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Date: Tue, 29 Jul 2008 22:43:34 -0400
From: Erez Zadok <ezk@...sunysb.edu>
To: akpm@...ux-foundation.org
Cc: linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
viro@...iv.linux.org.uk, hch@...radead.org, miklos@...redi.hu,
Erez Zadok <ezk@...sunysb.edu>
Subject: [PATCH 04/19] Unionfs: create and consolidate helpers to iput lower objects
Signed-off-by: Erez Zadok <ezk@...sunysb.edu>
---
fs/unionfs/commonfops.c | 5 +---
fs/unionfs/copyup.c | 5 +--
fs/unionfs/dentry.c | 25 +-----------------------
fs/unionfs/fanout.h | 49 +++++++++++++++++++++++++++++++++++++++++++++++
fs/unionfs/super.c | 6 +----
fs/unionfs/unlink.c | 22 ++------------------
6 files changed, 57 insertions(+), 55 deletions(-)
diff --git a/fs/unionfs/commonfops.c b/fs/unionfs/commonfops.c
index 6f61fb0..585c5c9 100644
--- a/fs/unionfs/commonfops.c
+++ b/fs/unionfs/commonfops.c
@@ -280,14 +280,11 @@ static int do_delayed_copyup(struct file *file)
unionfs_set_lower_mnt_idx(dentry, bindex, NULL);
}
if (unionfs_lower_dentry_idx(dentry, bindex)) {
- BUG_ON(!dentry->d_inode);
- iput(unionfs_lower_inode_idx(dentry->d_inode, bindex));
- unionfs_set_lower_inode_idx(dentry->d_inode, bindex,
- NULL);
dput(unionfs_lower_dentry_idx(dentry, bindex));
unionfs_set_lower_dentry_idx(dentry, bindex, NULL);
}
}
+ iput_lowers(dentry->d_inode, bstart, bend, false);
/* for reg file, we only open it "once" */
fbend(file) = fbstart(file);
dbend(dentry) = dbstart(dentry);
diff --git a/fs/unionfs/copyup.c b/fs/unionfs/copyup.c
index b918897..f20b984 100644
--- a/fs/unionfs/copyup.c
+++ b/fs/unionfs/copyup.c
@@ -877,11 +877,10 @@ void unionfs_postcopyup_release(struct dentry *dentry)
if (unionfs_lower_dentry_idx(dentry, bindex)) {
dput(unionfs_lower_dentry_idx(dentry, bindex));
unionfs_set_lower_dentry_idx(dentry, bindex, NULL);
- iput(unionfs_lower_inode_idx(dentry->d_inode, bindex));
- unionfs_set_lower_inode_idx(dentry->d_inode, bindex,
- NULL);
}
}
+ iput_lowers(dentry->d_inode, dbstart(dentry)+1, dbend(dentry), false);
+
bindex = dbstart(dentry);
dbend(dentry) = bindex;
ibend(dentry->d_inode) = ibstart(dentry->d_inode) = bindex;
diff --git a/fs/unionfs/dentry.c b/fs/unionfs/dentry.c
index 44b17ce..a7960ac 100644
--- a/fs/unionfs/dentry.c
+++ b/fs/unionfs/dentry.c
@@ -35,22 +35,6 @@ static inline void __dput_lowers(struct dentry *dentry, int start, int end)
}
}
-static inline void __iput_lowers(struct inode *inode, int start, int end)
-{
- struct inode *lower_inode;
- int bindex;
-
- if (start < 0)
- return;
- for (bindex = start; bindex <= end; bindex++) {
- lower_inode = unionfs_lower_inode_idx(inode, bindex);
- if (!lower_inode)
- continue;
- unionfs_set_lower_inode_idx(inode, bindex, NULL);
- iput(lower_inode);
- }
-}
-
/*
* Revalidate a single dentry.
* Assume that dentry's info node is locked.
@@ -111,14 +95,7 @@ static bool __unionfs_d_revalidate_one(struct dentry *dentry,
interpose_flag = INTERPOSE_REVAL_NEG;
if (positive) {
interpose_flag = INTERPOSE_REVAL;
-
- bstart = ibstart(dentry->d_inode);
- bend = ibend(dentry->d_inode);
- __iput_lowers(dentry->d_inode, bstart, bend);
- kfree(UNIONFS_I(dentry->d_inode)->lower_inodes);
- UNIONFS_I(dentry->d_inode)->lower_inodes = NULL;
- ibstart(dentry->d_inode) = -1;
- ibend(dentry->d_inode) = -1;
+ iput_lowers_all(dentry->d_inode, true);
}
result = unionfs_lookup_backend(dentry, &lowernd,
diff --git a/fs/unionfs/fanout.h b/fs/unionfs/fanout.h
index 69a8e8f..94421f8 100644
--- a/fs/unionfs/fanout.h
+++ b/fs/unionfs/fanout.h
@@ -277,4 +277,53 @@ static inline void verify_locked(struct dentry *d)
BUG_ON(!mutex_is_locked(&UNIONFS_D(d)->lock));
}
+/* macros to put lower objects */
+
+/*
+ * iput lower inodes of an unionfs dentry, from bstart to bend. If
+ * @free_lower is true, then also kfree the memory used to hold the lower
+ * object pointers.
