Commit dc0325b0 authored by Paulo Alcantara's avatar Paulo Alcantara Committed by Steve French
Browse files

smb: client: get rid of d_drop()+d_add() 



Replace d_drop()+d_add() in cifs_tmpfile() and cifs_create() with
d_instantiate(), and in cifs_atomic_open() with d_splice_alias() if
in-lookup, otherwise d_instantiate().

Reported-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Closes: https://lore.kernel.org/r/20260408065719.GF3836593@ZenIV


Signed-off-by: default avatarPaulo Alcantara (Red Hat) <pc@manguebit.org>
Cc: David Howells <dhowells@redhat.com>
Cc: NeilBrown <neilb@ownmail.net>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 62e02084

fs/smb/client/cifsfs.h

+2 −2
Original line number Diff line number Diff line
@@ -52,9 +52,9 @@ void cifs_sb_deactive(struct super_block *sb); 
/* Functions related to inodes */

extern const struct inode_operations cifs_dir_inode_ops;

struct inode *cifs_root_iget(struct super_block *sb);

int cifs_create(struct mnt_idmap *idmap, struct inode *inode,

int cifs_create(struct mnt_idmap *idmap, struct inode *dir,

		struct dentry *direntry, umode_t mode, bool excl);

int cifs_atomic_open(struct inode *inode, struct dentry *direntry,

int cifs_atomic_open(struct inode *dir, struct dentry *direntry,

		     struct file *file, unsigned int oflags, umode_t mode);

int cifs_tmpfile(struct mnt_idmap *idmap, struct inode *dir,

		 struct file *file, umode_t mode);

fs/smb/client/dir.c

+38 −24
Original line number Diff line number Diff line
@@ -219,6 +219,7 @@ static int __cifs_do_create(struct inode *dir, struct dentry *direntry, 
	int rdwr_for_fscache = 0;

	__le32 lease_flags = 0;



	*inode = NULL;

	*oplock = 0;

	if (tcon->ses->server->oplocks)

		*oplock = REQ_OPLOCK;
@@ -462,7 +463,6 @@ static int __cifs_do_create(struct inode *dir, struct dentry *direntry, 
		goto out_err;

	}



	d_drop(direntry);

	*inode = newinode;

	return rc;
@@ -478,11 +478,11 @@ static int cifs_do_create(struct inode *dir, struct dentry *direntry, 
			  unsigned int xid, struct tcon_link *tlink,

			  unsigned int oflags, umode_t mode,

			  __u32 *oplock, struct cifs_fid *fid,

			  struct cifs_open_info_data *buf)

			  struct cifs_open_info_data *buf,

			  struct inode **inode)

{

	void *page = alloc_dentry_path();

	const char *full_path;

	struct inode *inode;

	int rc;



	full_path = build_path_from_dentry(direntry, page);
@@ -491,9 +491,7 @@ static int cifs_do_create(struct inode *dir, struct dentry *direntry, 
	} else {

		rc = __cifs_do_create(dir, direntry, full_path, xid,

				      tlink, oflags, mode, oplock,

				      fid, buf, &inode);

		if (!rc)

			d_add(direntry, inode);

				      fid, buf, inode);

	}

	free_dentry_path(page);

	return rc;
@@ -504,13 +502,13 @@ static int cifs_do_create(struct inode *dir, struct dentry *direntry, 
 * Look up, create and open a CIFS file.

 *

 * The initial dentry state is in-lookup or hashed-negative.  On success, dentry

 * will become hashed-positive by calling d_drop() & d_add(), respectively.

 * will become hashed-positive by calling d_splice_alias() if in-lookup,

 * otherwise d_instantiate().

