[PATCH v3 04/06] 9p fid refcount: add p9_fid_get/put wrappers

Dominique Martinet
2022-06-15T03:17:51Z

I was recently reminded that it is not clear that p9_client_clunk()
was actually just decrementing refcount and clunking only when that
reaches zero: make it clear through a set of helpers.

This will also allow instrumenting refcounting better for debugging
next patch

Link: https://lkml.kernel.org/r/20220612085330.1451496-5-asmadeus@codewreck.org
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
---
v1 -> v2: p9_fid_get/put are now static inline in .h
v2 -> v3: fix commit message and add comment to helpers

fs/9p/fid.c | 18 ++++++++--------
fs/9p/fid.h | 2 +-
fs/9p/vfs_addr.c | 4 ++--
fs/9p/vfs_dentry.c | 4 ++--
fs/9p/vfs_dir.c | 2 +-
fs/9p/vfs_file.c | 4 ++--
fs/9p/vfs_inode.c | 48 ++++++++++++++++++++---------------------
fs/9p/vfs_inode_dotl.c | 42 ++++++++++++++++++------------------
fs/9p/vfs_super.c | 6 +++---
fs/9p/xattr.c | 8 +++----
include/net/9p/client.h | 28 ++++++++++++++++++++++++
net/9p/client.c | 15 +++----------
12 files changed, 100 insertions(+), 81 deletions(-)

diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index e8fad28fc5bd..d792499349c4 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -56,7 +56,7 @@ static struct p9_fid *v9fs_fid_find_inode(struct inode *inode, kuid_t uid)
h = (struct hlist_head *)&inode->i_private;
hlist_for_each_entry(fid, h, ilist) {
if (uid_eq(fid->uid, uid)) {
- refcount_inc(&fid->count);
+ p9_fid_get(fid);
ret = fid;
break;
}
@@ -104,7 +104,7 @@ static struct p9_fid *v9fs_fid_find(struct dentry *dentry, kuid_t uid, int any)
hlist_for_each_entry(fid, h, dlist) {
if (any || uid_eq(fid->uid, uid)) {
ret = fid;
- refcount_inc(&ret->count);
+ p9_fid_get(ret);
break;
}
}
@@ -172,7 +172,7 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
old_fid = fid;

fid = p9_client_walk(old_fid, 1, &dentry->d_name.name, 1);
- p9_client_clunk(old_fid);
+ p9_fid_put(old_fid);
goto fid_out;
}
up_read(&v9ses->rename_sem);
@@ -194,7 +194,7 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
if (IS_ERR(root_fid))
return root_fid;

- refcount_inc(&root_fid->count);
+ p9_fid_get(root_fid);
v9fs_fid_add(dentry->d_sb->s_root, root_fid);
}
/* If we are root ourself just return that */
@@ -225,7 +225,7 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
old_fid == root_fid /* clone */);
/* non-cloning walk will return the same fid */
if (fid != old_fid) {
- p9_client_clunk(old_fid);
+ p9_fid_put(old_fid);
old_fid = fid;
}
if (IS_ERR(fid)) {
@@ -240,11 +240,11 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
spin_lock(&dentry->d_lock);
if (d_unhashed(dentry)) {
spin_unlock(&dentry->d_lock);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
fid = ERR_PTR(-ENOENT);
} else {
__add_fid(dentry, fid);
- refcount_inc(&fid->count);
+ p9_fid_get(fid);
spin_unlock(&dentry->d_lock);
}
}
@@ -301,7 +301,7 @@ struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
fid = clone_fid(ofid);
if (IS_ERR(fid))
goto error_out;
- p9_client_clunk(ofid);
+ p9_fid_put(ofid);
/*
* writeback fid will only be used to write back the
* dirty pages. We always request for the open fid in read-write
@@ -310,7 +310,7 @@ struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
*/
err = p9_client_open(fid, O_RDWR);
if (err < 0) {
- p9_client_clunk(fid);
+ p9_fid_put(fid);
fid = ERR_PTR(err);
goto error_out;
}
diff --git a/fs/9p/fid.h b/fs/9p/fid.h
index f7f33509e169..3168dfad510e 100644
--- a/fs/9p/fid.h
+++ b/fs/9p/fid.h
@@ -29,7 +29,7 @@ static inline struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
return fid;

