtd.
And longer term we can look at using sysfs to export that information.

I have just modified the map drivers amd76xrom and ichxrom to add that
information to the name field of /proc/mtd.

That should be a simple and expedient way to get things moving.
I am puzzled though why you would need partition offset information,
I thought the purpose of partitions was to remove the need for worrying about
offsets into the flash chip.

Eric