optimization which makes UBI to use less RAM.
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Merge tag 'upstream-3.8-rc1' of git://git.infradead.org/linux-ubi
Pull UBI update from Artem Bityutskiy:
"Nothing exciting, just clean-ups and nicification. Oh, and one small
optimization which makes UBI to use less RAM."
* tag 'upstream-3.8-rc1' of git://git.infradead.org/linux-ubi:
UBI: embed ubi_debug_info field in ubi_device struct
UBI: introduce helpers dbg_chk_{io, gen}
UBI: replace memcpy with struct assignment
UBI: remove spurious comment
UBI: gluebi: rename misleading variables
UBI: do not allocate the memory unnecessarily
UBI: use list_move_tail instead of list_del/list_add_tail
With this patch code is a bit more readable and there's no
generated code or functionality impact.
Furthermore, this abstracts implementation details and
will allow to change ubi_debug_info in a less invasive way.
Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
As ubi_self_check_all_ff() might sleep we are not allowed
to call it from atomic context.
For now we call it only from ubi_wl_get_peb().
There are some code paths where it would also make sense,
but these paths are currently atomic and only enabled
when fastmap is used.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
If UBI is built without fastmap, get_peb_for_wl() has to
remove the PEB manially from the free tree.
Otherwise the requested PEB lives in two trees.
Reported-by: Zach Sadecki <zsadecki@itwatchdogs.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This line of comment looks completely bogus.
It was introduced in:
commit d99383b00e
Author: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Wed May 18 14:47:34 2011 +0300
UBI: change the interface of a debugging check function
Remove it.
Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
To make fastmap possible the WL sub-system needs some
changes.
Mostly to support fastmaps pools.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch adds fastmap specific data structures to ubi.h.
It moves also struct ubi_work to ubi.h as it is now needed
for more than one c file.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
UBI currently prints a lot of information when it mounts a volume, which
bothers some people. Make it less chatty - print only important information
by default.
Get rid of 'dbg_msg()' macro completely.
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
The existing mechanism of reserving PEBs for bad PEB handling has two
flaws:
- It is calculated as a percentage of good PEBs instead of total PEBs.
- There's no limit on the amount of PEBs UBI reserves for future bad
eraseblock handling.
This patch changes the mechanism to overcome these flaws.
The desired level of PEBs reserved for bad PEB handling (beb_rsvd_level)
is set to the maximum expected bad eraseblocks (bad_peb_limit) minus the
existing number of bad eraseblocks (bad_peb_count).
The actual amount of PEBs reserved for bad PEB handling is usually set
to the desired level (but in some circumstances may be lower than the
desired level, e.g. when attaching to a device that has too few
available PEBs to satisfy the desired level).
In the case where the device has too many bad PEBs (above the expected
limit), then the desired level, and the actual amount of PEBs reserved
are set to zero. No PEBs will be set aside for future bad eraseblock
handling - even if some PEBs are made available (e.g. by shrinking a
volume).
If another PEB goes bad, and there are available PEBs, then the
eraseblock will be marked bad (consuming one available PEB). But if
there are no available PEBs, ubi will go into readonly mode.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
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 <artem.bityutskiy@linux.intel.com>
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>
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>
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>
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>
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>
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>
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>
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>
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>
UBI (and UBIFS) are a bit over-engineered WRT debugging. The idea was to
link as few as possible when debugging is disabled, but the downside is
that most people produce bug reports which are difficult to understand.
This patch weeds out the 'ubi_dbg_dump_stack()' function and turns it
into 'dump_stack()' - it is always useful to have stack dump in case of
an error.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
While looking at a problem reported by UBI around the PEB moving area I
noticed that the 'MOVE_CANCEL_BITFLIPS' is a bit inconsistent name and
'MOVE_TARGET_BITFLIPS' better - let's rename it.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
The 'find_wl_entry()' function expects the maximum difference as the second
argument, not the maximum absolute value. So the "unknown" eraseblock picking
was incorrect, as Shmulik Ladkani spotted. This patch fixes the issue.
Reported-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Cc: stable@kernel.org
The "max" parameter of 'find_wl_entry()' was documented incorrectly and
it actually means the maximum possible difference from the smallest erase
counter. Rename it to "diff" instead, and amend the documentation.
Reported-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
When we fail to erase a PEB, we free the corresponding erase entry object,
but then re-schedule this object if the error code was something like -EAGAIN.
Obviously, it is a bug to use the object after we have freed it.
