diff options
Diffstat (limited to 'fs/smb/client/cached_dir.c')
| -rw-r--r-- | fs/smb/client/cached_dir.c | 862 |
1 files changed, 862 insertions, 0 deletions
diff --git a/fs/smb/client/cached_dir.c b/fs/smb/client/cached_dir.c new file mode 100644 index 000000000000..1db7ab6c2529 --- /dev/null +++ b/fs/smb/client/cached_dir.c @@ -0,0 +1,862 @@ +// 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 void smb2_close_cached_fid(struct kref *ref); +static void cfids_laundromat_worker(struct work_struct *work); +static void close_cached_dir_locked(struct cached_fid *cfid); + +struct cached_dir_dentry { + struct list_head entry; + struct dentry *dentry; +}; + +static struct cached_fid *find_or_create_cached_dir(struct cached_fids *cfids, + const char *path, + bool lookup_only, + __u32 max_cached_dirs) +{ + struct cached_fid *cfid; + + 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 (!is_valid_cached_dir(cfid)) + return NULL; + kref_get(&cfid->refcount); + return cfid; + } + } + if (lookup_only) { + return NULL; + } + if (cfids->num_entries >= max_cached_dirs) { + return NULL; + } + cfid = init_cached_dir(path); + if (cfid == NULL) { + return NULL; + } + cfid->cfids = cfids; + cfids->num_entries++; + list_add(&cfid->entry, &cfids->entries); + cfid->on_list = true; + kref_get(&cfid->refcount); + /* + * Set @cfid->has_lease to true during construction so that the lease + * reference can be put in cached_dir_lease_break() due to a potential + * lease break right after the request is sent or while @cfid is still + * being cached, or if a reconnection is triggered during construction. + * Concurrent processes won't be to use it yet due to @cfid->time being + * zero. + */ + cfid->has_lease = true; + + 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_noperm_positive_unlocked(&QSTR_LEN(p, s - p), + dentry); + dput(dentry); + dentry = child; + } while (!IS_ERR(dentry)); + return dentry; +} + +static const char *path_no_prefix(struct cifs_sb_info *cifs_sb, + const char *path) +{ + size_t len = 0; + + if (!*path) + return path; + + if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) && + cifs_sb->prepath) { + len = strlen(cifs_sb->prepath) + 1; + if (unlikely(len > strlen(path))) + return ERR_PTR(-EINVAL); + } + return path + len; +} + +/* + * 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; + const char *npath; + int retries = 0, cur_sleep = 1; + __le32 lease_flags = 0; + + if (cifs_sb->root == NULL) + return -ENOENT; + + if (tcon == NULL) + return -EOPNOTSUPP; + + ses = tcon->ses; + cfids = tcon->cfids; + + if (cfids == NULL) + return -EOPNOTSUPP; + +replay_again: + /* reinitialize for possible replay */ + flags = 0; + oplock = SMB2_OPLOCK_LEVEL_II; + server = cifs_pick_channel(ses); + + if (!server->ops->new_lease_key) + return smb_EIO(smb_eio_trace_no_lease_key); + + utf16_path = cifs_convert_path_to_utf16(path, cifs_sb); + if (!utf16_path) + return -ENOMEM; + + spin_lock(&cfids->cfid_list_lock); + cfid = find_or_create_cached_dir(cfids, path, lookup_only, tcon->max_cached_dirs); + if (cfid == NULL) { + spin_unlock(&cfids->cfid_list_lock); + kfree(utf16_path); + return -ENOENT; + } + /* + * Return cached fid if it is valid (has a lease and has a time). + * Otherwise, it is either a new entry or laundromat worker removed it + * from @cfids->entries. Caller will put last reference if the latter. + */ + if (is_valid_cached_dir(cfid)) { + cfid->last_access_time = jiffies; + spin_unlock(&cfids->cfid_list_lock); + *ret_cfid = cfid; + kfree(utf16_path); + return 0; + } + spin_unlock(&cfids->cfid_list_lock); + + pfid = &cfid->fid; + + /* + * Skip any prefix paths in @path as lookup_noperm_positive_unlocked() ends up + * calling ->lookup() which already adds those through + * build_path_from_dentry(). Also, do it earlier as we might reconnect + * below when trying to send compounded request and then potentially + * having a different prefix path (e.g. after DFS failover). + */ + npath = path_no_prefix(cifs_sb, path); + if (IS_ERR(npath)) { + rc = PTR_ERR(npath); + goto out; + } + + if (!npath[0]) { + dentry = dget(cifs_sb->root); + } else { + dentry = path_to_dentry(cifs_sb, npath); + if (IS_ERR(dentry)) { + rc = -ENOENT; + goto out; + } + if (dentry->d_parent && server->dialect >= SMB30_PROT_ID) { + struct cached_fid *parent_cfid; + + spin_lock(&cfids->cfid_list_lock); + list_for_each_entry(parent_cfid, &cfids->entries, entry) { + if (parent_cfid->dentry == dentry->d_parent) { + cifs_dbg(FYI, "found a parent cached file handle\n"); + if (is_valid_cached_dir(parent_cfid)) { + lease_flags + |= SMB2_LEASE_FLAG_PARENT_LEASE_KEY_SET_LE; + memcpy(pfid->parent_lease_key, + parent_cfid->fid.lease_key, + SMB2_LEASE_KEY_SIZE); + } + break; + } + } + spin_unlock(&cfids->cfid_list_lock); + } + } + cfid->dentry = dentry; + cfid->tcon = tcon; + + /* + * 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; + + 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 = (struct cifs_open_parms) { + .tcon = tcon, + .path = path, + .create_options = cifs_create_options(cifs_sb, CREATE_NOT_FILE), + .desired_access = FILE_READ_DATA | FILE_READ_ATTRIBUTES | + FILE_READ_EA, + .disposition = FILE_OPEN, + .fid = pfid, + .lease_flags = lease_flags, + .replay = !!(retries), + }; + + 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]); + + if (retries) { + smb2_set_replay(server, &rqst[0]); + smb2_set_replay(server, &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; + } + cfid->is_open = true; + + spin_lock(&cfids->cfid_list_lock); + + 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) { + spin_unlock(&cfids->cfid_list_lock); + rc = -EINVAL; + goto oshr_free; + } + + rc = smb2_parse_contexts(server, rsp_iov, + &oparms.fid->epoch, + oparms.fid->lease_key, + &oplock, NULL, NULL); + if (rc) { + spin_unlock(&cfids->cfid_list_lock); + goto oshr_free; + } + + rc = -EINVAL; + if (!(oplock & SMB2_LEASE_READ_CACHING_HE)) { + spin_unlock(&cfids->cfid_list_lock); + goto oshr_free; + } + 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)) { + spin_unlock(&cfids->cfid_list_lock); + 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; + + cfid->time = jiffies; + cfid->last_access_time = jiffies; + spin_unlock(&cfids->cfid_list_lock); + /* At this point the directory handle is fully cached */ + rc = 0; + +oshr_free: + 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); +out: + if (rc) { + spin_lock(&cfids->cfid_list_lock); + if (cfid->on_list) { + list_del(&cfid->entry); + cfid->on_list = false; + cfids->num_entries--; + } + if (cfid->has_lease) { + /* + * We are guaranteed to have two references at this + * point. One for the caller and one for a potential + * lease. Release one here, and the second below. + */ + cfid->has_lease = false; + close_cached_dir_locked(cfid); + } + spin_unlock(&cfids->cfid_list_lock); + + close_cached_dir(cfid); + } else { + *ret_cfid = cfid; + atomic_inc(&tcon->num_remote_opens); + } + kfree(utf16_path); + + if (is_replayable_error(rc) && + smb2_should_replay(tcon, &retries, &cur_sleep)) + goto replay_again; + + 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 -EOPNOTSUPP; + + if (!dentry) + return -ENOENT; + + spin_lock(&cfids->cfid_list_lock); + list_for_each_entry(cfid, &cfids->entries, entry) { + if (cfid->dentry == dentry) { + if (!is_valid_cached_dir(cfid)) + break; + cifs_dbg(FYI, "found a cached file handle by dentry\n"); + kref_get(&cfid->refcount); + *ret_cfid = cfid; + cfid->last_access_time = jiffies; + 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) +__releases(&cfid->cfids->cfid_list_lock) +{ + struct cached_fid *cfid = container_of(ref, struct cached_fid, + refcount); + int rc; + + lockdep_assert_held(&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) { + rc = SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid, + cfid->fid.volatile_fid); + if (rc) /* should we retry on -EBUSY or -EAGAIN? */ + cifs_dbg(VFS, "close cached dir rc %d\n", rc); + } + + 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; + close_cached_dir_locked(cfid); + } + spin_unlock(&cfid->cfids->cfid_list_lock); + close_cached_dir(cfid); +} + +/** + * close_cached_dir - drop a reference of a cached dir + * + * The release function will be called with cfid_list_lock held to remove the + * cached dirs from the list before any other thread can take another @cfid + * ref. Must not be called with cfid_list_lock held; use + * close_cached_dir_locked() called instead. + * + * @cfid: cached dir + */ +void close_cached_dir(struct cached_fid *cfid) +{ + lockdep_assert_not_held(&cfid->cfids->cfid_list_lock); + kref_put_lock(&cfid->refcount, smb2_close_cached_fid, &cfid->cfids->cfid_list_lock); +} + +/** + * close_cached_dir_locked - put a reference of a cached dir with + * cfid_list_lock held + * + * Calling close_cached_dir() with cfid_list_lock held has the potential effect + * of causing a deadlock if the invariant of refcount >= 2 is false. + * + * This function is used in paths that hold cfid_list_lock and expect at least + * two references. If that invariant is violated, WARNs and returns without + * dropping a reference; the final put must still go through + * close_cached_dir(). + * + * @cfid: cached dir + */ +static void close_cached_dir_locked(struct cached_fid *cfid) +{ + lockdep_assert_held(&cfid->cfids->cfid_list_lock); + + if (WARN_ON(kref_read(&cfid->refcount) < 2)) + return; + + 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; + struct cached_dir_dentry *tmp_list, *q; + LIST_HEAD(entry); + + spin_lock(&cifs_sb->tlink_tree_lock); + 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; + spin_lock(&cfids->cfid_list_lock); + list_for_each_entry(cfid, &cfids->entries, entry) { + tmp_list = kmalloc(sizeof(*tmp_list), GFP_ATOMIC); + if (tmp_list == NULL) { + /* + * If the malloc() fails, we won't drop all + * dentries, and unmounting is likely to trigger + * a 'Dentry still in use' error. + */ + cifs_tcon_dbg(VFS, "Out of memory while dropping dentries\n"); + spin_unlock(&cfids->cfid_list_lock); + spin_unlock(&cifs_sb->tlink_tree_lock); + goto done; + } + + tmp_list->dentry = cfid->dentry; + cfid->dentry = NULL; + + list_add_tail(&tmp_list->entry, &entry); + } + spin_unlock(&cfids->cfid_list_lock); + } + spin_unlock(&cifs_sb->tlink_tree_lock); + +done: + list_for_each_entry_safe(tmp_list, q, &entry, entry) { + list_del(&tmp_list->entry); + dput(tmp_list->dentry); + kfree(tmp_list); + } + + /* Flush any pending work that will drop dentries */ + flush_workqueue(cfid_put_wq); +} + +/* + * 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; + + if (cfids == NULL) + return; + + /* + * Mark all the cfids as closed, and move them to the cfids->dying list. + * They'll be cleaned up by laundromat. Take a reference to each cfid + * during this process. + */ + spin_lock(&cfids->cfid_list_lock); + list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { + list_move(&cfid->entry, &cfids->dying); + cfids->num_entries--; + cfid->is_open = false; + cfid->on_list = false; + if (cfid->has_lease) { + /* + * The lease was never cancelled from the server, + * so steal that reference. + */ + cfid->has_lease = false; + } else + kref_get(&cfid->refcount); + } + spin_unlock(&cfids->cfid_list_lock); + + /* run laundromat unconditionally now as there might have been previously queued work */ + mod_delayed_work(cfid_put_wq, &cfids->laundromat_work, 0); + flush_delayed_work(&cfids->laundromat_work); +} + +static void +cached_dir_offload_close(struct work_struct *work) +{ + struct cached_fid *cfid = container_of(work, + struct cached_fid, close_work); + struct cifs_tcon *tcon = cfid->tcon; + + WARN_ON(cfid->on_list); + + close_cached_dir(cfid); + cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cached_close); +} + +/* + * Release the cached directory's dentry, and then queue work to drop cached + * directory itself (closing on server