smb: client: add support for O_TMPFILE (3e7d6303) · Commits · git / linux-net

fs/smb/client/cifsfs.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -124,6 +124,9 @@ MODULE_PARM_DESC(dir_cache_timeout, "Number of seconds to cache directory conten
		/* Module-wide total cached dirents (in bytes) across all tcons */
		atomic64_t cifs_dircache_bytes_used = ATOMIC64_INIT(0);

		atomic_t cifs_sillycounter;
		atomic_t cifs_tmpcounter;

		/*
		* Write-only module parameter to drop all cached directory entries across
		* all CIFS mounts. Echo a non-zero value to trigger.
		@@ -1199,6 +1202,7 @@ MODULE_ALIAS("smb3");
		const struct inode_operations cifs_dir_inode_ops = {
		.create = cifs_create,
		.atomic_open = cifs_atomic_open,
		.tmpfile = cifs_tmpfile,
		.lookup = cifs_lookup,
		.getattr = cifs_getattr,
		.unlink = cifs_unlink,

fs/smb/client/cifsfs.h

+19 −0

Original line number	Diff line number	Diff line
		@@ -13,6 +13,9 @@

		#define ROOT_I 2

		extern atomic_t cifs_sillycounter;
		extern atomic_t cifs_tmpcounter;

		/*
		* ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
		* so that it will fit. We use hash_64 to convert the value to 31 bits, and
		@@ -53,6 +56,8 @@ int cifs_create(struct mnt_idmap idmap, struct inode inode,
		struct dentry *direntry, umode_t mode, bool excl);
		int cifs_atomic_open(struct inode inode, 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);
		struct dentry cifs_lookup(struct inode parent_dir_inode,
		struct dentry *direntry, unsigned int flags);
		int cifs_unlink(struct inode dir, struct dentry dentry);
		@@ -142,6 +147,20 @@ struct smb3_fs_context;
		struct dentry cifs_smb3_do_mount(struct file_system_type fs_type, int flags,
		struct smb3_fs_context *old_ctx);

		char cifs_silly_fullpath(struct dentry dentry);

		#define CIFS_TMPNAME_PREFIX ".__smbfile_tmp"
		#define CIFS_TMPNAME_PREFIX_LEN ((int)sizeof(CIFS_TMPNAME_PREFIX) - 1)
		#define CIFS_TMPNAME_COUNTER_LEN ((int)sizeof(cifs_tmpcounter) * 2)
		#define CIFS_TMPNAME_LEN \
		(CIFS_TMPNAME_PREFIX_LEN + CIFS_TMPNAME_COUNTER_LEN)

		#define CIFS_SILLYNAME_PREFIX ".__smbfile_silly"
		#define CIFS_SILLYNAME_PREFIX_LEN ((int)sizeof(CIFS_SILLYNAME_PREFIX) - 1)
		#define CIFS_SILLYNAME_COUNTER_LEN ((int)sizeof(cifs_sillycounter) * 2)
		#define CIFS_SILLYNAME_LEN \
		(CIFS_SILLYNAME_PREFIX_LEN + CIFS_SILLYNAME_COUNTER_LEN)

		#ifdef CONFIG_CIFS_NFSD_EXPORT
		extern const struct export_operations cifs_export_ops;
		#endif /* CONFIG_CIFS_NFSD_EXPORT */

fs/smb/client/cifsglob.h

+13 −10

Original line number	Diff line number	Diff line
		@@ -1534,9 +1534,16 @@ int cifs_file_set_size(const unsigned int xid, struct dentry *dentry,
		#define CIFS_CACHE_RW_FLG (CIFS_CACHE_READ_FLG \| CIFS_CACHE_WRITE_FLG)
		#define CIFS_CACHE_RHW_FLG (CIFS_CACHE_RW_FLG \| CIFS_CACHE_HANDLE_FLG)

