mm: Split mm parts from task core image

The mm_xxx bits are per-mm_struct, not per-task_struct in kernel.
Thus, when we support CLONE_VM we'd better have these bits in a
separate image file.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-dump.c

@@ -683,20 +683,22 @@ static int dump_task_creds(pid_t pid, const struct parasite_dump_misc *misc,
 #define assign_reg(dst, src, e)		dst.e = (__typeof__(dst.e))src.e
 #define assign_array(dst, src, e)	memcpy(&dst.e, &src.e, sizeof(dst.e))
 
-static int get_task_auxv(pid_t pid, struct core_entry *core)
+static int get_task_auxv(pid_t pid, struct mm_entry *mm)
 {
-	int fd = open_proc(pid, "auxv");
-	int ret, i;
+	int fd, ret, i;
+
+	pr_info("Obtainting task auvx ... ");
 
+	fd = open_proc(pid, "auxv");
 	if (fd < 0)
 		return -1;
 
 	for (i = 0; i < AT_VECTOR_SIZE; i++) {
-		ret = read(fd, &core->tc.mm_saved_auxv[i],
-			   sizeof(core->tc.mm_saved_auxv[0]));
+		ret = read(fd, &mm->mm_saved_auxv[i],
+			   sizeof(mm->mm_saved_auxv[0]));
 		if (ret == 0)
 			break;
-		else if (ret != sizeof(core->tc.mm_saved_auxv[0])) {
+		else if (ret != sizeof(mm->mm_saved_auxv[0])) {
 			ret = -1;
 			pr_perror("Error readind %d's auxv[%d]",
 				  pid, i);
@@ -705,12 +707,36 @@ static int get_task_auxv(pid_t pid, struct core_entry *core)
 	}
 
 	ret = 0;
-
 err:
 	close_safe(&fd);
 	return ret;
 }
 
+static int dump_task_mm(pid_t pid, const struct proc_pid_stat *stat,
+		const struct parasite_dump_misc *misc, const struct cr_fdset *fdset)
+{
+	struct mm_entry mme;
+
+	mme.mm_start_code = stat->start_code;
+	mme.mm_end_code = stat->end_code;
+	mme.mm_start_data = stat->start_data;
+	mme.mm_end_data = stat->end_data;
+	mme.mm_start_stack = stat->start_stack;
+	mme.mm_start_brk = stat->start_brk;
+
+	mme.mm_arg_start = stat->arg_start;
+	mme.mm_arg_end = stat->arg_end;
+	mme.mm_env_start = stat->env_start;
+	mme.mm_env_end = stat->env_end;
+
+	mme.mm_brk = misc->brk;
+
+	if (get_task_auxv(pid, &mme))
+		return -1;
+
+	return write_img(fdset_fd(fdset, CR_FD_MM), &mme);
+}
+
 static int get_task_personality(pid_t pid, u32 *personality)
 {
 	FILE *file = NULL;
@@ -860,29 +886,14 @@ static int dump_task_core_all(pid_t pid, const struct proc_pid_stat *stat,
 
 	strncpy((char *)core->tc.comm, stat->comm, TASK_COMM_LEN);
 	core->tc.flags = stat->flags;
-	core->tc.mm_start_code = stat->start_code;
-	core->tc.mm_end_code = stat->end_code;
-	core->tc.mm_start_data = stat->start_data;
-	core->tc.mm_end_data = stat->end_data;
-	core->tc.mm_start_stack = stat->start_stack;
-	core->tc.mm_start_brk = stat->start_brk;
-
-	core->tc.mm_arg_start = stat->arg_start;
-	core->tc.mm_arg_end = stat->arg_end;
-	core->tc.mm_env_start = stat->env_start;
-	core->tc.mm_env_end = stat->env_end;
 
-	core->tc.mm_brk = misc->brk;
+	ret = dump_task_mm(pid, stat, misc, cr_fdset);
+	if (ret)
+		goto err_free;
 
 	BUILD_BUG_ON(sizeof(core->tc.blk_sigset) != sizeof(k_rtsigset_t));
 	memcpy(&core->tc.blk_sigset, &misc->blocked, sizeof(k_rtsigset_t));
 
-	pr_info("Obtainting task auvx ... ");
-	ret = get_task_auxv(pid, core);
-	if (ret)
-		goto err_free;
-	pr_info("OK\n");
-
 	core->tc.task_state = TASK_ALIVE;
 	core->tc.exit_code = 0;
 

cr-restore.c

@@ -1026,6 +1026,21 @@ static struct vma_entry *vma_list_remap(void *addr, unsigned long len, struct li
 	return ret;
 }
 
