[linux-block.git] / fs / cifs / cached_dir.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  Functions to handle the cached directory entries
 *
 *  Copyright (c) 2022, Ronnie Sahlberg <lsahlber@redhat.com>
 */

#include <linux/namei.h>
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "smb2proto.h"
#include "cached_dir.h"

static struct cached_fid *init_cached_dir(const char *path);
static void free_cached_dir(struct cached_fid *cfid);

static struct cached_fid *find_or_create_cached_dir(struct cached_fids *cfids,
						    const char *path,
						    bool lookup_only)
{
	struct cached_fid *cfid;

	spin_lock(&cfids->cfid_list_lock);
	list_for_each_entry(cfid, &cfids->entries, entry) {
		if (!strcmp(cfid->path, path)) {
			/*
			 * If it doesn't have a lease it is either not yet
			 * fully cached or it may be in the process of
			 * being deleted due to a lease break.
			 */
			if (!cfid->has_lease) {
				spin_unlock(&cfids->cfid_list_lock);
				return NULL;
			}
			kref_get(&cfid->refcount);
			spin_unlock(&cfids->cfid_list_lock);
			return cfid;
		}
	}
	if (lookup_only) {
		spin_unlock(&cfids->cfid_list_lock);
		return NULL;
	}
	if (cfids->num_entries >= MAX_CACHED_FIDS) {
		spin_unlock(&cfids->cfid_list_lock);
		return NULL;
	}
	cfid = init_cached_dir(path);
	if (cfid == NULL) {
		spin_unlock(&cfids->cfid_list_lock);
		return NULL;
	}
	cfid->cfids = cfids;
	cfids->num_entries++;
	list_add(&cfid->entry, &cfids->entries);
	cfid->on_list = true;
	kref_get(&cfid->refcount);
	spin_unlock(&cfids->cfid_list_lock);
	return cfid;
}

static struct dentry *
path_to_dentry(struct cifs_sb_info *cifs_sb, const char *path)
{
	struct dentry *dentry;
	const char *s, *p;
	char sep;

	sep = CIFS_DIR_SEP(cifs_sb);
	dentry = dget(cifs_sb->root);
	s = path;

	do {
		struct inode *dir = d_inode(dentry);
		struct dentry *child;

		if (!S_ISDIR(dir->i_mode)) {
			dput(dentry);
			dentry = ERR_PTR(-ENOTDIR);
			break;
		}

		/* skip separators */
		while (*s == sep)
			s++;
		if (!*s)
			break;
		p = s++;
		/* next separator */
		while (*s && *s != sep)
			s++;

		child = lookup_positive_unlocked(p, dentry, s - p);
		dput(dentry);
		dentry = child;
	} while (!IS_ERR(dentry));
	return dentry;
}

/*
 * Open the and cache a directory handle.
 * If error then *cfid is not initialized.
 */
int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon,
		    const char *path,
		    struct cifs_sb_info *cifs_sb,
		    bool lookup_only, struct cached_fid **ret_cfid)
{
	struct cifs_ses *ses;
	struct TCP_Server_Info *server;
	struct cifs_open_parms oparms;
	struct smb2_create_rsp *o_rsp = NULL;
	struct smb2_query_info_rsp *qi_rsp = NULL;
	int resp_buftype[2];
	struct smb_rqst rqst[2];
	struct kvec rsp_iov[2];
	struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
	struct kvec qi_iov[1];
	int rc, flags = 0;
	__le16 *utf16_path = NULL;
	u8 oplock = SMB2_OPLOCK_LEVEL_II;
	struct cifs_fid *pfid;
	struct dentry *dentry = NULL;
	struct cached_fid *cfid;
	struct cached_fids *cfids;

	if (tcon == NULL || tcon->cfids == NULL || tcon->nohandlecache ||
	    is_smb1_server(tcon->ses->server))
		return -EOPNOTSUPP;

	ses = tcon->ses;
	server = ses->server;
	cfids = tcon->cfids;

	if (!server->ops->new_lease_key)
		return -EIO;

	if (cifs_sb->root == NULL)
		return -ENOENT;

	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
	if (!utf16_path)
		return -ENOMEM;

	cfid = find_or_create_cached_dir(cfids, path, lookup_only);
	if (cfid == NULL) {
		kfree(utf16_path);
		return -ENOENT;
	}
	/*
	 * At this point we either have a lease already and we can just
	 * return it. If not we are guaranteed to be the only thread accessing
	 * this cfid.
	 */
	if (cfid->has_lease) {
		*ret_cfid = cfid;
		kfree(utf16_path);
		return 0;
	}

	/*
	 * We do not hold the lock for the open because in case
	 * SMB2_open needs to reconnect.
	 * This is safe because no other thread will be able to get a ref
	 * to the cfid until we have finished opening the file and (possibly)
	 * acquired a lease.
	 */
	if (smb3_encryption_required(tcon))
		flags |= CIFS_TRANSFORM_REQ;

	pfid = &cfid->fid;
	server->ops->new_lease_key(pfid);

	memset(rqst, 0, sizeof(rqst));
	resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER;
	memset(rsp_iov, 0, sizeof(rsp_iov));

