From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 2BA73353A8E; Tue, 11 Aug 2026 18:15:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786472119; cv=none; b=r7YwWwA/xogyxDO1bkAfgNfykYwAFa/3EWbgEEyqy5od3EbJgDu5NtIM/6fGXBmtNn33tntNWSb3RRvRY2Kw43gbWpEfkaVm6VBjsrvUJoYeamx255kDw1U3jbOhEHxwVK3MBp4LveCY7nwZ3r+UXXuAQBAF6dIzp4joqo91+wE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786472119; c=relaxed/simple; bh=v8a82oH3QarP6I8CBddMNieJTg8G5gwPz33bnEBPH1I=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=N2AXgjRyyLmCUPUw2MUGtK2BuwsSepqCp8jDd08I9yDiLKPnXQ8EuXfRPK6QnUT9pUzut+NgqqK2/3F9F0ChlkO1xpmOsKIzKN3Zb+vfj5rfF4zp62ccnzRv7rQR96dbABwg2O7LkkfzyJvEOT70smU6xFvyuw6KMihtw1ajRJ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=clno6O/Z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="clno6O/Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC7B61F00A3F; Tue, 11 Aug 2026 18:15:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786472113; bh=OXnftdUGJlC4cntuhv3BMGFqzvt2LM1k7YzvH1mHMHQ=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=clno6O/Z+k4l5ZF/Ksp86hxQf+9C5YOITr0V0kjfjiY1W+MQfFxB+dKzLGpYxQrXR 0/3xbBwQsCuzaVBjpIQnBjK6aCwiEcqLjmloZ2omYN25GiP35wEdCRJNRQBEX2rxAn CIG//bl8sJjwnEujClkW+Znhx0DX0qiI2jNpbiPzIieN46FjTHxHUH3m5ISPZmvxhG hG7Wq2musWv9d9WPF8fBDTRPElb/NlxJSGhjPRIohTZA6bnJBmY8e+775OLrfjDeBB wHQPbRH7vYwixT7pofifTEolgjqmHic1YSg2KS7sNsYPjh5dUwPmbxiqCtinFH17QF VocWZpwrJCN2w== From: Jeff Layton Date: Tue, 11 Aug 2026 14:14:59 -0400 Subject: [PATCH v3 6/6] btrfs: pre-allocate delayed dir index for non-overwrite rename Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260811-btrfs-enomem-v3-6-46a993fc3fe5@kernel.org> References: <20260811-btrfs-enomem-v3-0-46a993fc3fe5@kernel.org> In-Reply-To: <20260811-btrfs-enomem-v3-0-46a993fc3fe5@kernel.org> To: Chris Mason , David Sterba Cc: Qu Wenruo , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, Jeff Layton X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=7243; i=jlayton@kernel.org; h=from:subject:message-id; bh=v8a82oH3QarP6I8CBddMNieJTg8G5gwPz33bnEBPH1I=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBqe2arc2/r4Mvv0cPl8IiNahyaae65akZfL2ij1 aRlodrXNWeJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCantmqwAKCRAADmhBGVaC FQSJEADPqKwCteozx2yXw6skrgyxhq0OYVPRNSqsMwqDWopohroiFNAMKCOZflZVKjW2N6rq2+l +OkOIcOGqHWv8mb3L6aBh4/TIEzdZ4LPCD2dcn1xMhLDVrxMTJ+RMIf5gKxvBZFKOH5ovlBOr4c Ogl6RnpWzq+atJUb2Oh36nARK0gIlLzj7KgLDpbbvy6vI5tHtb38WLgPEvCcwpnSqcMLz7Yb0kr hF0nycQcD7pJ6kj7ZNLQ2jsY/Svb5RguAI2pySRSrUez9Gk35iiwcR4s1mNEuHY9RB9FoKwiffz 3mYs5fs38u/gNbv5o3I01B5xDflr0MsMXoZ4SnbwOm1HscO3EvsaEjVaHuNRIk6HCMypXo/eK49 nK6mpDtPE3vRuIVMvYZP+chygR3coPF5Q41/7AvUF6uDl6qejmGXByLs6/KJmwgxE2xxsKS3gSP qBznQ9jAxLy5hkCU/HmiP2fH7A3vFwmhybsTM1FXFZS3k7LcnqxWW+GZe2ZdTVejQRNOFBDdIQM gq55srO8tyzBQ7fOdSSpJKr91XWKAOz3n0Jcyq5YZtgPHx75itpqlDGJCKnAfHyPyMmCcQsBFXq oqYA2CEeemxavAC9ucnmJ9bwPTyxCXtqV4wKK6RucKHR2usPCl1SLuAje6OPwxEtY+6oEHQLAF4 2ob8xtdgyIIZNwQ== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 For rename() without an overwrite target, pre-allocate the delayed dir index before any btree modifications so that ENOMEM can be returned before the source is unlinked from the old directory. Add