This structure is now only 4 bytes, so its more efficient
to cache a copy rather than its address.
No significant size difference in allmodconfig vmlinux.
With non-modular kernel that has all XFRM options enabled, this
series reduces vmlinux image size by ~11kb. All xfrm_mode
indirections are gone and all modes are built-in.
before (ipsec-next master):
text data bss dec filename
21071494 7233140 11104324 39408958 vmlinux.master
after this series:
21066448 7226772 11104324 39397544 vmlinux.patched
With allmodconfig kernel, the size increase is only 362 bytes,
even all the xfrm config options removed in this series are
modular.
before:
text data bss dec filename
15731286 6936912 4046908 26715106 vmlinux.master
after this series:
15731492 6937068 4046908 26715468 vmlinux
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
after previous changes, xfrm_mode contains no function pointers anymore
and all modules defining such struct contain no code except an init/exit
functions to register the xfrm_mode struct with the xfrm core.
Just place the xfrm modes core and remove the modules,
the run-time xfrm_mode register/unregister functionality is removed.
Before:
text data bss dec filename
7523 200 2364 10087 net/xfrm/xfrm_input.o
40003 628 440 41071 net/xfrm/xfrm_state.o
15730338 6937080 4046908 26714326 vmlinux
7389 200 2364 9953 net/xfrm/xfrm_input.o
40574 656 440 41670 net/xfrm/xfrm_state.o
15730084 6937068 4046908 26714060 vmlinux
The xfrm*_mode_{transport,tunnel,beet} modules are gone.
v2: replace CONFIG_INET6_XFRM_MODE_* IS_ENABLED guards with CONFIG_IPV6
ones rather than removing them.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Adds an EXPORT_SYMBOL for afinfo_get_rcu, as it will now be called from
ipv6 in case of CONFIG_IPV6=m.
This change has virtually no effect on vmlinux size, but it reduces
afinfo size and allows followup patch to make xfrm modes const.
v2: mark if (afinfo) tests as likely (Sabrina)
re-fetch afinfo according to inner_mode in xfrm_prepare_input().
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
similar to previous patch: no external module dependencies,
so we can avoid the indirection by placing this in the core.
This change removes the last indirection from xfrm_mode and the
xfrm4|6_mode_{beet,tunnel}.c modules contain (almost) no code anymore.
Before:
text data bss dec hex filename
3957 136 0 4093 ffd net/xfrm/xfrm_output.o
587 44 0 631 277 net/ipv4/xfrm4_mode_beet.o
649 32 0 681 2a9 net/ipv4/xfrm4_mode_tunnel.o
625 44 0 669 29d net/ipv6/xfrm6_mode_beet.o
599 32 0 631 277 net/ipv6/xfrm6_mode_tunnel.o
After:
text data bss dec hex filename
5359 184 0 5543 15a7 net/xfrm/xfrm_output.o
171 24 0 195 c3 net/ipv4/xfrm4_mode_beet.o
171 24 0 195 c3 net/ipv4/xfrm4_mode_tunnel.o
172 24 0 196 c4 net/ipv6/xfrm6_mode_beet.o
172 24 0 196 c4 net/ipv6/xfrm6_mode_tunnel.o
v2: fold the *encap_add functions into xfrm*_prepare_output
preserve (move) output2 comment (Sabrina)
use x->outer_mode->encap, not inner
fix a build breakage on ppc (kbuild robot)
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Same is input indirection. Only exception: we need to export
xfrm_outer_mode_output for pktgen.
Increases size of vmlinux by about 163 byte:
Before:
text data bss dec filename
15730208 6936948 4046908 26714064 vmlinux
After:
15730311 6937008 4046908 26714227 vmlinux
xfrm_inner_extract_output has no more external callers, make it static.
v2: add IS_ENABLED(IPV6) guard in xfrm6_prepare_output
add two missing breaks in xfrm_outer_mode_output (Sabrina Dubroca)
add WARN_ON_ONCE for 'call AF_INET6 related output function, but
CONFIG_IPV6=n' case.
make xfrm_inner_extract_output static
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Lots of conflicts, by happily all cases of overlapping
changes, parallel adds, things of that nature.
Thanks to Stephen Rothwell, Saeed Mahameed, and others
for their guidance in these resolutions.
Signed-off-by: David S. Miller <davem@davemloft.net>
secpath_set is a wrapper for secpath_dup that will not perform
an allocation if the secpath attached to the skb has a reference count
of one, i.e., it doesn't need to be COW'ed.
Also, secpath_dup doesn't attach the secpath to the skb, it leaves
this to the caller.
Use secpath_set in places that immediately assign the return value to
skb.