		/*
		* One of these for each file inode
		*/
		enum cifs_inode_flags {
		CIFS_INODE_PENDING_OPLOCK_BREAK, /* oplock break in progress */
		CIFS_INODE_PENDING_WRITERS, /* Writes in progress */
		CIFS_INODE_FLAG_UNUSED, /* Unused flag */
		CIFS_INO_DELETE_PENDING, /* delete pending on server */
		CIFS_INO_INVALID_MAPPING, /* pagecache is invalid */
		CIFS_INO_LOCK, /* lock bit for synchronization */
		CIFS_INO_TMPFILE, /* for O_TMPFILE inodes */
		CIFS_INO_CLOSE_ON_LOCK, /* Not to defer the close when lock is set */
		};

		struct cifsInodeInfo {
		struct netfs_inode netfs; /* Netfslib context and vfs inode */
		@@ -1554,13 +1561,6 @@ struct cifsInodeInfo {
		__u32 cifsAttrs; /* e.g. DOS archive bit, sparse, compressed, system */
		unsigned int oplock; /* oplock/lease level we have */
		__u16 epoch; /* used to track lease state changes */
		#define CIFS_INODE_PENDING_OPLOCK_BREAK (0) /* oplock break in progress */
		#define CIFS_INODE_PENDING_WRITERS (1) /* Writes in progress */
		#define CIFS_INODE_FLAG_UNUSED (2) /* Unused flag */
		#define CIFS_INO_DELETE_PENDING (3) /* delete pending on server */
		#define CIFS_INO_INVALID_MAPPING (4) /* pagecache is invalid */
		#define CIFS_INO_LOCK (5) /* lock bit for synchronization */
		#define CIFS_INO_CLOSE_ON_LOCK (7) /* Not to defer the close when lock is set */
		unsigned long flags;
		spinlock_t writers_lock;
		unsigned int writers; /* Number of writers on this inode */
		@@ -2259,6 +2259,7 @@ struct smb2_compound_vars {
		struct kvec qi_iov;
		struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
		struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
		struct kvec hl_iov[SMB2_SET_INFO_IOV_SIZE];
		struct kvec unlink_iov[SMB2_SET_INFO_IOV_SIZE];
		struct kvec rename_iov[SMB2_SET_INFO_IOV_SIZE];
		struct kvec close_iov;
		@@ -2383,6 +2384,8 @@ static inline int cifs_open_create_options(unsigned int oflags, int opts)
		opts \|= CREATE_WRITE_THROUGH;
		if (oflags & O_DIRECT)
		opts \|= CREATE_NO_BUFFER;
		if (oflags & O_TMPFILE)
		opts \|= CREATE_DELETE_ON_CLOSE;
		return opts;
		}

fs/smb/client/cifsproto.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -141,7 +141,8 @@ struct cifsFileInfo find_writable_file(struct cifsInodeInfo cifs_inode,
		int __cifs_get_writable_file(struct cifsInodeInfo *cifs_inode,
		unsigned int find_flags, unsigned int open_flags,
		struct cifsFileInfo **ret_file);
		int cifs_get_writable_path(struct cifs_tcon tcon, const char name, int flags,
		int cifs_get_writable_path(struct cifs_tcon tcon, const char name,
		struct inode *inode, int flags,
		struct cifsFileInfo **ret_file);
		struct cifsFileInfo __find_readable_file(struct cifsInodeInfo cifs_inode,
		unsigned int find_flags,

fs/smb/client/dir.c

+267 −46

Original line number	Diff line number	Diff line
		@@ -172,20 +172,44 @@ check_name(struct dentry direntry, struct cifs_tcon tcon)
		return 0;
		}

		static char alloc_parent_path(struct dentry dentry, size_t namelen)
		{
		struct cifs_sb_info *cifs_sb = CIFS_SB(dentry);
		void *page = alloc_dentry_path();
		const char *path;
		size_t size;
		char *npath;

		/* Inode operations in similar order to how they appear in Linux file fs.h */
		path = build_path_from_dentry(dentry->d_parent, page);
		if (IS_ERR(path)) {
		npath = ERR_CAST(path);
		goto out;
		}

		size = strlen(path) + namelen + 2;
		npath = kmalloc(size, GFP_KERNEL);
		if (!npath)
		npath = ERR_PTR(-ENOMEM);
		else
		scnprintf(npath, size, "%s%c", path, CIFS_DIR_SEP(cifs_sb));
		out:
		free_dentry_path(page);
		return npath;
		}

