Re: [PATCH] staging: lustre: ko2iblnd: Adapt to the removal of ib_get_dma_mr()

From: James Simmons
Date: Sun Feb 19 2017 - 21:39:32 EST


> In Linux kernel 4.9-rc1, the function ib_get_dma_mr()
> was removed and a second parameter was added to ib_alloc_pd().
> As this broke the building of the ko2iblnd module in
> staging, the Kconfig for LNet has marked ko2iblnd as broken
> and stopped building it.
>
> This patch fixes this breakage by:
>
> - Removing the BROKEN tag from lnet/Kconfig.
> - Make it so the module parameter map_on_demand can no longer be
> zero (we have to configure FMR/FastReg pools; it can no longer be
> off).
> - No longer try to use the global DMA memory region, but make use
> of the FMR/FastReg pool for all RDMA Tx operations.
> - Everywhere we are using the device DMA mr to derive the
> L-key for non-registered memory regions, use the
> pd->local_dma_lkey value instead.
> - Make the default map_on_demand = 256. This will allow nodes with
> this patch to still connected to older nodes without this patch
> and FMR/FastReg turned off. When FMR/FastReg is turned off, we
> use 256 as the max frags so the two sides will still be able to
> communicate and work.
> - Fix a mistake with BUILD_BUG_ON calls in o2iblnd.c which caused
> compiling to fail.
>
> Signed-off-by: Doug Oucharek <doug.s.oucharek@xxxxxxxxx>
> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-9026
> Reviewed-on: https://review.whamcloud.com/#/c/24931/
> Reviewed-by: James Simmons <uja.ornl@xxxxxxxxx>

Reviewed-by: James Simmons <jsimmons@xxxxxxxxxxxxx>

> Changelog:
> v1) Initial patch
> v2) Rebased and handle a fix to BUILD_BUG_ON
> ---
> drivers/staging/lustre/lnet/Kconfig | 1 -
> .../staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c | 77 ++--------------------
> .../staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h | 3 -
> .../staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c | 17 +----
> .../lustre/lnet/klnds/o2iblnd/o2iblnd_modparams.c | 12 ++--
> 5 files changed, 16 insertions(+), 94 deletions(-)
>
> diff --git a/drivers/staging/lustre/lnet/Kconfig b/drivers/staging/lustre/lnet/Kconfig
> index 13b4327..2b59301 100644
> --- a/drivers/staging/lustre/lnet/Kconfig
> +++ b/drivers/staging/lustre/lnet/Kconfig
> @@ -35,7 +35,6 @@ config LNET_SELFTEST
> config LNET_XPRT_IB
> tristate "LNET infiniband support"
> depends on LNET && INFINIBAND && INFINIBAND_ADDR_TRANS
> - depends on BROKEN
> default LNET && INFINIBAND
> help
> This option allows the LNET users to use infiniband as an
> diff --git a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c
> index b1e8508..0618b79 100644
> --- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c
> +++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c
> @@ -1281,27 +1281,6 @@ static void kiblnd_map_tx_pool(struct kib_tx_pool *tpo)
> }
> }
>
> -struct ib_mr *kiblnd_find_rd_dma_mr(struct lnet_ni *ni, struct kib_rdma_desc *rd,
> - int negotiated_nfrags)
> -{
> - struct kib_net *net = ni->ni_data;
> - struct kib_hca_dev *hdev = net->ibn_dev->ibd_hdev;
> - struct lnet_ioctl_config_o2iblnd_tunables *tunables;
> - __u16 nfrags;
> - int mod;
> -
> - tunables = &ni->ni_lnd_tunables->lt_tun_u.lt_o2ib;
> - mod = tunables->lnd_map_on_demand;
> - nfrags = (negotiated_nfrags != -1) ? negotiated_nfrags : mod;
> -
> - LASSERT(hdev->ibh_mrs);
> -
> - if (mod > 0 && nfrags <= rd->rd_nfrags)
> - return NULL;
> -
> - return hdev->ibh_mrs;
> -}
> -
> static void kiblnd_destroy_fmr_pool(struct kib_fmr_pool *fpo)
> {
> LASSERT(!fpo->fpo_map_count);
> @@ -2168,21 +2147,12 @@ static int kiblnd_net_init_pools(struct kib_net *net, lnet_ni_t *ni, __u32 *cpts
> int ncpts)
> {
> struct lnet_ioctl_config_o2iblnd_tunables *tunables;
> - unsigned long flags;
> int cpt;
> int rc;
