diff options
author | Brian Behlendorf <[email protected]> | 2016-11-07 10:28:57 -0800 |
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committer | GitHub <[email protected]> | 2016-11-07 10:28:57 -0800 |
commit | 83bf769d500a231eac023c9f9f88719ad205694e (patch) | |
tree | e919e807bd61476a759c4d54d5d566d25dc3e9e6 /include | |
parent | 34328f3cf8a4ca9441a1609878500ef1ff2eeb16 (diff) |
Fix 'zpool import' detection issues
This patch addresses multiple 'zpool import' block device
indentification problems which are most likely to occur on a
system configured to use blkid, by_vdev paths, multipath and
failover. The symptom most commonly observed is the import
uses different path names to import the pool than would
normally be expected.
* When using blkid to identify vdevs the listed devices may
be added to the cache in any order. In order to apply the
preferred search order heuristic a zfs_path_order() function
was added to calculate the order given full path names.
* Since it's possible to have multiple block devices with
different vdev guids which refer to the same ZPOOL_CONFIG_PATH
the slice cache must be indexed by guid and name. By avoiding
collisions the preferred ordering can be maintaining even
when multiple block devices claim the same ZPOOL_CONFIG_PATH.
The preferred sorting by partition was never benefitial for
a Linux system and was removed as part of this change.
* When adding entries to the blkid cache avl_find/avl_insert
are used instead of avl_add because collisions are possible
and must be handled gracefully.
* For pools using multipath devices there are, at a minimum,
three devices where a vdev label may be read. They are the
dm-* device and each underlying /dev/sd* device. Due to the
way the block cache is implemented each of these devices may
have a different cached copy of the vdev label. This can
result in "ghost pools" which appear to persist even after
a 'zpool labelclear' has been done to the dm-* device. In
order to prevent this the vdev label is read with O_DIRECT
in order to bypass any caching to get the on-disk version.
* When opening a block device verify that vdev guid read from
the disk matches the expected vdev guid. This allows for bad
labels to be filtered out.
Reviewed-by: Tony Hutter <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #5359
Diffstat (limited to 'include')
-rw-r--r-- | include/libzfs.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/libzfs.h b/include/libzfs.h index d4962dec6..5744ce87a 100644 --- a/include/libzfs.h +++ b/include/libzfs.h @@ -64,6 +64,10 @@ extern "C" { */ #define DISK_LABEL_WAIT (30 * 1000) /* 30 seconds */ +#define IMPORT_ORDER_PREFERRED_1 1 +#define IMPORT_ORDER_PREFERRED_2 2 +#define IMPORT_ORDER_SCAN_OFFSET 10 +#define IMPORT_ORDER_DEFAULT 100 #define DEFAULT_IMPORT_PATH_SIZE 9 extern char *zpool_default_import_path[DEFAULT_IMPORT_PATH_SIZE]; @@ -728,6 +732,7 @@ extern boolean_t zfs_bookmark_exists(const char *path); extern int zfs_append_partition(char *path, size_t max_len); extern int zfs_resolve_shortname(const char *name, char *path, size_t pathlen); extern int zfs_strcmp_pathname(char *name, char *cmp_name, int wholedisk); +extern int zfs_path_order(char *path, int *order); /* * Mount support functions. |