summaryrefslogtreecommitdiff
path: root/drivers/infiniband/hw/hfi1/user_sdma.h
AgeCommit message (Collapse)AuthorFilesLines
2018-12-21IB/hfi1: Remove race conditions in user_sdma send pathMichael J. Ruhl1-1/+6
commit 28a9a9e83ceae2cee25b9af9ad20d53aaa9ab951 upstream Packet queue state is over used to determine SDMA descriptor availablitity and packet queue request state. cpu 0 ret = user_sdma_send_pkts(req, pcount); cpu 0 if (atomic_read(&pq->n_reqs)) cpu 1 IRQ user_sdma_txreq_cb calls pq_update() (state to _INACTIVE) cpu 0 xchg(&pq->state, SDMA_PKT_Q_ACTIVE); At this point pq->n_reqs == 0 and pq->state is incorrectly SDMA_PKT_Q_ACTIVE. The close path will hang waiting for the state to return to _INACTIVE. This can also change the state from _DEFERRED to _ACTIVE. However, this is a mostly benign race. Remove the racy code path. Use n_reqs to determine if a packet queue is active or not. Cc: <stable@vger.kernel.org> # 4.9.0 Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com> Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2016-08-03IB/hfi1: Use evict mmu rb operationDean Luick1-3/+1
Use the new cache evict operation in the SDMA code. This allows the cache to properly coordinate evicts and removes, preventing any race. With this change, the separate list, lock, and race flag are not needed. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dean Luick <dean.luick@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-08-03IB/hfi1: Make the cache handler own its rb tree rootDean Luick1-1/+1
The objects which use cache handling should reference their own handler object not the internal data structure it uses to track the nodes. Have the "users" of the mmu notifier code pass opaque objects which can then be properly used in the mmu callbacks depending on the owners needs. This patch has the additional benefit that operations no longer require a look up in a list to find the handlers. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dean Luick <dean.luick@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-08-03IB/hfi1: Make use of mm consistentIra Weiny1-0/+1
The hfi1 driver registers a mmu_notifier callback when /dev/hfi1_* is opened, and unregisters it when the device is closed. The driver incorrectly assumes that the close will always happen from the same context as the open. In particular, closes due to SIGKILL or OOM killer activity may happen from a different context. In these cases, the wrong mm is passed to mmu_notifier_unregister(), which causes improper reference counting for the victim mm, and eventual memory corruption. Preserve the mm for all open file descriptors and use this mm rather than current->mm for memory operations for the lifetime of that fd. Note: this patch leaves 1 use of current->mm in place. This use is removed in a follow on patch because other functional changes were required prior to that use being removed. If registration fails, there is no reason to keep the handler object around. Free the handler object rather than add it to the list to prevent any mmu_notifier operations, including unregister, when registration fails. Suggested-by: Jim Foraker <foraker1@llnl.gov> Reviewed-by: Dean Luick <dean.luick@intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-08-03IB/hfi1: Fix user SDMA racy user request claimDean Luick1-0/+1
The user SDMA in-use claim bit is in the structure that gets zeroed out once the claim is made. Move the request in-use flag into its own bit array and use that for atomic claims. This cleans up the claim code and removes any race possibility. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dean Luick <dean.luick@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-05-26IB/hfi1: Move driver out of stagingDennis Dalessandro1-0/+84
The TODO list for the hfi1 driver was completed during 4.6. In addition other objections raised (which are far beyond what was in the TODO list) have been addressed as well. It is now time to remove the driver from staging and into the drivers/infiniband sub-tree. Reviewed-by: Jubin John <jubin.john@intel.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com>