		static int cifs_do_create(struct inode inode, 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)
		/* Inode operations in similar order to how they appear in Linux file fs.h */
		static int __cifs_do_create(struct inode dir, struct dentry direntry,
		const char *full_path, 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 inode **inode)
		{
		int rc = -ENOENT;
		int create_options = CREATE_NOT_DIR;
		int desired_access;
		struct cifs_sb_info *cifs_sb = CIFS_SB(inode);
		struct cifs_sb_info *cifs_sb = CIFS_SB(dir);
		struct cifs_tcon *tcon = tlink_tcon(tlink);
		const char *full_path;
		void *page = alloc_dentry_path();
		struct inode *newinode = NULL;
		unsigned int sbflags = cifs_sb_flags(cifs_sb);
		int disposition;
		@@ -199,21 +223,15 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		if (tcon->ses->server->oplocks)
		*oplock = REQ_OPLOCK;

		full_path = build_path_from_dentry(direntry, page);
		if (IS_ERR(full_path)) {
		rc = PTR_ERR(full_path);
		goto out;
		}

		/* If we're caching, we need to be able to fill in around partial writes. */
		if (cifs_fscache_enabled(inode) && (oflags & O_ACCMODE) == O_WRONLY)
		if (cifs_fscache_enabled(dir) && (oflags & O_ACCMODE) == O_WRONLY)
		rdwr_for_fscache = 1;

		#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
		if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
		(CIFS_UNIX_POSIX_PATH_OPS_CAP &
		le64_to_cpu(tcon->fsUnixInfo.Capability))) {
		rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
		rc = cifs_posix_open(full_path, &newinode, dir->i_sb, mode,
		oflags, oplock, &fid->netfid, xid);
		switch (rc) {
		case 0:
		@@ -225,8 +243,7 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		if (S_ISDIR(newinode->i_mode)) {
		CIFSSMBClose(xid, tcon, fid->netfid);
		iput(newinode);
		rc = -EISDIR;
		goto out;
		return -EISDIR;
		}

		if (!S_ISREG(newinode->i_mode)) {
		@@ -269,7 +286,7 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		break;

		default:
		goto out;
		return rc;
		}
		/*
		* fallthrough to retry, using older open call, this is case
		@@ -287,26 +304,30 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		desired_access \|= GENERIC_WRITE;
		if (rdwr_for_fscache == 1)
		desired_access \|= GENERIC_READ;
		if (oflags & O_TMPFILE)
		desired_access \|= DELETE;

		disposition = FILE_OVERWRITE_IF;
		if ((oflags & (O_CREAT \| O_EXCL)) == (O_CREAT \| O_EXCL))
		if (oflags & O_CREAT) {
		if (oflags & O_EXCL)
		disposition = FILE_CREATE;
		else if ((oflags & (O_CREAT \| O_TRUNC)) == (O_CREAT \| O_TRUNC))
		else if (oflags & O_TRUNC)
		disposition = FILE_OVERWRITE_IF;
		else if ((oflags & O_CREAT) == O_CREAT)
		disposition = FILE_OPEN_IF;
		else
		disposition = FILE_OPEN_IF;
		} else if (oflags & O_TMPFILE) {
		disposition = FILE_CREATE;
		} else {
		cifs_dbg(FYI, "Create flag not set in create function\n");
		}

		/*
		* BB add processing to set equivalent of mode - e.g. via CreateX with
		* ACLs
		*/

		if (!server->ops->open) {
		rc = -ENOSYS;
		goto out;
		}
		if (!server->ops->open)
		return -EOPNOTSUPP;

		create_options \|= cifs_open_create_options(oflags, create_options);
		/*
		@@ -358,10 +379,10 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		rdwr_for_fscache = 2;
		goto retry_open;
		}
		goto out;
		return rc;
		}
		if (rdwr_for_fscache == 2)
		cifs_invalidate_cache(inode, FSCACHE_INVAL_DIO_WRITE);
		cifs_invalidate_cache(dir, FSCACHE_INVAL_DIO_WRITE);

