diff options
Diffstat (limited to 'fs/smb/client/cached_dir.c')
-rw-r--r-- | fs/smb/client/cached_dir.c | 99 |
1 files changed, 44 insertions, 55 deletions
diff --git a/fs/smb/client/cached_dir.c b/fs/smb/client/cached_dir.c index 0ff2491c311d..06eb19dabb0e 100644 --- a/fs/smb/client/cached_dir.c +++ b/fs/smb/client/cached_dir.c @@ -59,6 +59,16 @@ static struct cached_fid *find_or_create_cached_dir(struct cached_fids *cfids, 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; + spin_unlock(&cfids->cfid_list_lock); return cfid; } @@ -176,12 +186,12 @@ replay_again: return -ENOENT; } /* - * Return cached fid if it has a lease. Otherwise, it is either a new - * entry or laundromat worker removed it from @cfids->entries. Caller - * will put last reference if the latter. + * 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. */ spin_lock(&cfids->cfid_list_lock); - if (cfid->has_lease) { + if (cfid->has_lease && cfid->time) { spin_unlock(&cfids->cfid_list_lock); *ret_cfid = cfid; kfree(utf16_path); @@ -267,15 +277,6 @@ replay_again: smb2_set_related(&rqst[1]); - /* - * Set @cfid->has_lease to true before sending out compounded request so - * its 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. Concurrent processes won't be to use it yet - * due to @cfid->time being zero. - */ - cfid->has_lease = true; - if (retries) { smb2_set_replay(server, &rqst[0]); smb2_set_replay(server, &rqst[1]); @@ -347,6 +348,7 @@ oshr_free: 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) { @@ -358,23 +360,14 @@ oshr_free: /* * We are guaranteed to have two references at this * point. One for the caller and one for a potential - * lease. Release the Lease-ref so that the directory - * will be closed when the caller closes the cached - * handle. + * lease. Release one here, and the second below. */ cfid->has_lease = false; - spin_unlock(&cfids->cfid_list_lock); kref_put(&cfid->refcount, smb2_close_cached_fid); - goto out; } spin_unlock(&cfids->cfid_list_lock); - } -out: - if (rc) { - if (cfid->is_open) - SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid, - cfid->fid.volatile_fid); - free_cached_dir(cfid); + + kref_put(&cfid->refcount, smb2_close_cached_fid); } else { *ret_cfid = cfid; atomic_inc(&tcon->num_remote_opens); @@ -401,7 +394,7 @@ int open_cached_dir_by_dentry(struct cifs_tcon *tcon, 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"); + cifs_dbg(FYI, "found a cached file handle by dentry\n"); kref_get(&cfid->refcount); *ret_cfid = cfid; spin_unlock(&cfids->cfid_list_lock); @@ -512,25 +505,24 @@ void invalidate_all_cached_dirs(struct cifs_tcon *tcon) cfids->num_entries--; cfid->is_open = false; cfid->on_list = false; - /* To prevent race with smb2_cached_lease_break() */ - kref_get(&cfid->refcount); + 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); 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*/ + /* + * Drop the ref-count from above, either the lease-ref (if there + * was one) or the extra one acquired. + */ kref_put(&cfid->refcount, smb2_close_cached_fid); } } @@ -541,9 +533,6 @@ 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); } @@ -561,6 +550,7 @@ int cached_dir_lease_break(struct cifs_tcon *tcon, __u8 lease_key[16]) !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 @@ -638,8 +628,14 @@ static void cfids_laundromat_worker(struct work_struct *work) cfid->on_list = false; list_move(&cfid->entry, &entry); cfids->num_entries--; - /* To prevent race with smb2_cached_lease_break() */ - kref_get(&cfid->refcount); + 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); @@ -651,17 +647,10 @@ static void cfids_laundromat_worker(struct work_struct *work) * with it. */ cancel_work_sync(&cfid->lease_break); - if (cfid->has_lease) { - /* - * Our lease has not yet been 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 */ + /* + * Drop the ref-count from above, either the lease-ref (if there + * was one) or the extra one acquired. + */ kref_put(&cfid->refcount, smb2_close_cached_fid); } queue_delayed_work(cifsiod_wq, &cfids->laundromat_work, |