	/* Open */
	memset(&open_iov, 0, sizeof(open_iov));
	rqst[0].rq_iov = open_iov;
	rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

	oparms.tcon = tcon;
	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_FILE);
	oparms.desired_access = FILE_READ_ATTRIBUTES;
	oparms.disposition = FILE_OPEN;
	oparms.fid = pfid;
	oparms.reconnect = false;

	rc = SMB2_open_init(tcon, server,
			    &rqst[0], &oplock, &oparms, utf16_path);
	if (rc)
		goto oshr_free;
	smb2_set_next_command(tcon, &rqst[0]);

	memset(&qi_iov, 0, sizeof(qi_iov));
	rqst[1].rq_iov = qi_iov;
	rqst[1].rq_nvec = 1;

	rc = SMB2_query_info_init(tcon, server,
				  &rqst[1], COMPOUND_FID,
				  COMPOUND_FID, FILE_ALL_INFORMATION,
				  SMB2_O_INFO_FILE, 0,
				  sizeof(struct smb2_file_all_info) +
				  PATH_MAX * 2, 0, NULL);
	if (rc)
		goto oshr_free;

	smb2_set_related(&rqst[1]);

	rc = compound_send_recv(xid, ses, server,
				flags, 2, rqst,
				resp_buftype, rsp_iov);
	if (rc) {
		if (rc == -EREMCHG) {
			tcon->need_reconnect = true;
			pr_warn_once("server share %s deleted\n",
				     tcon->tree_name);
		}
		goto oshr_free;
	}

	atomic_inc(&tcon->num_remote_opens);

	o_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
	oparms.fid->persistent_fid = o_rsp->PersistentFileId;
	oparms.fid->volatile_fid = o_rsp->VolatileFileId;
#ifdef CONFIG_CIFS_DEBUG2
	oparms.fid->mid = le64_to_cpu(o_rsp->hdr.MessageId);
#endif /* CIFS_DEBUG2 */

	if (o_rsp->OplockLevel != SMB2_OPLOCK_LEVEL_LEASE)
		goto oshr_free;


	smb2_parse_contexts(server, o_rsp,
			    &oparms.fid->epoch,
			    oparms.fid->lease_key, &oplock,
			    NULL, NULL);

	qi_rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
	if (le32_to_cpu(qi_rsp->OutputBufferLength) < sizeof(struct smb2_file_all_info))
		goto oshr_free;
	if (!smb2_validate_and_copy_iov(
				le16_to_cpu(qi_rsp->OutputBufferOffset),
				sizeof(struct smb2_file_all_info),
				&rsp_iov[1], sizeof(struct smb2_file_all_info),
				(char *)&cfid->file_all_info))
		cfid->file_all_info_is_valid = true;

	if (!path[0])
		dentry = dget(cifs_sb->root);
	else {
		dentry = path_to_dentry(cifs_sb, path);
		if (IS_ERR(dentry)) {
			rc = -ENOENT;
			goto oshr_free;
		}
	}
	cfid->dentry = dentry;
	cfid->tcon = tcon;
	cfid->time = jiffies;
	cfid->is_open = true;
	cfid->has_lease = true;

oshr_free:
	kfree(utf16_path);
	SMB2_open_free(&rqst[0]);
	SMB2_query_info_free(&rqst[1]);
	free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
	free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
	spin_lock(&cfids->cfid_list_lock);
	if (!cfid->has_lease) {
		if (cfid->on_list) {
			list_del(&cfid->entry);
			cfid->on_list = false;
			cfids->num_entries--;
		}
		rc = -ENOENT;
	}
	spin_unlock(&cfids->cfid_list_lock);
	if (rc) {
		free_cached_dir(cfid);
		cfid = NULL;
	}

	if (rc == 0)
		*ret_cfid = cfid;

	return rc;
}

int open_cached_dir_by_dentry(struct cifs_tcon *tcon,
			      struct dentry *dentry,
			      struct cached_fid **ret_cfid)
{
	struct cached_fid *cfid;
	struct cached_fids *cfids = tcon->cfids;

	if (cfids == NULL)
		return -ENOENT;

	spin_lock(&cfids->cfid_list_lock);
	list_for_each_entry(cfid, &cfids->entries, entry) {
		if (dentry && cfid->dentry == dentry) {
			cifs_dbg(FYI, "found a cached root file handle by dentry\n");
			kref_get(&cfid->refcount);
			*ret_cfid = cfid;
			spin_unlock(&cfids->cfid_list_lock);
			return 0;
		}
	}
	spin_unlock(&cfids->cfid_list_lock);
	return -ENOENT;
}

static void
smb2_close_cached_fid(struct kref *ref)
{
	struct cached_fid *cfid = container_of(ref, struct cached_fid,
					       refcount);

	spin_lock(&cfid->cfids->cfid_list_lock);
	if (cfid->on_list) {
		list_del(&cfid->entry);
		cfid->on_list = false;
		cfid->cfids->num_entries--;
	}
	spin_unlock(&cfid->cfids->cfid_list_lock);