+ */
+static inline void iput_lowers(struct inode *inode,
+ int bstart, int bend, bool free_lower)
+{
+ struct inode *lower_inode;
+ int bindex;
+
+ BUG_ON(!inode);
+ BUG_ON(!UNIONFS_I(inode));
+ BUG_ON(bstart < 0);
+
+ for (bindex = bstart; bindex <= bend; bindex++) {
+ lower_inode = unionfs_lower_inode_idx(inode, bindex);
+ if (lower_inode) {
+ unionfs_set_lower_inode_idx(inode, bindex, NULL);
+ /* see Documentation/filesystems/unionfs/issues.txt */
+ lockdep_off();
+ iput(lower_inode);
+ lockdep_on();
+ }
+ }
+
+ if (free_lower) {
+ kfree(UNIONFS_I(inode)->lower_inodes);
+ UNIONFS_I(inode)->lower_inodes = NULL;
+ }
+}
+
+/* iput all lower inodes, and reset start/end branch indices to -1 */
+static inline void iput_lowers_all(struct inode *inode, bool free_lower)
+{
+ int bstart, bend;
+
+ BUG_ON(!inode);
+ BUG_ON(!UNIONFS_I(inode));
+ bstart = ibstart(inode);
+ bend = ibend(inode);
+ BUG_ON(bstart < 0);
+
+ iput_lowers(inode, bstart, bend, free_lower);
+ ibstart(inode) = ibend(inode) = -1;
+}
+
#endif /* not _FANOUT_H */
diff --git a/fs/unionfs/super.c b/fs/unionfs/super.c
index 1a172af..9715529 100644
--- a/fs/unionfs/super.c
+++ b/fs/unionfs/super.c
@@ -789,11 +789,7 @@ out_no_change:
new_lower_inodes[i] = lower_dentry->d_inode;
}
/* 2. release reference on all older lower inodes */
- for (i = old_ibstart; i <= old_ibend; i++) {
- iput(unionfs_lower_inode_idx(sb->s_root->d_inode, i));
- unionfs_set_lower_inode_idx(sb->s_root->d_inode, i, NULL);
- }
- kfree(UNIONFS_I(sb->s_root->d_inode)->lower_inodes);
+ iput_lowers(sb->s_root->d_inode, old_ibstart, old_ibend, true);
/* 3. update root dentry's inode to new lower_inodes array */
UNIONFS_I(sb->s_root->d_inode)->lower_inodes = new_lower_inodes;
new_lower_inodes = NULL;
diff --git a/fs/unionfs/unlink.c b/fs/unionfs/unlink.c
index cad0386..3d6ca5f 100644
--- a/fs/unionfs/unlink.c
+++ b/fs/unionfs/unlink.c
@@ -146,12 +146,8 @@ int unionfs_unlink(struct inode *dir, struct dentry *dentry)
/* call d_drop so the system "forgets" about us */
if (!err) {
unionfs_postcopyup_release(dentry);
- if (inode->i_nlink == 0) {
- /* drop lower inodes */
- iput(unionfs_lower_inode(inode));
- unionfs_set_lower_inode(inode, NULL);
- ibstart(inode) = ibend(inode) = -1;
- }
+ if (inode->i_nlink == 0) /* drop lower inodes */
+ iput_lowers_all(inode, false);
d_drop(dentry);
/*
* if unlink/whiteout succeeded, parent dir mtime has
@@ -264,21 +260,9 @@ out:
* about us.
*/
if (!err) {
- struct inode *inode = dentry->d_inode;
- BUG_ON(!inode);
- iput(unionfs_lower_inode_idx(inode, dstart));
- unionfs_set_lower_inode_idx(inode, dstart, NULL);
+ iput_lowers_all(dentry->d_inode, false);
dput(unionfs_lower_dentry_idx(dentry, dstart));
unionfs_set_lower_dentry_idx(dentry, dstart, NULL);
- /*
- * If the last directory is unlinked, then mark istart/end
- * as -1, (to maintain the invariant that if there are no
- * lower objects, then branch index start and end are set to
- * -1).
- */
- if (!unionfs_lower_inode_idx(inode, dstart) &&
- !unionfs_lower_inode_idx(inode, dend))
- ibstart(inode) = ibend(inode) = -1;
d_drop(dentry);
/* update our lower vfsmnts, in case a copyup took place */
unionfs_postcopyup_setmnt(dentry);
--
1.5.2.2
--
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