Split off part of dquot_quota_sync() which writes dquots into a quota file
to a separate function. In the next patch we will use the function from
filesystems and we do not want to abuse ->quota_sync quotactl callback more
than necessary.
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In principle, a filesystem may want to have ->sync_fs() called during sync(1)
although it does not have a bdi (i.e. s_bdi is set to noop_backing_dev_info).
Only writeback code really needs bdi set to something reasonable. So move the
checks where they are more logical.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch makes UFS stop using the VFS '->write_super()' method along with
the 's_dirt' superblock flag, because they are on their way out.
The way we implement this is that we schedule a delay job instead relying on
's_dirt' and '->write_super()'.
The whole "superblock write-out" VFS infrastructure is served by the
'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and
writes out all dirty superblocks using the '->write_super()' call-back. But the
problem with this thread is that it wastes power by waking up the system every
5 seconds, even if there are no diry superblocks, or there are no client
file-systems which would need this (e.g., btrfs does not use
'->write_super()'). So we want to kill it completely and thus, we need to make
file-systems to stop using the '->write_super()' VFS service, and then remove
it together with the kernel thread.
Tested using fsstress from the LTP project.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch does not do any functional changes. It only moves 3 functions
in fs/ufs/super.c a little bit up in order to prepare for further changes
where I'll need this new arrangement to avoid forward declarations.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
UFS calls 'ufs_write_super()' from 'ufs_put_super()' in order to write the
superblocks to the media. However, it is not needed because VFS calls
'->sync_fs()' before calling '->put_super()' - so by the time we are in
'ufs_write_super()', the superblocks are already synchronized.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
It does not look like sysv FS needs 'write_super()' at all, because all it
does is a timestamp update. I cannot test this patch, because this
file-system is so old and probably has not been used by anyone for years,
so there are no tools to create it in Linux. But from the code I see that
marking the superblock as dirty is basically marking the superblock buffers as
drity and then setting the s_dirt flag. And when 'write_super()' is executed to
handle the s_dirt flag, we just update the timestamp and again mark the
superblock buffer as dirty. Seems pointless.
It looks like we can update the timestamp more opprtunistically - on unmount
or remount of sync, and nothing should change.
Thus, this patch removes 'sysv_write_super()' and 's_dirt'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We do not need to call 'sysv_write_super()' from 'sysv_remount()',
because VFS has called 'sysv_sync_fs()' before calling '->remount()'.
So remove it. Remove also '(un)lock_super()' which obvioulsy is becoming
useless in this function.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We do not need to call 'sysv_write_super()' from 'sysv_put_super()',
because VFS has called 'sysv_sync_fs()' before calling '->put_super()'.
So remove it.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch makes hfs stop using the VFS '->write_super()' method along with
the 's_dirt' superblock flag, because they are on their way out.
The whole "superblock write-out" VFS infrastructure is served by the
'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and
writes out all dirty superblocks using the '->write_super()' call-back. But the
problem with this thread is that it wastes power by waking up the system every
5 seconds, even if there are no diry superblocks, or there are no client
file-systems which would need this (e.g., btrfs does not use
'->write_super()'). So we want to kill it completely and thus, we need to make
file-systems to stop using the '->write_super()' VFS service, and then remove
it together with the kernel thread.
Tested using fsstress from the LTP project.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add an 'sb' VFS superblock back-reference to the 'struct hfs_sb_info' data
structure - we will need to find the VFS superblock from a
'struct hfs_sb_info' object in the next patch, so this change is jut a
preparation.