	dput(cfid->dentry);
	cfid->dentry = NULL;

	if (cfid->is_open) {
		SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid,
			   cfid->fid.volatile_fid);
	}

	free_cached_dir(cfid);
}

void drop_cached_dir_by_name(const unsigned int xid, struct cifs_tcon *tcon,
			     const char *name, struct cifs_sb_info *cifs_sb)
{
	struct cached_fid *cfid = NULL;
	int rc;

	rc = open_cached_dir(xid, tcon, name, cifs_sb, true, &cfid);
	if (rc) {
		cifs_dbg(FYI, "no cached dir found for rmdir(%s)\n", name);
		return;
	}
	spin_lock(&cfid->cfids->cfid_list_lock);
	if (cfid->has_lease) {
		cfid->has_lease = false;
		kref_put(&cfid->refcount, smb2_close_cached_fid);
	}
	spin_unlock(&cfid->cfids->cfid_list_lock);
	close_cached_dir(cfid);
}


void close_cached_dir(struct cached_fid *cfid)
{
	kref_put(&cfid->refcount, smb2_close_cached_fid);
}

/*
 * Called from cifs_kill_sb when we unmount a share
 */
void close_all_cached_dirs(struct cifs_sb_info *cifs_sb)
{
	struct rb_root *root = &cifs_sb->tlink_tree;
	struct rb_node *node;
	struct cached_fid *cfid;
	struct cifs_tcon *tcon;
	struct tcon_link *tlink;
	struct cached_fids *cfids;

	for (node = rb_first(root); node; node = rb_next(node)) {
		tlink = rb_entry(node, struct tcon_link, tl_rbnode);
		tcon = tlink_tcon(tlink);
		if (IS_ERR(tcon))
			continue;
		cfids = tcon->cfids;
		if (cfids == NULL)
			continue;
		list_for_each_entry(cfid, &cfids->entries, entry) {
			dput(cfid->dentry);
			cfid->dentry = NULL;
		}
	}
}

/*
 * Invalidate all cached dirs when a TCON has been reset
 * due to a session loss.
 */
void invalidate_all_cached_dirs(struct cifs_tcon *tcon)
{
	struct cached_fids *cfids = tcon->cfids;
	struct cached_fid *cfid, *q;
	LIST_HEAD(entry);

	spin_lock(&cfids->cfid_list_lock);
	list_for_each_entry_safe(cfid, q, &cfids->entries, entry) {
		list_move(&cfid->entry, &entry);
		cfids->num_entries--;
		cfid->is_open = false;
		cfid->on_list = false;
		/* To prevent race with smb2_cached_lease_break() */
		kref_get(&cfid->refcount);
	}
	spin_unlock(&cfids->cfid_list_lock);

	list_for_each_entry_safe(cfid, q, &entry, entry) {
		list_del(&cfid->entry);
		cancel_work_sync(&cfid->lease_break);
		if (cfid->has_lease) {
			/*
			 * We lease was never cancelled from the server so we
			 * need to drop the reference.
			 */
			spin_lock(&cfids->cfid_list_lock);
			cfid->has_lease = false;
			spin_unlock(&cfids->cfid_list_lock);
			kref_put(&cfid->refcount, smb2_close_cached_fid);
		}
		/* Drop the extra reference opened above*/
		kref_put(&cfid->refcount, smb2_close_cached_fid);
	}
}

static void
smb2_cached_lease_break(struct work_struct *work)
{
	struct cached_fid *cfid = container_of(work,
				struct cached_fid, lease_break);

	spin_lock(&cfid->cfids->cfid_list_lock);
	cfid->has_lease = false;
	spin_unlock(&cfid->cfids->cfid_list_lock);
	kref_put(&cfid->refcount, smb2_close_cached_fid);
}

int cached_dir_lease_break(struct cifs_tcon *tcon, __u8 lease_key[16])
{
	struct cached_fids *cfids = tcon->cfids;
	struct cached_fid *cfid;

	if (cfids == NULL)
		return false;

	spin_lock(&cfids->cfid_list_lock);
	list_for_each_entry(cfid, &cfids->entries, entry) {
		if (cfid->has_lease &&
		    !memcmp(lease_key,
			    cfid->fid.lease_key,
			    SMB2_LEASE_KEY_SIZE)) {
			cfid->time = 0;
			/*
			 * We found a lease remove it from the list
			 * so no threads can access it.
			 */
			list_del(&cfid->entry);
			cfid->on_list = false;
			cfids->num_entries--;

			queue_work(cifsiod_wq,
				   &cfid->lease_break);
			spin_unlock(&cfids->cfid_list_lock);
			return true;
		}
	}
	spin_unlock(&cfids->cfid_list_lock);
	return false;
}

static struct cached_fid *init_cached_dir(const char *path)
{
	struct cached_fid *cfid;

	cfid = kzalloc(sizeof(*cfid), GFP_ATOMIC);
	if (!cfid)
		return NULL;
	cfid->path = kstrdup(path, GFP_ATOMIC);
	if (!cfid->path) {
		kfree(cfid);
		return NULL;
	}

	INIT_WORK(&cfid->lease_break, smb2_cached_lease_break);
	INIT_LIST_HEAD(&cfid->entry);
	INIT_LIST_HEAD(&cfid->dirents.entries);
	mutex_init(&cfid->dirents.de_mutex);
	spin_lock_init(&cfid->fid_lock);
	kref_init(&cfid->refcount);
	return cfid;
}

static void free_cached_dir(struct cached_fid *cfid)
{
	struct cached_dirent *dirent, *q;

	dput(cfid->dentry);
	cfid->dentry = NULL;

	/*
	 * Delete all cached dirent names
	 */
	list_for_each_entry_safe(dirent, q, &cfid->dirents.entries, entry) {
		list_del(&dirent->entry);
		kfree(dirent->name);
		kfree(dirent);
	}

	kfree(cfid->path);
	cfid->path = NULL;
	kfree(cfid);
}

struct cached_fids *init_cached_dirs(void)
{
	struct cached_fids *cfids;

	cfids = kzalloc(sizeof(*cfids), GFP_KERNEL);
	if (!cfids)
		return NULL;
	spin_lock_init(&cfids->cfid_list_lock);
	INIT_LIST_HEAD(&cfids->entries);
	return cfids;
}

/*
 * Called from tconInfoFree when we are tearing down the tcon.
 * There are no active users or open files/directories at this point.
 */
void free_cached_dirs(struct cached_fids *cfids)
{
	struct cached_fid *cfid, *q;
	LIST_HEAD(entry);

	spin_lock(&cfids->cfid_list_lock);
	list_for_each_entry_safe(cfid, q, &cfids->entries, entry) {
		cfid->on_list = false;
		cfid->is_open = false;
		list_move(&cfid->entry, &entry);
	}
	spin_unlock(&cfids->cfid_list_lock);

	list_for_each_entry_safe(cfid, q, &entry, entry) {
		list_del(&cfid->entry);
		free_cached_dir(cfid);
	}

