From 9c6e6a80ee741adf6cb3cfd8eef7d1554f91fceb Mon Sep 17 00:00:00 2001 From: lic121 Date: Tue, 1 Mar 2022 13:26:23 +0000 Subject: [PATCH] libbpf: Unmap rings when umem deleted xsk_umem__create() does mmap for fill/comp rings, but xsk_umem__delete() doesn't do the unmap. This works fine for regular cases, because xsk_socket__delete() does unmap for the rings. But for the case that xsk_socket__create_shared() fails, umem rings are not unmapped. fill_save/comp_save are checked to determine if rings have already be unmapped by xsk. If fill_save and comp_save are NULL, it means that the rings have already been used by xsk. Then they are supposed to be unmapped by xsk_socket__delete(). Otherwise, xsk_umem__delete() does the unmap. Fixes: 2f6324a3937f ("libbpf: Support shared umems between queues and devices") Signed-off-by: Cheng Li Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220301132623.GA19995@vscode.7~ --- tools/lib/bpf/xsk.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c index edafe56..32a2f57 100644 --- a/tools/lib/bpf/xsk.c +++ b/tools/lib/bpf/xsk.c @@ -1193,12 +1193,23 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname, int xsk_umem__delete(struct xsk_umem *umem) { + struct xdp_mmap_offsets off; + int err; + if (!umem) return 0; if (umem->refcount) return -EBUSY; + err = xsk_get_mmap_offsets(umem->fd, &off); + if (!err && umem->fill_save && umem->comp_save) { + munmap(umem->fill_save->ring - off.fr.desc, + off.fr.desc + umem->config.fill_size * sizeof(__u64)); + munmap(umem->comp_save->ring - off.cr.desc, + off.cr.desc + umem->config.comp_size * sizeof(__u64)); + } + close(umem->fd); free(umem); -- 2.7.4