BMC/Intel-BMC/linux.git/include/rdma/uverbs_ioctl.h, branch dev-4.19

IB/uverbs: Remove struct uverbs_root_spec and all supporting code

2018-08-13T15:17:19+00:00

Everything now uses the uverbs_uapi data structure. Signed-off-by: Jason Gunthorpe

IB/uverbs: Use uverbs_api to unmarshal ioctl commands

2018-08-13T15:17:16+00:00

Convert the ioctl method syscall path to use the uverbs_api data structures. The new uapi structure includes all the same information, just in a different and more optimal way. - Use attr_bkey instead of 2 level radix trees for everything related to attributes. This includes the attribute storage, presence, and detection of missing mandatory attributes. - Avoid iterating over all attribute storage at finish, instead use find_first_bit with the attr_bkey to locate only those attrs that need cleanup. - Organize things to always run, and always rely on, cleanup. This avoids a bunch of tricky error unwind cases. - Locate the method using the radix tree, and locate the attributes using a very efficient incremental radix tree lookup - Use the precomputed destroy_bkey to handle uobject destruction - Use the precomputed allocation sizes and precomputed 'need_stack' to avoid maths in the fast path. This is optimal if userspace does not pass (many) unsupported attributes. Overall this results in much better codegen for the attribute accessors, everything is now stored in bitmaps or linear arrays indexed by attr_bkey. The compiler can compute attr_bkey values at compile time for all method attributes, meaning things like uverbs_attr_is_valid() now compile into single instruction bit tests. Signed-off-by: Jason Gunthorpe

IB/uverbs: Add a simple allocator to uverbs_attr_bundle

2018-08-13T15:16:08+00:00

This is similar in spirit to devm, it keeps track of any allocations linked to this method call and ensures they are all freed when the method exits. Further, if there is space in the internal/onstack buffer then the allocator will hand out that memory and avoid an expensive call to kalloc/kfree in the syscall path. Signed-off-by: Jason Gunthorpe Reviewed-by: Leon Romanovsky

IB/uverbs: Remove the ib_uverbs_attr pointer from each attr

2018-08-10T22:06:24+00:00

Memory in the bundle is valuable, do not waste it holding an 8 byte pointer for the rare case of writing to a PTR_OUT. We can compute the pointer by storing a small 1 byte array offset and the base address of the uattr memory in the bundle private memory. This also means we can access the kernel's copy of the ib_uverbs_attr, so drop the copy of flags as well. Since the uattr base should be private bundle information this also de-inlines the already too big uverbs_copy_to inline and moves create_udata into uverbs_ioctl.c so they can see the private struct definition. Signed-off-by: Jason Gunthorpe Reviewed-by: Leon Romanovsky

IB/uverbs: Provide implementation private memory for the uverbs_attr_bundle

2018-08-10T22:06:24+00:00

This already existed as the anonymous 'ctx' structure, but this was not really a useful form. Hoist this struct into bundle_priv and rework the internal things to use it instead. Move a bunch of the processing internal state into the priv and reduce the excessive use of function arguments. Signed-off-by: Jason Gunthorpe Reviewed-by: Leon Romanovsky

IB/uverbs: Build the specs into a radix tree at runtime

2018-08-10T22:06:24+00:00

This radix tree datastructure is intended to replace the 'hash' structure used today for parsing ioctl methods during system calls. This first commit introduces the structure and builds it from the existing .rodata descriptions. The so-called hash arrangement is actually a 5 level open coded radix tree. This new version uses a 3 level radix tree built using the radix tree library. Overall this is much less code and much easier to build as the radix tree API allows for dynamic modification during the building. There is a small memory penalty to pay for this, but since the radix tree is allocated on a per device basis, a few kb of RAM seems immaterial considering the gained simplicity. The radix tree is similar to the existing tree, but also has a 'attr_bkey' concept, which is a small value'd index for each method attribute. This is used to simplify and improve performance of everything in the next patches. Signed-off-by: Jason Gunthorpe Reviewed-by: Leon Romanovsky Reviewed-by: Michael J. Ruhl

IB/uverbs: Do not pass struct ib_device to the ioctl methods

2018-08-01T20:55:48+00:00

This does the same as the patch before, except for ioctl. The rules are the same, but for the ioctl methods the core code handles setting up the uobject. - Retrieve the ib_dev from the uobject->context->device. This is safe under ioctl as the core has already done rdma_alloc_begin_uobject and so CREATE calls are entirely protected by the rwsem. - Retrieve the ib_dev from uobject->object - Call ib_uverbs_get_ucontext() Signed-off-by: Jason Gunthorpe

IB/uverbs: Add UVERBS_ATTR_FLAGS_IN to the specs language

2018-07-31T02:23:29+00:00

This clearly indicates that the input is a bitwise combination of values in an enum, and identifies which enum contains the definition of the bits. Special accessors are provided that handle the mandatory validation of the allowed bits and enforce the correct type for bitwise flags. If we had introduced this at the start then the kabi would have uniformly used u64 data to pass flags, however today there is a mixture of u64 and u32 flags. All places are converted to accept both sizes and the accessor fixes it. This allows all existing flags to grow to u64 in future without any hassle. Finally all flags are, by definition, optional. If flags are not passed the accessor does not fail, but provides a value of zero. Signed-off-by: Jason Gunthorpe Reviewed-by: Leon Romanovsky

IB/uverbs: Fix locking around struct ib_uverbs_file ucontext

2018-07-25T20:21:46+00:00

We have a parallel unlocked reader and writer with ib_uverbs_get_context() vs everything else, and nothing guarantees this works properly. Audit and fix all of the places that access ucontext to use one of the following locking schemes: - Call ib_uverbs_get_ucontext() under SRCU and check for failure - Access the ucontext through an struct ib_uobject context member while holding a READ or WRITE lock on the uobject. This value cannot be NULL and has no race. - Hold the ucontext_lock and check for ufile->ucontext !NULL This also re-implements ib_uverbs_get_ucontext() in a way that is safe against concurrent ib_uverbs_get_context() and disassociation. As a side effect, every access to ucontext in the commands is via ib_uverbs_get_context() with an error check, or via the uobject, so there is no longer any need for the core code to check ucontext on every command call. These checks are also removed. Signed-off-by: Jason Gunthorpe

IB/mlx5: Introduce flow steering matcher uapi object

2018-07-24T19:34:37+00:00

Introduce flow steering matcher object and its create and destroy methods. This matcher object holds some mlx5 specific driver properties that matches the underlay device specification when an mlx5 flow steering group is created. It will be used in downstream patches to be part of mlx5 specific create flow method. Signed-off-by: Yishai Hadas Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe