From patchwork Fri Feb 7 09:53:19 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Schoenebeck X-Patchwork-Id: 13964705 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A5536C0219B for ; Fri, 7 Feb 2025 09:58:52 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tgL87-0003pJ-7k; Fri, 07 Feb 2025 04:58:35 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from <0ad7cb925edff3f14bd47fdb7ef3c0b6186960d4@kylie.crudebyte.com>) id 1tgL84-0003jY-Ub for qemu-devel@nongnu.org; Fri, 07 Feb 2025 04:58:33 -0500 Received: from kylie.crudebyte.com ([5.189.157.229]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from <0ad7cb925edff3f14bd47fdb7ef3c0b6186960d4@kylie.crudebyte.com>) id 1tgL83-0001Is-7n for qemu-devel@nongnu.org; Fri, 07 Feb 2025 04:58:32 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=crudebyte.com; s=kylie; h=Cc:To:Subject:Date:From:References:In-Reply-To: Message-Id:Content-Type:Content-Transfer-Encoding:MIME-Version:Content-ID: Content-Description; bh=D9wDRyQBxJlr5I2gWNfNbciP1wRvnJLh7g260qArd8s=; b=hlXCu Exypre/JsL9xnr5yzllWX7zPFkBwGl3BijuZhTHAUw7yXrbnQb/tvE+cT043D5ABsUn+k9BBrEr5f DyFaoFmqgcLywqU/miNb/NGc5FREsq0WSy+OJFvXZlv0Ea6XZpd/Muy943bSbLPlqNknwhYmvRuZu qw9bPQI+K3oEtdSZHy8uSs3sSNtNHXkewY1uxJ81CQKB6BkBmVHpMwl1eoQYeR73yjE/gcz/bhEb9 TCEAx/574362CYdtAHIODwqomiP3GecfVzHhwencUQMjs1o9OfabtGY09VjqcxYXPWDNosszR5ayW e8spUcorRQGjSvjyYFasQfZQNUeQxz985Ix+ljcdvl7bntuDvw0lAmo1cl/d0SHj6n2I2kOGy6pAS qKaWohfvFS7im8KoJn36Ol6UVqGZn6Gyax7Z+S6TnIi1jEefbHs4Bs95r9q8wPb0g4iIhjQzga3vv 4RIvSMjdAOSrQ/zLTk0Tq5SJkkCtXacozl9Oe3Fyuw5OmJrY0kYC2g+zwNICsE9Whf6c2bpO4Dyq7 4KVUuNfjmATpr4p6A+wt6ca2U3KHRegS1IldeabvaCoiJiB05d8G3lX7DdNc9q8qX9QMG8sFJQuZ5 tKirs6GzpTT+imactg63fgKCyYnvkT6lbTyB7l07IPN4eoKt8lUX57IrDlsk6g=; Message-Id: <0ad7cb925edff3f14bd47fdb7ef3c0b6186960d4.1738921999.git.qemu_oss@crudebyte.com> In-Reply-To: References: From: Christian Schoenebeck Date: Fri, 07 Feb 2025 10:53:19 +0100 Subject: [PULL v2 1/4] 9pfs: improve v9fs_walk() tracing To: qemu-devel@nongnu.org, Peter Maydell Cc: Greg Kurz , Stefan Hajnoczi Received-SPF: pass client-ip=5.189.157.229; envelope-from=0ad7cb925edff3f14bd47fdb7ef3c0b6186960d4@kylie.crudebyte.com; helo=kylie.crudebyte.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org 'Twalk' is the most important request type in the 9p protocol to look out for when debugging 9p communication. That's because it is the only part of the 9p protocol which actually deals with human-readable path names, whereas all other 9p request types work on numeric file IDs (FIDs) only. Improve tracing of 'Twalk' requests, e.g. let's say client wanted to walk to "/home/bob/src", then improve trace output from: v9fs_walk tag 0 id 110 fid 0 newfid 1 nwnames 3 to: v9fs_walk tag=0 id=110 fid=0 newfid=1 nwnames=3 wnames={home, bob, src} To achieve this, add a new helper function trace_v9fs_walk_wnames() which converts the received V9fsString array of individual path elements into a comma-separated string presentation for being passed to the tracing system. As this conversion is somewhat expensive, this conversion function is only called if tracing of event 'v9fs_walk' is currently