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path: root/drivers/ntb/ntb_transport.c
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2017-08-30ntb: transport shouldn't disable link due to bogus values in SPADsDave Jiang
commit f3fd2afed8eee91620d05b69ab94c14793c849d7 upstream. It seems that under certain scenarios the SPAD can have bogus values caused by an agent (i.e. BIOS or other software) that is not the kernel driver, and that causes memory window setup failure. This should not cause the link to be disabled because if we do that, the driver will never recover again. We have verified in testing that this issue happens and prevents proper link recovery. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by: Jon Mason <jdmason@kudzu.us> Fixes: 84f766855f61 ("ntb: stop link work when we do not have memory") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-30ntb: no sleep in ntb_async_tx_submitAllen Hubbe
commit 88931ec3dc11e7dbceb3b0df455693873b508fbe upstream. Do not sleep in ntb_async_tx_submit, which could deadlock. This reverts commit "8c874cc140d667f84ae4642bb5b5e0d6396d2ca4" Fixes: 8c874cc140d6 ("NTB: Address out of DMA descriptor issue with NTB") Reported-by: Jia-Ju Bai <baijiaju1990@163.com> Signed-off-by: Allen Hubbe <Allen.Hubbe@dell.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-30ntb_transport: fix bug calculating num_qps_mwLogan Gunthorpe
commit 8e8496e0e9564b66165f5219a4e8ed20b0d3fc6b upstream. A divide by zero error occurs if qp_count is less than mw_count because num_qps_mw is calculated to be zero. The calculation appears to be incorrect. The requirement is for num_qps_mw to be set to qp_count / mw_count with any remainder divided among the earlier mws. For example, if mw_count is 5 and qp_count is 12 then mws 0 and 1 will have 3 qps per window and mws 2 through 4 will have 2 qps per window. Thus, when mw_num < qp_count % mw_count, num_qps_mw is 1 higher than when mw_num >= qp_count. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Fixes: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers") Acked-by: Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-30ntb_transport: fix qp count bugLogan Gunthorpe
commit cb827ee6ccc3e480f0d9c0e8e53eef55be5b0414 upstream. In cases where there are more mw's than spads/2-2, the mw count gets reduced to match the limitation. ntb_transport also tries to ensure that there are fewer qps than mws but uses the full mw count instead of the reduced one. When this happens, the math in 'ntb_transport_setup_qp_mw' will get confused and result in a kernel paging request bug. This patch fixes the bug by reducing qp_count to the reduced mw count instead of the full mw count. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Fixes: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers") Acked-by: Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-23ntb_transport: Pick an unused queueThomas VanSelus
commit 8fcd0950c021d7be8493280541332b924b9de962 upstream. Fix typo causing ntb_transport_create_queue to select the first queue every time, instead of using the next free queue. Signed-off-by: Thomas VanSelus <tvanselus@xes-inc.com> Signed-off-by: Aaron Sierra <asierra@xes-inc.com> Acked-by: Allen Hubbe <Allen.Hubbe@dell.com> Fixes: fce8a7bb5 ("PCI-Express Non-Transparent Bridge Support") Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-23NTB: ntb_transport: fix debugfs_remove_recursiveAllen Hubbe
commit dd62245e73de9138333cb0e7a42c8bc1215c3ce6 upstream. The call to debugfs_remove_recursive(qp->debugfs_dir) of the sub-level directory must not be later than debugfs_remove_recursive(nt_debugfs_dir) of the top-level directory. Otherwise, the sub-level directory will not exist, and it would be invalid (panic) to attempt to remove it. This removes the top-level directory last, after sub-level directories have been cleaned up. Signed-off-by: Allen Hubbe <Allen.Hubbe@dell.com> Fixes: e26a5843f ("NTB: Split ntb_hw_intel and ntb_transport drivers") Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-13ntb_transport: make DMA_OUT_RESOURCE_TO HZ independentNicholas Mc Guire
schedule_timeout_* takes a timeout in jiffies but the code currently is passing in a constant which makes this timeout HZ dependent, so pass it through msecs_to_jiffies() to fix this up. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-08ntb: add DMA error handling for RX DMADave Jiang
Adding support on the rx DMA path to allow recovery of errors when DMA responds with error status and abort all the subsequent ops. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Cc: Jon Mason <jdmason@kudzu.us> Cc: linux-ntb@googlegroups.com Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-08-08ntb: add DMA error handling for TX DMADave Jiang
Adding support on the tx DMA path to allow recovery of errors when DMA responds with error status and abort all the subsequent ops. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Cc: Jon Mason <jdmason@kudzu.us> Cc: linux-ntb@googlegroups.com Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-08-05ntb_transport: Check the number of spads the hardware supportsLogan Gunthorpe
