[PATCH v2 1/3 gnumach] pmap: Refactor temporary mapping functions

[Damien Zammit]

---
 i386/i386at/model_dep.c | 73 +-------------------------------
 i386/intel/pmap.c       | 93 +++++++++++++++++++++++++++++++++++++++++
 i386/intel/pmap.h       |  6 +++
 3 files changed, 101 insertions(+), 71 deletions(-)

diff --git a/i386/i386at/model_dep.c b/i386/i386at/model_dep.c
index fe11bffc..98408c06 100644
--- a/i386/i386at/model_dep.c
+++ b/i386/i386at/model_dep.c
@@ -359,10 +359,6 @@ register_boot_data(const struct multiboot_raw_info *mbi)
 static void
 i386at_init(void)
 {
-       /* XXX move to intel/pmap.h */
-       extern pt_entry_t *kernel_page_dir;
-       int i;
-
        /*
         * Initialize the PIC prior to any possible call to an spl.
         */
@@ -448,47 +444,8 @@ i386at_init(void)
         */
        biosmem_setup();

-       /*
-        * We'll have to temporarily install a direct mapping
-        * between physical memory and low linear memory,
-        * until we start using our new kernel segment descriptors.
-        */
-#if INIT_VM_MIN_KERNEL_ADDRESS != LINEAR_MIN_KERNEL_ADDRESS
-       vm_offset_t delta = INIT_VM_MIN_KERNEL_ADDRESS - 
LINEAR_MIN_KERNEL_ADDRESS;
-       if ((vm_offset_t)(-delta) < delta)
-               delta = (vm_offset_t)(-delta);
-       int nb_direct = delta >> PDESHIFT;
-       for (i = 0; i < nb_direct; i++)
-               kernel_page_dir[lin2pdenum_cont(INIT_VM_MIN_KERNEL_ADDRESS) + 
i] =
-                       
kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS) + i];
-#endif
-       /* We need BIOS memory mapped at 0xc0000 & co for BIOS accesses */
-#if VM_MIN_KERNEL_ADDRESS != 0
-       kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS - 
VM_MIN_KERNEL_ADDRESS)] =
-               kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS)];
-#endif
+       pmap_make_temporary_mapping();

-#ifdef MACH_PV_PAGETABLES
-       for (i = 0; i < PDPNUM; i++)
-               pmap_set_page_readonly_init((void*) kernel_page_dir + i * 
INTEL_PGBYTES);
-#if PAE
-       pmap_set_page_readonly_init(kernel_pmap->pdpbase);
-#endif /* PAE */
-#endif /* MACH_PV_PAGETABLES */
-#if PAE
-#ifdef __x86_64__
-       set_cr3((unsigned long)_kvtophys(kernel_pmap->l4base));
-#else
-       set_cr3((unsigned long)_kvtophys(kernel_pmap->pdpbase));
-#endif
-#ifndef        MACH_HYP
-       if (!CPU_HAS_FEATURE(CPU_FEATURE_PAE))
-               panic("CPU doesn't have support for PAE.");
-       set_cr4(get_cr4() | CR4_PAE);
-#endif /* MACH_HYP */
-#else
-       set_cr3((unsigned long)_kvtophys(kernel_page_dir));
-#endif /* PAE */
 #ifndef        MACH_HYP
        /* Turn paging on.
         * Also set the WP bit so that on 486 or better processors
@@ -520,33 +477,7 @@ i386at_init(void)
        mp_desc_init(0);
 #endif // NCPUS

-#if INIT_VM_MIN_KERNEL_ADDRESS != LINEAR_MIN_KERNEL_ADDRESS
-       /* Get rid of the temporary direct mapping and flush it out of the TLB. 
 */
-       for (i = 0 ; i < nb_direct; i++) {
-#ifdef MACH_XEN
-#ifdef MACH_PSEUDO_PHYS
-               if 
(!hyp_mmu_update_pte(kv_to_ma(&kernel_page_dir[lin2pdenum_cont(VM_MIN_KERNEL_ADDRESS)
 + i]), 0))
-#else  /* MACH_PSEUDO_PHYS */
-               if (hyp_do_update_va_mapping(VM_MIN_KERNEL_ADDRESS + i * 
INTEL_PGBYTES, 0, UVMF_INVLPG | UVMF_ALL))
-#endif /* MACH_PSEUDO_PHYS */
-                       printf("couldn't unmap frame %d\n", i);
-#else  /* MACH_XEN */
-               kernel_page_dir[lin2pdenum_cont(INIT_VM_MIN_KERNEL_ADDRESS) + 
i] = 0;
-#endif /* MACH_XEN */
-       }
-#endif
-       /* Keep BIOS memory mapped */
-#if VM_MIN_KERNEL_ADDRESS != 0
-       kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS - 
VM_MIN_KERNEL_ADDRESS)] =
-               kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS)];
-#endif
-
-       /* Not used after boot, better give it back.  */
-#ifdef MACH_XEN
-       hyp_free_page(0, (void*) VM_MIN_KERNEL_ADDRESS);
-#endif /* MACH_XEN */
-
-       flush_tlb();
+       pmap_remove_temporary_mapping();