enabled. Signed-off-by: Christian Schoenebeck Reviewed-by: Greg Kurz Reviewed-by: Stefan Hajnoczi Message-Id: --- hw/9pfs/9p.c | 36 +++++++++++++++++++++++++++++++----- hw/9pfs/trace-events | 2 +- 2 files changed, 32 insertions(+), 6 deletions(-) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index 578517739a..6f24c1abb3 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -1774,6 +1774,21 @@ static bool same_stat_id(const struct stat *a, const struct stat *b) return a->st_dev == b->st_dev && a->st_ino == b->st_ino; } +/* + * Returns a (newly allocated) comma-separated string presentation of the + * passed array for logging (tracing) purpose for trace event "v9fs_walk". + * + * It is caller's responsibility to free the returned string. + */ +static char *trace_v9fs_walk_wnames(V9fsString *wnames, size_t nwnames) +{ + g_autofree char **arr = g_malloc0_n(nwnames + 1, sizeof(char *)); + for (size_t i = 0; i < nwnames; ++i) { + arr[i] = wnames[i].data; + } + return g_strjoinv(", ", arr); +} + static void coroutine_fn v9fs_walk(void *opaque) { int name_idx, nwalked; @@ -1787,6 +1802,7 @@ static void coroutine_fn v9fs_walk(void *opaque) size_t offset = 7; int32_t fid, newfid; P9ARRAY_REF(V9fsString) wnames = NULL; + g_autofree char *trace_wnames = NULL; V9fsFidState *fidp; V9fsFidState *newfidp = NULL; V9fsPDU *pdu = opaque; @@ -1800,11 +1816,9 @@ static void coroutine_fn v9fs_walk(void *opaque) } offset += err; - trace_v9fs_walk(pdu->tag, pdu->id, fid, newfid, nwnames); - if (nwnames > P9_MAXWELEM) { err = -EINVAL; - goto out_nofid; + goto out_nofid_nownames; } if (nwnames) { P9ARRAY_NEW(V9fsString, wnames, nwnames); @@ -1814,15 +1828,23 @@ static void coroutine_fn v9fs_walk(void *opaque) for (i = 0; i < nwnames; i++) { err = pdu_unmarshal(pdu, offset, "s", &wnames[i]); if (err < 0) { - goto out_nofid; + goto out_nofid_nownames; } if (name_is_illegal(wnames[i].data)) { err = -ENOENT; - goto out_nofid; + goto out_nofid_nownames; } offset += err; } + if (trace_event_get_state_backends(TRACE_V9FS_WALK)) { + trace_wnames = trace_v9fs_walk_wnames(wnames, nwnames); + trace_v9fs_walk(pdu->tag, pdu->id, fid, newfid, nwnames, + trace_wnames); + } + } else { + trace_v9fs_walk(pdu->tag, pdu->id, fid, newfid, nwnames, ""); } + fidp = get_fid(pdu, fid); if (fidp == NULL) { err = -ENOENT; @@ -1957,7 +1979,11 @@ out: } v9fs_path_free(&dpath); v9fs_path_free(&path); + goto out_pdu_complete; +out_nofid_nownames: + trace_v9fs_walk(pdu->tag, pdu->id, fid, newfid, nwnames, ""); out_nofid: +out_pdu_complete: pdu_complete(pdu, err); } diff --git a/hw/9pfs/trace-events b/hw/9pfs/trace-events index a12e55c165..ed9f4e7209 100644 --- a/hw/9pfs/trace-events +++ b/hw/9pfs/trace-events @@ -11,7 +11,7 @@ v9fs_stat(uint16_t tag, uint8_t id, int32_t fid) "tag %d id %d fid %d" v9fs_stat_return(uint16_t tag, uint8_t id, int32_t mode, int32_t atime, int32_t mtime, int64_t length) "tag %d id %d stat={mode %d atime %d mtime %d length %"PRId64"}" v9fs_getattr(uint16_t tag, uint8_t id, int32_t fid, uint64_t request_mask) "tag %d id %d fid %d request_mask %"PRIu64 v9fs_getattr_return(uint16_t tag, uint8_t id, uint64_t