From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.warmcat.com (mail.warmcat.com [163.172.24.82]) by dpdk.org (Postfix) with ESMTP id 982887F70 for ; Wed, 9 May 2018 03:50:35 +0200 (CEST) From: Andy Green To: dev@dpdk.org Date: Wed, 09 May 2018 09:31:05 +0800 Message-ID: <152582946580.6809.14461590402993659685.stgit@localhost.localdomain> In-Reply-To: <152582834896.6809.14521072557832633661.stgit@localhost.localdomain> References: <152582834896.6809.14521072557832633661.stgit@localhost.localdomain> User-Agent: StGit/unknown-version Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Subject: [dpdk-dev] [PATCH v2 03/18] drivers/bus/dpaa: fix inconsistent struct alignment X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 May 2018 01:50:35 -0000 The actual descriptor for qm_mr_entry is 64-byte aligned. But the original code plays a trick, and puts a u8 common to the three descriptor subtypes in the union afterwards outside their structure definitions. Unfortunately since they compose a struct qm_fd with alignment 8, this trick destroys the ability of the compiler to understand what has happened, resulting in this kind of problem: /home/agreen/projects/dpdk/drivers/bus/dpaa/include/ fsl_qman.h:354:3: error: alignment 1 of ‘struct ’ is less than 8 [-Werror=packed-not-aligned] } __packed dcern; on gcc 8 / Fedora 28 out of the box. This patch moves the u8 verb into the structure definitions composed into the union, so the alignment of the parent struct containing the alignment 8 object can also be seen to be alignment 8 by the compiler. Uses of .verb are fixed up to use .ern.verb (the same offset of +0 inside all the structs in the union). The final struct layout should be unchanged. Signed-off-by: Andy Green --- drivers/bus/dpaa/base/qbman/qman.c | 14 +++++++------- drivers/bus/dpaa/include/fsl_qman.h | 24 +++++++++++++----------- 2 files changed, 20 insertions(+), 18 deletions(-) diff --git a/drivers/bus/dpaa/base/qbman/qman.c b/drivers/bus/dpaa/base/qbman/qman.c index 2810fdd26..27d98cc10 100644 --- a/drivers/bus/dpaa/base/qbman/qman.c +++ b/drivers/bus/dpaa/base/qbman/qman.c @@ -314,9 +314,9 @@ static int drain_mr_fqrni(struct qm_portal *p) if (!msg) return 0; } - if ((msg->verb & QM_MR_VERB_TYPE_MASK) != QM_MR_VERB_FQRNI) { + if ((msg->ern.verb & QM_MR_VERB_TYPE_MASK) != QM_MR_VERB_FQRNI) { /* We aren't draining anything but FQRNIs */ - pr_err("Found verb 0x%x in MR\n", msg->verb); + pr_err("Found verb 0x%x in MR\n", msg->ern.verb); return -1; } qm_mr_next(p); @@ -483,7 +483,7 @@ static inline void qm_mr_pvb_update(struct qm_portal *portal) /* when accessing 'verb', use __raw_readb() to ensure that compiler * inlining doesn't try to optimise out "excess reads". */ - if ((__raw_readb(&res->verb) & QM_MR_VERB_VBIT) == mr->vbit) { + if ((__raw_readb(&res->ern.verb) & QM_MR_VERB_VBIT) == mr->vbit) { mr->pi = (mr->pi + 1) & (QM_MR_SIZE - 1); if (!mr->pi) mr->vbit ^= QM_MR_VERB_VBIT; @@ -832,7 +832,7 @@ static u32 __poll_portal_slow(struct qman_portal *p, u32 is) goto mr_done; swapped_msg = *msg; hw_fd_to_cpu(&swapped_msg.ern.fd); - verb = msg->verb & QM_MR_VERB_TYPE_MASK; + verb = msg->ern.verb & QM_MR_VERB_TYPE_MASK; /* The message is a software ERN iff the 0x20 bit is set */ if (verb & 0x20) { switch (verb) { @@ -1666,7 +1666,7 @@ int qman_retire_fq(struct qman_fq *fq, u32 *flags) */ struct qm_mr_entry msg; - msg.verb = QM_MR_VERB_FQRNI; + msg.ern.verb = QM_MR_VERB_FQRNI; msg.fq.fqs = mcr->alterfq.fqs; msg.fq.fqid = fq->fqid; #ifdef CONFIG_FSL_QMAN_FQ_LOOKUP @@ -2643,7 +2643,7 @@ int qman_shutdown_fq(u32 fqid) qm_mr_pvb_update(low_p); msg = qm_mr_current(low_p); while (msg) { - if ((msg->verb & + if ((msg->ern.verb & QM_MR_VERB_TYPE_MASK) == QM_MR_VERB_FQRN) found_fqrn = 1; @@ -2711,7 +2711,7 @@ int qman_shutdown_fq(u32 fqid) qm_mr_pvb_update(low_p); msg = qm_mr_current(low_p); while (msg) { - if ((msg->verb & QM_MR_VERB_TYPE_MASK) == + if ((msg->ern.verb & QM_MR_VERB_TYPE_MASK) == QM_MR_VERB_FQRL) orl_empty = 1; qm_mr_next(low_p); diff --git a/drivers/bus/dpaa/include/fsl_qman.h b/drivers/bus/dpaa/include/fsl_qman.h index e9793f30d..e4ad7ae48 100644 --- a/drivers/bus/dpaa/include/fsl_qman.h +++ b/drivers/bus/dpaa/include/fsl_qman.h @@ -284,20 +284,20 @@ static inline dma_addr_t qm_sg_addr(const struct qm_sg_entry *sg) } while (0) /* See 1.5.8.1: "Enqueue Command" */ -struct qm_eqcr_entry { +struct __rte_aligned(8) qm_eqcr_entry { u8 __dont_write_directly__verb; u8 dca; u16 seqnum; u32 orp; /* 24-bit */ u32 fqid; /* 24-bit */ u32 tag; - struct qm_fd fd; + struct qm_fd fd; /* this has alignment 8 */ u8 __reserved3[32]; } __packed; /* "Frame Dequeue Response" */ -struct qm_dqrr_entry { +struct __rte_aligned(8) qm_dqrr_entry { u8 verb; u8 stat; u16 seqnum; /* 15-bit */ @@ -305,7 +305,7 @@ struct qm_dqrr_entry { u8 __reserved2[3]; u32 fqid; /* 24-bit */ u32 contextB; - struct qm_fd fd; + struct qm_fd fd; /* this has alignment 8 */ u8 __reserved4[32]; }; @@ -323,18 +323,19 @@ struct qm_dqrr_entry { /* "ERN Message Response" */ /* "FQ State Change Notification" */ struct qm_mr_entry { - u8 verb; union { struct { + u8 verb; u8 dca; u16 seqnum; u8 rc; /* Rejection Code */ u32 orp:24; u32 fqid; /* 24-bit */ u32 tag; - struct qm_fd fd; - } __packed ern; + struct qm_fd fd; /* this has alignment 8 */ + } __packed __rte_aligned(8) ern; struct { + u8 verb; #if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ u8 colour:2; /* See QM_MR_DCERN_COLOUR_* */ u8 __reserved1:4; @@ -349,18 +350,19 @@ struct qm_mr_entry { u32 __reserved3:24; u32 fqid; /* 24-bit */ u32 tag; - struct qm_fd fd; - } __packed dcern; + struct qm_fd fd; /* this has alignment 8 */ + } __packed __rte_aligned(8) dcern; struct { + u8 verb; u8 fqs; /* Frame Queue Status */ u8 __reserved1[6]; u32 fqid; /* 24-bit */ u32 contextB; u8 __reserved2[16]; - } __packed fq; /* FQRN/FQRNI/FQRL/FQPN */ + } __packed __rte_aligned(8) fq; /* FQRN/FQRNI/FQRL/FQPN */ }; u8 __reserved2[32]; -} __packed; +} __packed __rte_aligned(8); #define QM_MR_VERB_VBIT 0x80 /* * ERNs originating from direct-connect portals ("dcern") use 0x20 as a verb