->permission() sanitizing: don't pass flags to ->inode_permission()

pass that via mask instead.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
selinux: don't transliterate MAY_NOT_BLOCK to IPERM_FLAG_RCU

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
security: optimize avc_audit() common path

avc_audit() did a lot of jumping around and had a big stack frame, all
for the uncommon case.

Split up the uncommon case (which we really can't make go fast anyway)
into its own slow function, and mark the conditional branches
appropriately for the common likely case.

This causes avc_audit() to no longer show up as one of the hottest
functions on the branch profiles (the new "perf -b" thing), and makes
the cycle profiles look really nice and dense too.

The whole audit path is still annoyingly very much one of the biggest
costs of name lookup, so these things are worth optimizing for.  I wish
we could just tell people to turn it off, but realistically we do need
it: we just need to make sure that the overhead of the necessary evil is
as low as possible.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
selinux: don't inline slow-path code into avc_has_perm_noaudit()

The selinux AVC paths remain some of the hottest (and deepest) codepaths
at filename lookup time, and we make it worse by having the slow path
cases take up I$ and stack space even when they don't trigger.  Gcc
tends to always want to inline functions that are just called once -
never mind that this might make for slower and worse code in the caller.

So this tries to improve on it a bit by making the slow-path cases
explicitly separate functions that are marked noinline, causing gcc to
at least no longer allocate stack space for them unless they are
actually called.  It also seems to help register allocation a tiny bit,
since gcc now doesn't take the slow case code into account.

Uninlining the slow path may also allow us to inline the remaining hot
path into the one caller that actually matters: avc_has_perm_flags().
I'll have to look at that separately, but both avc_audit() and
avc_has_perm_noaudit() are now small and lean enough that inlining them
may make sense.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
selinux: inline avc_audit() and avc_has_perm_noaudit() into caller

Now that all the slow-path code is gone from these functions, we can
inline them into the main caller - avc_has_perm_flags().

Now the compiler can see that 'avc' is allocated on the stack for this
case, which helps register pressure a bit.  It also actually shrinks the
total stack frame, because the stack frame that avc_has_perm_flags()
always needed (for that 'avc' allocation) is now sufficient for the
inlined functions too.

Inlining isn't bad - but mindless inlining of cold code (see the
previous commit) is.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Trifan <jimsth@gmail.com>
SELinux: remove avd from slow_avc_audit()

We don't use the argument, so remove it.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Trifan <jimsth@gmail.com>