| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
After this change conntrack operations (lookup, creation, matching from
ruleset) only access one instead of two sk_buff cache lines.
This works for normal conntracks because those are allocated from a slab
that guarantees hw cacheline or 8byte alignment (whatever is larger)
so the 3 bits needed for ctinfo won't overlap with nf_conn addresses.
Template allocation now does manual address alignment (see previous change)
on arches that don't have sufficent kmalloc min alignment.
Some spots intentionally use skb->_nfct instead of skb_nfct() helpers,
this is to avoid undoing the skb_nfct() use when we remove untracked
conntrack object in the future.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
The next change will merge skb->nfct pointer and skb->nfctinfo
status bits into single skb->_nfct (unsigned long) area.
For this to work nf_conn addresses must always be aligned at least on
an 8 byte boundary since we will need the lower 3bits to store nfctinfo.
Conntrack templates are allocated via kmalloc.
kbuild test robot reported
BUILD_BUG_ON failed: NFCT_INFOMASK >= ARCH_KMALLOC_MINALIGN
on v1 of this patchset, so not all platforms meet this requirement.
Do manual alignment if needed, the alignment offset is stored in the
nf_conn entry protocol area. This works because templates are not
handed off to L4 protocol trackers.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Add a helper to assign a nf_conn entry and the ctinfo bits to an sk_buff.
This avoids changing code in followup patch that merges skb->nfct and
skb->nfctinfo into skb->_nfct.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Followup patch renames skb->nfct and changes its type so add a helper to
avoid intrusive rename change later.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Next patch makes direct skb->nfct access illegal, reduce noise
in next patch by using accessors we already have.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
We should also toss nf_bridge_info, if any -- packet is leaving via
ip_local_out, also, this skb isn't bridged -- it is a locally generated
copy. Also this avoids the need to touch this later when skb->nfct is
replaced with 'unsigned long _nfct' in followup patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
It is never accessed for reading and the only places that write to it
are the icmp(6) handlers, which also set skb->nfct (and skb->nfctinfo).
The conntrack core specifically checks for attached skb->nfct after
->error() invocation and returns early in this case.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
If something fails in nf_tables_table_enable(), it unregisters the
chains. But the rollback code is the same as nf_tables_table_disable()
almostly, except there is one counter check. Now create one wrapper
function to eliminate the duplicated codes.
Signed-off-by: Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
The return value of nf_tables_table_lookup() is valid pointer or one
pointer error. There are two cases:
1) IS_ERR(table) is true, it would return the error or reset the
table as NULL, it is unnecessary to perform the latter check
"table != NULL".
2) IS_ERR(obj) is false, the table is one valid pointer. It is also
unnecessary to perform that check.
The nf_tables_newset() and nf_tables_newobj() have same logic codes.
In summary, we could move the block of condition check "table != NULL"
in the else block to eliminate the original condition checks.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
After adding the following nft rule, then ping 224.0.0.1:
# nft add rule netdev t c pkttype host counter
The warning complain message will be printed out again and again:
WARNING: CPU: 0 PID: 10182 at net/netfilter/nft_meta.c:163 \
nft_meta_get_eval+0x3fe/0x460 [nft_meta]
[...]
Call Trace:
<IRQ>
dump_stack+0x85/0xc2
__warn+0xcb/0xf0
warn_slowpath_null+0x1d/0x20
nft_meta_get_eval+0x3fe/0x460 [nft_meta]
nft_do_chain+0xff/0x5e0 [nf_tables]
So we should deal with PACKET_LOOPBACK in netdev family too. For ipv4,
convert it to PACKET_BROADCAST/MULTICAST according to the destination
address's type; For ipv6, convert it to PACKET_MULTICAST directly.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Since there's no broadcast address in IPV6, so in ipv6 family, the
PACKET_LOOPBACK must be multicast packets, there's no need to check
it again.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
In matches and targets that define a kernel-only tail to their
xt_match and xt_target data structs, add a field .usersize that
specifies up to where data is to be shared with userspace.
