diff options
Diffstat (limited to 'net/sunrpc/xprtrdma/xprt_rdma.h')
| -rw-r--r-- | net/sunrpc/xprtrdma/xprt_rdma.h | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 3d7e9c9bad1f..852dd0a750a5 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -305,16 +305,19 @@ struct rpcrdma_mr_seg { /* chunk descriptors */ char *mr_offset; /* kva if no page, else offset */ }; -/* Reserve enough Send SGEs to send a maximum size inline request: +/* The Send SGE array is provisioned to send a maximum size + * inline request: * - RPC-over-RDMA header * - xdr_buf head iovec - * - RPCRDMA_MAX_INLINE bytes, possibly unaligned, in pages + * - RPCRDMA_MAX_INLINE bytes, in pages * - xdr_buf tail iovec + * + * The actual number of array elements consumed by each RPC + * depends on the device's max_sge limit. */ enum { RPCRDMA_MIN_SEND_SGES = 3, - RPCRDMA_MAX_SEND_PAGES = PAGE_SIZE + RPCRDMA_MAX_INLINE - 1, - RPCRDMA_MAX_PAGE_SGES = (RPCRDMA_MAX_SEND_PAGES >> PAGE_SHIFT) + 1, + RPCRDMA_MAX_PAGE_SGES = RPCRDMA_MAX_INLINE >> PAGE_SHIFT, RPCRDMA_MAX_SEND_SGES = 1 + 1 + RPCRDMA_MAX_PAGE_SGES + 1, }; |