I'm working on hardware that currently has a limited number of scratchpad registers and ntb_ndev fails with no clue as to why. I feel it is better to fail early and provide a reasonable error message then to fail later on. The same is done to ntb_perf, but it doesn't currently require enough spads to actually fail. I've also removed the unused SPAD_MSG and SPAD_ACK enums so that MAX_SPAD accurately reflects the number of spads used. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05NTB: allocate number transport entries depending on size of ring sizeDave Jiang
Currently we only allocate a fixed default number of descriptors for the tx and rx side. We should dynamically resize it to the number of descriptors resides in the transport rings. We should know the number of transmit descriptors at initializaiton. We will allocate the default number of descriptors for receive side and allocate additional ones when we know the actual max entries for receive. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <allen.hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-18ntb: stop link work when we do not have memoryDave Jiang
Instead of keep trying to go through the init routine when we aren't able to allocate memory, we should just stop and go down. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-18ntb: stop tasklet from spinning forever during shutdown.Dave Jiang
We can leave tasklet spinning forever if we disable the tasklet during qp shutdown and the tasklets are still being kicked off. This hopefully should avoid that race condition. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reported-by: Alex Depoutovitch <alex@pernixdata.com> Tested-by: Alex Depoutovitch <alex@pernixdata.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-01-11NTB: Address out of DMA descriptor issue with NTBDave Jiang
The transport right now does not handle the case where we run out of DMA descriptors. We just fail when we do not succeed. Adding code to retry for a bit attempting to use the DMA engine instead of instantly fail to CPU copy. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-01-11NTB: ntb_process_tx error path bugJon Mason
The transmit overrun avoidance error path in ntb_process_tx accidentally swapped the first two values being passed to the tx_handler client. This could result in crashes in the ntb_netdev (or other out-of-tree NTB clients). Reported-by: Alex Depoutovitch <alex@pernixdata.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: fix 32-bit compiler warningArnd Bergmann
resource_size_t may be 32-bit wide on some architectures, which causes this warning when building the NTB code: drivers/ntb/ntb_transport.c: In function 'ntb_transport_link_work': drivers/ntb/ntb_transport.c:828:46: warning: right shift count >= width of type [-Wshift-count-overflow] The warning is harmless but can be avoided by using the upper_32_bits() macro. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers") Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: invalid buf pointer in multi-MW setupsJon Mason
Order of operations issue with the QP Num and MW count, which would result in the receive buffer pointer being invalid if there are more than 1 MW. Corrected with parenthesis to enforce the proper order of operations. Reported-by: John I. Kading <John.Kading@gd-ms.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: remove unused variableSudip Mukherjee
These variables were not used anywhere. So remove them. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: fix access of free-ed pointerSudip Mukherjee
We were accessing nt->mw_vec after freeing it. Fix the error path so that we free nt->mw_vec after we have finished using it. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: Fix issue where we may be accessing NULL ptrDave Jiang
smatch detected an issue in the function ntb_transport_max_size() where we could be dereferencing a dma channel pointer when it is NULL. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Use unique DMA channels for TX and RXDave Jiang
Allocate two DMA channels, one for TX operation and one for RX operation, instead of having one DMA channel for everything. This provides slightly better performance, and also will make error handling cleaner later on. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Remove dma_sync_wait from ntb_async_rxAllen Hubbe
