linux/include
Vladimir Oltean deab6b1cd9 net: dsa: tag_ocelot: break circular dependency with ocelot switch lib driver
As explained here:
https://lore.kernel.org/netdev/20210908220834.d7gmtnwrorhharna@skbuf/
DSA tagging protocol drivers cannot depend on symbols exported by switch
drivers, because this creates a circular dependency that breaks module
autoloading.

The tag_ocelot.c file depends on the ocelot_ptp_rew_op() function
exported by the common ocelot switch lib. This function looks at
OCELOT_SKB_CB(skb) and computes how to populate the REW_OP field of the
DSA tag, for PTP timestamping (the command: one-step/two-step, and the
TX timestamp identifier).

None of that requires deep insight into the driver, it is quite
stateless, as it only depends upon the skb->cb. So let's make it a
static inline function and put it in include/linux/dsa/ocelot.h, a
file that despite its name is used by the ocelot switch driver for
populating the injection header too - since commit 40d3f295b5 ("net:
mscc: ocelot: use common tag parsing code with DSA").

With that function declared as static inline, its body is expanded
inside each call site, so the dependency is broken and the DSA tagger
can be built without the switch library, upon which the felix driver
depends.

Fixes: 39e5308b32 ("net: mscc: ocelot: support PTP Sync one-step timestamping")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-12 17:35:18 -07:00
..
acpi Revert "ACPI: Add memory semantics to acpi_os_map_memory()" 2021-09-23 20:39:36 +02:00
asm-generic pci_iounmap'2: Electric Boogaloo: try to make sense of it all 2021-09-19 17:13:35 -07:00
clocksource
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-08-30 12:57:10 -07:00
drm drm/ttm: Include pagemap.h from ttm_tt.h 2021-08-16 14:44:05 +02:00
dt-bindings linux-watchdog 5.15-rc1 tag 2021-09-07 13:52:46 -07:00
keys
kunit
kvm KVM: arm64: Fix PMU probe ordering 2021-09-20 12:43:34 +01:00
linux net: dsa: tag_ocelot: break circular dependency with ocelot switch lib driver 2021-10-12 17:35:18 -07:00
math-emu
media
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2021-10-02 13:55:02 +01:00
pcmcia
ras
rdma Merge branch 'sg_nents' into rdma.git for-next 2021-08-30 09:49:59 -03:00
scsi scsi: core: Remove 'current_tag' 2021-09-22 00:13:38 -04:00
soc net: dsa: tag_ocelot: break circular dependency with ocelot switch lib driver 2021-10-12 17:35:18 -07:00
sound ALSA: rawmidi: introduce SNDRV_RAWMIDI_IOCTL_USER_PVERSION 2021-09-23 09:26:40 +02:00
target scsi: target: Allows backend drivers to fail with specific sense codes 2021-08-17 22:28:40 -04:00
trace cachefiles: Fix oops with cachefiles_cull() due to NULL object 2021-10-05 11:22:06 +01:00
uapi Networking fixes for 5.15-rc5, including fixes from xfrm, bpf, 2021-10-07 09:50:31 -07:00
vdso
video
xen swiotlb-xen: this is PV-only on x86 2021-09-20 17:01:21 +02:00