This allows to remove skb->sp without touching these spots again.
secpath_dup can eventually be removed in followup patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
xfrm_output_one() does not return a error code when there is
no dst_entry attached to the skb, it is still possible crash
with a NULL pointer dereference in xfrm_output_resume(). Fix
it by return error code -EHOSTUNREACH.
Fixes: 9e14379378 ("xfrm: Fix NULL pointer dereference when skb_dst_force clears the dst_entry.")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Minor conflict in net/core/rtnetlink.c, David Ahern's bug fix in 'net'
overlapped the renaming of a netlink attribute in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
Steffen Klassert says:
====================
pull request (net): ipsec 2018-10-01
1) Validate address prefix lengths in the xfrm selector,
otherwise we may hit undefined behaviour in the
address matching functions if the prefix is too
big for the given address family.
2) Fix skb leak on local message size errors.
From Thadeu Lima de Souza Cascardo.
3) We currently reset the transport header back to the network
header after a transport mode transformation is applied. This
leads to an incorrect transport header when multiple transport
mode transformations are applied. Reset the transport header
only after all transformations are already applied to fix this.
From Sowmini Varadhan.
4) We only support one offloaded xfrm, so reset crypto_done after
the first transformation in xfrm_input(). Otherwise we may call
the wrong input method for subsequent transformations.
From Sowmini Varadhan.
5) Fix NULL pointer dereference when skb_dst_force clears the dst_entry.
skb_dst_force does not really force a dst refcount anymore, it might
clear it instead. xfrm code did not expect this, add a check to not
dereference skb_dst() if it was cleared by skb_dst_force.
6) Validate xfrm template mode, otherwise we can get a stack-out-of-bounds
read in xfrm_state_find. From Sean Tranchetti.
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 222d7dbd25 ("net: prevent dst uses after free")
skb_dst_force() might clear the dst_entry attached to the skb.
The xfrm code don't expect this to happen, so we crash with
a NULL pointer dereference in this case. Fix it by checking
skb_dst(skb) for NULL after skb_dst_force() and drop the packet
in cast the dst_entry was cleared.
Fixes: 222d7dbd25 ("net: prevent dst uses after free")
Reported-by: Tobias Hommel <netdev-list@genoetigt.de>
Reported-by: Kristian Evensen <kristian.evensen@gmail.com>
Reported-by: Wolfgang Walter <linux@stwm.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
An SKB is not on a list if skb->next is NULL.
Codify this convention into a helper function and use it
where we are dequeueing an SKB and need to mark it as such.
Signed-off-by: David S. Miller <davem@davemloft.net>
We already support setting an output mark at the xfrm_state,
unfortunately this does not support the input direction and
masking the marks that will be applied to the skb. This change
adds support applying a masked value in both directions.
The existing XFRMA_OUTPUT_MARK number is reused for this purpose
and as it is now bi-directional, it is renamed to XFRMA_SET_MARK.
An additional XFRMA_SET_MARK_MASK attribute is added for setting the
mask. If the attribute mask not provided, it is set to 0xffffffff,
keeping the XFRMA_OUTPUT_MARK existing 'full mask' semantics.
Co-developed-by: Tobias Brunner <tobias@strongswan.org>
Co-developed-by: Eyal Birger <eyal.birger@gmail.com>
Co-developed-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Tobias Brunner <tobias@strongswan.org>
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
In the xfrm_local_error, rcu_read_unlock should be called when afinfo
is not NULL. because xfrm_state_get_afinfo calls rcu_read_unlock
if afinfo is NULL.
Fixes: af5d27c4e1 ("xfrm: remove xfrm_state_put_afinfo")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Only IPSEC routes have a non-NULL dst->child pointer. And IPSEC
routes are identified by a non-NULL dst->xfrm pointer.
Signed-off-by: David S. Miller <davem@davemloft.net>
We reset the encapsulation field of the skb too early
in xfrm_output. As a result, the GRE GSO handler does
not segment the packets. This leads to a performance
drop down. We fix this by resetting the encapsulation
field right before we do the transformation, when
the inner headers become invalid.
Fixes: f1bd7d659e ("xfrm: Add encapsulation header offsets while SKB is not encrypted")
Reported-by: Vicente De Luca <vdeluca@zendesk.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
On systems that use mark-based routing it may be necessary for
routing lookups to use marks in order for packets to be routed
correctly. An example of such a system is Android, which uses
socket marks to route packets via different networks.
Currently, routing lookups in tunnel mode always use a mark of
zero, making routing incorrect on such systems.