nfid = clone_fid(fid);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
return nfid;
}
#endif
diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c
index 7f924e671e3e..c5f71eeb28b6 100644
--- a/fs/9p/vfs_addr.c
+++ b/fs/9p/vfs_addr.c
@@ -70,7 +70,7 @@ static int v9fs_init_request(struct netfs_io_request *rreq, struct file *file)

BUG_ON(!fid);

- refcount_inc(&fid->count);
+ p9_fid_get(fid);
rreq->netfs_priv = fid;
return 0;
}
@@ -83,7 +83,7 @@ static void v9fs_free_request(struct netfs_io_request *rreq)
{
struct p9_fid *fid = rreq->netfs_priv;

- p9_client_clunk(fid);
+ p9_fid_put(fid);
}

/**
diff --git a/fs/9p/vfs_dentry.c b/fs/9p/vfs_dentry.c
index 1c609e99d280..f89f01734587 100644
--- a/fs/9p/vfs_dentry.c
+++ b/fs/9p/vfs_dentry.c
@@ -54,7 +54,7 @@ static void v9fs_dentry_release(struct dentry *dentry)
p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
dentry, dentry);
hlist_for_each_safe(p, n, (struct hlist_head *)&dentry->d_fsdata)
- p9_client_clunk(hlist_entry(p, struct p9_fid, dlist));
+ p9_fid_put(hlist_entry(p, struct p9_fid, dlist));
dentry->d_fsdata = NULL;
}

@@ -85,7 +85,7 @@ static int v9fs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
retval = v9fs_refresh_inode_dotl(fid, inode);
else
retval = v9fs_refresh_inode(fid, inode);
- p9_client_clunk(fid);
+ p9_fid_put(fid);

if (retval == -ENOENT)
return 0;
diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
index 958680f7f23e..000fbaae9b18 100644
--- a/fs/9p/vfs_dir.c
+++ b/fs/9p/vfs_dir.c
@@ -218,7 +218,7 @@ int v9fs_dir_release(struct inode *inode, struct file *filp)
spin_lock(&inode->i_lock);
hlist_del(&fid->ilist);
spin_unlock(&inode->i_lock);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
}

if ((filp->f_mode & FMODE_WRITE)) {
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 2573c08f335c..8276f3af35d7 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -63,7 +63,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)

err = p9_client_open(fid, omode);
if (err < 0) {
- p9_client_clunk(fid);
+ p9_fid_put(fid);
return err;
}
if ((file->f_flags & O_APPEND) &&
@@ -98,7 +98,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)
v9fs_open_fid_add(inode, fid);
return 0;
out_error:
- p9_client_clunk(file->private_data);
+ p9_fid_put(file->private_data);
file->private_data = NULL;
return err;
}
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 3d8297714772..bde18776f0c7 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -400,7 +400,7 @@ void v9fs_evict_inode(struct inode *inode)
fscache_relinquish_cookie(v9fs_inode_cookie(v9inode), false);
/* clunk the fid stashed in writeback_fid */
if (v9inode->writeback_fid) {
- p9_client_clunk(v9inode->writeback_fid);
+ p9_fid_put(v9inode->writeback_fid);
v9inode->writeback_fid = NULL;
}
}
@@ -569,7 +569,7 @@ static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags)
if (v9fs_proto_dotl(v9ses))
retval = p9_client_unlinkat(dfid, dentry->d_name.name,
v9fs_at_to_dotl_flags(flags));
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
if (retval == -EOPNOTSUPP) {
/* Try the one based on path */
v9fid = v9fs_fid_clone(dentry);
@@ -633,14 +633,14 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
if (IS_ERR(ofid)) {
err = PTR_ERR(ofid);
p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
return ERR_PTR(err);
}

err = p9_client_fcreate(ofid, name, perm, mode, extension);
if (err < 0) {
p9_debug(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
goto error;
}

