[PATCH bpf-next 0/2] lighten uapi/bpf.h rebuilds

Last change in the bpf headers - disentangling BPF uapi from
netdevice.h. Both linux/bpf.h and uapi/bpf.h changes should
now rebuild ~1k objects down from the original ~18k. There's
probably more that can be done but it's diminishing returns.

Split into two patches for ease of review.

Jakub Kicinski (2):
  net: add includes masked by netdevice.h including uapi/bpf.h
  bpf: invert the dependency between bpf-netns.h and netns/bpf.h

 drivers/net/ethernet/amazon/ena/ena_netdev.h       | 1 +
 drivers/net/ethernet/cavium/thunder/nicvf_queues.c | 1 +
 drivers/net/ethernet/microsoft/mana/mana_en.c      | 2 ++
 drivers/net/ethernet/stmicro/stmmac/stmmac.h       | 1 +
 drivers/net/ethernet/ti/cpsw_priv.h                | 2 ++
 include/linux/bpf-netns.h                          | 8 +-------
 include/net/netns/bpf.h                            | 9 ++++++++-
 kernel/bpf/net_namespace.c                         | 1 +
 8 files changed, 17 insertions(+), 8 deletions(-)

-- 
2.31.1

Add missing includes unmasked by the subsequent change.

Mostly network drivers missing an include for XDP_PACKET_HEADROOM.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
CC: shayagr@amazon.com
CC: akiyano@amazon.com
CC: darinzon@amazon.com
CC: ndagan@amazon.com
CC: saeedb@amazon.com
CC: sgoutham@marvell.com
CC: kys@microsoft.com
CC: haiyangz@microsoft.com
CC: sthemmin@microsoft.com
CC: wei.liu@kernel.org
CC: decui@microsoft.com
CC: peppe.cavallaro@st.com
CC: alexandre.torgue@foss.st.com
CC: joabreu@synopsys.com
CC: mcoquelin.stm32@gmail.com
CC: grygorii.strashko@ti.com
CC: sameehj@amazon.com
CC: chenhao288@hisilicon.com
CC: moyufeng@huawei.com
CC: linux-arm-kernel@lists.infradead.org
CC: linux-hyperv@vger.kernel.org
CC: linux-stm32@st-md-mailman.stormreply.com
CC: linux-omap@vger.kernel.org
---
 drivers/net/ethernet/amazon/ena/ena_netdev.h       | 1 +
 drivers/net/ethernet/cavium/thunder/nicvf_queues.c | 1 +
 drivers/net/ethernet/microsoft/mana/mana_en.c      | 2 ++
 drivers/net/ethernet/stmicro/stmmac/stmmac.h       | 1 +
 drivers/net/ethernet/ti/cpsw_priv.h                | 2 ++
 kernel/bpf/net_namespace.c                         | 1 +
 6 files changed, 8 insertions(+)

diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h
index 0c39fc2fa345..9391c7101fba 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.h
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h

@@ -14,6 +14,7 @@
 #include <linux/interrupt.h>
 #include <linux/netdevice.h>
 #include <linux/skbuff.h>
+#include <uapi/linux/bpf.h>
 
 #include "ena_com.h"
 #include "ena_eth_com.h"

diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
index 50bbe79fb93d..4367edbdd579 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c

@@ -10,6 +10,7 @@
 #include <linux/iommu.h>
 #include <net/ip.h>
 #include <net/tso.h>
+#include <uapi/linux/bpf.h>
 
 #include "nic_reg.h"
 #include "nic.h"

diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index c1d5a374b967..2ece9e90dc50 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c

@@ -1,6 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
 /* Copyright (c) 2021, Microsoft Corporation. */
 
+#include <uapi/linux/bpf.h>
+
 #include <linux/inetdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/ethtool.h>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index 4f5292cadf54..d42b6af32d6e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h

@@ -22,6 +22,7 @@
 #include <linux/net_tstamp.h>
 #include <linux/reset.h>
 #include <net/page_pool.h>
+#include <uapi/linux/bpf.h>
 
 struct stmmac_resources {
 	void __iomem *addr;

diff --git a/drivers/net/ethernet/ti/cpsw_priv.h b/drivers/net/ethernet/ti/cpsw_priv.h
index f33c882eb70e..74555970730c 100644
--- a/drivers/net/ethernet/ti/cpsw_priv.h
+++ b/drivers/net/ethernet/ti/cpsw_priv.h

@@ -6,6 +6,8 @@
 #ifndef DRIVERS_NET_ETHERNET_TI_CPSW_PRIV_H_
 #define DRIVERS_NET_ETHERNET_TI_CPSW_PRIV_H_
 
+#include <uapi/linux/bpf.h>
+
 #include "davinci_cpdma.h"
 
