diff options
| -rw-r--r-- | mm/vmalloc.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 5dcb65dd9bf3..3824dc16ce1c 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -787,6 +787,28 @@ unsigned long vmalloc_nr_pages(void) return atomic_long_read(&nr_vmalloc_pages); } +static struct vmap_area *find_vmap_area_exceed_addr(unsigned long addr) +{ + struct vmap_area *va = NULL; + struct rb_node *n = vmap_area_root.rb_node; + + while (n) { + struct vmap_area *tmp; + + tmp = rb_entry(n, struct vmap_area, rb_node); + if (tmp->va_end > addr) { + va = tmp; + if (tmp->va_start <= addr) + break; + + n = n->rb_left; + } else + n = n->rb_right; + } + + return va; +} + static struct vmap_area *__find_vmap_area(unsigned long addr) { struct rb_node *n = vmap_area_root.rb_node; @@ -3287,9 +3309,14 @@ long vread(char *buf, char *addr, unsigned long count) count = -(unsigned long) addr; spin_lock(&vmap_area_lock); - va = __find_vmap_area((unsigned long)addr); + va = find_vmap_area_exceed_addr((unsigned long)addr); if (!va) goto finished; + + /* no intersects with alive vmap_area */ + if ((unsigned long)addr + count <= va->va_start) + goto finished; + list_for_each_entry_from(va, &vmap_area_list, list) { if (!count) break; |