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path: root/drivers/ntb/ntb_transport.c (follow)
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2014-09-14ntb: Add alignment check to meet hardware requirementDave Jiang1-0/+13
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 Mason1-2/+2
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 Mason1-10/+9
Some white space and 80 char overruns corrected. Signed-off-by: Jon Mason <jon.mason@intel.com>
2014-04-07NTB: client event cleanupJon Mason1-1/+0
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 Torvalds1-36/+41
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 Mason1-18/+7
Disable interrupts and poll under high load Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-20NTB: correct dmaengine_get/put usageJon Mason1-3/+6
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>
2013-11-20NTB: Fix ntb_transport link down raceJon Mason1-15/+28
A WARN_ON is being hit in ntb_qp_link_work due to the NTB transport link being down while the ntb qp link is still active. This is caused by the transport link being brought down prior to the qp link worker thread being terminated. To correct this, shutdown the qp's prior to bringing the transport link down. Also, only call the qp worker thread if it is in interrupt context, otherwise call the function directly. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-11-14dmaengine: remove DMA unmap flagsBartlomiej Zolnierkiewicz1-8/+3
Remove no longer needed DMA unmap flags: - DMA_COMPL_SKIP_SRC_UNMAP - DMA_COMPL_SKIP_DEST_UNMAP - DMA_COMPL_SRC_UNMAP_SINGLE - DMA_COMPL_DEST_UNMAP_SINGLE Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Jon Mason <jon.mason@intel.com> Acked-by: Mark Brown <broonie@linaro.org> [djbw: clean up straggling skip unmap flags in ntb] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2013-11-14NTB: convert to dmaengine_unmap_dataBartlomiej Zolnierkiewicz1-27/+58
Use the generic unmap object to unmap dma buffers. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Jon Mason <jon.mason@intel.com> [djbw: fix up unmap len, and GFP flags] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2013-09-05NTB: Comment FixJon Mason1-2/+2
Add "data" ntb_register_db_callback parameter description comment and correct poor spelling. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05NTB: Remove unused variableJon Mason1-3/+0
Remove unused pci_dev variable from ntb_transport_free() Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05NTB: Rename Variables for NTB-RPJon Mason1-1/+1
Many variable names in the NTB driver refer to the primary or secondary side. However, these variables will be used to access the reverse case when in NTB-RP mode. Make these names more generic in anticipation of NTB-RP support. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-05NTB: Use DMA Engine to Transmit and ReceiveJon Mason1-47/+277
Allocate and use a DMA engine channel to transmit and receive data over NTB. If none is allocated, fall back to using the CPU to transfer data. Signed-off-by: Jon Mason <jon.mason@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
2013-09-03NTB: Xeon Errata WorkaroundJon Mason1-29/+49
There is a Xeon hardware errata related to writes to SDOORBELL or B2BDOORBELL in conjunction with inbound access to NTB MMIO Space, which may hang the system. To workaround this issue, use one of the memory windows to access the interrupt and scratch pad registers on the remote system. This bypasses the issue, but removes one of the memory windows from use by the transport. This reduction of MWs necessitates adding some logic to determine the number of available MWs. Since some NTB usage methodologies may have unidirectional traffic, the ability to disable the workaround via modparm has been added. See BF113 in http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/xeon-c5500-c3500-spec-update.pdf See BT119 in http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/xeon-e5-family-spec-update.pdf Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-09-03NTB: Correct debugfs to work with more than 1 NTB DeviceJon Mason1-12/+5
Debugfs was setup in NTB to only have a single debugfs directory. This resulted in the leaking of debugfs directories and files when multiple NTB devices were present, due to each device stomping on the variables containing the previous device's values (thus preventing them from being freed on cleanup). Correct this by creating a secondary directory of the PCI BDF for each device present, and nesting the previously existing information in those directories. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15NTB: Multiple NTB client fixJon Mason1-2/+3
Fix issue with adding multiple ntb client devices to the ntb virtual bus. Previously, multiple devices would be added with the same name, resulting in crashes. To get around this issue, add a unique number to the device when it is added. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15NTB: memcpy lockup workaroundJon Mason1-3/+8
The system will appear to lockup for long periods of time due to the NTB driver spending too much time in memcpy. Avoid this by reducing the number of packets that can be serviced on a given interrupt. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15NTB: Correctly handle receive buffers of the minimal sizeJon Mason1-3/+5
The ring logic of the NTB receive buffer/transmit memory window requires there to be at least 2 payload sized allotments. For the minimal size case, split the buffer into two and set the transport_mtu to the appropriate size. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15NTB: reset tx_index on link toggleJon Mason1-1/+1
If the NTB link toggles, the driver could stop receiving due to the tx_index not being set to 0 on the transmitting size on a link-up event. This is due to the driver expecting the incoming data to start at the beginning of the receive buffer and not at a random place. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15NTB: Link toggle memory leakJon Mason1-12/+20
Each link-up will allocate a new NTB receive buffer when the NTB properties are negotiated with the remote system. These allocations did not check for existing buffers and thus did not free them. Now, the driver will check for an existing buffer and free it if not of the correct size, before trying to alloc a new one. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15NTB: Handle 64bit BAR sizesJon Mason1-48/+73