Remove few useless newlines while on it.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We have the following pattern in 2 places in HFS
if (!RDONLY)
hfs_mdb_commit();
This patch pushes the RDONLY check down to 'hfs_mdb_commit()'. This will
make the following patches a bit simpler.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
HFS calls 'hfs_write_super()' from 'hfs_put_super()' in order to write the MDB
to the media. However, it is not needed because VFS calls '->sync_fs()' before
calling '->put_super()' - so by the time we are in 'hfs_write_super()', the MDB
is already synchronized.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Stop using lock_super for serializing the MDB changes - use the buffer-head own
lock instead. Tested with fsstress.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
HFS uses 'lock_super()'/'unlock_super()' around 'hfs_mdb_commit()' in order
to serialize MDB (Master Directory Block) changes. Push it down to
'hfs_mdb_commit()' in order to simplify the code a bit.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch makes hfsplus stop using the VFS '->write_super()' method along with
the 's_dirt' superblock flag, because they are on their way out.
The whole "superblock write-out" VFS infrastructure is served by the
'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and
writes out all dirty superblocks using the '->write_super()' call-back. But the
problem with this thread is that it wastes power by waking up the system every
5 seconds, even if there are no diry superblocks, or there are no client
file-systems which would need this (e.g., btrfs does not use
'->write_super()'). So we want to kill it completely and thus, we need to make
file-systems to stop using the '->write_super()' VFS service, and then remove
it together with the kernel thread.
Tested using fsstress from the LTP project.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This check is useless because we always have 'sb->s_fs_info' to be non-NULL.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Print correct function name in the debugging print of the
'hfsplus_sync_fs()' function.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
... because it is used only in fs/hfsplus/super.c.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
... and schedule_work() for interrupt/kernel_thread callers
(and yes, now it *is* OK to call from interrupt).
We are guaranteed that __fput() will be done before we return
to userland (or exit). Note that for fput() from a kernel
thread we get an async behaviour; it's almost always OK, but
sometimes you might need to have __fput() completed before
you do anything else. There are two mechanisms for that -
a general barrier (flush_delayed_fput()) and explicit
__fput_sync(). Both should be used with care (as was the
case for fput() from kernel threads all along). See comments
in fs/file_table.c for details.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This function is entirely trivial and only has one caller, so remove it to
simplify the code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Add a XFS_ prefix to IO_DIRECT,XFS_IO_DELALLOC, XFS_IO_UNWRITTEN and
XFS_IO_OVERWRITE. This to avoid namespace conflict with other modules.
Signed-off-by: Alain Renaud <arenaud@sgi.com>
Reviewed-by: Rich Johnston <rjohnston@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
There is no need to keep this helper around, opencoding it in the only
caller is just as clear.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
All callers of xfs_imap_to_bp want the dinode pointer, so let's calculate it
inside xfs_imap_to_bp. Once that is done xfs_itobp becomes a fairly pointless
wrapper which can be replaced with direct calls to xfs_imap_to_bp.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
We need to zero out part of a page which beyond EOF before setting uptodate,
otherwise, mapread or write will see non-zero data beyond EOF.
Based on the code in fs/buffer.c and the following ext4 commit:
ext4: handle EOF correctly in ext4_bio_write_page()
And yes, I wish we had a good test case for it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Use this new method to replace our hacky use of ->dirty_inode. An additional
benefit is that we can now propagate errors up the stack.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Fix trivial typo error that has written "It" to "Is".
Signed-off-by: Chen Baozi <baozich@gmail.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Pull pnfs/ore fixes from Boaz Harrosh:
"These are catastrophic fixes to the pnfs objects-layout that were just
discovered. They are also destined for @stable.
I have found these and worked on them at around RC1 time but
unfortunately went to the hospital for kidney stones and had a very
slow recovery. I refrained from sending them as is, before proper
testing, and surly I have found a bug just yesterday.
So now they are all well tested, and have my sign-off. Other then
fixing the problem at hand, and assuming there are no bugs at the new
code, there is low risk to any surrounding code. And in anyway they
affect only these paths that are now broken. That is RAID5 in pnfs
objects-layout code. It does also affect exofs (which was not broken)
but I have tested exofs and it is lower priority then objects-layout
because no one is using exofs, but objects-layout has lots of users."