a prealloc parameter to btrfs_add_link() that allows callers to pass pre-allocated delayed dir index resources. When provided, btrfs_add_link() takes ownership: it either passes the prealloc to btrfs_insert_dir_item() (which commits or frees it), or frees it on early error. All existing callers pass NULL to preserve the current behavior. In btrfs_rename(), when new_inode is NULL (no overwrite), call btrfs_prealloc_delayed_dir_index() before the first btree modification and pass the result through to btrfs_add_link(). If the prealloc fails, -ENOMEM is returned before any btree state has changed. The local prealloc pointer is cleared once ownership passes to btrfs_add_link(), so the out_fail path only frees one we still own. For overwrite rename (new_inode != NULL), the transaction still aborts on ENOMEM since earlier unlink operations have already made irreversible btree modifications. Assisted-by: LLM Signed-off-by: Jeff Layton --- fs/btrfs/btrfs_inode.h | 4 +++- fs/btrfs/inode.c | 40 ++++++++++++++++++++++++++++++++-------- fs/btrfs/tree-log.c | 4 ++-- 3 files changed, 37 insertions(+), 11 deletions(-) diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 1082fa92c145..d4280f152027 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -525,9 +525,11 @@ int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index); int btrfs_unlink_inode(struct btrfs_trans_handle *trans, struct btrfs_inode *dir, struct btrfs_inode *inode, const struct fscrypt_str *name); +struct btrfs_dir_index_prealloc; int btrfs_add_link(struct btrfs_trans_handle *trans, struct btrfs_inode *parent_inode, struct btrfs_inode *inode, - const struct fscrypt_str *name, bool add_backref, u64 index); + const struct fscrypt_str *name, bool add_backref, u64 index, + struct btrfs_dir_index_prealloc *prealloc); int btrfs_delete_subvolume(struct btrfs_inode *dir, struct dentry *dentry); int btrfs_truncate_block(struct btrfs_inode *inode, u64 offset, u64 start, u64 end); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 5b79910d72f5..fd6d481f4d12 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -6862,7 +6862,7 @@ int btrfs_create_new_inode(struct btrfs_trans_handle *trans, } } else { ret = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), name, - false, BTRFS_I(inode)->dir_index); + false, BTRFS_I(inode)->dir_index, NULL); if (ret == -ENOMEM) { /* * Orphan the new inode instead of aborting. The inode @@ -6914,7 +6914,8 @@ int btrfs_create_new_inode(struct btrfs_trans_handle *trans, */ int btrfs_add_link(struct btrfs_trans_handle *trans, struct btrfs_inode *parent_inode, struct btrfs_inode *inode, - const struct fscrypt_str *name, bool add_backref, u64 index) + const struct fscrypt_str *name, bool add_backref, u64 index, + struct btrfs_dir_index_prealloc *prealloc) { int ret = 0; struct btrfs_key key; @@ -6940,11 +6941,13 @@ int btrfs_add_link(struct btrfs_trans_handle *trans, } /* Nothing to clean up yet */ - if (ret) + if (ret) { + btrfs_free_delayed_dir_index_prealloc(trans, prealloc); return ret; + } ret = btrfs_insert_dir_item(trans, name, parent_inode, &key, - btrfs_inode_type(inode), index, NULL); + btrfs_inode_type(inode), index, prealloc); if (ret == -EEXIST || ret == -EOVERFLOW || ret == -ENOMEM) goto fail_dir_item; else if (unlikely(ret)) { @@ -7098,7 +7101,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir, inode_set_ctime_current(inode); ret = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), - &fname.disk_name, true, index); + &fname.disk_name, true, index, NULL); if (ret) goto fail; @@ -8512,14 +8515,14 @@ static int btrfs_rename_exchange(struct inode *old_dir, } ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), - new_name, false, old_idx); + new_name, false, old_idx, NULL); if (unlikely(ret)) { btrfs_abort_transaction(trans, ret); goto out_fail; } ret = btrfs_add_link(trans, BTRFS_I(old_dir), BTRFS_I(new_inode), - old_name, false, new_idx); + old_name, false, new_idx, NULL); if (unlikely(ret)) { btrfs_abort_transaction(trans, ret); goto out_fail; @@ -8592,6 +8595,7 @@ static int btrfs_rename(struct mnt_idmap *idmap, struct inode *new_inode = d_inode(new_dentry); struct inode *old_inode = d_inode(old_dentry); struct btrfs_rename_ctx rename_ctx; + struct btrfs_dir_index_prealloc *prealloc = NULL; u64 index = 0; int ret; int ret2; @@ -8715,6 +8719,24 @@ static int btrfs_rename(struct mnt_idmap *idmap, if (ret) goto out_fail; + /* + * When not overwriting an existing entry, pre-allocate the delayed + * dir index now so that ENOMEM is returned before any btree + * modifications. For the overwrite case, too many btree changes + * have already happened by the time btrfs_add_link() is called. + */ + if (!new_inode) { + prealloc = btrfs_prealloc_delayed_dir_index( + BTRFS_I(new_dir), + new_fname.disk_name.name, + new_fname.disk_name.len); + if (IS_ERR(prealloc)) { + ret = PTR_ERR(prealloc); + prealloc = NULL; + goto out_fail; + } + } + BTRFS_I(old_inode)->dir_index = 0ULL; if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { /* force full log commit if subvolume involved. */ @@ -8810,7 +8832,8 @@ static int btrfs_rename(struct mnt_idmap *idmap, } ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), - &new_fname.disk_name, false, index); + &new_fname.disk_name, false, index, prealloc); + prealloc = NULL; if (unlikely(ret)) { btrfs_abort_transaction(trans, ret); goto out_fail; @@ -8835,6 +8858,7 @@ static int btrfs_rename(struct mnt_idmap *idmap, } } out_fail: + btrfs_free_delayed_dir_index_prealloc(trans, prealloc); if (logs_pinned) { btrfs_end_log_trans(root); btrfs_end_log_trans(dest); diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 7ba7b6098aa5..a043611f82e1 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -1683,7 +1683,7 @@ static noinline int add_inode_ref(struct walk_control *wc) } /* insert our name */ - ret = btrfs_add_link(trans, dir, inode, &name, false, ref_index); + ret = btrfs_add_link(trans, dir, inode, &name, false, ref_index, NULL); if (ret) { btrfs_abort_log_replay(wc, ret, "failed to add link for inode %llu in dir %llu ref_index %llu name %.*s root %llu", @@ -2031,7 +2031,7 @@ static noinline int insert_one_name(struct btrfs_trans_handle *trans, return PTR_ERR(dir); } - ret = btrfs_add_link(trans, dir, inode, name, true, index); + ret = btrfs_add_link(trans, dir, inode, name, true, index, NULL); /* FIXME, put inode into FIXUP list */ -- 2.55.0