[ECOS] Another problem with JFFS2

[Knud Wöhler <knud at festus dot hrz dot uni-oldenburg dot de>]

Hi
I have a problem with JFFS2. If I mount an empty filesystem I got this 
messages:

<5>jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 
0x00000000: 0x2003
instead
<5>jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 
0x00000004: 0x000c
instead
<5>jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 
0x00000008: 0xdc6d
instead
...

I found that the JFFS2 filesystem writes wrong erased block markers to 
the flash. I think it is a compiler problem in erase.c. The values 
(JFFS2_MAGIC_BITMASK, JFFS2_NODETYPE_CLEANMARKER,..) will not be copied 
to the marker structure. In the assembly you can see that the marker 
structure starts at fp-54 but the magic bitmask will be written to fp-68.

I use the gcc 3.2.2 ( xscale platform).


static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct 
jffs2_eraseblock *jeb)
{
...
       jeb->free_size = c->sector_size;
       jeb->used_size = 0;
       jeb->dirty_size = 0;
       jeb->wasted_size = 0;
   } else {
       struct jffs2_unknown_node marker = {
           .magic =    cpu_to_je16(JFFS2_MAGIC_BITMASK),
           .nodetype =    cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER),

404:    e3a03a02     mov    r3, #8192    ; 0x2000
408:    e2833003     add    r3, r3, #3    ; 0x3
40c:    e3a00000     mov    r0, #0    ; 0x0
410:    e50b0040     str    r0, [fp, -#64]
414:    e14b33be     strh    r3, [fp, -#62]
418:    e14b34b0     strh    r3, [fp, -#64]
           .totlen =    cpu_to_je32(c->cleanmarker_size)
41c:    e51b3040     ldr    r3, [fp, -#64]
420:    e597203c     ldr    r2, [r7, #60]
424:    e24b4034     sub    r4, fp, #52    ; 0x34             <- 
Address of 'marker'in r4 (fp - 54)
428:    e50b3034     str    r3, [fp, -#52]
42c:    e3a03d66     mov    r3, #6528    ; 0x1980
430:    e2833005     add    r3, r3, #5    ; 0x5
434:    e50b202c     str    r2, [fp, -#44]
438:    e50b2030     str    r2, [fp, -#48]
43c:    e50b2038     str    r2, [fp, -#56]
440:    e50b203c     str    r2, [fp, -#60]
       };

       marker.hdr_crc = cpu_to_je32(crc32(0, &marker, 
je32_to_cpu(marker.totlen) - 4));
444:    e1a01004     mov    r1, r4                         <- Address 
of 'marker' in r1
448:    e2422004     sub    r2, r2, #4    ; 0x4
44c:    e14b34b4     strh    r3, [fp, -#68]             <- 
JFFS2_MAGIC_BITMASK to 'marker' (fp - 68)
450:    ebfffffe     bl    0 <jffs2_erase_block>

       ret = jffs2_flash_write(c, jeb->offset, 
je32_to_cpu(marker.totlen), &retlen, (char *)&marker);
454:    e598100c     ldr    r1, [r8, #12]
458:    e1a0c000     mov    ip, r0
45c:    e24b3048     sub    r3, fp, #72    ; 0x48
460:    e51b2030     ldr    r2, [fp, -#48]
464:    e1a00007     mov    r0, r7
468:    e50bc02c     str    ip, [fp, -#44]
46c:    e58d4000     str    r4, [sp]
470:    e50bc03c     str    ip, [fp, -#60]
474:    e50bc038     str    ip, [fp, -#56]
478:    ebfffffe     bl    0 <jffs2_erase_block>
       if (ret) {

...
}

If  I change

       struct jffs2_unknown_node marker = {
           .magic =    cpu_to_je16(JFFS2_MAGIC_BITMASK),
           .nodetype =    cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER),
           .totlen =    cpu_to_je32(c->cleanmarker_size)
       };

to

       struct jffs2_unknown_node marker;
       marker.magic =    cpu_to_je16(JFFS2_MAGIC_BITMASK);
       marker.nodetype =    cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER);
       marker.totlen =    cpu_to_je32(c->cleanmarker_size);

all is works fine.

static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct 
jffs2_eraseblock *jeb)
{
...
       struct jffs2_unknown_node marker;
       marker.magic =    cpu_to_je16(JFFS2_MAGIC_BITMASK);
       marker.nodetype =    cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER);
       marker.totlen =    cpu_to_je32(c->cleanmarker_size);
404:    e597303c     ldr    r3, [r7, #60]

//
       marker.hdr_crc = cpu_to_je32(crc32(0, &marker, 
je32_to_cpu(marker.totlen) - 4));
408:    e24b4034     sub    r4, fp, #52    ; 0x34      <- Address of 
'marker'in r4 (fp -52)
40c:    e3a0cd66     mov    ip, #6528    ; 0x1980
410:    e50b3030     str    r3, [fp, -#48]
414:    e51b2030     ldr    r2, [fp, -#48]
418:    e50b3040     str    r3, [fp, -#64]
41c:    e50b303c     str    r3, [fp, -#60]
420:    e3a03a02     mov    r3, #8192    ; 0x2000
424:    e2833003     add    r3, r3, #3    ; 0x3
428:    e28cc005     add    ip, ip, #5    ; 0x5
42c:    e2422004     sub    r2, r2, #4    ; 0x4
430:    e1a01004     mov    r1, r4
434:    e3a00000     mov    r0, #0    ; 0x0
438:    e14bc3b4     strh    ip, [fp, -#52]          <- 
JFFS2_MAGIC_BITMASK (fp - 52)
43c:    e14b33b2     strh    r3, [fp, -#50]
440:    e14b33b8     strh    r3, [fp, -#56]
444:    ebfffffe     bl    0 <jffs2_erase_block>

       ret = jffs2_flash_write(c, jeb->offset, 
je32_to_cpu(marker.totlen), &retlen, (char *)&marker);
448:    e598100c     ldr    r1, [r8, #12]
44c:    e1a0c000     mov    ip, r0
450:    e24b3044     sub    r3, fp, #68    ; 0x44
454:    e51b2030     ldr    r2, [fp, -#48]
458:    e1a00007     mov    r0, r7
45c:    e50bc02c     str    ip, [fp, -#44]
460:    e58d4000     str    r4, [sp]
464:    e50bc03c     str    ip, [fp, -#60]
468:    e50bc040     str    ip, [fp, -#64]
46c:    ebfffffe     bl    0 <jffs2_erase_block>
...
}


Regards,
Knud Wöhler




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