7 files changed, 93 insertions, 11 deletions

diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
index 32c4b0e35b37..3de7f84b53c2 100644
--- a/arch/arm/mm/mmap.c
+++ b/arch/arm/mm/mmap.c
@@ -73,7 +73,12 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
                     (!vma || addr + len <= vma->vm_start))
                         return addr;
         }
-        start_addr = addr = mm->free_area_cache;
+        if (len > mm->cached_hole_size) {
+                start_addr = addr = mm->free_area_cache;
+        } else {
+                start_addr = addr = TASK_UNMAPPED_BASE;
+                mm->cached_hole_size = 0;
+        }
 
 full_search:
         if (do_align)
@@ -90,6 +95,7 @@ full_search:
                          */
                         if (start_addr != TASK_UNMAPPED_BASE) {
                                 start_addr = addr = TASK_UNMAPPED_BASE;
+                                mm->cached_hole_size = 0;
                                 goto full_search;
                         }
                         return -ENOMEM;
@@ -101,6 +107,8 @@ full_search:
                         mm->free_area_cache = addr + len;
                         return addr;
                 }
+                if (addr + mm->cached_hole_size < vma->vm_start)
+                        mm->cached_hole_size = vma->vm_start - addr;
                 addr = vma->vm_end;
                 if (do_align)
                         addr = COLOUR_ALIGN(addr, pgoff);
diff --git a/arch/i386/mm/hugetlbpage.c b/arch/i386/mm/hugetlbpage.c
index 5aa06001a4bd..3b099f32b948 100644
--- a/arch/i386/mm/hugetlbpage.c
+++ b/arch/i386/mm/hugetlbpage.c
@@ -140,7 +140,12 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
         struct vm_area_struct *vma;
         unsigned long start_addr;
 
-        start_addr = mm->free_area_cache;
+        if (len > mm->cached_hole_size) {
+                start_addr = mm->free_area_cache;
+        } else {
+                start_addr = TASK_UNMAPPED_BASE;
+                mm->cached_hole_size = 0;
+        }
 
 full_search:
         addr = ALIGN(start_addr, HPAGE_SIZE);
@@ -154,6 +159,7 @@ full_search:
                          */
                         if (start_addr != TASK_UNMAPPED_BASE) {
                                 start_addr = TASK_UNMAPPED_BASE;
+                                mm->cached_hole_size = 0;
                                 goto full_search;
                         }
                         return -ENOMEM;
@@ -162,6 +168,8 @@ full_search:
                         mm->free_area_cache = addr + len;
                         return addr;
                 }
+                if (addr + mm->cached_hole_size < vma->vm_start)
+                        mm->cached_hole_size = vma->vm_start - addr;
                 addr = ALIGN(vma->vm_end, HPAGE_SIZE);
         }
 }
@@ -173,12 +181,17 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,
         struct mm_struct *mm = current->mm;
         struct vm_area_struct *vma, *prev_vma;
         unsigned long base = mm->mmap_base, addr = addr0;
+        unsigned long largest_hole = mm->cached_hole_size;
         int first_time = 1;
 
         /* don't allow allocations above current base */
         if (mm->free_area_cache > base)
                 mm->free_area_cache = base;
 
+        if (len <= largest_hole) {
+                largest_hole = 0;
+                mm->free_area_cache  = base;
+        }
 try_again:
         /* make sure it can fit in the remaining address space */
         if (mm->free_area_cache < len)
@@ -199,13 +212,21 @@ try_again:
                  * vma->vm_start, use it:
                  */
                 if (addr + len <= vma->vm_start &&
-                                (!prev_vma || (addr >= prev_vma->vm_end)))
+                            (!prev_vma || (addr >= prev_vma->vm_end))) {
                         /* remember the address as a hint for next time */
-                        return (mm->free_area_cache = addr);
-                else
+                        mm->cached_hole_size = largest_hole;
+                        return (mm->free_area_cache = addr);
+                } else {
                         /* pull free_area_cache down to the first hole */
-                        if (mm->free_area_cache == vma->vm_end)
+                        if (mm->free_area_cache == vma->vm_end) {
                                 mm->free_area_cache = vma->vm_start;
+                                mm->cached_hole_size = largest_hole;
+                        }
+                }
+
+                /* remember the largest hole we saw so far */
+                if (addr + largest_hole < vma->vm_start)
+                        largest_hole = vma->vm_start - addr;
 
