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Message-Id: <11887860561137-git-send-email-jsipek@cs.sunysb.edu>
Date: Sun, 2 Sep 2007 22:20:28 -0400
From: "Josef 'Jeff' Sipek" <jsipek@...sunysb.edu>
To: akpm@...ux-foundation.org
Cc: linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
hch@...radead.org, viro@....linux.org.uk,
bharata@...ux.vnet.ibm.com, j.blunck@...harburg.de,
Erez Zadok <ezk@...sunysb.edu>,
"Josef 'Jeff' Sipek" <jsipek@...sunysb.edu>
Subject: [PATCH 05/32] Unionfs: do not use fsstack_copy_attr_all
From: Erez Zadok <ezk@...sunysb.edu>
Unionfs needs a special fan-out version of fsstack_copy_attr_all, which is
called unionfs_copy_attr_all.
Signed-off-by: Erez Zadok <ezk@...sunysb.edu>
Signed-off-by: Josef 'Jeff' Sipek <jsipek@...sunysb.edu>
---
fs/unionfs/dentry.c | 12 +++++++++---
fs/unionfs/fanout.h | 50 +++++++++++++++++++++++++++++++++++++++++++++++++-
fs/unionfs/inode.c | 13 ++++++++-----
fs/unionfs/main.c | 2 +-
fs/unionfs/subr.c | 2 +-
fs/unionfs/union.h | 5 +++--
6 files changed, 71 insertions(+), 13 deletions(-)
diff --git a/fs/unionfs/dentry.c b/fs/unionfs/dentry.c
index f88a285..4a3c479 100644
--- a/fs/unionfs/dentry.c
+++ b/fs/unionfs/dentry.c
@@ -166,9 +166,15 @@ static int __unionfs_d_revalidate_one(struct dentry *dentry,
valid = 0;
if (valid) {
- fsstack_copy_attr_all(dentry->d_inode,
- unionfs_lower_inode(dentry->d_inode),
- unionfs_get_nlinks);
+ /*
+ * If we get here, and we copy the meta-data from the lower
+ * inode to our inode, then it is vital that we have already
+ * purged all unionfs-level file data. We do that in the
+ * caller (__unionfs_d_revalidate_chain) by calling
+ * purge_inode_data.
+ */
+ unionfs_copy_attr_all(dentry->d_inode,
+ unionfs_lower_inode(dentry->d_inode));
fsstack_copy_inode_size(dentry->d_inode,
unionfs_lower_inode(dentry->d_inode));
}
diff --git a/fs/unionfs/fanout.h b/fs/unionfs/fanout.h
index 4da34c6..5908bc7 100644
--- a/fs/unionfs/fanout.h
+++ b/fs/unionfs/fanout.h
@@ -305,4 +305,52 @@ static inline void verify_locked(struct dentry *d)
BUG_ON(!mutex_is_locked(&UNIONFS_D(d)->lock));
}
-#endif /* _FANOUT_H */
+/* copy a/m/ctime from the lower branch with the newest times */
+static inline void unionfs_copy_attr_times(struct inode *upper)
+{
+ int bindex;
+ struct inode *lower;
+
+ if (!upper)
+ return;
+ for (bindex=ibstart(upper); bindex <= ibend(upper); bindex++) {
+ lower = unionfs_lower_inode_idx(upper, bindex);
+ if (!lower)
+ continue; /* not all lower dir objects may exist */
+ if (timespec_compare(&upper->i_mtime, &lower->i_mtime) < 0)
+ upper->i_mtime = lower->i_mtime;
+ if (timespec_compare(&upper->i_ctime, &lower->i_ctime) < 0)
+ upper->i_ctime = lower->i_ctime;
+ if (timespec_compare(&upper->i_atime, &lower->i_atime) < 0)
+ upper->i_atime = lower->i_atime;
+ /* XXX: should we notify_change on our upper inode? */
+ }
+}
+
+/*
+ * A unionfs/fanout version of fsstack_copy_attr_all. Uses a
+ * unionfs_get_nlinks to properly calcluate the number of links to a file.
+ * Also, copies the max() of all a/m/ctimes for all lower inodes (which is
+ * important if the lower inode is a directory type)
+ */
+static inline void unionfs_copy_attr_all(struct inode *dest,
+ const struct inode *src)
+{
+ dest->i_mode = src->i_mode;
+ dest->i_uid = src->i_uid;
+ dest->i_gid = src->i_gid;
+ dest->i_rdev = src->i_rdev;
+
+ unionfs_copy_attr_times(dest);
+
+ dest->i_blkbits = src->i_blkbits;
+ dest->i_flags = src->i_flags;
+
+ /*
+ * Update the nlinks AFTER updating the above fields, because the
+ * get_links callback may depend on them.
