Initialize for btrfsprogs

2024-02-06 16:32:39 +08:00 · 2024-02-06 16:32:39 +08:00 · bb727004d7
commit bb727004d7
15 changed files with 2860 additions and 0 deletions
--- a/0002-btrfs-progs-Ignore-devices-representing-paths-in-mul.patch
+++ b/0002-btrfs-progs-Ignore-devices-representing-paths-in-mul.patch
@ -0,0 +1,128 @@
+From 39849d97765ed133e0e7ee6eb87ecf5e20eb0d0e Mon Sep 17 00:00:00 2001
+From: Nikolay Borisov <nborisov@suse.com>
+Date: Thu, 30 Sep 2021 15:06:33 +0300
+Subject: [PATCH 2/3] btrfs-progs: Ignore devices representing paths in
+ multipath
+
+Currently btrfs-progs will happily enumerate any device which has a
+btrfs filesystem on it irrespective of its type. For the majority of
+use cases that's fine and there haven't been any problems with that.
+However, there was a recent report that in multipath scenario when
+running "btrfs fi show" after a path flap (path going down and then
+coming back up) instead of the multipath device being show the device
+which represents the flapped path is shown. So a multipath filesystem
+might look like:
+
+Label: none  uuid: d3c1261f-18be-4015-9fef-6b35759dfdba
+        Total devices 1 FS bytes used 192.00KiB
+        devid    1 size 10.00GiB used 536.00MiB path /dev/mapper/3600140501cc1f49e5364f0093869c763
+
+/dev/mapper/xxx is actually backed by an arbitrary number of paths,
+which in turn are presented to the system as ordinary scsi devices i.e
+/dev/sdX. If a path flaps and a user re-runs 'btrfs fi show' the output
+would look like:
+
+Label: none  uuid: d3c1261f-18be-4015-9fef-6b35759dfdba
+        Total devices 1 FS bytes used 192.00KiB
+        devid    1 size 10.00GiB used 536.00MiB path /dev/sdd
+
+This only occurs on unmounted filesystems as those are enumerated by
+btrfs-progs, for mounted filesystem the kernel properly deals only with
+the actual multipath device.
+
+Turns out the output of this command is consumed by libraries and the
+presence of a path device rather than the actual multipath causes
+issues.
+
+Fix this by checking for the presence of DM_MULTIPATH_DEVICE_PATH
+udev attribute as multipath path devices are tagged with this attribute
+by the multipath udev scripts.
+
+Signed-off-by: Nikolay Borisov <nborisov@suse.com>
+---
+ common/device-scan.c | 48 ++++++++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 48 insertions(+)
+
+diff --git a/common/device-scan.c b/common/device-scan.c
+index b5bfe844104b..311673e6b66e 100644
+--- a/common/device-scan.c
+++ b/common/device-scan.c
+@@ -14,6 +14,10 @@
+  * Boston, MA 021110-1307, USA.
+  */
+ 
+#ifdef STATIC_BUILD
+#undef HAVE_LIBUDEV
+#endif
+
+ #include "kerncompat.h"
+ #include <sys/ioctl.h>
+ #include <stdlib.h>
+@@ -39,6 +43,10 @@
+ #include "kernel-shared/zoned.h"
+ #include "ioctl.h"
+ 
+#ifdef HAVE_LIBUDEV
+#include <libudev.h>
+#endif
+
+ static int btrfs_scan_done = 0;
+ 
+ /*
+@@ -364,6 +372,43 @@ void free_seen_fsid(struct seen_fsid *seen_fsid_hash[])
+ 	}
+ }
+ 
+#ifdef HAVE_LIBUDEV
+static bool is_path_device(char *device_path)
+{
+   struct udev *udev = NULL;
+   struct udev_device *dev = NULL;
+   struct stat dev_stat;
+   const char *val;
+   bool ret = false;
+
+   if (stat(device_path, &dev_stat) < 0)
+       return false;
+
+   udev = udev_new();
+   if (!udev)
+       goto out;
+
+   dev = udev_device_new_from_devnum(udev, 'b', dev_stat.st_rdev);
+   if (!dev)
+       goto out;
+
+   val = udev_device_get_property_value(dev, "DM_MULTIPATH_DEVICE_PATH");
+   if (val && atoi(val) > 0)
+       ret = true;
+out:
+   udev_device_unref(dev);
+   udev_unref(udev);
+
+   return ret;
+}
+#else
+static bool is_path_device(char *device_path)
+{
+   return false;
+}
+#endif
+
+
+ int btrfs_scan_devices(int verbose)
+ {
+ 	int fd = -1;
+@@ -394,6 +439,9 @@ int btrfs_scan_devices(int verbose)
+ 		/* if we are here its definitely a btrfs disk*/
+ 		strncpy_null(path, blkid_dev_devname(dev));
+ 
+		if (is_path_device(path))
+			continue;
+
+ 		fd = open(path, O_RDONLY);
+ 		if (fd < 0) {
+ 			error("cannot open %s: %m", path);
+-- 
+2.25.1
+