                 /* try just below the current vma->vm_start */
                 addr = (vma->vm_start - len) & HPAGE_MASK;
@@ -218,6 +239,7 @@ fail:
          */
         if (first_time) {
                 mm->free_area_cache = base;
+                largest_hole = 0;
                 first_time = 0;
                 goto try_again;
         }
@@ -228,6 +250,7 @@ fail:
          * allocations.
          */
         mm->free_area_cache = TASK_UNMAPPED_BASE;
+        mm->cached_hole_size = ~0UL;
         addr = hugetlb_get_unmapped_area_bottomup(file, addr0,
                         len, pgoff, flags);
 
@@ -235,6 +258,7 @@ fail:
          * Restore the topdown base:
          */
         mm->free_area_cache = base;
+        mm->cached_hole_size = ~0UL;
 
         return addr;
 }
diff --git a/arch/ppc64/mm/hugetlbpage.c b/arch/ppc64/mm/hugetlbpage.c
index b4ab766f5980..fdcfe97c75c1 100644
--- a/arch/ppc64/mm/hugetlbpage.c
+++ b/arch/ppc64/mm/hugetlbpage.c
@@ -292,7 +292,12 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
                     && !is_hugepage_only_range(mm, addr,len))
                         return addr;
         }
-        start_addr = addr = mm->free_area_cache;
+        if (len > mm->cached_hole_size) {
+                start_addr = addr = mm->free_area_cache;
+        } else {
+                start_addr = addr = TASK_UNMAPPED_BASE;
+                mm->cached_hole_size = 0;
+        }
 
 full_search:
         vma = find_vma(mm, addr);
@@ -316,6 +321,8 @@ full_search:
                         mm->free_area_cache = addr + len;
                         return addr;
                 }
+                if (addr + mm->cached_hole_size < vma->vm_start)
+                        mm->cached_hole_size = vma->vm_start - addr;
                 addr = vma->vm_end;
                 vma = vma->vm_next;
         }
@@ -323,6 +330,7 @@ full_search:
         /* Make sure we didn't miss any holes */
         if (start_addr != TASK_UNMAPPED_BASE) {
                 start_addr = addr = TASK_UNMAPPED_BASE;
+                mm->cached_hole_size = 0;
                 goto full_search;
         }
         return -ENOMEM;
@@ -344,6 +352,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
         struct vm_area_struct *vma, *prev_vma;
         struct mm_struct *mm = current->mm;
         unsigned long base = mm->mmap_base, addr = addr0;
+        unsigned long largest_hole = mm->cached_hole_size;
         int first_time = 1;
 
         /* requested length too big for entire address space */
@@ -364,6 +373,10 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
                         return addr;
         }
 
+        if (len <= largest_hole) {
+                largest_hole = 0;
+                mm->free_area_cache = base;
+        }
 try_again:
         /* make sure it can fit in the remaining address space */
         if (mm->free_area_cache < len)
@@ -392,13 +405,21 @@ hugepage_recheck:
                  * vma->vm_start, use it:
                  */
                 if (addr+len <= vma->vm_start &&
-                                (!prev_vma || (addr >= prev_vma->vm_end)))
+                          (!prev_vma || (addr >= prev_vma->vm_end))) {
                         /* remember the address as a hint for next time */
-                        return (mm->free_area_cache = addr);
-                else
+                        mm->cached_hole_size = largest_hole;
+                        return (mm->free_area_cache = addr);
+                } else {
                         /* pull free_area_cache down to the first hole */
-                        if (mm->free_area_cache == vma->vm_end)
+                        if (mm->free_area_cache == vma->vm_end) {
                                 mm->free_area_cache = vma->vm_start;
+                                mm->cached_hole_size = largest_hole;
+                        }
+                }
+
+                /* remember the largest hole we saw so far */
+                if (addr + largest_hole < vma->vm_start)
+                        largest_hole = vma->vm_start - addr;
 
                 /* try just below the current vma->vm_start */
                 addr = vma->vm_start-len;
@@ -411,6 +432,7 @@ fail:
          */
         if (first_time) {
                 mm->free_area_cache = base;
+                largest_hole = 0;
                 first_time = 0;
                 goto try_again;
         }
@@ -421,11 +443,13 @@ fail:
          * allocations.
          */
         mm->free_area_cache = TASK_UNMAPPED_BASE;
+        mm->cached_hole_size = ~0UL;
         addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
         /*
          * Restore the topdown base:
          */
         mm->free_area_cache = base;
+        mm->cached_hole_size = ~0UL;
 
