From patchwork Tue Apr 2 01:44:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paulo Alcantara X-Patchwork-Id: 13613228 Received: from mx.manguebit.com (mx.manguebit.com [167.235.159.17]) (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 7B6E5C8C7 for ; Tue, 2 Apr 2024 01:44:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=167.235.159.17 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712022277; cv=pass; b=sFcWhTZtB/SO5bwBOY/L7pvvnb8k69FN5gdJdj6m/9P2yMeD1IPAByZzTfpMRIcABmWKfewoxFrfoP2FDUFqj5R3UYxgOp+J22O5OhZKqD/ovtdLfYY7CLYQsVc056IUX8/7U60v20xGPrhvoF3zBU7eAZiixAnCXWeCCZRhTtI= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712022277; c=relaxed/simple; bh=QkPuBshoXjA0KjitqAnAIsdnd4VyNFUOEmnUrBsGHeI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dB2gKIvFbNhPRp4b1z0J3upOzrMVBCxxYgBiCNYDT3aTeo4y+ju9QOpjIj+I3EtvKkBvYgn7Krfw2di1A1U25YwdCDEXlsgObGf40JJb3ky6bCW8EKQlua+PMETt+HQXyLXW+X5m8trLc6jc/gNbL7GyUnI60HGxW8PTu+xre8o= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=manguebit.com; spf=pass smtp.mailfrom=manguebit.com; dkim=pass (2048-bit key) header.d=manguebit.com header.i=@manguebit.com header.b=k+JRX36c; arc=pass smtp.client-ip=167.235.159.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=manguebit.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=manguebit.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=manguebit.com header.i=@manguebit.com header.b="k+JRX36c" From: Paulo Alcantara DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=manguebit.com; s=dkim; t=1712022272; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RPzfgaYhNq4/iJMnxLD+3a0KEoGBLXpCMiuKPVZW44k=; b=k+JRX36ciJCIFdH3lhxJ3LxDa93ALTpsl1IeGWOpPDdF+irk/uUWdjRYcMJIL7AyJI/7CX gOlaUKLe1Ei2VfWATVzMb+5H/KUZy2zPHsbBO5K/DaRwlKtiLRqnOcEfm0x157p3ksX4YK h8Asgs7/e+hl4DHZV81dACYRw6fmcEDmUAQuKOvuHaYdj4T2FsRq3NUNAVQWbm5et56mWN mgm+ToJ2JlNe2C7xRYznF3v+JaeZfQlXcfIg4IGziwjuIrTmJRrxMK7EMN/6UhmleN6AVC fpsFbLqvX1rBAnrp5zO1i4JTgg+yrRCmDQhdVtCAAnXNDaUGebJ6FXBiKQR99g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=manguebit.com; s=dkim; t=1712022272; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RPzfgaYhNq4/iJMnxLD+3a0KEoGBLXpCMiuKPVZW44k=; b=UTuf94pAkMkmPyfFrKpW3GId6UOhHfuyjDnpnqBqWj19kTlD9KwI1VorgTy+Ewxfsj/sMi OgN7wFxzyTAdQVF9te2YXp7/+rQ/zJttXRPu1QBukv8yRhcIuX6AGxJRhxbM9qn6rJf2f6 uri60U/7Xu8M7HJpvstyMy10iPiG8b95pESzvw0CcaKAnYzCdb/ZDX4aka+wyUqkyG3NR1 Iv/CWUWIHoeWLYy+yGFLTEF41gnsrUmaGO3tlVloVQdAgHRdg/U2hEfCHOJkynSHS2xCNW KTTsUFxlCAvajw/8dx0rx4GD9qO5NRqLI4TDXLyLbq0w0VFVy7bGaahHJC6/Lg== ARC-Authentication-Results: i=1; ORIGINATING; auth=pass smtp.mailfrom=pc@manguebit.com ARC-Seal: i=1; s=dkim; d=manguebit.com; t=1712022272; a=rsa-sha256; cv=none; b=htNQeeHJys0wUA4kRqLA0iviAuYRS/vG7sK/H35q7dqsPZy9j4Z5WGGbOQa9gyzJiktcUd 6SWE9iS71+Qe/P1fyHPApBKkbepCDq203kOWhspUbnVc6cTx/CpPaSd6XxOPMLwh4xwxHJ evAdlZibdrYaThNLyKVaAABpWqomlI5lG161vvbb/Ksh+BF+5D8Eqgz0jA1ALuK0p5vHC1 kyjJBjUGwbKNgq94M4aMzmN0C0NIJmxL8Rx2eWRkZvvTT7LeeHW0z1p2O78RRnbDgeeiam AqyQH/jDleCo9dGrLUqBf0gr47w434iLMATan8e40DmGMHH6+HmjwuxWnlqLMA== To: smfrench@gmail.com Cc: linux-cifs@vger.kernel.org, Paulo Alcantara Subject: [PATCH 2/4] smb: client: refresh referral without acquiring refpath_lock Date: Mon, 1 Apr 2024 22:44:07 -0300 Message-ID: <20240402014409.145562-2-pc@manguebit.com> In-Reply-To: <20240402014409.145562-1-pc@manguebit.com> References: <20240402014409.145562-1-pc@manguebit.com> Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Avoid refreshing DFS referral with refpath_lock acquired as the I/O could block for a while due to a potentially disconnected or slow DFS root server and then making other threads - that use same @server and don't require a DFS root server - unable to make any progress. Signed-off-by: Paulo Alcantara (Red Hat) --- fs/smb/client/dfs_cache.c | 44 +++++++++++++++++++++------------------ 1 file changed, 24 insertions(+), 20 deletions(-) diff --git a/fs/smb/client/dfs_cache.c b/fs/smb/client/dfs_cache.c index 0552a864ff08..11c8efecf7aa 100644 --- a/fs/smb/client/dfs_cache.c +++ b/fs/smb/client/dfs_cache.c @@ -1172,8 +1172,8 @@ static bool is_ses_good(struct cifs_ses *ses) return ret; } -/* Refresh dfs referral of tcon and mark it for reconnect if needed */ -static int __refresh_tcon(const char *path, struct cifs_ses *ses, bool force_refresh) +/* Refresh dfs referral of @ses and mark it for reconnect if needed */ +static void __refresh_ses_referral(struct cifs_ses *ses, bool force_refresh) { struct TCP_Server_Info *server = ses->server; DFS_CACHE_TGT_LIST(old_tl); @@ -1181,10 +1181,21 @@ static int __refresh_tcon(const char *path, struct cifs_ses *ses, bool force_ref bool needs_refresh = false; struct cache_entry *ce; unsigned int xid; + char *path = NULL; int rc = 0; xid = get_xid(); + mutex_lock(&server->refpath_lock); + if (server->leaf_fullpath) { + path = kstrdup(server->leaf_fullpath + 1, GFP_ATOMIC); + if (!path) + rc = -ENOMEM; + } + mutex_unlock(&server->refpath_lock); + if (!path) + goto out; + down_read(&htable_rw_lock); ce = lookup_cache_entry(path); needs_refresh = force_refresh || IS_ERR(ce) || cache_entry_expired(ce); @@ -1218,19 +1229,17 @@ static int __refresh_tcon(const char *path, struct cifs_ses *ses, bool force_ref free_xid(xid); dfs_cache_free_tgts(&old_tl); dfs_cache_free_tgts(&new_tl); - return rc; + kfree(path); } -static int refresh_tcon(struct cifs_tcon *tcon, bool force_refresh) +static inline void refresh_ses_referral(struct cifs_ses *ses) { - struct TCP_Server_Info *server = tcon->ses->server; - struct cifs_ses *ses = tcon->ses; + __refresh_ses_referral(ses, false); +} - mutex_lock(&server->refpath_lock); - if (server->leaf_fullpath) - __refresh_tcon(server->leaf_fullpath + 1, ses, force_refresh); - mutex_unlock(&server->refpath_lock); - return 0; +static inline void force_refresh_ses_referral(struct cifs_ses *ses) +{ + __refresh_ses_referral(ses, true); } /** @@ -1271,25 +1280,20 @@ int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb) */ cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; - return refresh_tcon(tcon, true); + force_refresh_ses_referral(tcon->ses); + return 0; } /* Refresh all DFS referrals related to DFS tcon */ void dfs_cache_refresh(struct work_struct *work) { - struct TCP_Server_Info *server; struct cifs_tcon *tcon; struct cifs_ses *ses; tcon = container_of(work, struct cifs_tcon, dfs_cache_work.work); - for (ses = tcon->ses; ses; ses = ses->dfs_root_ses) { - server = ses->server; - mutex_lock(&server->refpath_lock); - if (server->leaf_fullpath) - __refresh_tcon(server->leaf_fullpath + 1, ses, false); - mutex_unlock(&server->refpath_lock); - } + for (ses = tcon->ses; ses; ses = ses->dfs_root_ses) + refresh_ses_referral(ses); queue_delayed_work(dfscache_wq, &tcon->dfs_cache_work, atomic_read(&dfs_cache_ttl) * HZ);