[CRIU] [PATCH v4 17/17] mount: create target directory for AutoFS indirect mounts.

[Stanislav Kinsburskiy]

In case of mounting AutoFS indirect mount points, target dentry doesn't exist
and has to be created.

Signed-off-by: Stanislav Kinsburskiy <skinsbursky at virtuozzo.com>
---
 autofs.c         |   11 +++++++++++
 include/autofs.h |    1 +
 mount.c          |   13 +++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/autofs.c b/autofs.c
index c5e4556..46c585e 100644
--- a/autofs.c
+++ b/autofs.c
@@ -807,3 +807,14 @@ umount:
 	goto close_pipe;
 }
 
+bool autofs_indirect_mount(struct mount_info *mi)
+{
+	struct mount_info *parent = mi->parent;
+
+	if (strcmp(parent->fstype->name, "autofs"))
+		return false;
+
+	BUG_ON(parent->autofs == NULL);
+
+	return parent->autofs->mode != AUTOFS_MODE_DIRECT;
+}
diff --git a/include/autofs.h b/include/autofs.h
index 0a63c98..b522b2f 100644
--- a/include/autofs.h
+++ b/include/autofs.h
@@ -12,6 +12,7 @@ int autofs_parse(struct mount_info *pm, bool for_dump);
 int autofs_dump(struct mount_info *pm);
 int autofs_mount(struct mount_info *mi, const char *source, const
 		 char *filesystemtype, unsigned long mountflags);
+bool autofs_indirect_mount(struct mount_info *mi);
 
 #include <linux/auto_fs.h>
 
diff --git a/mount.c b/mount.c
index 40c20ea..a30121d 100644
--- a/mount.c
+++ b/mount.c
@@ -2242,6 +2242,19 @@ static int do_new_mount(struct mount_info *mi)
 	if (remount_ro)
 		sflags &= ~MS_RDONLY;
 
+	if (autofs_indirect_mount(mi)) {
+		/*
+		 * We have to create mount target manually.
+		 */
+		pr_info("Creating autofs indirect mount dentry: %s (%d)\n",
+				mi->mountpoint, getpid());
+		if (mkdir(mi->mountpoint, 0555) < 0) {
+			pr_perror("Failed to create autofs dentry %s",
+					mi->mountpoint);
+			return -1;
+		}
+	}
+
 	if (do_mount(mi, src, tp->name, sflags) < 0) {
 		pr_perror("Can't mount at %s", mi->mountpoint);
 		return -1;