Move convert_context inside dm_crypt_io.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Fix possible max_phys_segments violation in cloned dm-crypt bio.

In write operation dm-crypt needs to allocate new bio request
and run crypto operation on this clone. Cloned request has always
the same size, but number of physical segments can be increased
and violate max_phys_segments restriction.

This can lead to data corruption and serious hardware malfunction.
This was observed when using XFS over dm-crypt and at least
two HBA controller drivers (arcmsr, cciss) recently.

Fix it by using bio_add_page() call (which tests for other
restrictions too) instead of constructing own biovec.

All versions of dm-crypt are affected by this bug.

Cc: stable@kernel.org
Cc:  dm-crypt@saout.de
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Fix BIO_UPTODATE test for write io.

Cc: stable@kernel.org
Cc: dm-crypt@saout.de
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

This patch fixes the errors made in the users of the crypto layer during
the sg_init_table conversion.  It also adds a few conversions that were
missing altogether.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Most drivers need to set length and offset as well, so may as well fold
those three lines into one.

Add sg_assign_page() for those two locations that only needed to set
the page, where the offset/length is set outside of the function context.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Add crypt prefix to dec_pending to avoid confusing it in backtraces with
the dm core function of the same name.

No functional change here.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Replace numbers with names in labels in error paths, to avoid confusion
when new one get added between existing ones.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Clean up, convert some spaces to tabs.

No functional change here.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Add post-processing queue (per crypt device) for read operations.

Current implementation uses only one queue for all operations
and this can lead to starvation caused by many requests waiting
for memory allocation. But the needed memory-releasing operation
is queued after these requests (in the same queue).
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Use a separate single-threaded workqueue for each crypt device
instead of one global workqueue.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Insert missing kfree() in crypt_iv_essiv_ctr() error path.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Add a missing 'dm_put_device' in an error path in crypt target constructor.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".
Signed-off-by: NRobert P. J. Day <rpjday@mindspring.com>
Signed-off-by: NAdrian Bunk <bunk@kernel.org>

dm-crypt used the ->bi_size member in the bio endio handling to
free the appropriate pages, but it frees all of it from both call
paths. With the ->bi_end_io() changes, ->bi_size was always 0 since
we don't do partial completes. This caused dm-crypt to leak memory.

Fix this by removing the size argument from crypt_free_buffer_pages().
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

As bi_end_io is only called once when the reqeust is complete,
the 'size' argument is now redundant.  Remove it.

Now there is no need for bio_endio to subtract the size completed
from bi_size.  So don't do that either.

While we are at it, change bi_end_io to return void.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Flush workqueue before releasing bioset and mopools in dm-crypt.  There can
be finished but not yet released request.

Call chain causing oops:
  run workqueue
    dec_pending
      bio_endio(...);
      	<remove device request - remove mempool>
      mempool_free(io, cc->io_pool);

This usually happens when cryptsetup create temporary
luks mapping in the beggining of crypt device activation.

When dm-core calls destructor crypt_dtr, no new request
are possible.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Christophe Saout <christophe@saout.de>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch causes device-mapper to reject any barrier requests.  This is done
since most of the targets won't handle this correctly anyway.  So until the
situation improves it is better to reject these requests at the first place.
Since barrier requests won't get to the targets, the checks there can be
removed.

Cc: stable@kernel.org
Signed-off-by: NStefan Bader <shbader@de.ibm.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use new KMEM_CACHE() macro and make the newly-exposed structure names more
meaningful.  Also remove some superfluous casts and inlines (let a modern
compiler be the judge).
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a new IV generation method 'null' to read old filesystem images created
with SuSE's loop_fish2 module.
Signed-off-by: NLudwig Nussel <ludwig.nussel@suse.de>
Acked-By: NChristophe Saout <christophe@saout.de>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allocate smaller clones

With the previous dm-crypt fixes, there is no need for the clone bios to have
the same bvec size as the original - we just need to make them big enough for
the remaining number of pages.  The only requirement is that we clear the
"out" index in convert_context, so that crypt_convert starts storing data at
the right position within the clone bio.
Signed-off-by: NOlaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Get rid of first_clone in dm-crypt

This gets rid of first_clone, which is not really needed.  Apparently, cloned
bios used to share their bvec some time way in the past - this is no longer
the case.  Contrarily, this even hurts us if we try to create a clone off
first_clone after it has completed, and crypt_endio has destroyed its bvec.
Signed-off-by: NOlaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Do not access the bio after generic_make_request

We should never access a bio after generic_make_request - there's no guarantee
it still exists.
Signed-off-by: NOlaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Call clone_init early

We need to call clone_init as early as possible - at least before call
bio_put(clone) in any error path.  Otherwise, the destructor will try to
dereference bi_private, which may still be NULL.
Signed-off-by: NOlaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Disable barriers in dm-crypt because of current workqueue processing can
reorder requests.

