mm, vmalloc: move get_vmalloc_info() to vmalloc.c

Now get_vmalloc_info() is in fs/proc/mmu.c.  There is no reason that this
code must be here and it's implementation needs vmlist_lock and it iterate
a vmlist which may be internal data structure for vmalloc.

It is preferable that vmlist_lock and vmlist is only used in vmalloc.c
for maintainability. So move the code to vmalloc.c

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 44 insertions, 0 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 0f751f2068c..1d9878b7cf5 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2645,5 +2645,49 @@ static int __init proc_vmalloc_init(void)
 	return 0;
 }
 module_init(proc_vmalloc_init);
+
+void get_vmalloc_info(struct vmalloc_info *vmi)
+{
+	struct vm_struct *vma;
+	unsigned long free_area_size;
+	unsigned long prev_end;
+
+	vmi->used = 0;
+
+	if (!vmlist) {
+		vmi->largest_chunk = VMALLOC_TOTAL;
+	} else {
+		vmi->largest_chunk = 0;
+
+		prev_end = VMALLOC_START;
+
+		read_lock(&vmlist_lock);
+
+		for (vma = vmlist; vma; vma = vma->next) {
+			unsigned long addr = (unsigned long) vma->addr;
+
+			/*
+			 * Some archs keep another range for modules in vmlist
+			 */
+			if (addr < VMALLOC_START)
+				continue;
+			if (addr >= VMALLOC_END)
+				break;
+
+			vmi->used += vma->size;
+
+			free_area_size = addr - prev_end;
+			if (vmi->largest_chunk < free_area_size)
+				vmi->largest_chunk = free_area_size;
+
+			prev_end = vma->size + addr;
+		}
+
+		if (VMALLOC_END - prev_end > vmi->largest_chunk)
+			vmi->largest_chunk = VMALLOC_END - prev_end;
+
+		read_unlock(&vmlist_lock);
+	}
+}
 #endif