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-rw-r--r--cleopatre/linux-2.6.25.10-spc300/arch/s390/mm/mmap.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/cleopatre/linux-2.6.25.10-spc300/arch/s390/mm/mmap.c b/cleopatre/linux-2.6.25.10-spc300/arch/s390/mm/mmap.c
new file mode 100644
index 0000000000..5932a82454
--- /dev/null
+++ b/cleopatre/linux-2.6.25.10-spc300/arch/s390/mm/mmap.c
@@ -0,0 +1,151 @@
+/*
+ * linux/arch/s390/mm/mmap.c
+ *
+ * flexible mmap layout support
+ *
+ * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ *
+ * Started by Ingo Molnar <mingo@elte.hu>
+ */
+
+#include <linux/personality.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <asm/pgalloc.h>
+
+/*
+ * Top of mmap area (just below the process stack).
+ *
+ * Leave an at least ~128 MB hole.
+ */
+#define MIN_GAP (128*1024*1024)
+#define MAX_GAP (TASK_SIZE/6*5)
+
+static inline unsigned long mmap_base(void)
+{
+ unsigned long gap = current->signal->rlim[RLIMIT_STACK].rlim_cur;
+
+ if (gap < MIN_GAP)
+ gap = MIN_GAP;
+ else if (gap > MAX_GAP)
+ gap = MAX_GAP;
+
+ return TASK_SIZE - (gap & PAGE_MASK);
+}
+
+static inline int mmap_is_legacy(void)
+{
+#ifdef CONFIG_64BIT
+ /*
+ * Force standard allocation for 64 bit programs.
+ */
+ if (!test_thread_flag(TIF_31BIT))
+ return 1;
+#endif
+ return sysctl_legacy_va_layout ||
+ (current->personality & ADDR_COMPAT_LAYOUT) ||
+ current->signal->rlim[RLIMIT_STACK].rlim_cur == RLIM_INFINITY;
+}
+
+#ifndef CONFIG_64BIT
+
+/*
+ * This function, called very early during the creation of a new
+ * process VM image, sets up which VM layout function to use:
+ */
+void arch_pick_mmap_layout(struct mm_struct *mm)
+{
+ /*
+ * Fall back to the standard layout if the personality
+ * bit is set, or if the expected stack growth is unlimited:
+ */
+ if (mmap_is_legacy()) {
+ mm->mmap_base = TASK_UNMAPPED_BASE;
+ mm->get_unmapped_area = arch_get_unmapped_area;
+ mm->unmap_area = arch_unmap_area;
+ } else {
+ mm->mmap_base = mmap_base();
+ mm->get_unmapped_area = arch_get_unmapped_area_topdown;
+ mm->unmap_area = arch_unmap_area_topdown;
+ }
+}
+EXPORT_SYMBOL_GPL(arch_pick_mmap_layout);
+
+#else
+
+static unsigned long
+s390_get_unmapped_area(struct file *filp, unsigned long addr,
+ unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+ struct mm_struct *mm = current->mm;
+ int rc;
+
+ addr = arch_get_unmapped_area(filp, addr, len, pgoff, flags);
+ if (addr & ~PAGE_MASK)
+ return addr;
+ if (unlikely(mm->context.asce_limit < addr + len)) {
+ rc = crst_table_upgrade(mm, addr + len);
+ if (rc)
+ return (unsigned long) rc;
+ }
+ return addr;
+}
+
+static unsigned long
+s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
+ const unsigned long len, const unsigned long pgoff,
+ const unsigned long flags)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long addr = addr0;
+ int rc;
+
+ addr = arch_get_unmapped_area_topdown(filp, addr, len, pgoff, flags);
+ if (addr & ~PAGE_MASK)
+ return addr;
+ if (unlikely(mm->context.asce_limit < addr + len)) {
+ rc = crst_table_upgrade(mm, addr + len);
+ if (rc)
+ return (unsigned long) rc;
+ }
+ return addr;
+}
+/*
+ * This function, called very early during the creation of a new
+ * process VM image, sets up which VM layout function to use:
+ */
+void arch_pick_mmap_layout(struct mm_struct *mm)
+{
+ /*
+ * Fall back to the standard layout if the personality
+ * bit is set, or if the expected stack growth is unlimited:
+ */
+ if (mmap_is_legacy()) {
+ mm->mmap_base = TASK_UNMAPPED_BASE;
+ mm->get_unmapped_area = s390_get_unmapped_area;
+ mm->unmap_area = arch_unmap_area;
+ } else {
+ mm->mmap_base = mmap_base();
+ mm->get_unmapped_area = s390_get_unmapped_area_topdown;
+ mm->unmap_area = arch_unmap_area_topdown;
+ }
+}
+EXPORT_SYMBOL_GPL(arch_pick_mmap_layout);
+
+#endif