mcexec: --enable-hfi1 to runtime enable/disable HFI1 driver

Conflicts:
	executer/user/mcexec.c

kernel/host.c

@@ -479,6 +479,7 @@ static int process_msg_prepare_process(unsigned long rphys)
 	proc->sgid = pn->cred[6];
 	proc->fsgid = pn->cred[7];
 	proc->termsig = SIGCHLD;
+	proc->mcexec_flags = pn->mcexec_flags;
 	proc->mpol_flags = pn->mpol_flags;
 	proc->mpol_threshold = pn->mpol_threshold;
 	proc->nr_processes = pn->nr_processes;

kernel/include/process.h

@@ -552,6 +552,7 @@ struct process {
 
 	long maxrss;
 	long maxrss_children;
+	unsigned long mcexec_flags;
 	/* Memory policy flags and memory specific options */
 	unsigned long mpol_flags;
 	size_t mpol_threshold;

kernel/include/syscall.h

@@ -166,6 +166,8 @@ typedef unsigned long __cpu_set_unit;
 #define MPOL_NO_BSS               0x04
 #define MPOL_SHM_PREMAP           0x08
 
+#define MCEXEC_HFI1               0x01
+
 struct program_load_desc {
 	int num_sections;
 	int status;
@@ -194,6 +196,7 @@ struct program_load_desc {
 	unsigned long envs_len;
 	struct rlimit rlimit[MCK_RLIM_MAX];
 	unsigned long interp_align;
+	unsigned long mcexec_flags;
 	unsigned long mpol_flags;
 	unsigned long mpol_threshold;
 	unsigned long heap_extension;

kernel/syscall.c

@@ -481,7 +481,8 @@ long do_syscall(struct syscall_request *req, int cpu, int pid)
 #endif // PROFILE_ENABLE
 
 	if (req->number == __NR_open && rc > 0) {
-		if (res.private_data &&
+		if ((cpu_local_var(current)->proc->mcexec_flags & MCEXEC_HFI1) &&
+				res.private_data &&
 				!strncmp((const char *)req->args[0], "/dev/hfi", 8)) {
 			extern void hfi1_txreq_prealloc(void);