From: Yoshinori Sato <ysato@users.sourceforge.jp>
o include/asm-h8300/mmu.h:
Changeset 1.2053 support
o mm/nommu.c:
add __vm_enough_memory
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/include/asm-h8300/mmu.h | 13 -----
25-akpm/mm/nommu.c | 93 +++++++++++++++++++++++++++++++++++++++-
2 files changed, 93 insertions(+), 13 deletions(-)
diff -puN include/asm-h8300/mmu.h~h8-300-mm-update include/asm-h8300/mmu.h
--- 25/include/asm-h8300/mmu.h~h8-300-mm-update 2005-01-16 14:42:58.556477584 -0800
+++ 25-akpm/include/asm-h8300/mmu.h 2005-01-16 14:42:58.562476672 -0800
@@ -3,19 +3,8 @@
/* Copyright (C) 2002, David McCullough <davidm@snapgear.com> */
-struct mm_rblock_struct {
- int size;
- int refcount;
- void *kblock;
-};
-
-struct mm_tblock_struct {
- struct mm_rblock_struct *rblock;
- struct mm_tblock_struct *next;
-};
-
typedef struct {
- struct mm_tblock_struct tblock;
+ struct vm_list_struct *vmlist;
unsigned long end_brk;
} mm_context_t;
diff -puN mm/nommu.c~h8-300-mm-update mm/nommu.c
--- 25/mm/nommu.c~h8-300-mm-update 2005-01-16 14:42:58.558477280 -0800
+++ 25-akpm/mm/nommu.c 2005-01-16 14:42:58.563476520 -0800
@@ -41,8 +41,12 @@ int sysctl_overcommit_ratio = 50; /* def
int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT;
int heap_stack_gap = 0;
-EXPORT_SYMBOL(sysctl_max_map_count);
EXPORT_SYMBOL(mem_map);
+EXPORT_SYMBOL(sysctl_max_map_count);
+EXPORT_SYMBOL(sysctl_overcommit_memory);
+EXPORT_SYMBOL(sysctl_overcommit_ratio);
+EXPORT_SYMBOL(vm_committed_space);
+EXPORT_SYMBOL(__vm_enough_memory);
/* list of shareable VMAs */
struct rb_root nommu_vma_tree = RB_ROOT;
@@ -968,3 +972,90 @@ void unmap_mapping_range(struct address_
int even_cows)
{
}
+
+/*
+ * Check that a process has enough memory to allocate a new virtual
+ * mapping. 0 means there is enough memory for the allocation to
+ * succeed and -ENOMEM implies there is not.
+ *
+ * We currently support three overcommit policies, which are set via the
+ * vm.overcommit_memory sysctl. See Documentation/vm/overcommit-accounting
+ *
+ * Strict overcommit modes added 2002 Feb 26 by Alan Cox.
+ * Additional code 2002 Jul 20 by Robert Love.
+ *
+ * cap_sys_admin is 1 if the process has admin privileges, 0 otherwise.
+ *
+ * Note this is a helper function intended to be used by LSMs which
+ * wish to use this logic.
+ */
+int __vm_enough_memory(long pages, int cap_sys_admin)
+{
+ unsigned long free, allowed;
+
+ vm_acct_memory(pages);
+
+ /*
+ * Sometimes we want to use more memory than we have
+ */
+ if (sysctl_overcommit_memory == OVERCOMMIT_ALWAYS)
+ return 0;
+
+ if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
+ unsigned long n;
+
+ free = get_page_cache_size();
+ free += nr_swap_pages;
+
+ /*
+ * Any slabs which are created with the
+ * SLAB_RECLAIM_ACCOUNT flag claim to have contents
+ * which are reclaimable, under pressure. The dentry
+ * cache and most inode caches should fall into this
+ */
+ free += atomic_read(&slab_reclaim_pages);
+
+ /*
+ * Leave the last 3% for root
+ */
+ if (!cap_sys_admin)
+ free -= free / 32;
+
+ if (free > pages)
+ return 0;
+
+ /*
+ * nr_free_pages() is very expensive on large systems,
+ * only call if we're about to fail.
+ */
+ n = nr_free_pages();
+ if (!cap_sys_admin)
+ n -= n / 32;
+ free += n;
+
+ if (free > pages)
+ return 0;
+ vm_unacct_memory(pages);
+ return -ENOMEM;
+ }
+
+ allowed = totalram_pages * sysctl_overcommit_ratio / 100;
+ /*
+ * Leave the last 3% for root
+ */
+ if (!cap_sys_admin)
+ allowed -= allowed / 32;
+ allowed += total_swap_pages;
+
+ /* Don't let a single process grow too big:
+ leave 3% of the size of this process for other processes */
+ allowed -= current->mm->total_vm / 32;
+
+ if (atomic_read(&vm_committed_space) < allowed)
+ return 0;
+
+ vm_unacct_memory(pages);
+
+ return -ENOMEM;
+}
+
_