Its a valid use case to have null associated data in a ccm vector, but
this case isn't being handled properly right now.
The following ccm decryption/verification test vector, using the
rfc4309 implementation regularly triggers a panic, as will any
other vector with null assoc data:
* key: ab2f8a74b71cd2b1ff802e487d82f8b9
* iv: c6fb7d800d13abd8a6b2d8
* Associated Data: [NULL]
* Tag Length: 8
* input: d5e8939fc7892e2b
The resulting panic looks like so:
Unable to handle kernel paging request at ffff810064ddaec0 RIP:
[<ffffffff8864c4d7>] :ccm:get_data_to_compute+0x1a6/0x1d6
PGD 8063 PUD 0
Oops: 0002 [1] SMP
last sysfs file: /module/libata/version
CPU 0
Modules linked in: crypto_tester_kmod(U) seqiv krng ansi_cprng chainiv rng ctr aes_generic aes_x86_64 ccm cryptomgr testmgr_cipher testmgr aead crypto_blkcipher crypto_a
lgapi des ipv6 xfrm_nalgo crypto_api autofs4 hidp l2cap bluetooth nfs lockd fscache nfs_acl sunrpc ip_conntrack_netbios_ns ipt_REJECT xt_state ip_conntrack nfnetlink xt_
tcpudp iptable_filter ip_tables x_tables dm_mirror dm_log dm_multipath scsi_dh dm_mod video hwmon backlight sbs i2c_ec button battery asus_acpi acpi_memhotplug ac lp sg
snd_intel8x0 snd_ac97_codec ac97_bus snd_seq_dummy snd_seq_oss joydev snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss ide_cd snd_pcm floppy parport_p
c shpchp e752x_edac snd_timer e1000 i2c_i801 edac_mc snd soundcore snd_page_alloc i2c_core cdrom parport serio_raw pcspkr ata_piix libata sd_mod scsi_mod ext3 jbd uhci_h
cd ohci_hcd ehci_hcd
Pid: 12844, comm: crypto-tester Tainted: G 2.6.18-128.el5.fips1 #1
RIP: 0010:[<ffffffff8864c4d7>] [<ffffffff8864c4d7>] :ccm:get_data_to_compute+0x1a6/0x1d6
RSP: 0018:ffff8100134434e8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8100104898b0 RCX: ffffffffab6aea10
RDX: 0000000000000010 RSI: ffff8100104898c0 RDI: ffff810064ddaec0
RBP: 0000000000000000 R08: ffff8100104898b0 R09: 0000000000000000
R10: ffff8100103bac84 R11: ffff8100104898b0 R12: ffff810010489858
R13: ffff8100104898b0 R14: ffff8100103bac00 R15: 0000000000000000
FS: 00002ab881adfd30(0000) GS:ffffffff803ac000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff810064ddaec0 CR3: 0000000012a88000 CR4: 00000000000006e0
Process crypto-tester (pid: 12844, threadinfo ffff810013442000, task ffff81003d165860)
Stack: ffff8100103bac00 ffff8100104898e8 ffff8100134436f8 ffffffff00000000
0000000000000000 ffff8100104898b0 0000000000000000 ffff810010489858
0000000000000000 ffff8100103bac00 ffff8100134436f8 ffffffff8864c634
Call Trace:
[<ffffffff8864c634>] :ccm:crypto_ccm_auth+0x12d/0x140
[<ffffffff8864cf73>] :ccm:crypto_ccm_decrypt+0x161/0x23a
[<ffffffff88633643>] :crypto_tester_kmod:cavs_test_rfc4309_ccm+0x4a5/0x559
[...]
The above is from a RHEL5-based kernel, but upstream is susceptible too.
The fix is trivial: in crypto/ccm.c:crypto_ccm_auth(), pctx->ilen contains
whatever was in memory when pctx was allocated if assoclen is 0. The tested
fix is to simply add an else clause setting pctx->ilen to 0 for the
assoclen == 0 case, so that get_data_to_compute() doesn't try doing
things its not supposed to.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When we get left-over bits from a slow walk, it means that the
underlying cipher has gone troppo. However, as we're handling
that case we should ensure that the caller terminates the walk.