 #define CPSW_DEBUG	(NETIF_MSG_HW		| NETIF_MSG_WOL		| \

diff --git a/kernel/bpf/net_namespace.c b/kernel/bpf/net_namespace.c
index 542f275bf252..868cc2c43899 100644
--- a/kernel/bpf/net_namespace.c
+++ b/kernel/bpf/net_namespace.c

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
 #include <linux/bpf.h>
+#include <linux/bpf-netns.h>
 #include <linux/filter.h>
 #include <net/net_namespace.h>
 

-- 
2.31.1

netns/bpf.h gets included by netdevice.h (thru net_namespace.h)
which in turn gets included in a lot of places. We should keep
netns/bpf.h as light-weight as possible.

bpf-netns.h seems to contain more implementation details than
deserves to be included in a netns header. It needs to pull in
uapi/bpf.h to get various enum types.

Move enum netns_bpf_attach_type to netns/bpf.h and invert the
dependency. This makes netns/bpf.h fit the mold of a struct
definition header more clearly, and drops the number of objects
rebuilt when uapi/bpf.h is touched from 7.7k to 1.1k.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 include/linux/bpf-netns.h | 8 +-------
 include/net/netns/bpf.h   | 9 ++++++++-
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/include/linux/bpf-netns.h b/include/linux/bpf-netns.h
index 722f799c1a2e..413cfa5e4b07 100644
--- a/include/linux/bpf-netns.h
+++ b/include/linux/bpf-netns.h

@@ -3,15 +3,9 @@
 #define _BPF_NETNS_H
 
 #include <linux/mutex.h>
+#include <net/netns/bpf.h>
 #include <uapi/linux/bpf.h>
 
-enum netns_bpf_attach_type {
-	NETNS_BPF_INVALID = -1,
-	NETNS_BPF_FLOW_DISSECTOR = 0,
-	NETNS_BPF_SK_LOOKUP,
-	MAX_NETNS_BPF_ATTACH_TYPE
-};
-
 static inline enum netns_bpf_attach_type
 to_netns_bpf_attach_type(enum bpf_attach_type attach_type)
 {

diff --git a/include/net/netns/bpf.h b/include/net/netns/bpf.h
index 0ca6a1b87185..2c01a278d1eb 100644
--- a/include/net/netns/bpf.h
+++ b/include/net/netns/bpf.h

@@ -6,11 +6,18 @@
 #ifndef __NETNS_BPF_H__
 #define __NETNS_BPF_H__
 
-#include <linux/bpf-netns.h>
+#include <linux/list.h>
 
 struct bpf_prog;
 struct bpf_prog_array;
 
+enum netns_bpf_attach_type {
+	NETNS_BPF_INVALID = -1,
+	NETNS_BPF_FLOW_DISSECTOR = 0,
+	NETNS_BPF_SK_LOOKUP,
+	MAX_NETNS_BPF_ATTACH_TYPE
+};
+
 struct netns_bpf {
 	/* Array of programs to run compiled from progs or links */
 	struct bpf_prog_array __rcu *run_array[MAX_NETNS_BPF_ATTACH_TYPE];

-- 
2.31.1

Hi Jakub,

I love your patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]

url:    https://github.com/0day-ci/linux/commits/Jakub-Kicinski/lighten-uapi-bpf-h-rebuilds/20211230-063309
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: arm-randconfig-r025-20211230 (https://download.01.org/0day-ci/archive/20211230/202112300831.1tdh6vYJ-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project cd284b7ac0615afc6e0f1a30da2777e361de27a3)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        # https://github.com/0day-ci/linux/commit/df4183ffb29b84cb3cfb6ac82457f151e6fa2a28
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Jakub-Kicinski/lighten-uapi-bpf-h-rebuilds/20211230-063309
        git checkout df4183ffb29b84cb3cfb6ac82457f151e6fa2a28
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash net/ipv6/netfilter/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All error/warnings (new ones prefixed by >>):

   In file included from net/ipv6/netfilter/nf_reject_ipv6.c:8:
   In file included from include/net/ip6_route.h:24:

quoted

include/net/ip6_fib.h:548:2: error: type name requires a specifier or qualifier

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^

quoted

include/net/ip6_fib.h:548:22: warning: declaration of 'struct bpf_iter_meta' will not be visible outside of this function [-Wvisibility]

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                               ^

quoted

include/net/ip6_fib.h:548:39: warning: declaration specifier missing, defaulting to 'int'

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                                                ^
                                                int
   include/net/ip6_fib.h:549:2: error: type name requires a specifier or qualifier
           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:549:35: warning: declaration specifier missing, defaulting to 'int'
           __bpf_md_ptr(struct fib6_info *, rt);
                                            ^
                                            int

quoted

include/net/ip6_fib.h:549:2: error: duplicate member '__bpf_md_ptr'