> int i;
>
> tunables = &ni->ni_lnd_tunables->lt_tun_u.lt_o2ib;
>
> - read_lock_irqsave(&kiblnd_data.kib_global_lock, flags);
> - if (!tunables->lnd_map_on_demand) {
> - read_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
> - goto create_tx_pool;
> - }
> -
> - read_unlock_irqrestore(&kiblnd_data.kib_global_lock, flags);
> -
> if (tunables->lnd_fmr_pool_size < *kiblnd_tunables.kib_ntx / 4) {
> CERROR("Can't set fmr pool size (%d) < ntx / 4(%d)\n",
> tunables->lnd_fmr_pool_size,
> @@ -2227,7 +2197,6 @@ static int kiblnd_net_init_pools(struct kib_net *net, lnet_ni_t *ni, __u32 *cpts
> if (i > 0)
> LASSERT(i == ncpts);
>
> - create_tx_pool:
> /*
> * cfs_precpt_alloc is creating an array of struct kib_tx_poolset
> * The number of struct kib_tx_poolsets create is equal to the
> @@ -2283,20 +2252,8 @@ static int kiblnd_hdev_get_attr(struct kib_hca_dev *hdev)
> return -EINVAL;
> }
>
> -static void kiblnd_hdev_cleanup_mrs(struct kib_hca_dev *hdev)
> -{
> - if (!hdev->ibh_mrs)
> - return;
> -
> - ib_dereg_mr(hdev->ibh_mrs);
> -
> - hdev->ibh_mrs = NULL;
> -}
> -
> void kiblnd_hdev_destroy(struct kib_hca_dev *hdev)
> {
> - kiblnd_hdev_cleanup_mrs(hdev);
> -
> if (hdev->ibh_pd)
> ib_dealloc_pd(hdev->ibh_pd);
>
> @@ -2306,28 +2263,6 @@ void kiblnd_hdev_destroy(struct kib_hca_dev *hdev)
> LIBCFS_FREE(hdev, sizeof(*hdev));
> }
>
> -static int kiblnd_hdev_setup_mrs(struct kib_hca_dev *hdev)
> -{
> - struct ib_mr *mr;
> - int rc;
> - int acflags = IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE;
> -
> - rc = kiblnd_hdev_get_attr(hdev);
> - if (rc)
> - return rc;
> -
> - mr = ib_get_dma_mr(hdev->ibh_pd, acflags);
> - if (IS_ERR(mr)) {
> - CERROR("Failed ib_get_dma_mr : %ld\n", PTR_ERR(mr));
> - kiblnd_hdev_cleanup_mrs(hdev);
> - return PTR_ERR(mr);
> - }
> -
> - hdev->ibh_mrs = mr;
> -
> - return 0;
> -}
> -
> /* DUMMY */
> static int kiblnd_dummy_callback(struct rdma_cm_id *cmid,
> struct rdma_cm_event *event)
> @@ -2482,9 +2417,9 @@ int kiblnd_dev_failover(struct kib_dev *dev)
> goto out;
> }
>
> - rc = kiblnd_hdev_setup_mrs(hdev);
> + rc = kiblnd_hdev_get_attr(hdev);
> if (rc) {
> - CERROR("Can't setup device: %d\n", rc);
> + CERROR("Can't get device attributes: %d\n", rc);
> goto out;
> }
>
> @@ -3021,12 +2956,12 @@ static void __exit ko2iblnd_exit(void)
> static int __init ko2iblnd_init(void)
> {
> BUILD_BUG_ON(sizeof(struct kib_msg) > IBLND_MSG_SIZE);
> - BUILD_BUG_ON(!offsetof(struct kib_msg,
> + BUILD_BUG_ON(offsetof(struct kib_msg,
> ibm_u.get.ibgm_rd.rd_frags[IBLND_MAX_RDMA_FRAGS])
> - <= IBLND_MSG_SIZE);
> - BUILD_BUG_ON(!offsetof(struct kib_msg,
> + > IBLND_MSG_SIZE);
> + BUILD_BUG_ON(offsetof(struct kib_msg,
> ibm_u.putack.ibpam_rd.rd_frags[IBLND_MAX_RDMA_FRAGS])
> - <= IBLND_MSG_SIZE);
> + > IBLND_MSG_SIZE);
>
> kiblnd_tunables_init();
>
> diff --git a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h
> index 2cb4298..366372d 100644
> --- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h
> +++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.h
> @@ -172,7 +172,6 @@ struct kib_hca_dev {
> __u64 ibh_page_mask; /* page mask of current HCA */
> int ibh_mr_shift; /* bits shift of max MR size */
> __u64 ibh_mr_size; /* size of MR */
> - struct ib_mr *ibh_mrs; /* global MR */
> struct ib_pd *ibh_pd; /* PD */
> struct kib_dev *ibh_dev; /* owner */
> atomic_t ibh_ref; /* refcount */
> @@ -978,8 +977,6 @@ static inline unsigned int kiblnd_sg_dma_len(struct ib_device *dev,
> #define KIBLND_CONN_PARAM(e) ((e)->param.conn.private_data)
> #define KIBLND_CONN_PARAM_LEN(e) ((e)->param.conn.private_data_len)
>
> -struct ib_mr *kiblnd_find_rd_dma_mr(struct lnet_ni *ni, struct kib_rdma_desc *rd,
> - int negotiated_nfrags);
> void kiblnd_map_rx_descs(struct kib_conn *conn);
> void kiblnd_unmap_rx_descs(struct kib_conn *conn);