result_mask, uint32_t mode, uint32_t uid, uint32_t gid) "tag %d id %d getattr={result_mask %"PRId64" mode %u uid %u gid %u}" -v9fs_walk(uint16_t tag, uint8_t id, int32_t fid, int32_t newfid, uint16_t nwnames) "tag %d id %d fid %d newfid %d nwnames %d" +v9fs_walk(uint16_t tag, uint8_t id, int32_t fid, int32_t newfid, uint16_t nwnames, const char* wnames) "tag=%d id=%d fid=%d newfid=%d nwnames=%d wnames={%s}" v9fs_walk_return(uint16_t tag, uint8_t id, uint16_t nwnames, void* qids) "tag %d id %d nwnames %d qids %p" v9fs_open(uint16_t tag, uint8_t id, int32_t fid, int32_t mode) "tag %d id %d fid %d mode %d" v9fs_open_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path, int iounit) "tag %u id %u qid={type %u version %u path %"PRIu64"} iounit %d" From patchwork Fri Feb 7 09:53:19 2025 Content-Type: text/plain; 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Message-Id: In-Reply-To: References: From: Christian Schoenebeck Date: Fri, 07 Feb 2025 10:53:19 +0100 Subject: [PULL v2 2/4] 9pfs: make multidevs=remap default To: qemu-devel@nongnu.org, Peter Maydell Cc: Greg Kurz , Stefan Hajnoczi Received-SPF: pass client-ip=5.189.157.229; envelope-from=a2f17bd40b3d302f6c1ddf0da75d2343966e0a3f@kylie.crudebyte.com; helo=kylie.crudebyte.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org 1a6ed33cc5 introduced option multidevs=remap|forbid|warn and made "warn" the default option. As it turned out though, e.g. by several reports in conjunction with following 9p client issue: https://github.com/torvalds/linux/commit/850925a8133c73c4a2453c360b2c3beb3bab67c9 Many people are just ignoring this warning, or even do not notice the warning at all. Therefore make multidevs=remap the new default option to prevent people to run into such kind of severe misbehaviours in the first place. From performance PoV the runtime overhead of multidevs=remap is neglectable with few or even just only one device being shared with the same 9p export, expected to be constant Theta(1). The inode numbers emitted to guest also just loose one bit (since 6b6aa8285d) for the 1st device being shared. Signed-off-by: Christian Schoenebeck Message-Id: <09cc84e5561f66b6a8cf49b3532c6c78a6acc806.1734876877.git.qemu_oss@crudebyte.com> --- hw/9pfs/9p-local.c | 3 +++ qemu-options.hx | 49 +++++++++++++++++++++++++--------------------- 2 files changed, 30 insertions(+), 22 deletions(-) diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c index 1b1f3b9ec8..928523afcc 100644 --- a/hw/9pfs/9p-local.c +++ b/hw/9pfs/9p-local.c @@ -1538,6 +1538,9 @@ static int local_parse_opts(QemuOpts *opts, FsDriverEntry *fse, Error **errp) "[remap|forbid|warn]\n"); return -1; } + } else { + fse->export_flags &= ~V9FS_FORBID_MULTIDEVS; + fse->export_flags |= V9FS_REMAP_INODES; } if (!path) { diff --git a/qemu-options.hx b/qemu-options.hx index ec0090dfe2..1b26ad53bd 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -1951,32 +1951,37 @@ SRST Specifies the tag name to be used by the guest to mount this export point. - ``multidevs=multidevs`` - Specifies how to deal with multiple devices being shared with a - 9p export. Supported behaviours are either "remap", "forbid" or - "warn". The latter is the default behaviour on which virtfs 9p - expects only one device to be shared with the same export, and - if more than one device is shared and accessed via the same 9p - export then only a warning message is logged (once) by qemu on - host side. In order to avoid file ID collisions on guest you - should either create a separate virtfs export for each device to - be shared with guests (recommended way) or you might use "remap" - instead which allows you to share multiple devices with only one - export instead, which is achieved by remapping the original - inode numbers from host to guest in a way that would prevent - such collisions. Remapping inodes in such use cases is required + ``multidevs=remap|forbid|warn`` + Specifies how to deal with multiple devices being shared with + the same 9p export in order to avoid file ID collisions on guest. + Supported behaviours are either "remap" (default), "forbid" or + "warn". + + ``remap`` : assumes the possibility that more than one device is + shared with the same 9p export. Therefore inode numbers from host + are remapped for guest in a way that would prevent file ID + collisions on guest. Remapping inodes in such cases is required because the original device IDs from host are never passed and exposed on guest. Instead all files of an export shared with - virtfs always share the same device id on guest. So two files + virtfs always share the same device ID on guest. So two files with identical inode numbers but from actually different devices on host would otherwise cause a file ID collision and hence - potential misbehaviours on guest. "forbid" on the other hand - assumes like "warn" that only one device is shared by the same - export, however it will not only log a warning message but also - deny access to additional devices on guest. Note though that - "forbid" does currently not block all possible file access - operations (e.g. readdir() would still return entries from other - devices). + potential severe misbehaviours on guest. + + ``warn`` : virtfs 9p expects only one device to be shared with + the same export. If however more than one device is shared and + accessed via the same 9p export then only a warning message is + logged (once) by qemu on host side. No further action is performed + in this case that would prevent file ID collisions on guest. This + could thus lead to severe misbehaviours in this case like wrong + files being accessed and data corruption on the exported tree. + + ``forbid`` : assumes like "warn" that only one device is shared + by the same 9p export, however it will not only log a warning + message but also deny access to additional devices on guest. Note + though that "forbid" does currently not block all possible file + access operations (e.g. readdir() would still return entries from + other devices). ERST DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, From patchwork Fri Feb 7 09:53:19 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Schoenebeck X-Patchwork-Id: 13964706 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9D10BC02196 for ; Fri, 7 Feb 