This patch does this by setting walk->nbytes to zero.
Reported-by: Roel Kluin <roel.kluin@gmail.com>
Reported-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As it is if an algorithm with a zero-length IV is used (e.g.,
NULL encryption) with authenc, authenc may generate an SG entry
of length zero, which will trigger a BUG check in the hash layer.
This patch fixes it by skipping the IV SG generation if the IV
size is zero.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now that clients no longer need to be notified of channel arrival
dma_async_client_register can simply increment the dmaengine_ref_count.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
async_tx and net_dma each have open-coded versions of issue_pending_all,
so provide a common routine in dmaengine.
The implementation needs to walk the global device list, so implement
rcu to allow dma_issue_pending_all to run lockless. Clients protect
themselves from channel removal events by holding a dmaengine reference.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Allowing multiple clients to each define their own channel allocation
scheme quickly leads to a pathological situation. For memory-to-memory
offload all clients can share a central allocator.
This simply moves the existing async_tx allocator to dmaengine with
minimal fixups:
* async_tx.c:get_chan_ref_by_cap --> dmaengine.c:nth_chan
* async_tx.c:async_tx_rebalance --> dmaengine.c:dma_channel_rebalance
* split out common code from async_tx.c:__async_tx_find_channel -->
dma_find_channel
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Simply, if a client wants any dmaengine channel then prevent all dmaengine
modules from being removed. Once the clients are done re-enable module
removal.
Why?, beyond reducing complication:
1/ Tracking reference counts per-transaction in an efficient manner, as
is currently done, requires a complicated scheme to avoid cache-line
bouncing effects.
2/ Per-transaction ref-counting gives the false impression that a
dma-driver can be gracefully removed ahead of its user (net, md, or
dma-slave)
3/ None of the in-tree dma-drivers talk to hot pluggable hardware, but
if such an engine were built one day we still would not need to notify
clients of remove events. The driver can simply return NULL to a
->prep() request, something that is much easier for a client to handle.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
async_tx.ko is a consumer of dma channels. A circular dependency arises
if modules in drivers/dma rely on common code in async_tx.ko. It
prevents either module from being unloaded.
Move dma_wait_for_async_tx and async_tx_run_dependencies to dmaeninge.o
where they should have been from the beginning.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The tables used by the various AES algorithms are currently
computed at run-time. This has created an init ordering problem
because some AES algorithms may be registered before the tables
have been initialised.
This patch gets around this whole thing by precomputing the tables.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The comment for the deflate test vectors says the winbits parameter is 11,
while the deflate module actually uses -11 (a negative window bits parameter
enables the raw deflate format instead of the zlib format).
Correct this, to avoid confusion about the format used.
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ROTATE -> rol32
XOR was always used with the same destination, use ^=
PLUS/PLUSONE use ++ or +=
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
While its a slightly insane to bypass the key1 == key2 ||
key2 == key3 check in triple-des, since it reduces it to the
same strength as des, some folks do need to do this from time
to time for backwards compatibility with des.
My own case is FIPS CAVS test vectors. Many triple-des test
vectors use a single key, replicated 3x. In order to get the
expected results, des3_ede_setkey() needs to only reject weak
keys if the CRYPTO_TFM_REQ_WEAK_KEY flag is set.
Also sets a more appropriate RES flag when a weak key is found.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes sha512 and sha384 to the new shash interface.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The message schedule W (u64[80]) is too big for the stack. In order
for this algorithm to be used with shash it is moved to a static
percpu area.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes michael_mic to the new shash interface.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes wp512, wp384 and wp256 to the new shash interface.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes tgr192, tgr160 and tgr128 to the new shash interface.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes sha256 and sha224 to the new shash interface.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes md5 to the new shash interface.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes md4 to the new shash interface.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes sha1 to the new shash interface.
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since most cryptographic hash algorithms have no keys, this patch
makes the setkey function optional for ahash and shash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When self-testing (de)compression algorithms, make sure the actual size of
the (de)compressed output data matches the expected output size.