> void kiblnd_pool_free_node(struct kib_pool *pool, struct list_head *node);
> diff --git a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c
> index e2f3f72..6eaa548 100644
> --- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c
> +++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c
> @@ -157,7 +157,6 @@ static int kiblnd_init_rdma(struct kib_conn *conn, struct kib_tx *tx, int type,
> struct kib_conn *conn = rx->rx_conn;
> struct kib_net *net = conn->ibc_peer->ibp_ni->ni_data;
> struct ib_recv_wr *bad_wrq = NULL;
> - struct ib_mr *mr = conn->ibc_hdev->ibh_mrs;
> int rc;
>
> LASSERT(net);
> @@ -165,9 +164,8 @@ static int kiblnd_init_rdma(struct kib_conn *conn, struct kib_tx *tx, int type,
> LASSERT(credit == IBLND_POSTRX_NO_CREDIT ||
> credit == IBLND_POSTRX_PEER_CREDIT ||
> credit == IBLND_POSTRX_RSRVD_CREDIT);
> - LASSERT(mr);
>
> - rx->rx_sge.lkey = mr->lkey;
> + rx->rx_sge.lkey = conn->ibc_hdev->ibh_pd->local_dma_lkey;
> rx->rx_sge.addr = rx->rx_msgaddr;
> rx->rx_sge.length = IBLND_MSG_SIZE;
>
> @@ -613,7 +611,6 @@ static int kiblnd_map_tx(lnet_ni_t *ni, struct kib_tx *tx, struct kib_rdma_desc
> {
> struct kib_net *net = ni->ni_data;
> struct kib_hca_dev *hdev = net->ibn_dev->ibd_hdev;
> - struct ib_mr *mr = NULL;
> __u32 nob;
> int i;
>
> @@ -635,14 +632,6 @@ static int kiblnd_map_tx(lnet_ni_t *ni, struct kib_tx *tx, struct kib_rdma_desc
> nob += rd->rd_frags[i].rf_nob;
> }
>
> - mr = kiblnd_find_rd_dma_mr(ni, rd, tx->tx_conn ?
> - tx->tx_conn->ibc_max_frags : -1);
> - if (mr) {
> - /* found pre-mapping MR */
> - rd->rd_key = (rd != tx->tx_rd) ? mr->rkey : mr->lkey;
> - return 0;
> - }
> -
> if (net->ibn_fmr_ps)
> return kiblnd_fmr_map_tx(net, tx, rd, nob);
>
> @@ -1028,16 +1017,14 @@ static int kiblnd_map_tx(lnet_ni_t *ni, struct kib_tx *tx, struct kib_rdma_desc
> struct ib_sge *sge = &tx->tx_sge[tx->tx_nwrq];
> struct ib_rdma_wr *wrq = &tx->tx_wrq[tx->tx_nwrq];
> int nob = offsetof(struct kib_msg, ibm_u) + body_nob;
> - struct ib_mr *mr = hdev->ibh_mrs;
>
> LASSERT(tx->tx_nwrq >= 0);
> LASSERT(tx->tx_nwrq < IBLND_MAX_RDMA_FRAGS + 1);
> LASSERT(nob <= IBLND_MSG_SIZE);
> - LASSERT(mr);
>
> kiblnd_init_msg(tx->tx_msg, type, body_nob);
>
> - sge->lkey = mr->lkey;
> + sge->lkey = hdev->ibh_pd->local_dma_lkey;
> sge->addr = tx->tx_msgaddr;
> sge->length = nob;
>
> diff --git a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_modparams.c b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_modparams.c
> index 44e960f..3c81b527 100644
> --- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_modparams.c
> +++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_modparams.c
> @@ -106,7 +106,8 @@
> module_param(concurrent_sends, int, 0444);
> MODULE_PARM_DESC(concurrent_sends, "send work-queue sizing");
>
> -static int map_on_demand;
> +#define IBLND_DEFAULT_MAP_ON_DEMAND IBLND_MAX_RDMA_FRAGS
> +static int map_on_demand = IBLND_DEFAULT_MAP_ON_DEMAND;
> module_param(map_on_demand, int, 0444);
> MODULE_PARM_DESC(map_on_demand, "map on demand");
>
> @@ -228,10 +229,13 @@ int kiblnd_tunables_setup(struct lnet_ni *ni)
> if (tunables->lnd_peercredits_hiw >= ni->ni_peertxcredits)
> tunables->lnd_peercredits_hiw = ni->ni_peertxcredits - 1;
>
> - if (tunables->lnd_map_on_demand < 0 ||
> + if (tunables->lnd_map_on_demand <= 0 ||
> tunables->lnd_map_on_demand > IBLND_MAX_RDMA_FRAGS) {
> - /* disable map-on-demand */
> - tunables->lnd_map_on_demand = 0;
> + /* Use the default */
> + CWARN("Invalid map_on_demand (%d), expects 1 - %d. Using default of %d\n",
> + tunables->lnd_map_on_demand,
> + IBLND_MAX_RDMA_FRAGS, IBLND_DEFAULT_MAP_ON_DEMAND);
> + tunables->lnd_map_on_demand = IBLND_DEFAULT_MAP_ON_DEMAND;
> }
>
> if (tunables->lnd_map_on_demand == 1) {
> --
> 1.8.3.1
>
>