	kfree(cfids);
}
Commit	Line	Data
05b98fd2 RS	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* Functions to handle the cached directory entries
	4	*
	5	* Copyright (c) 2022, Ronnie Sahlberg <lsahlber@redhat.com>
	6	*/
	7
e4029e07	8	#include <linux/namei.h>
05b98fd2 RS	9	#include "cifsglob.h"
	10	#include "cifsproto.h"
	11	#include "cifs_debug.h"
	12	#include "smb2proto.h"
	13	#include "cached_dir.h"
	14
ebe98f14 RS	15	static struct cached_fid init_cached_dir(const char path);
	16	static void free_cached_dir(struct cached_fid *cfid);
	17
	18	static struct cached_fid find_or_create_cached_dir(struct cached_fids cfids,
	19	const char *path,
	20	bool lookup_only)
	21	{
	22	struct cached_fid *cfid;
	23
	24	spin_lock(&cfids->cfid_list_lock);
	25	list_for_each_entry(cfid, &cfids->entries, entry) {
	26	if (!strcmp(cfid->path, path)) {
	27	/*
	28	* If it doesn't have a lease it is either not yet
	29	* fully cached or it may be in the process of
	30	* being deleted due to a lease break.
	31	*/
	32	if (!cfid->has_lease) {
	33	spin_unlock(&cfids->cfid_list_lock);
	34	return NULL;
	35	}
	36	kref_get(&cfid->refcount);
	37	spin_unlock(&cfids->cfid_list_lock);
	38	return cfid;
	39	}
	40	}
	41	if (lookup_only) {
	42	spin_unlock(&cfids->cfid_list_lock);
	43	return NULL;
	44	}
	45	if (cfids->num_entries >= MAX_CACHED_FIDS) {
	46	spin_unlock(&cfids->cfid_list_lock);
	47	return NULL;
	48	}
	49	cfid = init_cached_dir(path);
	50	if (cfid == NULL) {
	51	spin_unlock(&cfids->cfid_list_lock);
	52	return NULL;
	53	}
	54	cfid->cfids = cfids;
	55	cfids->num_entries++;
	56	list_add(&cfid->entry, &cfids->entries);
	57	cfid->on_list = true;
	58	kref_get(&cfid->refcount);
	59	spin_unlock(&cfids->cfid_list_lock);
	60	return cfid;
	61	}
30f8f371	62
e4029e07 RS	63	static struct dentry *
	64	path_to_dentry(struct cifs_sb_info cifs_sb, const char path)
	65	{
	66	struct dentry *dentry;
	67	const char s, p;
	68	char sep;
	69
	70	sep = CIFS_DIR_SEP(cifs_sb);
	71	dentry = dget(cifs_sb->root);
	72	s = path;
	73
	74	do {
	75	struct inode *dir = d_inode(dentry);
	76	struct dentry *child;
	77
	78	if (!S_ISDIR(dir->i_mode)) {
	79	dput(dentry);
	80	dentry = ERR_PTR(-ENOTDIR);
	81	break;
	82	}
	83
	84	/* skip separators */
	85	while (*s == sep)
	86	s++;
	87	if (!*s)
	88	break;
	89	p = s++;
	90	/* next separator */
	91	while (s && s != sep)
	92	s++;
	93
	94	child = lookup_positive_unlocked(p, dentry, s - p);
	95	dput(dentry);
	96	dentry = child;
	97	} while (!IS_ERR(dentry));
	98	return dentry;
	99	}
	100
05b98fd2 RS	101	/*
	102	* Open the and cache a directory handle.
	103	* If error then *cfid is not initialized.
	104	*/
	105	int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon,
7eb59a98 RS	106	const char *path,
	107	struct cifs_sb_info *cifs_sb,
	108	bool lookup_only, struct cached_fid **ret_cfid)
05b98fd2 RS	109	{
	110	struct cifs_ses *ses;
	111	struct TCP_Server_Info *server;
	112	struct cifs_open_parms oparms;
	113	struct smb2_create_rsp *o_rsp = NULL;
	114	struct smb2_query_info_rsp *qi_rsp = NULL;
	115	int resp_buftype[2];
	116	struct smb_rqst rqst[2];
	117	struct kvec rsp_iov[2];
	118	struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
	119	struct kvec qi_iov[1];
	120	int rc, flags = 0;
ebe98f14	121	__le16 *utf16_path = NULL;
05b98fd2 RS	122	u8 oplock = SMB2_OPLOCK_LEVEL_II;
05b98fd2 RS	123	struct cifs_fid *pfid;
ebe98f14	124	struct dentry *dentry = NULL;
a63ec83c	125	struct cached_fid *cfid;
ebe98f14	126	struct cached_fids *cfids;
05b98fd2	127
ebe98f14	128	if (tcon == NULL \|\| tcon->cfids == NULL \|\| tcon->nohandlecache \|\|
05b98fd2 RS	129	is_smb1_server(tcon->ses->server))
	130	return -EOPNOTSUPP;
	131
	132	ses = tcon->ses;
	133	server = ses->server;
ebe98f14 RS	134	cfids = tcon->cfids;
	135
	136	if (!server->ops->new_lease_key)
	137	return -EIO;
05b98fd2 RS	138
	139	if (cifs_sb->root == NULL)
	140	return -ENOENT;
	141
ebe98f14 RS	142	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
ebe98f14 RS	143	if (!utf16_path)
30f8f371 RS	144	return -ENOMEM;
30f8f371 RS	145
ebe98f14 RS	146	cfid = find_or_create_cached_dir(cfids, path, lookup_only);
	147	if (cfid == NULL) {
	148	kfree(utf16_path);
	149	return -ENOENT;
	150	}
	151	/*
