Update to 3.4-final.
[linux-flexiantxendom0-3.2.10.git] / fs / drop_caches.c
index 44d725f..c00e055 100644 (file)
@@ -8,67 +8,58 @@
 #include <linux/writeback.h>
 #include <linux/sysctl.h>
 #include <linux/gfp.h>
+#include "internal.h"
 
 /* A global variable is a bit ugly, but it keeps the code simple */
 int sysctl_drop_caches;
 
-static void drop_pagecache_sb(struct super_block *sb)
+static void drop_pagecache_sb(struct super_block *sb, void *unused)
 {
        struct inode *inode, *toput_inode = NULL;
 
-       spin_lock(&inode_lock);
+       spin_lock(&inode_sb_list_lock);
        list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
-               if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW))
-                       continue;
-               if (inode->i_mapping->nrpages == 0)
+               spin_lock(&inode->i_lock);
+               if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
+                   (inode->i_mapping->nrpages == 0)) {
+                       spin_unlock(&inode->i_lock);
                        continue;
+               }
                __iget(inode);
-               spin_unlock(&inode_lock);
-               __invalidate_mapping_pages(inode->i_mapping, 0, -1, true);
+               spin_unlock(&inode->i_lock);
+               spin_unlock(&inode_sb_list_lock);
+               invalidate_mapping_pages(inode->i_mapping, 0, -1);
                iput(toput_inode);
                toput_inode = inode;
-               spin_lock(&inode_lock);
+               spin_lock(&inode_sb_list_lock);
        }
-       spin_unlock(&inode_lock);
+       spin_unlock(&inode_sb_list_lock);
        iput(toput_inode);
 }
 
-static void drop_pagecache(void)
-{
-       struct super_block *sb;
-
-       spin_lock(&sb_lock);
-restart:
-       list_for_each_entry(sb, &super_blocks, s_list) {
-               sb->s_count++;
-               spin_unlock(&sb_lock);
-               down_read(&sb->s_umount);
-               if (sb->s_root)
-                       drop_pagecache_sb(sb);
-               up_read(&sb->s_umount);
-               spin_lock(&sb_lock);
-               if (__put_super_and_need_restart(sb))
-                       goto restart;
-       }
-       spin_unlock(&sb_lock);
-}
-
 static void drop_slab(void)
 {
        int nr_objects;
+       struct shrink_control shrink = {
+               .gfp_mask = GFP_KERNEL,
+       };
 
        do {
-               nr_objects = shrink_slab(1000, GFP_KERNEL, 1000);
+               nr_objects = shrink_slab(&shrink, 1000, 1000);
        } while (nr_objects > 10);
 }
 
 int drop_caches_sysctl_handler(ctl_table *table, int write,
-       struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
+       void __user *buffer, size_t *length, loff_t *ppos)
 {
-       proc_dointvec_minmax(table, write, file, buffer, length, ppos);
+       int ret;
+
+       ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
+       if (ret)
+               return ret;
        if (write) {
                if (sysctl_drop_caches & 1)
-                       drop_pagecache();
+                       iterate_supers(drop_pagecache_sb, NULL);
                if (sysctl_drop_caches & 2)
                        drop_slab();
        }