         return addr;
 }
diff --git a/arch/sh/kernel/sys_sh.c b/arch/sh/kernel/sys_sh.c
index df5ac294c379..917b2f32f260 100644
--- a/arch/sh/kernel/sys_sh.c
+++ b/arch/sh/kernel/sys_sh.c
@@ -79,6 +79,10 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
                     (!vma || addr + len <= vma->vm_start))
                         return addr;
         }
+        if (len <= mm->cached_hole_size) {
+                mm->cached_hole_size = 0;
+                mm->free_area_cache = TASK_UNMAPPED_BASE;
+        }
         if (flags & MAP_PRIVATE)
                 addr = PAGE_ALIGN(mm->free_area_cache);
         else
@@ -95,6 +99,7 @@ full_search:
                          */
                         if (start_addr != TASK_UNMAPPED_BASE) {
                                 start_addr = addr = TASK_UNMAPPED_BASE;
+                                mm->cached_hole_size = 0;
                                 goto full_search;
                         }
                         return -ENOMEM;
@@ -106,6 +111,9 @@ full_search:
                         mm->free_area_cache = addr + len;
                         return addr;
                 }
+                if (addr + mm->cached_hole_size < vma->vm_start)
+                        mm->cached_hole_size = vma->vm_start - addr;
+
                 addr = vma->vm_end;
                 if (!(flags & MAP_PRIVATE))
                         addr = COLOUR_ALIGN(addr);
diff --git a/arch/sparc64/kernel/sys_sparc.c b/arch/sparc64/kernel/sys_sparc.c
index 0077f02f4b37..5f8c822a2b4a 100644
--- a/arch/sparc64/kernel/sys_sparc.c
+++ b/arch/sparc64/kernel/sys_sparc.c
@@ -84,6 +84,10 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
                         return addr;
         }
 
+        if (len <= mm->cached_hole_size) {
+                mm->cached_hole_size = 0;
+                mm->free_area_cache = TASK_UNMAPPED_BASE;
+        }
         start_addr = addr = mm->free_area_cache;
 
         task_size -= len;
@@ -103,6 +107,7 @@ full_search:
                 if (task_size < addr) {
                         if (start_addr != TASK_UNMAPPED_BASE) {
                                 start_addr = addr = TASK_UNMAPPED_BASE;
+                                mm->cached_hole_size = 0;
                                 goto full_search;
                         }
                         return -ENOMEM;
@@ -114,6 +119,9 @@ full_search:
                         mm->free_area_cache = addr + len;
                         return addr;
                 }
+                if (addr + mm->cached_hole_size < vma->vm_start)
+                        mm->cached_hole_size = vma->vm_start - addr;
+
                 addr = vma->vm_end;
                 if (do_color_align)
                         addr = COLOUR_ALIGN(addr, pgoff);
diff --git a/arch/x86_64/ia32/ia32_aout.c b/arch/x86_64/ia32/ia32_aout.c
index 1965efc974dc..c12edf5d97f0 100644
--- a/arch/x86_64/ia32/ia32_aout.c
+++ b/arch/x86_64/ia32/ia32_aout.c
@@ -312,6 +312,7 @@ static int load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)
         current->mm->brk = ex.a_bss +
                 (current->mm->start_brk = N_BSSADDR(ex));
         current->mm->free_area_cache = TASK_UNMAPPED_BASE;
+        current->mm->cached_hole_size = 0;
 
         set_mm_counter(current->mm, rss, 0);
         current->mm->mmap = NULL;
diff --git a/arch/x86_64/kernel/sys_x86_64.c b/arch/x86_64/kernel/sys_x86_64.c
index d9798dd433fc..cc7821c68851 100644
--- a/arch/x86_64/kernel/sys_x86_64.c
+++ b/arch/x86_64/kernel/sys_x86_64.c
@@ -105,6 +105,11 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
                     (!vma || addr + len <= vma->vm_start))
                         return addr;
         }
+        if (((flags & MAP_32BIT) || test_thread_flag(TIF_IA32))
+            && len <= mm->cached_hole_size) {
+                mm->cached_hole_size = 0;
+                mm->free_area_cache = begin;
+        }
         addr = mm->free_area_cache;
         if (addr < begin) 
                 addr = begin; 
@@ -120,6 +125,7 @@ full_search:
                          */
                         if (start_addr != begin) {
                                 start_addr = addr = begin;
+                                mm->cached_hole_size = 0;
                                 goto full_search;
                         }
                         return -ENOMEM;
@@ -131,6 +137,9 @@ full_search:
                         mm->free_area_cache = addr + len;
                         return addr;
                 }
+                if (addr + mm->cached_hole_size < vma->vm_start)
+                        mm->cached_hole_size = vma->vm_start - addr;
+
                 addr = vma->vm_end;
         }
 }