[XEN PATCH] x86/guest_walk: address violations of MISRA C:2012 Rule 8.3

[Federico Serafini <federico.serafini@xxxxxxxxxxx>]

Uniform declaration and definition of guest_walk_tables() using
parameter name "pfec_walk":
this name highlights the connection with PFEC_* constants and it is
consistent with the use of the parameter within function body.
No functional change.

Signed-off-by: Federico Serafini <federico.serafini@xxxxxxxxxxx>
---
 xen/arch/x86/include/asm/guest_pt.h |  2 +-
 xen/arch/x86/mm/guest_walk.c        | 39 +++++++++++++++--------------
 2 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/xen/arch/x86/include/asm/guest_pt.h 
b/xen/arch/x86/include/asm/guest_pt.h
index bc312343cd..5edf687dce 100644
--- a/xen/arch/x86/include/asm/guest_pt.h
+++ b/xen/arch/x86/include/asm/guest_pt.h
@@ -422,7 +422,7 @@ static inline unsigned int guest_walk_to_page_order(const 
walk_t *gw)
 
 bool
 guest_walk_tables(const struct vcpu *v, struct p2m_domain *p2m,
-                  unsigned long va, walk_t *gw, uint32_t pfec,
+                  unsigned long va, walk_t *gw, uint32_t pfec_walk,
                   gfn_t top_gfn, mfn_t top_mfn, void *top_map);
 
 /* Pretty-print the contents of a guest-walk */
diff --git a/xen/arch/x86/mm/guest_walk.c b/xen/arch/x86/mm/guest_walk.c
index fe7393334f..20a19bd7e2 100644
--- a/xen/arch/x86/mm/guest_walk.c
+++ b/xen/arch/x86/mm/guest_walk.c
@@ -69,7 +69,7 @@ static bool set_ad_bits(guest_intpte_t *guest_p, 
guest_intpte_t *walk_p,
  */
 bool
 guest_walk_tables(const struct vcpu *v, struct p2m_domain *p2m,
-                  unsigned long va, walk_t *gw, uint32_t walk,
+                  unsigned long va, walk_t *gw, uint32_t pfec_walk,
                   gfn_t top_gfn, mfn_t top_mfn, void *top_map)
 {
     struct domain *d = v->domain;
@@ -100,16 +100,17 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
      * inputs to a guest walk, but a whole load of code currently passes in
      * other PFEC_ constants.
      */
-    walk &= (PFEC_implicit | PFEC_insn_fetch | PFEC_user_mode | 
PFEC_write_access);
+    pfec_walk &= (PFEC_implicit | PFEC_insn_fetch | PFEC_user_mode |
+                  PFEC_write_access);
 
     /* Only implicit supervisor data accesses exist. */
-    ASSERT(!(walk & PFEC_implicit) ||
-           !(walk & (PFEC_insn_fetch | PFEC_user_mode)));
+    ASSERT(!(pfec_walk & PFEC_implicit) ||
+           !(pfec_walk & (PFEC_insn_fetch | PFEC_user_mode)));
 
     perfc_incr(guest_walk);
     memset(gw, 0, sizeof(*gw));
     gw->va = va;
-    gw->pfec = walk & (PFEC_user_mode | PFEC_write_access);
+    gw->pfec = pfec_walk & (PFEC_user_mode | PFEC_write_access);
 
     /*
      * PFEC_insn_fetch is only reported if NX or SMEP are enabled.  Hardware
@@ -117,7 +118,7 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
      * rights.
      */
     if ( guest_nx_enabled(v) || guest_smep_enabled(v) )
-        gw->pfec |= (walk & PFEC_insn_fetch);
+        gw->pfec |= (pfec_walk & PFEC_insn_fetch);
 
 #if GUEST_PAGING_LEVELS >= 3 /* PAE or 64... */
 #if GUEST_PAGING_LEVELS >= 4 /* 64-bit only... */
@@ -399,7 +400,7 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
      * N.B. In the case that the walk ended with a superpage, the fabricated
      * gw->l1e contains the appropriate leaf pkey.
      */
-    if ( !(walk & PFEC_insn_fetch) &&
+    if ( !(pfec_walk & PFEC_insn_fetch) &&
          ((ar & _PAGE_USER) ? guest_pku_enabled(v)
                             : guest_pks_enabled(v)) )
     {
@@ -408,8 +409,8 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
         unsigned int pk_ar = (pkr >> (pkey * PKEY_WIDTH)) & (PKEY_AD | 
PKEY_WD);
 