           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:548:2: note: previous declaration is here
           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^
   net/ipv6/netfilter/nf_reject_ipv6.c:287:18: warning: variable 'ip6h' set but not used [-Wunused-but-set-variable]
           struct ipv6hdr *ip6h;
                           ^
   4 warnings and 3 errors generated.
--
   In file included from net/ipv6/netfilter/nf_dup_ipv6.c:13:
   In file included from include/net/ip6_route.h:24:

quoted

include/net/ip6_fib.h:548:2: error: type name requires a specifier or qualifier

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^

quoted

include/net/ip6_fib.h:548:22: warning: declaration of 'struct bpf_iter_meta' will not be visible outside of this function [-Wvisibility]

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                               ^

quoted

include/net/ip6_fib.h:548:39: warning: declaration specifier missing, defaulting to 'int'

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                                                ^
                                                int
   include/net/ip6_fib.h:549:2: error: type name requires a specifier or qualifier
           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:549:35: warning: declaration specifier missing, defaulting to 'int'
           __bpf_md_ptr(struct fib6_info *, rt);
                                            ^
                                            int

quoted

include/net/ip6_fib.h:549:2: error: duplicate member '__bpf_md_ptr'

           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:548:2: note: previous declaration is here
           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^
   3 warnings and 3 errors generated.


vim +548 include/net/ip6_fib.h

180ca444b985c4 Wei Wang      2017-10-06  537  
8d1c802b2815ed David Ahern   2018-04-17  538  void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
8d1c802b2815ed David Ahern   2018-04-17  539  static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
d4ead6b34b67fd David Ahern   2018-04-17  540  {
d4ead6b34b67fd David Ahern   2018-04-17  541  	return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
d4ead6b34b67fd David Ahern   2018-04-17  542  }
907eea486888cf Amit Cohen    2021-02-01  543  void fib6_info_hw_flags_set(struct net *net, struct fib6_info *f6i,
0c5fcf9e249ee1 Amit Cohen    2021-02-07  544  			    bool offload, bool trap, bool offload_failed);
180ca444b985c4 Wei Wang      2017-10-06  545  
3c32cc1bceba8a Yonghong Song 2020-05-13  546  #if IS_BUILTIN(CONFIG_IPV6) && defined(CONFIG_BPF_SYSCALL)
3c32cc1bceba8a Yonghong Song 2020-05-13  547  struct bpf_iter__ipv6_route {
3c32cc1bceba8a Yonghong Song 2020-05-13 @548  	__bpf_md_ptr(struct bpf_iter_meta *, meta);
3c32cc1bceba8a Yonghong Song 2020-05-13 @549  	__bpf_md_ptr(struct fib6_info *, rt);
3c32cc1bceba8a Yonghong Song 2020-05-13  550  };
3c32cc1bceba8a Yonghong Song 2020-05-13  551  #endif
3c32cc1bceba8a Yonghong Song 2020-05-13  552  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

Hi Jakub,

I love your patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]

url:    https://github.com/0day-ci/linux/commits/Jakub-Kicinski/lighten-uapi-bpf-h-rebuilds/20211230-063309
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: x86_64-randconfig-a002-20211230 (https://download.01.org/0day-ci/archive/20211230/202112300828.wqqaIPJ3-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project cd284b7ac0615afc6e0f1a30da2777e361de27a3)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/df4183ffb29b84cb3cfb6ac82457f151e6fa2a28
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Jakub-Kicinski/lighten-uapi-bpf-h-rebuilds/20211230-063309
        git checkout df4183ffb29b84cb3cfb6ac82457f151e6fa2a28
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash net/ipv6/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All error/warnings (new ones prefixed by >>):

   In file included from net/ipv6/anycast.c:39:
   In file included from include/net/ip6_route.h:24:

quoted

include/net/ip6_fib.h:548:2: error: type name requires a specifier or qualifier

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^

quoted

include/net/ip6_fib.h:548:22: warning: declaration of 'struct bpf_iter_meta' will not be visible outside of this function [-Wvisibility]

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                               ^

quoted

include/net/ip6_fib.h:548:39: warning: declaration specifier missing, defaulting to 'int'

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                                                ^
                                                int
   include/net/ip6_fib.h:549:2: error: type name requires a specifier or qualifier
           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:549:35: warning: declaration specifier missing, defaulting to 'int'
           __bpf_md_ptr(struct fib6_info *, rt);
                                            ^
                                            int

quoted

include/net/ip6_fib.h:549:2: error: duplicate member '__bpf_md_ptr'