 */

int

cifs_atomic_open(struct inode *inode, struct dentry *direntry,

int cifs_atomic_open(struct inode *dir, struct dentry *direntry,

		     struct file *file, unsigned int oflags, umode_t mode)

{

	struct cifs_sb_info *cifs_sb = CIFS_SB(inode);

	struct cifs_sb_info *cifs_sb = CIFS_SB(dir);

	struct cifs_open_info_data buf = {};

	struct TCP_Server_Info *server;

	struct cifsFileInfo *file_info;
@@ -519,6 +517,8 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry, 
	struct tcon_link *tlink;

	struct cifs_tcon *tcon;

	unsigned int sbflags;

	struct dentry *alias;

	struct inode *inode;

	unsigned int xid;

	__u32 oplock;

	int rc;
@@ -545,13 +545,13 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry, 
		if (!d_in_lookup(direntry))

			return -ENOENT;



		return finish_no_open(file, cifs_lookup(inode, direntry, 0));

		return finish_no_open(file, cifs_lookup(dir, direntry, 0));

	}



	xid = get_xid();



	cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",

		 inode, direntry, direntry);

		 dir, direntry, direntry);



	tlink = cifs_sb_tlink(cifs_sb);

	if (IS_ERR(tlink)) {
@@ -572,13 +572,21 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry, 


	cifs_add_pending_open(&fid, tlink, &open);



	rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,

			    &oplock, &fid, &buf);

	rc = cifs_do_create(dir, direntry, xid, tlink, oflags, mode,

			    &oplock, &fid, &buf, &inode);

	if (rc) {

		cifs_del_pending_open(&open);

		goto out;

	}



	if (d_in_lookup(direntry)) {

		alias = d_splice_alias(inode, direntry);

		if (!IS_ERR_OR_NULL(alias))

			direntry = alias;

	} else {

		d_instantiate(direntry, inode);

	}



	if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))

		file->f_mode |= FMODE_CREATED;
@@ -622,11 +630,12 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry, 
 * Create a CIFS file.

 *

 * The initial dentry state is hashed-negative.  On success, dentry will become

 * hashed-positive by calling d_drop() & d_add(), respectively.

 * hashed-positive by calling d_instantiate().

 */

int cifs_create(struct mnt_idmap *idmap, struct inode *inode,

int cifs_create(struct mnt_idmap *idmap, struct inode *dir,

		struct dentry *direntry, umode_t mode, bool excl)

{

	struct cifs_sb_info *cifs_sb = CIFS_SB(dir);

	int rc;

	unsigned int xid = get_xid();

	/*
@@ -640,19 +649,20 @@ int cifs_create(struct mnt_idmap *idmap, struct inode *inode, 
	struct tcon_link *tlink;

	struct cifs_tcon *tcon;

	struct TCP_Server_Info *server;

	struct inode *inode;

	struct cifs_fid fid;

	__u32 oplock;

	struct cifs_open_info_data buf = {};



	cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",

		 inode, direntry, direntry);

		 dir, direntry, direntry);



	if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) {

	if (unlikely(cifs_forced_shutdown(cifs_sb))) {

		rc = smb_EIO(smb_eio_trace_forced_shutdown);

		goto out_free_xid;

	}



	tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));

	tlink = cifs_sb_tlink(cifs_sb);

	rc = PTR_ERR(tlink);

	if (IS_ERR(tlink))

		goto out_free_xid;
@@ -663,9 +673,13 @@ int cifs_create(struct mnt_idmap *idmap, struct inode *inode, 
	if (server->ops->new_lease_key)

		server->ops->new_lease_key(&fid);



	rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, &buf);

	if (!rc && server->ops->close)

	rc = cifs_do_create(dir, direntry, xid, tlink, oflags,

			    mode, &oplock, &fid, &buf, &inode);

	if (!rc) {

		d_instantiate(direntry, inode);

		if (server->ops->close)

			server->ops->close(xid, tcon, &fid);

	}



	cifs_free_open_info(&buf);

	cifs_put_tlink(tlink);
@@ -1035,7 +1049,7 @@ static int set_tmpfile_attr(const unsigned int xid, unsigned int oflags, 
 * Create a hidden temporary CIFS file with delete-on-close bit set.

 *

 * The initial dentry state is unhashed-negative.  On success, dentry will

 * become unhashed-positive by calling d_drop() & d_instantiate(), respectively.

 * become unhashed-positive by calling d_instantiate().

 */

int cifs_tmpfile(struct mnt_idmap *idmap, struct inode *dir,

		 struct file *file, umode_t mode)