From patchwork Fri Aug 23 00:01:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 13774346 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3F1BF365; Fri, 23 Aug 2024 00:01:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724371283; cv=none; b=O9ErjQttZdB0Bts+I0OH1wOie8V7ljk3cSud/FIMHePvHGi99IGPCx7o6ES5u+oUDGuPh+H21n1WwKpjxVea+Wize5l7wmEpYA4ChbTYbz/nPLkNUfdAXZd22XLWrMXAuNVlzdYQZkuPEmqaD51+woQyz3EfQryCK10YvEfKt2U= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724371283; c=relaxed/simple; bh=46LiIuR6+JpkDUb8HzN7eFEsw9pn6pg7fd3b5GOs39k=; h=Date:Subject:From:To:Cc:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=dIb8WzKOjfqaHulNdnSOi6wjsh23hWJYkozYfiEHlEZS/1PM95SFzamgGikKDvabGMakvRBZqsnA7++QRjX60r4CPnJq2b4GUOTCTWn1gdyBrpKGDICH2E5i9cVCFuf4zPA4YHCyyfGrHaGIq0zwipeHJhimktC64QZd87s15io= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cKVPiTR3; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cKVPiTR3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1370AC32782; Fri, 23 Aug 2024 00:01:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724371283; bh=46LiIuR6+JpkDUb8HzN7eFEsw9pn6pg7fd3b5GOs39k=; h=Date:Subject:From:To:Cc:In-Reply-To:References:From; b=cKVPiTR3cCtHvSuvbwbQdSCyBMUPLfqPOJVsvcd61JjuJrxHmJ4PDTpGsrdMd9UHs xWN0rVLpTKYp0CmGIq83nuoF1yg3PM+ccecIZ9TLdfokihAFJdtyMSVho5ev5tqNX5 IOPS6a2slR3jo3KVasEHPL0AHpRjSQKcQyvGL4iUC0qVGB9FPaGatMBAx6RaC9YNPf 392Na/i8ILteLo56rosW656F7cJBou0Zeflsms7BJncdzpSb3bzRhU4QfVtYFFvxew OtI2/OUryK5xaIHl3ucn58ywKEDKQKbdR6T65tHdGmwO4Q8/MzMV92UfmeW8WkpJZs mjr/KGP69aCLQ== Date: Thu, 22 Aug 2024 17:01:22 -0700 Subject: [PATCH 1/1] xfs: introduce new file range commit ioctls From: "Darrick J. Wong" To: djwong@kernel.org Cc: hch@lst.de, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Message-ID: <172437084278.57211.4355071581143024290.stgit@frogsfrogsfrogs> In-Reply-To: <172437084258.57211.13522832162579952916.stgit@frogsfrogsfrogs> References: <172437084258.57211.13522832162579952916.stgit@frogsfrogsfrogs> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Darrick J. Wong This patch introduces two more new ioctls to manage atomic updates to file contents -- XFS_IOC_START_COMMIT and XFS_IOC_COMMIT_RANGE. The commit mechanism here is exactly the same as what XFS_IOC_EXCHANGE_RANGE does, but with the additional requirement that file2 cannot have changed since some sampling point. The start-commit ioctl performs the sampling of file attributes. Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_fs.h | 26 +++++++++ fs/xfs/xfs_exchrange.c | 143 ++++++++++++++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_exchrange.h | 16 +++++ fs/xfs/xfs_ioctl.c | 4 + fs/xfs/xfs_trace.h | 57 +++++++++++++++++++ 5 files changed, 243 insertions(+), 3 deletions(-) diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h index 454b63ef72016..c85c8077fac39 100644 --- a/fs/xfs/libxfs/xfs_fs.h +++ b/fs/xfs/libxfs/xfs_fs.h @@ -825,6 +825,30 @@ struct xfs_exchange_range { __u64 flags; /* see XFS_EXCHANGE_RANGE_* below */ }; +/* + * Using the same definition of file2 as struct xfs_exchange_range, commit the + * contents of file1 into file2 if file2 has the same inode number, mtime, and + * ctime as the arguments provided to the call. The old contents of file2 will + * be moved to file1. + * + * Returns -EBUSY if there isn't an exact match for the file2 