f2fs: inject kmalloc failure

This patch injects kmalloc failure given a fault injection rate.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 29 insertions, 0 deletions

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 0cf2a26388e5..cf03c57d0feb 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -37,6 +37,31 @@
         } while (0)
 #endif
 
+#ifdef CONFIG_F2FS_FAULT_INJECTION
+enum {
+        FAULT_KMALLOC,
+        FAULT_MAX,
+};
+
+extern u32 f2fs_fault_rate;
+extern atomic_t f2fs_ops;
+extern char *fault_name[FAULT_MAX];
+
+static inline bool time_to_inject(int type)
+{
+        atomic_inc(&f2fs_ops);
+        if (f2fs_fault_rate && (atomic_read(&f2fs_ops) >= f2fs_fault_rate)) {
+                atomic_set(&f2fs_ops, 0);
+                printk("%sF2FS-fs : inject %s in %pF\n",
+                                KERN_INFO,
+                                fault_name[type],
+                                __builtin_return_address(0));
+                return true;
+        }
+        return false;
+}
+#endif
+
 /*
  * For mount options
  */
@@ -1647,6 +1672,10 @@ static inline bool f2fs_may_extent_tree(struct inode *inode)
 
 static inline void *f2fs_kmalloc(size_t size, gfp_t flags)
 {
+#ifdef CONFIG_F2FS_FAULT_INJECTION
+        if (time_to_inject(FAULT_KMALLOC))
+                return NULL;
+#endif
         return kmalloc(size, flags);
 }