@@ -652,7 +652,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
p9_debug(P9_DEBUG_VFS,
"p9_client_walk failed %d\n", err);
fid = NULL;
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
goto error;
}
/*
@@ -663,20 +663,20 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
err = PTR_ERR(inode);
p9_debug(P9_DEBUG_VFS,
"inode creation failed %d\n", err);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
goto error;
}
v9fs_fid_add(dentry, fid);
d_instantiate(dentry, inode);
}
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
return ofid;
error:
if (ofid)
- p9_client_clunk(ofid);
+ p9_fid_put(ofid);

if (fid)
- p9_client_clunk(fid);
+ p9_fid_put(fid);

return ERR_PTR(err);
}
@@ -708,7 +708,7 @@ v9fs_vfs_create(struct user_namespace *mnt_userns, struct inode *dir,
return PTR_ERR(fid);

v9fs_invalidate_inode_attr(dir);
- p9_client_clunk(fid);
+ p9_fid_put(fid);

return 0;
}
@@ -744,7 +744,7 @@ static int v9fs_vfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
}

if (fid)
- p9_client_clunk(fid);
+ p9_fid_put(fid);

return err;
}
@@ -785,7 +785,7 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
*/
name = dentry->d_name.name;
fid = p9_client_walk(dfid, 1, &name, 1);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
if (fid == ERR_PTR(-ENOENT))
inode = NULL;
else if (IS_ERR(fid))
@@ -808,7 +808,7 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
else if (!IS_ERR(res))
v9fs_fid_add(res, fid);
else
- p9_client_clunk(fid);
+ p9_fid_put(fid);
}
return res;
}
@@ -891,7 +891,7 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,

error:
if (fid)
- p9_client_clunk(fid);
+ p9_fid_put(fid);
goto out;
}

@@ -959,7 +959,7 @@ v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
dfid = v9fs_parent_fid(old_dentry);
olddirfid = clone_fid(dfid);
if (dfid && !IS_ERR(dfid))
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);

if (IS_ERR(olddirfid)) {
retval = PTR_ERR(olddirfid);
@@ -968,7 +968,7 @@ v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,

dfid = v9fs_parent_fid(new_dentry);
newdirfid = clone_fid(dfid);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);

if (IS_ERR(newdirfid)) {
retval = PTR_ERR(newdirfid);
@@ -1020,13 +1020,13 @@ v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
d_move(old_dentry, new_dentry);
}
up_write(&v9ses->rename_sem);
- p9_client_clunk(newdirfid);
+ p9_fid_put(newdirfid);

clunk_olddir:
- p9_client_clunk(olddirfid);
+ p9_fid_put(olddirfid);

done:
- p9_client_clunk(oldfid);
+ p9_fid_put(oldfid);
return retval;
}

@@ -1060,7 +1060,7 @@ v9fs_vfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
return PTR_ERR(fid);

st = p9_client_stat(fid);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
if (IS_ERR(st))
return PTR_ERR(st);

@@ -1136,7 +1136,7 @@ static int v9fs_vfs_setattr(struct user_namespace *mnt_userns,
retval = p9_client_wstat(fid, &wstat);

if (use_dentry)
- p9_client_clunk(fid);
+ p9_fid_put(fid);

if (retval < 0)
return retval;
@@ -1261,7 +1261,7 @@ static const char *v9fs_vfs_get_link(struct dentry *dentry,
return ERR_CAST(fid);

st = p9_client_stat(fid);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
if (IS_ERR(st))
return ERR_CAST(st);

@@ -1308,7 +1308,7 @@ static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
return PTR_ERR(fid);

v9fs_invalidate_inode_attr(dir);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
return 0;
}

@@ -1364,7 +1364,7 @@ v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
v9fs_refresh_inode(oldfid, d_inode(old_dentry));
v9fs_invalidate_inode_attr(dir);
}
- p9_client_clunk(oldfid);
+ p9_fid_put(oldfid);
return retval;
}

diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index b6eb1160296c..09b124fe349c 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -274,7 +274,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
if (IS_ERR(ofid)) {
err = PTR_ERR(ofid);
p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
goto out;
}