This must be addresed later but for now disabling barriers is needed to
prevent data corruption.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently we scale the mempool sizes depending on memory installed
in the machine, except for the bio pool itself which sits at a fixed
256 entry pre-allocation.

There's really no point in "optimizing" this OOM path, we just need
enough preallocated to make progress. A single unit is enough, lets
scale it down to 2 just to be on the safe side.

This patch saves ~150kb of pinned kernel memory on a 32-bit box.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Update existing targets to use the new symbols for return values from target
map and end_io functions.

There is no effect on behaviour.

Test results:
Done build test without errors.
Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This facility provides three entry points:

	ilog2()		Log base 2 of unsigned long
	ilog2_u32()	Log base 2 of u32
	ilog2_u64()	Log base 2 of u64

These facilities can either be used inside functions on dynamic data:

	int do_something(long q)
	{
		...;
		y = ilog2(x)
		...;
	}

Or can be used to statically initialise global variables with constant values:

	unsigned n = ilog2(27);

When performing static initialisation, the compiler will report "error:
initializer element is not constant" if asked to take a log of zero or of
something not reducible to a constant.  They treat negative numbers as
unsigned.

When not dealing with a constant, they fall back to using fls() which permits
them to use arch-specific log calculation instructions - such as BSR on
x86/x86_64 or SCAN on FRV - if available.

[akpm@osdl.org: MMC fix]
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Wojtek Kaniewski <wojtekka@toxygen.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Rather than stuffing integers into pointers with casts, let's use
a union.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes the IV u64-aligned since essiv does a u64 store to it.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

LRW-32-AES needs a certain IV. This IV should be provided dm-crypt.
The block cipher mode could, in principle generate the correct IV from
the plain IV, but I think that it is cleaner to supply the right IV
directly.

The sector -> narrow block calculation uses a shift for performance reasons.
This shift is computed in .ctr and stored in cc->iv_gen_private (as a void *).
Signed-off-by: NRik Snel <rsnel@cube.dyndns.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Fix up for make allyesconfig.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>

Fix dm-crypt after the block cipher API changes to correctly return the
backwards compatible cipher-chainmode[-ivmode] format for "dmsetup
table".
Signed-off-by: NChristophe Saout <christophe@saout.de>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

diff linux-2.6.19-rc3.orig/drivers/md/dm-crypt.c linux-2.6.19-rc3/drivers/md/dm-crypt.c

Separate out the concept of "queue congestion" from "backing-dev congestion".
Congestion is a backing-dev concept, not a queue concept.

The blk_* congestion functions are retained, as wrappers around the core
backing-dev congestion functions.

This proper layering is needed so that NFS can cleanly use the congestion
functions, and so that CONFIG_BLOCK=n actually links.

Cc: "Thomas Maier" <balagi@justmail.de>
Cc: "Jens Axboe" <jens.axboe@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: David Howells <dhowells@redhat.com>
Cc: Peter Osterlund <petero2@telia.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

In the low memory situation dm-crypt needs to use a private mempool of bios to
avoid blocking.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch is designed to help dm-crypt comply with the
new constraints imposed by the following patch in -mm:
  md-dm-reduce-stack-usage-with-stacked-block-devices.patch

Under low memory the existing implementation relies upon waiting for I/O
submitted recursively to generic_make_request() completing before the original
generic_make_request() call can return.

This patch moves the I/O submission to a workqueue so the original
generic_make_request() can return immediately.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Restructure the dm-crypt write processing in preparation for workqueue changes
in the next patches.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Restructure part of the dm-crypt code in preparation for workqueue changes.

Use 'base_bio' or 'clone' variable names consistently throughout.  No
functional changes are included in this patch.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add the facility to wipe the encryption key from memory (for example while a
laptop is suspended) and reinstate it later (when the laptop gets resumed).
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>