refactor process_msg_prepare_process() in preparation for execve()

kernel/host.c

@@ -50,71 +50,38 @@ void check_mapping_for_proc(struct process *proc, unsigned long addr)
 }
 
 /* 
- * Communication with host 
+ * Prepares the process ranges based on the ELF header described 
+ * in program_load_desc and updates physical address in "p" so that
+ * host can copy program image.
+ * It also prepares args, envs and the process stack.
+ * 
+ * NOTE: if args, args_len, envs, envs_len are zero, 
+ * the function constructs them based on the descriptor 
  */
-static int process_msg_prepare_process(unsigned long rphys)
+int prepare_process_ranges_args_envs(struct process *proc, 
+		struct program_load_desc *pn,
+		struct program_load_desc *p,
+		enum ihk_mc_pt_attribute attr,
+		char *args, int args_len,
+		char *envs, int envs_len) 
 {
-	unsigned long phys, sz, s, e, up;
-	struct program_load_desc *p, *pn;
-	int i, npages, n;
-	struct process *proc;
-	unsigned long addr;
 	char *args_envs, *args_envs_r;
 	unsigned long args_envs_p, args_envs_rp;
+	unsigned long s, e, up;
 	char **argv;
-	int argc, envc, args_envs_npages;
+	int i, n, argc, envc, args_envs_npages;
 	char **env;
 	int range_npages;
 	void *up_v;
+	unsigned long addr;
 	unsigned long flags;
 	uintptr_t interp_obase = -1;
 	uintptr_t interp_nbase = -1;
-	enum ihk_mc_pt_attribute attr;
-
-	attr = PTATTR_NO_EXECUTE | PTATTR_WRITABLE | PTATTR_FOR_USER;
-
-	sz = sizeof(struct program_load_desc)
-		+ sizeof(struct program_image_section) * 16;
-	npages = ((rphys + sz - 1) >> PAGE_SHIFT) - (rphys >> PAGE_SHIFT) + 1;
-
-	phys = ihk_mc_map_memory(NULL, rphys, sz);
-	if((p = ihk_mc_map_virtual(phys, npages, attr)) == NULL){
-		ihk_mc_unmap_memory(NULL, phys, sz);
-		return -ENOMEM;
-	}
 	
 	n = p->num_sections;
-	dkprintf("# of sections: %d\n", n);
-
-	if((pn = ihk_mc_allocate(sizeof(struct program_load_desc) 
-	       + sizeof(struct program_image_section) * n, IHK_MC_AP_NOWAIT)) == NULL){
-		ihk_mc_unmap_virtual(p, npages, 0);
-		ihk_mc_unmap_memory(NULL, phys, sz);
-		return -ENOMEM;
-	}
-	memcpy_long(pn, p, sizeof(struct program_load_desc) 
-	            + sizeof(struct program_image_section) * n);
-
-	if((proc = create_process(p->entry)) == NULL){
-		ihk_mc_free(pn);
-		ihk_mc_unmap_virtual(p, npages, 1);
-		ihk_mc_unmap_memory(NULL, phys, sz);
-		return -ENOMEM;
-	}
-	proc->pid = pn->pid;
-	proc->tid = pn->pid;
-	proc->ftn->pid = pn->pid;
-	proc->vm->region.user_start = pn->user_start;
-	proc->vm->region.user_end = pn->user_end;
-	proc->vm->region.map_start = (USER_END / 3) & LARGE_PAGE_MASK;
-	proc->vm->region.map_end = proc->vm->region.map_start;
-	proc->rlimit_stack.rlim_cur = pn->rlimit_stack_cur;
-	proc->rlimit_stack.rlim_max = pn->rlimit_stack_max;
-
-	/* TODO: Clear it at the proper timing */
-	cpu_local_var(scp).post_idx = 0;
 
 	for (i = 0; i < n; i++) {
+		
 		if (pn->sections[i].interp && (interp_nbase == (uintptr_t)-1)) {
 			interp_obase = pn->sections[i].vaddr;
 			interp_obase -= (interp_obase % pn->interp_align);
@@ -122,6 +89,7 @@ static int process_msg_prepare_process(unsigned long rphys)
 			interp_nbase = (interp_nbase + pn->interp_align - 1)
 				& ~(pn->interp_align - 1);
 		}
+
 		if (pn->sections[i].interp) {
 			pn->sections[i].vaddr -= interp_obase;
 			pn->sections[i].vaddr += interp_nbase;
@@ -135,9 +103,11 @@ static int process_msg_prepare_process(unsigned long rphys)
 		flags |= PROT_TO_VR_FLAG(pn->sections[i].prot);
 		flags |= VRFLAG_PROT_TO_MAXPROT(flags);
 
