From patchwork Fri Feb 3 09:18:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 13127251 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.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 21BDBC61DA4 for ; Fri, 3 Feb 2023 09:18:41 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.489059.757396 (Exim 4.92) (envelope-from ) id 1pNsDH-0007oO-Gn; Fri, 03 Feb 2023 09:18:31 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 489059.757396; Fri, 03 Feb 2023 09:18:31 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pNsDH-0007oF-D1; Fri, 03 Feb 2023 09:18:31 +0000 Received: by outflank-mailman (input) for mailman id 489059; Fri, 03 Feb 2023 09:18:29 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pNsDF-0006sG-OB for xen-devel@lists.xenproject.org; Fri, 03 Feb 2023 09:18:29 +0000 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id b8a0311c-a3a3-11ed-933c-83870f6b2ba8; Fri, 03 Feb 2023 10:18:29 +0100 (CET) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 079943447D; Fri, 3 Feb 2023 09:18:29 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id D2CB01346D; Fri, 3 Feb 2023 09:18:28 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id Jm4sMmTR3GMkEwAAMHmgww (envelope-from ); Fri, 03 Feb 2023 09:18:28 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: b8a0311c-a3a3-11ed-933c-83870f6b2ba8 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1675415909; 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=GtWQKRAyY57feFJk8BbUzmL2nez/i6gSp+ydtlu7X9A=; b=W2spmIMlIzYekMsW/Nktfe/U0VVGVGHAsO/wqtUDQBwSfMriG+gLhv4eU8qX16ZeD2kqxU ZwKQEMJBklXMCsymSYU8e5wjFP83bBCQJHQuI898uqC2ZZh+HcL+lDyUoAEP0pp2V4jebs xzCkqi97iujyPKCo0BapNivCn+zUZbs= From: Juergen Gross To: minios-devel@lists.xenproject.org, xen-devel@lists.xenproject.org Cc: samuel.thibault@ens-lyon.org, wl@xen.org, Juergen Gross Subject: [PATCH 3/7] Mini-OS: add support for runtime mounts Date: Fri, 3 Feb 2023 10:18:05 +0100 Message-Id: <20230203091809.14478-4-jgross@suse.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20230203091809.14478-1-jgross@suse.com> References: <20230203091809.14478-1-jgross@suse.com> MIME-Version: 1.0 Add the support to mount a device at runtime. The number of dynamic mounts is limited by a #define. For devices supporting multiple files struct file is modified to hold a pointer to file specific data in contrast to device specific data. Signed-off-by: Juergen Gross Reviewed-by: Samuel Thibault --- include/lib.h | 5 +++++ lib/sys.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 54 insertions(+), 1 deletion(-) diff --git a/include/lib.h b/include/lib.h index 36d94ec4..fd8c36de 100644 --- a/include/lib.h +++ b/include/lib.h @@ -172,6 +172,7 @@ struct file { union { int fd; /* Any fd from an upper layer. */ void *dev; + void *filedata; }; }; @@ -194,6 +195,10 @@ struct mount_point { void *dev; }; +int mount(const char *path, void *dev, + int (*open)(struct mount_point *, const char *, int, mode_t)); +void umount(const char *path); + unsigned int alloc_file_type(const struct file_ops *ops); off_t lseek_default(struct file *file, off_t offset, int whence); diff --git a/lib/sys.c b/lib/sys.c index 1475c621..4171bfd6 100644 --- a/lib/sys.c +++ b/lib/sys.c @@ -339,7 +339,14 @@ static int open_mem(struct mount_point *mnt, const char *pathname, int flags, return fd; } -static struct mount_point mount_points[] = { +#ifdef CONFIG_CONSFRONT +#define STATIC_MNTS 4 +#else +#define STATIC_MNTS 2 +#endif +#define DYNAMIC_MNTS 8 + +static struct mount_point mount_points[STATIC_MNTS + DYNAMIC_MNTS] = { { .path = "/var/log", .open = open_log, .dev = NULL }, { .path = "/dev/mem", .open = open_mem, .dev = NULL }, #ifdef CONFIG_CONSFRONT @@ -365,6 +372,8 @@ int open(const char *pathname, int flags, ...) for ( m = 0; m < ARRAY_SIZE(mount_points); m++ ) { mnt = mount_points + m; + if ( !mnt->path ) + continue; mlen = strlen(mnt->path); if ( !strncmp(pathname, mnt->path, mlen) && (pathname[mlen] == '/' || pathname[mlen] == 0) ) @@ -375,6 +384,45 @@ int open(const char *pathname, int flags, ...) return -1; } +int mount(const char *path, void *dev, + int (*open)(struct mount_point *, const char *, int, mode_t)) +{ + unsigned int m; + struct mount_point *mnt; + + for ( m = 0; m < ARRAY_SIZE(mount_points); m++ ) + { + mnt = mount_points + m; + if ( !mnt->path ) + { + mnt->path = strdup(path); + mnt->open = open; + mnt->dev = dev; + return 0; + } + } + + errno = ENOSPC; + return -1; +} + +void umount(const char *path) +{ + unsigned int m; + struct mount_point *mnt; + + for ( m = 0; m < ARRAY_SIZE(mount_points); m++ ) + { + mnt = mount_points + m; + if ( mnt->path && !strcmp(mnt->path, path) ) + { + free((char *)mnt->path); + mnt->path = NULL; + return; + } + } +} + int isatty(int fd) { return files[fd].type == FTYPE_CONSOLE;