Performed a search for comment "Used internally by the kernel" to find
relevant matches and targets. Manually inspected the structs to derive
a valid offsetof.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Convert compat to copying entries, matches and targets one by one,
using the xt_match_to_user and xt_target_to_user helper functions.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Convert ebtables to copying entries, matches and targets one by one.
The solution is analogous to that of generic xt_(match|target)_to_user
helpers, but is applied to different structs.
Convert existing helpers ebt_make_XXXname helpers that overwrite
fields of an already copy_to_user'd struct with ebt_XXX_to_user
helpers that copy all relevant fields of the struct from scratch.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Convert arptables to copying entries, matches and targets one by one,
using the xt_match_to_user and xt_target_to_user helper functions.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Convert ip6tables to copying entries, matches and targets one by one,
using the xt_match_to_user and xt_target_to_user helper functions.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Convert iptables to copying entries, matches and targets one by one,
using the xt_match_to_user and xt_target_to_user helper functions.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
xt_entry_target, xt_entry_match and their private data may contain
kernel data.
Introduce helper functions xt_match_to_user, xt_target_to_user and
xt_data_to_user that copy only the expected fields. These replace
existing logic that calls copy_to_user on entire structs, then
overwrites select fields.
Private data is defined in xt_match and xt_target. All matches and
targets that maintain kernel data store this at the tail of their
private structure. Extend xt_match and xt_target with .usersize to
limit how many bytes of data are copied. The remainder is cleared.
If compatsize is specified, usersize can only safely be used if all
fields up to usersize use platform-independent types. Otherwise, the
compat_to_user callback must be defined.
This patch does not yet enable the support logic.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
To make the code clearer, use rb_entry() instead of container_of() to
deal with rbtree.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
implement sctp_error to let nf_conntrack_in validate crc32c on the packet
transport header. Assign skb->ip_summed to CHECKSUM_UNNECESSARY and return
NF_ACCEPT in case of successful validation; otherwise, return -NF_ACCEPT to
let netfilter skip connection tracking, like other protocols do.
Besides preventing corrupted packets from matching conntrack entries, this
fixes functionality of REJECT target: it was not generating any ICMP upon
reception of SCTP packets, because it was computing RFC 1624 checksum on
the packet and systematically mismatching crc32c in the SCTP header.
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
nf_conntrack needs to compute crc32c when dealing with SCTP packets.
Moreover, NF_NAT_PROTO_SCTP (currently selecting LIBCRC32C) can be enabled
only if conntrack support for SCTP is enabled. Therefore, move enabling of
kernel support for crc32c so that it is selected when NF_CT_PROTO_SCTP=y.
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
Similar to xt_connbytes, user can match how many average bytes per packet
a connection has transferred so far.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
We missed to add descriptions about NFT_CT_LABELS, NFT_CT_PKTS and
NFT_CT_BYTES, now add it.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
udplite nat was copied from udp nat, they are virtually 100% identical.
Not really surprising given udplite is just udp with partial csum coverage.
old:
text data bss dec hex filename
11606 1457 210 13273 33d9 nf_nat.ko
330 0 2 332 14c nf_nat_proto_udp.o
276 0 2 278 116 nf_nat_proto_udplite.o
new:
text data bss dec hex filename
11598 1457 210 13265 33d1 nf_nat.ko
640 0 4 644 284 nf_nat_proto_udp.o
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
udplite was copied from udp, they are virtually 100% identical.
This adds udplite tracker to udp instead, removes udplite module,
and then makes the udplite tracker builtin.
udplite will then simply re-use udp timeout settings.
It makes little sense to add separate sysctls, nowadays we have
fine-grained timeout policy support via the CT target.
old:
text data bss dec hex filename
1633 672 0 2305 901 nf_conntrack_proto_udp.o
1756 672 0 2428 97c nf_conntrack_proto_udplite.o
69526 17937 268 87731 156b3 nf_conntrack.ko
new:
text data bss dec hex filename
2442 1184 0 3626 e2a nf_conntrack_proto_udp.o
68565 17721 268 86554 1521a nf_conntrack.ko
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
The previous implementation of set_settings was modifying
the value of speed and duplex, but with the new API, it's not
possible. The structure ethtool_link_ksettings is defined
as const.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The ethtool api {get|set}_settings is deprecated.
We move this driver to new api {get|set}_link_ksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
There is a function in mdio for the old ethtool api gset.
We add a new function mdio45_ethtool_ksettings_get for the
new ethtool api glinksettings.
Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Saeed Mahameed says:
====================
Mellanox mlx5 core and ODP updates 2017-01-01
The following eleven patches mainly come from Artemy Kovalyov
who expanded mlx5 on-demand-paging (ODP) support. In addition
there are three cleanup patches which don't change any functionality,
but are needed to align codebase prior accepting other patches.
Memory region (MR) in IB can be huge and ODP (on-demand paging)
technique allows to use unpinned memory, which can be consumed and
released on demand. This allows to applications do not pin down
the underlying physical pages of the address space, and save from them
need to track the validity of the mappings.
Rather, the HCA requests the latest translations from the OS when pages
are not present, and the OS invalidates translations which are no longer
valid due to either non-present pages or mapping changes.
In existing ODP implementation applications is needed to register
memory buffers for communication, though registered memory regions
need not have valid mappings at registration time.
This patch set performs the following steps to expand
current ODP implementation:
1. It refactors UMR to support large regions, by introducing generic
function to perform HCA translation table modifications. This
function supports both atomic and process contexts and is not limited
by number of modified entries.
This function allows to enable reallocated memory regions of
arbitrary size, so adding MR cache buckets to support up to 16GB MRs.
2. It changes page fault event format and refactor page faults logic
together with addition of atomic support.
3. It prepares mlx5 core code to support implicit registration with
simplified and relaxed semantics.
Implicit ODP semantics allows to applications provide special memory
key that represents their complete address space. Thus all IO accesses
referencing to this key (with proper access rights associated with the key)
wouldn't need not register any virtual address range.
Thanks,
Artemy, Ilya and Leon
v1->v2:
- Don't use 'inline' in .c files
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Add "type" field to mlx5_core MKEY struct.
Check whether page fault happens on MKEY corresponding to MR.
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Handle ODP atomic operations. When initiator of RDMA atomic
operation use ODP MR to provide source data handle pagefault properly.
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
* Update page fault event according to last specification.
* Separate code path for page fault EQ, completion EQ and async EQ.
* Move page fault handling work queue from mlx5_ib static variable
into mlx5_core page fault EQ.
* Allocate memory to store ODP event dynamically as the
events arrive, since in atomic context - use mempool.
* Make mlx5_ib page fault handler run in process context.
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Update PAGE_FAULT_RESUME command layout.
Three bit fields describing page fault: rdma, rdma_write, req_res gave 8
possible combinations, while only a few were legal. Now they
are interpreted as three-bit type field, where former legal
combinations turns into corresponding types and unused were added as new
types.
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
In this change we turn mlx5_ib_update_mtt() into generic
mlx5_ib_update_xlt() to perfrom HCA translation table modifiactions
supporting both atomic and process contexts and not limited by number
of modified entries.
Using this function we increase preallocated MRs up to 16GB.
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Make use of extended UMR translation offset.
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
* Update struct mlx5_wqe_umr_ctrl_seg.
* Currenlty UMR send_flags aim only certain use cases: enabled/disable
cached MR, modifying XLT for ODP. By making flags independent make UMR
more flexible allowing arbitrary manipulations.
