lguest: replace lguest_arch with lg_cpu_arch.

The fields found in lguest_arch are not really per-guest,
but per-cpu (gdt, idt, etc). So this patch turns lguest_arch
into lg_cpu_arch.

It makes sense to have a per-guest per-arch struct, but this
can be addressed later, when the need arrives.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 22 insertions, 20 deletions

diff --git a/drivers/lguest/segments.c b/drivers/lguest/segments.c
index 9e189cbec7dd..02138450ecf5 100644
--- a/drivers/lguest/segments.c
+++ b/drivers/lguest/segments.c
@@ -58,7 +58,7 @@ static int ignored_gdt(unsigned int num)
  * Protection Fault in the Switcher when it restores a Guest segment register
  * which tries to use that entry.  Then we kill the Guest for causing such a
  * mess: the message will be "unhandled trap 256". */
-static void fixup_gdt_table(struct lguest *lg, unsigned start, unsigned end)
+static void fixup_gdt_table(struct lg_cpu *cpu, unsigned start, unsigned end)
 {
         unsigned int i;
 
@@ -71,14 +71,14 @@ static void fixup_gdt_table(struct lguest *lg, unsigned start, unsigned end)
                 /* Segment descriptors contain a privilege level: the Guest is
                  * sometimes careless and leaves this as 0, even though it's
                  * running at privilege level 1.  If so, we fix it here. */
-                if ((lg->arch.gdt[i].b & 0x00006000) == 0)
-                        lg->arch.gdt[i].b |= (GUEST_PL << 13);
+                if ((cpu->arch.gdt[i].b & 0x00006000) == 0)
+                        cpu->arch.gdt[i].b |= (GUEST_PL << 13);
 
                 /* Each descriptor has an "accessed" bit.  If we don't set it
                  * now, the CPU will try to set it when the Guest first loads
                  * that entry into a segment register.  But the GDT isn't
                  * writable by the Guest, so bad things can happen. */
-                lg->arch.gdt[i].b |= 0x00000100;
+                cpu->arch.gdt[i].b |= 0x00000100;
         }
 }
 
@@ -109,31 +109,31 @@ void setup_default_gdt_entries(struct lguest_ro_state *state)
 
 /* This routine sets up the initial Guest GDT for booting.  All entries start
  * as 0 (unusable). */
-void setup_guest_gdt(struct lguest *lg)
+void setup_guest_gdt(struct lg_cpu *cpu)
 {
         /* Start with full 0-4G segments... */
-        lg->arch.gdt[GDT_ENTRY_KERNEL_CS] = FULL_EXEC_SEGMENT;
-        lg->arch.gdt[GDT_ENTRY_KERNEL_DS] = FULL_SEGMENT;
+        cpu->arch.gdt[GDT_ENTRY_KERNEL_CS] = FULL_EXEC_SEGMENT;
+        cpu->arch.gdt[GDT_ENTRY_KERNEL_DS] = FULL_SEGMENT;
         /* ...except the Guest is allowed to use them, so set the privilege
          * level appropriately in the flags. */
-        lg->arch.gdt[GDT_ENTRY_KERNEL_CS].b |= (GUEST_PL << 13);
-        lg->arch.gdt[GDT_ENTRY_KERNEL_DS].b |= (GUEST_PL << 13);
+        cpu->arch.gdt[GDT_ENTRY_KERNEL_CS].b |= (GUEST_PL << 13);
+        cpu->arch.gdt[GDT_ENTRY_KERNEL_DS].b |= (GUEST_PL << 13);
 }
 
 /*H:650 An optimization of copy_gdt(), for just the three "thead-local storage"
  * entries. */
-void copy_gdt_tls(const struct lguest *lg, struct desc_struct *gdt)
+void copy_gdt_tls(const struct lg_cpu *cpu, struct desc_struct *gdt)
 {
         unsigned int i;
 
         for (i = GDT_ENTRY_TLS_MIN; i <= GDT_ENTRY_TLS_MAX; i++)
-                gdt[i] = lg->arch.gdt[i];
+                gdt[i] = cpu->arch.gdt[i];
 }
 
 /*H:640 When the Guest is run on a different CPU, or the GDT entries have
  * changed, copy_gdt() is called to copy the Guest's GDT entries across to this
  * CPU's GDT. */
-void copy_gdt(const struct lguest *lg, struct desc_struct *gdt)
+void copy_gdt(const struct lg_cpu *cpu, struct desc_struct *gdt)
 {
         unsigned int i;
 
@@ -141,21 +141,22 @@ void copy_gdt(const struct lguest *lg, struct desc_struct *gdt)
          * replaced.  See ignored_gdt() above. */
         for (i = 0; i < GDT_ENTRIES; i++)
                 if (!ignored_gdt(i))
-                        gdt[i] = lg->arch.gdt[i];
+                        gdt[i] = cpu->arch.gdt[i];
 }
 
 /*H:620 This is where the Guest asks us to load a new GDT (LHCALL_LOAD_GDT).
  * We copy it from the Guest and tweak the entries. */
-void load_guest_gdt(struct lguest *lg, unsigned long table, u32 num)
+void load_guest_gdt(struct lg_cpu *cpu, unsigned long table, u32 num)
 {
+        struct lguest *lg = cpu->lg;
         /* We assume the Guest has the same number of GDT entries as the
          * Host, otherwise we'd have to dynamically allocate the Guest GDT. */
-        if (num > ARRAY_SIZE(lg->arch.gdt))
+        if (num > ARRAY_SIZE(cpu->arch.gdt))
                 kill_guest(lg, "too many gdt entries %i", num);
 
         /* We read the whole thing in, then fix it up. */
-        __lgread(lg, lg->arch.gdt, table, num * sizeof(lg->arch.gdt[0]));
-        fixup_gdt_table(lg, 0, ARRAY_SIZE(lg->arch.gdt));
+        __lgread(lg, cpu->arch.gdt, table, num * sizeof(cpu->arch.gdt[0]));
+        fixup_gdt_table(cpu, 0, ARRAY_SIZE(cpu->arch.gdt));
         /* Mark that the GDT changed so the core knows it has to copy it again,
          * even if the Guest is run on the same CPU. */
         lg->changed |= CHANGED_GDT;
@@ -165,12 +166,13 @@ void load_guest_gdt(struct lguest *lg, unsigned long table, u32 num)
  * Remember that this happens on every context switch, so it's worth
  * optimizing.  But wouldn't it be neater to have a single hypercall to cover
  * both cases? */
-void guest_load_tls(struct lguest *lg, unsigned long gtls)
+void guest_load_tls(struct lg_cpu *cpu, unsigned long gtls)
 {
-        struct desc_struct *tls = &lg->arch.gdt[GDT_ENTRY_TLS_MIN];
+        struct desc_struct *tls = &cpu->arch.gdt[GDT_ENTRY_TLS_MIN];
+        struct lguest *lg = cpu->lg;
 
         __lgread(lg, tls, gtls, sizeof(*tls)*GDT_ENTRY_TLS_ENTRIES);
-        fixup_gdt_table(lg, GDT_ENTRY_TLS_MIN, GDT_ENTRY_TLS_MAX+1);
+        fixup_gdt_table(cpu, GDT_ENTRY_TLS_MIN, GDT_ENTRY_TLS_MAX+1);
         /* Note that just the TLS entries have changed. */
         lg->changed |= CHANGED_GDT_TLS;
 }