	152	* At this point we either have a lease already and we can just
	153	* return it. If not we are guaranteed to be the only thread accessing
	154	* this cfid.
	155	*/
	156	if (cfid->has_lease) {
a63ec83c	157	*ret_cfid = cfid;
ebe98f14	158	kfree(utf16_path);
05b98fd2 RS	159	return 0;
	160	}
	161
	162	/*
	163	* We do not hold the lock for the open because in case
ebe98f14 RS	164	* SMB2_open needs to reconnect.
	165	* This is safe because no other thread will be able to get a ref
	166	* to the cfid until we have finished opening the file and (possibly)
	167	* acquired a lease.
05b98fd2	168	*/
05b98fd2 RS	169	if (smb3_encryption_required(tcon))
	170	flags \|= CIFS_TRANSFORM_REQ;
	171
a63ec83c	172	pfid = &cfid->fid;
05b98fd2 RS	173	server->ops->new_lease_key(pfid);
	174
	175	memset(rqst, 0, sizeof(rqst));
	176	resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER;
	177	memset(rsp_iov, 0, sizeof(rsp_iov));
	178
	179	/* Open */
	180	memset(&open_iov, 0, sizeof(open_iov));
	181	rqst[0].rq_iov = open_iov;
	182	rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;
	183
	184	oparms.tcon = tcon;
	185	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_FILE);
	186	oparms.desired_access = FILE_READ_ATTRIBUTES;
	187	oparms.disposition = FILE_OPEN;
	188	oparms.fid = pfid;
	189	oparms.reconnect = false;
	190
	191	rc = SMB2_open_init(tcon, server,
ebe98f14	192	&rqst[0], &oplock, &oparms, utf16_path);
05b98fd2 RS	193	if (rc)
	194	goto oshr_free;
	195	smb2_set_next_command(tcon, &rqst[0]);
	196
	197	memset(&qi_iov, 0, sizeof(qi_iov));
	198	rqst[1].rq_iov = qi_iov;
	199	rqst[1].rq_nvec = 1;
	200
	201	rc = SMB2_query_info_init(tcon, server,
	202	&rqst[1], COMPOUND_FID,
	203	COMPOUND_FID, FILE_ALL_INFORMATION,
	204	SMB2_O_INFO_FILE, 0,
	205	sizeof(struct smb2_file_all_info) +
	206	PATH_MAX * 2, 0, NULL);
	207	if (rc)
	208	goto oshr_free;
	209
	210	smb2_set_related(&rqst[1]);
	211
	212	rc = compound_send_recv(xid, ses, server,
	213	flags, 2, rqst,
	214	resp_buftype, rsp_iov);
05b98fd2 RS	215	if (rc) {
	216	if (rc == -EREMCHG) {
	217	tcon->need_reconnect = true;
	218	pr_warn_once("server share %s deleted\n",
68e14569	219	tcon->tree_name);
05b98fd2	220	}
ebe98f14	221	goto oshr_free;
05b98fd2 RS	222	}
	223
	224	atomic_inc(&tcon->num_remote_opens);
	225
	226	o_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
	227	oparms.fid->persistent_fid = o_rsp->PersistentFileId;
	228	oparms.fid->volatile_fid = o_rsp->VolatileFileId;
	229	#ifdef CONFIG_CIFS_DEBUG2
	230	oparms.fid->mid = le64_to_cpu(o_rsp->hdr.MessageId);
	231	#endif /* CIFS_DEBUG2 */
	232
ebe98f14 RS	233	if (o_rsp->OplockLevel != SMB2_OPLOCK_LEVEL_LEASE)
	234	goto oshr_free;
	235
	236
	237	smb2_parse_contexts(server, o_rsp,
	238	&oparms.fid->epoch,
	239	oparms.fid->lease_key, &oplock,
	240	NULL, NULL);
05b98fd2 RS	241
	242	qi_rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
	243	if (le32_to_cpu(qi_rsp->OutputBufferLength) < sizeof(struct smb2_file_all_info))
ebe98f14	244	goto oshr_free;
05b98fd2 RS	245	if (!smb2_validate_and_copy_iov(
	246	le16_to_cpu(qi_rsp->OutputBufferOffset),
	247	sizeof(struct smb2_file_all_info),
	248	&rsp_iov[1], sizeof(struct smb2_file_all_info),
a63ec83c RS	249	(char *)&cfid->file_all_info))
a63ec83c RS	250	cfid->file_all_info_is_valid = true;
e4029e07 RS	251
	252	if (!path[0])
	253	dentry = dget(cifs_sb->root);
	254	else {
	255	dentry = path_to_dentry(cifs_sb, path);
053569cc RS	256	if (IS_ERR(dentry)) {
053569cc RS	257	rc = -ENOENT;
e4029e07	258	goto oshr_free;
053569cc	259	}
e4029e07 RS	260	}
	261	cfid->dentry = dentry;
	262	cfid->tcon = tcon;
a63ec83c	263	cfid->time = jiffies;
ebe98f14 RS	264	cfid->is_open = true;
ebe98f14 RS	265	cfid->has_lease = true;
05b98fd2	266
05b98fd2	267	oshr_free:
ebe98f14	268	kfree(utf16_path);
05b98fd2 RS	269	SMB2_open_free(&rqst[0]);
	270	SMB2_query_info_free(&rqst[1]);
	271	free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
	272	free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
ebe98f14 RS	273	spin_lock(&cfids->cfid_list_lock);
	274	if (!cfid->has_lease) {
	275	if (cfid->on_list) {
	276	list_del(&cfid->entry);
	277	cfid->on_list = false;
	278	cfids->num_entries--;
	279	}
	280	rc = -ENOENT;
	281	}
	282	spin_unlock(&cfids->cfid_list_lock);
	283	if (rc) {
	284	free_cached_dir(cfid);
	285	cfid = NULL;
	286	}
	287
05b98fd2	288	if (rc == 0)
a63ec83c	289	*ret_cfid = cfid;
05b98fd2 RS	290
	291	return rc;
	292	}
	293
	294	int open_cached_dir_by_dentry(struct cifs_tcon *tcon,
	295	struct dentry *dentry,
a63ec83c	296	struct cached_fid **ret_cfid)
05b98fd2	297	{
a63ec83c	298	struct cached_fid *cfid;
ebe98f14	299	struct cached_fids *cfids = tcon->cfids;
a63ec83c	300
ebe98f14	301	if (cfids == NULL)
30f8f371	302	return -ENOENT;
a63ec83c	303
ebe98f14 RS	304	spin_lock(&cfids->cfid_list_lock);
	305	list_for_each_entry(cfid, &cfids->entries, entry) {
	306	if (dentry && cfid->dentry == dentry) {
	307	cifs_dbg(FYI, "found a cached root file handle by dentry\n");
	308	kref_get(&cfid->refcount);
	309	*ret_cfid = cfid;
	310	spin_unlock(&cfids->cfid_list_lock);
	311	return 0;
	312	}
05b98fd2	313	}
ebe98f14	314	spin_unlock(&cfids->cfid_list_lock);
05b98fd2 RS	315	return -ENOENT;
	316	}
	317
	318	static void
	319	smb2_close_cached_fid(struct kref *ref)
	320	{
	321	struct cached_fid *cfid = container_of(ref, struct cached_fid,
	322	refcount);
05b98fd2	323
ebe98f14 RS	324	spin_lock(&cfid->cfids->cfid_list_lock);
	325	if (cfid->on_list) {
	326	list_del(&cfid->entry);
	327	cfid->on_list = false;
	328	cfid->cfids->num_entries--;
05b98fd2	329	}
ebe98f14	330	spin_unlock(&cfid->cfids->cfid_list_lock);
05b98fd2	331
ebe98f14 RS	332	dput(cfid->dentry);
	333	cfid->dentry = NULL;
	334
	335	if (cfid->is_open) {
	336	SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid,
	337	cfid->fid.volatile_fid);
05b98fd2	338	}
05b98fd2	339
ebe98f14	340	free_cached_dir(cfid);
05b98fd2 RS	341	}
05b98fd2 RS	342
8e77860c RS	343	void drop_cached_dir_by_name(const unsigned int xid, struct cifs_tcon *tcon,
	344	const char name, struct cifs_sb_info cifs_sb)
	345	{
	346	struct cached_fid *cfid = NULL;
	347	int rc;
	348
	349	rc = open_cached_dir(xid, tcon, name, cifs_sb, true, &cfid);
	350	if (rc) {
	351	cifs_dbg(FYI, "no cached dir found for rmdir(%s)\n", name);
	352	return;
	353	}
	354	spin_lock(&cfid->cfids->cfid_list_lock);
	355	if (cfid->has_lease) {
	356	cfid->has_lease = false;
	357	kref_put(&cfid->refcount, smb2_close_cached_fid);
	358	}
	359	spin_unlock(&cfid->cfids->cfid_list_lock);
	360	close_cached_dir(cfid);
	361	}
	362
	363
05b98fd2 RS	364	void close_cached_dir(struct cached_fid *cfid)
05b98fd2 RS	365	{
05b98fd2	366	kref_put(&cfid->refcount, smb2_close_cached_fid);
05b98fd2 RS	367	}
	368
	369	/*
	370	* Called from cifs_kill_sb when we unmount a share
	371	*/
	372	void close_all_cached_dirs(struct cifs_sb_info *cifs_sb)
	373	{
	374	struct rb_root *root = &cifs_sb->tlink_tree;
	375	struct rb_node *node;
	376	struct cached_fid *cfid;
	377	struct cifs_tcon *tcon;
	378	struct tcon_link *tlink;
ebe98f14	379	struct cached_fids *cfids;
05b98fd2 RS	380
	381	for (node = rb_first(root); node; node = rb_next(node)) {
	382	tlink = rb_entry(node, struct tcon_link, tl_rbnode);
	383	tcon = tlink_tcon(tlink);
	384	if (IS_ERR(tcon))
	385	continue;
ebe98f14 RS	386	cfids = tcon->cfids;
ebe98f14 RS	387	if (cfids == NULL)
30f8f371	388	continue;
ebe98f14	389	list_for_each_entry(cfid, &cfids->entries, entry) {
05b98fd2 RS	390	dput(cfid->dentry);
	391	cfid->dentry = NULL;
	392	}
05b98fd2 RS	393	}
	394	}
	395
	396	/*
ebe98f14	397	* Invalidate all cached dirs when a TCON has been reset
05b98fd2 RS	398	* due to a session loss.
	399	*/
	400	void invalidate_all_cached_dirs(struct cifs_tcon *tcon)
	401	{
ebe98f14 RS	402	struct cached_fids *cfids = tcon->cfids;
ebe98f14 RS	403	struct cached_fid cfid, q;
d32f211a	404	LIST_HEAD(entry);
ebe98f14	405
ebe98f14 RS	406	spin_lock(&cfids->cfid_list_lock);
ebe98f14 RS	407	list_for_each_entry_safe(cfid, q, &cfids->entries, entry) {
d32f211a	408	list_move(&cfid->entry, &entry);
ebe98f14 RS	409	cfids->num_entries--;
ebe98f14 RS	410	cfid->is_open = false;
053569cc	411	cfid->on_list = false;
ebe98f14 RS	412	/* To prevent race with smb2_cached_lease_break() */
	413	kref_get(&cfid->refcount);
	414	}
	415	spin_unlock(&cfids->cfid_list_lock);
	416
	417	list_for_each_entry_safe(cfid, q, &entry, entry) {
ebe98f14 RS	418	list_del(&cfid->entry);
	419	cancel_work_sync(&cfid->lease_break);