Otherwise, in case the actual output size would be smaller than the expected
output size, the subsequent buffer compare test would still succeed, and no
error would be reported.
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Base versions handle constant folding just fine.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This warning:
crypto/testmgr.c: In function ‘test_comp’:
crypto/testmgr.c:829: warning: ‘ret’ may be used uninitialized in this function
triggers because GCC correctly notices that in the ctcount == 0 &&
dtcount != 0 input condition case this function can return an undefined
value, if the second loop fails.
Remove the shadowed 'ret' variable from the second loop that was probably
unintended.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The ANSI X9.31 PRNG docs aren't particularly clear on how to increment DT,
but empirical testing shows we're incrementing from the wrong end. A 10,000
iteration Monte Carlo RNG test currently winds up not getting the expected
result.
From http://csrc.nist.gov/groups/STM/cavp/documents/rng/RNGVS.pdf :
# CAVS 4.3
# ANSI931 MCT
[X9.31]
[AES 128-Key]
COUNT = 0
Key = 9f5b51200bf334b5d82be8c37255c848
DT = 6376bbe52902ba3b67c925fa701f11ac
V = 572c8e76872647977e74fbddc49501d1
R = 48e9bd0d06ee18fbe45790d5c3fc9b73
Currently, we get 0dd08496c4f7178bfa70a2161a79459a after 10000 loops.
Inverting the DT increment routine results in us obtaining the expected result
of 48e9bd0d06ee18fbe45790d5c3fc9b73. Verified on both x86_64 and ppc64.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
While working with some FIPS RNGVS test vectors yesterday, I discovered a
little bug in the way the ansi_cprng code works right now.
For example, the following test vector (complete with expected result)
from http://csrc.nist.gov/groups/STM/cavp/documents/rng/RNGVS.pdf ...
Key = f3b1666d13607242ed061cabb8d46202
DT = e6b3be782a23fa62d71d4afbb0e922fc
V = f0000000000000000000000000000000
R = 88dda456302423e5f69da57e7b95c73a
...when run through ansi_cprng, yields an incorrect R value
of e2afe0d794120103d6e86a2b503bdfaa.
If I load up ansi_cprng w/dbg=1 though, it was fairly obvious what was
going wrong:
----8<----
getting 16 random bytes for context ffff810033fb2b10
Calling _get_more_prng_bytes for context ffff810033fb2b10
Input DT: 00000000: e6 b3 be 78 2a 23 fa 62 d7 1d 4a fb b0 e9 22 fc
Input I: 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Input V: 00000000: f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
tmp stage 0: 00000000: e6 b3 be 78 2a 23 fa 62 d7 1d 4a fb b0 e9 22 fc
tmp stage 1: 00000000: f4 8e cb 25 94 3e 8c 31 d6 14 cd 8a 23 f1 3f 84
tmp stage 2: 00000000: 8c 53 6f 73 a4 1a af d4 20 89 68 f4 58 64 f8 be
Returning new block for context ffff810033fb2b10
Output DT: 00000000: e7 b3 be 78 2a 23 fa 62 d7 1d 4a fb b0 e9 22 fc
Output I: 00000000: 04 8e cb 25 94 3e 8c 31 d6 14 cd 8a 23 f1 3f 84
Output V: 00000000: 48 89 3b 71 bc e4 00 b6 5e 21 ba 37 8a 0a d5 70
New Random Data: 00000000: 88 dd a4 56 30 24 23 e5 f6 9d a5 7e 7b 95 c7 3a
Calling _get_more_prng_bytes for context ffff810033fb2b10
Input DT: 00000000: e7 b3 be 78 2a 23 fa 62 d7 1d 4a fb b0 e9 22 fc
Input I: 00000000: 04 8e cb 25 94 3e 8c 31 d6 14 cd 8a 23 f1 3f 84
Input V: 00000000: 48 89 3b 71 bc e4 00 b6 5e 21 ba 37 8a 0a d5 70
tmp stage 0: 00000000: e7 b3 be 78 2a 23 fa 62 d7 1d 4a fb b0 e9 22 fc
tmp stage 1: 00000000: 80 6b 3a 8c 23 ae 8f 53 be 71 4c 16 fc 13 b2 ea
tmp stage 2: 00000000: 2a 4d e1 2a 0b 58 8e e6 36 b8 9c 0a 26 22 b8 30
Returning new block for context ffff810033fb2b10
Output DT: 00000000: e8 b3 be 78 2a 23 fa 62 d7 1d 4a fb b0 e9 22 fc
Output I: 00000000: c8 e2 01 fd 9f 4a 8f e5 e0 50 f6 21 76 19 67 9a
Output V: 00000000: ba 98 e3 75 c0 1b 81 8d 03 d6 f8 e2 0c c6 54 4b
New Random Data: 00000000: e2 af e0 d7 94 12 01 03 d6 e8 6a 2b 50 3b df aa
returning 16 from get_prng_bytes in context ffff810033fb2b10
----8<----
The expected result is there, in the first "New Random Data", but we're