         if ( (pk_ar & PKEY_AD) ||
-             ((walk & PFEC_write_access) && (pk_ar & PKEY_WD) &&
-              ((walk & PFEC_user_mode) || guest_wp_enabled(v))) )
+             ((pfec_walk & PFEC_write_access) && (pk_ar & PKEY_WD) &&
+              ((pfec_walk & PFEC_user_mode) || guest_wp_enabled(v))) )
         {
             gw->pfec |= PFEC_prot_key;
             goto out;
@@ -417,17 +418,17 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
     }
 #endif
 
-    if ( (walk & PFEC_insn_fetch) && (ar & _PAGE_NX_BIT) )
+    if ( (pfec_walk & PFEC_insn_fetch) && (ar & _PAGE_NX_BIT) )
         /* Requested an instruction fetch and found NX? Fail. */
         goto out;
 
-    if ( walk & PFEC_user_mode ) /* Requested a user acess. */
+    if ( pfec_walk & PFEC_user_mode ) /* Requested a user acess. */
     {
         if ( !(ar & _PAGE_USER) )
             /* Got a supervisor walk?  Unconditional fail. */
             goto out;
 
-        if ( (walk & PFEC_write_access) && !(ar & _PAGE_RW) )
+        if ( (pfec_walk & PFEC_write_access) && !(ar & _PAGE_RW) )
             /* Requested a write and only got a read? Fail. */
             goto out;
     }
@@ -435,18 +436,18 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
     {
         if ( ar & _PAGE_USER ) /* Got a user walk. */
         {
-            if ( (walk & PFEC_insn_fetch) && guest_smep_enabled(v) )
+            if ( (pfec_walk & PFEC_insn_fetch) && guest_smep_enabled(v) )
                 /* User insn fetch and smep? Fail. */
                 goto out;
 
-            if ( !(walk & PFEC_insn_fetch) && guest_smap_enabled(v) &&
-                 ((walk & PFEC_implicit) ||
+            if ( !(pfec_walk & PFEC_insn_fetch) && guest_smap_enabled(v) &&
+                 ((pfec_walk & PFEC_implicit) ||
                   !(guest_cpu_user_regs()->eflags & X86_EFLAGS_AC)) )
                 /* User data access and smap? Fail. */
                 goto out;
         }
 
-        if ( (walk & PFEC_write_access) && !(ar & _PAGE_RW) &&
+        if ( (pfec_walk & PFEC_write_access) && !(ar & _PAGE_RW) &&
              guest_wp_enabled(v) )
             /* Requested a write, got a read, and CR0.WP is set? Fail. */
             goto out;
@@ -468,7 +469,7 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
 
     case 1:
         if ( set_ad_bits(&l1p[guest_l1_table_offset(va)].l1, &gw->l1e.l1,
-                         (walk & PFEC_write_access)) )
+                         (pfec_walk & PFEC_write_access)) )
         {
             paging_mark_dirty(d, gw->l1mfn);
             hvmemul_write_cache(v, l1gpa, &gw->l1e, sizeof(gw->l1e));
@@ -476,7 +477,7 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
         /* Fallthrough */
     case 2:
         if ( set_ad_bits(&l2p[guest_l2_table_offset(va)].l2, &gw->l2e.l2,
-                         (walk & PFEC_write_access) && leaf_level == 2) )
+                         (pfec_walk & PFEC_write_access) && leaf_level == 2) )
         {
             paging_mark_dirty(d, gw->l2mfn);
             hvmemul_write_cache(v, l2gpa, &gw->l2e, sizeof(gw->l2e));
@@ -485,7 +486,7 @@ guest_walk_tables(const struct vcpu *v, struct p2m_domain 
*p2m,
 #if GUEST_PAGING_LEVELS == 4 /* 64-bit only... */
     case 3:
         if ( set_ad_bits(&l3p[guest_l3_table_offset(va)].l3, &gw->l3e.l3,
-                         (walk & PFEC_write_access) && leaf_level == 3) )
+                         (pfec_walk & PFEC_write_access) && leaf_level == 3) )
         {
             paging_mark_dirty(d, gw->l3mfn);
             hvmemul_write_cache(v, l3gpa, &gw->l3e, sizeof(gw->l3e));
-- 
2.34.1