+
+ /*
+ * __vmalloc() will allocate data pages and auxillary structures (e.g.
+ * pagetables) with GFP_KERNEL, yet we may be under GFP_NOFS context
+ * here. Hence we need to tell memory reclaim that we are in such a
+ * context via PF_MEMALLOC_NOIO to prevent memory reclaim re-entering
+ * the filesystem here and potentially deadlocking.
+ */
+ if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS))
+ noio_flag = memalloc_noio_save();
+
+ lflags = kmem_flags_convert(flags);
+ ptr = __vmalloc(size, lflags | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL);
+
+ if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS))
+ memalloc_noio_restore(noio_flag);
+
+ return ptr;