	420	if (cfid->has_lease) {
	421	/*
	422	* We lease was never cancelled from the server so we
	423	* need to drop the reference.
	424	*/
	425	spin_lock(&cfids->cfid_list_lock);
	426	cfid->has_lease = false;
	427	spin_unlock(&cfids->cfid_list_lock);
	428	kref_put(&cfid->refcount, smb2_close_cached_fid);
	429	}
	430	/* Drop the extra reference opened above*/
	431	kref_put(&cfid->refcount, smb2_close_cached_fid);
	432	}
05b98fd2 RS	433	}
	434
	435	static void
	436	smb2_cached_lease_break(struct work_struct *work)
	437	{
	438	struct cached_fid *cfid = container_of(work,
	439	struct cached_fid, lease_break);
	440
ebe98f14 RS	441	spin_lock(&cfid->cfids->cfid_list_lock);
	442	cfid->has_lease = false;
	443	spin_unlock(&cfid->cfids->cfid_list_lock);
	444	kref_put(&cfid->refcount, smb2_close_cached_fid);
05b98fd2 RS	445	}
	446
	447	int cached_dir_lease_break(struct cifs_tcon *tcon, __u8 lease_key[16])
	448	{
ebe98f14 RS	449	struct cached_fids *cfids = tcon->cfids;
ebe98f14 RS	450	struct cached_fid *cfid;
30f8f371	451
ebe98f14	452	if (cfids == NULL)
30f8f371	453	return false;
aea6794e	454
ebe98f14 RS	455	spin_lock(&cfids->cfid_list_lock);
	456	list_for_each_entry(cfid, &cfids->entries, entry) {
	457	if (cfid->has_lease &&
	458	!memcmp(lease_key,
	459	cfid->fid.lease_key,
	460	SMB2_LEASE_KEY_SIZE)) {
	461	cfid->time = 0;
	462	/*
	463	* We found a lease remove it from the list
	464	* so no threads can access it.
	465	*/
	466	list_del(&cfid->entry);
	467	cfid->on_list = false;
	468	cfids->num_entries--;
	469
	470	queue_work(cifsiod_wq,
	471	&cfid->lease_break);
	472	spin_unlock(&cfids->cfid_list_lock);
	473	return true;
	474	}
05b98fd2	475	}
ebe98f14	476	spin_unlock(&cfids->cfid_list_lock);
05b98fd2 RS	477	return false;
05b98fd2 RS	478	}
a63ec83c	479
ebe98f14	480	static struct cached_fid init_cached_dir(const char path)
30f8f371 RS	481	{
	482	struct cached_fid *cfid;
	483
ebe98f14	484	cfid = kzalloc(sizeof(*cfid), GFP_ATOMIC);
30f8f371 RS	485	if (!cfid)
30f8f371 RS	486	return NULL;
ebe98f14	487	cfid->path = kstrdup(path, GFP_ATOMIC);
30f8f371 RS	488	if (!cfid->path) {
	489	kfree(cfid);
	490	return NULL;
	491	}
	492
ebe98f14 RS	493	INIT_WORK(&cfid->lease_break, smb2_cached_lease_break);
ebe98f14 RS	494	INIT_LIST_HEAD(&cfid->entry);
30f8f371 RS	495	INIT_LIST_HEAD(&cfid->dirents.entries);
30f8f371 RS	496	mutex_init(&cfid->dirents.de_mutex);
ebe98f14 RS	497	spin_lock_init(&cfid->fid_lock);
ebe98f14 RS	498	kref_init(&cfid->refcount);
30f8f371 RS	499	return cfid;
	500	}
	501
ebe98f14	502	static void free_cached_dir(struct cached_fid *cfid)
30f8f371	503	{
ebe98f14 RS	504	struct cached_dirent dirent, q;
	505
	506	dput(cfid->dentry);
	507	cfid->dentry = NULL;
	508
	509	/*
	510	* Delete all cached dirent names
	511	*/
	512	list_for_each_entry_safe(dirent, q, &cfid->dirents.entries, entry) {
	513	list_del(&dirent->entry);
	514	kfree(dirent->name);
	515	kfree(dirent);
	516	}
	517
30f8f371 RS	518	kfree(cfid->path);
	519	cfid->path = NULL;
	520	kfree(cfid);
	521	}
	522
aea6794e	523	struct cached_fids *init_cached_dirs(void)
a63ec83c	524	{
aea6794e	525	struct cached_fids *cfids;
a63ec83c	526
aea6794e RS	527	cfids = kzalloc(sizeof(*cfids), GFP_KERNEL);
aea6794e RS	528	if (!cfids)
a63ec83c	529	return NULL;
ebe98f14 RS	530	spin_lock_init(&cfids->cfid_list_lock);
ebe98f14 RS	531	INIT_LIST_HEAD(&cfids->entries);
aea6794e	532	return cfids;
a63ec83c RS	533	}
a63ec83c RS	534
ebe98f14 RS	535	/*
	536	* Called from tconInfoFree when we are tearing down the tcon.
	537	* There are no active users or open files/directories at this point.
	538	*/
aea6794e	539	void free_cached_dirs(struct cached_fids *cfids)
a63ec83c	540	{
ebe98f14	541	struct cached_fid cfid, q;
d32f211a	542	LIST_HEAD(entry);
ebe98f14	543
ebe98f14 RS	544	spin_lock(&cfids->cfid_list_lock);
	545	list_for_each_entry_safe(cfid, q, &cfids->entries, entry) {
	546	cfid->on_list = false;
	547	cfid->is_open = false;
d32f211a	548	list_move(&cfid->entry, &entry);
30f8f371	549	}
ebe98f14 RS	550	spin_unlock(&cfids->cfid_list_lock);
	551
	552	list_for_each_entry_safe(cfid, q, &entry, entry) {
	553	list_del(&cfid->entry);
	554	free_cached_dir(cfid);
	555	}
	556
aea6794e	557	kfree(cfids);
a63ec83c	558	}