Reported-by: Emese Revfy <re.emese@gmail.com>
Cc: stable@kernel.org [v2.6.23+]
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Under some cases, when scrubbing the PEB if we did not get the lock on
the PEB it fails to scrub. Add that PEB again to the scrub list
Artem: minor amendments.
Cc: stable@kernel.org [2.6.31+]
Signed-off-by: Bhavesh Parekh <bparekh@nvidia.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
We'll need the 'struct ubi_device *ubi' pointer in every debugging function (to
access the ->dbg field), so add this pointer to all the functions implementing
UBI debugging test modes like 'ubi_dbg_is_bitflip()' etc.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch introduces debugfs support to UBI. All the UBI stuff is kept in the
"ubi" debugfs directory, which contains per-UBI device "ubi/ubiX"
sub-directories, containing debugging files. This file also creates
"ubi/ubiX/chk_gen" and "ubi/ubiX/chk_io" knobs for switching general and I/O
extra checks on and off. And it removes the 'debug_chks' UBI module parameters.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This is a minor preparational patch which changes the
'paranoid_check_in_wl_tree()' function interface by adding the 'ubi' parameter
which will be needed there in the next patch.
And while on it, add "const" qualifier to the 'ubi' parameter of the
'paranoid_check_in_pq()' function.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Fix checkpatch.pl errors and warnings:
* space before tab
* line over 80 characters
* include linux/ioctl.h instead of asm/ioctl.h
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Similarly to the debugging checks and message, make the test modes
be dynamically selected via the "debug_tsts" module parameter or
via the "/sys/module/ubi/parameters/debug_tsts" sysfs file. This
is consistent with UBIFS as well.
And now, since all the Kconfig knobs became dynamic, we can remove
the Kconfig.debug file completely.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch adds a possibility to dynamically switch UBI self-checks
on and off, instead of toggling them compile-time from the configuration
menu. This is much more flexible, and consistent with UBIFS, and this
also simplifies UBI Kconfig menu and the code.
This patch introduces two levels of self-checks - general, which
includes all self-checks which are relatively fast, and I/O, which
includes write-verify checks and erase-verify checks, which are
relatively slow and involve flash I/O.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Currently UBI erases all corrupted eraseblocks, irrespectively of the nature
of corruption: corruption due to power cuts and non-power cut corruption.
The former case is OK, but the latter is not, because UBI may destroy
potentially important data.
With this patch, during scanning, when UBI hits a PEB with corrupted VID
header, it checks whether this PEB contains only 0xFF data. If yes, it is
safe to erase this PEB and it is put to the 'erase' list. If not, this may
be important data and it is better to avoid erasing this PEB. Instead,
UBI puts it to the corr list and moves out of the pool of available PEB.
IOW, UBI preserves this PEB.
Such corrupted PEB lessen the amount of available PEBs. So the more of them
we accumulate, the less PEBs are available. The maximum amount of non-power
cut corrupted PEBs is 8.
This patch is a response to UBIFS problem where reporter
(Matthew L. Creech <mlcreech@gmail.com>) observes that UBIFS index points
to an unmapped LEB. The theory is that corresponding PEB somehow got
corrupted and UBI wiped it. This patch (actually a series of patches)
tries to make sure such PEBs are preserved - this would make it is easier
to analyze the corruption.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Currently UBI has one small flaw - when we read EC or VID header, but find only
0xFF bytes, we return UBI_IO_FF and do not report whether we had bit-flips or
not. In case of the VID header, the scanning code adds this PEB to the free list,
even though there were bit-flips.
Imagine the following situation: we start writing VID header to a PEB and have a
power cut, so the PEB becomes unstable. When we scan and read the PEB, we get
a bit-flip. Currently, UBI would just ignore this and treat the PEB as free. This
patch changes UBI behavior and now UBI will schedule this PEB for erasure.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The 'UBI_IO_PEB_EMPTY' and 'UBI_IO_PEB_FREE' are essentially the same
and mean that there are only 0xFF bytes instead of headers. Simplify
UBI a little by turning them into a single 'UBI_IO_FF' error code.
