From mboxrd@z Thu Jan 1 00:00:00 1970 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 602492773E9; Wed, 29 Oct 2025 00:52:00 +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=1761699120; cv=none; b=E8mJSySm4fbsaJNIzls7YIPlyzrYB84O2m+pQETLm1+wAEWOR7ehQs2eY39lGkNrKdplraKsoZCyJpDOyFcacPGuD+bSWnXuGiCjVryzOkOwh2IglYZgxy4g2iQN980PpfJ5PrzHR8deAKagpmeP1Y/oQiBTIy5Hf8AUNSY6xW0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761699120; c=relaxed/simple; bh=FpCfQG/VffBcfSwhsNzAUDrbMS88rAs1/P0QfcjwbKI=; h=Date:Subject:From:To:Cc:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=FDEYxCCooCx0DqzcpSwYTWVLsCMVlIJyZXbSQCdlT3YHTz/Nz4nGC+yKquJJ36Fp/yjCkSda4iqkSzHdzibvDsw2+fMSOKVLTRzIFiiJAK6WIf4C4N5RNlPBZa1L/dH4YIF96809P2lpmYy0uzlwAKLKMSH257sYvXkqKppdByw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XkQMMiZL; 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="XkQMMiZL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 37569C4CEE7; Wed, 29 Oct 2025 00:52:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761699120; bh=FpCfQG/VffBcfSwhsNzAUDrbMS88rAs1/P0QfcjwbKI=; h=Date:Subject:From:To:Cc:In-Reply-To:References:From; b=XkQMMiZLncB0AR4Tm3LIh7D/PlHw6hHLVPb8Wr+PUyxGcMdB5F2w7It2U0DJdym8X PpcOnNxXrSnaLgV8P4EAA4D+7vkUD/In/F60UY9Jkpv8N7/KSVyH2y9mLbXn+eWaI9 5Wzi2C36nNN/gjSmGzptP2klL+Cu4lC1vwHD7Y9Z0ofyeStfbs/aQO0TM4bcU3pwS2 Tthw0NAEt0+onzpHU6/FqAoxdfVSc2bI6q/bq1cDWe8p3UYarR5YKY1QW3j/5RxfjJ t5Wqd+LgfbQ8PCc13nE63EcqDwfVzUSbl1MEDCZGnmnrvNBz+xyJllvIDi+Jf1JD0L pxWUHjBPsqxEQ== Date: Tue, 28 Oct 2025 17:51:59 -0700 Subject: [PATCH 27/31] fuse: support atomic writes with iomap From: "Darrick J. Wong" To: djwong@kernel.org, miklos@szeredi.hu Cc: joannelkoong@gmail.com, bernd@bsbernd.com, neal@gompa.dev, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org Message-ID: <176169810937.1424854.17545235254390180266.stgit@frogsfrogsfrogs> In-Reply-To: <176169810144.1424854.11439355400009006946.stgit@frogsfrogsfrogs> References: <176169810144.1424854.11439355400009006946.stgit@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit From: Darrick J. Wong Enable untorn writes of up to a single fsblock, if iomap is enabled. Signed-off-by: "Darrick J. Wong" --- fs/fuse/fuse_i.h | 9 +++++++++ include/uapi/linux/fuse.h | 5 +++++ fs/fuse/file_iomap.c | 46 ++++++++++++++++++++++++++++++++++++++++++++- 3 files changed, 59 insertions(+), 1 deletion(-) diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index f6b6944fad553c..9ab1de8063c05e 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -266,6 +266,8 @@ enum { FUSE_I_EXCLUSIVE, /* Use iomap for this inode */ FUSE_I_IOMAP, + /* Enable untorn writes */ + FUSE_I_ATOMIC, }; struct fuse_conn; @@ -1768,6 +1770,13 @@ static inline bool fuse_inode_has_iomap(const struct inode *inode) return test_bit(FUSE_I_IOMAP, &fi->state); } +static inline bool fuse_inode_has_atomic(const struct inode *inode) +{ + const struct fuse_inode *fi = get_fuse_inode(inode); + + return test_bit(FUSE_I_ATOMIC, &fi->state); +} + int fuse_iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 length); loff_t fuse_iomap_lseek(struct file *file, loff_t offset, int whence); diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 838d925d2947e0..99ad2367d1dc20 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -246,6 +246,7 @@ * - add FUSE_ATTR_IOMAP to enable iomap for specific inodes * - add FUSE_IOMAP_CONFIG so the fuse server can configure more fs geometry * - add FUSE_NOTIFY_IOMAP_DEV_INVAL to invalidate iomap bdev ranges + * - add FUSE_ATTR_ATOMIC for single-fsblock atomic write support */ #ifndef _LINUX_FUSE_H @@ -600,10 +601,12 @@ struct fuse_file_lock { * FUSE_ATTR_SUBMOUNT: Object is a submount root * FUSE_ATTR_DAX: