[PATCH] freepgt: remove MM_VM_SIZE(mm)

There's only one usage of MM_VM_SIZE(mm) left, and it's a troublesome macro
because mm doesn't contain the (32-bit emulation?) info needed.  But it too is
only needed because we ignore the end from the vma list.

We could make flush_pgtables return that end, or unmap_vmas.  Choose the
latter, since it's a natural fit with unmap_mapping_range_vma needing to know
its restart addr.  This does make more than minimal change, but if unmap_vmas
had returned the end before, this is how we'd have done it, rather than
storing the break_addr in zap_details.

unmap_vmas used to return count of vmas scanned, but that's just debug which
hasn't been useful in a while; and if we want the map_count 0 on exit check
back, it can easily come from the final remove_vm_struct loop.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

4 files changed, 2 insertions, 21 deletions

diff --git a/include/asm-ia64/processor.h b/include/asm-ia64/processor.h
index 8769dd9df369..2807f8d766d4 100644
--- a/include/asm-ia64/processor.h
+++ b/include/asm-ia64/processor.h
@@ -43,14 +43,6 @@
 #define TASK_SIZE               (current->thread.task_size)
 
 /*
- * MM_VM_SIZE(mm) gives the maximum address (plus 1) which may contain a mapping for
- * address-space MM.  Note that with 32-bit tasks, this is still DEFAULT_TASK_SIZE,
- * because the kernel may have installed helper-mappings above TASK_SIZE.  For example,
- * for x86 emulation, the LDT and GDT are mapped above TASK_SIZE.
- */
-#define MM_VM_SIZE(mm)          DEFAULT_TASK_SIZE
-
-/*
  * This decides where the kernel will search for a free chunk of vm
  * space during mmap's.
  */
diff --git a/include/asm-ppc64/processor.h b/include/asm-ppc64/processor.h
index cae65b30adb8..0035efe2db2b 100644
--- a/include/asm-ppc64/processor.h
+++ b/include/asm-ppc64/processor.h
@@ -542,10 +542,6 @@ extern struct task_struct *last_task_used_altivec;
 #define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
                 TASK_SIZE_USER32 : TASK_SIZE_USER64)
 
-/* We can't actually tell the TASK_SIZE given just the mm, but default
- * to the 64-bit case to make sure that enough gets cleaned up. */
-#define MM_VM_SIZE(mm)  TASK_SIZE_USER64
-
 /* This decides where the kernel will search for a free chunk of vm
  * space during mmap's.
  */
diff --git a/include/asm-s390/processor.h b/include/asm-s390/processor.h
index cbbd11471672..88c272ca48bf 100644
--- a/include/asm-s390/processor.h
+++ b/include/asm-s390/processor.h
@@ -74,8 +74,6 @@ extern struct task_struct *last_task_used_math;
 
 #endif /* __s390x__ */
 
-#define MM_VM_SIZE(mm)          DEFAULT_TASK_SIZE
-
 #define HAVE_ARCH_PICK_MMAP_LAYOUT
 
 typedef struct {
diff --git a/include/linux/mm.h b/include/linux/mm.h
index c3f6c39d41d0..59eca28b5ae2 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -37,10 +37,6 @@ extern int sysctl_legacy_va_layout;
 #include <asm/processor.h>
 #include <asm/atomic.h>
 
-#ifndef MM_VM_SIZE
-#define MM_VM_SIZE(mm)  ((TASK_SIZE + PGDIR_SIZE - 1) & PGDIR_MASK)
-#endif
-
 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
 
 /*
@@ -582,13 +578,12 @@ struct zap_details {
         pgoff_t first_index;                    /* Lowest page->index to unmap */
         pgoff_t last_index;                     /* Highest page->index to unmap */
         spinlock_t *i_mmap_lock;                /* For unmap_mapping_range: */
-        unsigned long break_addr;               /* Where unmap_vmas stopped */
         unsigned long truncate_count;           /* Compare vm_truncate_count */
 };
 
-void zap_page_range(struct vm_area_struct *vma, unsigned long address,
+unsigned long zap_page_range(struct vm_area_struct *vma, unsigned long address,
                 unsigned long size, struct zap_details *);
-int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm,
+unsigned long unmap_vmas(struct mmu_gather **tlb, struct mm_struct *mm,
                 struct vm_area_struct *start_vma, unsigned long start_addr,
                 unsigned long end_addr, unsigned long *nr_accounted,
                 struct zap_details *);