From patchwork Wed Jan 29 16:00:31 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabiano Rosas X-Patchwork-Id: 13953887 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 9F189C0218D for ; Wed, 29 Jan 2025 16:04:07 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tdAXZ-0006GH-LV; Wed, 29 Jan 2025 11:03:45 -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 ) id 1tdAVX-0003HY-V9 for qemu-devel@nongnu.org; Wed, 29 Jan 2025 11:01:52 -0500 Received: from smtp-out2.suse.de ([2a07:de40:b251:101:10:150:64:2]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1tdAVU-0005I0-QU for qemu-devel@nongnu.org; Wed, 29 Jan 2025 11:01:38 -0500 Received: from imap1.dmz-prg2.suse.org (imap1.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 5703F1F365; Wed, 29 Jan 2025 16:01:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1738166495; h=from:from:reply-to: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=NBNZtSiI+Z0X4jH0jdTf9Edwx+1OSMQPOSIcGOrxR9A=; b=jfVycR95vFsR/QMhhtZVUTwCZ0UNZtUE7vE5YS2R/nEv/Cdeg4fl0eSDtc8p9GASfgX6Gd 8HeqgdWArGAOmaMEc9kRPmXKzcQgpcKhKiToMgipgIU7FUYaE8Q4Nbt4nK53cXVKyOGBBx mf7lFmmWVtDzzFPkHkZb04o05a3js3Y= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1738166495; h=from:from:reply-to: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=NBNZtSiI+Z0X4jH0jdTf9Edwx+1OSMQPOSIcGOrxR9A=; b=oqSVdwLgQtNTXoBhSgtnbTNxQKo6+gWcgC0kjGPaDb06hW7O2Cgx6izgFr1lU0XEDg8DoL E2TVGl9RaC3YCSBA== Authentication-Results: smtp-out2.suse.de; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=jfVycR95; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=oqSVdwLg DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1738166495; h=from:from:reply-to: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=NBNZtSiI+Z0X4jH0jdTf9Edwx+1OSMQPOSIcGOrxR9A=; b=jfVycR95vFsR/QMhhtZVUTwCZ0UNZtUE7vE5YS2R/nEv/Cdeg4fl0eSDtc8p9GASfgX6Gd 8HeqgdWArGAOmaMEc9kRPmXKzcQgpcKhKiToMgipgIU7FUYaE8Q4Nbt4nK53cXVKyOGBBx mf7lFmmWVtDzzFPkHkZb04o05a3js3Y= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1738166495; h=from:from:reply-to: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=NBNZtSiI+Z0X4jH0jdTf9Edwx+1OSMQPOSIcGOrxR9A=; b=oqSVdwLgQtNTXoBhSgtnbTNxQKo6+gWcgC0kjGPaDb06hW7O2Cgx6izgFr1lU0XEDg8DoL E2TVGl9RaC3YCSBA== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 0E478137DB; Wed, 29 Jan 2025 16:01:33 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id 4BQIMN1QmmffPAAAD6G6ig (envelope-from ); Wed, 29 Jan 2025 16:01:33 +0000 From: Fabiano Rosas To: qemu-devel@nongnu.org Cc: Peter Xu , Steve Sistare Subject: [PULL 14/42] migration: SCM_RIGHTS for QEMUFile Date: Wed, 29 Jan 2025 13:00:31 -0300 Message-Id: <20250129160059.6987-15-farosas@suse.de> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20250129160059.6987-1-farosas@suse.de> References: <20250129160059.6987-1-farosas@suse.de> MIME-Version: 1.0 X-Spamd-Result: default: False [5.36 / 50.00]; BAYES_SPAM(5.07)[99.91%]; MID_CONTAINS_FROM(1.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_MISSING_CHARSET(0.50)[]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; BAD_REP_POLICIES(0.10)[]; MX_GOOD(-0.01)[]; RCVD_COUNT_TWO(0.00)[2]; FUZZY_BLOCKED(0.00)[rspamd.com]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from]; MIME_TRACE(0.00)[0:+]; TO_DN_SOME(0.00)[]; ARC_NA(0.00)[]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; R_DKIM_ALLOW(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; RCVD_VIA_SMTP_AUTH(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; FROM_EQ_ENVFROM(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; FROM_HAS_DN(0.00)[]; RCVD_TLS_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:email, suse.de:dkim, suse.de:mid, oracle.com:email] X-Spamd-Bar: +++++ X-Rspamd-Queue-Id: 5703F1F365 X-Rspamd-Action: no action X-Rspamd-Server: rspamd2.dmz-prg2.suse.org Received-SPF: pass client-ip=2a07:de40:b251:101:10:150:64:2; envelope-from=farosas@suse.de; helo=smtp-out2.suse.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 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_DNSWL_MED=-2.3, SPF_HELO_NONE=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: Steve Sistare Define functions to put/get file descriptors to/from a QEMUFile, for qio channels that support SCM_RIGHTS. Maintain ordering such that put(A), put(fd), put(B) followed by get(A), get(fd), get(B) always succeeds. Other get orderings may succeed but are not guaranteed. Signed-off-by: Steve Sistare Reviewed-by: Peter Xu Link: https://lore.kernel.org/r/1736967650-129648-14-git-send-email-steven.sistare@oracle.com Signed-off-by: Fabiano Rosas --- migration/qemu-file.c | 84 ++++++++++++++++++++++++++++++++++++++++-- migration/qemu-file.h | 2 + migration/trace-events | 2 + 3 files changed, 84 insertions(+), 4 deletions(-) diff --git a/migration/qemu-file.c b/migration/qemu-file.c index b6d2f588bd..1303a5bf58 100644 --- a/migration/qemu-file.c +++ b/migration/qemu-file.c @@ -37,6 +37,11 @@ #define IO_BUF_SIZE 32768 #define MAX_IOV_SIZE MIN_CONST(IOV_MAX, 64) +typedef struct FdEntry { + QTAILQ_ENTRY(FdEntry) entry; + int fd; +} FdEntry; + struct QEMUFile { QIOChannel *ioc; bool is_writable; @@ -51,6 +56,9 @@ struct QEMUFile { int last_error; Error *last_error_obj; + + bool can_pass_fd; + QTAILQ_HEAD(, FdEntry) fds; }; /* @@ -109,6 +117,8 @@ static QEMUFile *qemu_file_new_impl(QIOChannel *ioc, bool is_writable) object_ref(ioc); f->ioc = ioc; f->is_writable = is_writable; + f->can_pass_fd = qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS); + QTAILQ_INIT(&f->fds); return f; } @@ -310,6 +320,10 @@ static ssize_t coroutine_mixed_fn qemu_fill_buffer(QEMUFile *f) int len; int pending; Error *local_error = NULL; + g_autofree int *fds = NULL; + size_t nfd = 0; + int **pfds = f->can_pass_fd ? &fds : NULL; + size_t *pnfd = f->can_pass_fd ? &nfd : NULL; assert(!qemu_file_is_writable(f)); @@ -325,10 +339,9 @@ static ssize_t coroutine_mixed_fn qemu_fill_buffer(QEMUFile *f) } do { - len = qio_channel_read(f->ioc, - (char *)f->buf + pending, - IO_BUF_SIZE - pending, - &local_error); + struct iovec iov = { f->buf + pending, IO_BUF_SIZE - pending }; + len = qio_channel_readv_full(f->ioc, &iov, 1, pfds, pnfd, 0, + &local_error); if (len == QIO_CHANNEL_ERR_BLOCK) { if (qemu_in_coroutine()) { qio_channel_yield(f->ioc, G_IO_IN); @@ -348,9 +361,66 @@ static ssize_t coroutine_mixed_fn qemu_fill_buffer(QEMUFile *f) qemu_file_set_error_obj(f, len, local_error); } + for (int i = 0; i < nfd; i++) { + FdEntry *fde = g_new0(FdEntry, 1); + fde->fd = fds[i]; + QTAILQ_INSERT_TAIL(&f->fds, fde, entry); + } + return len; } +int qemu_file_put_fd(QEMUFile *f, int fd) +{ + int ret = 0; + QIOChannel *ioc = qemu_file_get_ioc(f); + Error *err = NULL; + struct iovec iov = { (void *)" ", 1 }; + + /* + * Send a dummy byte so qemu_fill_buffer on the receiving side does not + * fail with a len=0 error. Flush first to maintain ordering wrt other + * data. + */ + + qemu_fflush(f); + if (qio_channel_writev_full(ioc, &iov, 1, &fd, 1, 0, &err) < 1) { + error_report_err(error_copy(err)); + qemu_file_set_error_obj(f, -EIO, err); + ret = -1; + } + trace_qemu_file_put_fd(f->ioc->name, fd, ret); + return ret; +} + +int qemu_file_get_fd(QEMUFile *f) +{ + int fd = -1; + FdEntry *fde; + + if (!f->can_pass_fd) { + Error *err = NULL; + error_setg(&err, "%s does not support fd passing", f->ioc->name); + error_report_err(error_copy(err)); + qemu_file_set_error_obj(f, -EIO, err); + goto out; + } + + /* Force the dummy byte and its fd passenger to appear. */ + qemu_peek_byte(f, 0); + + fde = QTAILQ_FIRST(&f->fds); + if (fde) { + qemu_get_byte(f); /* Drop the dummy byte */ + fd = fde->fd; + QTAILQ_REMOVE(&f->fds, fde, entry); + g_free(fde); + } +out: + trace_qemu_file_get_fd(f->ioc->name, fd); + return fd; +} + /** Closes the file * * Returns negative error value if any error happened on previous operations or @@ -361,11 +431,17 @@ static ssize_t coroutine_mixed_fn qemu_fill_buffer(QEMUFile *f) */ int qemu_fclose(QEMUFile *f) { + FdEntry *fde, *next; int ret = qemu_fflush(f); int ret2 = qio_channel_close(f->ioc, NULL); if (ret >= 0) { ret = ret2; } + QTAILQ_FOREACH_SAFE(fde, &f->fds, entry, next) { + warn_report("qemu_fclose: received fd %d was never claimed", fde->fd); + close(fde->fd); + g_free(fde); + } g_clear_pointer(&f->ioc, object_unref); error_free(f->last_error_obj); g_free(f); diff --git a/migration/qemu-file.h b/migration/qemu-file.h index 11c2120edd..3e47a20621 100644 --- a/migration/qemu-file.h +++ b/migration/qemu-file.h @@ -79,5 +79,7 @@ size_t qemu_get_buffer_at(QEMUFile *f, const uint8_t *buf, size_t buflen, off_t pos); QIOChannel *qemu_file_get_ioc(QEMUFile *file); +int qemu_file_put_fd(QEMUFile *f, int fd); +int qemu_file_get_fd(QEMUFile *f); #endif diff --git a/migration/trace-events b/migration/trace-events index 4e3061bc55..abd9cdf2a1 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -88,6 +88,8 @@ put_qlist_end(const char *field_name, const char *vmsd_name) "%s(%s)" # qemu-file.c qemu_file_fclose(void) "" +qemu_file_put_fd(const char *name, int fd, int ret) "ioc %s, fd %d -> status %d" +qemu_file_get_fd(const char *name, int fd) "ioc %s -> fd %d" # ram.c get_queued_page(const char *block_name, uint64_t tmp_offset, unsigned long page_abs) "%s/0x%" PRIx64 " page_abs=0x%lx"