The dma_sync_wait can hurt the performance of workloads mixed with both large and small frames. Large frames will be copied using the dma engine. Small frames will be copied by the cpu. The dma_sync_wait prevents the cpu and dma engine copying in parallel. In the period where the cpu is copying, the dma engine is stopped. The dma engine is not doing any useful work to copy large frames during that time, and the additional time to restart the dma engine for the next large frame. This will decrease the throughput for the portion of a workload with large frames. In the period where the dma engine is copying, the cpu is held up waiting for dma to complete. The small frames processing will be delayed until the dma is complete. The RX frames are completed in-order, and the processing of small frames takes very little time, so dma_sync_wait may have an insignificant impact on the respose time of frames. The more significant impact is to the system, because the delay in dma_sync_wait is implemented as busy non-blocking wait. This can prevent the delayed core from doing any useful work, even if it could be processing work for other drivers, unrelated to transport RX processing. After applying the earlier patch to fix out-of-order RX acknoledgement, the dma_sync_wait is no longer necessary. Remove it, so that cpu memcpy will proceed immediately for small frames, in parallel with ongoing dma for large frames. Do not hold up the cpu from doing work while dma is in progress. The prior fix will continue to ensure in-order completion of the RX frames to the upper layer, and in-order delivery of the RX acknoledgement. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Clean up QP stats infoDave Jiang
Make QP stats info more readable for debugging purposes. Also add an entry to indicate whether DMA is being used. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Make the transport list in order of discoveryDave Jiang
The list should be added from the bottom and not the top in order to ensure the transport is provided in the same order to clients as ntb devices are discovered. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Add flow control to the ntb_netdevDave Jiang
Right now if we push the NTB really hard, we start dropping packets due to not able to process the packets fast enough. We need to st:qop the upper layer from flooding us when that happens. A timer is necessary in order to restart the queue once the resource has been processed on the receive side. Due to the way NTB is setup, the resources on the tx side are tied to the processing of the rx side and there's no async way to know when the rx side has released those resources. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-08-09NTB: Fix dereference before checkAllen Hubbe
Remove early dereference of a pointer that is checked later in the code. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-08-09NTB: Fix zero size or integer overflow in ntb_set_mwAllen Hubbe
A plain 32 bit integer will overflow for values over 4GiB. Change the plain integer size to the appropriate size type in ntb_set_mw. Change the type of the size parameter and two local variables used for size. Even if there is no overflow, a size of zero is invalid here. Reported-by: Juyoung Jung <jjung@micron.com> Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-08-09NTB: Schedule to receive on QP link upAllen Hubbe
Schedule to receive on QP link up, to make sure that the doorbell is properly cleared for interrupts. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-08-09NTB: Fix oops in debugfs when transport is half-upDave Jiang
When the remote side is not up, we do not have all the context for the transport, and that causes NULL ptr access. Have the debugfs reads check to see if transport is up before we make access. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-08-09NTB: Fix transport stats for multiple devicesDave Jiang
Currently the debugfs does not have files for all NTB transport queue pairs. When there are multiple NTBs present in a system, the QP names of the last transport clobber the names of previously added transport QPs. Only the last added QPs can be observed via debugfs. Create a directory per NTB transport to associate the QPs with that transport. Name the directory the same as the PCI device. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-08-09NTB: Fix ntb_transport out-of-order RX updateAllen Hubbe
It was possible for a synchronous update of the RX index in the error case to get ahead of the asynchronous RX index update in the normal case. Change the RX processing to preserve an RX completion order. There were two error cases. First, if a buffer is not present to receive data, there would be no queue entry to preserve the RX completion order. Instead of dropping the RX frame, leave the RX frame in the ring. Schedule RX processing when RX entries are enqueued, in case there are RX frames waiting in the ring to be received. Second, if a buffer is too small to receive data, drop the frame in the ring, mark the RX entry as done, and indicate the error in the RX entry length. Check for a negative length in the receive callback in ntb_netdev, and count occurrences as rx_length_errors. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Print driver name and version in module initDave Jiang
Printouts driver name and version to indicate what is being loaded. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Increase transport MTU to 64k from 16kDave Jiang
Benchmarking showed a significant performance increase with the MTU size to 64k instead of 16k. Change the driver default to 64k. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Default to CPU memcpy for performanceDave Jiang