+ */
+ dest->i_nlink = unionfs_get_nlinks(dest);
+}
+
+#endif /* not _FANOUT_H */
diff --git a/fs/unionfs/inode.c b/fs/unionfs/inode.c
index 59bb418..cbbde6f 100644
--- a/fs/unionfs/inode.c
+++ b/fs/unionfs/inode.c
@@ -369,12 +369,13 @@ check_link:
/* Its a hard link, so use the same inode */
new_dentry->d_inode = igrab(old_dentry->d_inode);
d_instantiate(new_dentry, new_dentry->d_inode);
- fsstack_copy_attr_all(dir, lower_new_dentry->d_parent->d_inode,
- unionfs_get_nlinks);
+ unionfs_copy_attr_all(dir, lower_new_dentry->d_parent->d_inode);
fsstack_copy_inode_size(dir, lower_new_dentry->d_parent->d_inode);
/* propagate number of hard-links */
old_dentry->d_inode->i_nlink = unionfs_get_nlinks(old_dentry->d_inode);
+ /* new dentry's ctime may have changed due to hard-link counts */
+ unionfs_copy_attr_times(new_dentry->d_inode);
out:
if (!new_dentry->d_inode)
@@ -1084,13 +1085,15 @@ static int unionfs_setattr(struct dentry *dentry, struct iattr *ia)
}
/* get the size from the first lower inode */
- lower_inode = unionfs_lower_inode(dentry->d_inode);
- fsstack_copy_attr_all(inode, lower_inode, unionfs_get_nlinks);
+ lower_inode = unionfs_lower_inode(inode);
+ unionfs_copy_attr_all(inode, lower_inode);
fsstack_copy_inode_size(inode, lower_inode);
-
+ /* if setattr succeeded, then parent dir may have changed */
+ unionfs_copy_attr_times(dentry->d_parent->d_inode);
out:
unionfs_unlock_dentry(dentry);
unionfs_read_unlock(dentry->d_sb);
+
return err;
}
diff --git a/fs/unionfs/main.c b/fs/unionfs/main.c
index 1ea7894..689a8fa 100644
--- a/fs/unionfs/main.c
+++ b/fs/unionfs/main.c
@@ -123,7 +123,7 @@ int unionfs_interpose(struct dentry *dentry, struct super_block *sb, int flag)
lower_inode->i_rdev);
/* all well, copy inode attributes */
- fsstack_copy_attr_all(inode, lower_inode, unionfs_get_nlinks);
+ unionfs_copy_attr_all(inode, lower_inode);
fsstack_copy_inode_size(inode, lower_inode);
skip:
diff --git a/fs/unionfs/subr.c b/fs/unionfs/subr.c
index 0c8b0aa..3cebc17 100644
--- a/fs/unionfs/subr.c
+++ b/fs/unionfs/subr.c
@@ -179,7 +179,7 @@ out:
* returns the sum of the n_link values of all the underlying inodes of the
* passed inode
*/
-int unionfs_get_nlinks(struct inode *inode)
+int unionfs_get_nlinks(const struct inode *inode)
{
int sum_nlinks = 0;
int dirs = 0;
diff --git a/fs/unionfs/union.h b/fs/unionfs/union.h
index e4ee3c1..2a8f763 100644
--- a/fs/unionfs/union.h
+++ b/fs/unionfs/union.h
@@ -186,6 +186,9 @@ struct unionfs_dir_state {
struct list_head list[0];
};
+/* externs needed for fanout.h or sioq.h */
+extern int unionfs_get_nlinks(const struct inode *inode);
+
/* include miscellaneous macros */
#include "fanout.h"
#include "sioq.h"
@@ -282,8 +285,6 @@ extern int remove_whiteouts(struct dentry *dentry,
extern int do_delete_whiteouts(struct dentry *dentry, int bindex,
struct unionfs_dir_state *namelist);
-extern int unionfs_get_nlinks(struct inode *inode);
-
/* Is this directory empty: 0 if it is empty, -ENOTEMPTY if not. */
extern int check_empty(struct dentry *dentry,
struct unionfs_dir_state **namelist);
--
1.5.2.2.238.g7cbf2f2
-
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