From: Amir Goldstein <amir73il@gmail.com>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: linux-unionfs@vger.kernel.org
Subject: [PATCH 1/2] ovl: remove the 'locked' argument of ovl_nlink_{start,end}
Date: Thu, 18 Oct 2018 18:37:13 +0300 [thread overview]
Message-ID: <20181018153714.3834-2-amir73il@gmail.com> (raw)
In-Reply-To: <20181018153714.3834-1-amir73il@gmail.com>
It just makes the interface strange without adding any significant value.
The only case where locked is false and return value is 0 is in
ovl_rename() when new is negative, so handle that case explicitly in
ovl_rename().
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
fs/overlayfs/dir.c | 21 +++++++++++----------
fs/overlayfs/overlayfs.h | 4 ++--
fs/overlayfs/util.c | 28 ++++++++++++----------------
3 files changed, 25 insertions(+), 28 deletions(-)
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index e1a55ecb7aba..e03f39550ccf 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -652,7 +652,6 @@ static int ovl_link(struct dentry *old, struct inode *newdir,
struct dentry *new)
{
int err;
- bool locked = false;
struct inode *inode;
err = ovl_want_write(old);
@@ -673,7 +672,7 @@ static int ovl_link(struct dentry *old, struct inode *newdir,
goto out_drop_write;
}
- err = ovl_nlink_start(old, &locked);
+ err = ovl_nlink_start(old);
if (err)
goto out_drop_write;
@@ -686,7 +685,7 @@ static int ovl_link(struct dentry *old, struct inode *newdir,
if (err)
iput(inode);
- ovl_nlink_end(old, locked);
+ ovl_nlink_end(old);
out_drop_write:
ovl_drop_write(old);
out:
@@ -811,7 +810,6 @@ static bool ovl_pure_upper(struct dentry *dentry)
static int ovl_do_remove(struct dentry *dentry, bool is_dir)
{
int err;
- bool locked = false;
const struct cred *old_cred;
struct dentry *upperdentry;
bool lower_positive = ovl_lower_positive(dentry);
@@ -832,7 +830,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir)
if (err)
goto out_drop_write;
- err = ovl_nlink_start(dentry, &locked);
+ err = ovl_nlink_start(dentry);
if (err)
goto out_drop_write;
@@ -848,7 +846,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir)
else
drop_nlink(dentry->d_inode);
}
- ovl_nlink_end(dentry, locked);
+ ovl_nlink_end(dentry);
/*
* Copy ctime
@@ -1012,7 +1010,6 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
unsigned int flags)
{
int err;
- bool locked = false;
struct dentry *old_upperdir;
struct dentry *new_upperdir;
struct dentry *olddentry;
@@ -1021,6 +1018,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
bool old_opaque;
bool new_opaque;
bool cleanup_whiteout = false;
+ bool update_nlink = false;
bool overwrite = !(flags & RENAME_EXCHANGE);
bool is_dir = d_is_dir(old);
bool new_is_dir = d_is_dir(new);
@@ -1078,10 +1076,12 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
err = ovl_copy_up(new);
if (err)
goto out_drop_write;
- } else {
- err = ovl_nlink_start(new, &locked);
+ } else if (d_inode(new)) {
+ err = ovl_nlink_start(new);
if (err)
goto out_drop_write;
+
+ update_nlink = true;
}
old_cred = ovl_override_creds(old->d_sb);
@@ -1210,7 +1210,8 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
unlock_rename(new_upperdir, old_upperdir);
out_revert_creds:
revert_creds(old_cred);
- ovl_nlink_end(new, locked);
+ if (update_nlink)
+ ovl_nlink_end(new);
out_drop_write:
ovl_drop_write(old);
out:
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index a3c0d9584312..b48ef22ef96b 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -271,8 +271,8 @@ bool ovl_test_flag(unsigned long flag, struct inode *inode);
bool ovl_inuse_trylock(struct dentry *dentry);
void ovl_inuse_unlock(struct dentry *dentry);
bool ovl_need_index(struct dentry *dentry);
-int ovl_nlink_start(struct dentry *dentry, bool *locked);
-void ovl_nlink_end(struct dentry *dentry, bool locked);
+int ovl_nlink_start(struct dentry *dentry);
+void ovl_nlink_end(struct dentry *dentry);
int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir);
int ovl_check_metacopy_xattr(struct dentry *dentry);
bool ovl_is_metacopy_dentry(struct dentry *dentry);
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 8cd37baf5d0a..d3a786006729 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -738,14 +738,14 @@ static void ovl_cleanup_index(struct dentry *dentry)
* Operations that change overlay inode and upper inode nlink need to be
* synchronized with copy up for persistent nlink accounting.
*/
-int ovl_nlink_start(struct dentry *dentry, bool *locked)
+int ovl_nlink_start(struct dentry *dentry)
{
struct ovl_inode *oi = OVL_I(d_inode(dentry));
const struct cred *old_cred;
int err;
- if (!d_inode(dentry))
- return 0;
+ if (WARN_ON(!d_inode(dentry)))
+ return -ENOENT;
/*
* With inodes index is enabled, we store the union overlay nlink
@@ -787,26 +787,22 @@ int ovl_nlink_start(struct dentry *dentry, bool *locked)
out:
if (err)
mutex_unlock(&oi->lock);
- else
- *locked = true;
return err;
}
-void ovl_nlink_end(struct dentry *dentry, bool locked)
+void ovl_nlink_end(struct dentry *dentry)
{
- if (locked) {
- if (ovl_test_flag(OVL_INDEX, d_inode(dentry)) &&
- d_inode(dentry)->i_nlink == 0) {
- const struct cred *old_cred;
-
- old_cred = ovl_override_creds(dentry->d_sb);
- ovl_cleanup_index(dentry);
- revert_creds(old_cred);
- }
+ if (ovl_test_flag(OVL_INDEX, d_inode(dentry)) &&
+ d_inode(dentry)->i_nlink == 0) {
+ const struct cred *old_cred;
- mutex_unlock(&OVL_I(d_inode(dentry))->lock);
+ old_cred = ovl_override_creds(dentry->d_sb);
+ ovl_cleanup_index(dentry);
+ revert_creds(old_cred);
}
+
+ mutex_unlock(&OVL_I(d_inode(dentry))->lock);
}
int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)
--
2.17.1
next prev parent reply other threads:[~2018-10-18 15:37 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-18 15:37 [PATCH 0/2] Overlay inode lock cleanups Amir Goldstein
2018-10-18 15:37 ` Amir Goldstein [this message]
2018-10-18 15:37 ` [PATCH 2/2] ovl: abstract ovl_inode lock with a helper Amir Goldstein
2018-10-26 21:55 ` [PATCH 0/2] Overlay inode lock cleanups Miklos Szeredi
2018-10-29 20:38 ` Amir Goldstein
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