incorrectly making a second call to _get_more_prng_bytes, due to some checks
that are slightly off, which resulted in our original bytes never being
returned anywhere.
One approach to fixing this would be to alter some byte_count checks in
get_prng_bytes, but it would mean the last DEFAULT_BLK_SZ bytes would be
copied a byte at a time, rather than in a single memcpy, so a slightly more
involved, equally functional, and ultimately more efficient way of fixing this
was suggested to me by Neil, which I'm submitting here. All of the RNGVS ANSI
X9.31 AES128 VST test vectors I've passed through ansi_cprng are now returning
the expected results with this change.
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ARRAY_SIZE is more concise to use when the size of an array is divided by
the size of its type or the size of its first element.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@i@
@@
#include <linux/kernel.h>
@depends on i using "paren.iso"@
type T;
T[] E;
@@
- (sizeof(E)/sizeof(T))
+ ARRAY_SIZE(E)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch swaps the role of libcrc32c and crc32c. Previously
the implementation was in libcrc32c and crc32c was a wrapper.
Now the code is in crc32c and libcrc32c just calls the crypto
layer.
The reason for the change is to tap into the algorithm selection
capability of the crypto API so that optimised implementations
such as the one utilising Intel's CRC32C instruction can be
used where available.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a test for the requirement that all crc32c algorithms
shall store the partial result in the first four bytes of the descriptor
context.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch allows shash algorithms to be used through the old hash
interface. This is a transitional measure so we can convert the
underlying algorithms to shash before converting the users across.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes /proc/crypto call the type-specific show function
if one is present before calling the legacy show functions for
cipher/digest/compress. This allows us to reuse the type values
for those legacy types. In particular, hash and digest will share
one type value while shash is phased in as the default hash type.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
It is often useful to save the partial state of a hash function
so that it can be used as a base for two or more computations.
The most prominent example is HMAC where all hashes start from
a base determined by the key. Having an import/export interface
means that we only have to compute that base once rather than
for each message.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch allows shash algorithms to be used through the ahash
interface. This is required before we can convert digest algorithms
over to shash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The shash interface replaces the current synchronous hash interface.
It improves over hash in two ways. Firstly shash is reentrant,
meaning that the same tfm may be used by two threads simultaneously
as all hashing state is stored in a local descriptor.
The other enhancement is that shash no longer takes scatter list
entries. This is because shash is specifically designed for
synchronous algorithms and as such scatter lists are unnecessary.
All existing hash users will be converted to shash once the
algorithms have been completely converted.
There is also a new finup function that combines update with final.
This will be extended to ahash once the algorithm conversion is
done.
This is also the first time that an algorithm type has their own
registration function. Existing algorithm types will be converted
to this way in due course.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch reintroduces a completely revamped crypto_alloc_tfm.
The biggest change is that we now take two crypto_type objects
when allocating a tfm, a frontend and a backend. In fact this
simply formalises what we've been doing behind the API's back.
