[PATCH 07/11] x86/ucode/amd: Alter API for microcode_fits()

[Andrew Cooper <andrew.cooper3@citrix.com>]

Although it is logically a step in the wrong direction overall, it simplifies
the rearranging of cpu_request_microcode() substantially for microcode_fits()
to take struct microcode_header_amd directly, and not require an intermediate
struct microcode_amd pointing at it.

Make this change (taking time to rename 'mc_amd' to its eventual 'patch' to
reduce the churn in the series), and a later cleanup will make it uniformly
take a struct microcode_patch.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Wei Liu <wl@xen.org>
CC: Roger Pau Monné <roger.pau@citrix.com>
---
 xen/arch/x86/cpu/microcode/amd.c | 22 +++++++++-------------
 1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/xen/arch/x86/cpu/microcode/amd.c b/xen/arch/x86/cpu/microcode/amd.c
index 8318664f85..254f3dd4d7 100644
--- a/xen/arch/x86/cpu/microcode/amd.c
+++ b/xen/arch/x86/cpu/microcode/amd.c
@@ -173,31 +173,30 @@ static bool check_final_patch_levels(const struct cpu_signature *sig)
 }
 
 static enum microcode_match_result microcode_fits(
-    const struct microcode_amd *mc_amd)
+    const struct microcode_header_amd *patch)
 {
     unsigned int cpu = smp_processor_id();
     const struct cpu_signature *sig = &per_cpu(cpu_sig, cpu);
-    const struct microcode_header_amd *mc_header = mc_amd->mpb;
 
     if ( equiv.sig != sig->sig ||
-         equiv.id  != mc_header->processor_rev_id )
+         equiv.id  != patch->processor_rev_id )
         return MIS_UCODE;
 
-    if ( mc_header->patch_id <= sig->rev )
+    if ( patch->patch_id <= sig->rev )
     {
         pr_debug("microcode: patch is already at required level or greater.\n");
         return OLD_UCODE;
     }
 
     pr_debug("microcode: CPU%d found a matching microcode update with version %#x (current=%#x)\n",
-             cpu, mc_header->patch_id, sig->rev);
+             cpu, patch->patch_id, sig->rev);
 
     return NEW_UCODE;
 }
 
 static bool match_cpu(const struct microcode_patch *patch)
 {
-    return patch && (microcode_fits(patch) == NEW_UCODE);
+    return patch && (microcode_fits(patch->mpb) == NEW_UCODE);
 }
 
 static void free_patch(struct microcode_patch *mc_amd)
@@ -223,14 +222,11 @@ static enum microcode_match_result compare_header(
 static enum microcode_match_result compare_patch(
     const struct microcode_patch *new, const struct microcode_patch *old)
 {
-    const struct microcode_header_amd *new_header = new->mpb;
-    const struct microcode_header_amd *old_header = old->mpb;
-
     /* Both patches to compare are supposed to be applicable to local CPU. */
-    ASSERT(microcode_fits(new) != MIS_UCODE);
-    ASSERT(microcode_fits(old) != MIS_UCODE);
+    ASSERT(microcode_fits(new->mpb) != MIS_UCODE);
+    ASSERT(microcode_fits(old->mpb) != MIS_UCODE);
 
-    return compare_header(new_header, old_header);
+    return compare_header(new->mpb, old->mpb);
 }
 
 static int apply_microcode(const struct microcode_patch *patch)
@@ -509,7 +505,7 @@ static struct microcode_patch *cpu_request_microcode(const void *buf,
          * If the new ucode covers current CPU, compare ucodes and store the
          * one with higher revision.
          */
-        if ( (microcode_fits(mc_amd) != MIS_UCODE) &&
+        if ( (microcode_fits(mc_amd->mpb) != MIS_UCODE) &&
              (!saved || (compare_header(mc_amd->mpb, saved) == NEW_UCODE)) )
         {
             xfree(saved);
-- 
2.11.0