IB/hfi1: Allow for non-double word multiple message sizes for user SDMA

The driver pads non-double word multiple message sizes but it doesn't
account for this padding when the packet length is calculated. Also, the
data length is miscalculated for message sizes less than 4 bytes due to
the bit representation in LRH. And there's a check for non-double word
multiple message sizes that prevents these messages from being sent.
This patch fixes length miscalculations and enables the functionality to
send non-double word multiple message sizes.

Reviewed-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/hfi1/user_sdma.c b/drivers/infiniband/hw/hfi1/user_sdma.c
index d16ed52..1e266c9 100644 (file)
--- a/drivers/infiniband/hw/hfi1/user_sdma.c
+++ b/drivers/infiniband/hw/hfi1/user_sdma.c
@@ -793,14 +793,21 @@ static inline u32 compute_data_length(struct user_sdma_request *req,
         * The size of the data of the first packet is in the header
         * template. However, it includes the header and ICRC, which need
         * to be subtracted.
+        * The minimum representable packet data length in a header is 4 bytes,
+        * therefore, when the data length request is less than 4 bytes, there's
+        * only one packet, and the packet data length is equal to that of the
+        * request data length.
         * The size of the remaining packets is the minimum of the frag
         * size (MTU) or remaining data in the request.
         */
        u32 len;
 
        if (!req->seqnum) {
-               len = ((be16_to_cpu(req->hdr.lrh[2]) << 2) -
-                      (sizeof(tx->hdr) - 4));
+               if (req->data_len < sizeof(u32))
+                       len = req->data_len;
+               else
+                       len = ((be16_to_cpu(req->hdr.lrh[2]) << 2) -
+                              (sizeof(tx->hdr) - 4));
        } else if (req_opcode(req->info.ctrl) == EXPECTED) {
                u32 tidlen = EXP_TID_GET(req->tids[req->tididx], LEN) *
                        PAGE_SIZE;
@@ -830,6 +837,13 @@ static inline u32 compute_data_length(struct user_sdma_request *req,
        return len;
 }
 
+static inline u32 pad_len(u32 len)
+{
+       if (len & (sizeof(u32) - 1))
+               len += sizeof(u32) - (len & (sizeof(u32) - 1));
+       return len;
+}
+
 static inline u32 get_lrh_len(struct hfi1_pkt_header hdr, u32 len)
 {
        /* (Size of complete header - size of PBC) + 4B ICRC + data length */
@@ -921,7 +935,8 @@ static int user_sdma_send_pkts(struct user_sdma_request *req, unsigned maxpkts)
                if (test_bit(SDMA_REQ_HAVE_AHG, &req->flags)) {
                        if (!req->seqnum) {
                                u16 pbclen = le16_to_cpu(req->hdr.pbc[0]);
-                               u32 lrhlen = get_lrh_len(req->hdr, datalen);
+                               u32 lrhlen = get_lrh_len(req->hdr,
+                                                        pad_len(datalen));
                                /*
                                 * Copy the request header into the tx header
                                 * because the HW needs a cacheline-aligned
@@ -1219,16 +1234,14 @@ static int check_header_template(struct user_sdma_request *req,
        /*
         * Perform safety checks for any type of packet:
         *    - transfer size is multiple of 64bytes
-        *    - packet length is multiple of 4bytes
-        *    - entire request length is multiple of 4bytes
+        *    - packet length is multiple of 4 bytes
         *    - packet length is not larger than MTU size
         *
         * These checks are only done for the first packet of the
         * transfer since the header is "given" to us by user space.
         * For the remainder of the packets we compute the values.
         */
-       if (req->info.fragsize % PIO_BLOCK_SIZE ||
-           lrhlen & 0x3 || req->data_len & 0x3  ||
+       if (req->info.fragsize % PIO_BLOCK_SIZE || lrhlen & 0x3 ||
            lrhlen > get_lrh_len(*hdr, req->info.fragsize))
                return -EINVAL;
 
@@ -1290,7 +1303,7 @@ static int set_txreq_header(struct user_sdma_request *req,
        struct hfi1_pkt_header *hdr = &tx->hdr;
        u16 pbclen;
        int ret;
-       u32 tidval = 0, lrhlen = get_lrh_len(*hdr, datalen);
+       u32 tidval = 0, lrhlen = get_lrh_len(*hdr, pad_len(datalen));
 
        /* Copy the header template to the request before modification */
        memcpy(hdr, &req->hdr, sizeof(*hdr));
@@ -1401,7 +1414,7 @@ static int set_txreq_header_ahg(struct user_sdma_request *req,
        struct hfi1_user_sdma_pkt_q *pq = req->pq;
        struct hfi1_pkt_header *hdr = &req->hdr;
        u16 pbclen = le16_to_cpu(hdr->pbc[0]);
-       u32 val32, tidval = 0, lrhlen = get_lrh_len(*hdr, len);
+       u32 val32, tidval = 0, lrhlen = get_lrh_len(*hdr, pad_len(len));
 
        if (PBC2LRH(pbclen) != lrhlen) {
                /* PBC.PbcLengthDWs */

diff --git a/include/uapi/rdma/hfi/hfi1_user.h b/include/uapi/rdma/hfi/hfi1_user.h
index 98bebf8..d15e728 100644 (file)
--- a/include/uapi/rdma/hfi/hfi1_user.h
+++ b/include/uapi/rdma/hfi/hfi1_user.h
@@ -75,7 +75,7 @@
  * may not be implemented; the user code must deal with this if it
  * cares, or it must abort after initialization reports the difference.
  */
-#define HFI1_USER_SWMINOR 1
+#define HFI1_USER_SWMINOR 2
 
 /*
  * We will encode the major/minor inside a single 32bit version number.