For example, as it stands crypto_alloc_ahash may use an
actual ahash algorithm or a crypto_hash algorithm. Putting
this in the API allows us to do this much more cleanly.
The existing types will be converted across gradually.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The type exit function needs to undo any allocations done by the type
init function. However, the type init function may differ depending
on the upper-level type of the transform (e.g., a crypto_blkcipher
instantiated as a crypto_ablkcipher).
So we need to move the exit function out of the lower-level
structure and into crypto_tfm itself.
As it stands this is a no-op since nobody uses exit functions at
all. However, all cases where a lower-level type is instantiated
as a different upper-level type (such as blkcipher as ablkcipher)
will be converted such that they allocate the underlying transform
and use that instead of casting (e.g., crypto_ablkcipher casted
into crypto_blkcipher). That will need to use a different exit
function depending on the upper-level type.
This patch also allows the type init/exit functions to call (or not)
cra_init/cra_exit instead of always calling them from the top level.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This is a patch that was sent to me by Jarod Wilson, marking off my
outstanding todo to allow the ansi cprng to set/reset the DT counter value in a
cprng instance. Currently crytpo_rng_reset accepts a seed byte array which is
interpreted by the ansi_cprng as a {V key} tuple. This patch extends that tuple
to now be {V key DT}, with DT an optional value during reset. This patch also
fixes a bug we noticed in which the offset of the key area of the seed is
started at DEFAULT_PRNG_KSZ rather than DEFAULT_BLK_SZ as it should be.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove the private implementation of 32-bit rotation and unaligned
access with byteswapping.
As a bonus, fixes sparse warnings:
crypto/camellia.c:602:2: warning: cast to restricted __be32
crypto/camellia.c:603:2: warning: cast to restricted __be32
crypto/camellia.c:604:2: warning: cast to restricted __be32
crypto/camellia.c:605:2: warning: cast to restricted __be32
crypto/camellia.c:710:2: warning: cast to restricted __be32
crypto/camellia.c:711:2: warning: cast to restricted __be32
crypto/camellia.c:712:2: warning: cast to restricted __be32
crypto/camellia.c:713:2: warning: cast to restricted __be32
crypto/camellia.c:714:2: warning: cast to restricted __be32
crypto/camellia.c:715:2: warning: cast to restricted __be32
crypto/camellia.c:716:2: warning: cast to restricted __be32
crypto/camellia.c:717:2: warning: cast to restricted __be32
[Thanks to Tomoyuki Okazaki for spotting the typo]
Tested-by: Carlo E. Prelz <fluido@fluido.as>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The FIPS specification requires that should self test for any supported
crypto algorithm fail during operation in fips mode, we need to prevent
the use of any crypto functionality until such time as the system can
be re-initialized. Seems like the best way to handle that would be
to panic the system if we were in fips mode and failed a self test.
This patch implements that functionality. I've built and run it
successfully.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If we have at least one algorithm built-in then it no longer makes
sense to have the testing framework, and hence cryptomgr to be a
module. It should be either on or off, i.e., built-in or disabled.
This just happens to stop a potential runaway modprobe loop that
seems to trigger on at least one distro.
With fixes from Evgeniy Polyakov.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Mapping the destination multiple times is a misuse of the dma-api.
Since the destination may be reused as a source, ensure that it is only
mapped once and that it is mapped bidirectionally. This appears to add
ugliness on the unmap side in that it always reads back the destination
address from the descriptor, but gcc can determine that dma_unmap is a
nop and not emit the code that calculates its arguments.
Cc: <stable@kernel.org>
Cc: Saeed Bishara <saeed@marvell.com>
Acked-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx:
fsldma: allow Freescale Elo DMA driver to be compiled as a module
fsldma: remove internal self-test from Freescale Elo DMA driver
drivers/dma/dmatest.c: switch a GFP_ATOMIC to GFP_KERNEL
dmatest: properly handle duplicate DMA channels
drivers/dma/ioat_dma.c: drop code after return
async_tx: make async_tx_run_dependencies() easier to read