Also, stop maintaining commentaries in 'ubi_io_read_vid_hdr()' which are
almost identical to commentaries in 'ubi_io_read_ec_hdr()'.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
When an erroneous PEB is scheduling for scrubbing, we end up with the
following oops:
[<c0162404>] (prot_queue_del+0x0/0x50) from [<c01635b4>] (ubi_wl_scrub_peb+0xec/0x13c)
[<c01634c8>] (ubi_wl_scrub_peb+0x0/0x13c) from [<c01603bc>] (ubi_eba_read_leb+0x200/0x428)
[<c01601bc>] (ubi_eba_read_leb+0x0/0x428) from [<c015e3c0>] (ubi_leb_read+0xe8/0x138)
[<c015e2d8>] (ubi_leb_read+0x0/0x138) from [<c00d6918>] (ubifs_start_scan+0x7c/0xf4)
[<c00d689c>] (ubifs_start_scan+0x0/0xf4) from [<c00e3650>] (ubifs_recover_leb+0x3c/0x730)
[<c00e3614>] (ubifs_recover_leb+0x0/0x730) from [<c00e444c>] (ubifs_recover_log_leb+0xc8/0x2dc)
[<c00e4384>] (ubifs_recover_log_leb+0x0/0x2dc) from [<c00d7c20>] (ubifs_replay_journal+0xb90/0x13a4)
[<c00d7090>] (ubifs_replay_journal+0x0/0x13a4) from [<c00cdd68>] (ubifs_fill_super+0xb84/0x1054)
[<c00cd1e4>] (ubifs_fill_super+0x0/0x1054) from [<c00ced04>] (ubifs_get_sb+0xc4/0x2ac)
[<c00cec40>] (ubifs_get_sb+0x0/0x2ac) from [<c007f04c>] (vfs_kern_mount+0x58/0x94)
[<c007eff4>] (vfs_kern_mount+0x0/0x94) from [<c007f0e8>] (do_kern_mount+0x40/0xe8)
[<c007f0a8>] (do_kern_mount+0x0/0xe8) from [<c0095628>] (do_new_mount+0x68/0x8c)
[<c00955c0>] (do_new_mount+0x0/0x8c) from [<c00957a8>] (do_mount+0x15c/0x1b8)
[<c009564c>] (do_mount+0x0/0x1b8) from [<c0095890>] (sys_mount+0x8c/0xd4)
[<c0095804>] (sys_mount+0x0/0xd4) from [<c0023c00>] (ret_fast_syscall+0x0/0x2c)
Kernel panic - not syncing: Fatal exception
The problem is that 'ubi_wl_scrub_peb()' does not expect that PEBs may
be in the erroneous tree, which is a bug. This patch fixes the bug
and adds corresponding check to 'ubi_wl_scrub_peb()'. Now it will simply
ignore erroneous PEBs, instead of causing an oops.
Reported-by: Matthieu CASTET <matthieu.castet@parrot.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI debugging functions were a little bit over-engineered and
returned more error codes than needed, and the callers had to
do useless checks. Simplify the return codes.
Impact: only debugging code is affected, which means that for
non-developers this is a no-op patch.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The 'paranoid_check_empty()' is bogus because, which is easilly
seen on NOR flash, which has long erase cycles, and which may
easilly end-up with half-erased eraseblocks. In this case the
paranoid check fails. I is just wrong to assume that PEBs which
do not have EC headers always contain all 0xFF. Such assumption
should not be made on the I/O level, which is quite low.
Thus, just kill the check.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch adds code which makes sure eraseblocks contain all 0xFF
bytes before starting using them. The verification is done only when
debugging checks are enabled.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
'kmem_cache_free()' oopeses if NULL is passed, and there is
one error-path place where UBI may call it with NULL object.
This problem was pointed to by Adrian Hunter.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
When marking a PEB as bad, print how many PEBs are left reserved.
This is very useful information.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Print not only the PEB number, but also the LEB number and volume id,
which is very useful for bug hunting.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch improves UBI errors handling. ATM UBI switches to
R/O mode when the WL worker fails to read the source PEB.
This means that the upper layers (e.g., UBIFS) has no
chances to unmap the erroneous PEB and fix the error.
This patch changes this behaviour and makes UBI put PEBs
like this into a separate RB-tree, thus preventing the
WL worker from hitting the same read errors again and
again.
But there is a 10% limit on a maximum amount of PEBs like this.
If there are too much of them, UBI switches to R/O mode.
Additionally, this patch teaches UBI not to panic and
switch to R/O mode if after a PEB has been copied, the
target LEB cannot be read back. Instead, now UBI cancels
the operation and schedules the target PEB for torturing.
The error paths has been tested by ingecting errors
into 'ubi_eba_copy_leb()'.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch fixes the error path in the WL worker - in same cases
UBI oopses when 'goto out_error' happens and e1 or e2 are NULL.
This patch also cleans up the error paths a little. And I have
tested nearly all error paths in the WL worker.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
