android_kernel_xiaomi_sm8350/include/rdma
Roland Dreier f7c6a7b5d5 IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules
Export ib_umem_get()/ib_umem_release() and put low-level drivers in
control of when to call ib_umem_get() to pin and DMA map userspace,
rather than always calling it in ib_uverbs_reg_mr() before calling the
low-level driver's reg_user_mr method.

Also move these functions to be in the ib_core module instead of
ib_uverbs, so that driver modules using them do not depend on
ib_uverbs.

This has a number of advantages:
 - It is better design from the standpoint of making generic code a
   library that can be used or overridden by device-specific code as
   the details of specific devices dictate.
 - Drivers that do not need to pin userspace memory regions do not
   need to take the performance hit of calling ib_mem_get().  For
   example, although I have not tried to implement it in this patch,
   the ipath driver should be able to avoid pinning memory and just
   use copy_{to,from}_user() to access userspace memory regions.
 - Buffers that need special mapping treatment can be identified by
   the low-level driver.  For example, it may be possible to solve
   some Altix-specific memory ordering issues with mthca CQs in
   userspace by mapping CQ buffers with extra flags.
 - Drivers that need to pin and DMA map userspace memory for things
   other than memory regions can use ib_umem_get() directly, instead
   of hacks using extra parameters to their reg_phys_mr method.  For
   example, the mlx4 driver that is pending being merged needs to pin
   and DMA map QP and CQ buffers, but it does not need to create a
   memory key for these buffers.  So the cleanest solution is for mlx4
   to call ib_umem_get() in the create_qp and create_cq methods.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-08 18:00:37 -07:00
..
ib_addr.h
ib_cache.h
ib_cm.h
ib_fmr_pool.h
ib_mad.h PCI: Cleanup the includes of <linux/pci.h> 2007-05-02 19:02:35 -07:00
ib_marshall.h
ib_pack.h
ib_sa.h
ib_smi.h
ib_umem.h IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules 2007-05-08 18:00:37 -07:00
ib_user_cm.h
ib_user_mad.h
ib_user_sa.h
ib_user_verbs.h
ib_verbs.h IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules 2007-05-08 18:00:37 -07:00
iw_cm.h
Kbuild
rdma_cm_ib.h RDMA/cma: Add multicast communication support 2007-02-16 14:29:07 -08:00
rdma_cm.h RDMA/cma: Add multicast communication support 2007-02-16 14:29:07 -08:00
rdma_user_cm.h RDMA/cma: Add multicast communication support 2007-02-16 14:29:07 -08:00