fields. + * + * Filesystems must be able to restart and complete the operation even after + * the system goes down. + */ +struct xfs_commit_range { + __s32 file1_fd; + __u32 pad; /* must be zeroes */ + __u64 file1_offset; /* file1 offset, bytes */ + __u64 file2_offset; /* file2 offset, bytes */ + __u64 length; /* bytes to exchange */ + + __u64 flags; /* see XFS_EXCHANGE_RANGE_* below */ + + /* opaque file2 metadata for freshness checks */ + __u64 file2_freshness[6]; +}; + /* * Exchange file data all the way to the ends of both files, and then exchange * the file sizes. This flag can be used to replace a file's contents with a @@ -997,6 +1021,8 @@ struct xfs_getparents_by_handle { #define XFS_IOC_BULKSTAT _IOR ('X', 127, struct xfs_bulkstat_req) #define XFS_IOC_INUMBERS _IOR ('X', 128, struct xfs_inumbers_req) #define XFS_IOC_EXCHANGE_RANGE _IOW ('X', 129, struct xfs_exchange_range) +#define XFS_IOC_START_COMMIT _IOR ('X', 130, struct xfs_commit_range) +#define XFS_IOC_COMMIT_RANGE _IOW ('X', 131, struct xfs_commit_range) /* XFS_IOC_GETFSUUID ---------- deprecated 140 */ diff --git a/fs/xfs/xfs_exchrange.c b/fs/xfs/xfs_exchrange.c index c8a655c92c92f..d0889190ab7ff 100644 --- a/fs/xfs/xfs_exchrange.c +++ b/fs/xfs/xfs_exchrange.c @@ -72,6 +72,34 @@ xfs_exchrange_estimate( return error; } +/* + * Check that file2's metadata agree with the snapshot that we took for the + * range commit request. + * + * This should be called after the filesystem has locked /all/ inode metadata + * against modification. + */ +STATIC int +xfs_exchrange_check_freshness( + const struct xfs_exchrange *fxr, + struct xfs_inode *ip2) +{ + struct inode *inode2 = VFS_I(ip2); + struct timespec64 ctime = inode_get_ctime(inode2); + struct timespec64 mtime = inode_get_mtime(inode2); + + trace_xfs_exchrange_freshness(fxr, ip2); + + /* Check that file2 hasn't otherwise been modified. */ + if (fxr->file2_ino != ip2->i_ino || + fxr->file2_gen != inode2->i_generation || + !timespec64_equal(&fxr->file2_ctime, &ctime) || + !timespec64_equal(&fxr->file2_mtime, &mtime)) + return -EBUSY; + + return 0; +} + #define QRETRY_IP1 (0x1) #define QRETRY_IP2 (0x2) @@ -607,6 +635,12 @@ xfs_exchrange_prep( if (error || fxr->length == 0) return error; + if (fxr->flags & __XFS_EXCHANGE_RANGE_CHECK_FRESH2) { + error = xfs_exchrange_check_freshness(fxr, ip2); + if (error) + return error; + } + /* Attach dquots to both inodes before changing block maps. */ error = xfs_qm_dqattach(ip2); if (error) @@ -719,7 +753,8 @@ xfs_exchange_range( if (fxr->file1->f_path.mnt != fxr->file2->f_path.mnt) return -EXDEV; - if (fxr->flags & ~XFS_EXCHANGE_RANGE_ALL_FLAGS) + if (fxr->flags & ~(XFS_EXCHANGE_RANGE_ALL_FLAGS | + __XFS_EXCHANGE_RANGE_CHECK_FRESH2)) return -EINVAL; /* Userspace requests only honored for regular files. */ @@ -802,3 +837,109 @@ xfs_ioc_exchange_range( fdput(file1); return error; } + +/* Opaque freshness blob for XFS_IOC_COMMIT_RANGE */ +struct xfs_commit_range_fresh { + xfs_fsid_t fsid; /* m_fixedfsid */ + __u64 file2_ino; /* inode number */ + __s64 file2_mtime; /* modification time */ + __s64 file2_ctime; /* change time */ + __s32 file2_mtime_nsec; /* mod time, nsec */ + __s32 file2_ctime_nsec; /* change time, nsec */ + __u32 file2_gen; /* inode generation */ + __u32 magic; /* zero */ +}; +#define XCR_FRESH_MAGIC 0x444F524B /* DORK */ + +/* Set up a commitrange operation by sampling file2's write-related attrs */ +long +xfs_ioc_start_commit( + struct file *file, + struct xfs_commit_range __user *argp) +{ + struct xfs_commit_range args = { }; + struct timespec64 ts; + struct xfs_commit_range_fresh *kern_f; + struct xfs_commit_range_fresh __user *user_f; + struct inode *inode2 = file_inode(file); + struct xfs_inode *ip2 = XFS_I(inode2); + const unsigned int lockflags = XFS_IOLOCK_SHARED | + XFS_MMAPLOCK_SHARED | + XFS_ILOCK_SHARED; + + BUILD_BUG_ON(sizeof(struct xfs_commit_range_fresh) != + sizeof(args.file2_freshness)); + + kern_f = (struct xfs_commit_range_fresh *)&args.file2_freshness; + + memcpy(&kern_f->fsid, ip2->i_mount->m_fixedfsid, sizeof(xfs_fsid_t)); + + xfs_ilock(ip2, lockflags); + ts = inode_get_ctime(inode2); + kern_f->file2_ctime = ts.tv_sec; + kern_f->file2_ctime_nsec = ts.tv_nsec; + ts = inode_get_mtime(inode2); + kern_f->file2_mtime = ts.tv_sec; + kern_f->file2_mtime_nsec = ts.tv_nsec; + kern_f->file2_ino = ip2->i_ino; + kern_f->file2_gen = inode2->i_generation; + kern_f->magic = XCR_FRESH_MAGIC; + xfs_iunlock(ip2, lockflags); + + user_f = (struct xfs_commit_range_fresh __user *)&argp->file2_freshness; + if (copy_to_user(user_f, kern_f, sizeof(*kern_f))) + return -EFAULT; + + return 0; +} + +/* + * Exchange file1 and file2 contents if file2 has not been written since the + * start commit operation. + */ +long +xfs_ioc_commit_range( + struct file *file, + struct xfs_commit_range __user *argp) +{ + struct xfs_exchrange fxr = { + .file2 = file, + }; + struct xfs_commit_range args; + struct xfs_commit_range_fresh *kern_f; + struct xfs_inode *ip2 = XFS_I(file_inode(file)); + struct xfs_mount *mp = ip2->i_mount; + struct fd file1; + int error; + + kern_f = (struct xfs_commit_range_fresh *)&args.file2_freshness; + + if (copy_from_user(&args, argp, sizeof(args))) + return -EFAULT; + if (args.flags & ~XFS_EXCHANGE_RANGE_ALL_FLAGS) + return -EINVAL; + if (kern_f->magic != XCR_FRESH_MAGIC) + return -EBUSY; + if (memcmp(&kern_f->fsid, mp->m_fixedfsid, sizeof(xfs_fsid_t))) + return -EBUSY; + + fxr.file1_offset = args.file1_offset; + fxr.file2_offset = args.file2_offset; + fxr.length = args.length; + fxr.flags = args.flags | __XFS_EXCHANGE_RANGE_CHECK_FRESH2; + fxr.file2_ino = kern_f->file2_ino; + fxr.file2_gen = kern_f->file2_gen; + fxr.file2_mtime.tv_sec = kern_f->file2_mtime; + fxr.file2_mtime.tv_nsec = kern_f->file2_mtime_nsec; + fxr.file2_ctime.tv_sec = kern_f->file2_ctime; + fxr.file2_ctime.tv_nsec = kern_f->file2_ctime_nsec; + + file1 = fdget(args.file1_fd); + if (!file1.file) + return -EBADF; + fxr.file1 = file1.file; + + error = xfs_exchange_range(&fxr); + fdput(file1); + return error; +} diff --git a/fs/xfs/xfs_exchrange.h b/fs/xfs/xfs_exchrange.h index 039abcca546e8..bc1298aba806b 100644 --- a/fs/xfs/xfs_exchrange.h +++ b/fs/xfs/xfs_exchrange.h @@ -10,8 +10,12 @@ #define __XFS_EXCHANGE_RANGE_UPD_CMTIME1 (1ULL << 63) #define __XFS_EXCHANGE_RANGE_UPD_CMTIME2 (1ULL << 62) +/* Freshness check required */ +#define __XFS_EXCHANGE_RANGE_CHECK_FRESH2 (1ULL << 61) + #define XFS_EXCHANGE_RANGE_PRIV_FLAGS (__XFS_EXCHANGE_RANGE_UPD_CMTIME1 | \ - __XFS_EXCHANGE_RANGE_UPD_CMTIME2) + __XFS_EXCHANGE_RANGE_UPD_CMTIME2 | \ + __XFS_EXCHANGE_RANGE_CHECK_FRESH2) struct xfs_exchrange { struct file *file1; @@ -22,10 +26,20 @@ struct xfs_exchrange { u64 length; u64 flags; /* XFS_EXCHANGE_RANGE flags */ + + /* file2 metadata for freshness checks */ + u64 file2_ino; + struct timespec64 file2_mtime; + struct timespec64 file2_ctime; + u32 file2_gen; }; long xfs_ioc_exchange_range(struct file *file, struct xfs_exchange_range __user *argp); +long xfs_ioc_start_commit(struct file *file, + struct xfs_commit_range __user *argp); +long xfs_ioc_commit_range(struct file *file, + struct xfs_commit_range __user *argp); struct xfs_exchmaps_req; diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 6b13666d4e963..90b3ee21e7fe6 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -1518,6 +1518,10 @@ xfs_file_ioctl( case XFS_IOC_EXCHANGE_RANGE: return xfs_ioc_exchange_range(filp, arg); + case XFS_IOC_START_COMMIT: + return xfs_ioc_start_commit(filp, arg); + case XFS_IOC_COMMIT_RANGE: + return xfs_ioc_commit_range(filp, arg); default: return -ENOTTY; diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index 180ce697305a9..4cf0fa71ba9ce 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -4926,7 +4926,8 @@ DEFINE_INODE_ERROR_EVENT(xfs_exchrange_error); { XFS_EXCHANGE_RANGE_DRY_RUN, "DRY_RUN" }, \ { XFS_EXCHANGE_RANGE_FILE1_WRITTEN, "F1_WRITTEN" }, \ { __XFS_EXCHANGE_RANGE_UPD_CMTIME1, "CMTIME1" }, \ - { __XFS_EXCHANGE_RANGE_UPD_CMTIME2, "CMTIME2" } + { __XFS_EXCHANGE_RANGE_UPD_CMTIME2, "CMTIME2" }, \ + { __XFS_EXCHANGE_RANGE_CHECK_FRESH2, "FRESH2" } /* file exchange-range tracepoint class */ DECLARE_EVENT_CLASS(xfs_exchrange_class, @@ -4986,6 +4987,60 @@ DEFINE_EXCHRANGE_EVENT(xfs_exchrange_prep); DEFINE_EXCHRANGE_EVENT(xfs_exchrange_flush); DEFINE_EXCHRANGE_EVENT(xfs_exchrange_mappings); +TRACE_EVENT(xfs_exchrange_freshness, + TP_PROTO(const struct xfs_exchrange *fxr, struct xfs_inode *ip2), + TP_ARGS(fxr, ip2), + TP_STRUCT__entry( + __field(dev_t, dev) + __field(xfs_ino_t, ip2_ino) + __field(long long, ip2_mtime) + __field(long long, ip2_ctime) + __field(int, ip2_mtime_nsec) + __field(int, ip2_ctime_nsec) + + __field(xfs_ino_t, file2_ino) + __field(long long, file2_mtime) + __field(long long, file2_ctime) + __field(int, file2_mtime_nsec) + __field(int, file2_ctime_nsec) + ), + TP_fast_assign( + struct timespec64 ts64; + struct inode *inode2 = VFS_I(ip2); + + __entry->dev = inode2->i_sb->s_dev; + __entry->ip2_ino = ip2->i_ino; + + ts64 = inode_get_ctime(inode2); + __entry->ip2_ctime = ts64.tv_sec; + __entry->ip2_ctime_nsec = ts64.tv_nsec; + + ts64 = inode_get_mtime(inode2); + __entry->ip2_mtime = ts64.tv_sec; + __entry->ip2_mtime_nsec = ts64.tv_nsec; + + __entry->file2_ino = fxr->file2_ino; + __entry->file2_mtime = fxr->file2_mtime.tv_sec; + __entry->file2_ctime = fxr->file2_ctime.tv_sec; + __entry->file2_mtime_nsec = fxr->file2_mtime.tv_nsec; + __entry->file2_ctime_nsec = fxr->file2_ctime.tv_nsec; + ), + TP_printk("dev %d:%d " + "ino 0x%llx mtime %lld:%d ctime %lld:%d -> " + "file 0x%llx mtime %lld:%d ctime %lld:%d", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->ip2_ino, + __entry->ip2_mtime, + __entry->ip2_mtime_nsec, + __entry->ip2_ctime, + __entry->ip2_ctime_nsec, + __entry->file2_ino, + __entry->file2_mtime, + __entry->file2_mtime_nsec, + __entry->file2_ctime, + __entry->file2_ctime_nsec) +); + TRACE_EVENT(xfs_exchmaps_overhead, TP_PROTO(struct xfs_mount *mp, unsigned long long bmbt_blocks, unsigned long long rmapbt_blocks),