{"id":2225141,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2225141/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260420201317.30199-2-junjie.cao@intel.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.1/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260420201317.30199-2-junjie.cao@intel.com>","date":"2026-04-20T20:13:15","name":"[1/3] migration/qemu-file: switch buffer_at functions to positioned I/O _all helpers","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"e6fbdd138f212f2403e77dde2694b266846bc3d5","submitter":{"id":91537,"url":"http://patchwork.ozlabs.org/api/1.1/people/91537/?format=json","name":"Junjie Cao","email":"junjie.cao@intel.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260420201317.30199-2-junjie.cao@intel.com/mbox/","series":[{"id":500601,"url":"http://patchwork.ozlabs.org/api/1.1/series/500601/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=500601","date":"2026-04-20T20:13:15","name":"migration: switch remaining positioned I/O to _all helpers","version":1,"mbox":"http://patchwork.ozlabs.org/series/500601/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2225141/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2225141/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256\n header.s=Intel header.b=SXEpMtJ5;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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Mon, 20 Apr 2026 08:10:23 -0400","from orviesa003.jf.intel.com ([10.64.159.143])\n by orvoesa105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384;\n 20 Apr 2026 05:10:20 -0700","from junjie-optiplex-micro-plus-7010.bj.intel.com ([10.238.152.98])\n by ORVIESA003-auth.jf.intel.com with\n ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Apr 2026 05:10:18 -0700"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple;\n d=intel.com; i=@intel.com; q=dns/txt; s=Intel;\n t=1776687022; x=1808223022;\n h=from:to:cc:subject:date:message-id:in-reply-to:\n references:mime-version:content-transfer-encoding;\n bh=co6/EQDKeNJbkhw8y9V//WgV6dqwIupeKLjGfA2y7iY=;\n b=SXEpMtJ5UqQxpMdbPkGyM0+hY/IqfHSVzFrAWGrzu67P+BTxNVtOZ9p3\n 6Oma0RvlmMYuHR4bYck1SaqYBFVkQdo130jP9GssHEWsDZl1fmQyUPpsb\n OJiMKk8iqYHk5YNyMzj/SjE2zywSLOR9akahNkPOthXrWfpm5WVqEeeaC\n a1CMM5G5+diazWJPzHNV2a5GpH0LHAnJSUhanlWlS2dG1asM8ohuLH6Hk\n khOxnji10zNMJqXY40P6hXtBLC8P2Kuog4iiqYiCbKPGoHKJpHJ58GaEC\n dZvRoTxD3X30i8KxVzxzg1FJcd5W5LZ3V3izaUcBbb2WJpxRvW7PMJgpN Q==;","X-CSE-ConnectionGUID":["dnb50RiMSTejaZSkqJdhUA==","KwNelD88S9S0NFWqQHEElg=="],"X-CSE-MsgGUID":["Ne/jMz14Q3yXDA6BXyCtVg==","8JVGcnV3QB+kHj3nYjU63Q=="],"X-IronPort-AV":["E=McAfee;i=\"6800,10657,11762\"; a=\"88674219\"","E=Sophos;i=\"6.23,189,1770624000\"; d=\"scan'208\";a=\"88674219\"","E=Sophos;i=\"6.23,189,1770624000\"; d=\"scan'208\";a=\"235708261\""],"X-ExtLoop1":"1","From":"Junjie Cao ","To":"qemu-devel@nongnu.org","Cc":"peterx@redhat.com,\n\tfarosas@suse.de,\n\tjunjie.cao@intel.com","Subject":"[PATCH 1/3] migration/qemu-file: switch buffer_at functions to\n positioned I/O _all helpers","Date":"Tue, 21 Apr 2026 04:13:15 +0800","Message-ID":"<20260420201317.30199-2-junjie.cao@intel.com>","X-Mailer":"git-send-email 2.43.0","In-Reply-To":"<20260420201317.30199-1-junjie.cao@intel.com>","References":"<20260420201317.30199-1-junjie.cao@intel.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Received-SPF":"pass client-ip=198.175.65.13;\n envelope-from=junjie.cao@intel.com;\n helo=mgamail.intel.com","X-Spam_score_int":"-24","X-Spam_score":"-2.5","X-Spam_bar":"--","X-Spam_report":"(-2.5 / 5.0 requ) BAYES_00=-1.9, DATE_IN_FUTURE_06_12=1.947,\n DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1,\n DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001,\n 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":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"qemu_put_buffer_at() and qemu_get_buffer_at() have the same pattern as\nthe bug fixed in multifd_file_recv_data(): the ssize_t return value from\nthe channel layer is stored in a size_t variable, and a short transfer\nwould be mishandled rather than retried.\n\nSwitch to qio_channel_pwrite_all() / qio_channel_pread_all() which\nhandle short transfers internally and make the code more robust and\nconsistent with the rest of the positioned I/O call sites.\n\nFixes: 7f5b50a401 (\"migration/qemu-file: add utility methods for working with seekable channels\")\nSigned-off-by: Junjie Cao \n---\n migration/qemu-file.c | 35 +++--------------------------------\n 1 file changed, 3 insertions(+), 32 deletions(-)","diff":"diff --git a/migration/qemu-file.c b/migration/qemu-file.c\nindex 9cf7dc3bd5..9dfb202203 100644\n--- a/migration/qemu-file.c\n+++ b/migration/qemu-file.c\n@@ -535,28 +535,13 @@ void qemu_put_buffer_at(QEMUFile *f, const uint8_t *buf, size_t buflen,\n off_t pos)\n {\n Error *err = NULL;\n- size_t ret;\n \n if (f->last_error) {\n return;\n }\n \n qemu_fflush(f);\n- ret = qio_channel_pwrite(f->ioc, (char *)buf, buflen, pos, &err);\n-\n- if (err) {\n- qemu_file_set_error_obj(f, -EIO, err);\n- return;\n- }\n-\n- if ((ssize_t)ret == QIO_CHANNEL_ERR_BLOCK) {\n- qemu_file_set_error_obj(f, -EAGAIN, NULL);\n- return;\n- }\n-\n- if (ret != buflen) {\n- error_setg(&err, \"Partial write of size %zu, expected %zu\", ret,\n- buflen);\n+ if (qio_channel_pwrite_all(f->ioc, buf, buflen, pos, &err) < 0) {\n qemu_file_set_error_obj(f, -EIO, err);\n return;\n }\n@@ -569,31 +554,17 @@ size_t qemu_get_buffer_at(QEMUFile *f, const uint8_t *buf, size_t buflen,\n off_t pos)\n {\n Error *err = NULL;\n- size_t ret;\n \n if (f->last_error) {\n return 0;\n }\n \n- ret = qio_channel_pread(f->ioc, (char *)buf, buflen, pos, &err);\n-\n- if ((ssize_t)ret == -1 || err) {\n+ if (qio_channel_pread_all(f->ioc, (char *)buf, buflen, pos, &err) < 0) {\n qemu_file_set_error_obj(f, -EIO, err);\n return 0;\n }\n \n- if ((ssize_t)ret == QIO_CHANNEL_ERR_BLOCK) {\n- qemu_file_set_error_obj(f, -EAGAIN, NULL);\n- return 0;\n- }\n-\n- if (ret != buflen) {\n- error_setg(&err, \"Partial read of size %zu, expected %zu\", ret, buflen);\n- qemu_file_set_error_obj(f, -EIO, err);\n- return 0;\n- }\n-\n- return ret;\n+ return buflen;\n }\n \n void qemu_set_offset(QEMUFile *f, off_t off, int whence)\n","prefixes":["1/3"]}