summaryrefslogtreecommitdiffstats
path: root/fs/ocfs2/dlmglue.h
diff options
context:
space:
mode:
authorwengang wang <wen.gang.wang@oracle.com>2009-03-06 21:29:10 +0800
committerMark Fasheh <mfasheh@suse.com>2009-04-03 11:39:25 -0700
commit6ca497a83e592d64e050c4d04b6dedb8c915f39a (patch)
tree0b9cd611d6d907881841eca73d12a7f3b85f1716 /fs/ocfs2/dlmglue.h
parent9405dccfd3201d2b76e120949bec81ba8cfbd2d0 (diff)
downloadlinux-6ca497a83e592d64e050c4d04b6dedb8c915f39a.tar.gz
linux-6ca497a83e592d64e050c4d04b6dedb8c915f39a.tar.bz2
linux-6ca497a83e592d64e050c4d04b6dedb8c915f39a.zip
ocfs2: fix rare stale inode errors when exporting via nfs
For nfs exporting, ocfs2_get_dentry() returns the dentry for fh. ocfs2_get_dentry() may read from disk when the inode is not in memory, without any cross cluster lock. this leads to the file system loading a stale inode. This patch fixes above problem. Solution is that in case of inode is not in memory, we get the cluster lock(PR) of alloc inode where the inode in question is allocated from (this causes node on which deletion is done sync the alloc inode) before reading out the inode itsself. then we check the bitmap in the group (the inode in question allcated from) to see if the bit is clear. if it's clear then it's stale. if the bit is set, we then check generation as the existing code does. We have to read out the inode in question from disk first to know its alloc slot and allot bit. And if its not stale we read it out using ocfs2_iget(). The second read should then be from cache. And also we have to add a per superblock nfs_sync_lock to cover the lock for alloc inode and that for inode in question. this is because ocfs2_get_dentry() and ocfs2_delete_inode() lock on them in reverse order. nfs_sync_lock is locked in EX mode in ocfs2_get_dentry() and in PR mode in ocfs2_delete_inode(). so that mutliple ocfs2_delete_inode() can run concurrently in normal case. [mfasheh@suse.com: build warning fixes and comment cleanups] Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com> Acked-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Diffstat (limited to 'fs/ocfs2/dlmglue.h')
-rw-r--r--fs/ocfs2/dlmglue.h2
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/ocfs2/dlmglue.h b/fs/ocfs2/dlmglue.h
index 3f8d9986b8e0..e1fd5721cd7f 100644
--- a/fs/ocfs2/dlmglue.h
+++ b/fs/ocfs2/dlmglue.h
@@ -115,6 +115,8 @@ void ocfs2_super_unlock(struct ocfs2_super *osb,
int ex);
int ocfs2_rename_lock(struct ocfs2_super *osb);
void ocfs2_rename_unlock(struct ocfs2_super *osb);
+int ocfs2_nfs_sync_lock(struct ocfs2_super *osb, int ex);
+void ocfs2_nfs_sync_unlock(struct ocfs2_super *osb, int ex);
int ocfs2_dentry_lock(struct dentry *dentry, int ex);
void ocfs2_dentry_unlock(struct dentry *dentry, int ex);
int ocfs2_file_lock(struct file *file, int ex, int trylock);