[7/7] btrfs-progs: refactor check_where_mounted with noscan argument

Commit Message

Anand Jain June 8, 2023, 6:01 a.m. UTC

The function check_where_mounted() scans the system for all other btrfs
devices, which is necessary for its operation.

However, in certain cases, devices remained in the scanned state is
undesirable.

So introduces the 'noscan' argument to make devices unscanned before
return.

Signed-off-by: Anand Jain <[e-mail]>
---
 common/open-utils.c | 9 ++++++---
 common/open-utils.h | 3 ++-
 common/utils.c      | 3 ++-
 tune/main.c         | 2 +-
 4 files changed, 11 insertions(+), 6 deletions(-)

Patch

diff --git a/common/open-utils.c b/common/open-utils.c
index 1e18fa905b51..e34abee97f60 100644
--- a/common/open-utils.c
+++ b/common/open-utils.c
@@ -53,7 +53,8 @@  static int blk_file_in_dev_list(struct btrfs_fs_devices* fs_devices,
 }
 
 int check_mounted_where(int fd, const char *file, char *where, int size,
-			struct btrfs_fs_devices **fs_dev_ret, unsigned sbflags)
+			struct btrfs_fs_devices **fs_dev_ret, unsigned sbflags,
+			bool noscan)
 {
 	struct btrfs_fs_devices *fs_devices_mnt = NULL;
 	struct mntent *mnt;
@@ -108,6 +109,8 @@  int check_mounted_where(int fd, const char *file, char *where, int size,
 	}
 	if (fs_dev_ret)
 		*fs_dev_ret = fs_devices_mnt;
+	else if (noscan)
+		btrfs_close_all_devices();
 
 	ret = (mnt != NULL);
 
@@ -132,7 +135,7 @@  int check_mounted(const char* file)
 		return -errno;
 	}
 
-	ret =  check_mounted_where(fd, file, NULL, 0, NULL, SBREAD_DEFAULT);
+	ret =  check_mounted_where(fd, file, NULL, 0, NULL, SBREAD_DEFAULT, false);
 	close(fd);
 
 	return ret;
@@ -168,7 +171,7 @@  int get_btrfs_mount(const char *dev, char *mp, size_t mp_size)
 		goto out;
 	}
 
-	ret = check_mounted_where(fd, dev, mp, mp_size, NULL, SBREAD_DEFAULT);
+	ret = check_mounted_where(fd, dev, mp, mp_size, NULL, SBREAD_DEFAULT, false);
 	if (!ret) {
 		ret = -EINVAL;
 	} else { /* mounted, all good */
diff --git a/common/open-utils.h b/common/open-utils.h
index 3924be36e2ea..27000cdbd626 100644
--- a/common/open-utils.h
+++ b/common/open-utils.h
@@ -23,7 +23,8 @@ 
 struct btrfs_fs_devices;
 
 int check_mounted_where(int fd, const char *file, char *where, int size,
-			struct btrfs_fs_devices **fs_dev_ret, unsigned sbflags);
+			struct btrfs_fs_devices **fs_dev_ret, unsigned sbflags,
+			bool noscan);
 int check_mounted(const char* file);
 int get_btrfs_mount(const char *dev, char *mp, size_t mp_size);
 int open_path_or_dev_mnt(const char *path, DIR **dirstream, int verbose);
diff --git a/common/utils.c b/common/utils.c
index 436ff8c2a827..b62f9f04ad5a 100644
--- a/common/utils.c
+++ b/common/utils.c
@@ -230,7 +230,8 @@  int get_fs_info(const char *path, struct btrfs_ioctl_fs_info_args *fi_args,
 			goto out;
 		}
 		ret = check_mounted_where(fd, path, mp, sizeof(mp),
-					  &fs_devices_mnt, SBREAD_DEFAULT);
+					  &fs_devices_mnt, SBREAD_DEFAULT,
+					  false);
 		if (!ret) {
 			ret = -EINVAL;
 			goto out;
diff --git a/tune/main.c b/tune/main.c
index e38c1f6d3729..0ca1e01282c9 100644
--- a/tune/main.c
+++ b/tune/main.c
@@ -268,7 +268,7 @@  int BOX_MAIN(btrfstune)(int argc, char *argv[])
 	}
 
 	ret = check_mounted_where(fd, device, NULL, 0, NULL,
-			SBREAD_IGNORE_FSID_MISMATCH);
+				  SBREAD_IGNORE_FSID_MISMATCH, false);
 	if (ret < 0) {
 		errno = -ret;
 		error("could not check mount status of %s: %m", device);