From patchwork Wed May 12 13:46:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 12253671 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 01831C2B9F7 for ; Wed, 12 May 2021 13:46:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BE2A6613E6 for ; Wed, 12 May 2021 13:46:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231295AbhELNrr (ORCPT ); Wed, 12 May 2021 09:47:47 -0400 Received: from mx2.suse.de ([195.135.220.15]:41532 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231143AbhELNrn (ORCPT ); Wed, 12 May 2021 09:47:43 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 5DA2AB1B5; Wed, 12 May 2021 13:46:32 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id E3FB41E0FC4; Wed, 12 May 2021 15:46:31 +0200 (CEST) From: Jan Kara To: Cc: Christoph Hellwig , Dave Chinner , ceph-devel@vger.kernel.org, Chao Yu , Damien Le Moal , "Darrick J. Wong" , Jaegeuk Kim , Jeff Layton , Johannes Thumshirn , linux-cifs@vger.kernel.org, , linux-f2fs-devel@lists.sourceforge.net, , , Miklos Szeredi , Steve French , Ted Tso , Matthew Wilcox , Jan Kara Subject: [PATCH 04/11] ext4: Convert to use mapping->invalidate_lock Date: Wed, 12 May 2021 15:46:12 +0200 Message-Id: <20210512134631.4053-4-jack@suse.cz> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210512101639.22278-1-jack@suse.cz> References: <20210512101639.22278-1-jack@suse.cz> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org Convert ext4 to use mapping->invalidate_lock instead of its private EXT4_I(inode)->i_mmap_sem. This is mostly search-and-replace. By this conversion we fix a long standing race between hole punching and read(2) / readahead(2) paths that can lead to stale page cache contents. CC: CC: Ted Tso Signed-off-by: Jan Kara --- fs/ext4/ext4.h | 10 ---------- fs/ext4/extents.c | 25 +++++++++++++----------- fs/ext4/file.c | 13 +++++++------ fs/ext4/inode.c | 47 +++++++++++++++++----------------------------- fs/ext4/ioctl.c | 4 ++-- fs/ext4/super.c | 13 +++++-------- fs/ext4/truncate.h | 8 +++++--- 7 files changed, 50 insertions(+), 70 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 37002663d521..ed64b4b217a1 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1077,15 +1077,6 @@ struct ext4_inode_info { * by other means, so we have i_data_sem. */ struct rw_semaphore i_data_sem; - /* - * i_mmap_sem is for serializing page faults with truncate / punch hole - * operations. We have to make sure that new page cannot be faulted in - * a section of the inode that is being punched. We cannot easily use - * i_data_sem for this since we need protection for the whole punch - * operation and i_data_sem ranks below transaction start so we have - * to occasionally drop it. - */ - struct rw_semaphore i_mmap_sem; struct inode vfs_inode; struct jbd2_inode *jinode; @@ -2962,7 +2953,6 @@ extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks); extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode, loff_t lstart, loff_t lend); extern vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf); -extern vm_fault_t ext4_filemap_fault(struct vm_fault *vmf); extern qsize_t *ext4_get_reserved_space(struct inode *inode); extern int ext4_get_projid(struct inode *inode, kprojid_t *projid); extern void ext4_da_release_space(struct inode *inode, int to_free); diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 77c84d6f1af6..8bb6b84c8a84 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4467,6 +4467,7 @@ static long ext4_zero_range(struct file *file, loff_t offset, loff_t len, int mode) { struct inode *inode = file_inode(file); + struct address_space *mapping = file->f_mapping; handle_t *handle = NULL; unsigned int max_blocks; loff_t new_size = 0; @@ -4553,17 +4554,17 @@ static long ext4_zero_range(struct file *file, loff_t offset, * Prevent page faults from reinstantiating pages we have * released from page cache. */ - down_write(&EXT4_I(inode)->i_mmap_sem); + down_write(&mapping->invalidate_lock); ret = ext4_break_layouts(inode); if (ret) { - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&mapping->invalidate_lock); goto out_mutex; } ret = ext4_update_disksize_before_punch(inode, offset, len); if (ret) { - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&mapping->invalidate_lock); goto out_mutex; } /* Now release the pages and zero block aligned part of pages */ @@ -4572,7 +4573,7 @@ static long ext4_zero_range(struct file *file, loff_t