		#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
		/*
		@@ -379,8 +400,8 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned

		if (sbflags & CIFS_MOUNT_SET_UID) {
		args.uid = current_fsuid();
		if (inode->i_mode & S_ISGID)
		args.gid = inode->i_gid;
		if (dir->i_mode & S_ISGID)
		args.gid = dir->i_gid;
		else
		args.gid = current_fsgid();
		} else {
		@@ -402,14 +423,14 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		cifs_create_get_file_info:
		/* server might mask mode so we have to query for it */
		if (tcon->unix_ext)
		rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
		rc = cifs_get_inode_info_unix(&newinode, full_path, dir->i_sb,
		xid);
		else {
		#else
		{
		#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
		/* TODO: Add support for calling POSIX query info here, but passing in fid */
		rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb, xid, fid);
		rc = cifs_get_inode_info(&newinode, full_path, buf, dir->i_sb, xid, fid);
		if (newinode) {
		if (server->ops->set_lease_key)
		server->ops->set_lease_key(newinode, fid);
		@@ -418,8 +439,8 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		newinode->i_mode = mode;
		if (sbflags & CIFS_MOUNT_SET_UID) {
		newinode->i_uid = current_fsuid();
		if (inode->i_mode & S_ISGID)
		newinode->i_gid = inode->i_gid;
		if (dir->i_mode & S_ISGID)
		newinode->i_gid = dir->i_gid;
		else
		newinode->i_gid = current_fsgid();
		}
		@@ -436,17 +457,13 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		goto out_err;
		}

		if (newinode)
		if (S_ISDIR(newinode->i_mode)) {
		if (newinode && S_ISDIR(newinode->i_mode)) {
		rc = -EISDIR;
		goto out_err;
		}

		d_drop(direntry);
		d_add(direntry, newinode);

		out:
		free_dentry_path(page);
		*inode = newinode;
		return rc;

		out_err:
		@@ -454,9 +471,41 @@ static int cifs_do_create(struct inode inode, struct dentry direntry, unsigned
		server->ops->close(xid, tcon, fid);
		if (newinode)
		iput(newinode);
		goto out;
		return rc;
		}

		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)
		{
		void *page = alloc_dentry_path();
		const char *full_path;
		struct inode *inode;
		int rc;

		full_path = build_path_from_dentry(direntry, page);
		if (IS_ERR(full_path)) {
		rc = PTR_ERR(full_path);
		} else {
		rc = __cifs_do_create(dir, direntry, full_path, xid,
		tlink, oflags, mode, oplock,
		fid, buf, &inode);
		if (!rc)
		d_add(direntry, inode);
		}
		free_dentry_path(page);
		return rc;
		}


		/*
		* 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.
		*/
		int
		cifs_atomic_open(struct inode inode, struct dentry direntry,
		struct file *file, unsigned int oflags, umode_t mode)
		@@ -569,6 +618,12 @@ cifs_atomic_open(struct inode inode, struct dentry direntry,
		return rc;
		}

		/*
		* 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.
		*/
		int cifs_create(struct mnt_idmap idmap, struct inode inode,
		struct dentry *direntry, umode_t mode, bool excl)
		{
		@@ -959,6 +1014,172 @@ static int cifs_ci_compare(const struct dentry *dentry,
		return 0;
		}

		static int set_hidden_attr(const unsigned int xid,
		struct TCP_Server_Info *server,
		struct file *file)
		{
		struct dentry *dentry = file->f_path.dentry;
		struct cifsInodeInfo *cinode = CIFS_I(d_inode(dentry));
		FILE_BASIC_INFO fi = {
		.Attributes = cpu_to_le32(cinode->cifsAttrs \|
		ATTR_HIDDEN),
		};
		void *page = alloc_dentry_path();
		const char *full_path;
		int rc;

		full_path = build_path_from_dentry(dentry, page);
		if (IS_ERR(full_path))
		rc = PTR_ERR(full_path);
		else
		rc = server->ops->set_file_info(d_inode(dentry),
		full_path, &fi, xid);
		free_dentry_path(page);
		return rc;
		}