-			if((up_v = ihk_mc_alloc_pages(range_npages, IHK_MC_AP_NOWAIT)) == NULL){
+		if ((up_v = ihk_mc_alloc_pages(range_npages, IHK_MC_AP_NOWAIT)) 
+				== NULL) {
 			goto err;
 		} 
+		
 		up = virt_to_phys(up_v);
 		if (add_process_memory_range(proc, s, e, up, flags, NULL, 0) != 0) {
 			ihk_mc_free_pages(up_v, range_npages);
@@ -178,10 +148,12 @@ static int process_msg_prepare_process(unsigned long rphys)
 		else if (i == 0) {
 			proc->vm->region.text_start = s;
 			proc->vm->region.text_end = e;
-		} else if (i == 1) {
+		} 
+		else if (i == 1) {
 			proc->vm->region.data_start = s;
 			proc->vm->region.data_end = e;
-		} else {
+		} 
+		else {
 			proc->vm->region.data_start =
 				(s < proc->vm->region.data_start ? 
 				 s : proc->vm->region.data_start);
@@ -195,7 +167,8 @@ static int process_msg_prepare_process(unsigned long rphys)
 		pn->entry -= interp_obase;
 		pn->entry += interp_nbase;
 		p->entry = pn->entry;
-		ihk_mc_modify_user_context(proc->uctx, IHK_UCR_PROGRAM_COUNTER, pn->entry);
+		ihk_mc_modify_user_context(proc->uctx, IHK_UCR_PROGRAM_COUNTER, 
+				pn->entry);
 	}
 
 #if 1
@@ -331,10 +304,78 @@ static int process_msg_prepare_process(unsigned long rphys)
 
 	p->rprocess = (unsigned long)proc;
 	p->rpgtable = virt_to_phys(proc->vm->page_table);
+	
 	if (init_process_stack(proc, pn, argc, argv, envc, env) != 0) {
 		goto err;
 	}
 
+	return 0;
+
+err:
+	/* TODO: cleanup allocated ranges */
+	return -1;
+}
+
+/*
+ * Communication with host 
+ */
+static int process_msg_prepare_process(unsigned long rphys)
+{
+	unsigned long phys, sz;
+	struct program_load_desc *p, *pn;
+	int npages, n;
+	struct process *proc;
+	enum ihk_mc_pt_attribute attr;
+
+	attr = PTATTR_NO_EXECUTE | PTATTR_WRITABLE | PTATTR_FOR_USER;
+
+	sz = sizeof(struct program_load_desc)
+		+ sizeof(struct program_image_section) * 16;
+	npages = ((rphys + sz - 1) >> PAGE_SHIFT) - (rphys >> PAGE_SHIFT) + 1;
+
+	phys = ihk_mc_map_memory(NULL, rphys, sz);
+	if((p = ihk_mc_map_virtual(phys, npages, attr)) == NULL){
+		ihk_mc_unmap_memory(NULL, phys, sz);
+		return -ENOMEM;
+	}
+
+	n = p->num_sections;
+	dkprintf("# of sections: %d\n", n);
+
+	if((pn = ihk_mc_allocate(sizeof(struct program_load_desc) 
+	       + sizeof(struct program_image_section) * n, IHK_MC_AP_NOWAIT)) == NULL){
+		ihk_mc_unmap_virtual(p, npages, 0);
+		ihk_mc_unmap_memory(NULL, phys, sz);
+		return -ENOMEM;
+	}
+	memcpy_long(pn, p, sizeof(struct program_load_desc) 
+	            + sizeof(struct program_image_section) * n);
+
+	if((proc = create_process(p->entry)) == NULL){
+		ihk_mc_free(pn);
+		ihk_mc_unmap_virtual(p, npages, 1);
+		ihk_mc_unmap_memory(NULL, phys, sz);
+		return -ENOMEM;
+	}
+	proc->pid = pn->pid;
+	proc->tid = pn->pid;
+	proc->ftn->pid = pn->pid;
+	proc->vm->region.user_start = pn->user_start;
+	proc->vm->region.user_end = pn->user_end;
+	proc->vm->region.map_start = (USER_END / 3) & LARGE_PAGE_MASK;
+	proc->vm->region.map_end = proc->vm->region.map_start;
+	proc->rlimit_stack.rlim_cur = pn->rlimit_stack_cur;
+	proc->rlimit_stack.rlim_max = pn->rlimit_stack_max;
+
+	/* TODO: Clear it at the proper timing */
+	cpu_local_var(scp).post_idx = 0;
+
+	if (prepare_process_ranges_args_envs(proc, pn, p, attr, 
+				NULL, 0, NULL, 0) != 0) {
+		kprintf("error: preparing process ranges, args, envs, stack\n");
+		goto err;
+	}
+
 	dkprintf("new process : %p [%d] / table : %p\n", proc, proc->pid,
 	        proc->vm->page_table);