kernel/linux.git/include/rdma/ib_umem.h, branch linux-7.1.y

RDMA: During rereg_mr ensure that REREG_ACCESS is compatible

2026-06-08T16:39:20+00:00

If IB_MR_REREG_ACCESS changes from RO to RW then the umem has to be re-evaluated to ensure it is properly pinned as RW. Since the umem is hidden inside each driver's mr struct add a ib_umem_check_rereg() function that each driver has to call before processing IB_MR_REREG_ACCESS. mlx4 has to retain its duplicate ib_access_writable check because it implements IB_MR_REREG_ACCESS | IB_MR_REREG_TRANS by changing both items in place sequentially while the MR is live, so it will continue to not support this combination. Cc: stable@vger.kernel.org Fixes: b40656aa7d55 ("RDMA/umem: remove FOLL_FORCE usage") Link: https://patch.msgid.link/r/0-v1-06fb1a2d6cf5+107-rereg_access_jgg@nvidia.com Reported-by: Philip Tsukerman Signed-off-by: Jason Gunthorpe

RDMA/umem: Use consistent DMA attributes when unmapping entries

2026-03-30T17:47:45+00:00

The DMA API expects that mapping and unmapping use the same DMA attributes. The RDMA umem code did not meet this requirement, so fix the mismatch. Fixes: f03d9fadfe13 ("RDMA/core: Add weak ordering dma attr to dma mapping") Signed-off-by: Leon Romanovsky

RDMA/umem: Add helpers for umem dmabuf revoke lock

2026-03-08T12:37:38+00:00

Added helpers to acquire and release the umem dmabuf revoke lock. The intent is to avoid the need for drivers to peek into the ib_umem_dmabuf internals to get the dma_resv_lock and bring us one step closer to abstracting ib_umem_dmabuf away from drivers in general. Signed-off-by: Jacob Moroni Link: https://patch.msgid.link/20260305170826.3803155-5-jmoroni@google.com Signed-off-by: Leon Romanovsky

RDMA/umem: Add pinned revocable dmabuf import interface

2026-03-08T12:37:38+00:00

Added an interface for importing a pinned but revocable dmabuf. This interface can be used by drivers that are capable of revocation so that they can import dmabufs from exporters that may require it, such as VFIO. This interface implements a two step process, where drivers will first call ib_umem_dmabuf_get_pinned_revocable_and_lock() which will pin and map the dmabuf (and provide a functional move_notify/invalidate_mappings callback), but will return with the lock still held so that the driver can then populate the callback via ib_umem_dmabuf_set_revoke_locked() without races from concurrent revocations. This scheme also allows for easier integration with drivers that may not have actually allocated their internal MR objects at the time of the get_pinned_revocable* call. Signed-off-by: Jacob Moroni Link: https://patch.msgid.link/20260305170826.3803155-4-jmoroni@google.com Signed-off-by: Leon Romanovsky

RDMA/umem: Remove unnecessary includes and defines from ib_umem header

2026-02-25T13:15:30+00:00

The ib_umem header no longer requires the removed includes or forward declarations, so drop them to reduce clutter. Link: https://patch.msgid.link/20260213-refactor-umem-v1-3-f3be85847922@nvidia.com Signed-off-by: Leon Romanovsky

RDMA/umem: Allow including ib_umem header from any location

2026-02-25T13:15:30+00:00

Including ib_umem.h currently triggers circular dependency errors. These issues can be resolved by removing the include of ib_verbs.h, which was only needed to resolve the struct ib_device pointer. >> depmod: ERROR: Cycle detected: ib_core -> ib_uverbs -> ib_core >> depmod: ERROR: Found 2 modules in dependency cycles! make[3]: *** [scripts/Makefile.modinst:132: depmod] Error 1 make[3]: Target '__modinst' not remade because of errors. make[2]: *** [Makefile:1960: modules_install] Error 2 make[1]: *** [Makefile:248: __sub-make] Error 2 make[1]: Target 'modules_install' not remade because of errors. make: *** [Makefile:248: __sub-make] Error 2 make: Target 'modules_install' not remade because of errors. Link: https://patch.msgid.link/20260213-refactor-umem-v1-2-f3be85847922@nvidia.com Signed-off-by: Leon Romanovsky

RDMA: Move DMA block iterator logic into dedicated files

2026-02-25T13:15:30+00:00

The DMA iterator logic was mixed into verbs and umem-specific code, forcing all users to include rdma/ib_umem.h. Move the block iterator logic into iter.c and rdma/iter.h so that rdma/ib_umem.h and rdma/ib_verbs.h can be separated in a follow-up patch. Link: https://patch.msgid.link/20260213-refactor-umem-v1-1-f3be85847922@nvidia.com Signed-off-by: Leon Romanovsky

RDMA/umem: fix kernel-doc warnings

2026-02-24T10:39:01+00:00

Add or correct kernel-doc comments to eliminate warnings: Warning: include/rdma/ib_umem.h:104 function parameter 'biter' not described in 'rdma_umem_for_each_dma_block' Warning: include/rdma/ib_umem.h:140 function parameter 'pgsz_bitmap' not described in 'ib_umem_find_best_pgoff' Warning: include/rdma/ib_umem.h:141 No description found for return value of 'ib_umem_find_best_pgoff' Signed-off-by: Randy Dunlap Link: https://patch.msgid.link/20260224003120.3173892-1-rdunlap@infradead.org Signed-off-by: Leon Romanovsky

RDMA/core: Add umem "is_contiguous" and "start_dma_addr" helpers

2025-07-13T08:00:34+00:00

In some cases drivers may need to check if a given umem is contiguous. Add a helper function in core code so that drivers don't need to deal with umem or scatter-gather lists structure. Additionally add a helper for getting umem's start DMA address and use it in other helper functions that open code it. Signed-off-by: Michael Margolin Link: https://patch.msgid.link/20250708202308.24783-3-mrgolin@amazon.com Reviewed-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky

RDMA/umem: Introduce an option to revoke DMABUF umem

2024-08-11T08:12:49+00:00

Introduce an option to revoke DMABUF umem. This option will retain the umem allocation while revoking its DMA mapping. Furthermore, any subsequent attempts to map the pages should fail once the umem has been revoked. This functionality will be utilized in the upcoming patches in the series, where we aim to delay umem deallocation until the mkey deregistration. However, we must unmap its pages immediately. Signed-off-by: Yishai Hadas Link: https://patch.msgid.link/a38270f2fe4a194868ca2312f4c1c760e51bcbff.1722512548.git.leon@kernel.org Signed-off-by: Leon Romanovsky