This patch adds a new output_mark element to the xfrm state and
a corresponding XFRMA_OUTPUT_MARK netlink attribute. The output
mark differs from the existing xfrm mark in two ways:
1. The xfrm mark is used to match xfrm policies and states, while
the xfrm output mark is used to set the mark (and influence
the routing) of the packets emitted by those states.
2. The existing mark is constrained to be a subset of the bits of
the originating socket or transformed packet, but the output
mark is arbitrary and depends only on the state.
The use of a separate mark provides additional flexibility. For
example:
- A packet subject to two transforms (e.g., transport mode inside
tunnel mode) can have two different output marks applied to it,
one for the transport mode SA and one for the tunnel mode SA.
- On a system where socket marks determine routing, the packets
emitted by an IPsec tunnel can be routed based on a mark that
is determined by the tunnel, not by the marks of the
unencrypted packets.
- Support for setting the output marks can be introduced without
breaking any existing setups that employ both mark-based
routing and xfrm tunnel mode. Simply changing the code to use
the xfrm mark for routing output packets could xfrm mark could
change behaviour in a way that breaks these setups.
If the output mark is unspecified or set to zero, the mark is not
set or changed.
Tested: make allyesconfig; make -j64
Tested: https://android-review.googlesource.com/452776
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Both esp4 and esp6 used to assume that the SKB payload is encrypted
and therefore the inner_network and inner_transport offsets are
not relevant.
When doing crypto offload in the NIC, this is no longer the case
and the NIC driver needs these offsets so it can do TX TCP checksum
offloading.
This patch sets the inner_network and inner_transport members of
the SKB, as well as encapsulation, to reflect the actual positions
of these headers, and removes them only once encryption is done
on the payload.
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This patch adds all the bits that are needed to do
IPsec hardware offload for IPsec states and ESP packets.
We add xfrmdev_ops to the net_device. xfrmdev_ops has
function pointers that are needed to manage the xfrm
states in the hardware and to do a per packet
offloading decision.
Joint work with:
Ilan Tayari <ilant@mellanox.com>
Guy Shapiro <guysh@mellanox.com>
Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Guy Shapiro <guysh@mellanox.com>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
The inner headers are invalid after a xfrm transformation.
So reset the skb encapsulation field to ensure nobody tries
to access the inner headers.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Skb_gso_segment() uses skb control block during segmentation.
This patch adds 32-bytes room for previous control block which
will be copied into all resulting segments.
This patch fixes kernel crash during fragmenting forwarded packets.
Fragmentation requires valid IP CB in skb for clearing ip options.
Also patch removes custom save/restore in ovs code, now it's redundant.
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Link: http://lkml.kernel.org/r/CALYGNiP-0MZ-FExV2HutTvE9U-QQtkKSoE--KN=JQE5STYsjAA@mail.gmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
For consistency with the other similar methods in the kernel pass a
struct sock into the dst_ops .local_out method.
Simplifying the socket passing case is needed a prequel to passing a
struct net reference into .local_out.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace dst_output_okfn with dst_output
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In code review it was noticed that I had failed to add some blank lines
in places where they are customarily used. Taking a second look at the
code I have to agree blank lines would be nice so I have added them
here.
Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is immediately motivated by the bridge code that chains functions that
call into netfilter. Without passing net into the okfns the bridge code would
need to guess about the best expression for the network namespace to process
packets in.
As net is frequently one of the first things computed in continuation functions
after netfilter has done it's job passing in the desired network namespace is in
many cases a code simplification.
To support this change the function dst_output_okfn is introduced to
simplify passing dst_output as an okfn. For the moment dst_output_okfn
just silently drops the struct net.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass a network namespace parameter into the netfilter hooks. At the
call site of the netfilter hooks the path a packet is taking through
the network stack is well known which allows the network namespace to
be easily and reliabily.
This allows the replacement of magic code like
"dev_net(state->in?:state->out)" that appears at the start of most
netfilter hooks with "state->net".
In almost all cases the network namespace passed in is derived
from the first network device passed in, guaranteeing those
paths will not see any changes in practice.
The exceptions are:
xfrm/xfrm_output.c:xfrm_output_resume() xs_net(skb_dst(skb)->xfrm)
ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont() ip_vs_conn_net(cp)
ipvs/ip_vs_xmit.c:ip_vs_send_or_cont() ip_vs_conn_net(cp)
ipv4/raw.c:raw_send_hdrinc() sock_net(sk)
ipv6/ip6_output.c:ip6_xmit() sock_net(sk)
ipv6/ndisc.c:ndisc_send_skb() dev_net(skb->dev) not dev_net(dst->dev)
ipv6/raw.c:raw6_send_hdrinc() sock_net(sk)
br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev
In all cases these exceptions seem to be a better expression for the
network namespace the packet is being processed in then the historic
"dev_net(in?in:out)". I am documenting them in case something odd
pops up and someone starts trying to track down what happened.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a sock paramter to dst_output making dst_output_sk superfluous.
