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This happens in two cases: 1. when a new cinode is allocated 2. when an oplock break is being processed This code change allows these code paths to use a ref on the dentry (and hence the inode). That way, umount is ensured to clean up SMB client resources when it's the last ref on the superblock (For ex: when same objects are shared). The code change also moves the call to close all the files in deferred close list to the umount code path. Signed-off-by: Shyam Prasad N --- fs/smb/client/cifsfs.c | 4 ++-- fs/smb/client/cifsproto.h | 2 ++ fs/smb/client/connect.c | 2 ++ fs/smb/client/file.c | 11 ----------- fs/smb/client/misc.c | 36 ++++++++++++++++++++++++++++++++++++ 5 files changed, 42 insertions(+), 13 deletions(-) diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c index a3dc7cb1ab541..277dabd982cbd 100644 --- a/fs/smb/client/cifsfs.c +++ b/fs/smb/client/cifsfs.c @@ -331,10 +331,11 @@ static void cifs_kill_sb(struct super_block *sb) /* * We need to release all dentries for the cached directories - * before we kill the sb. + * and close all deferred file handles before we kill the sb. */ if (cifs_sb->root) { close_all_cached_dirs(cifs_sb); + cifs_close_all_deferred_files_sb(cifs_sb); /* finally release root dentry */ dput(cifs_sb->root); @@ -865,7 +866,6 @@ static void cifs_umount_begin(struct super_block *sb) spin_unlock(&tcon->tc_lock); spin_unlock(&cifs_tcp_ses_lock); - cifs_close_all_deferred_files(tcon); /* cancel_brl_requests(tcon); */ /* BB mark all brl mids as exiting */ /* cancel_notify_requests(tcon); */ if (tcon->ses && tcon->ses->server) { diff --git a/fs/smb/client/cifsproto.h b/fs/smb/client/cifsproto.h index f8c0615d4ee42..5feaeac16b0c5 100644 --- a/fs/smb/client/cifsproto.h +++ b/fs/smb/client/cifsproto.h @@ -302,6 +302,8 @@ extern void cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode); extern void cifs_close_all_deferred_files(struct cifs_tcon *cifs_tcon); +extern void cifs_close_all_deferred_files_sb(struct cifs_sb_info *cifs_sb); + void cifs_close_deferred_file_under_dentry(struct cifs_tcon *cifs_tcon, struct dentry *dentry); diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c index ce620503e9f70..31745ef692390 100644 --- a/fs/smb/client/connect.c +++ b/fs/smb/client/connect.c @@ -4149,6 +4149,7 @@ cifs_umount(struct cifs_sb_info *cifs_sb) if (cifs_sb->master_tlink) { tcon = cifs_sb->master_tlink->tl_tcon; if (tcon) { + cifs_close_all_deferred_files(tcon); spin_lock(&tcon->sb_list_lock); list_del_init(&cifs_sb->tcon_sb_link); spin_unlock(&tcon->sb_list_lock); @@ -4163,6 +4164,7 @@ cifs_umount(struct cifs_sb_info *cifs_sb) rb_erase(node, root); spin_unlock(&cifs_sb->tlink_tree_lock); + cifs_close_all_deferred_files(tlink->tl_tcon); cifs_put_tlink(tlink); spin_lock(&cifs_sb->tlink_tree_lock); } diff --git a/fs/smb/client/file.c b/fs/smb/client/file.c index 7ff5cc9c5c5b7..0b80b11a9864d 100644 --- a/fs/smb/client/file.c +++ b/fs/smb/client/file.c @@ -712,8 +712,6 @@ struct cifsFileInfo *cifs_new_fileinfo(struct cifs_fid *fid, struct file *file, mutex_init(&cfile->fh_mutex); spin_lock_init(&cfile->file_info_lock); - cifs_sb_active(inode->i_sb); - /* * If the server returned a read oplock and we have mandatory brlocks, * set oplock level to None. @@ -768,7 +766,6 @@ static void cifsFileInfo_put_final(struct cifsFileInfo *cifs_file) struct inode *inode = d_inode(cifs_file->dentry); struct cifsInodeInfo *cifsi = CIFS_I(inode); struct cifsLockInfo *li, *tmp; - struct super_block *sb = inode->i_sb; /* * Delete any outstanding lock records. We'll lose them when the file @@ -786,7 +783,6 @@ static void cifsFileInfo_put_final(struct cifsFileInfo *cifs_file) cifs_put_tlink(cifs_file->tlink); dput(cifs_file->dentry); - cifs_sb_deactive(sb); kfree(cifs_file->symlink_target); kfree(cifs_file); } @@ -3163,12 +3159,6 @@ void cifs_oplock_break(struct work_struct *work) __u64 persistent_fid, volatile_fid; __u16 net_fid; - /* - * Hold a reference to the superblock to prevent it and its inodes from - * being freed while we are accessing cinode. Otherwise, _cifsFileInfo_put() - * may release the last reference to the sb and trigger inode eviction. - */ - cifs_sb_active(sb); wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS, TASK_UNINTERRUPTIBLE); @@ -3241,7 +3231,6 @@ void cifs_oplock_break(struct work_struct *work) cifs_put_tlink(tlink); out: cifs_done_oplock_break(cinode); - cifs_sb_deactive(sb); } static int cifs_swap_activate(struct swap_info_struct *sis, diff --git a/fs/smb/client/misc.c b/fs/smb/client/misc.c index 9529fa385938e..dfeb1faff8568 100644 --- a/fs/smb/client/misc.c +++ b/fs/smb/client/misc.c @@ -28,6 +28,11 @@ #include "fs_context.h" #include "cached_dir.h" +struct tcon_list { + struct list_head entry; + struct cifs_tcon *tcon; +}; + /* The xid serves as a useful identifier for each incoming vfs request, in a similar way to the mid which is useful to track each sent smb, and CurrentXid can also provide a running counter (although it @@ -171,6 +176,7 @@ tconInfoFree(struct cifs_tcon *tcon, enum smb3_tcon_ref_trace trace) } trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, trace); free_cached_dirs(tcon->cfids); + atomic_dec(&tconInfoAllocCount); kfree(tcon->nativeFileSystem); kfree_sensitive(tcon->password); @@ -840,6 +846,36 @@ cifs_close_all_deferred_files(struct cifs_tcon *tcon) } } +void cifs_close_all_deferred_files_sb(struct cifs_sb_info *cifs_sb) +{ + struct rb_root *root = &cifs_sb->tlink_tree; + struct rb_node *node; + struct cifs_tcon *tcon; + struct tcon_link *tlink; + struct tcon_list *tmp_list, *q; + LIST_HEAD(tcon_head); + + 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; + tmp_list = kmalloc(sizeof(*tmp_list), GFP_ATOMIC); + if (tmp_list == NULL) + break; + tmp_list->tcon = tcon; + list_add_tail(&tmp_list->entry, &tcon_head); + } + spin_unlock(&cifs_sb->tlink_tree_lock); + + list_for_each_entry_safe(tmp_list, q, &tcon_head, entry) { + cifs_close_all_deferred_files(tmp_list->tcon); + list_del(&tmp_list->entry); + kfree(tmp_list); + } +} + void cifs_close_deferred_file_under_dentry(struct cifs_tcon *tcon, struct dentry *dentry) { -- 2.43.0