[PATCH] ppc64: Abolish ioremap_mm

Currently ppc64 has two mm_structs for the kernel, init_mm and also
ioremap_mm.  The latter really isn't necessary: this patch abolishes it,
instead restricting vmallocs to the lower 1TB of the init_mm's range and
placing io mappings in the upper 1TB.  This simplifies the code in a number
of places and eliminates an unecessary set of pagetables.  It also tweaks
the unmap/free path a little, allowing us to remove the unmap_im_area() set
of page table walkers, replacing them with unmap_vm_area().

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

4 files changed, 9 insertions, 24 deletions

diff --git a/include/asm-ppc64/imalloc.h b/include/asm-ppc64/imalloc.h
index 3a45e918bf16..e46ff68a6e41 100644
--- a/include/asm-ppc64/imalloc.h
+++ b/include/asm-ppc64/imalloc.h
@@ -4,9 +4,9 @@
 /*
  * Define the address range of the imalloc VM area.
  */
-#define PHBS_IO_BASE      IOREGIONBASE
-#define IMALLOC_BASE      (IOREGIONBASE + 0x80000000ul) /* Reserve 2 gigs for PHBs */
-#define IMALLOC_END       (IOREGIONBASE + EADDR_MASK)
+#define PHBS_IO_BASE      VMALLOC_END
+#define IMALLOC_BASE      (PHBS_IO_BASE + 0x80000000ul) /* Reserve 2 gigs for PHBs */
+#define IMALLOC_END       (VMALLOC_START + EADDR_MASK)
 
 
 /* imalloc region types */
@@ -18,7 +18,9 @@
 
 extern struct vm_struct * im_get_free_area(unsigned long size);
 extern struct vm_struct * im_get_area(unsigned long v_addr, unsigned long size,
-                        int region_type);
-unsigned long im_free(void *addr);
+                                      int region_type);
+extern void im_free(void *addr);
+
+extern unsigned long ioremap_bot;
 
 #endif /* _PPC64_IMALLOC_H */
diff --git a/include/asm-ppc64/page.h b/include/asm-ppc64/page.h
index bcd21789d3b7..257d87eb7c34 100644
--- a/include/asm-ppc64/page.h
+++ b/include/asm-ppc64/page.h
@@ -202,9 +202,7 @@ extern u64 ppc64_pft_size;		/* Log 2 of page table size */
 #define PAGE_OFFSET     ASM_CONST(0xC000000000000000)
 #define KERNELBASE      PAGE_OFFSET
 #define VMALLOCBASE     ASM_CONST(0xD000000000000000)
-#define IOREGIONBASE    ASM_CONST(0xE000000000000000)
 
-#define IO_REGION_ID       (IOREGIONBASE >> REGION_SHIFT)
 #define VMALLOC_REGION_ID  (VMALLOCBASE >> REGION_SHIFT)
 #define KERNEL_REGION_ID   (KERNELBASE >> REGION_SHIFT)
 #define USER_REGION_ID     (0UL)
diff --git a/include/asm-ppc64/pgtable.h b/include/asm-ppc64/pgtable.h
index 264c4f7993be..46cf61c2ff69 100644
--- a/include/asm-ppc64/pgtable.h
+++ b/include/asm-ppc64/pgtable.h
@@ -53,7 +53,8 @@
  * Define the address range of the vmalloc VM area.
  */
 #define VMALLOC_START (0xD000000000000000ul)
-#define VMALLOC_END   (VMALLOC_START + EADDR_MASK)
+#define VMALLOC_SIZE  (0x10000000000UL)
+#define VMALLOC_END   (VMALLOC_START + VMALLOC_SIZE)
 
 /*
  * Bits in a linux-style PTE.  These match the bits in the
@@ -239,9 +240,6 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
 /* This now only contains the vmalloc pages */
 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
 
-/* to find an entry in the ioremap page-table-directory */
-#define pgd_offset_i(address) (ioremap_pgd + pgd_index(address))
-
 /*
  * The following only work if pte_present() is true.
  * Undefined behaviour if not..
@@ -459,15 +457,12 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr,
 #define __HAVE_ARCH_PTE_SAME
 #define pte_same(A,B)   (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HPTEFLAGS) == 0)
 
-extern unsigned long ioremap_bot, ioremap_base;
-
 #define pmd_ERROR(e) \
         printk("%s:%d: bad pmd %08x.\n", __FILE__, __LINE__, pmd_val(e))
 #define pgd_ERROR(e) \
         printk("%s:%d: bad pgd %08x.\n", __FILE__, __LINE__, pgd_val(e))
 
 extern pgd_t swapper_pg_dir[];
-extern pgd_t ioremap_dir[];
 
 extern void paging_init(void);
 
diff --git a/include/asm-ppc64/processor.h b/include/asm-ppc64/processor.h
index 809c634ba1df..3084099086a8 100644
--- a/include/asm-ppc64/processor.h
+++ b/include/asm-ppc64/processor.h
@@ -430,16 +430,6 @@ struct thread_struct {
 }
 
 /*
- * Note: the vm_start and vm_end fields here should *not*
- * be in kernel space.  (Could vm_end == vm_start perhaps?)
- */
-#define IOREMAP_MMAP { &ioremap_mm, 0, 0x1000, NULL, \
-                    PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, \
-                    1, NULL, NULL }
-
-extern struct mm_struct ioremap_mm;
-
-/*
  * Return saved PC of a blocked thread. For now, this is the "user" PC
  */
 #define thread_saved_pc(tsk)    \