kernel.git/drivers/infiniband/core/rw.c, branch linux-rolling-stable

RDMA/core: add rdma_rw_max_sge() helper for SQ sizing

2026-02-26T22:59:27Z

[ Upstream commit afcae7d7b8a278a6c29e064f99e5bafd4ac1fb37 ] svc_rdma_accept() computes sc_sq_depth as the sum of rq_depth and the number of rdma_rw contexts (ctxts). This value is used to allocate the Send CQ and to initialize the sc_sq_avail credit pool. However, when the device uses memory registration for RDMA operations, rdma_rw_init_qp() inflates the QP's max_send_wr by a factor of three per context to account for REG and INV work requests. The Send CQ and credit pool remain sized for only one work request per context, causing Send Queue exhaustion under heavy NFS WRITE workloads. Introduce rdma_rw_max_sge() to compute the actual number of Send Queue entries required for a given number of rdma_rw contexts. Upper layer protocols call this helper before creating a Queue Pair so that their Send CQs and credit accounting match the QP's true capacity. Update svc_rdma_accept() to use rdma_rw_max_sge() when computing sc_sq_depth, ensuring the credit pool reflects the work requests that rdma_rw_init_qp() will reserve. Reviewed-by: Christoph Hellwig Fixes: 00bd1439f464 ("RDMA/rw: Support threshold for registration vs scattering to local pages") Signed-off-by: Chuck Lever Link: https://patch.msgid.link/20260128005400.25147-5-cel@kernel.org Signed-off-by: Leon Romanovsky Signed-off-by: Sasha Levin

RDMA/core: Fix a couple of obvious typos in comments

2023-10-04T18:55:44Z

Fix typos. Signed-off-by: Chuck Lever Link: https://lore.kernel.org/r/169643338101.8035.6826446669479247727.stgit@manet.1015granger.net Signed-off-by: Leon Romanovsky

RDMA/rw: drop pci_p2pdma_[un]map_sg()

2022-07-26T11:28:07Z

dma_map_sg() now supports the use of P2PDMA pages so pci_p2pdma_map_sg() is no longer necessary and may be dropped. This means the rdma_rw_[un]map_sg() helpers are no longer necessary. Remove it all. Signed-off-by: Logan Gunthorpe Reviewed-by: Jason Gunthorpe Reviewed-by: Christoph Hellwig Signed-off-by: Christoph Hellwig

mm: don't include in

2022-03-03T17:47:33Z

Move the check for the actual pgmap types that need the free at refcount one behavior into the out of line helper, and thus avoid the need to pull memremap.h into mm.h. Link: https://lkml.kernel.org/r/20220210072828.2930359-7-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Logan Gunthorpe Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Acked-by: Felix Kuehling Tested-by: "Sierra Guiza, Alejandro (Alex)" Cc: Alex Deucher Cc: Alistair Popple Cc: Ben Skeggs Cc: Chaitanya Kulkarni Cc: Karol Herbst Cc: Lyude Paul Cc: Miaohe Lin Cc: Muchun Song Cc: "Pan, Xinhui" Cc: Ralph Campbell Signed-off-by: Andrew Morton Signed-off-by: Matthew Wilcox (Oracle)

RDMA/rw: switch to dma_map_sgtable()

2021-10-05T17:49:58Z

There are a couple of subtle error path bugs related to mapping the sgls: - In rdma_rw_ctx_init(), dma_unmap would be called with an sg that could have been incremented from the original call, as well as an nents that is the dma mapped entries not the original number of nents called when mapped. - Similarly in rdma_rw_ctx_signature_init, both sg and prot_sg were unmapped with the incorrect number of nents. To fix this, switch to the sgtable interface for mapping which conveniently stores the original nents for unmapping. This will get cleaned up further once the dma mapping interface supports P2PDMA and pci_p2pdma_map_sg() can be removed. Fixes: 0e353e34e1e7 ("IB/core: add RW API support for signature MRs") Fixes: a060b5629ab0 ("IB/core: generic RDMA READ/WRITE API") Link: https://lore.kernel.org/r/20211001213215.3761-1-logang@deltatee.com Signed-off-by: Logan Gunthorpe Signed-off-by: Jason Gunthorpe

RDMA/core: Fix incorrect print format specifier

2021-06-21T18:38:30Z

There are some '%u' for 'int' and '%d' for 'unsigend int', they should be fixed. Link: https://lore.kernel.org/r/1623325232-30900-1-git-send-email-liweihang@huawei.com Signed-off-by: Wenpeng Liang Signed-off-by: Weihang Li Signed-off-by: Jason Gunthorpe

RDMA: Support more than 255 rdma ports

2021-03-26T12:31:21Z

Current code uses many different types when dealing with a port of a RDMA device: u8, unsigned int and u32. Switch to u32 to clean up the logic. This allows us to make (at least) the core view consistent and use the same type. Unfortunately not all places can be converted. Many uverbs functions expect port to be u8 so keep those places in order not to break UAPIs. HW/Spec defined values must also not be changed. With the switch to u32 we now can support devices with more than 255 ports. U32_MAX is reserved to make control logic a bit easier to deal with. As a device with U32_MAX ports probably isn't going to happen any time soon this seems like a non issue. When a device with more than 255 ports is created uverbs will report the RDMA device as having 255 ports as this is the max currently supported. The verbs interface is not changed yet because the IBTA spec limits the port size in too many places to be u8 and all applications that relies in verbs won't be able to cope with this change. At this stage, we are extending the interfaces that are using vendor channel solely Once the limitation is lifted mlx5 in switchdev mode will be able to have thousands of SFs created by the device. As the only instance of an RDMA device that reports more than 255 ports will be a representor device and it exposes itself as a RAW Ethernet only device CM/MAD/IPoIB and other ULPs aren't effected by this change and their sysfs/interfaces that are exposes to userspace can remain unchanged. While here cleanup some alignment issues and remove unneeded sanity checks (mainly in rdmavt), Link: https://lore.kernel.org/r/20210301070420.439400-1-leon@kernel.org Signed-off-by: Mark Bloch Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA: Use kzalloc for allocating only one thing

2021-01-07T20:47:53Z

Use kzalloc rather than kcalloc(1,...) The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // @@ @@ - kcalloc(1, + kzalloc( ...) // Link: https://lore.kernel.org/r/20201229135223.23815-1-zhengyongjun3@huawei.com Link: https://lore.kernel.org/r/20201229135232.23869-1-zhengyongjun3@huawei.com Signed-off-by: Zheng Yongjun Signed-off-by: Jason Gunthorpe

RDMA/core: remove use of dma_virt_ops

2020-11-17T19:22:07Z

Use the ib_dma_* helpers to skip the DMA translation instead. This removes the last user if dma_virt_ops and keeps the weird layering violation inside the RDMA core instead of burderning the DMA mapping subsystems with it. This also means the software RDMA drivers now don't have to mess with DMA parameters that are not relevant to them at all, and that in the future we can use PCI P2P transfers even for software RDMA, as there is no first fake layer of DMA mapping that the P2P DMA support. Link: https://lore.kernel.org/r/20201106181941.1878556-8-hch@lst.de Signed-off-by: Christoph Hellwig Tested-by: Mike Marciniszyn Signed-off-by: Jason Gunthorpe

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59Z

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva