From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00F4DC77B71 for ; Tue, 25 Apr 2023 13:01:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234178AbjDYNB2 (ORCPT ); Tue, 25 Apr 2023 09:01:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234081AbjDYNB1 (ORCPT ); Tue, 25 Apr 2023 09:01:27 -0400 Received: from mail-wr1-x430.google.com (mail-wr1-x430.google.com [IPv6:2a00:1450:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 206C913C05; Tue, 25 Apr 2023 06:01:19 -0700 (PDT) Received: by mail-wr1-x430.google.com with SMTP id ffacd0b85a97d-3023a56048bso4930821f8f.3; Tue, 25 Apr 2023 06:01:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1682427677; x=1685019677; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=h3aCy9dMf9D3o3EUSrkUbK/p5ec0D1Jn7fna+lLcoQQ=; b=Uzi9kyHcvUfeohRfbzFS6j3SyKqBUVSStrt0JfNo4DFBMbrwm4OVfuzZ6CBHq/6acO dnNuoONGvjUwFkFB7Qp8YU/7clcRAOYqoeY7DJd0xf1w3P4Sms1WsvFwI23kwXCVSsyU JXipoEV1CSA/OZmeOxB4B5kaKbqish1u25QPVZwz3tQHs7Vlee7XyBR0kT0XBWKAU3ey pc7EOTHw6ctM20CTMHInlCUp3jbNgGpMOeekldcscHiKainjjX4p5VaHFBmTZghtU86u /aCcgwNJ8IdcKDQe4QsToTYyikYkd/cPE+r3STMM4eoWwRnGTaG+oP/Ln62DN4syp/2E 1m9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1682427677; x=1685019677; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=h3aCy9dMf9D3o3EUSrkUbK/p5ec0D1Jn7fna+lLcoQQ=; b=XZX1D0aL4BNzm2Xc6dSQl5EKkA4DvBplBvYJfHIZSK220W6Admv4iqjsfJxbVhZhI9 zprrtmtoDV6PNtZFQ1saw7PpsUGQYxEdN7L0e6IHLaMsGD6eBpA49WSRMvGuPvLeE27F /EPmwBP2UKhA2Aydwq9HIpkjbYn0qRC5NB6kAhXEPvkwbcAs8quwjS2hOEAQstiy7VsL gS1/hdYUHrEGtkR+JnDBli21XgU4mDZvZdzlsxJhprQSf+m27Ccur2MfDbwcjGPoH4yy FIr1MokLFwjY5xgn2TeSKt66hjw9O51Godp7Iu1+69pvvt6BSbPwlyCoDbjNgSwWt8/X bF1g== X-Gm-Message-State: AAQBX9ePJxrBzI2izGdE2QuBtOD6s4+WPO9vNIUTO7LmNB7Wk3FxAlDh fdJTXXHD7ooGjtiLCKHYIns= X-Google-Smtp-Source: AKy350YK0d9X3+KVdrg5vymnCXFF65tslolfvYk/fpaSb/l6WX7hbUoFoZ7jRflOXqDB8E5Ycr/oJg== X-Received: by 2002:a05:6000:10c8:b0:2f5:b1aa:679c with SMTP id b8-20020a05600010c800b002f5b1aa679cmr11126611wrx.39.1682427677035; Tue, 25 Apr 2023 06:01:17 -0700 (PDT) Received: from amir-ThinkPad-T480.lan ([5.29.249.86]) by smtp.gmail.com with ESMTPSA id s1-20020adff801000000b00300aee6c9cesm13103447wrp.20.2023.04.25.06.01.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Apr 2023 06:01:16 -0700 (PDT) From: Amir Goldstein To: Jan Kara Cc: Christian Brauner , Miklos Szeredi , linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org Subject: [RFC][PATCH 2/4] exportfs: add explicit flag to request non-decodeable file handles Date: Tue, 25 Apr 2023 16:01:03 +0300 Message-Id: <20230425130105.2606684-3-amir73il@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230425130105.2606684-1-amir73il@gmail.com> References: <20230425130105.2606684-1-amir73il@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org So far, all callers of exportfs_encode_inode_fh(), except for fsnotify's show_mark_fhandle(), check that filesystem can decode file handles, but we would like to add more callers that do not require a file handle that can be decoded. Introduce a flag to explicitly request a file handle that may not to be decoded later and a wrapper exportfs_encode_fid() that sets this flag and convert show_mark_fhandle() to use the new wrapper. This will be used to allow adding fanotify support to filesystems that do not support NFS export. Signed-off-by: Amir Goldstein --- Documentation/filesystems/nfs/exporting.rst | 4 ++-- fs/exportfs/expfs.c | 18 ++++++++++++++++-- fs/notify/fanotify/fanotify.c | 4 ++-- fs/notify/fdinfo.c | 2 +- include/linux/exportfs.h | 12 +++++++++++- 5 files changed, 32 insertions(+), 8 deletions(-) diff --git a/Documentation/filesystems/nfs/exporting.rst b/Documentation/filesystems/nfs/exporting.rst index 0e98edd353b5..3d97b8d8f735 100644 --- a/Documentation/filesystems/nfs/exporting.rst +++ b/Documentation/filesystems/nfs/exporting.rst @@ -122,8 +122,8 @@ are exportable by setting the s_export_op field in the struct super_block. This field must point to a "struct export_operations" struct which has the following members: - encode_fh (optional) - Takes a dentry and creates a filehandle fragment which can later be used + encode_fh (optional) + Takes a dentry and creates a filehandle fragment which may later be used to find or create a dentry for the same object. The default implementation creates a filehandle fragment that encodes a 32bit inode and generation number for the inode encoded, and if necessary the diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c index bf1b4925fedd..1b35dda5bdda 100644 --- a/fs/exportfs/expfs.c +++ b/fs/exportfs/expfs.c @@ -381,11 +381,25 @@ static int export_encode_fh(struct inode *inode, struct fid *fid, return type; } +/** + * exportfs_encode_inode_fh - encode a file handle from inode + * @inode: the object to encode + * @fid: where to store the file handle fragment + * @max_len: maximum length to store there + * @flags: properties of the requrested file handle + */ int exportfs_encode_inode_fh(struct inode *inode, struct fid *fid, - int *max_len, struct inode *parent) + int *max_len, struct inode *parent, int flags) { const struct export_operations *nop = inode->i_sb->s_export_op; + /* + * If a decodeable file handle was requested, we need to make sure that + * filesystem can decode file handles. + */ + if (nop && !(flags & EXPORT_FH_FID) && !nop->fh_to_dentry) + return -EOPNOTSUPP; + if (nop && nop->encode_fh) return nop->encode_fh(inode, fid->raw, max_len, parent); @@ -416,7 +430,7 @@ int exportfs_encode_fh(struct dentry *dentry, struct fid *fid, int *max_len, parent = p->d_inode; } - error = exportfs_encode_inode_fh(inode, fid, max_len, parent); + error = exportfs_encode_inode_fh(inode, fid, max_len, parent, flags); dput(p); return error; diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 29bdd99b29fa..d1a49f5b6e6d 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -380,7 +380,7 @@ static int fanotify_encode_fh_len(struct inode *inode) if (!inode) return 0; - exportfs_encode_inode_fh(inode, NULL, &dwords, NULL); + exportfs_encode_inode_fh(inode, NULL, &dwords, NULL, 0); fh_len = dwords << 2; /* @@ -443,7 +443,7 @@ static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode, } dwords = fh_len >> 2; - type = exportfs_encode_inode_fh(inode, buf, &dwords, NULL); + type = exportfs_encode_inode_fh(inode, buf, &dwords, NULL, 0); err = -EINVAL; if (!type || type == FILEID_INVALID || fh_len != dwords << 2) goto out_err; diff --git a/fs/notify/fdinfo.c b/fs/notify/fdinfo.c index 55081ae3a6ec..5c430736ec12 100644 --- a/fs/notify/fdinfo.c +++ b/fs/notify/fdinfo.c @@ -50,7 +50,7 @@ static void show_mark_fhandle(struct seq_file *m, struct inode *inode) f.handle.handle_bytes = sizeof(f.pad); size = f.handle.handle_bytes >> 2; - ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, NULL); + ret = exportfs_encode_fid(inode, (struct fid *)f.handle.f_handle, &size); if ((ret == FILEID_INVALID) || (ret < 0)) { WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret); return; diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h index 2b1048238170..635e89e1dae7 100644 --- a/include/linux/exportfs.h +++ b/include/linux/exportfs.h @@ -136,6 +136,7 @@ struct fid { }; #define EXPORT_FH_CONNECTABLE 0x1 +#define EXPORT_FH_FID 0x2 /** * struct export_operations - for nfsd to communicate with file systems @@ -226,9 +227,18 @@ struct export_operations { }; extern int exportfs_encode_inode_fh(struct inode *inode, struct fid *fid, - int *max_len, struct inode *parent); + int *max_len, struct inode *parent, + int flags); extern int exportfs_encode_fh(struct dentry *dentry, struct fid *fid, int *max_len, int flags); + +static inline int exportfs_encode_fid(struct inode *inode, struct fid *fid, + int *max_len) +{ + return exportfs_encode_inode_fh(inode, fid, max_len, NULL, + EXPORT_FH_FID); +} + extern struct dentry *exportfs_decode_fh_raw(struct vfsmount *mnt, struct fid *fid, int fh_len, int fileid_type, -- 2.34.1