2025 09:58:52 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tgL8K-00041c-KJ; Fri, 07 Feb 2025 04:58:48 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from <9a0dd4b3e4e0b06ec35c5ac370f54a36ea1846ed@kylie.crudebyte.com>) id 1tgL8H-0003uW-7X for qemu-devel@nongnu.org; Fri, 07 Feb 2025 04:58:45 -0500 Received: from kylie.crudebyte.com ([5.189.157.229]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from <9a0dd4b3e4e0b06ec35c5ac370f54a36ea1846ed@kylie.crudebyte.com>) id 1tgL8F-0001KE-CY for qemu-devel@nongnu.org; Fri, 07 Feb 2025 04:58:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=crudebyte.com; s=kylie; h=Cc:To:Subject:Date:From:References:In-Reply-To: Message-Id:Content-Type:Content-Transfer-Encoding:MIME-Version:Content-ID: Content-Description; bh=647mmsLP3uA3INY74GivlMfueppYt8qBzVKkJaljaRo=; b=EXx4p AWH3yB61T6D5l96cN6mWGyCniam89WVJqri1xl6nG4++0HdVqTHJcXd4mXd5geIirPrveIP/oWhsj plGIzyNHZv6BsiK1DlSamaVv23htIbfMx2OzitYTp4z/GTTu/IsJXppni7+5ufiYCo06m/fjuLKFb mqenQtYZqxVOMzr5I0wFMg7myvVLmAuYZhL3u3co0qM5UiEdrTh8Y+SM+su/gY/F+XS3SjLmuKOlX xAGJiNq2ajB6Dh96uvoVPP6/5fEPCXl/+kaCOUNbwXPB+7b7J7vDKBlm5GbpcSlaCTxCUK1N/W6Sh h6sJpT0i3T2Z/IVGrB1Td6D/0nUFazMjJUTq8vkfqQgjHPGpJ93EWn5dSLRj99mGQBKhnSpXSghfu 9geOWQ8tX+qxTMC3vIsAHMdgbcT6EeDsPwwIrIGzr3eqOMv6DagoLoQgoLQmH39Hcc2uFCxu9oErD j5JME/qjnWKv5MAgzGqf7k4asVaVUT/HH6OkcFyl14SF34UXbereVNZBjw/ev4iFJGqA20FoP2cPd 1iEbVwAHDnO7JRy0bhl5UgeQX9TYucA9LWI2o+3ihZtX/8RPDKhb7IHm9MTIKaZltWPv4Pm6u0F18 7QEeRnEhVtM7S0UXZPiMEMDyIH1xx9QYe53Closvo7CTDPn8YiN3TA5CGtOcFw=; Message-Id: <9a0dd4b3e4e0b06ec35c5ac370f54a36ea1846ed.1738921999.git.qemu_oss@crudebyte.com> In-Reply-To: References: From: Christian Schoenebeck Date: Fri, 07 Feb 2025 10:53:19 +0100 Subject: [PULL v2 3/4] 9pfs: improve v9fs_open() tracing To: qemu-devel@nongnu.org, Peter Maydell Cc: Greg Kurz , Stefan Hajnoczi Received-SPF: pass client-ip=5.189.157.229; envelope-from=9a0dd4b3e4e0b06ec35c5ac370f54a36ea1846ed@kylie.crudebyte.com; helo=kylie.crudebyte.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Improve tracing of 9p 'Topen' request type by showing open() flags as human-readable text. E.g. trace output: v9fs_open tag 0 id 12 fid 2 mode 100352 would become: v9fs_open tag=0 id=12 fid=2 mode=100352(RDONLY|NONBLOCK|DIRECTORY| TMPFILE|NDELAY) Therefor add a new utility function qemu_open_flags_tostr() that converts numeric open() flags from host's native O_* flag constants to a string presentation. 9p2000.L and 9p2000.u protocol variants use different numeric 'mode' constants for 'Topen' requests. Instead of writing string conversion code for both protocol variants, use the already existing conversion functions that convert the mode flags from respective protocol constants to host's native open() numeric flag constants and pass that result to the new string conversion function qemu_open_flags_tostr(). Signed-off-by: Christian Schoenebeck Message-Id: --- hw/9pfs/9p-util-generic.c | 50 +++++++++++++++++++++++++++++++++++++++ hw/9pfs/9p-util.h | 6 +++++ hw/9pfs/9p.c | 9 ++++++- hw/9pfs/meson.build | 1 + hw/9pfs/trace-events | 2 +- 5 files changed, 66 insertions(+), 2 deletions(-) create mode 