From patchwork Fri Jan 18 17:30:36 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Beno=C3=AEt_Canet?= X-Patchwork-Id: 213703 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 24A762C0079 for ; Sat, 19 Jan 2013 05:00:29 +1100 (EST) Received: from localhost ([::1]:36208 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TwFmy-0007t5-Cf for incoming@patchwork.ozlabs.org; Fri, 18 Jan 2013 12:31:36 -0500 Received: from eggs.gnu.org ([208.118.235.92]:46404) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TwFmE-0005rU-AZ for qemu-devel@nongnu.org; Fri, 18 Jan 2013 12:30:53 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TwFm4-00055Q-SJ for qemu-devel@nongnu.org; Fri, 18 Jan 2013 12:30:50 -0500 Received: from nodalink.pck.nerim.net ([62.212.105.220]:44627 helo=paradis.irqsave.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TwFm4-00055G-F9 for qemu-devel@nongnu.org; Fri, 18 Jan 2013 12:30:40 -0500 Received: by paradis.irqsave.net (Postfix, from userid 1002) id 74FFE874309; Fri, 18 Jan 2013 19:03:03 +0100 (CET) Received: from localhost.localdomain (unknown [192.168.77.1]) by paradis.irqsave.net (Postfix) with ESMTP id 64593874306; Fri, 18 Jan 2013 19:02:35 +0100 (CET) From: =?UTF-8?q?Beno=C3=AEt=20Canet?= To: qemu-devel@nongnu.org Date: Fri, 18 Jan 2013 18:30:36 +0100 Message-Id: <1358530244-9028-4-git-send-email-benoit@irqsave.net> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1358530244-9028-1-git-send-email-benoit@irqsave.net> References: <1358530244-9028-1-git-send-email-benoit@irqsave.net> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 62.212.105.220 Cc: kwolf@redhat.com, pbonzini@redhat.com, =?UTF-8?q?Beno=C3=AEt=20Canet?= , stefanha@redhat.com Subject: [Qemu-devel] [RFC V7 03/11] quorum: Add quorum_open() and quorum_close(). X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Valid quorum resources look like quorum:threshold/total:path/to/image_1: ... :path/to/image_total ':' is used as a separator '\' is the escaping character for filename containing ':' '\' escape itself ',' must be escaped with ',' On the command line for quorum files "img:test.raw", "img2,raw" and "img3.raw" invocation look like: -drive file=quorum:2/3:img\\:test.raw:img2,,raw:img3.raw (note the double \\ and the double ,,) Signed-off-by: Benoit Canet Reviewed-by: Eric Blake --- block/quorum.c | 155 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) diff --git a/block/quorum.c b/block/quorum.c index 0524b63..e157eb1 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -52,11 +52,166 @@ struct QuorumAIOCB { int vote_ret; }; +static int quorum_parse_uint_step_next(const char *start, + const char *name, + const char separator, + unsigned long long *value, + char **next) +{ + int ret; + if (start[0] == '\0') { + qerror_report(QERR_MISSING_PARAMETER, name); + return -EINVAL; + } + ret = parse_uint(start, value, next, 10); + if (ret < 0) { + qerror_report(QERR_INVALID_PARAMETER_TYPE, name, "int"); + return ret; + } + if (**next != separator) { + qerror_report(ERROR_CLASS_GENERIC_ERROR, + "%c separator required after %s", + separator, name); + return -EINVAL; + } + *next += 1; + return 0; +} + +/* Valid quorum resources look like + * quorum:threshold/total:path/to/image_1: ... :path/to/image_total + * + * ':' is used as a separator + * '\' is the escaping character for filename containing ':' + */ +static int quorum_open(BlockDriverState *bs, const char *filename, int flags) +{ + BDRVQuorumState *s = bs->opaque; + int i, j, k, len, ret = 0; + char *a, *b, *names; + const char *start; + bool escape; + + /* Parse the quorum: prefix */ + if (!strstart(filename, "quorum:", &start)) { + return -EINVAL; + } + + /* Get threshold */ + ret = quorum_parse_uint_step_next(start, "threshold", '/', + &s->threshold, &a); + if (ret < 0) { + return ret; + } + + /* Get total */ + ret = quorum_parse_uint_step_next(a, "total", ':', &s->total, &b); + if (ret < 0) { + return ret; + } + + if (s->threshold < 1) { + qerror_report(QERR_INVALID_PARAMETER_VALUE, "threshold", "value >= 1"); + return -ERANGE; + } + + if (s->total < 2) { + qerror_report(QERR_INVALID_PARAMETER_VALUE, "total", "value >= 2"); + return -ERANGE; + } + + if (s->threshold > s->total) { + qerror_report(ERROR_CLASS_GENERIC_ERROR, + "threshold <= total must be true"); + return -ERANGE; + } + + s->bs = g_malloc0(sizeof(BlockDriverState *) * s->total); + /* Two allocations for all filenames: simpler to free */ + s->filenames = g_malloc0(sizeof(char *) * s->total); + names = g_strdup(b); + + /* Get the filenames pointers */ + escape = false; + s->filenames[0] = names; + len = strlen(names); + for (i = j = k = 0; i < len && j < s->total; i++) { + /* separation between two files */ + if (!escape && names[i] == ':') { + char *prev = s->filenames[j]; + prev[k] = '\0'; + s->filenames[++j] = prev + k + 1; + k = 0; + continue; + } + + escape = !escape && names[i] == '\\'; + + /* if we are not escaping copy */ + if (!escape) { + s->filenames[j][k++] = names[i]; + } + } + /* terminate last string */ + s->filenames[j][k] = '\0'; + + if ((j + 1) != s->total) { + qerror_report(ERROR_CLASS_GENERIC_ERROR, + "Number of provided file must be equal to total"); + ret = -EINVAL; + goto free_exit; + } + + /* Open files */ + for (i = 0; i < s->total; i++) { + s->bs[i] = bdrv_new(""); + ret = bdrv_open(s->bs[i], s->filenames[i], flags, NULL); + if (ret < 0) { + goto error_exit; + } + } + + goto exit; + +error_exit: + for (; i >= 0; i--) { + bdrv_delete(s->bs[i]); + s->bs[i] = NULL; + } +free_exit: + g_free(s->filenames[0]); + g_free(s->filenames); + s->filenames = NULL; + g_free(s->bs); +exit: + return ret; +} + +static void quorum_close(BlockDriverState *bs) +{ + BDRVQuorumState *s = bs->opaque; + int i; + + for (i = 0; i < s->total; i++) { + /* Ensure writes reach stable storage */ + bdrv_flush(s->bs[i]); + bdrv_delete(s->bs[i]); + } + + g_free(s->filenames[0]); + g_free(s->filenames); + s->filenames = NULL; + g_free(s->bs); +} + static BlockDriver bdrv_quorum = { .format_name = "quorum", .protocol_name = "quorum", .instance_size = sizeof(BDRVQuorumState), + + .bdrv_file_open = quorum_open, + .bdrv_close = quorum_close, }; static void bdrv_quorum_init(void)