+static int prepare_mm(pid_t pid, struct task_restore_core_args *args)
+{
+	int fd;
+
+	fd = open_image_ro(CR_FD_MM, pid);
+	if (fd < 0)
+		return -1;
+
+	if (read_img(fd, &args->mm) < 0)
+		return -1;
+
+	close(fd);
+	return 0;
+}
+
 static int sigreturn_restore(pid_t pid, struct list_head *tgt_vmas, int nr_vmas)
 {
 	long restore_code_len, restore_task_vma_len;
@@ -1205,6 +1220,10 @@ static int sigreturn_restore(pid_t pid, struct list_head *tgt_vmas, int nr_vmas)
 	if (ret < 0)
 		goto err;
 
+	ret = prepare_mm(pid, task_args);
+	if (ret < 0)
+		goto err;
+
 	mutex_init(&task_args->rst_lock);
 
 	/*

cr-show.c

@@ -473,18 +473,7 @@ static void show_core_rest(int fd_core)
 	pr_msg("\t   Exit code: %u\n",
 	       (unsigned int)tc.exit_code);
 
-	pr_msg("\tBrk:          %lx\n", tc.mm_brk);
-	pr_msg("\tStart code:   %lx\n", tc.mm_start_code);
-	pr_msg("\tEnd code:     %lx\n", tc.mm_end_code);
-	pr_msg("\tStart stack:  %lx\n", tc.mm_start_stack);
-	pr_msg("\tStart data:   %lx\n", tc.mm_start_data);
-	pr_msg("\tEnd data:     %lx\n", tc.mm_end_data);
-	pr_msg("\tStart brk:    %lx\n", tc.mm_start_brk);
-	pr_msg("\tArg start:    %lx\n", tc.mm_arg_start);
-	pr_msg("\tArg end:      %lx\n", tc.mm_arg_end);
-	pr_msg("\tEnv start:    %lx\n", tc.mm_env_start);
-	pr_msg("\tEnv end:      %lx\n", tc.mm_env_end);
-	pr_msg("\n\tBlkSig: %lx\n", tc.blk_sigset);
+	pr_msg("\tBlkSig: %lx\n", tc.blk_sigset);
 	pr_msg("\n");
 
 err:
@@ -514,6 +503,30 @@ out:
 	pr_img_tail(CR_FD_CORE);
 }
 
+void show_mm(int fd_mm, struct cr_options *o)
+{
+	struct mm_entry mme;
+
+	pr_img_head(CR_FD_MM);
+
+	if (read_img(fd_mm, &mme) < 0)
+		goto out;
+
+	pr_msg("\tBrk:          %lx\n", mme.mm_brk);
+	pr_msg("\tStart code:   %lx\n", mme.mm_start_code);
+	pr_msg("\tEnd code:     %lx\n", mme.mm_end_code);
+	pr_msg("\tStart stack:  %lx\n", mme.mm_start_stack);
+	pr_msg("\tStart data:   %lx\n", mme.mm_start_data);
+	pr_msg("\tEnd data:     %lx\n", mme.mm_end_data);
+	pr_msg("\tStart brk:    %lx\n", mme.mm_start_brk);
+	pr_msg("\tArg start:    %lx\n", mme.mm_arg_start);
+	pr_msg("\tArg end:      %lx\n", mme.mm_arg_end);
+	pr_msg("\tEnv start:    %lx\n", mme.mm_env_start);
+	pr_msg("\tEnv end:      %lx\n", mme.mm_env_end);
+out:
+	pr_img_tail(CR_FD_MM);
+}
+
 static int cr_parse_file(struct cr_options *opts)
 {
 	u32 magic;

crtools.c

@@ -68,6 +68,12 @@ struct cr_fd_desc_tmpl fdset_template[CR_FD_MAX] = {
 		.show	= show_core,
 	},
 
+	[CR_FD_MM] = {
+		.fmt	= FMT_FNAME_MM,
+		.magic	= MM_MAGIC,
+		.show	= show_mm,
+	},
+
 	[CR_FD_VMAS] = {
 		.fmt	= FMT_FNAME_VMAS,
 		.magic	= VMAS_MAGIC,

