[程序员] Linux错误码,一码多义?

/* * Allocate a region of KVA of the specified size and alignment, within the * vstart and vend. */static struct vmap_area *alloc_vmap_area(unsigned long size,unsigned long align,unsigned long vstart, unsigned long vend,int node, gfp_t gfp_mask){struct vmap_area *va;......if (unlikely(!vmap_initialized))return ERR_PTR(-EBUSY);