From: Jan Beulich <jbeulich@suse.com>
Date: Wed, 4 Nov 2020 08:27:22 +0000 (+0100)
Subject: x86/mm: drop guest_get_eff_l1e()
X-Git-Tag: archive/raspbian/4.16.0+51-g0941d6cb-1+rpi1~2^2~42^2~1433
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=9ff9705647646aa937b5f5c1426a64c69a62b3bd;p=xen.git

x86/mm: drop guest_get_eff_l1e()

There's no actual user of it: pv_ro_page_fault() has a
guest_kernel_mode() conditional around its only call site.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
---

diff --git a/xen/arch/x86/pv/mm.c b/xen/arch/x86/pv/mm.c
index 14cb0f2d4e..5d74d11cba 100644
--- a/xen/arch/x86/pv/mm.c
+++ b/xen/arch/x86/pv/mm.c
@@ -55,27 +55,6 @@ l1_pgentry_t *map_guest_l1e(unsigned long linear, mfn_t *gl1mfn)
     return (l1_pgentry_t *)map_domain_page(*gl1mfn) + l1_table_offset(linear);
 }
 
-/*
- * Read the guest's l1e that maps this address, from the kernel-mode
- * page tables.
- */
-static l1_pgentry_t guest_get_eff_kern_l1e(unsigned long linear)
-{
-    struct vcpu *curr = current;
-    const bool user_mode = !(curr->arch.flags & TF_kernel_mode);
-    l1_pgentry_t l1e;
-
-    if ( user_mode )
-        toggle_guest_pt(curr);
-
-    l1e = guest_get_eff_l1e(linear);
-
-    if ( user_mode )
-        toggle_guest_pt(curr);
-
-    return l1e;
-}
-
 /*
  * Map a guest's LDT page (covering the byte at @offset from start of the LDT)
  * into Xen's virtual range.  Returns true if the mapping changed, false
diff --git a/xen/arch/x86/pv/mm.h b/xen/arch/x86/pv/mm.h
index b1b66e46c8..2a21859dd4 100644
--- a/xen/arch/x86/pv/mm.h
+++ b/xen/arch/x86/pv/mm.h
@@ -5,8 +5,11 @@ l1_pgentry_t *map_guest_l1e(unsigned long linear, mfn_t *gl1mfn);
 
 int new_guest_cr3(mfn_t mfn);
 
-/* Read a PV guest's l1e that maps this linear address. */
-static inline l1_pgentry_t guest_get_eff_l1e(unsigned long linear)
+/*
+ * Read the guest's l1e that maps this address, from the kernel-mode
+ * page tables.
+ */
+static inline l1_pgentry_t guest_get_eff_kern_l1e(unsigned long linear)
 {
     l1_pgentry_t l1e;
 
diff --git a/xen/arch/x86/pv/ro-page-fault.c b/xen/arch/x86/pv/ro-page-fault.c
index 7f6fbc92fb..8d0007ede5 100644
--- a/xen/arch/x86/pv/ro-page-fault.c
+++ b/xen/arch/x86/pv/ro-page-fault.c
@@ -342,7 +342,7 @@ int pv_ro_page_fault(unsigned long addr, struct cpu_user_regs *regs)
     bool mmio_ro;
 
     /* Attempt to read the PTE that maps the VA being accessed. */
-    pte = guest_get_eff_l1e(addr);
+    pte = guest_get_eff_kern_l1e(addr);
 
     /* We are only looking for read-only mappings */
     if ( ((l1e_get_flags(pte) & (_PAGE_PRESENT | _PAGE_RW)) != _PAGE_PRESENT) )