Commit Graph

40 Commits

Author SHA1 Message Date
Richard Weinberger
6eb61d587f ubifs: Pass struct ubifs_info to ubifs_assert()
This allows us to have more context in ubifs_assert()
and take different actions depending on the configuration.

Signed-off-by: Richard Weinberger <richard@nod.at>
2018-08-15 00:25:21 +02:00
Linus Torvalds
1751e8a6cb Rename superblock flags (MS_xyz -> SB_xyz)
This is a pure automated search-and-replace of the internal kernel
superblock flags.

The s_flags are now called SB_*, with the names and the values for the
moment mirroring the MS_* flags that they're equivalent to.

Note how the MS_xyz flags are the ones passed to the mount system call,
while the SB_xyz flags are what we then use in sb->s_flags.

The script to do this was:

    # places to look in; re security/*: it generally should *not* be
    # touched (that stuff parses mount(2) arguments directly), but
    # there are two places where we really deal with superblock flags.
    FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
            include/linux/fs.h include/uapi/linux/bfs_fs.h \
            security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
    # the list of MS_... constants
    SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
          DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
          POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
          I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
          ACTIVE NOUSER"

    SED_PROG=
    for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done

    # we want files that contain at least one of MS_...,
    # with fs/namespace.c and fs/pnode.c excluded.
    L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')

    for f in $L; do sed -i $f $SED_PROG; done

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-27 13:05:09 -08:00
Rafał Miłecki
1b7fc2c006 ubifs: Use dirty_writeback_interval value for wbuf timer
Right now wbuf timer has hardcoded timeouts and there is no place for
manual adjustments. Some projects / cases many need that though. Few
file systems allow doing that by respecting dirty_writeback_interval
that can be set using sysctl (dirty_writeback_centisecs).

Lowering dirty_writeback_interval could be some way of dealing with user
space apps lacking proper fsyncs. This is definitely *not* a perfect
solution but we don't have ideal (user space) world. There were already
advanced discussions on this matter, mostly when ext4 was introduced and
it wasn't behaving as ext3. Anyway, the final decision was to add some
hacks to the ext4, as trying to fix whole user space or adding new API
was pointless.

We can't (and shouldn't?) just follow ext4. We can't e.g. sync on close
as this would cause too many commits and flash wearing. On the other
hand we still should allow some trade-off between -o sync and default
wbuf timeout. Respecting dirty_writeback_interval should allow some sane
cutomizations if used warily.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:06:24 +01:00
Rafał Miłecki
854826c9d5 ubifs: Drop softlimit and delta fields from struct ubifs_wbuf
Values of these fields are set during init and never modified. They are
used (read) in a single function only. There isn't really any reason to
keep them in a struct. It only makes struct just a bit bigger without
any visible gain.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:06:11 +01:00
Sheng Yong
235c362bd0 UBIFS: extend debug/message capabilities
In the case where we have more than one volumes on different UBI
devices, it may be not that easy to tell which volume prints the
messages.  Add ubi number and volume id in ubifs_msg/warn/error
to help debug. These two values are passed by struct ubifs_info.

For those where ubifs_info is not initialized yet, ubifs_* is
replaced by pr_*. For those where ubifs_info is not avaliable,
ubifs_info is passed to the calling function as a const parameter.

The output looks like,

[   95.444879] UBIFS (ubi0:1): background thread "ubifs_bgt0_1" started, PID 696
[   95.484688] UBIFS (ubi0:1): UBIFS: mounted UBI device 0, volume 1, name "test1"
[   95.484694] UBIFS (ubi0:1): LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[   95.484699] UBIFS (ubi0:1): FS size: 30220288 bytes (28 MiB, 238 LEBs), journal size 1523712 bytes (1 MiB, 12 LEBs)
[   95.484703] UBIFS (ubi0:1): reserved for root: 1427378 bytes (1393 KiB)
[   95.484709] UBIFS (ubi0:1): media format: w4/r0 (latest is w4/r0), UUID 40DFFC0E-70BE-4193-8905-F7D6DFE60B17, small LPT model
[   95.489875] UBIFS (ubi1:0): background thread "ubifs_bgt1_0" started, PID 699
[   95.529713] UBIFS (ubi1:0): UBIFS: mounted UBI device 1, volume 0, name "test2"
[   95.529718] UBIFS (ubi1:0): LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[   95.529724] UBIFS (ubi1:0): FS size: 19808256 bytes (18 MiB, 156 LEBs), journal size 1015809 bytes (0 MiB, 8 LEBs)
[   95.529727] UBIFS (ubi1:0): reserved for root: 935592 bytes (913 KiB)
[   95.529733] UBIFS (ubi1:0): media format: w4/r0 (latest is w4/r0), UUID EEB7779D-F419-4CA9-811B-831CAC7233D4, small LPT model