* 'for-linus' of git://git.open-osd.org/linux-open-osd:
pnfs-obj: Fix __r4w_get_page when offset is beyond i_size
pnfs-obj: don't leak objio_state if ore_write/read fails
ore: Unlock r4w pages in exact reverse order of locking
ore: Remove support of partial IO request (NFS crash)
ore: Fix NFS crash by supporting any unaligned RAID IO
http://lists.infradead.org/pipermail/linux-mtd/2012-May/041408.htmlhttp://lists.infradead.org/pipermail/linux-mtd/2012-June/042422.html
and we finally have the fix. I am quite confident the fix is correct
because I could reproduce the problem with nandsim and verify the
fix. It was also verified by Iwo (the reporter).
I am also confident that this is OK to merge the fix so late because
this patch affects only the fixup functionality, which is not used by
most users.
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Merge tag 'upstream-3.5-rc8' of git://git.infradead.org/linux-ubifs
Pull UBIFS free space fix-up bugfix from Artem Bityutskiy:
"It's been reported already twice recently:
http://lists.infradead.org/pipermail/linux-mtd/2012-May/041408.htmlhttp://lists.infradead.org/pipermail/linux-mtd/2012-June/042422.html
and we finally have the fix. I am quite confident the fix is correct
because I could reproduce the problem with nandsim and verify the fix.
It was also verified by Iwo (the reporter).
I am also confident that this is OK to merge the fix so late because
this patch affects only the fixup functionality, which is not used by
most users."
* tag 'upstream-3.5-rc8' of git://git.infradead.org/linux-ubifs:
UBIFS: fix a bug in empty space fix-up
This patch removes the 64-bit divides introduced in the previous patch
in favor of shifting, so that it will compile properly on 32-bit machines.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
It is very common for the end of the file to be unaligned on
stripe size. But since we know it's beyond file's end then
the XOR should be preformed with all zeros.
Old code used to just read zeros out of the OSD devices, which is a great
waist. But what scares me more about this situation is that, we now have
pages attached to the file's mapping that are beyond i_size. I don't
like the kind of bugs this calls for.
Fix both birds, by returning a global zero_page, if offset is beyond
i_size.
TODO:
Change the API to ->__r4w_get_page() so a NULL can be
returned without being considered as error, since XOR API
treats NULL entries as zero_pages.
[Bug since 3.2. Should apply the same way to all Kernels since]
CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
The read-4-write pages are locked in address ascending order.
But where unlocked in a way easiest for coding. Fix that,
locks should be released in opposite order of locking, .i.e
descending address order.
I have not hit this dead-lock. It was found by inspecting the
dbug print-outs. I suspect there is an higher lock at caller that
protects us, but fix it regardless.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Do to OOM situations the ore might fail to allocate all resources
needed for IO of the full request. If some progress was possible
it would proceed with a partial/short request, for the sake of
forward progress.
Since this crashes NFS-core and exofs is just fine without it just
remove this contraption, and fail.
TODO:
Support real forward progress with some reserved allocations
of resources, such as mem pools and/or bio_sets
[Bug since 3.2 Kernel]
CC: Stable Tree <stable@kernel.org>
CC: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
In RAID_5/6 We used to not permit an IO that it's end
byte is not stripe_size aligned and spans more than one stripe.
.i.e the caller must check if after submission the actual
transferred bytes is shorter, and would need to resubmit
a new IO with the remainder.
Exofs supports this, and NFS was supposed to support this
as well with it's short write mechanism. But late testing has
exposed a CRASH when this is used with none-RPC layout-drivers.
The change at NFS is deep and risky, in it's place the fix
at ORE to lift the limitation is actually clean and simple.
So here it is below.
The principal here is that in the case of unaligned IO on
both ends, beginning and end, we will send two read requests
one like old code, before the calculation of the first stripe,
and also a new site, before the calculation of the last stripe.
If any "boundary" is aligned or the complete IO is within a single
stripe. we do a single read like before.
