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1// SPDX-License-Identifier: LGPL-2.12/*3 *4 *   vfs operations that deal with dentries5 *6 *   Copyright (C) International Business Machines  Corp., 2002,20097 *   Author(s): Steve French (sfrench@us.ibm.com)8 *9 */10#include <linux/fs.h>11#include <linux/stat.h>12#include <linux/slab.h>13#include <linux/namei.h>14#include <linux/mount.h>15#include <linux/file.h>16#include "cifsfs.h"17#include "cifspdu.h"18#include "cifsglob.h"19#include "cifsproto.h"20#include "cifs_debug.h"21#include "cifs_fs_sb.h"22#include "cifs_unicode.h"23#include "fs_context.h"24#include "cifs_ioctl.h"25#include "fscache.h"26 27static void28renew_parental_timestamps(struct dentry *direntry)29{30	/* BB check if there is a way to get the kernel to do this or if we31	   really need this */32	do {33		cifs_set_time(direntry, jiffies);34		direntry = direntry->d_parent;35	} while (!IS_ROOT(direntry));36}37 38char *39cifs_build_path_to_root(struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,40			struct cifs_tcon *tcon, int add_treename)41{42	int pplen = ctx->prepath ? strlen(ctx->prepath) + 1 : 0;43	int dfsplen;44	char *full_path = NULL;45 46	/* if no prefix path, simply set path to the root of share to "" */47	if (pplen == 0) {48		full_path = kzalloc(1, GFP_KERNEL);49		return full_path;50	}51 52	if (add_treename)53		dfsplen = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1);54	else55		dfsplen = 0;56 57	full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);58	if (full_path == NULL)59		return full_path;60 61	if (dfsplen)62		memcpy(full_path, tcon->tree_name, dfsplen);63	full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb);64	memcpy(full_path + dfsplen + 1, ctx->prepath, pplen);65	convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));66	return full_path;67}68 69/* Note: caller must free return buffer */70const char *71build_path_from_dentry(struct dentry *direntry, void *page)72{73	struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);74	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);75	bool prefix = tcon->Flags & SMB_SHARE_IS_IN_DFS;76 77	return build_path_from_dentry_optional_prefix(direntry, page,78						      prefix);79}80 81char *__build_path_from_dentry_optional_prefix(struct dentry *direntry, void *page,82					       const char *tree, int tree_len,83					       bool prefix)84{85	int dfsplen;86	int pplen = 0;87	struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);88	char dirsep = CIFS_DIR_SEP(cifs_sb);89	char *s;90 91	if (unlikely(!page))92		return ERR_PTR(-ENOMEM);93 94	if (prefix)95		dfsplen = strnlen(tree, tree_len + 1);96	else97		dfsplen = 0;98 99	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)100		pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;101 102	s = dentry_path_raw(direntry, page, PATH_MAX);103	if (IS_ERR(s))104		return s;105	if (!s[1])	// for root we want "", not "/"106		s++;107	if (s < (char *)page + pplen + dfsplen)108		return ERR_PTR(-ENAMETOOLONG);109	if (pplen) {110		cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);111		s -= pplen;112		memcpy(s + 1, cifs_sb->prepath, pplen - 1);113		*s = '/';114	}115	if (dirsep != '/') {116		/* BB test paths to Windows with '/' in the midst of prepath */117		char *p;118 119		for (p = s; *p; p++)120			if (*p == '/')121				*p = dirsep;122	}123	if (dfsplen) {124		s -= dfsplen;125		memcpy(s, tree, dfsplen);126		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {127			int i;128			for (i = 0; i < dfsplen; i++) {129				if (s[i] == '\\')130					s[i] = '/';131			}132		}133	}134	return s;135}136 137char *build_path_from_dentry_optional_prefix(struct dentry *direntry, void *page,138					     bool prefix)139{140	struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);141	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);142 143	return __build_path_from_dentry_optional_prefix(direntry, page, tcon->tree_name,144							MAX_TREE_SIZE, prefix);145}146 147/*148 * Don't allow path components longer than the server max.149 * Don't allow the separator character in a path component.150 * The VFS will not allow "/", but "\" is allowed by posix.151 */152static int153check_name(struct dentry *direntry, struct cifs_tcon *tcon)154{155	struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);156	int i;157 158	if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&159		     direntry->d_name.len >160		     le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))161		return -ENAMETOOLONG;162 163	if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {164		for (i = 0; i < direntry->d_name.len; i++) {165			if (direntry->d_name.name[i] == '\\') {166				cifs_dbg(FYI, "Invalid file name\n");167				return -EINVAL;168			}169		}170	}171	return 0;172}173 174 175/* Inode operations in similar order to how they appear in Linux file fs.h */176 177static int cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,178			  struct tcon_link *tlink, unsigned int oflags, umode_t mode, __u32 *oplock,179			  struct cifs_fid *fid, struct cifs_open_info_data *buf)180{181	int rc = -ENOENT;182	int create_options = CREATE_NOT_DIR;183	int desired_access;184	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);185	struct cifs_tcon *tcon = tlink_tcon(tlink);186	const char *full_path;187	void *page = alloc_dentry_path();188	struct inode *newinode = NULL;189	int disposition;190	struct TCP_Server_Info *server = tcon->ses->server;191	struct cifs_open_parms oparms;192	int rdwr_for_fscache = 0;193 194	*oplock = 0;195	if (tcon->ses->server->oplocks)196		*oplock = REQ_OPLOCK;197 198	full_path = build_path_from_dentry(direntry, page);199	if (IS_ERR(full_path)) {200		free_dentry_path(page);201		return PTR_ERR(full_path);202	}203 204	/* If we're caching, we need to be able to fill in around partial writes. */205	if (cifs_fscache_enabled(inode) && (oflags & O_ACCMODE) == O_WRONLY)206		rdwr_for_fscache = 1;207 208#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY209	if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&210	    (CIFS_UNIX_POSIX_PATH_OPS_CAP &211			le64_to_cpu(tcon->fsUnixInfo.Capability))) {212		rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,213				     oflags, oplock, &fid->netfid, xid);214		switch (rc) {215		case 0:216			if (newinode == NULL) {217				/* query inode info */218				goto cifs_create_get_file_info;219			}220 221			if (S_ISDIR(newinode->i_mode)) {222				CIFSSMBClose(xid, tcon, fid->netfid);223				iput(newinode);224				rc = -EISDIR;225				goto out;226			}227 228			if (!S_ISREG(newinode->i_mode)) {229				/*230				 * The server may allow us to open things like231				 * FIFOs, but the client isn't set up to deal232				 * with that. If it's not a regular file, just233				 * close it and proceed as if it were a normal234				 * lookup.235				 */236				CIFSSMBClose(xid, tcon, fid->netfid);237				goto cifs_create_get_file_info;238			}239			/* success, no need to query */240			goto cifs_create_set_dentry;241 242		case -ENOENT:243			goto cifs_create_get_file_info;244 245		case -EIO:246		case -EINVAL:247			/*248			 * EIO could indicate that (posix open) operation is not249			 * supported, despite what server claimed in capability250			 * negotiation.251			 *252			 * POSIX open in samba versions 3.3.1 and earlier could253			 * incorrectly fail with invalid parameter.254			 */255			tcon->broken_posix_open = true;256			break;257 258		case -EREMOTE:259		case -EOPNOTSUPP:260			/*261			 * EREMOTE indicates DFS junction, which is not handled262			 * in posix open.  If either that or op not supported263			 * returned, follow the normal lookup.264			 */265			break;266 267		default:268			goto out;269		}270		/*271		 * fallthrough to retry, using older open call, this is case272		 * where server does not support this SMB level, and falsely273		 * claims capability (also get here for DFS case which should be274		 * rare for path not covered on files)275		 */276	}277#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */278 279	desired_access = 0;280	if (OPEN_FMODE(oflags) & FMODE_READ)281		desired_access |= GENERIC_READ; /* is this too little? */282	if (OPEN_FMODE(oflags) & FMODE_WRITE)283		desired_access |= GENERIC_WRITE;284	if (rdwr_for_fscache == 1)285		desired_access |= GENERIC_READ;286 287	disposition = FILE_OVERWRITE_IF;288	if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))289		disposition = FILE_CREATE;290	