From patchwork Thu Nov 9 15:39:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13451225 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 7A9F020332 for ; Thu, 9 Nov 2023 15:40:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="iApU+8g2" Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07983358C for ; Thu, 9 Nov 2023 07:40:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1699544434; 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=EsdaavxzQFrCmF0h4nEsVxw66N+/bYbfxItJ2VZRPVw=; b=iApU+8g2mZ5+94iYorfZhytrmBljaGC3waegzgX7VsF0ZbdmsH2OjqOCw1iPH45XbTGzFS jUl6wFBYwqL1xWKtyqN+BGUL5E09FMuKLXcsl6WebmLahanYb0w6CL3Q64snTVZxuHD3nf N+RsDt26pr78UUZIQxNiKwOTvjAc0f0= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-32-SI2N2WcWOviWEg6U-p1gFw-1; Thu, 09 Nov 2023 10:40:27 -0500 X-MC-Unique: SI2N2WcWOviWEg6U-p1gFw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C53342810D52; Thu, 9 Nov 2023 15:40:22 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.42.28.13]) by smtp.corp.redhat.com (Postfix) with ESMTP id E15CF1C060AE; Thu, 9 Nov 2023 15:40:21 +0000 (UTC) From: David Howells To: Marc Dionne Cc: David Howells , linux-afs@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Jeffrey E Altman Subject: [PATCH 08/41] afs: Add comments on abort handling Date: Thu, 9 Nov 2023 15:39:31 +0000 Message-ID: <20231109154004.3317227-9-dhowells@redhat.com> In-Reply-To: <20231109154004.3317227-1-dhowells@redhat.com> References: <20231109154004.3317227-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 Add some comments on AFS abort code handling in the rotation algorithm and adjust the errors produced to match. Reported-by: Jeffrey E Altman Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org Reviewed-by: Jeffrey Altman --- fs/afs/rotate.c | 100 ++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 89 insertions(+), 11 deletions(-) diff --git a/fs/afs/rotate.c b/fs/afs/rotate.c index a840c3588ebb..180bcad081dd 100644 --- a/fs/afs/rotate.c +++ b/fs/afs/rotate.c @@ -13,6 +13,7 @@ #include #include "internal.h" #include "afs_fs.h" +#include "protocol_uae.h" /* * Begin iteration through a server list, starting with the vnode's last used @@ -143,6 +144,11 @@ bool afs_select_fileserver(struct afs_operation *op) case -ECONNABORTED: /* The far side rejected the operation on some grounds. This * might involve the server being busy or the volume having been moved. + * + * Note that various V* errors should not be sent to a cache manager + * by a fileserver as they should be translated to more modern UAE* + * errors instead. IBM AFS and OpenAFS fileservers, however, do leak + * these abort codes. */ switch (op->ac.abort_code) { case VNOVOL: @@ -150,6 +156,11 @@ bool afs_select_fileserver(struct afs_operation *op) * - May indicate that the VL is wrong - retry once and compare * the results. * - May indicate that the fileserver couldn't attach to the vol. + * - The volume might have been temporarily removed so that it can + * be replaced by a volume restore. "vos" might have ended one + * transaction and has yet to create the next. + * - The volume might not be blessed or might not be in-service + * (administrative action). */ if (op->flags & AFS_OPERATION_VNOVOL) { op->error = -EREMOTEIO; @@ -183,16 +194,56 @@ bool afs_select_fileserver(struct afs_operation *op) _leave(" = t [vnovol]"); return true; - case VSALVAGE: /* TODO: Should this return an error or iterate? */ case VVOLEXISTS: - case VNOSERVICE: case VONLINE: - case VDISKFULL: - case VOVERQUOTA: - op->error = afs_abort_to_error(op->ac.abort_code); + /* These should not be returned from the fileserver. */ + pr_warn("Fileserver returned unexpected abort %d\n", + op->ac.abort_code); + op->error = -EREMOTEIO; + goto next_server; + + case VNOSERVICE: + /* Prior to AFS 3.2 VNOSERVICE was returned from the fileserver + * if the volume was neither