100644 hw/9pfs/9p-util-generic.c diff --git a/hw/9pfs/9p-util-generic.c b/hw/9pfs/9p-util-generic.c new file mode 100644 index 0000000000..4c1e9c887d --- /dev/null +++ b/hw/9pfs/9p-util-generic.c @@ -0,0 +1,50 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#include "qemu/osdep.h" +#include "9p-util.h" +#include + +char *qemu_open_flags_tostr(int flags) +{ + int acc = flags & O_ACCMODE; + return g_strconcat( + (acc == O_WRONLY) ? "WRONLY" : (acc == O_RDONLY) ? "RDONLY" : "RDWR", + (flags & O_CREAT) ? "|CREAT" : "", + (flags & O_EXCL) ? "|EXCL" : "", + (flags & O_NOCTTY) ? "|NOCTTY" : "", + (flags & O_TRUNC) ? "|TRUNC" : "", + (flags & O_APPEND) ? "|APPEND" : "", + (flags & O_NONBLOCK) ? "|NONBLOCK" : "", + (flags & O_DSYNC) ? "|DSYNC" : "", + #ifdef O_DIRECT + (flags & O_DIRECT) ? "|DIRECT" : "", + #endif + (flags & O_LARGEFILE) ? "|LARGEFILE" : "", + (flags & O_DIRECTORY) ? "|DIRECTORY" : "", + (flags & O_NOFOLLOW) ? "|NOFOLLOW" : "", + #ifdef O_NOATIME + (flags & O_NOATIME) ? "|NOATIME" : "", + #endif + #ifdef O_CLOEXEC + (flags & O_CLOEXEC) ? "|CLOEXEC" : "", + #endif + #ifdef __O_SYNC + (flags & __O_SYNC) ? "|SYNC" : "", + #else + ((flags & O_SYNC) == O_SYNC) ? "|SYNC" : "", + #endif + #ifdef O_PATH + (flags & O_PATH) ? "|PATH" : "", + #endif + #ifdef __O_TMPFILE + (flags & __O_TMPFILE) ? "|TMPFILE" : "", + #elif defined(O_TMPFILE) + ((flags & O_TMPFILE) == O_TMPFILE) ? "|TMPFILE" : "", + #endif + /* O_NDELAY is usually just an alias of O_NONBLOCK */ + #if defined(O_NDELAY) && O_NDELAY != O_NONBLOCK + (flags & O_NDELAY) ? "|NDELAY" : "", + #endif + NULL /* always last (required NULL termination) */ + ); +} diff --git a/hw/9pfs/9p-util.h b/hw/9pfs/9p-util.h index 95ee4da9bd..7bc4ec8e85 100644 --- a/hw/9pfs/9p-util.h +++ b/hw/9pfs/9p-util.h @@ -267,4 +267,10 @@ int pthread_fchdir_np(int fd) __attribute__((weak_import)); #endif int qemu_mknodat(int dirfd, const char *filename, mode_t mode, dev_t dev); +/* + * Returns a newly allocated string presentation of open() flags, intended + * for debugging (tracing) purposes only. + */ +char *qemu_open_flags_tostr(int flags); + #endif diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index 6f24c1abb3..7cad2bce62 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -2008,6 +2008,7 @@ static void coroutine_fn v9fs_open(void *opaque) V9fsFidState *fidp; V9fsPDU *pdu = opaque; V9fsState *s = pdu->s; + g_autofree char *trace_oflags = NULL; if (s->proto_version == V9FS_PROTO_2000L) { err = pdu_unmarshal(pdu, offset, "dd", &fid, &mode); @@ -2019,7 +2020,13 @@ static void coroutine_fn v9fs_open(void *opaque) if (err < 0) { goto out_nofid; } - trace_v9fs_open(pdu->tag, pdu->id, fid, mode); + if (trace_event_get_state_backends(TRACE_V9FS_OPEN)) { + trace_oflags = qemu_open_flags_tostr( + (s->proto_version == V9FS_PROTO_2000L) ? + dotl_to_open_flags(mode) : omode_to_uflags(mode) + ); + trace_v9fs_open(pdu->tag, pdu->id, fid, mode, trace_oflags); + } fidp = get_fid(pdu, fid); if (fidp == NULL) { diff --git a/hw/9pfs/meson.build b/hw/9pfs/meson.build index eceffdb81e..d35d4f44ff 100644 --- a/hw/9pfs/meson.build +++ b/hw/9pfs/meson.build @@ -3,6 +3,7 @@ fs_ss.add(files( '9p-local.c', '9p-posix-acl.c', '9p-synth.c', + '9p-util-generic.c', '9p-xattr-user.c', '9p-xattr.c', '9p.c', diff --git a/hw/9pfs/trace-events b/hw/9pfs/trace-events index ed9f4e7209..0e0fc37261 100644 --- a/hw/9pfs/trace-events +++ b/hw/9pfs/trace-events @@ -13,7 +13,7 @@ v9fs_getattr(uint16_t tag, uint8_t id, int32_t fid, uint64_t request_mask) "tag v9fs_getattr_return(uint16_t tag, uint8_t id, uint64_t result_mask, uint32_t mode, uint32_t uid, uint32_t gid) "tag %d id %d getattr={result_mask %"PRId64" mode %u uid %u gid %u}" v9fs_walk(uint16_t tag, uint8_t id, int32_t fid, int32_t newfid, uint16_t nwnames, const char* wnames) "tag=%d id=%d fid=%d newfid=%d nwnames=%d wnames={%s}" v9fs_walk_return(uint16_t tag, uint8_t id, uint16_t nwnames, void* qids) "tag %d id %d nwnames %d qids %p" -v9fs_open(uint16_t tag, uint8_t id, int32_t fid, int32_t mode) "tag %d id %d fid %d mode %d" +v9fs_open(uint16_t tag, uint8_t id, int32_t fid, int32_t mode, const char* oflags) "tag=%d id=%d fid=%d mode=%d(%s)" v9fs_open_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path, int iounit) "tag %u id %u qid={type %u version %u path %"PRIu64"} iounit %d" v9fs_lcreate(uint16_t tag, uint8_t id, int32_t dfid, int32_t flags, int32_t mode, uint32_t gid) "tag %d id %d dfid %d flags %d mode %d gid %u" v9fs_lcreate_return(uint16_t tag, uint8_t id, uint8_t type, uint32_t version, uint64_t path, int32_t iounit) "tag %u id %u qid={type %u version %u path %"PRIu64"} iounit %d" From patchwork Fri Feb 7 09:53:19 2025 Content-Type: text/plain; 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Message-Id: <52065d405ae96221f15b0fd9c099437c77178d4f.1738921999.git.qemu_oss@crudebyte.com> In-Reply-To: References: From: Christian Schoenebeck Date: Fri, 07 Feb 2025 10:53:19 +0100 Subject: [PULL v2 4/4] MAINTAINERS: Mark me as reviewer only for 9pfs To: qemu-devel@nongnu.org, Peter Maydell Cc: Greg Kurz , Stefan Hajnoczi Received-SPF: pass client-ip=5.189.157.229; envelope-from=52065d405ae96221f15b0fd9c099437c77178d4f@kylie.crudebyte.com; helo=kylie.crudebyte.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Greg Kurz I still review 9pfs changes from time to time but I'm definitely not able to do actual maintainer work. Drop my tree on the way as I'll obviously not use it anymore, and it has been left untouched since May 2020. Signed-off-by: Greg Kurz Reviewed-by: Christian Schoenebeck Message-Id: <20250115100849.259612-1-groug@kaod.org> Signed-off-by: Christian Schoenebeck --- MAINTAINERS | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/MAINTAINERS b/MAINTAINERS index 0cf37fce7b..c6859cbb0e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2254,8 +2254,8 @@ F: include/system/balloon.h F: tests/qtest/virtio-balloon-test.c virtio-9p -M: Greg Kurz M: Christian Schoenebeck +R: Greg Kurz S: Maintained W: https://wiki.qemu.org/Documentation/9p F: hw/9pfs/ @@ -2263,7 +2263,6 @@ X: hw/9pfs/xen-9p* F: fsdev/ F: tests/qtest/virtio-9p-test.c F: tests/qtest/libqos/virtio-9p* -T: git https://gitlab.com/gkurz/qemu.git 9p-next T: git https://github.com/cschoenebeck/qemu.git 9p.next virtio-blk