@@ -286,7 +286,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
if (err) {
p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
err);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
goto error;
}
err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
@@ -294,14 +294,14 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
if (err < 0) {
p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
err);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
goto error;
}
v9fs_invalidate_inode_attr(dir);

/* instantiate inode and assign the unopened fid to the dentry */
fid = p9_client_walk(dfid, 1, &name, 1);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
if (IS_ERR(fid)) {
err = PTR_ERR(fid);
p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
@@ -358,10 +358,10 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,

error:
if (fid)
- p9_client_clunk(fid);
+ p9_fid_put(fid);
err_clunk_old_fid:
if (ofid)
- p9_client_clunk(ofid);
+ p9_fid_put(ofid);
goto out;
}

@@ -458,9 +458,9 @@ static int v9fs_vfs_mkdir_dotl(struct user_namespace *mnt_userns,
v9fs_invalidate_inode_attr(dir);
error:
if (fid)
- p9_client_clunk(fid);
+ p9_fid_put(fid);
v9fs_put_acl(dacl, pacl);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
return err;
}

@@ -489,7 +489,7 @@ v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns,
*/

st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
if (IS_ERR(st))
return PTR_ERR(st);

@@ -603,7 +603,7 @@ int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns,
retval = p9_client_setattr(fid, &p9attr);
if (retval < 0) {
if (use_dentry)
- p9_client_clunk(fid);
+ p9_fid_put(fid);
return retval;
}

@@ -619,12 +619,12 @@ int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns,
retval = v9fs_acl_chmod(inode, fid);
if (retval < 0) {
if (use_dentry)
- p9_client_clunk(fid);
+ p9_fid_put(fid);
return retval;
}
}
if (use_dentry)
- p9_client_clunk(fid);
+ p9_fid_put(fid);

return 0;
}
@@ -771,9 +771,9 @@ v9fs_vfs_symlink_dotl(struct user_namespace *mnt_userns, struct inode *dir,

error:
if (fid)
- p9_client_clunk(fid);
+ p9_fid_put(fid);

- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
return err;
}

@@ -803,14 +803,14 @@ v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,

oldfid = v9fs_fid_lookup(old_dentry);
if (IS_ERR(oldfid)) {
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);
return PTR_ERR(oldfid);
}

err = p9_client_link(dfid, oldfid, dentry->d_name.name);

- p9_client_clunk(dfid);
- p9_client_clunk(oldfid);
+ p9_fid_put(dfid);
+ p9_fid_put(oldfid);
if (err < 0) {
p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
return err;
@@ -826,7 +826,7 @@ v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
return PTR_ERR(fid);

v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
- p9_client_clunk(fid);
+ p9_fid_put(fid);
}
ihold(d_inode(old_dentry));
d_instantiate(dentry, d_inode(old_dentry));
@@ -924,9 +924,9 @@ v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
}
error:
if (fid)
- p9_client_clunk(fid);
+ p9_fid_put(fid);
v9fs_put_acl(dacl, pacl);
- p9_client_clunk(dfid);
+ p9_fid_put(dfid);

return err;
}
@@ -956,7 +956,7 @@ v9fs_vfs_get_link_dotl(struct dentry *dentry,
if (IS_ERR(fid))
return ERR_CAST(fid);
retval = p9_client_readlink(fid, &target);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
if (retval)
return ERR_PTR(retval);
set_delayed_call(done, kfree_link, target);
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index 97e23b4e6982..bf350fad9500 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -190,7 +190,7 @@ static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
return dget(sb->s_root);

clunk_fid:
- p9_client_clunk(fid);
+ p9_fid_put(fid);
v9fs_session_close(v9ses);
free_session:
kfree(v9ses);
@@ -203,7 +203,7 @@ static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
* attached the fid to dentry so it won't get clunked
* automatically.
*/
- p9_client_clunk(fid);
+ p9_fid_put(fid);
deactivate_locked_super(sb);
return ERR_PTR(retval);
}
@@ -270,7 +270,7 @@ static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
}
res = simple_statfs(dentry, buf);
done:
- p9_client_clunk(fid);
+ p9_fid_put(fid);
return res;
}

diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index a824441b95a2..1f9298a4bd42 100644
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -44,7 +44,7 @@ ssize_t v9fs_fid_xattr_get(struct p9_fid *fid, const char *name,
if (err)
retval = err;
}
- p9_client_clunk(attr_fid);
+ p9_fid_put(attr_fid);
return retval;
}