else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))291		disposition = FILE_OVERWRITE_IF;292	else if ((oflags & O_CREAT) == O_CREAT)293		disposition = FILE_OPEN_IF;294	else295		cifs_dbg(FYI, "Create flag not set in create function\n");296 297	/*298	 * BB add processing to set equivalent of mode - e.g. via CreateX with299	 * ACLs300	 */301 302	if (!server->ops->open) {303		rc = -ENOSYS;304		goto out;305	}306 307	/*308	 * if we're not using unix extensions, see if we need to set309	 * ATTR_READONLY on the create call310	 */311	if (!tcon->unix_ext && (mode & S_IWUGO) == 0)312		create_options |= CREATE_OPTION_READONLY;313 314retry_open:315	oparms = (struct cifs_open_parms) {316		.tcon = tcon,317		.cifs_sb = cifs_sb,318		.desired_access = desired_access,319		.create_options = cifs_create_options(cifs_sb, create_options),320		.disposition = disposition,321		.path = full_path,322		.fid = fid,323		.mode = mode,324	};325	rc = server->ops->open(xid, &oparms, oplock, buf);326	if (rc) {327		cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);328		if (rc == -EACCES && rdwr_for_fscache == 1) {329			desired_access &= ~GENERIC_READ;330			rdwr_for_fscache = 2;331			goto retry_open;332		}333		goto out;334	}335	if (rdwr_for_fscache == 2)336		cifs_invalidate_cache(inode, FSCACHE_INVAL_DIO_WRITE);337 338#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY339	/*340	 * If Open reported that we actually created a file then we now have to341	 * set the mode if possible.342	 */343	if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {344		struct cifs_unix_set_info_args args = {345				.mode	= mode,346				.ctime	= NO_CHANGE_64,347				.atime	= NO_CHANGE_64,348				.mtime	= NO_CHANGE_64,349				.device	= 0,350		};351 352		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {353			args.uid = current_fsuid();354			if (inode->i_mode & S_ISGID)355				args.gid = inode->i_gid;356			else357				args.gid = current_fsgid();358		} else {359			args.uid = INVALID_UID; /* no change */360			args.gid = INVALID_GID; /* no change */361		}362		CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,363				       current->tgid);364	} else {365		/*366		 * BB implement mode setting via Windows security367		 * descriptors e.g.368		 */369		/* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/370 371		/* Could set r/o dos attribute if mode & 0222 == 0 */372	}373 374cifs_create_get_file_info:375	/* server might mask mode so we have to query for it */376	if (tcon->unix_ext)377		rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,378					      xid);379	else {380#else381	{382#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */383		/* TODO: Add support for calling POSIX query info here, but passing in fid */384		rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb, xid, fid);385		if (newinode) {386			if (server->ops->set_lease_key)387				server->ops->set_lease_key(newinode, fid);388			if ((*oplock & CIFS_CREATE_ACTION) && S_ISREG(newinode->i_mode)) {389				if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)390					newinode->i_mode = mode;391				if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {392					newinode->i_uid = current_fsuid();393					if (inode->i_mode & S_ISGID)394						newinode->i_gid = inode->i_gid;395					else396						newinode->i_gid = current_fsgid();397				}398			}399		}400	}401 402#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY403cifs_create_set_dentry:404#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */405	if (rc != 0) {406		cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",407			 rc);408		goto out_err;409	}410 411	if (newinode)412		if (S_ISDIR(newinode->i_mode)) {413			rc = -EISDIR;414			goto out_err;415		}416 417	d_drop(direntry);418	d_add(direntry, newinode);419 420out:421	free_dentry_path(page);422	return rc;423 424out_err:425	if (server->ops->close)426		server->ops->close(xid, tcon, fid);427	if (newinode)428		iput(newinode);429	goto out;430}431 432int433cifs_atomic_open(struct inode *inode, struct dentry *direntry,434		 struct file *file, unsigned oflags, umode_t mode)435{436	int rc;437	unsigned int xid;438	struct tcon_link *tlink;439	struct cifs_tcon *tcon;440	struct TCP_Server_Info *server;441	struct cifs_fid fid = {};442	struct cifs_pending_open open;443	__u32 oplock;444	struct cifsFileInfo *file_info;445	struct cifs_open_info_data buf = {};446 447	if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb))))448		return -EIO;449 450	/*451	 * Posix open is only called (at lookup time) for file create now. For452	 * opens (rather than creates), because we do not know if it is a file453	 * or directory yet, and current Samba no longer allows us to do posix454	 * open on dirs, we could end up wasting an open call on what turns out455	 * to be a dir. For file opens, we wait to call posix open till456	 * cifs_open.  