LU-10157 lnet: restore an maximal fragments count

Lowering a number of fragments blocks a connection from older clients
who wantsto use 256 fragments to transfer. Let's restore this number
to the original value.

Fixes: 272e49ce2d5d ("LU-10157 lnet: make LNET_MAX_IOV dependent on page size")

Test-Parameters: trivial testlist=lnet-selftest,sanity-lnet
Cray-bug-id: LUS-8139
Signed-off-by: Alexey Lyashkov <c17817@cray.com>
Change-Id: Ia23aa1fb3d36a65abab6241c9ba75addc1dcce0a
Reviewed-on: https://review.whamcloud.com/37385
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Serguei Smirnov <ssmirnov@whamcloud.com>
Reviewed-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lnet/include/lnet/lib-types.h b/lnet/include/lnet/lib-types.h
index 76ac7e3..c4b6222 100644 (file)
--- a/lnet/include/lnet/lib-types.h
+++ b/lnet/include/lnet/lib-types.h
@@ -54,7 +54,8 @@
 /* Max payload size */
 #define LNET_MAX_PAYLOAD       LNET_MTU
 
-#define LNET_MAX_IOV           (LNET_MAX_PAYLOAD >> PAGE_SHIFT)
+/** limit on the number of fragments in discontiguous MDs */
+#define LNET_MAX_IOV   256
 
 /*
  * This is the maximum health value.