@@ -71,7 +71,7 @@ ssize_t v9fs_xattr_get(struct dentry *dentry, const char *name,
if (IS_ERR(fid))
return PTR_ERR(fid);
ret = v9fs_fid_xattr_get(fid, name, buffer, buffer_size);
- p9_client_clunk(fid);
+ p9_fid_put(fid);

return ret;
}
@@ -98,7 +98,7 @@ int v9fs_xattr_set(struct dentry *dentry, const char *name,
if (IS_ERR(fid))
return PTR_ERR(fid);
ret = v9fs_fid_xattr_set(fid, name, value, value_len, flags);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
return ret;
}

@@ -128,7 +128,7 @@ int v9fs_fid_xattr_set(struct p9_fid *fid, const char *name,
retval);
else
p9_client_write(fid, 0, &from, &retval);
- err = p9_client_clunk(fid);
+ err = p9_fid_put(fid);
if (!retval && err)
retval = err;
return retval;
diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index ec1d1706f43c..eabb53992350 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -237,6 +237,34 @@ static inline int p9_req_try_get(struct p9_req_t *r)

int p9_req_put(struct p9_req_t *r);

+/* fid reference counting helpers:
+ * - fids used for any length of time should always be referenced through
+ * p9_fid_get(), and released with p9_fid_put()
+ * - v9fs_fid_lookup() or similar will automatically call get for you
+ * and also require a put
+ * - the *_fid_add() helpers will stash the fid in the inode,
+ * at which point it is the responsibility of evict_inode()
+ * to call the put
+ * - the last put will automatically send a clunk to the server
+ */
+static inline struct p9_fid *p9_fid_get(struct p9_fid *fid)
+{
+ refcount_inc(&fid->count);
+
+ return fid;
+}
+
+static inline int p9_fid_put(struct p9_fid *fid)
+{
+ if (!fid || IS_ERR(fid))
+ return 0;
+
+ if (!refcount_dec_and_test(&fid->count))
+ return 0;
+
+ return p9_client_clunk(fid);
+}
+
void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status);

int p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type,
diff --git a/net/9p/client.c b/net/9p/client.c
index 8bba0d9cf975..f3eb280c7d9d 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -1228,7 +1228,7 @@ struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,

clunk_fid:
kfree(wqids);
- p9_client_clunk(fid);
+ p9_fid_put(fid);
fid = NULL;

error:
@@ -1459,15 +1459,6 @@ int p9_client_clunk(struct p9_fid *fid)
struct p9_req_t *req;
int retries = 0;

- if (!fid || IS_ERR(fid)) {
- pr_warn("%s (%d): Trying to clunk with invalid fid\n",
- __func__, task_pid_nr(current));
- dump_stack();
- return 0;
- }
- if (!refcount_dec_and_test(&fid->count))
- return 0;
-
again:
p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n",
fid->fid, retries);
@@ -1519,7 +1510,7 @@ int p9_client_remove(struct p9_fid *fid)
p9_tag_remove(clnt, req);
error:
if (err == -ERESTARTSYS)
- p9_client_clunk(fid);
+ p9_fid_put(fid);
else
p9_fid_destroy(fid);
return err;
@@ -2042,7 +2033,7 @@ struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
attr_fid->fid, *attr_size);
return attr_fid;
clunk_fid:
- p9_client_clunk(attr_fid);
+ p9_fid_put(attr_fid);
attr_fid = NULL;
error:
if (attr_fid && attr_fid != file_fid)
--
2.35.1