Enable DAX for this file in per inode DAX mode * FUSE_ATTR_IOMAP: Use iomap for this inode + * FUSE_ATTR_ATOMIC: Enable untorn writes */ #define FUSE_ATTR_SUBMOUNT (1 << 0) #define FUSE_ATTR_DAX (1 << 1) #define FUSE_ATTR_IOMAP (1 << 2) +#define FUSE_ATTR_ATOMIC (1 << 3) /** * Open flags @@ -1171,6 +1174,8 @@ struct fuse_backing_map { /* basic file I/O functionality through iomap */ #define FUSE_IOMAP_SUPPORT_FILEIO (1ULL << 0) +/* untorn writes through iomap */ +#define FUSE_IOMAP_SUPPORT_ATOMIC (1ULL << 1) struct fuse_iomap_support { uint64_t flags; uint64_t padding; diff --git a/fs/fuse/file_iomap.c b/fs/fuse/file_iomap.c index 06d1834e43f698..f4cb9dcde445ef 100644 --- a/fs/fuse/file_iomap.c +++ b/fs/fuse/file_iomap.c @@ -1099,6 +1099,20 @@ static inline void fuse_inode_clear_iomap(struct inode *inode) clear_bit(FUSE_I_IOMAP, &fi->state); } +static inline void fuse_inode_set_atomic(struct inode *inode) +{ + struct fuse_inode *fi = get_fuse_inode(inode); + + set_bit(FUSE_I_ATOMIC, &fi->state); +} + +static inline void fuse_inode_clear_atomic(struct inode *inode) +{ + struct fuse_inode *fi = get_fuse_inode(inode); + + clear_bit(FUSE_I_ATOMIC, &fi->state); +} + void fuse_iomap_init_nonreg_inode(struct inode *inode, unsigned attr_flags) { struct fuse_conn *conn = get_fuse_conn(inode); @@ -1122,6 +1136,8 @@ void fuse_iomap_init_reg_inode(struct inode *inode, unsigned attr_flags) if (conn->iomap && (attr_flags & FUSE_ATTR_IOMAP)) { set_bit(FUSE_I_EXCLUSIVE, &fi->state); fuse_inode_set_iomap(inode); + if (attr_flags & FUSE_ATTR_ATOMIC) + fuse_inode_set_atomic(inode); } trace_fuse_iomap_init_inode(inode); @@ -1134,6 +1150,8 @@ void fuse_iomap_evict_inode(struct inode *inode) trace_fuse_iomap_evict_inode(inode); + if (fuse_inode_has_atomic(inode)) + fuse_inode_clear_atomic(inode); if (fuse_inode_has_iomap(inode)) fuse_inode_clear_iomap(inode); if (conn->iomap && fuse_inode_is_exclusive(inode)) @@ -1214,6 +1232,8 @@ void fuse_iomap_open(struct inode *inode, struct file *file) ASSERT(fuse_inode_has_iomap(inode)); file->f_mode |= FMODE_NOWAIT | FMODE_CAN_ODIRECT; + if (fuse_inode_has_atomic(inode)) + file->f_mode |= FMODE_CAN_ATOMIC_WRITE; } enum fuse_ilock_type { @@ -1420,6 +1440,17 @@ fuse_iomap_write_checks( return kiocb_modified(iocb); } +static inline ssize_t fuse_iomap_atomic_write_valid(struct kiocb *iocb, + struct iov_iter *from) +{ + struct inode *inode = file_inode(iocb->ki_filp); + + if (iov_iter_count(from) != i_blocksize(inode)) + return -EINVAL; + + return generic_atomic_write_valid(iocb, from); +} + ssize_t fuse_iomap_direct_write(struct kiocb *iocb, struct iov_iter *from) { struct inode *inode = file_inode(iocb->ki_filp); @@ -1435,6 +1466,12 @@ ssize_t fuse_iomap_direct_write(struct kiocb *iocb, struct iov_iter *from) if (!count) return 0; + if (iocb->ki_flags & IOCB_ATOMIC) { + ret = fuse_iomap_atomic_write_valid(iocb, from); + if (ret) + return ret; + } + /* * Unaligned direct writes require zeroing of unwritten head and tail * blocks. Extending writes require zeroing of post-EOF tail blocks. @@ -1840,6 +1877,12 @@ ssize_t fuse_iomap_buffered_write(struct kiocb *iocb, struct iov_iter *from) if (!iov_iter_count(from)) return 0; + if (iocb->ki_flags & IOCB_ATOMIC) { + ret = fuse_iomap_atomic_write_valid(iocb, from); + if (ret) + return ret; + } + ret = fuse_iomap_ilock_iocb(iocb, EXCL); if (ret) return ret; @@ -2063,7 +2106,8 @@ int fuse_dev_ioctl_iomap_support(struct file *file, struct fuse_iomap_support ios = { }; if (fuse_iomap_enabled()) - ios.flags = FUSE_IOMAP_SUPPORT_FILEIO; + ios.flags = FUSE_IOMAP_SUPPORT_FILEIO | + FUSE_IOMAP_SUPPORT_ATOMIC; if (copy_to_user(argp, &ios, sizeof(ios))) return -EFAULT;