From 53b8b3ffd5e0b10f3c683096a663d0cc22179c43 Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Thu, 7 Jul 2005 17:57:17 -0700 Subject: [PATCH] [PATCH] IB uverbs: add mthca mmap support Add support for mmap() method to mthca, so that userspace can get access to doorbell registers. This allows userspace to get direct access to the HCA for data path operations. Each userspace context gets its own copy of the doorbell registers and is only allowed to use resources that the kernel has given it access to. In other words, this is safe. Signed-off-by: Roland Dreier Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/infiniband/hw/mthca/mthca_provider.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/infiniband/hw/mthca/mthca_provider.c b/drivers/infiniband/hw/mthca/mthca_provider.c index bfd33a470020..9acb8c54ce4f 100644 --- a/drivers/infiniband/hw/mthca/mthca_provider.c +++ b/drivers/infiniband/hw/mthca/mthca_provider.c @@ -35,6 +35,7 @@ */ #include +#include #include "mthca_dev.h" #include "mthca_cmd.h" @@ -340,6 +341,22 @@ static int mthca_dealloc_ucontext(struct ib_ucontext *context) return 0; } +static int mthca_mmap_uar(struct ib_ucontext *context, + struct vm_area_struct *vma) +{ + if (vma->vm_end - vma->vm_start != PAGE_SIZE) + return -EINVAL; + + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + if (remap_pfn_range(vma, vma->vm_start, + to_mucontext(context)->uar.pfn, + PAGE_SIZE, vma->vm_page_prot)) + return -EAGAIN; + + return 0; +} + static struct ib_pd *mthca_alloc_pd(struct ib_device *ibdev, struct ib_ucontext *context, struct ib_udata *udata) @@ -766,6 +783,7 @@ int mthca_register_device(struct mthca_dev *dev) dev->ib_dev.query_gid = mthca_query_gid; dev->ib_dev.alloc_ucontext = mthca_alloc_ucontext; dev->ib_dev.dealloc_ucontext = mthca_dealloc_ucontext; + dev->ib_dev.mmap = mthca_mmap_uar; dev->ib_dev.alloc_pd = mthca_alloc_pd; dev->ib_dev.dealloc_pd = mthca_dealloc_pd; dev->ib_dev.create_ah = mthca_ah_create; -- 2.20.1