Revert "IB/core: Add support for extended query device caps"

While commit 7e36ef8205ff ("IB/core: Temporarily disable
ex_query_device uverb") is correct as it makes the extended
QUERY_DEVICE uverb (which came as part of commit 5a77abf9a97a
("IB/core: Add support for extended query device caps") and commit
860f10a799c8 ("IB/core: Add flags for on demand paging support")) not
available to userspace, it doesn't address the initial issue regarding
ib_copy_to_udata() [1][2].

Additionally, further discussions around this new uverb seems to
conclude it would require a different data structure than the one
currently described in <rdma/ib_user_verbs.h> [3].

Both of these issues require a revert of the changes, so this patch
partially reverts commit 8cdd312cfed7 ("IB/mlx5: Implement the ODP
capability query verb") and commit 860f10a799c8 ("IB/core: Add flags
for on demand paging support") and fully reverts commit 5a77abf9a97a
("IB/core: Add support for extended query device caps").

[1] "Re: [PATCH v3 06/17] IB/core: Add support for extended query device caps"
    http://mid.gmane.org/1418733236.2779.26.camel@opteya.com

[2] "Re: [PATCH] IB/core: Temporarily disable ex_query_device uverb"
    http://mid.gmane.org/1423067503.3030.83.camel@opteya.com

[3] "RE: [PATCH v1 1/5] IB/uverbs: ex_query_device: answer must not depend on request's comp_mask"
    http://mid.gmane.org/2807E5FD2F6FDA4886F6618EAC48510E0CC12C30@CRSMSX101.amr.corp.intel.com

Cc: Eli Cohen <eli@mellanox.com>
Cc: Haggai Eran <haggaie@mellanox.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Shachar Raindel <raindel@mellanox.com>
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 1 insertions, 4 deletions

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 0d74f1de99aa..65994a19e840 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -1707,10 +1707,7 @@ static inline int ib_copy_from_udata(void *dest, struct ib_udata *udata, size_t
 
 static inline int ib_copy_to_udata(struct ib_udata *udata, void *src, size_t len)
 {
-        size_t copy_sz;
-
-        copy_sz = min_t(size_t, len, udata->outlen);
-        return copy_to_user(udata->outbuf, src, copy_sz) ? -EFAULT : 0;
+        return copy_to_user(udata->outbuf, src, len) ? -EFAULT : 0;
 }
 
 /**