The lookup_mr() function returns NULL on error. It never returns error
pointers.
Fixes: 9284bc34c7 ("RDMA/rxe: Enable asynchronous prefetch for ODP MRs")
Fixes: 3576b0df15 ("RDMA/rxe: Implement synchronous prefetch for ODP MRs")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/685c1430.050a0220.18b0ef.da83@mx.google.com
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
hmm_pfn_to_page() does not return NULL. ib_umem_odp_map_dma_and_lock()
should return an error in case the target pages cannot be mapped until
timeout, so these checks can safely be removed.
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Signed-off-by: Daisuke Matsuda <dskmtsd@gmail.com>
Link: https://patch.msgid.link/20250611162758.10000-1-dskmtsd@gmail.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Calling ibv_advise_mr(3) with flags other than IBV_ADVISE_MR_FLAG_FLUSH
invokes an asynchronous request. It is best-effort, and thus can safely be
deferred to the system-wide workqueue.
The reference counter in rxe_mr is used to ensure that the MRs persist and
that rxe is not terminated until the queued work is done.
Signed-off-by: Daisuke Matsuda <dskmtsd@gmail.com>
Link: https://patch.msgid.link/20250522111955.3227-3-dskmtsd@gmail.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Minimal implementation of ibv_advise_mr(3) requires synchronous calls being
successful with the IBV_ADVISE_MR_FLAG_FLUSH flag. Asynchronous requests,
which are best-effort, will be supported subsequently.
Signed-off-by: Daisuke Matsuda <dskmtsd@gmail.com>
Link: https://patch.msgid.link/20250522111955.3227-2-dskmtsd@gmail.com
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Reuse newly added DMA API to cache IOVA and only link/unlink pages
in fast path for UMEM ODP flow.
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
As a preparation to remove dma_list, store access mask in PFN pointer
and not in dma_addr_t.
Tested-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Major linux distibutions have phased out support for 32-bit machines. Since
rxe is primarily used for development and testing, the benefit of
maintaining 32-bit support is minimal. This change simplifies ATOMIC WRITE
implementations and improves maintainability of the driver.
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Link: https://patch.msgid.link/20250421025101.3588139-1-matsuda-daisuke@fujitsu.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Some functions return int values while they are defined as enum resp_states
variables. This patch resolves the mismatches in rxe.
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Link: https://patch.msgid.link/20250409102701.1275265-1-matsuda-daisuke@fujitsu.com
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
For persistent memories, add rxe_odp_flush_pmem_iova() so that ODP specific
steps are executed. Otherwise, no additional consideration is required.
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Link: https://patch.msgid.link/20250324075649.3313968-2-matsuda-daisuke@fujitsu.com
Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
rxe_mr_do_atomic_op() returns enum resp_states numbers, so the ODP
counterpart must not return raw errno codes.
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Link: https://patch.msgid.link/20250313064540.2619115-1-matsuda-daisuke@fujitsu.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Use a meaningful constant explicitly instead of hard-coding a literal.
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Link: https://patch.msgid.link/20250312065937.1787241-1-matsuda-daisuke@fujitsu.com
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Enable 'fetch and add' and 'compare and swap' operations to be used with
ODP. This is comprised of the following steps:
1. Check the driver page table(umem_odp->dma_list) to see if the target
page is both readable and writable.
2. If not, then trigger page fault to map the page.
3. Convert its user space address to a kernel logical address using PFNs
in the driver page table(umem_odp->pfn_list).
4. Execute the operation.
Link: https://patch.msgid.link/r/20241220100936.2193541-6-matsuda-daisuke@fujitsu.com
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
rxe_mr_copy() is used widely to copy data to/from a user MR. requester uses
it to load payloads of requesting packets; responder uses it to process
Send, Write, and Read operaetions; completer uses it to copy data from
response packets of Read and Atomic operations to a user MR.
Allow these operations to be used with ODP by adding a subordinate function
rxe_odp_mr_copy(). It is comprised of the following steps:
1. Check the driver page table(umem_odp->dma_list) to see if pages being
accessed are present with appropriate permission.
2. If necessary, trigger page fault to map the pages.
3. Convert their user space addresses to kernel logical addresses using
PFNs in the driver page table(umem_odp->pfn_list).
4. Execute data copy to/from the pages.
Link: https://patch.msgid.link/r/20241220100936.2193541-5-matsuda-daisuke@fujitsu.com
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Allow userspace to register an ODP-enabled MR, in which case the flag
IB_ACCESS_ON_DEMAND is passed to rxe_reg_user_mr(). However, there is no
RDMA operation enabled right now. They will be supported later in the
subsequent two patches.
rxe_odp_do_pagefault() is called to initialize an ODP-enabled MR. It syncs
process address space from the CPU page table to the driver page table
(dma_list/pfn_list in umem_odp) when called with RXE_PAGEFAULT_SNAPSHOT
flag. Additionally, It can be used to trigger page fault when pages being
accessed are not present or do not have proper read/write permissions, and
possibly to prefetch pages in the future.
Link: https://patch.msgid.link/r/20241220100936.2193541-4-matsuda-daisuke@fujitsu.com
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
On page invalidation, an MMU notifier callback is invoked to unmap DMA
addresses and update the driver page table(umem_odp->dma_list). The
callback is registered when an ODP-enabled MR is created.
Link: https://patch.msgid.link/r/20241220100936.2193541-3-matsuda-daisuke@fujitsu.com
Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