It could be added to atomic_open in the future but the457	 * performance tradeoff of the extra network request when EISDIR or458	 * EACCES is returned would have to be weighed against the 50% reduction459	 * in network traffic in the other paths.460	 */461	if (!(oflags & O_CREAT)) {462		struct dentry *res;463 464		/*465		 * Check for hashed negative dentry. We have already revalidated466		 * the dentry and it is fine. No need to perform another lookup.467		 */468		if (!d_in_lookup(direntry))469			return -ENOENT;470 471		res = cifs_lookup(inode, direntry, 0);472		if (IS_ERR(res))473			return PTR_ERR(res);474 475		return finish_no_open(file, res);476	}477 478	xid = get_xid();479 480	cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",481		 inode, direntry, direntry);482 483	tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));484	if (IS_ERR(tlink)) {485		rc = PTR_ERR(tlink);486		goto out_free_xid;487	}488 489	tcon = tlink_tcon(tlink);490 491	rc = check_name(direntry, tcon);492	if (rc)493		goto out;494 495	server = tcon->ses->server;496 497	if (server->ops->new_lease_key)498		server->ops->new_lease_key(&fid);499 500	cifs_add_pending_open(&fid, tlink, &open);501 502	rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,503			    &oplock, &fid, &buf);504	if (rc) {505		cifs_del_pending_open(&open);506		goto out;507	}508 509	if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))510		file->f_mode |= FMODE_CREATED;511 512	rc = finish_open(file, direntry, generic_file_open);513	if (rc) {514		if (server->ops->close)515			server->ops->close(xid, tcon, &fid);516		cifs_del_pending_open(&open);517		goto out;518	}519 520	if (file->f_flags & O_DIRECT &&521	    CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {522		if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)523			file->f_op = &cifs_file_direct_nobrl_ops;524		else525			file->f_op = &cifs_file_direct_ops;526		}527 528	file_info = cifs_new_fileinfo(&fid, file, tlink, oplock, buf.symlink_target);529	if (file_info == NULL) {530		if (server->ops->close)531			server->ops->close(xid, tcon, &fid);532		cifs_del_pending_open(&open);533		rc = -ENOMEM;534		goto out;535	}536 537	fscache_use_cookie(cifs_inode_cookie(file_inode(file)),538			   file->f_mode & FMODE_WRITE);539 540out:541	cifs_put_tlink(tlink);542out_free_xid:543	free_xid(xid);544	cifs_free_open_info(&buf);545	return rc;546}547 548int cifs_create(struct mnt_idmap *idmap, struct inode *inode,549		struct dentry *direntry, umode_t mode, bool excl)550{551	int rc;552	unsigned int xid = get_xid();553	/*554	 * BB below access is probably too much for mknod to request555	 *    but we have to do query and setpathinfo so requesting556	 *    less could fail (unless we want to request getatr and setatr557	 *    permissions (only).  At least for POSIX we do not have to558	 *    request so much.559	 */560	unsigned oflags = O_EXCL | O_CREAT | O_RDWR;561	struct tcon_link *tlink;562	struct cifs_tcon *tcon;563	struct TCP_Server_Info *server;564	struct cifs_fid fid;565	__u32 oplock;566	struct cifs_open_info_data buf = {};567 568	cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",569		 inode, direntry, direntry);570 571	if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) {572		rc = -EIO;573		goto out_free_xid;574	}575 576	tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));577	rc = PTR_ERR(tlink);578	if (IS_ERR(tlink))579		goto out_free_xid;580 581	tcon = tlink_tcon(tlink);582	server = tcon->ses->server;583 584	if (server->ops->new_lease_key)585		server->ops->new_lease_key(&fid);586 587	rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, &buf);588	if (!rc && server->ops->close)589		server->ops->close(xid, tcon, &fid);590 591	cifs_free_open_info(&buf);592	cifs_put_tlink(tlink);593out_free_xid:594	free_xid(xid);595	return rc;596}597 598int cifs_mknod(struct mnt_idmap *idmap, struct inode *inode,599	       struct dentry *direntry, umode_t mode, dev_t device_number)600{601	int rc = -EPERM;602	unsigned int xid;603	struct cifs_sb_info *cifs_sb;604	struct tcon_link *tlink;605	struct cifs_tcon *tcon;606	const char *full_path;607	void *page;608 609	if (!old_valid_dev(device_number))610		return -EINVAL;611 612	cifs_sb = CIFS_SB(inode->i_sb);613	if (unlikely(cifs_forced_shutdown(cifs_sb)))614		return -EIO;615 616	tlink = cifs_sb_tlink(cifs_sb);617	if (IS_ERR(tlink))618		return PTR_ERR(tlink);619 620	page = alloc_dentry_path();621	tcon = tlink_tcon(tlink);622	xid = get_xid();623 624	full_path = build_path_from_dentry(direntry, page);625	if (IS_ERR(full_path)) {626		rc = PTR_ERR(full_path);627		goto mknod_out;628	}629 630	trace_smb3_mknod_enter(xid, tcon->ses->Suid, tcon->tid, full_path);631 632	rc = tcon->ses->server->ops->make_node(xid, inode, direntry, tcon,633					       full_path, mode,634					       device_number);635 636mknod_out:637	if (rc)638		trace_smb3_mknod_err(xid,  tcon->ses->Suid, tcon->tid, rc);639	else640		trace_smb3_mknod_done(xid, tcon->ses->Suid, tcon->tid);641 642	free_dentry_path(page);643	free_xid(xid);644	cifs_put_tlink(tlink);645	return rc;646}647 648struct dentry *649cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,650	    unsigned int flags)651{652	unsigned int xid;653	int rc = 0; /* to get around spurious gcc warning, set to zero here */654	struct cifs_sb_info *cifs_sb;655	struct tcon_link *tlink;656	struct cifs_tcon *pTcon;657	struct inode *newInode = NULL;658	const char *full_path;659	void *page;660	int retry_count = 0;661 662	xid = get_xid();663 664	cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",665		 parent_dir_inode, direntry, direntry);666 667	/* check whether path exists */668 669	cifs_sb = CIFS_SB(parent_dir_inode->i_sb);670	tlink = cifs_sb_tlink(cifs_sb);671	if (IS_ERR(tlink)) {672		free_xid(xid);673		return ERR_CAST(tlink);674	}675	pTcon = tlink_tcon(tlink);676 677	rc = check_name(direntry, pTcon);678	if (unlikely(rc)) {679		cifs_put_tlink(tlink);680		free_xid(xid);681		return ERR_PTR(rc);682	}683 684	/* can not grab the rename sem here since it would685	deadlock in the cases (beginning of sys_rename itself)686	in which we already have the sb rename sem */687	page = alloc_dentry_path();688	full_path = build_path_from_dentry(direntry, page);689	if (IS_ERR(full_path)) {690		cifs_put_tlink(tlink);691		free_xid(xid);692		free_dentry_path(page);693		return ERR_CAST(full_path);694	}695 696	if (d_really_is_positive(direntry)) {697		cifs_dbg(FYI, "non-NULL inode in lookup\n");698	} else {699		cifs_dbg(FYI, "NULL inode in lookup\n");700	}701	cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",702		 full_path, d_inode(direntry));703 704again:705	if (pTcon->posix_extensions) {706		rc = smb311_posix_get_inode_info(&newInode, full_path, NULL,707						 parent_dir_inode->i_sb, xid);708	} else if (pTcon->unix_ext) {709		rc = cifs_get_inode_info_unix(&newInode, full_path,710					      parent_dir_inode->i_sb, xid);711	} else {712		rc = cifs_get_inode_info(&newInode, full_path, NULL,713				parent_dir_inode->i_sb, xid, NULL);714	}715 716	if (rc == 0) {717		/* since paths are not looked up by component - the parent718		   directories are presumed to be good here */719		renew_parental_timestamps(direntry);720	} else if (rc == -EAGAIN && retry_count++ < 10) {721		goto again;722	} else if (rc == -ENOENT) {723		cifs_set_time(direntry, jiffies);724		newInode = NULL;725	} else {726		if (rc != -EACCES) {727			cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);728			/* We special case check for Access Denied - since that729			is a common return code */730		}731		newInode = ERR_PTR(rc);732	}733	free_dentry_path(page);734	cifs_put_tlink(tlink);735	free_xid(xid);736	return d_splice_alias(newInode, direntry);737}738 739static int740cifs_d_revalidate(struct dentry *direntry, unsigned int flags)741{742	struct inode *inode;743	int rc;744 745	if (flags & LOOKUP_RCU)746		return -ECHILD;747 748	if (d_really_is_positive(direntry)) {749		inode = d_inode(direntry);750		if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))751			CIFS_I(inode)->time = 0; /* force reval */752 753		rc = cifs_revalidate_dentry(direntry);754		if (rc) {755			cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);756			switch (rc) {757			case -ENOENT:758			case -ESTALE:759				/*760				 * Those errors mean the dentry is invalid761				 * (file was deleted or recreated)762				 */763				return 0;764			default:765				/*766				 * Otherwise some unexpected error happened767				 * report it as-is to VFS layer768				 */769				return rc;770			}771		}772		else {773			/*774			 * If the inode wasn't known to be a dfs entry when775			 * the dentry was instantiated, such as when created776			 * via ->readdir(), it needs to be set now since the777			 * attributes will have been updated by778			 * cifs_revalidate_dentry().779			 */780			if (IS_AUTOMOUNT(inode) &&781			   !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {782				spin_lock(&direntry->d_lock);783				direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;784				spin_unlock(&direntry->d_lock);785			}786 787			return 1;788		}789	}790 791	/*792	 * This may be nfsd (or something), anyway, we can't see the793	 * intent of this. So, since this can be for creation, drop it.794	 */795	if (!flags)796		return 0;797 798	/*799	 * Drop the negative dentry, in order to make sure to use the800	 * case sensitive name which is specified by user if this is801	 * for creation.802	 */803	if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))804		return 0;805 806	if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)807		return 0;808 809	return 1;810}811 812/* static int cifs_d_delete(struct dentry *direntry)813{814	int rc = 0;815 816	cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);817 818	return rc;819}     */820 821const struct dentry_operations cifs_dentry_ops = {822	.d_revalidate = cifs_d_revalidate,823	.d_automount = cifs_d_automount,824/* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */825};826 827static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)828{829	struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;830	unsigned long hash;831	wchar_t c;832	int i, charlen;833 834	hash = init_name_hash(dentry);835	for (i = 0; i < q->len; i += charlen) {836		charlen = codepage->char2uni(&q->name[i], q->len - i, &c);837		/* error out if we can't convert the character */838		if (unlikely(charlen < 0))839			return charlen;840		hash = partial_name_hash(cifs_toupper(c), hash);841	}842	q->hash = end_name_hash(hash);843 844	return 0;845}846 847static int cifs_ci_compare(const struct dentry *dentry,848		unsigned int len, const char *str, const struct qstr *name)849{850	struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;851	wchar_t c1, c2;852	int i, l1, l2;853 854	/*855	 * We make the assumption here that uppercase characters in the local856	 * codepage are always the same length as their lowercase counterparts.857	 *858	 * If that's ever not the case, then this will fail to match it.859	 */860	if (name->len != len)861		return 1;862 863	for (i = 0; i < len; i += l1) {864		/* Convert characters in both strings to UTF-16. */865		l1 = codepage->char2uni(&str[i], len - i, &c1);866		l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);867 868		/*869		 * If we can't convert either character, just declare it to870		 * be 1 byte long and compare the original byte.871		 */872		if (unlikely(l1 < 0 && l2 < 0)) {873			if (str[i] != name->name[i])874				return 1;875			l1 = 1;876			continue;877		}878 879		/*880		 * Here, we again ass|u|me that upper/lowercase versions of881		 * a character are the same length in the local NLS.882		 */883		if (l1 != l2)884			return 1;885 886		/* Now compare uppercase versions of these characters */887		if (cifs_toupper(c1) != cifs_toupper(c2))888			return 1;889	}890 891	return 0;892}893 894const struct dentry_operations cifs_ci_dentry_ops = {895	.d_revalidate = cifs_d_revalidate,896	.d_hash = cifs_ci_hash,897	.d_compare = cifs_ci_compare,898	.d_automount = cifs_d_automount,899};900