This patch inlines the functions scatterwalk_start, scatterwalk_map
and scatterwalk_done as they're all tiny and mostly used by the block
cipher walker.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Nothing bad will happen even if sg->length is zero, so there is
no point in keeping this BUG_ON in scatterwalk_start.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The offset advance in scatterwalk_pagedone not only is unnecessary,
but it was also buggy when it was needed by scatterwalk_copychunks.
As the latter has long ago been fixed to call scatterwalk_advance
directly, we can remove this unnecessary offset adjustment.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When there is more data to be processed, the current test in
scatterwalk_done may prevent us from calling pagedone even when
we should.
In particular, if we're on an SG entry spanning multiple pages
where the last page is not a full page, we will incorrectly skip
calling pagedone on the second last page.
This patch fixes this by adding a separate test for whether we've
reached the end of a page.
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The function ablkcipher_done_slow is pretty much identical to
scatterwalk_copychunks except that it doesn't actually copy as
the processing hasn't been completed yet.
This patch allows scatterwalk_copychunks to be used in this case
by specifying out == 2.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch removes the now unused scatterwalk_bytes_sglen. Anyone
using this out-of-tree should switch over to sg_nents_for_len.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On architectures where flush_dcache_page is not needed, we will
end up generating all the code up to the PageSlab call. This is
because PageSlab operates on a volatile pointer and thus cannot
be optimised away.
This patch works around this by checking whether flush_dcache_page
is needed before we call PageSlab which then allows PageSlab to be
compiled awy.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a check for in scatterwalk_map_and_copy to avoid
copying from the same address to the same address. This is going
to be used for IV copying in AEAD IV generators.
There is no provision for partial overlaps.
This patch also uses the new scatterwalk_ffwd instead of doing
it by hand in scatterwalk_map_and_copy.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the scatterwalk_ffwd helper which can create an
SG list that starts in the middle of an existing SG list. The
new list may either be part of the existing list or be a chain
that latches onto part of the existing list.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Modify crypto drivers to use the generic SG helper since
both of them are equivalent and the one from crypto is redundant.
See also:
468577abe3 reverted in
b2ab4a57b0
Signed-off-by: Cristian Stoica <cristian.stoica@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Crypto layer only passes nbytes to encrypt but in omap-aes driver we need to
know number of SG elements to pass to dmaengine slave API. We add function for
the same to scatterwalk library.
Signed-off-by: Joel Fernandes <joelf@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We are done with the scattergather entry when the walk offset goes
past sg->offset + sg->length, not when it crosses a page boundary.
There is a similarly queer test in the second half of
scatterwalk_pagedone() that probably needs some scrutiny.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
It's illegal to call flush_dcache_page on slab pages on a number
of architectures. So this patch avoids doing so if PageSlab is
true.
In future we can move the flush_dcache_page call to those page
cache users that actually need it.
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
It's better to return silently than crash and burn when someone feeds us
a zero length. In particular the null digest algorithm when used as part
of authenc will do that to us.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Unfortunately the generic chaining hasn't been ported to all architectures
yet, and notably not s390. So this patch restores the chainging that we've
been using previously which does work everywhere.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The scatterwalk infrastructure is used by algorithms so it needs to
move out of crypto for future users that may live in drivers/crypto
or asm/*/crypto.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch converts the crypto scatterwalk code to use the generic
scatterlist chaining rather the version specific to crypto.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When scatterwalk is built as a module digest.c was broken because it
requires the crypto_km_types structure which is in scatterwalk. This
patch removes the crypto_km_types structure by encoding the logic into
crypto_kmap_type directly.
In fact, this even saves a few bytes of code (not to mention the data
structure itself) on i386 which is about the only place where it's
needed.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the function scatterwalk_map_and_copy which reads or
writes a chunk of data from a scatterlist at a given offset. It will
be used by authenc which would read/write the authentication data at
the end of the cipher/plain text.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On platforms where flush_dcache_page is needed we're currently flushing
the next page right than the one we've just processed. This patch fixes
the off-by-one error.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In the scatterwalk_copychunks loop, We should be advancing by
len_this_page and not nbytes. The latter is the total length.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In the loop in scatterwalk_copychunks(), if walk->offset is zero,
then scatterwalk_pagedone rounds that up to the nearest page boundary:
walk->offset += PAGE_SIZE - 1;
walk->offset &= PAGE_MASK;
which is a no-op in this case, so we don't advance to the next element
of the scatterlist array:
if (walk->offset >= walk->sg->offset + walk->sg->length)
scatterwalk_start(walk, sg_next(walk->sg));
and we end up copying the same data twice.
It appears that other callers of scatterwalk_{page}done first advance
walk->offset, so I believe that's the correct thing to do here.
This caused a bug in NFS when run with krb5p security, which would
cause some writes to fail with permissions errors--for example, writes
of less than 8 bytes (the des blocksize) at the start of a file.
A git-bisect shows the bug was originally introduced by
5c64097aa0, first in 2.6.19-rc1.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch prepares the scatterwalk code for use by the new block cipher
type.
Firstly it halves the size of scatter_walk on 32-bit platforms. This
is important as we allocate at least two of these objects on the stack
for each block cipher operation.
It also exports the symbols since the block cipher code can be built as
a module.
Finally there is a hack in scatterwalk_unmap that relies on progress
being made. Unfortunately, for hardware crypto we can't guarantee
progress to be made since the hardware can fail.
So this also gets rid of the hack by not advancing the address returned
by scatterwalk_map.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
A bunch of asm/bug.h includes are both not needed (since it will get
pulled anyway) and bogus (since they are done too early). Removed.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The VIA Padlock device is able to perform much better when multiple
blocks are fed to it at once. As this device offers an exceptional
throughput rate it is worthwhile to optimise the infrastructure
specifically for it.
We shift the existing page-sized fast path down to the CBC/ECB functions.
We can then replace the CBC/ECB functions with functions provided by the
underlying algorithm that performs the multi-block operations.
As a side-effect this improves the performance of large cipher operations
for all existing algorithm implementations. I've measured the gain to be
around 5% for 3DES and 15% for AES.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
