From da57db25677f8566a354b0d0e4973a0fdcabcf84 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Wed, 8 Jan 2020 20:05:33 +0200 Subject: RDMA/core: Remove ucontext_lock from the uverbs_destry_ufile_hw() path This lock only serializes ucontext creation. Instead of checking the ucontext_lock during destruction hold the existing hw_destroy_rwsem during creation, which is the standard pattern for object creation. The simplification of locking is needed for the next patch. Link: https://lore.kernel.org/r/1578506740-22188-4-git-send-email-yishaih@mellanox.com Signed-off-by: Yishai Hadas Signed-off-by: Jason Gunthorpe --- drivers/infiniband/core/rdma_core.c | 21 +-------------------- drivers/infiniband/core/uverbs_cmd.c | 5 ++++- 2 files changed, 5 insertions(+), 21 deletions(-) (limited to 'drivers/infiniband/core') diff --git a/drivers/infiniband/core/rdma_core.c b/drivers/infiniband/core/rdma_core.c index 50251da123f7..5128cb16bb48 100644 --- a/drivers/infiniband/core/rdma_core.c +++ b/drivers/infiniband/core/rdma_core.c @@ -845,9 +845,7 @@ static int __uverbs_cleanup_ufile(struct ib_uverbs_file *ufile, } /* - * Destroy the uncontext and every uobject associated with it. If called with - * reason != RDMA_REMOVE_CLOSE this will not return until the destruction has - * been completed and ufile->ucontext is NULL. + * Destroy the uncontext and every uobject associated with it. * * This is internally locked and can be called in parallel from multiple * contexts. @@ -855,22 +853,6 @@ static int __uverbs_cleanup_ufile(struct ib_uverbs_file *ufile, void uverbs_destroy_ufile_hw(struct ib_uverbs_file *ufile, enum rdma_remove_reason reason) { - if (reason == RDMA_REMOVE_CLOSE) { - /* - * During destruction we might trigger something that - * synchronously calls release on any file descriptor. For - * this reason all paths that come from file_operations - * release must use try_lock. They can progress knowing that - * there is an ongoing uverbs_destroy_ufile_hw that will clean - * up the driver resources. - */ - if (!mutex_trylock(&ufile->ucontext_lock)) - return; - - } else { - mutex_lock(&ufile->ucontext_lock); - } - down_write(&ufile->hw_destroy_rwsem); /* @@ -899,7 +881,6 @@ void uverbs_destroy_ufile_hw(struct ib_uverbs_file *ufile, done: up_write(&ufile->hw_destroy_rwsem); - mutex_unlock(&ufile->ucontext_lock); } const struct uverbs_obj_type_class uverbs_fd_class = { diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c index 29b1b5ad8836..d71ffe44b8ae 100644 --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -218,6 +218,8 @@ static int ib_uverbs_get_context(struct uverbs_attr_bundle *attrs) if (ret) return ret; + if (!down_read_trylock(&file->hw_destroy_rwsem)) + return -EIO; mutex_lock(&file->ucontext_lock); ib_dev = srcu_dereference(file->device->ib_dev, &file->device->disassociate_srcu); @@ -284,7 +286,7 @@ static int ib_uverbs_get_context(struct uverbs_attr_bundle *attrs) smp_store_release(&file->ucontext, ucontext); mutex_unlock(&file->ucontext_lock); - + up_read(&file->hw_destroy_rwsem); return 0; err_uobj: @@ -298,6 +300,7 @@ err_alloc: err: mutex_unlock(&file->ucontext_lock); + up_read(&file->hw_destroy_rwsem); return ret; } -- cgit v1.2.3-59-g8ed1b