Since we have to write one deletion inode per xattr
into the journal, limit the max number of xattrs.
In theory UBIFS supported up to 65535 xattrs per inode.
But this never worked correctly, expect no powercuts happened.
Now we support only as many xattrs as we can store in 50% of a
LEB.
Even for tiny flashes this allows dozens of xattrs per inode,
which is for an embedded filesystem still fine.
In case someone has existing inodes with much more xattrs, it is
still possible to delete them.
UBIFS will fall back to an non-atomic deletion mode.
Reported-by: Stefan Agner <stefan@agner.ch>
Fixes: 1e51764a3c ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>
With this patch the hashes over the index nodes stored in the tree node
cache are written to flash and are checked when read back from flash.
The hash of the root index node is stored in the master node.
During journal replay the hashes are regenerated from the read nodes
and stored in the tree node cache. This means the nodes must previously
be authenticated by other means. This is done in a later patch.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
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>
CURRENT_TIME_SEC is not y2038 safe. current_time() will be transitioned
to use 64 bit time along with vfs in a separate patch. There is no plan
to transition CURRENT_TIME_SEC to use y2038 safe time interfaces.
current_time() returns timestamps according to the granularities set in
the inode's super_block. The granularity check to call
current_fs_time() or CURRENT_TIME_SEC is not required.
Use current_time() directly to update inode timestamp. Use
timespec_trunc during file system creation, before the first inode is
created.
Link: http://lkml.kernel.org/r/1491613030-11599-9-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Richard Weinberger <richard@nod.at>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As currently new_valid_dev always returns 1, so new_valid_dev check is not
needed, remove it.
Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
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>
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>
We'll need to use the 'next_log_lnum()' helper function from log.c in the fixup
code, so let's move it to misc.h. IOW, this is a preparation to the following
free space fixup changes.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
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>
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>
'ubifs_get_lprops()' and 'ubifs_release_lprops()' basically wrap
mutex lock and unlock. We have them because we want lprops subsystem
be separate and as independent as possible. And we planned better
locking rules for lprops.
Anyway, because they are short, it is better to inline them.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The TNC mutex is unlocked prematurely when reading leaf nodes
with non-hashed keys. This is unsafe because the node may be
moved by garbage collection and the eraseblock unmapped, although
that has never actually happened during stress testing.
This patch fixes the flaw by detecting the race and retrying with
the TNC mutex locked.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
At the moment UBIFS reserves twice old index size space for the
index. But this is not enough in some cases, because if the indexing
node are very fragmented and there are many small gaps, while the
dirty index has big znodes - in-the-gaps method would fail.
Thus, reserve trise as more, in which case we are guaranteed that
we can commit in any case.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
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>
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>