include/crtools.h

@@ -22,6 +22,7 @@ enum {
 	CR_FD_FDINFO,
 	CR_FD_PAGES,
 	CR_FD_CORE,
+	CR_FD_MM,
 	CR_FD_VMAS,
 	CR_FD_SIGACT,
 	CR_FD_ITIMERS,
@@ -84,6 +85,7 @@ void show_files(int fd_files, struct cr_options *o);
 void show_pages(int fd_pages, struct cr_options *o);
 void show_reg_files(int fd_reg_files, struct cr_options *o);
 void show_core(int fd_core, struct cr_options *o);
+void show_mm(int fd_mm, struct cr_options *o);
 void show_vmas(int fd_vma, struct cr_options *o);
 void show_pipes(int fd_pipes, struct cr_options *o);
 void show_pipes_data(int fd_pipes, struct cr_options *o);
@@ -100,6 +102,7 @@ extern struct cr_fd_desc_tmpl fdset_template[CR_FD_MAX];
 #define FMT_FNAME_SHMEM_PAGES	"pages-shmem-%ld.img"
 #define FMT_FNAME_REG_FILES	"reg-files.img"
 #define FMT_FNAME_CORE		"core-%d.img"
+#define FMT_FNAME_MM		"mm-%d.img"
 #define FMT_FNAME_VMAS		"vmas-%d.img"
 #define FMT_FNAME_PIPES		"pipes.img"
 #define FMT_FNAME_PIPES_DATA	"pipes-data.img"

include/image.h

@@ -29,6 +29,7 @@
 #define IPCNS_SEM_MAGIC	0x59573019 /* St. Petersburg */
 #define REG_FILES_MAGIC	0x50363636 /* Belgorod */
 #define FS_MAGIC	0x51403912 /* Voronezh */
+#define MM_MAGIC	0x57492820 /* Pskov */
 
 #define PIPEFS_MAGIC	0x50495045
 
@@ -353,21 +354,24 @@ struct task_core_entry {
 	u32				personality;
 	u8				comm[TASK_COMM_LEN];
 	u32				flags;
-	u64				mm_start_code;
-	u64				mm_end_code;
-	u64				mm_start_data;
-	u64				mm_end_data;
-	u64				mm_start_stack;
-	u64				mm_start_brk;
-	u64				mm_brk;
-	u64				mm_arg_start;
-	u64				mm_arg_end;
-	u64				mm_env_start;
-	u64				mm_env_end;
 	u64				blk_sigset;
-	u64				mm_saved_auxv[AT_VECTOR_SIZE];
 };
 
+struct mm_entry {
+	u64	mm_start_code;
+	u64	mm_end_code;
+	u64	mm_start_data;
+	u64	mm_end_data;
+	u64	mm_start_stack;
+	u64	mm_start_brk;
+	u64	mm_brk;
+	u64	mm_arg_start;
+	u64	mm_arg_end;
+	u64	mm_env_start;
+	u64	mm_env_end;
+	u64	mm_saved_auxv[AT_VECTOR_SIZE];
+} __packed;
+
 struct core_entry {
 	union {
 		struct {

include/restorer.h

@@ -84,6 +84,7 @@ struct task_restore_core_args {
 	struct itimerval		itimers[3];
 
 	struct creds_entry		creds;
+	struct mm_entry			mm;
 } __aligned(sizeof(long));
 
 struct pt_regs {

restorer.c

@@ -428,19 +428,20 @@ long restore_task(struct task_restore_core_args *args)
 	 * Tune up the task fields.
 	 */
 	ret |= sys_prctl_safe(PR_SET_NAME, (long)core_entry->tc.comm, 0, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_CODE, (long)core_entry->tc.mm_start_code, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_END_CODE,	(long)core_entry->tc.mm_end_code, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_DATA,	(long)core_entry->tc.mm_start_data, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_END_DATA,	(long)core_entry->tc.mm_end_data, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_STACK,(long)core_entry->tc.mm_start_stack, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_BRK,	(long)core_entry->tc.mm_start_brk, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_BRK,	(long)core_entry->tc.mm_brk, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ARG_START,	(long)core_entry->tc.mm_arg_start, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ARG_END,	(long)core_entry->tc.mm_arg_end, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ENV_START,	(long)core_entry->tc.mm_env_start, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ENV_END,	(long)core_entry->tc.mm_env_end, 0);
-	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_AUXV,	(long)core_entry->tc.mm_saved_auxv,
-								sizeof(core_entry->tc.mm_saved_auxv));
+
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_CODE,	(long)args->mm.mm_start_code, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_END_CODE,	(long)args->mm.mm_end_code, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_DATA,	(long)args->mm.mm_start_data, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_END_DATA,	(long)args->mm.mm_end_data, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_STACK,	(long)args->mm.mm_start_stack, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_BRK,	(long)args->mm.mm_start_brk, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_BRK,		(long)args->mm.mm_brk, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ARG_START,	(long)args->mm.mm_arg_start, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ARG_END,	(long)args->mm.mm_arg_end, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ENV_START,	(long)args->mm.mm_env_start, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ENV_END,	(long)args->mm.mm_env_end, 0);
+	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_AUXV,	(long)args->mm.mm_saved_auxv,
+								sizeof(args->mm.mm_saved_auxv));
 	if (ret)
 		goto core_restore_end;