linux-toradex.git/drivers/mtd/ubi, branch v3.6

UBI: fix a horrible memory deallocation bug

2012-09-04T06:40:26+00:00

UBI was mistakingly using 'kfree()' instead of 'kmem_cache_free()' when
freeing "attach eraseblock" structures in vtbl.c. Thankfully, this happened
only when we were doing auto-format, so many systems were unaffected. However,
there are still many users affected.

It is strange, but the system did not crash and nothing bad happened when
the SLUB memory allocator was used. However, in case of SLOB we observed an
crash right away.

This problem was introduced in 2.6.39 by commit
"6c1e875 UBI: add slab cache for ubi_scan_leb objects"

A note for stable trees:
  Because variable were renamed, this won't cleanly apply to older kernels.
  Changing names like this should help:
	1. ai -> si
	2. aeb_slab_cache -> seb_slab_cache
	3. new_aeb -> new_seb

Reported-by: Richard Genoud 
Tested-by: Richard Genoud 
Tested-by: Artem Bityutskiy 
Cc: stable@vger.kernel.org [v2.6.39+]
Signed-off-by: Artem Bityutskiy

UBI: harmonize the update of ubi->beb_rsvd_pebs

2012-07-18T11:30:34+00:00

Currently, there are several locations where an attempt to reserve more
PEBs for bad PEB handling is made, with the same code being duplicated.

Harmonize it by introducing 'ubi_update_reserved()'.

Also, improve the debug message issued, making it more descriptive.

Artem: amended the patch a little.

Signed-off-by: Shmulik Ladkani 
Signed-off-by: Artem Bityutskiy

UBI: trivial: fix comment of ubi_calculate_reserved function

2012-07-18T10:33:03+00:00

The function name within the comment was not aligned with the actual
function name.

Signed-off-by: Shmulik Ladkani 
Signed-off-by: Artem Bityutskiy

UBI: fix spelling of detach in debug output

2012-07-18T07:13:41+00:00

Signed-off-by: Peter Meerwald 
Signed-off-by: Artem Bityutskiy

UBI: Change the default percentage of reserved PEB

2012-07-18T07:13:41+00:00

The actual value (1%) is too low for actual NAND devices, a huge
majority of device has 2% maximum bad blocks (SLC or MLC).
(Actually it's 20 blocks on a 1024 blocks device, 40/2048...)

Signed-off-by: Richard Genoud

UBI: correct usage of IS_ENABLED()

2012-06-27T11:22:15+00:00

Commit "e9b4cf2 UBI: fix debugfs-less systems support" fixed one
regression but introduced a different regression - the debugfs is now always
compiled out. Root cause: IS_ENABLED() arguments should be used with the
CONFIG_* prefix.

Signed-off-by: Brian Norris 
Signed-off-by: Artem Bityutskiy

UBI: correct ubi_wl_flush locking

2012-06-07T12:22:21+00:00

Commit "62f38455 UBI: modify ubi_wl_flush function to clear work queue for a lnum"
takes the 'work_sem' semaphore in write mode for the entire loop, which is not
very good because it will block other workers for potentially long time. We do
not need to have it in write mode - read mode is enough, and we do not need to
hole it over the entire loop. So this patch turns changes the locking: takes
'work_sem' in read mode and pushes it down to the loop.

Signed-off-by: Artem Bityutskiy

UBI: fix debugfs-less systems support

2012-06-07T07:43:54+00:00

Commit "aa44d1d UBI: remove Kconfig debugging option" broke UBI and it
refuses to initialize if debugfs (CONFIG_DEBUG_FS) is disabled. I incorrectly
assumed that debugfs files creation function will return success if debugfs
is disabled, but they actually return -ENODEV. This patch fixes the issue.

Reported-by: Paul Parsons 
Signed-off-by: Artem Bityutskiy 
Tested-by: Paul Parsons

UBI: modify ubi_wl_flush function to clear work queue for a lnum

2012-05-21T08:34:41+00:00

This patch modifies ubi_wl_flush to force the erasure of
particular volume id / logical eraseblock number pairs. Previous functionality
is preserved when passing UBI_ALL for both values. The locations where ubi_wl_flush
were called are appropriately changed: ubi_leb_erase only flushes for the
erased LEB, and ubi_create_volume forces only flushing for its volume id.
External code can call this new feature via the new function ubi_flush() added
to kapi.c, which simply passes through to ubi_wl_flush().

This was tested by disabling the call to do_work in ubi thread, which results
in the work queue remaining unless explicitly called to remove. UBIFS was
changed to call ubifs_leb_change 50 times for four different LEBs. Then the
new function was called to clear the queue: passing wrong volume ids / lnum,
correct ones, and finally UBI_ALL for both to ensure it was finally all
cleard. The work queue was dumped each time and the selective removal
of the particular LEB numbers was observed. Extra checks were enabled and
ubifs's integck was also run. Finally, the drive was repeatedly filled and
emptied to ensure that the queue was cleared normally.

Artem: amended the patch.

Signed-off-by: Joel Reardon 
Signed-off-by: Artem Bityutskiy

UBI: introduce UBI_ALL constant

2012-05-21T08:34:41+00:00

Joel will use it in his 'ubi_flush()' extention to specify all eraseblocks.
Also amend the comment for UBI_UNKNOWN - it is used beyond attaching info
structure now.

Signed-off-by: Artem Bityutskiy