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 <reardonj@inf.ethz.ch>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

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 <artem.bityutskiy@linux.intel.com>

This is part of a multipart patch to allow UBI to force the erasure of
particular logical eraseblock numbers. In this patch, the volume id and LEB
number are added to ubi_work data structure, and both are also passed as a
parameter to schedule erase to set it appropriately. Whenever ubi_wl_put_peb
is called, the lnum is also passed to be forwarded to schedule erase. Later,
a new ubi_sync_lnum will be added to execute immediately all work related to
that lnum.

This was tested by outputting the vol_id and lnum during the schedule of
erasure. The ubi thread was disabled and two ubifs drives on separate
partitions repeated changed a small number of LEBs. The ubi module was readded,
and all the erased LEBs, corresponding to the volumes, were added to the
schedule erase queue.

Artem: minor tweaks
Signed-off-by: Joel Reardon <reardonj@inf.ethz.ch>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

This patch adds the volume id to struct ubi_ainf_peb when scanning the LEBs at
startup. PEBs now added to the erase queue will know their original LEB number
and volume id, if available, and will be -1 otherwise (for instance, if the VID
header is unreadable).

This was tested by creating an ubi device with 3 volumes and disabiling the
ubi_thread's do_work functionality. The different ubi volumes were formatted
to ubifs and had files created and erased.  The ubi modules was reloaded and
the list of LEB's added to the erased list was outputted, confirming the
volume ids and LEB numbers were appropriate.
Signed-off-by: Joel Reardon <reardonj@inf.ethz.ch>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Explicitly provide the first internal volume ID value in the comment for
UBI_INTERNAL_VOL_START. This allows developers who, when adding features
related to volume ids and observe unexpected very large volume ids, to grep
for the observed value in the source code and find out immediately that it is
expected behaviour.
Signed-off-by: Joel Reardon <reardonj@inf.ethz.ch>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Finally, rename the scan.c file. Now adding fastmap support won't look that
hacky anymore.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

This file is small and it does not make sense to have it separate from where
everything else lives, so merge it with ubi.h.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Rename the constant to UBI_UNKNOWN, for the same reason that we are going
to add nother attaching method and re-use the same data structures, so the
"SCAN" in the name becomes incorrect. I've also removed the "_EC" part because
Joel is going to use this constant for other fields in the attaching info data
structures.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Rename the 'attach_by_scanning()' function to 'ubi_attach()' and move it to
scan.c. Richard will plug his fastmap stuff there.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

We have a couple of initialization funcntionsn left which have "_scan" suffic -
rename them:

ubi_eba_init_scan() -> ubi_eba_init()
ubi_wl_init_scan() -> ubi_wl_init()
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

This patch amends commentaries in scan.[ch] to match the new logic. Reminder -
we did the restructuring to prepare the code for adding the fastmap. This patch
also renames a couple of functions - it was too difficult to separate out that
change and I decided that it is not too bad to have it in the same patch with
commentaries changes.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The old name is not logical anymore - rename it to 'aeb_slab_cache'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The old name is not logical anymore - rename it to 'ubi_move_aeb_to_list()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The old name is not logical anymore - rename it to 'ubi_destroy_ai()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The old name is not logical anymore - rename it to 'ubi_early_get_peb()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The old name is not logical anymore - rename it to 'ubi_remove_av()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The old name is not logical anymore - rename it to 'ubi_find_av()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The old name is not logical anymore - rename it to 'ubi_add_to_av()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The 'ubi_scan_find_aeb()' function is unused and thus can be removed.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

The 'ubi_scan_erase_peb()' is used only in scan.c so can be static. Also
re-name it to 'early_erase_peb()' because we tend to use "ubi_" prefix only for
non-static fuction and also because the new name is better.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

After re-naming the 'struct ubi_scan_volume' we should adjust all variables
named 'sv' to something else, because 'sv' stands for "scanning volume".
Let's rename it to 'av' which stands for "attaching volume" which is
a bit more consistent and has the same length, which makes re-naming easy.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

After re-naming the 'struct ubi_scan_info' we should adjust all variables
named 'si' to something else, because 'si' stands for "scanning info".
Let's rename it to 'ai' which stands for "attaching info" which is
a bit more consistent and has the same length, which makes re-naming easy.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

After re-naming the 'struct ubi_scan_leb' we should adjust all variables
named 'seb' to something else, because 'seb' stands for "scanning eraseblock".
Let's rename it to 'aeb' which stands for "attaching eraseblock" which is
a bit more consistend and has the same length.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

Now some commentaries are out-of-date, after we re-named the data
structures - amend them.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

Rename 'struct ubi_scan_info' to 'struct ubi_attach_info'. This is part
of the code re-structuring I am trying to do in order to add fastmap
in a more logical way. Fastmap can share a lot with scanning, including
the attach-time data structures, which all now have "scan" word in the
name. Let's get rid of this word.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

Rename 'struct ubi_scan_volume' to 'struct ubi_ainf_volume'. This is part
of the code re-structuring I am trying to do in order to add fastmap
in a more logical way. Fastmap can share a lot with scanning, including
the attach-time data structures, which all now have "scan" word in the
name. Let's get rid of this word and use "ainf" instead which stands
for "attach information". It has the same length as "scan" so re-naming
is trivial.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

Rename 'struct ubi_scan_leb' to 'struct ubi_ainf_leb'. This is part
of the code re-structuring I am trying to do in order to add fastmap
in a more logical way. Fastmap can share a lot with scanning, including
the attach-time data structures, which all now have "scan" word in the
name. Let's get rid of this word and use "ainf" instead which stands
for "attach information". It has the same length as "scan" so re-naming
is trivial.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

This patch removes the 'dbg_err()' macro and we now use 'ubi_err' instead.
The idea of 'dbg_err()' was to compile out some error message to make the
binary a bit smaller - but I think it was a bad idea.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

We have the "sefl-check" feature in UBI, but for historical reasons many
corresponding functions and commentaries in the code use term "paranoid check"
instead. Let's clean this up and use "self-check" everywhere.

This patch renames functions, amends messages and kills several redundant
debugging messages.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

We have the "sefl-check" feature in UBI, but for historical reasons many
corresponding functions and commentaries in the code use term "paranoid check"
instead. Let's clean this up and use "self-check" everywhere.

This patch renames functions, amends comments and messages. It touches only the
io.c file.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

This patch kills the UBI debugging Kconfig option completely and makes all the
debugging stuff to be always compiled-in. It was pain in the neck to maintain
this useless option because all users I am aware of have debugging enabled
anyway - how else will you diagnose errors otherwise?
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_mkvol_req()' to 'ubi_dump_mkvol_req()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_seb()' to 'ubi_dump_seb()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_sv()' to 'ubi_dump_sv()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_vtbl_record()' to 'ubi_dump_vtbl_record()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_vol_info()' to 'ubi_dump_vol_info()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Richard removed the "dtype" hint, but few commentaries were left and this patch
removes them. I've also added a better description about the "dtype" field in
the ubi-user.h for people who may ever wonder what was that dtype thing about.

This patch also adds an important note that it is better to use value "3" for
the "dtype" field.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

This finally removes the data type hint from the UBI ABI.
>From now on the "dtype" field will be ignored and must not used
anymore.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

We do not need this feature and to our shame it even was not working
and there was a bug found very recently.
	-- Artem Bityutskiy

Without the data type hint UBI2 (fastmap) will be easier to implement.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>