Commit Graph

15 Commits

Author SHA1 Message Date
Artem Bityutskiy 8d7819b4af UBIFS: lessen amount of debugging check types
We have too many different debugging checks - lessen the amount by merging all
index-related checks into one. At the same time, move the "force in-the-gap"
test to the "index checks" class, because it is too heavy for the "general"
class.

This patch merges TNC, Old index, and Index size check and calles this just
"index checks".

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:28 +03:00
Artem Bityutskiy 2b1844a8c9 UBIFS: introduce helper functions for debugging checks and tests
This patch introduces helper functions for all debugging checks, so instead of
doing

if (!(ubifs_chk_flags & UBIFS_CHK_GEN))

we now do

if (!dbg_is_chk_gen(c))

This is a preparation to further changes where the flags will go away, and
we'll need to only change the helper functions, but the code which utilizes
them won't be touched.

At the same time this patch removes 'dbg_force_in_the_gaps()',
'dbg_force_in_the_gaps_enabled()', and dbg_failure_mode helpers for
consistency.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:28 +03:00
Artem Bityutskiy f42eed7cba UBIFS: harmonize znode flag helpers
We have 3 znode flags: cow, obsolete, dirty. For the last flag we have a
'ubifs_zn_dirty()' helper function, but for the other 2 flags we use
'test_bit()' directly.

This patch makes the situation more consistent and introduces helpers for the
other 2 flags: 'ubifs_zn_cow()' and 'ubifs_zn_obsolete()'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:27 +03:00
Artem Bityutskiy 549c999a76 UBIFS: return EROFS in case of broken commit
If commit failed and it is in broken state, UBIFS switches to R/O mode. Most
operations return -EROFS in this case, except of commit which returns -EINVAL.
Make it return -EROFS too for consistency. This is also important for our power
cut emulation testing.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:26 +03:00
Artem Bityutskiy b137545c44 UBIFS: introduce a separate structure for budgeting info
This patch separates out all the budgeting-related information
from 'struct ubifs_info' to 'struct ubifs_budg_info'. This way the
code looks a bit cleaner. However, the main driver for this is
that we want to save budgeting information and print it later,
so a separate data structure for this is helpful.

This patch is a preparation for the further debugging output
improvements.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13 19:23:53 +03:00
Artem Bityutskiy 8b229c7676 UBIFS: do not read flash unnecessarily
This fix makes the 'dbg_check_old_index()' function return
immediately if debugging is disabled, instead of executing
incorrect 'goto out' which causes UBIFS to:

1. Allocate memory
2. Read the flash

On every commit. OK, we do not commit that often, but it is
still silly to do unneeded I/O anyway.

Credits to coverity for spotting this silly issue.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: stable@kernel.org
2011-04-05 10:39:40 +03:00
Artem Bityutskiy 944fdef52c UBIFS: do not start the commit if there is nothing to commit
This patch fixes suboptimal UBIFS 'sync_fs()' implementation which causes
flash I/O even if the file-system is synchronized. E.g., a 'printk()'
in the MTD erasure function (e.g., 'nand_erase_nand()') can show that
for every 'sync' shell command UBIFS erases at least one eraseblock.

So '$ while true; do sync; done' will cause huge amount of flash I/O.

The reason for this is that UBIFS commits in 'sync_fs()', and starts the
commit even if there is nothing to commit, e.g., it anyway changes the
log. This patch adds a check in the 'do_commit()' UBIFS functions which
prevents the commit if there is nothing to commit.

Reported-by: Hans J. Koch <hjk@linutronix.de>
Tested-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-01-25 10:21:13 +02:00
Artem Bityutskiy 2ef13294d2 UBIFS: introduce new flags for RO mounts
Commit 2fde99cb55 "UBIFS: mark VFS SB RO too"
introduced regression. This commit made UBIFS set the 'MS_RDONLY' flag in the
VFS superblock when it switches to R/O mode due to an error. This was done
to make VFS show the R/O UBIFS flag in /proc/mounts.

However, several places in UBIFS relied on the 'MS_RDONLY' flag and assume this
flag can only change when we re-mount. For example, 'ubifs_put_super()'.

This patch introduces new UBIFS flag - 'c->ro_mount' which changes only when
we re-mount, and preserves the way UBIFS was originally mounted (R/W or R/O).
This allows us to de-initialize UBIFS cleanly in 'ubifs_put_super()'.

This patch also changes all 'ubifs_assert(!c->ro_media)' assertions to
'ubifs_assert(!c->ro_media && !c->ro_mount)', because we never should write
anything if the FS was mounter R/O.

All the places where we test for 'MS_RDONLY' flag in the VFS SB were changed
and now we test the 'c->ro_mount' flag instead, because it preserves the
original UBIFS mount type, unlike the 'MS_RDONLY' flag.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-09-19 21:07:58 +03:00
Artem Bityutskiy 2680d722bf UBIFS: introduce new flag for RO due to errors
The R/O state may have various reasons:

1. The UBI volume is R/O
2. The FS is mounted R/O
3. The FS switched to R/O mode because of an error

However, in UBIFS we have only one variable which represents cases
1 and 3 - 'c->ro_media'. Indeed, we set this to 1 if we switch to
R/O mode due to an error, and then we test it in many places to
make sure that we stop writing as soon as the error happens.

But this is very unclean. One consequence of this, for example, is
that in 'ubifs_remount_fs()' we use 'c->ro_media' to check whether
we are in R/O mode because on an error, and we print a message
in this case. However, if we are in R/O mode because the media
is R/O, our message is bogus.

This patch introduces new flag - 'c->ro_error' which is set when
we switch to R/O mode because of an error. It also changes all
"if (c->ro_media)" checks to "if (c->ro_error)" checks, because
this is what the checks actually mean. We do not need to check
for 'c->ro_media' because if the UBI volume is in R/O mode, we
do not allow R/W mounting, and now writes can happen. This is
guaranteed by VFS. But it is good to double-check this, so this
patch also adds many "ubifs_assert(!c->ro_media)" checks.

In the 'ubifs_remount_fs()' function this patch makes a bit more
changes - it fixes the error messages as well.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-09-17 17:08:09 +03:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Subrata Modak 83ef2ecdbb UBIFS: suppress compilation warning
Fix "using uninitialized variable" compilation warning by using
the "unititialized_var()" helper.

Signed-off-by: Subrata Modak<subrata@linux.vnet.ibm.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-07-24 15:14:54 +03:00
Artem Bityutskiy 17c2f9f85c UBIFS: separate debugging fields out
Introduce a new data structure which contains all debugging
stuff inside. This is cleaner than having debugging stuff
directly in 'c'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:33 +02:00
Artem Bityutskiy 069782a1ee UBIFS: remove printk
Remove the "UBIFS background thread ubifs_bgd0_0 started" message.
We kill the background thread when we switch to R/O mode, and
start it again whan we switch to R/W mode. OLPC is doing this
many times during boot, and we see this message many times as
well, which is irritating. So just kill the message.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-11-06 11:06:14 +02:00
Artem Bityutskiy 014eb04b03 UBIFS: increment commit number earlier
Increment the commit number at the beginnig of the commit, instead
of doing this after the commit. This is needed for further
optimizations.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-08-13 11:27:47 +03:00
Artem Bityutskiy 1e51764a3c UBIFS: add new flash file system
This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.html

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-07-15 17:35:15 +03:00