* Since different UMR formats have different entry sizes UMR request
should receive exact size of translation table update instead of
number of entries. Rename field npages to xlt_size in struct mlx5_umr_wr
and update relevant code accordingly.
* Add support of length64 bit.
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
This patch adds the following items to IFC file.
1. MLX5_MKC_ACCESS_MODE_KSM enum value for creating KSM memory keys.
KSM access mode used when indirect MKey associated with fixed memory
size entries.
2. null_mkey field that is used to indicate non-present KLM/KSM
entries, where it causes the device to generate page fault event
when trying to access it.
3. struct mlx5_ifc_cmd_hca_cap_bits capability bits indicating
related value/field is supported:
* fixed_buffer_size - MLX5_MKC_ACCESS_MODE_KSM
* umr_extended_translation_offset - translation_offset_42_16
in UMR ctrl segment
* null_mkey - null_mkey in QUERY_SPECIAL_CONTEXTS
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Clean up the following common code (to post a list of work requests to the
send queue of the specified QP) at various places and add a helper function
'mlx5_ib_post_send_wait' to implement the same.
- Initialize 'mlx5_ib_umr_context' on stack
- Assign "mlx5_umr_wr:wr:wr_cqe to umr_context.cqe
- Acquire the semaphore
- call ib_post_send with a single ib_send_wr
- wait_for_completion()
- Check for umr_context.status
- Release the semaphore
Signed-off-by: Binoy Jayan <binoy.jayan@linaro.org>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The order of features exposed by private mlx5-abi.h
file is CQE zipping, packet pacing and multi-packet WQE.
The internal order implemented in mlx5_ib_query_device() is
multi-packet WQE, CQE zipping and packet pacing.
Such difference hurts code readability, so let's sync,
while mlx5-abi.h (exposed to userspace) is the primary
order.
This commit doesn't change any functionality.
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Fix offset for reserved fields.
Fixes: 7486216b3a0b ("{net,IB}/mlx5: mlx5_ifc updates")
Fixes: b4ff3a36d3e4 ("net/mlx5: Use offset based reserved field names in the IFC header file")
Fixes: 7d5e14237a55 ("net/mlx5: Update mlx5_ifc hardware features")
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Kalle Valo says:
====================
wireless-drivers-next patches for 4.11
The most notable change here is the inclusion of airtime fairness
scheduling to ath9k. It prevents slow clients from hogging all the
airtime and unfairly slowing down faster clients.
Otherwise smaller changes and cleanup.
Major changes:
ath9k
* cleanup eeprom endian handling
* add airtime fairness scheduling
ath10k
* fix issues for new QCA9377 firmware version
* support dev_coredump() for firmware crash dump
* enable channel 169 on 5 GHz band
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
For core revision 3.x Address-Aligned Beats is available in two registers.
The DT property snps,aal was created for AAL in the DMA bus register,
which is a read/write bit.
The DT property snps,axi_all was created for AXI_AAL in the AXI bus mode
register, which is a read only bit that reflects the value of AAL in the
DMA bus register.
Since the value of snps,axi_all is never used in the driver,
and since the property was created for a bit that is read only,
it should be safe to remove the property.
Acked-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Yuval Mintz says:
====================
qed*: Driver updates
The more interesting changes in this series include:
- Restructuring of the qede files - qede_main.c has grown big and this
series splits it into 3 parts [patches #2 and #3].
- Some significant changes in the API through which RSS indirection
table gets configured [#8].
- Support for ndo_set_vf_trust() [#9] which would regulate which VFs
are allowed to use promisc/multi-promisc mode.
It also contains various minor changes to qed/qede, as well as
non-functional changes [#1, #12] to complement other changes.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
|
Florian Westphal
Feng
Liping Zhang
Willem de Bruijn
Geliang Tang
Davide Caratti
Philippe Reynes
David S. Miller
Artemy Kovalyov
Binoy Jayan
Leon Romanovsky
Max Gurtovoy
Niklas Cassel