The code is clean and simple by splitting the old _read_4_write
into 3 even parts:
1._read_4_write_first_stripe
2. _read_4_write_last_stripe
3. _read_4_write_execute
And calling 1+3 at the same place as before. 2+3 before last
stripe, and in the case of all in a single stripe then 1+2+3
is preformed additively.
Why did I not think of it before. Well I had a strike of
genius because I have stared at this code for 2 years, and did
not find this simple solution, til today. Not that I did not try.
This solution is much better for NFS than the previous supposedly
solution because the short write was dealt with out-of-band after
IO_done, which would cause for a seeky IO pattern where as in here
we execute in order. At both solutions we do 2 separate reads, only
here we do it within a single IO request. (And actually combine two
writes into a single submission)
NFS/exofs code need not change since the ORE API communicates the new
shorter length on return, what will happen is that this case would not
occur anymore.
hurray!!
[Stable this is an NFS bug since 3.2 Kernel should apply cleanly]
CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
If list_for_each_entry, etc complete a traversal of the list, the iterator
variable ends up pointing to an address at an offset from the list head,
and not a meaningful structure. Thus this value should not be used after
the end of the iterator. Replace a field access from orphan by NULL in two
places.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
identifier c;
expression E;
iterator name list_for_each_entry;
statement S;
@@
list_for_each_entry(c,...) { ... when != break;
when forall
when strict
}
...
(
c = E
|
*c
)
// </smpl>
Artem: fortunately, this did not cause any issues because we iterate the orphan
list using the elements count, so we never dereferenced the corrupted pointer.
This is why I do not send this patch to -stable. But otherwise - well spotted!
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
In the log reply code we assume that 'c->lhead_offs' is known and may be
non-zero, which is not the case because we do not store it in the master
node and have to find out by scanning on every mount. Knowing this fact
allows us to simplify the log scanning loop a bit and remove a couple
of unneeded local variables.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
This patch adds another debugfs knob which switches UBIFS to R/O mode.
I needed it while trying to reproduce the 'first log node is not CS node'
bug. Without this debugfs knob you have to perform a power cut to repruduce
the bug. The knob is named 'ro_error' and all it does is it sets the
'ro_error' UBIFS flag which makes UBIFS disallow any further writes - even
write-back will fail with -EROFS. Useful for debugging.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Fix the following compilation warning:
fs/ubifs/dir.c: In function 'ubifs_rename':
fs/ubifs/dir.c:972:15: warning: 'saved_nlink' may be used uninitialized
in this function
Use the 'uninitialized_var()' macro to get rid of this false-positive.
Artem: massaged the patch a bit.
Signed-off-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
UBIFS has a feature called "empty space fix-up" which is a quirk to work-around
limitations of dumb flasher programs. Namely, of those flashers that are unable
to skip NAND pages full of 0xFFs while flashing, resulting in empty space at
the end of half-filled eraseblocks to be unusable for UBIFS. This feature is
relatively new (introduced in v3.0).
The fix-up routine (fixup_free_space()) is executed only once at the very first
mount if the superblock has the 'space_fixup' flag set (can be done with -F
option of mkfs.ubifs). It basically reads all the UBIFS data and metadata and
writes it back to the same LEB. The routine assumes the image is pristine and
does not have anything in the journal.
There was a bug in 'fixup_free_space()' where it fixed up the log incorrectly.
All but one LEB of the log of a pristine file-system are empty. And one
contains just a commit start node. And 'fixup_free_space()' just unmapped this
LEB, which resulted in wiping the commit start node. As a result, some users
were unable to mount the file-system next time with the following symptom:
UBIFS error (pid 1): replay_log_leb: first log node at LEB 3:0 is not CS node
UBIFS error (pid 1): replay_log_leb: log error detected while replaying the log at LEB 3:0
The root-cause of this bug was that 'fixup_free_space()' wrongly assumed
that the beginning of empty space in the log head (c->lhead_offs) was known
on mount. However, it is not the case - it was always 0. UBIFS does not store
in it the master node and finds out by scanning the log on every mount.
