From patchwork Mon Mar 31 13:33:13 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Zhaolong X-Patchwork-Id: 14033618 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4E55A1DFE0A; Mon, 31 Mar 2025 13:39:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.255 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743428364; cv=none; b=BoPZ3TqGnP0IPEYgGfYQAO0EVD3oXetXW1fn0puHAgZmCNxV1T6UkbOW3iAQCV83todHYIN3ax1VZrZ4sA7TO4vJTInyuzssZ66e/zjqW1FHKmifwxuEJskAH7CzJVGpThRhkhLxqYT/mygXf6XCvOWepWexWSyqBmNh+2++Tm8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743428364; c=relaxed/simple; bh=dOx95MuekbEMi2IU+RmUOmcI3GSosGWmUni5Knb+IqQ=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=BUFv2ft3lcb5Twc+D7NVfFPW4A2RYb4DhM4ZAOhqY6DbLxnhCvRpZserxH9WUKpChUnXXyiWLMzzagjQ+PGR8TWrUsVsArtWbrR0/UfJc7HdPrcObdVs5lPwu9FvE0edfn4R6LQ0U6Blcyo6M2j0xFTWVIPt00U0iagXajZyIno= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.255 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.105]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4ZRBzs4LrNz1d14d; Mon, 31 Mar 2025 21:38:49 +0800 (CST) Received: from kwepemg500010.china.huawei.com (unknown [7.202.181.71]) by mail.maildlp.com (Postfix) with ESMTPS id DAB1B1400DC; Mon, 31 Mar 2025 21:39:18 +0800 (CST) Received: from huawei.com (10.175.104.67) by kwepemg500010.china.huawei.com (7.202.181.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 31 Mar 2025 21:39:17 +0800 From: Wang Zhaolong To: , CC: , , , , , , Subject: [PATCH next 1/3] smb:client: smb: client: Add reverse mapping from tcon to superblocks Date: Mon, 31 Mar 2025 21:33:13 +0800 Message-ID: <20250331133315.117666-2-wangzhaolong1@huawei.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250331133315.117666-1-wangzhaolong1@huawei.com> References: <20250331133315.117666-1-wangzhaolong1@huawei.com> Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemg500010.china.huawei.com (7.202.181.71) Currently, when a SMB connection is reset and renegotiated with the server, there's no way to update all related mount points with new negotiated sizes. This is because while superblocks (cifs_sb_info) maintain references to tree connections (tcon) through tcon_link structures, there is no reverse mapping from a tcon back to all the superblocks using it. This patch adds a bidirectional relationship between tcon and cifs_sb_info structures by: 1. Adding a cifs_sb_list to tcon structure with appropriate locking 2. Adding tcon_sb_link to cifs_sb_info to join the list 3. Managing the list entries during mount and umount operations The bidirectional relationship enables future functionality to locate and update all superblocks connected to a specific tree connection, such as: - Updating negotiated parameters after reconnection - Efficiently notifying all affected mounts of capability changes This is the first part of a series to improve connection resilience by keeping all mount parameters in sync with server capabilities after reconnection. Signed-off-by: Wang Zhaolong --- fs/smb/client/cifs_fs_sb.h | 1 + fs/smb/client/cifsglob.h | 3 ++- fs/smb/client/connect.c | 15 +++++++++++++++ fs/smb/client/misc.c | 2 ++ 4 files changed, 20 insertions(+), 1 deletion(-) diff --git a/fs/smb/client/cifs_fs_sb.h b/fs/smb/client/cifs_fs_sb.h index 651759192280..5e8d163cb5f8 100644 --- a/fs/smb/client/cifs_fs_sb.h +++ b/fs/smb/client/cifs_fs_sb.h @@ -47,10 +47,11 @@ #define CIFS_MOUNT_RW_CACHE 0x40000000 /* assumes only client accessing */ #define CIFS_MOUNT_SHUTDOWN 0x80000000 struct cifs_sb_info { struct rb_root tlink_tree; + struct list_head tcon_sb_link; spinlock_t tlink_tree_lock; struct tcon_link *master_tlink; struct nls_table *local_nls; struct smb3_fs_context *ctx; atomic_t active; diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h index cddeb2adbf4a..be1760ceca6c 100644 --- a/fs/smb/client/cifsglob.h +++ b/fs/smb/client/cifsglob.h @@ -1317,11 +1317,12 @@ struct cifs_tcon { struct fscache_volume *fscache; /* cookie for share */ struct mutex fscache_lock; /* Prevent regetting a cookie */ #endif struct list_head pending_opens; /* list of incomplete opens */ struct cached_fids *cfids; - /* BB add field for back pointer to sb struct(s)? */ + struct list_head cifs_sb_list; + spinlock_t sb_list_lock; #ifdef CONFIG_CIFS_DFS_UPCALL struct delayed_work dfs_cache_work; struct list_head dfs_ses_list; #endif struct delayed_work query_interfaces; /* query interfaces workqueue job */ diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c index 73f93a35eedd..409b4e0dac26 100644 --- a/fs/smb/client/connect.c +++ b/fs/smb/client/connect.c @@ -3336,10 +3336,11 @@ void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon, int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb) { struct smb3_fs_context *ctx = cifs_sb->ctx; INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks); + INIT_LIST_HEAD(&cifs_sb->tcon_sb_link); spin_lock_init(&cifs_sb->tlink_tree_lock); cifs_sb->tlink_tree = RB_ROOT; cifs_dbg(FYI, "file mode: %04ho dir mode: %04ho\n", @@ -3568,10 +3569,14 @@ static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses, cifs_sb->master_tlink = tlink; spin_lock(&cifs_sb->tlink_tree_lock); tlink_rb_insert(&cifs_sb->tlink_tree, tlink); spin_unlock(&cifs_sb->tlink_tree_lock); + spin_lock(&tcon->sb_list_lock); + list_add(&cifs_sb->tcon_sb_link, &tcon->cifs_sb_list); + spin_unlock(&tcon->sb_list_lock); + queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks, TLINK_IDLE_EXPIRE); return 0; } @@ -3909,13 +3914,23 @@ void cifs_umount(struct cifs_sb_info *cifs_sb) { struct rb_root *root = &cifs_sb->tlink_tree; struct rb_node *node; struct tcon_link *tlink; + struct cifs_tcon *tcon = NULL; cancel_delayed_work_sync(&cifs_sb->prune_tlinks); + if (cifs_sb->master_tlink) { + tcon = cifs_sb->master_tlink->tl_tcon; + if (tcon) { + spin_lock(&tcon->sb_list_lock); + list_del_init(&cifs_sb->tcon_sb_link); + spin_unlock(&tcon->sb_list_lock); + } + } + spin_lock(&cifs_sb->tlink_tree_lock); while ((node = rb_first(root))) { tlink = rb_entry(node, struct tcon_link, tl_rbnode); cifs_get_tlink(tlink); clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags); diff --git a/fs/smb/client/misc.c b/fs/smb/client/misc.c index b328dc5c7988..7b6ed9b23e71 100644 --- a/fs/smb/client/misc.c +++ b/fs/smb/client/misc.c @@ -135,12 +135,14 @@ tcon_info_alloc(bool dir_leases_enabled, enum smb3_tcon_ref_trace trace) ret_buf->debug_id = atomic_inc_return(&tcon_debug_id); ret_buf->tc_count = 1; spin_lock_init(&ret_buf->tc_lock); INIT_LIST_HEAD(&ret_buf->openFileList); INIT_LIST_HEAD(&ret_buf->tcon_list); + INIT_LIST_HEAD(&ret_buf->cifs_sb_list); spin_lock_init(&ret_buf->open_file_lock); spin_lock_init(&ret_buf->stat_lock); + spin_lock_init(&ret_buf->sb_list_lock); atomic_set(&ret_buf->num_local_opens, 0); atomic_set(&ret_buf->num_remote_opens, 0); ret_buf->stats_from_time = ktime_get_real_seconds(); #ifdef CONFIG_CIFS_FSCACHE mutex_init(&ret_buf->fscache_lock);