RDMA/nes: Fix bugs in nes_reg_phys_mr()

The code incorrectly failed memory registration if the buffer was not
page aligned.  Also, the length field is mangled causing the hardware
to think the registration is much larger than it really is.

The fix is to remove the page alignment restriction as well the
incorrect length adjustment.  Also make sure that all buffers after
the first start at a page boundary, and all buffers except the last
end on a page boundary.
Signed-off-by: Don Wood <donald.e.wood@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/hw/nes/nes_verbs.c

@@ -2122,6 +2122,7 @@ static struct ib_mr *nes_reg_phys_mr(struct ib_pd *ib_pd,
 	struct nes_root_vpbl root_vpbl;
 	u32 stag;
 	u32 i;
+	unsigned long mask;
 	u32 stag_index = 0;
 	u32 next_stag_index = 0;
 	u32 driver_key = 0;
@@ -2150,6 +2151,9 @@ static struct ib_mr *nes_reg_phys_mr(struct ib_pd *ib_pd,
 		return ERR_PTR(-E2BIG);
 	}
 
+	if ((buffer_list[0].addr ^ *iova_start) & ~PAGE_MASK)
+		return ERR_PTR(-EINVAL);
+
 	err = nes_alloc_resource(nesadapter, nesadapter->allocated_mrs, nesadapter->max_mr,
 			&stag_index, &next_stag_index);
 	if (err) {
@@ -2215,19 +2219,16 @@ static struct ib_mr *nes_reg_phys_mr(struct ib_pd *ib_pd,
 			root_pbl_index++;
 			cur_pbl_index = 0;
 		}
-		if (buffer_list[i].addr & ~PAGE_MASK) {
-			/* TODO: Unwind allocated buffers */
-			nes_free_resource(nesadapter, nesadapter->allocated_mrs, stag_index);
-			nes_debug(NES_DBG_MR, "Unaligned Memory Buffer: 0x%x\n",
-					(unsigned int) buffer_list[i].addr);
-			ibmr = ERR_PTR(-EINVAL);
-			kfree(nesmr);
-			goto reg_phys_err;
-		}
 
-		if (!buffer_list[i].size) {
+		mask = !buffer_list[i].size;
+		if (i != 0)
+			mask |= buffer_list[i].addr;
+		if (i != num_phys_buf - 1)
+			mask |= buffer_list[i].addr + buffer_list[i].size;
+
+		if (mask & ~PAGE_MASK) {
 			nes_free_resource(nesadapter, nesadapter->allocated_mrs, stag_index);
-			nes_debug(NES_DBG_MR, "Invalid Buffer Size\n");
+			nes_debug(NES_DBG_MR, "Invalid buffer addr or size\n");
 			ibmr = ERR_PTR(-EINVAL);
 			kfree(nesmr);
 			goto reg_phys_err;
@@ -2238,7 +2239,7 @@ static struct ib_mr *nes_reg_phys_mr(struct ib_pd *ib_pd,
 			if ((buffer_list[i-1].addr+PAGE_SIZE) != buffer_list[i].addr)
 				single_page = 0;
 		}
-		vpbl.pbl_vbase[cur_pbl_index].pa_low = cpu_to_le32((u32)buffer_list[i].addr);
+		vpbl.pbl_vbase[cur_pbl_index].pa_low = cpu_to_le32((u32)buffer_list[i].addr & PAGE_MASK);
 		vpbl.pbl_vbase[cur_pbl_index++].pa_high =
 				cpu_to_le32((u32)((((u64)buffer_list[i].addr) >> 32)));
 	}
@@ -2251,8 +2252,6 @@ static struct ib_mr *nes_reg_phys_mr(struct ib_pd *ib_pd,
 			" length = 0x%016lX, index = 0x%08X\n",
 			stag, (unsigned long)*iova_start, (unsigned long)region_length, stag_index);
 
-	region_length -= (*iova_start)&PAGE_MASK;
-
 	/* Make the leaf PBL the root if only one PBL */
 	if (root_pbl_index == 1) {
 		root_vpbl.pbl_pbase = vpbl.pbl_pbase;