		/*
		* 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.
		*/
		int cifs_tmpfile(struct mnt_idmap idmap, struct inode dir,
		struct file *file, umode_t mode)
		{
		struct dentry *dentry = file->f_path.dentry;
		struct cifs_sb_info *cifs_sb = CIFS_SB(dir);
		size_t size = CIFS_TMPNAME_LEN + 1;
		int retries = 0, max_retries = 16;
		struct TCP_Server_Info *server;
		struct cifs_pending_open open;
		struct cifsFileInfo *cfile;
		struct cifs_fid fid = {};
		struct tcon_link *tlink;
		struct cifs_tcon *tcon;
		unsigned int sbflags;
		struct inode *inode;
		char path, name;
		unsigned int xid;
		__u32 oplock;
		int rc;

		if (unlikely(cifs_forced_shutdown(cifs_sb)))
		return smb_EIO(smb_eio_trace_forced_shutdown);

		tlink = cifs_sb_tlink(cifs_sb);
		if (IS_ERR(tlink))
		return PTR_ERR(tlink);
		tcon = tlink_tcon(tlink);
		server = tcon->ses->server;

		xid = get_xid();

		if (server->vals->protocol_id < SMB20_PROT_ID) {
		cifs_dbg(VFS \| ONCE, "O_TMPFILE is supported only in SMB2+\n");
		rc = -EOPNOTSUPP;
		goto out;
		}

		if (server->ops->new_lease_key)
		server->ops->new_lease_key(&fid);
		cifs_add_pending_open(&fid, tlink, &open);

		path = alloc_parent_path(dentry, size - 1);
		if (IS_ERR(path)) {
		cifs_del_pending_open(&open);
		rc = PTR_ERR(path);
		goto out;
		}

		name = path + strlen(path);
		do {
		scnprintf(name, size,
		CIFS_TMPNAME_PREFIX "%0*x",
		CIFS_TMPNAME_COUNTER_LEN,
		atomic_inc_return(&cifs_tmpcounter));
		rc = __cifs_do_create(dir, dentry, path, xid, tlink,
		file->f_flags, mode, &oplock,
		&fid, NULL, &inode);
		if (!rc) {
		set_nlink(inode, 0);
		mark_inode_dirty(inode);
		d_mark_tmpfile_name(file, &QSTR_LEN(name, size - 1));
		d_instantiate(dentry, inode);
		break;
		}
		} while (unlikely(rc == -EEXIST) && ++retries < max_retries);

		kfree(path);
		if (rc) {
		cifs_del_pending_open(&open);
		goto out;
		}

		rc = finish_open(file, dentry, generic_file_open);
		if (rc)
		goto err_open;

		sbflags = cifs_sb_flags(cifs_sb);
		if ((file->f_flags & O_DIRECT) && (sbflags & CIFS_MOUNT_STRICT_IO)) {
		if (sbflags & CIFS_MOUNT_NO_BRL)
		file->f_op = &cifs_file_direct_nobrl_ops;
		else
		file->f_op = &cifs_file_direct_ops;
		}

		cfile = cifs_new_fileinfo(&fid, file, tlink, oplock, NULL);
		if (!cfile) {
		rc = -ENOMEM;
		goto err_open;
		}

		rc = set_hidden_attr(xid, server, file);
		if (rc)
		goto out;

		fscache_use_cookie(cifs_inode_cookie(file_inode(file)),
		file->f_mode & FMODE_WRITE);
		out:
		cifs_put_tlink(tlink);
		free_xid(xid);
		return rc;
		err_open:
		cifs_del_pending_open(&open);
		if (server->ops->close)
		server->ops->close(xid, tcon, &fid);
		goto out;
		}

		char cifs_silly_fullpath(struct dentry dentry)
		{
		unsigned char name[CIFS_SILLYNAME_LEN + 1];
		int retries = 0, max_retries = 16;
		size_t namesize = sizeof(name);
		struct dentry *sdentry = NULL;
		char *path;

		do {
		dput(sdentry);
		scnprintf(name, namesize,
		CIFS_SILLYNAME_PREFIX "%0*x",
		CIFS_SILLYNAME_COUNTER_LEN,
		atomic_inc_return(&cifs_sillycounter));
		sdentry = lookup_noperm(&QSTR(name), dentry->d_parent);
		if (IS_ERR(sdentry))
		return ERR_CAST(sdentry);
		if (d_is_negative(sdentry)) {
		dput(sdentry);
		path = alloc_parent_path(dentry, CIFS_SILLYNAME_LEN);
		if (!IS_ERR(path))
		strcat(path, name);
		return path;
		}
		} while (++retries < max_retries);
		dput(sdentry);
		return ERR_PTR(-EBUSY);
		}

		const struct dentry_operations cifs_ci_dentry_ops = {
		.d_revalidate = cifs_d_revalidate,
		.d_hash = cifs_ci_hash,