diff options
| -rw-r--r-- | sys/kern/uipc_mbuf.c | 40 | ||||
| -rw-r--r-- | sys/sys/mbuf.h | 9 |
2 files changed, 29 insertions, 20 deletions
diff --git a/sys/kern/uipc_mbuf.c b/sys/kern/uipc_mbuf.c index 8661509b9d8..22e131c9711 100644 --- a/sys/kern/uipc_mbuf.c +++ b/sys/kern/uipc_mbuf.c @@ -1,4 +1,4 @@ -/* $OpenBSD: uipc_mbuf.c,v 1.260 2018/11/09 14:14:31 claudio Exp $ */ +/* $OpenBSD: uipc_mbuf.c,v 1.261 2018/11/12 07:45:52 claudio Exp $ */ /* $NetBSD: uipc_mbuf.c,v 1.15.4.1 1996/06/13 17:11:44 cgd Exp $ */ /* @@ -150,6 +150,11 @@ struct pool_allocator m_pool_allocator = { static void (*mextfree_fns[4])(caddr_t, u_int, void *); static u_int num_extfree_fns; +#define M_DATABUF(m) ((m)->m_flags & M_EXT ? (m)->m_ext.ext_buf : \ + (m)->m_flags & M_PKTHDR ? (m)->m_pktdat : (m)->m_dat) +#define M_SIZE(m) ((m)->m_flags & M_EXT ? (m)->m_ext.ext_size : \ + (m)->m_flags & M_PKTHDR ? MHLEN : MLEN) + /* * Initialize the mbuf allocator. */ @@ -1262,14 +1267,7 @@ m_zero(struct mbuf *m) panic("m_zero: M_READONLY"); #endif /* DIAGNOSTIC */ - if (m->m_flags & M_EXT) - explicit_bzero(m->m_ext.ext_buf, m->m_ext.ext_size); - else { - if (m->m_flags & M_PKTHDR) - explicit_bzero(m->m_pktdat, MHLEN); - else - explicit_bzero(m->m_dat, MLEN); - } + explicit_bzero(M_DATABUF(m), M_SIZE(m)); } /* @@ -1321,9 +1319,8 @@ m_leadingspace(struct mbuf *m) { if (M_READONLY(m)) return 0; - return (m->m_flags & M_EXT ? m->m_data - m->m_ext.ext_buf : - m->m_flags & M_PKTHDR ? m->m_data - m->m_pktdat : - m->m_data - m->m_dat); + KASSERT(m->m_data >= M_DATABUF(m)); + return m->m_data - M_DATABUF(m); } /* @@ -1335,9 +1332,22 @@ m_trailingspace(struct mbuf *m) { if (M_READONLY(m)) return 0; - return (m->m_flags & M_EXT ? m->m_ext.ext_buf + - m->m_ext.ext_size - (m->m_data + m->m_len) : - &m->m_dat[MLEN] - (m->m_data + m->m_len)); + KASSERT(M_DATABUF(m) + M_SIZE(m) >= (m->m_data + m->m_len)); + return M_DATABUF(m) + M_SIZE(m) - (m->m_data + m->m_len); +} + +/* + * Set the m_data pointer of a newly-allocated mbuf to place an object of + * the specified size at the end of the mbuf, longword aligned. + */ +void +m_align(struct mbuf *m, int len) +{ + KASSERT(len >= 0 && !M_READONLY(m)); + KASSERT(m->m_data == M_DATABUF(m)); /* newly-allocated check */ + KASSERT(((len + sizeof(long) - 1) &~ (sizeof(long) - 1)) <= M_SIZE(m)); + + m->m_data = M_DATABUF(m) + ((M_SIZE(m) - (len)) &~ (sizeof(long) - 1)); } /* diff --git a/sys/sys/mbuf.h b/sys/sys/mbuf.h index 64ef9fab147..5135942bbfe 100644 --- a/sys/sys/mbuf.h +++ b/sys/sys/mbuf.h @@ -1,4 +1,4 @@ -/* $OpenBSD: mbuf.h,v 1.239 2018/11/09 14:14:32 claudio Exp $ */ +/* $OpenBSD: mbuf.h,v 1.240 2018/11/12 07:45:52 claudio Exp $ */ /* $NetBSD: mbuf.h,v 1.19 1996/02/09 18:25:14 christos Exp $ */ /* @@ -348,14 +348,12 @@ u_int mextfree_register(void (*)(caddr_t, u_int, void *)); * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place * an object of the specified size at the end of the mbuf, longword aligned. */ -#define M_ALIGN(m, len) \ - (m)->m_data += (MLEN - (len)) &~ (sizeof(long) - 1) +#define M_ALIGN(m, len) m_align((m), (len)) /* * As above, for mbufs allocated with m_gethdr/MGETHDR * or initialized by M_MOVE_PKTHDR. */ -#define MH_ALIGN(m, len) \ - (m)->m_data += (MHLEN - (len)) &~ (sizeof(long) - 1) +#define MH_ALIGN(m, len) m_align((m), (len)) /* * Determine if an mbuf's data area is read-only. This is true for @@ -441,6 +439,7 @@ struct mbuf *m_makespace(struct mbuf *, int, int, int *); struct mbuf *m_getptr(struct mbuf *, int, int *); int m_leadingspace(struct mbuf *); int m_trailingspace(struct mbuf *); +void m_align(struct mbuf *, int); struct mbuf *m_clget(struct mbuf *, int, u_int); void m_extref(struct mbuf *, struct mbuf *); void m_pool_init(struct pool *, u_int, u_int, const char *); |