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Several headers in the ice driver include ice.h even though they are
themselves included by that header. The most notable of these is
ice_common.h, but several other headers also do this.

Such a recursive inclusion is problematic as it forces headers to be
included in a strict order, otherwise compilation errors can result. The
circular inclusions do not trigger an endless loop due to standard
header inclusion guards, however other errors can occur.

For example, ice_flow.h defines ice_rss_hash_cfg, which is used by
ice_sriov.h as part of the definition of ice_vf_hash_ip_ctx.

ice_flow.h includes ice_acl.h, which includes ice_common.h, and which
finally includes ice.h. Since ice.h itself includes ice_sriov.h, this
creates a circular dependency.

The definition in ice_sriov.h requires things from ice_flow.h, but
ice_flow.h itself will lead to trying to load ice_sriov.h as part of its
process for expanding ice.h. The current code avoids this issue by
having an implicit dependency without the include of ice_flow.h.

If we were to fix that so that ice_sriov.h explicitly depends on
ice_flow.h the following pattern would occur:

  ice_flow.h -> ice_acl.h -> ice_common.h -> ice.h -> ice_sriov.h

At this point, during the expansion of, the header guard for ice_flow.h
is already set, so when ice_sriov.h attempts to load the ice_flow.h
header it is skipped. Then, we go on to begin including the rest of
ice_sriov.h, including structure definitions which depend on
ice_rss_hash_cfg. This produces a compiler warning because
ice_rss_hash_cfg hasn't yet been included. Remember, we're just at the
start of ice_flow.h!

If the order of headers is incorrect (ice_flow.h is not implicitly
loaded first in all files which include ice_sriov.h) then we get the
same failure.

Removing this recursive inclusion requires fixing a few cases where some
headers depended on the header inclusions from ice.h. In addition, a few
other changes are also required.

Most notably, ice_hw_to_dev is implemented as a macro in ice_osdep.h,
which is the likely reason that ice_common.h includes ice.h at all. This
macro implementation requires the full definition of ice_pf in order to
properly compile.

Fix this by moving it to a function declared in ice_main.c, so that we
do not require all files to depend on the layout of the ice_pf
structure.

Note that this change only fixes circular dependencies, but it does not
fully resolve all implicit dependencies where one header may depend on
the inclusion of another. I tried to fix as many of the implicit
dependencies as I noticed, but fixing them all requires a somewhat
tedious analysis of each header and attempting to compile it separately.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>