 #ifdef MACH_XEN
        hyp_p2m_init();
diff --git a/i386/intel/pmap.c b/i386/intel/pmap.c
index 0505cfa2..3c57d732 100644
--- a/i386/intel/pmap.c
+++ b/i386/intel/pmap.c
@@ -3009,3 +3009,96 @@ pmap_unmap_page_zero (void)
 #endif /* MACH_PV_PAGETABLES */
 }
 #endif /* __i386__ */
+
+void
+pmap_make_temporary_mapping(void)
+{
+       int i;
+
+       /*
+        * We'll have to temporarily install a direct mapping
+        * between physical memory and low linear memory,
+        * until we start using our new kernel segment descriptors.
+        */
+#if INIT_VM_MIN_KERNEL_ADDRESS != LINEAR_MIN_KERNEL_ADDRESS
+       vm_offset_t delta = INIT_VM_MIN_KERNEL_ADDRESS - 
LINEAR_MIN_KERNEL_ADDRESS;
+       if ((vm_offset_t)(-delta) < delta)
+               delta = (vm_offset_t)(-delta);
+       int nb_direct = delta >> PDESHIFT;
+       for (i = 0; i < nb_direct; i++)
+               kernel_page_dir[lin2pdenum_cont(INIT_VM_MIN_KERNEL_ADDRESS) + 
i] =
+                       
kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS) + i];
+#endif
+       /* We need BIOS memory mapped at 0xc0000 & co for BIOS accesses */
+#if VM_MIN_KERNEL_ADDRESS != 0
+       kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS - 
VM_MIN_KERNEL_ADDRESS)] =
+               kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS)];
+#endif
+
+#ifdef MACH_PV_PAGETABLES
+       for (i = 0; i < PDPNUM; i++)
+               pmap_set_page_readonly_init((void*) kernel_page_dir + i * 
INTEL_PGBYTES);
+#if PAE
+       pmap_set_page_readonly_init(kernel_pmap->pdpbase);
+#endif /* PAE */
+#endif /* MACH_PV_PAGETABLES */
+
+       pmap_set_page_dir();
+}
+
+void
+pmap_set_page_dir(void)
+{
+#if PAE
+#ifdef __x86_64__
+       set_cr3((unsigned long)_kvtophys(kernel_pmap->l4base));
+#else
+       set_cr3((unsigned long)_kvtophys(kernel_pmap->pdpbase));
+#endif
+#ifndef        MACH_HYP
+       if (!CPU_HAS_FEATURE(CPU_FEATURE_PAE))
+               panic("CPU doesn't have support for PAE.");
+       set_cr4(get_cr4() | CR4_PAE);
+#endif /* MACH_HYP */
+#else
+       set_cr3((unsigned long)_kvtophys(kernel_page_dir));
+#endif /* PAE */
+}
+
+void
+pmap_remove_temporary_mapping(void)
+{
+       int i;
+
+#if INIT_VM_MIN_KERNEL_ADDRESS != LINEAR_MIN_KERNEL_ADDRESS
+       vm_offset_t delta = INIT_VM_MIN_KERNEL_ADDRESS - 
LINEAR_MIN_KERNEL_ADDRESS;
+       if ((vm_offset_t)(-delta) < delta)
+               delta = (vm_offset_t)(-delta);
+       int nb_direct = delta >> PDESHIFT;
+       /* Get rid of the temporary direct mapping and flush it out of the TLB. 
 */
+       for (i = 0 ; i < nb_direct; i++) {
+#ifdef MACH_XEN
+#ifdef MACH_PSEUDO_PHYS
+               if 
(!hyp_mmu_update_pte(kv_to_ma(&kernel_page_dir[lin2pdenum_cont(VM_MIN_KERNEL_ADDRESS)
 + i]), 0))
+#else  /* MACH_PSEUDO_PHYS */
+               if (hyp_do_update_va_mapping(VM_MIN_KERNEL_ADDRESS + i * 
INTEL_PGBYTES, 0, UVMF_INVLPG | UVMF_ALL))
+#endif /* MACH_PSEUDO_PHYS */
+                       printf("couldn't unmap frame %d\n", i);
+#else  /* MACH_XEN */
+               kernel_page_dir[lin2pdenum_cont(INIT_VM_MIN_KERNEL_ADDRESS) + 
i] = 0;
+#endif /* MACH_XEN */
+       }
+#endif
+       /* Keep BIOS memory mapped */
+#if VM_MIN_KERNEL_ADDRESS != 0
+       kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS - 
VM_MIN_KERNEL_ADDRESS)] =
+               kernel_page_dir[lin2pdenum_cont(LINEAR_MIN_KERNEL_ADDRESS)];
+#endif
+
+       /* Not used after boot, better give it back.  */
+#ifdef MACH_XEN
+       hyp_free_page(0, (void*) VM_MIN_KERNEL_ADDRESS);
+#endif /* MACH_XEN */
+
+       flush_tlb();
+}
diff --git a/i386/intel/pmap.h b/i386/intel/pmap.h
index d6bf85fb..92247faa 100644
--- a/i386/intel/pmap.h
+++ b/i386/intel/pmap.h
@@ -475,6 +475,8 @@ pt_entry_t *pmap_pte(const pmap_t pmap, vm_offset_t addr);
 #define        pmap_attribute(pmap,addr,size,attr,value) \
                                        (KERN_INVALID_ADDRESS)

+extern pt_entry_t *kernel_page_dir;
+
 /*
  *  Bootstrap the system enough to run with virtual memory.
  *  Allocate the kernel page directory and page tables,
@@ -483,6 +485,10 @@ pt_entry_t *pmap_pte(const pmap_t pmap, vm_offset_t addr);
  */
 extern void pmap_bootstrap(void);

+extern void pmap_set_page_dir(void);
+extern void pmap_make_temporary_mapping(void);
+extern void pmap_remove_temporary_mapping(void);
+
 extern void pmap_unmap_page_zero (void);

 /*
--
2.34.1