The fix is simple - just pass commit start node size instead of 0 to
'fixup_leb()'.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Cc: stable@vger.kernel.org [v3.0+]
Reported-by: Iwo Mergler <Iwo.Mergler@netcommwireless.com>
Tested-by: Iwo Mergler <Iwo.Mergler@netcommwireless.com>
Reported-by: James Nute <newten82@gmail.com>
This patch reduces GFS2 file fragmentation by pre-reserving blocks. The
resulting improved on disk layout greatly speeds up operations in cases
which would have resulted in interlaced allocation of blocks previously.
A typical example of this is 10 parallel dd processes, each writing to a
file in a common dirctory.
The implementation uses an rbtree of reservations attached to each
resource group (and each inode).
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Pull CIFS fixes from Steve French.
* git://git.samba.org/sfrench/cifs-2.6:
cifs: always update the inode cache with the results from a FIND_*
cifs: when CONFIG_HIGHMEM is set, serialize the read/write kmaps
cifs: on CONFIG_HIGHMEM machines, limit the rsize/wsize to the kmap space
Initialise mid_q_entry before putting it on the pending queue
In the unlikely setup where there's only one resource group in the gfs2
filesystem, gfs2_rgrpd_get_next() returns a NULL rgd that is not dealt with
properly, causing a kernel NULL ptr dereference. This patch fixes this issue.
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Add missing flags that userspace derived from the protocol version number. This
makes the protocol more flexible.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
A fuse-based network filesystem might allow for the inode
and/or file data to change unexpectedly. A local client
that opens and repeatedly reads a file might never pick
up on such changes and indefinitely return stale data.
Always invoke fuse_update_attributes() in the read path
to cause an attr revalidation when the attributes expire.
This leads to a page cache invalidation if necessary and
ensures fuse issues new read requests to the fuse client.
The original logic (reval only on reads beyond EOF) is
preserved unless the client specifies FUSE_AUTO_INVAL_DATA
on init.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
We currently invalidate the inode address space mapping
if the file size changes unexpectedly. In the case of a
fuse network filesystem, a portion of a file could be
overwritten remotely without changing the file size.
Compare the old mtime as well to detect this condition
and invalidate the mapping if the file has been updated.
The original logic (to ignore changes in mtime) is
preserved unless the client specifies FUSE_AUTO_INVAL_DATA
on init.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Decoding the binary trace w/ a different kernel might be troublesome
since we convert addresses to symbols. For kernels with minimal changes,
the mappings would probably match, but it's not guaranteed at all.
(But still we could convert the addresses by hand, since we do print
raw addresses.)
If we use modules, the symbols could be loaded at different addresses
from the previously booted kernel, and so this would also fail, but
there's nothing we can do about it.
Also, the binary data format that pstore/ram is using in its ringbuffer
may change between the kernels, so here we too must ensure that we're
running the same kernel.
So, there are two questions really:
1. How to compute the unique kernel tag;
2. Where to store it.
In this patch we're using LINUX_VERSION_CODE, just as hibernation
(suspend-to-disk) does. This way we are protecting from the kernel
version mismatch, making sure that we're running the same kernel
version and patch level. We could use CRC of a symbol table (as
suggested by Tony Luck), but for now let's not be that strict.
And as for storing, we are using a small trick here. Instead of
allocating a dedicated buffer for the tag (i.e. another prz), or
hacking ram_core routines to "reserve" some control data in the
buffer, we are just encoding the tag into the buffer signature
(and XOR'ing it with the actual signature value, so that buffers
not needing a tag can just pass zero, which will result into the
plain old PRZ signature).
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Suggested-by: Tony Luck <tony.luck@intel.com>
Suggested-by: Colin Cross <ccross@android.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