[  954.264767] UBIFS error (ubi1:0 pid 756): ubifs_read_node: bad node type (255 but expected 6)
[  954.367030] UBIFS error (ubi1:0 pid 756): ubifs_read_node: bad node at LEB 0:0, LEB mapping status 1

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2015-03-25 11:08:41 +02:00
Fabian Frederick
39274a1e8d UBIFS: kernel-doc warning fix
s/data/timer

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2014-07-19 09:53:52 +03:00
Daniel Golle
90bea5a3f0 UBIFS: respect MS_SILENT mount flag
When attempting to mount a non-ubifs formatted volume, lots of error
messages (including a stack dump) are thrown to the kernel log even if
the MS_SILENT mount flag is set.
Fix this by introducing adding an additional state-variable in
struct ubifs_info and suppress error messages in ubifs_read_node if
MS_SILENT is set.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2014-06-02 18:00:52 +03:00
Richard Weinberger
b36a261e8c UBI: Kill data type hint
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>
2012-05-20 20:25:59 +03:00
Artem Bityutskiy
edf6be245f UBIFS: rename dumping functions
This commit re-names all functions which dump something from "dbg_dump_*()" to
"ubifs_dump_*()". This is done for consistency with UBI and because this way it
will be more logical once we remove the debugging sompilation option.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-16 19:15:56 +03:00
Artem Bityutskiy
7c46d0ae29 UBIFS: get rid of dbg_dump_stack
In case of errors we almost always need the stack dump - it makes no sense
to compile it out. Remove the 'dbg_dump_stack()' function completely.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-16 19:04:54 +03:00
Artem Bityutskiy
f57cb188cc UBIFS: remove custom list of superblocks
This is a clean-up of the power-cut emulation code - remove the custom list of
superblocks which we maintained to find the superblock by the UBI volume
descriptor. We do not need that crud any longer, because now we can get the
superblock as a function argument.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:33 +03:00
Artem Bityutskiy
987226a5d3 UBIFS: switch to ubifs_leb_write
Stop using 'ubi_leb_write()' directly and switch to the 'ubifs_leb_write()'
helper.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:33 +03:00
Artem Bityutskiy
d304820a1f UBIFS: switch to ubifs_leb_read
Instead of using 'ubi_read()' function directly, used the 'ubifs_leb_read()'
helper function instead. This allows to get rid of several redundant error
messages and make sure that we always have a stack dump on read errors.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:33 +03:00
Artem Bityutskiy
83cef708c6 UBIFS: introduce more I/O helpers
Introduce the following I/O helper functions: 'ubifs_leb_read()',
'ubifs_leb_write()', 'ubifs_leb_change()', 'ubifs_leb_unmap()',
'ubifs_leb_map()', 'ubifs_is_mapped().

The idea is to wrap all UBI I/O functions in order to encapsulate various
assertions and error path handling (error message, stack dump, switching to R/O
mode). And there are some other benefits of this which will be used in the
following patches.

This patch does not switch whole UBIFS to use these functions yet.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:33 +03:00
Artem Bityutskiy
d033c98b17 UBIFS: always print stacktrace when switching to R/O mode
When switching to R/O mode due to an I/O error, always dump the stack, not only
when debugging is enabled.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04 10:54:33 +03:00
Ben Gardiner
4f1ab9b01d UBIFS: assert no fixup when writing a node
The current free space fixup can result in some writing to the UBI volume
when the space_fixup flag is set.