in-service nor administratively + * blessed. All usage was replaced by VNOVOL because AFS 3.1 and + * earlier cache managers did not handle VNOSERVICE and assumed + * it was the client OSes errno 105. + * + * Starting with OpenAFS 1.4.8 VNOSERVICE was repurposed as the + * fileserver idle dead time error which was sent in place of + * RX_CALL_TIMEOUT (-3). The error was intended to be sent if the + * fileserver took too long to send a reply to the client. + * RX_CALL_TIMEOUT would have caused the cache manager to mark the + * server down whereas VNOSERVICE since AFS 3.2 would cause cache + * manager to temporarily (up to 15 minutes) mark the volume + * instance as unusable. + * + * The idle dead logic resulted in cache inconsistency since a + * state changing call that the cache manager assumed was dead + * could still be processed to completion by the fileserver. This + * logic was removed in OpenAFS 1.8.0 and VNOSERVICE is no longer + * returned. However, many 1.4.8 through 1.6.24 fileservers are + * still in existence. + * + * AuriStorFS fileservers have never returned VNOSERVICE. + * + * VNOSERVICE should be treated as an alias for RX_CALL_TIMEOUT.. + */ + case RX_CALL_TIMEOUT: + op->error = -ETIMEDOUT; goto next_server; + case VSALVAGING: /* This error should not be leaked to cache managers + * but is from OpenAFS demand attach fileservers. + * It should be treated as an alias for VOFFLINE. + */ + case VSALVAGE: /* VSALVAGE should be treated as a synonym of VOFFLINE */ case VOFFLINE: + /* The volume is in use by the volserver or another volume utility + * for an operation that might alter the contents. The volume is + * expected to come back but it might take a long time (could be + * days). + */ if (!test_and_set_bit(AFS_VOLUME_OFFLINE, &op->volume->flags)) { afs_busy(op->volume, op->ac.abort_code); clear_bit(AFS_VOLUME_BUSY, &op->volume->flags); @@ -207,11 +258,19 @@ bool afs_select_fileserver(struct afs_operation *op) } goto busy; - case VSALVAGING: - case VRESTARTING: + case VRESTARTING: /* The fileserver is either shutting down or starting up. */ case VBUSY: - /* Retry after going round all the servers unless we - * have a file lock we need to maintain. + /* The volume is in use by the volserver or another volume utility + * for an operation that is not expected to alter the contents of + * the volume. VBUSY should not be returned for a ROVOL or + * BACKVOL (but many OpenAFS fileserver versions are broken). The + * fileserver is supposed to continue serving content from ROVOLs + * and BACKVOLs during an ITBusy transaction because the content + * cannot change. The volume is expected to come back but it + * might take awhile. + * + * Retry after going round all the servers unless we have a file + * lock we need to maintain. */ if (op->flags & AFS_OPERATION_NO_VSLEEP) { op->error = -EBUSY; @@ -226,7 +285,7 @@ bool afs_select_fileserver(struct afs_operation *op) if (!afs_sleep_and_retry(op)) goto failed; - /* Retry with same server & address */ + /* Retry with same server & address */ _leave(" = t [vbusy]"); return true; } @@ -270,10 +329,29 @@ bool afs_select_fileserver(struct afs_operation *op) goto restart_from_beginning; + case VDISKFULL: + case UAENOSPC: + /* The partition is full. Only applies to RWVOLs. + * Translate locally and return ENOSPC. + * No replicas to failover to. + */ + op->error = -ENOSPC; + goto failed_but_online; + + case VOVERQUOTA: + case UAEDQUOT: + /* Volume is full. Only applies to RWVOLs. + * Translate locally and return EDQUOT. + * No replicas to failover to. + */ + op->error = -EDQUOT; + goto failed_but_online; + default: + op->error = afs_abort_to_error(op->ac.abort_code); + failed_but_online: clear_bit(AFS_VOLUME_OFFLINE, &op->volume->flags); clear_bit(AFS_VOLUME_BUSY, &op->volume->flags); - op->error = afs_abort_to_error(op->ac.abort_code); goto failed; }