From 96249d70dd70496084c7ec1465ec449cd032955a Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Wed, 5 Aug 2015 14:14:45 -0600 Subject: [PATCH] IB/core: Guarantee that a local_dma_lkey is available Every single ULP requires a local_dma_lkey to do anything with a QP, so let us ensure one exists for every PD created. If the driver can supply a global local_dma_lkey then use that, otherwise ask the driver to create a local use all physical memory MR associated with the new PD. Signed-off-by: Jason Gunthorpe Reviewed-by: Sagi Grimberg Acked-by: Christoph Hellwig Reviewed-by: Steve Wise Reviewed-by: Ira Weiny Tested-by: Ira Weiny Signed-off-by: Doug Ledford --- drivers/infiniband/core/uverbs_cmd.c | 1 + drivers/infiniband/core/verbs.c | 47 +++++++++++++++++++++++++--- include/rdma/ib_verbs.h | 9 ++---- 3 files changed, 45 insertions(+), 12 deletions(-) diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c index bbb02ffe87df..258485ee46b2 100644 --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -562,6 +562,7 @@ ssize_t ib_uverbs_alloc_pd(struct ib_uverbs_file *file, pd->device = file->device->ib_dev; pd->uobject = uobj; + pd->local_mr = NULL; atomic_set(&pd->usecnt, 0); uobj->object = pd; diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c index c80ed1737666..2e5fd89a8929 100644 --- a/drivers/infiniband/core/verbs.c +++ b/drivers/infiniband/core/verbs.c @@ -213,24 +213,61 @@ EXPORT_SYMBOL(rdma_port_get_link_layer); /* Protection domains */ +/** + * ib_alloc_pd - Allocates an unused protection domain. + * @device: The device on which to allocate the protection domain. + * + * A protection domain object provides an association between QPs, shared + * receive queues, address handles, memory regions, and memory windows. + * + * Every PD has a local_dma_lkey which can be used as the lkey value for local + * memory operations. + */ struct ib_pd *ib_alloc_pd(struct ib_device *device) { struct ib_pd *pd; + struct ib_device_attr devattr; + int rc; + + rc = ib_query_device(device, &devattr); + if (rc) + return ERR_PTR(rc); pd = device->alloc_pd(device, NULL, NULL); + if (IS_ERR(pd)) + return pd; + + pd->device = device; + pd->uobject = NULL; + pd->local_mr = NULL; + atomic_set(&pd->usecnt, 0); + + if (devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY) + pd->local_dma_lkey = device->local_dma_lkey; + else { + struct ib_mr *mr; + + mr = ib_get_dma_mr(pd, IB_ACCESS_LOCAL_WRITE); + if (IS_ERR(mr)) { + ib_dealloc_pd(pd); + return (struct ib_pd *)mr; + } - if (!IS_ERR(pd)) { - pd->device = device; - pd->uobject = NULL; - atomic_set(&pd->usecnt, 0); + pd->local_mr = mr; + pd->local_dma_lkey = pd->local_mr->lkey; } - return pd; } EXPORT_SYMBOL(ib_alloc_pd); int ib_dealloc_pd(struct ib_pd *pd) { + if (pd->local_mr) { + if (ib_dereg_mr(pd->local_mr)) + return -EBUSY; + pd->local_mr = NULL; + } + if (atomic_read(&pd->usecnt)) return -EBUSY; diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index 5eff55c8b39d..09400512d579 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -1257,9 +1257,11 @@ struct ib_udata { }; struct ib_pd { + u32 local_dma_lkey; struct ib_device *device; struct ib_uobject *uobject; atomic_t usecnt; /* count all resources */ + struct ib_mr *local_mr; }; struct ib_xrcd { @@ -2192,13 +2194,6 @@ int ib_find_gid(struct ib_device *device, union ib_gid *gid, int ib_find_pkey(struct ib_device *device, u8 port_num, u16 pkey, u16 *index); -/** - * ib_alloc_pd - Allocates an unused protection domain. - * @device: The device on which to allocate the protection domain. - * - * A protection domain object provides an association between QPs, shared - * receive queues, address handles, memory regions, and memory windows. - */ struct ib_pd *ib_alloc_pd(struct ib_device *device); /** -- 2.20.1