64bit BAR sizes are permissible with an NTB device. To support them various modifications and clean-ups were required, most significantly using 2 32bit scratch pad registers for each BAR. Also, modify the driver to allow more than 2 Memory Windows. Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15NTB: fix pointer math issuesDan Carpenter1-2/+2
->remote_rx_info and ->rx_info are struct ntb_rx_info pointers. If we add sizeof(struct ntb_rx_info) then it goes too far. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-05-15NTB: variable dereferenced before checkJon Mason1-2/+14
Correct instances of variable dereferencing before checking its value on the functions exported to the client drivers. Also, add sanity checks for all exported functions. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jon Mason <jon.mason@intel.com>
2013-01-21NTB: Fix Sparse WarningsJon Mason1-16/+16
Address the sparse warnings and resulting fallout Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: Out of free receive entries issueJon Mason1-3/+6
If the NTB client driver enqueues the maximum number of rx buffers, it will not be able to re-enqueue another in its callback handler due to a lack of free entries. This can be avoided by adding the current entry to the free queue prior to calling the client callback handler. With this change, ntb_netdev will no longer encounter a rx error on its first packet. Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: Remove reads across NTBJon Mason1-74/+63
CPU reads across NTB are slow(er) and can hang the local system if an ECC error is encountered on the remote. To work around the need for a read, have the remote side write its current position in the rx buffer to the local system's buffer and use that to see if there is room when transmitting. Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: correct stack usage warning in debugfs_readJon Mason1-3/+10
Correct gcc warning of using too much stack debugfs_read. This is done by kmallocing the buffer instead of using the char array on stack. Also, shrinking the buffer to something closer to what is currently being used. Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: whitespace cleanupsJon Mason1-24/+16
Whitespace cleanups found via `indent` Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: namespacecheck cleanupsJon Mason1-1/+1
Declare ntb_bus_type static to remove it from name space, and remove unused ntb_get_max_spads function. Found via `make namespacecheck`. Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: use simple_open for debugfsJon Mason1-7/+1
Use simple_open for debugfs instead of recreating it in the NTB driver. Caught by coccicheck. Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: No sleeping in interrupt contextJon Mason1-3/+17
Move all cancel_delayed_work_sync to a work thread to prevent sleeping in interrupt context (when the NTB link goes down). Caught via 'Sleep inside atomic section checking' Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: separate transmit and receive windowsJon Mason1-35/+44
Since it is possible for the memory windows on the two NTB connected systems to be different sizes, the divergent sizes must be accounted for in the segmentation of the MW's on each side. Create separate size variables and initialization as necessary. Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: correct memory barrierJon Mason1-1/+1
mmiowb is not sufficient to flush the data and is causing data corruption. Change to wmb and the data corruption is no more. Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20NTB: Handle ntb client device probes without present hardwareJon Mason1-0/+6
Attempts to probe client ntb drivers without ntb hardware present will result in null pointer dereference due to the lack of the ntb bus device being registers. Check to see if this is the case, and fail all calls by the clients registering their drivers. Signed-off-by: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17ntb: remove __dev* markingsGreg Kroah-Hartman1-2/+2
These are now gone from the kernel, so remove them from the newly-added drivers before they start to cause build errors for people. Cc: Jon Mason <jon.mason@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17PCI-Express Non-Transparent Bridge SupportJon Mason1-0/+1427
A PCI-Express non-transparent bridge (NTB) is a point-to-point PCIe bus connecting 2 systems, providing electrical isolation between the two subsystems. A non-transparent bridge is functionally similar to a transparent bridge except that both sides of the bridge have their own independent address domains. The host on one side of the bridge will not have the visibility of the complete memory or I/O space on the other side of the bridge. To communicate across the non-transparent bridge, each NTB endpoint has one (or more) apertures exposed to the local system. Writes to these apertures are mirrored to memory on the remote system. Communications can also occur through the use of doorbell registers that initiate interrupts to the alternate domain, and scratch-pad registers accessible from both sides. The NTB device driver is needed to configure these memory windows, doorbell, and scratch-pad registers as well as use them in such a way as they can be turned into a viable communication channel to the remote system. ntb_hw.[ch] determines the usage model (NTB to NTB or NTB to Root Port) and abstracts away the underlying hardware to provide access and a common interface to the doorbell registers, scratch pads, and memory windows. These hardware interfaces are exported so that other, non-mainlined kernel drivers can access these. ntb_transport.[ch] also uses the exported interfaces in ntb_hw.[ch] to setup a communication channel(s) and provide a reliable way of transferring data from one side to the other, which it then exports so that "client" drivers can access them. These client drivers are used to provide a standard kernel interface (i.e., Ethernet device) to NTB, such that Linux can transfer data from one system to the other in a standard way. Signed-off-by: Jon Mason <jon.mason@intel.com> Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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