On 2021/4/20 20:51, Jeff Layton wrote:
On Tue, 2021-04-20 at 10:02 +0800, Xiubo Li wrote:
On 2021/4/20 0:09, Jeff Layton wrote:
On Mon, 2021-04-19 at 10:32 +0800, xiubli@xxxxxxxxxx wrote:
From: Xiubo Li <xiubli@xxxxxxxxxx>
Inode number 0x4 is reserved for the lost+found dir, and the app
or test app need to access it.
URL: https://tracker.ceph.com/issues/50216
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
---
fs/ceph/super.h | 3 ++-
include/linux/ceph/ceph_fs.h | 7 ++++---
2 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 4808a1458c9b..0f38e6183ff0 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -542,7 +542,8 @@ static inline int ceph_ino_compare(struct inode *inode, void *data)
static inline bool ceph_vino_is_reserved(const struct ceph_vino vino)
{
- if (vino.ino < CEPH_INO_SYSTEM_BASE && vino.ino != CEPH_INO_ROOT) {
+ if (vino.ino < CEPH_INO_SYSTEM_BASE && vino.ino != CEPH_INO_ROOT &&
+ vino.ino != CEPH_INO_LOST_AND_FOUND ) {
WARN_RATELIMIT(1, "Attempt to access reserved inode number 0x%llx", vino.ino);
return true;
}
diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h
index e41a811026f6..57e5bd63fb7a 100644
--- a/include/linux/ceph/ceph_fs.h
+++ b/include/linux/ceph/ceph_fs.h
@@ -27,9 +27,10 @@
#define CEPH_MONC_PROTOCOL 15 /* server/client */
-#define CEPH_INO_ROOT 1
-#define CEPH_INO_CEPH 2 /* hidden .ceph dir */
-#define CEPH_INO_DOTDOT 3 /* used by ceph fuse for parent (..) */
Hi Jeff,
Please fix the "CEPH_INO_DOTDOT" when you folding this patch. The inode
number 3 is not _DOTDOT any more. This was introduced by an very old
commit(dd6f5e105d85e) but I couldn't find the related change about this
in ceph code.
It should be:
#define CEPH_INO_GLOBAL_SNAPREALM 3
Sounds good. I can fold that change into the patch.
What should we use for a comment there? I took a look at the MDS code
and it wasn't clear to me what the global_snaprealm is actually for...
Maybe the commit comment title is a good choice from Zheng's initial commit:
commit 0f31d49de20bd40836dceebb06e12763a1def5e0
Author: Yan, Zheng <ukernel@xxxxxxxxx>
Date: Thu Oct 26 15:32:29 2017 +0800
mds: attach inode with multiple hardlinks to dummy global snaprealm
The dummy global snaprealm includes all snapshots in the filesystem.
For any later snapshot, mds will COW the inode and preserve snap data.
These snap data will cover any possible snapshot on remote linkages
of the inode.
+#define CEPH_INO_ROOT 1
+#define CEPH_INO_CEPH 2 /* hidden .ceph dir */
+#define CEPH_INO_DOTDOT 3 /* used by ceph fuse for parent (..) */
+#define CEPH_INO_LOST_AND_FOUND 4 /* lost+found dir */
/* arbitrary limit on max # of monitors (cluster of 3 is typical) */
#define CEPH_MAX_MON 31
Thanks Xiubo,
For some background, apparently cephfs-data-scan can create this
directory, and the clients do need access to it. I'll fold this into the
original patch that makes these inodes inaccessible (ceph: don't allow
access to MDS-private inodes).
Cheers!