offset, ret = ext4_alloc_file_blocks(file, lblk, max_blocks, new_size, flags); - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&mapping->invalidate_lock); if (ret) goto out_mutex; } @@ -5214,6 +5215,7 @@ ext4_ext_shift_extents(struct inode *inode, handle_t *handle, static int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) { struct super_block *sb = inode->i_sb; + struct address_space *mapping = inode->i_mapping; ext4_lblk_t punch_start, punch_stop; handle_t *handle; unsigned int credits; @@ -5267,7 +5269,7 @@ static int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) * Prevent page faults from reinstantiating pages we have released from * page cache. */ - down_write(&EXT4_I(inode)->i_mmap_sem); + down_write(&mapping->invalidate_lock); ret = ext4_break_layouts(inode); if (ret) @@ -5282,15 +5284,15 @@ static int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) * Write tail of the last page before removed range since it will get * removed from the page cache below. */ - ret = filemap_write_and_wait_range(inode->i_mapping, ioffset, offset); + ret = filemap_write_and_wait_range(mapping, ioffset, offset); if (ret) goto out_mmap; /* * Write data that will be shifted to preserve them when discarding * page cache below. We are also protected from pages becoming dirty - * by i_mmap_sem. + * by i_rwsem and invalidate_lock. */ - ret = filemap_write_and_wait_range(inode->i_mapping, offset + len, + ret = filemap_write_and_wait_range(mapping, offset + len, LLONG_MAX); if (ret) goto out_mmap; @@ -5343,7 +5345,7 @@ static int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) ext4_journal_stop(handle); ext4_fc_stop_ineligible(sb); out_mmap: - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&mapping->invalidate_lock); out_mutex: inode_unlock(inode); return ret; @@ -5360,6 +5362,7 @@ static int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) static int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len) { struct super_block *sb = inode->i_sb; + struct address_space *mapping = inode->i_mapping; handle_t *handle; struct ext4_ext_path *path; struct ext4_extent *extent; @@ -5418,7 +5421,7 @@ static int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len) * Prevent page faults from reinstantiating pages we have released from * page cache. */ - down_write(&EXT4_I(inode)->i_mmap_sem); + down_write(&mapping->invalidate_lock); ret = ext4_break_layouts(inode); if (ret) @@ -5519,7 +5522,7 @@ static int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len) ext4_journal_stop(handle); ext4_fc_stop_ineligible(sb); out_mmap: - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&mapping->invalidate_lock); out_mutex: inode_unlock(inode); return ret; diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 816dedcbd541..f5993d3bd7b2 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -704,22 +704,23 @@ static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf, */ bool write = (vmf->flags & FAULT_FLAG_WRITE) && (vmf->vma->vm_flags & VM_SHARED); + struct address_space *mapping = vmf->vma->vm_file->f_mapping; pfn_t pfn; if (write) { sb_start_pagefault(sb); file_update_time(vmf->vma->vm_file); - down_read(&EXT4_I(inode)->i_mmap_sem); + down_read(&mapping->invalidate_lock); retry: handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE, EXT4_DATA_TRANS_BLOCKS(sb)); if (IS_ERR(handle)) { - up_read(&EXT4_I(inode)->i_mmap_sem); + up_read(&mapping->invalidate_lock); sb_end_pagefault(sb); return VM_FAULT_SIGBUS; } } else { - down_read(&EXT4_I(inode)->i_mmap_sem); + down_read(&mapping->invalidate_lock); } result = dax_iomap_fault(vmf, pe_size, &pfn, &error, &ext4_iomap_ops); if (write) { @@ -731,10 +732,10 @@ static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf, /* Handling synchronous page fault? */ if (result & VM_FAULT_NEEDDSYNC) result = dax_finish_sync_fault(vmf, pe_size, pfn); - up_read(&EXT4_I(inode)->i_mmap_sem); + up_read(&mapping->invalidate_lock); sb_end_pagefault(sb); } else { - up_read(&EXT4_I(inode)->i_mmap_sem); + up_read(&mapping->invalidate_lock); } return result; @@ -756,7 +757,7 @@ static const struct vm_operations_struct ext4_dax_vm_ops = { #endif static const struct vm_operations_struct ext4_file_vm_ops = { - .fault = ext4_filemap_fault, + .fault = filemap_fault, .map_pages = filemap_map_pages, .page_mkwrite = ext4_page_mkwrite, }; diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index