RDMA/ucm: Removed checks for unsigned value < 0

cmd is unsigned, no need to check for < 0.  Found by code inspection.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/core/ucm.c

@@ -1122,7 +1122,7 @@ static ssize_t ib_ucm_write(struct file *filp, const char __user *buf,
 	if (copy_from_user(&hdr, buf, sizeof(hdr)))
 		return -EFAULT;
 
-	if (hdr.cmd < 0 || hdr.cmd >= ARRAY_SIZE(ucm_cmd_table))
+	if (hdr.cmd >= ARRAY_SIZE(ucm_cmd_table))
 		return -EINVAL;
 
 	if (hdr.in + sizeof(hdr) > len)

drivers/infiniband/core/ucma.c

@@ -1270,7 +1270,7 @@ static ssize_t ucma_write(struct file *filp, const char __user *buf,
 	if (copy_from_user(&hdr, buf, sizeof(hdr)))
 		return -EFAULT;
 
-	if (hdr.cmd < 0 || hdr.cmd >= ARRAY_SIZE(ucma_cmd_table))
+	if (hdr.cmd >= ARRAY_SIZE(ucma_cmd_table))
 		return -EINVAL;
 
 	if (hdr.in + sizeof(hdr) > len)

drivers/infiniband/core/user_mad.c

@@ -458,8 +458,7 @@ static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
 		goto err;
 	}
 
-	if (packet->mad.hdr.id < 0 ||
-	    packet->mad.hdr.id >= IB_UMAD_MAX_AGENTS) {
+	if (packet->mad.hdr.id >= IB_UMAD_MAX_AGENTS) {
 		ret = -EINVAL;
 		goto err;
 	}
@@ -703,7 +702,7 @@ static int ib_umad_unreg_agent(struct ib_umad_file *file, u32 __user *arg)
 	mutex_lock(&file->port->file_mutex);
 	mutex_lock(&file->mutex);
 
-	if (id < 0 || id >= IB_UMAD_MAX_AGENTS || !__get_agent(file, id)) {
+	if (id >= IB_UMAD_MAX_AGENTS || !__get_agent(file, id)) {
 		ret = -EINVAL;
 		goto out;
 	}

drivers/infiniband/core/uverbs_main.c

@@ -557,8 +557,7 @@ static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 	if (hdr.in_words * 4 != count)
 		return -EINVAL;
 
-	if (hdr.command < 0				||
-	    hdr.command >= ARRAY_SIZE(uverbs_cmd_table) ||
+	if (hdr.command >= ARRAY_SIZE(uverbs_cmd_table) ||
 	    !uverbs_cmd_table[hdr.command])
 		return -EINVAL;