Add a skb->sk parameter to all of the callers of dst_output
Have the callers of dst_output_sk call dst_output.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As xfrm_output_one() is the only caller of skb_dst_pop(), we should
make skb_dst_pop() localized.
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On the output paths in particular, we have to sometimes deal with two
socket contexts. First, and usually skb->sk, is the local socket that
generated the frame.
And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.
We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.
The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device. We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_gso_segment has three possible return values:
1. a pointer to the first segmented skb
2. an errno value (IS_ERR())
3. NULL. This can happen when GSO is used for header verification.
However, several callers currently test IS_ERR instead of IS_ERR_OR_NULL
and would oops when NULL is returned.
Note that these call sites should never actually see such a NULL return
value; all callers mask out the GSO bits in the feature argument.
However, there have been issues with some protocol handlers erronously not
respecting the specified feature mask in some cases.
It is preferable to get 'have to turn off hw offloading, else slow' reports
rather than 'kernel crashes'.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
We need to choose the protocol family by skb->protocol. Otherwise we
call the wrong xfrm{4,6}_local_error handler in case an ipv6 sockets is
used in ipv4 mode, in which case we should call down to xfrm4_local_error
(ip6 sockets are a superset of ip4 ones).
We are called before before ip_output functions, so skb->protocol is
not reset.
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
In xfrm4 and xfrm6 we need to take care about sockets of the other
address family. This could happen because a 6in4 or 4in6 tunnel could
get protected by ipsec.
Because we don't want to have a run-time dependency on ipv6 when only
using ipv4 xfrm we have to embed a pointer to the correct local_error
function in xfrm_state_afinet and look it up when returning an error
depending on the socket address family.
Thanks to vi0ss for the great bug report:
<https://bugzilla.kernel.org/show_bug.cgi?id=58691>
v2:
a) fix two more unsafe interpretations of skb->sk as ipv6 socket
(xfrm6_local_dontfrag and __xfrm6_output)
v3:
a) add an EXPORT_SYMBOL_GPL(xfrm_local_error) to fix a link error when
building ipv6 as a module (thanks to Steffen Klassert)
Reported-by: <vi0oss@gmail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Clean up unnecessary assignment and jump. While there, fix up the label
name.
Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The error exit path needs err explicitly set. Otherwise it
returns success and the only caller, xfrm_output_resume(),
would oops in skb_dst(skb)->ops derefence as skb_dst(skb) is
NULL.
Bug introduced in commit bb65a9cb (xfrm: removes a superfluous
check and add a statistic).
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Cc: Li RongQing <roy.qing.li@gmail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the check if x->km.state equal to XFRM_STATE_VALID in
xfrm_state_check_expire(), which will be done before call
xfrm_state_check_expire().
add a LINUX_MIB_XFRMOUTSTATEINVALID statistic to record the
outbound error due to invalid xfrm state.
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
The xfrm_state argument is unused in this function, so remove it.
Also the name xfrm_state_check_space does not really match what this
function does. It actually checks if we have enough head and tailroom
on the skb. So we rename the function to xfrm_skb_check_space.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We clone the child entry in skb_dst_pop before we call
skb_dst_drop(). Otherwise we might kill the child right
before we return it to the caller.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Crypto requests might return asynchronous. In this case we leave
the rcu protected region, so force a refcount on the skb's
destination entry before we enter the xfrm type input/output
handlers.
This fixes a crash when a route is deleted whilst sending IPsec
data that is transformed by an asynchronous algorithm.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To support multiple versions of replay detection, we move the replay
detection functions to a separate file and make them accessible
via function pointers contained in the struct xfrm_replay.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
To support IPsec extended sequence numbers, we split the
output sequence numbers of xfrm_skb_cb in low and high order 32 bits
and we add the high order 32 bits to the input sequence numbers.
All users are updated accordingly.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
ip_local_out() is called with rcu_read_lock() held from ip_queue_xmit()
but not from other call sites.
Reported-and-bisected-by: Nick Bowler <nbowler@elliptictech.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
xfrm triggers a warning if dst_pop() drops a refcount
on a noref dst. This patch changes dst_pop() to
skb_dst_pop(). skb_dst_pop() drops the refcnt only
on a refcounted dst. Also we don't clone the child
dst_entry, so it is not refcounted and we can use
skb_dst_set_noref() in xfrm_output_one().
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Define three accessors to get/set dst attached to a skb
struct dst_entry *skb_dst(const struct sk_buff *skb)
void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)
void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;
Delete skb->dst field
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Westphal