To catch instances where UBIFS is writing to the NAND while the space_fixup
flag is set, add an assert to ubifs_write_node().

Artem: tweaked the patch, added similar assertion to the write buffer
       write path.

Signed-off-by: Ben Gardiner <bengardiner@nanometrics.ca>
Reviewed-by: Matthew L. Creech <mlcreech@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-06-03 18:12:31 +03:00
Artem Bityutskiy
cb14a18465 UBIFS: synchronize write-buffer before switching to the next bud
Currently when UBIFS fills up the current bud (which is the last in the journal
head) and switches to the next bud, it first writes the log reference node for
the next bud and only after this synchronizes the write-buffer of the previous
bud. This is not a big deal, but an unclean power cut may lead to a situation
when we have corruption in a next-to-last bud, although it is much more logical
that we have to have corruption only in the last bud.

This patch also removes write-buffer synchronization from
'ubifs_wbuf_seek_nolock()' because this is not needed anymore (we synchronize
the write-buffer explicitly everywhere now) and also because this is just
prone to various errors.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-16 10:31:41 +03:00
Artem Bityutskiy
12f338914e UBIFS: remove unnecessary stack variable
This is patch removes an unnecessary 'offs' variable from 'ubifs_wbuf_write_nolock()'
- we can just keep 'wbuf->offs' up-to-date instead. This patch is very minor
the only motivation for it was that it is cleaner to keep wbuf->offs up-to-date
by the time we call 'ubifs_leb_write()'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-16 10:31:40 +03:00
Artem Bityutskiy
c43615702f UBIFS: fix minor stylistic issues
Fix several minor stylistic issues:
* lines longer than 80 characters
* space before closing parenthesis ')'
* spaces in the indentations

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13 19:23:53 +03:00
Artem Bityutskiy
6c7f74f703 UBIFS: use max_write_size for write-buffers
Switch write-buffers from 'c->min_io_size' to 'c->max_write_size' which
presumably has to be more write speed-efficient. However, when write-buffer
is synchronized, write only the the min. I/O units which contain the
data, do not write whole write-buffer. This is more space-efficient.

Additionally, this patch takes into account that the LEB might not start
from the max. write unit-aligned address.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-08 10:12:49 +02:00
Artem Bityutskiy
3c89f396dc UBIFS: introduce write-buffer size field
Currently we assume write-buffer size is always min_io_size. But
this is about to change and write-buffers may be of variable size.
Namely, they will be of max_write_size at the beginning, but will
get smaller when we are approaching the end of LEB.

This is a preparation patch which introduces 'size' field in
the write-buffer structure which carries the current write-buffer
size.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-08 10:12:49 +02:00
Artem Bityutskiy
18d1d7fbcc UBIFS: introduce mounting flag
This is a preparational patch which removes the 'c->always_chk_crc' which was
set during mounting and remounting to R/W mode and introduces 'c->mounting'
flag which is set when mounting. Now the 'c->always_chk_crc' flag is the
same as 'c->remounting_rw && c->mounting'.

This patch is a preparation for the next one which will need to know when we
are mounting and remounting to R/W mode, which is exactly what
'c->always_chk_crc' effectively is, but its name does not suite the
next patch. The other possibility would be to just re-name it, but then
we'd end up with less logical flags coverage.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-01-17 23:24:30 +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
Artem Bityutskiy
3a8fa0ed3e UBIFS: improve error reporting when reading bad node
When an error happens during validation of read node, the typical situation is that
the LEB we read is unmapped (due to some bug). It is handy to include the mapping
status into the error message.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-08-30 10:19:09 +03:00
ZhangJieJing
2fde99cb55 UBIFS: mark VFS SB RO too
If some read/write error happens (eg.CRC error), UBIFS swotches to
read-only mode, but the VFS infomation still not update.
This patch add this also make /proc/mounts update.