if needed). + * + * Must be called with a reference to the cached_fid and a reference to the + * tcon. + */ +static void cached_dir_put_work(struct work_struct *work) +{ + struct cached_fid *cfid = container_of(work, struct cached_fid, + put_work); + dput(cfid->dentry); + cfid->dentry = NULL; + + queue_work(serverclose_wq, &cfid->close_work); +} + +bool 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->has_lease = false; + 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--; + + ++tcon->tc_count; + trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, + netfs_trace_tcon_ref_get_cached_lease_break); + queue_work(cfid_put_wq, &cfid->put_work); + 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->close_work, cached_dir_offload_close); + INIT_WORK(&cfid->put_work, cached_dir_put_work); + INIT_LIST_HEAD(&cfid->entry); + INIT_LIST_HEAD(&cfid->dirents.entries); + mutex_init(&cfid->dirents.de_mutex); + kref_init(&cfid->refcount); + return cfid; +} + +static void free_cached_dir(struct cached_fid *cfid) +{ + struct cached_dirent *dirent, *q; + + WARN_ON(work_pending(&cfid->close_work)); + WARN_ON(work_pending(&cfid->put_work)); + + 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); + } + + /* adjust tcon-level counters and reset per-dir accounting */ + if (cfid->cfids) { + if (cfid->dirents.entries_count) + atomic_long_sub((long)cfid->dirents.entries_count, + &cfid->cfids->total_dirents_entries); + if (cfid->dirents.bytes_used) { + atomic64_sub((long long)cfid->dirents.bytes_used, + &cfid->cfids->total_dirents_bytes); + atomic64_sub((long long)cfid->dirents.bytes_used, + &cifs_dircache_bytes_used); + } + } + cfid->dirents.entries_count = 0; + cfid->dirents.bytes_used = 0; + + kfree(cfid->path); + cfid->path = NULL; + kfree(cfid); +} + +static void cfids_laundromat_worker(struct work_struct *work) +{ + struct cached_fids *cfids; + struct cached_fid *cfid, *q; + LIST_HEAD(entry); + + cfids = container_of(work, struct cached_fids, laundromat_work.work); + + spin_lock(&cfids->cfid_list_lock); + /* move cfids->dying to the local list */ + list_cut_before(&entry, &cfids->dying, &cfids->dying); + + list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { + if (cfid->last_access_time && + time_after(jiffies, cfid->last_access_time + HZ * dir_cache_timeout)) { + cfid->on_list = false; + list_move(&cfid->entry, &entry); + cfids->num_entries--; + if (cfid->has_lease) { + /* + * Our lease has not yet been cancelled from the + * server. Steal that reference. + */ + cfid->has_lease = false; + } else + kref_get(&cfid->refcount); + } + } + spin_unlock(&cfids->cfid_list_lock); + + list_for_each_entry_safe(cfid, q, &entry, entry) { + list_del(&cfid->entry); + + dput(cfid->dentry); + cfid->dentry = NULL; + + if (cfid->is_open) { + spin_lock(&cifs_tcp_ses_lock); + ++cfid->tcon->tc_count; + trace_smb3_tcon_ref(cfid->tcon->debug_id, cfid->tcon->tc_count, + netfs_trace_tcon_ref_get_cached_laundromat); + spin_unlock(&cifs_tcp_ses_lock); + queue_work(serverclose_wq, &cfid->close_work); + } else + /* + * Drop the ref-count from above, either the lease-ref (if there + * was one) or the extra one acquired. + */ + close_cached_dir(cfid); + } + queue_delayed_work(cfid_put_wq, &cfids->laundromat_work, + dir_cache_timeout * HZ); +} + +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); + INIT_LIST_HEAD(&cfids->dying); + + INIT_DELAYED_WORK(&cfids->laundromat_work, cfids_laundromat_worker); + queue_delayed_work(cfid_put_wq, &cfids->laundromat_work, + dir_cache_timeout * HZ); + + atomic_long_set(&cfids->total_dirents_entries, 0); + atomic64_set(&cfids->total_dirents_bytes, 0); + + 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); + + if (cfids == NULL) + return; + + cancel_delayed_work_sync(&cfids->laundromat_work); + + 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); + } + list_for_each_entry_safe(cfid, q, &cfids->dying, 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); +} |