           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:548:2: note: previous declaration is here
           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^
   3 warnings and 3 errors generated.
--
   In file included from net/ipv6/route.c:48:

quoted

include/net/ip6_fib.h:548:2: error: type name requires a specifier or qualifier

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^

quoted

include/net/ip6_fib.h:548:22: warning: declaration of 'struct bpf_iter_meta' will not be visible outside of this function [-Wvisibility]

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                               ^

quoted

include/net/ip6_fib.h:548:39: warning: declaration specifier missing, defaulting to 'int'

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                                                ^
                                                int
   include/net/ip6_fib.h:549:2: error: type name requires a specifier or qualifier
           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:549:35: warning: declaration specifier missing, defaulting to 'int'
           __bpf_md_ptr(struct fib6_info *, rt);
                                            ^
                                            int

quoted

include/net/ip6_fib.h:549:2: error: duplicate member '__bpf_md_ptr'

           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:548:2: note: previous declaration is here
           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^

quoted

net/ipv6/route.c:6612:5: error: no member named 'rt' in 'bpf_iter__ipv6_route'

                   { offsetof(struct bpf_iter__ipv6_route, rt),
                     ^                                     ~~
   include/linux/stddef.h:17:32: note: expanded from macro 'offsetof'
   #define offsetof(TYPE, MEMBER)  __compiler_offsetof(TYPE, MEMBER)
                                   ^                         ~~~~~~
   include/linux/compiler_types.h:140:35: note: expanded from macro '__compiler_offsetof'
   #define __compiler_offsetof(a, b)       __builtin_offsetof(a, b)
                                           ^                     ~
   3 warnings and 4 errors generated.
--
   In file included from net/ipv6/netfilter/nf_reject_ipv6.c:8:
   In file included from include/net/ip6_route.h:24:

quoted

include/net/ip6_fib.h:548:2: error: type name requires a specifier or qualifier

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^

quoted

include/net/ip6_fib.h:548:22: warning: declaration of 'struct bpf_iter_meta' will not be visible outside of this function [-Wvisibility]

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                               ^

quoted

include/net/ip6_fib.h:548:39: warning: declaration specifier missing, defaulting to 'int'

           __bpf_md_ptr(struct bpf_iter_meta *, meta);
                                                ^
                                                int
   include/net/ip6_fib.h:549:2: error: type name requires a specifier or qualifier
           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:549:35: warning: declaration specifier missing, defaulting to 'int'
           __bpf_md_ptr(struct fib6_info *, rt);
                                            ^
                                            int

quoted

include/net/ip6_fib.h:549:2: error: duplicate member '__bpf_md_ptr'

           __bpf_md_ptr(struct fib6_info *, rt);
           ^
   include/net/ip6_fib.h:548:2: note: previous declaration is here
           __bpf_md_ptr(struct bpf_iter_meta *, meta);
           ^
   net/ipv6/netfilter/nf_reject_ipv6.c:287:18: warning: variable 'ip6h' set but not used [-Wunused-but-set-variable]
           struct ipv6hdr *ip6h;
                           ^
   4 warnings and 3 errors generated.


vim +548 include/net/ip6_fib.h

180ca444b985c4 Wei Wang      2017-10-06  537  
8d1c802b2815ed David Ahern   2018-04-17  538  void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
8d1c802b2815ed David Ahern   2018-04-17  539  static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
d4ead6b34b67fd David Ahern   2018-04-17  540  {
d4ead6b34b67fd David Ahern   2018-04-17  541  	return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
d4ead6b34b67fd David Ahern   2018-04-17  542  }
907eea486888cf Amit Cohen    2021-02-01  543  void fib6_info_hw_flags_set(struct net *net, struct fib6_info *f6i,
0c5fcf9e249ee1 Amit Cohen    2021-02-07  544  			    bool offload, bool trap, bool offload_failed);
180ca444b985c4 Wei Wang      2017-10-06  545  
3c32cc1bceba8a Yonghong Song 2020-05-13  546  #if IS_BUILTIN(CONFIG_IPV6) && defined(CONFIG_BPF_SYSCALL)
3c32cc1bceba8a Yonghong Song 2020-05-13  547  struct bpf_iter__ipv6_route {
3c32cc1bceba8a Yonghong Song 2020-05-13 @548  	__bpf_md_ptr(struct bpf_iter_meta *, meta);
3c32cc1bceba8a Yonghong Song 2020-05-13 @549  	__bpf_md_ptr(struct fib6_info *, rt);
3c32cc1bceba8a Yonghong Song 2020-05-13  550  };
3c32cc1bceba8a Yonghong Song 2020-05-13  551  #endif
3c32cc1bceba8a Yonghong Song 2020-05-13  552  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org