Signed-off-by: Zhang Jiejing <kzjeef@gmail.com>
2010-04-29 15:12:18 +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
Artem Bityutskiy
77a7ae580c UBIFS: improve journal head debugging prints
Convert the journal head integer into the head name when printing
debugging information.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-09-15 17:05:06 +03:00
Adrian Hunter
4473758944 UBIFS: fix 64-bit divisions in debug print
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
2009-07-05 18:45:18 +03:00
Artem Bityutskiy
cb54ef8b13 UBIFS: few spelling fixes
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-07-05 18:45:18 +03:00
Artem Bityutskiy
2a35a3a8ab UBIFS: set write-buffer timout to 3-5 seconds
This patch cleans up write-buffer timeout initialization and
sets it to 3-5 interval.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-07-05 18:45:17 +03:00
Artem Bityutskiy
0b335b9d7d UBIFS: slightly optimize write-buffer timer usage
This patch adds the following minor optimization:

1. If write-buffer does not use the timer, indicate it with the
   wbuf->no_timer variable, instead of using the wbuf->softlimit
   variable. This is better because wbuf->softlimit is of ktime_t
   type, and the ktime_to_ns function contains 64-bit multiplication.

2. Do not call the 'hrtimer_cancel()' function for write-buffers
   which do not use timers.

3. Do not cancel the timer in 'ubifs_put_super()' because the
   synchronization function does this.

This patch also removes a confusing comment.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-07-05 18:45:16 +03:00
Artem Bityutskiy
70aee2f153 UBIFS: improve debugging messaged
1. Make the I/O debugging message print the journal head number.
2. Add prints to timer functions.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-07-05 18:45:16 +03:00
Adrian Hunter
e3dc5a665d UBIFS: fix integer overflow warning
Fix the following warning:

fs/ubifs/io.c: In function 'ubifs_wbuf_init':
fs/ubifs/io.c:860: warning: integer overflow in expression

And limit maximum hrtimer delta to ULONG_MAX because the
argument is 'unsigned long'.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-07-05 18:45:15 +03:00
Artem Bityutskiy
f2c5dbd7b7 UBIFS: start using hrtimers
UBIFS uses timers for write-buffer write-back. It is not
crucial for us to write-back exactly on time. We are fine
to write-back a little earlier or later. And this means
we may optimize UBIFS timer so that it could be groped
with a close timer event, so that the CPU would not be
waken up just to do the write back. This is optimization
to lessen power consumption, which is important in
embedded devices UBIFS is used for.

hrtimers have a nice feature: they are effectively range
timers, and we may defind the soft and hard limits for
it. Standard timers do not have these feature. They may
only be made deferrable, but this means there is effectively
no hard limit. So, we will better use hrtimers.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-06-08 11:14:58 +03:00
Artem Bityutskiy
6f7ab6d458 UBIFS: fix no_chk_data_crc
When data CRC checking is disabled, UBIFS returns incorrect return
code from the 'try_read_node()' function (0 instead of 1, which means
CRC error), which make the caller re-read the data node again, but using
a different code patch, so the second read is fine. Thus, we read the
same node twice. And the result of this is that UBIFS is slower
with no_chk_data_crc option than it is with chk_data_crc option.
This patches fixes the problem.

Reported-by: Reuben Dowle <Reuben.Dowle@navico.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-01-27 16:25:10 +02:00
Artem Bityutskiy
ccb3eba724 UBIFS: check data CRC when in error state
When UBIFS switches to R/O mode because of an error,
it is reasonable to enable data CRC checking.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-09-30 11:12:57 +03:00
Adrian Hunter
2953e73f1c UBIFS: add no_chk_data_crc mount option
UBIFS read performance can be improved by skipping the CRC
check when data nodes are read.  This option can be used if
the underlying media is considered to be highly reliable.
Note that CRCs are always checked for metadata.

Read speed on Arm platform with OneNAND goes from 19 MiB/s
to 27 MiB/s with data CRC checking disabled.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-09-30 11:12:56 +03:00
Adrian Hunter
ff46d7b3e0 UBIFS: make ubifs_ro_mode() not inline
We use ubifs_ro_mode() quite a lot, and not in fast-path, so
there is no reason to blow the code up by having it inlined.
Also, we usually want R/O mode change to be seen to other
CPUs as soon as possible, so when we make this a function
call, we will automatically have a memory barrier.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-08-13 11:24:26 +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