Disable DMA usage by default, since the CPU provides much better performance with write combining. Provide a module parameter to enable DMA usage when offloading the memcpy is preferred. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Improve performance with write combiningDave Jiang
Changing the memory window BAR mappings to write combining significantly boosts the performance. We will also use memcpy that uses non-temporal store, which showed performance improvement when doing non-cached memcpys. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Use NUMA memory and DMA chan in transportAllen Hubbe
Allocate memory and request the DMA channel for the same NUMA node as the NTB device. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Rate limit ntb_qp_link_workAllen Hubbe
When the ntb transport is connecting and waiting for the peer, the debug console receives lots of debug level messages about the remote qp link status being down. Rate limit those messages. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Reset transport QP link stats on downAllen Hubbe
Reset the link stats when the link goes down. In particular, the TX and RX index and count must be reset, or else the TX side will be sending packets to the RX side where the RX side is not expecting them. Reset all the stats, to be consistent. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Do not advance transport RX on link downAllen Hubbe
On link down, don't advance RX index to the next entry. The next entry should never be valid after receiving the link down flag. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Differentiate transport link down messagesAllen Hubbe
The same message "qp %d: Link Down\n" was printed at two locations in ntb_transport. Change the messages so they are distinct. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Read peer info from local SPAD in transportDave Jiang
The transport was writing and then reading the peer scratch pad, essentially reading what it just wrote instead of exchanging any information with the peer. The transport expects the peer values to be the same as the local values, so this issue was not obvious. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04NTB: Split ntb_hw_intel and ntb_transport driversAllen Hubbe
Change ntb_hw_intel to use the new NTB hardware abstraction layer. Split ntb_transport into its own driver. Change it to use the new NTB hardware abstraction layer. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-02NTB: Move files in preparation for NTB abstractionAllen Hubbe
This patch only moves files to their new locations, before applying the next two patches adding the NTB Abstraction layer. Splitting this patch from the next is intended make distinct which code is changed only due to moving the files, versus which are substantial code changes in adding the NTB Abstraction layer. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2014-09-14ntb: Add alignment check to meet hardware requirementDave Jiang
The NTB translate register must have the value to be BAR size aligned. This alignment check make sure that the DMA memory allocated has the proper alignment. Another requirement for NTB to function properly with memory window BAR size greater or equal to 4M is to use the CMA feature in 3.16 kernel with the appropriate CONFIG_CMA_ALIGNMENT and CONFIG_CMA_SIZE_MBYTES set. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2014-09-14NTB: correct the spread of queues over mw'sJon Mason
The detection of an uneven number of queues on the given memory windows was not correct. The mw_num is zero based and the mod should be division to spread them evenly over the mw's. Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07NTB: Code Style Clean-upJon Mason
Some white space and 80 char overruns corrected. Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07NTB: client event cleanupJon Mason
Provide a better event interface between the client and transport Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-26Merge tag 'ntb-3.13' of git://github.com/jonmason/ntbLinus Torvalds
Pull non-transparent bridge updates from Jon Mason: "NTB driver bug fixes to address a missed call to pci_enable_msix, NTB-RP Link Up issue, Xeon Doorbell errata workaround, ntb_transport link down race, and correct dmaengine_get/put usage. Also, clean-ups to remove duplicate defines and document a hardware errata. Finally, some changes to improve performance" * tag 'ntb-3.13' of git://github.com/jonmason/ntb: NTB: Disable interrupts and poll under high load NTB: Enable Snoop on Primary Side NTB: Document HW errata NTB: remove duplicate defines NTB: correct dmaengine_get/put usage NTB: Fix ntb_transport link down race ntb: Fix missed call to pci_enable_msix() NTB: Fix NTB-RP Link Up NTB: Xeon Doorbell errata workaround
2013-11-20NTB: Disable interrupts and poll under high loadJon Mason
Disable interrupts and poll under high load Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20NTB: correct dmaengine_get/put usageJon Mason
dmaengine_get() causes the initialization of the per-cpu channel tables. It needs to be called prior to dma_find_channel(). Initial version by Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jon Mason <jon.mason@intel.com>