fe6045a46599..9db1bba28271 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3950,20 +3950,19 @@ int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset, return ret; } -static void ext4_wait_dax_page(struct ext4_inode_info *ei) +static void ext4_wait_dax_page(struct inode *inode) { - up_write(&ei->i_mmap_sem); + up_write(&inode->i_mapping->invalidate_lock); schedule(); - down_write(&ei->i_mmap_sem); + down_write(&inode->i_mapping->invalidate_lock); } int ext4_break_layouts(struct inode *inode) { - struct ext4_inode_info *ei = EXT4_I(inode); struct page *page; int error; - if (WARN_ON_ONCE(!rwsem_is_locked(&ei->i_mmap_sem))) + if (WARN_ON_ONCE(!rwsem_is_locked(&inode->i_mapping->invalidate_lock))) return -EINVAL; do { @@ -3974,7 +3973,7 @@ int ext4_break_layouts(struct inode *inode) error = ___wait_var_event(&page->_refcount, atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE, 0, 0, - ext4_wait_dax_page(ei)); + ext4_wait_dax_page(inode)); } while (error == 0); return error; @@ -4005,9 +4004,9 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA); if (ext4_has_inline_data(inode)) { - down_write(&EXT4_I(inode)->i_mmap_sem); + down_write(&mapping->invalidate_lock); ret = ext4_convert_inline_data(inode); - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&mapping->invalidate_lock); if (ret) return ret; } @@ -4058,7 +4057,7 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) * Prevent page faults from reinstantiating pages we have released from * page cache. */ - down_write(&EXT4_I(inode)->i_mmap_sem); + down_write(&mapping->invalidate_lock); ret = ext4_break_layouts(inode); if (ret) @@ -4131,7 +4130,7 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) out_stop: ext4_journal_stop(handle); out_dio: - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&mapping->invalidate_lock); out_mutex: inode_unlock(inode); return ret; @@ -5426,11 +5425,11 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, inode_dio_wait(inode); } - down_write(&EXT4_I(inode)->i_mmap_sem); + down_write(&inode->i_mapping->invalidate_lock); rc = ext4_break_layouts(inode); if (rc) { - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&inode->i_mapping->invalidate_lock); goto err_out; } @@ -5506,7 +5505,7 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, error = rc; } out_mmap_sem: - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&inode->i_mapping->invalidate_lock); } if (!error) { @@ -5983,10 +5982,10 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val) * data (and journalled aops don't know how to handle these cases). */ if (val) { - down_write(&EXT4_I(inode)->i_mmap_sem); + down_write(&inode->i_mapping->invalidate_lock); err = filemap_write_and_wait(inode->i_mapping); if (err < 0) { - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&inode->i_mapping->invalidate_lock); return err; } } @@ -6019,7 +6018,7 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val) percpu_up_write(&sbi->s_writepages_rwsem); if (val) - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&inode->i_mapping->invalidate_lock); /* Finally we can mark the inode as dirty. */ @@ -6063,7 +6062,7 @@ vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf) sb_start_pagefault(inode->i_sb); file_update_time(vma->vm_file); - down_read(&EXT4_I(inode)->i_mmap_sem); + down_read(&mapping->invalidate_lock); err = ext4_convert_inline_data(inode); if (err) @@ -6176,7 +6175,7 @@ vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf) out_ret: ret = block_page_mkwrite_return(err); out: - up_read(&EXT4_I(inode)->i_mmap_sem); + up_read(&mapping->invalidate_lock); sb_end_pagefault(inode->i_sb); return ret; out_error: @@ -6184,15 +6183,3 @@ vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf) ext4_journal_stop(handle); goto out; } - -vm_fault_t ext4_filemap_fault(struct vm_fault *vmf) -{ - struct inode *inode = file_inode(vmf->vma->vm_file); - vm_fault_t ret; - - down_read(&EXT4_I(inode)->i_mmap_sem); - ret = filemap_fault(vmf); - up_read(&EXT4_I(inode)->i_mmap_sem); - - return ret; -} diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 31627f7dc5cd..cedc604726c2 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -148,7 +148,7 @@ static long swap_inode_boot_loader(struct super_block *sb, goto journal_err_out; } - down_write(&EXT4_I(inode)->i_mmap_sem); + down_write(&inode->i_mapping->invalidate_lock); err = filemap_write_and_wait(inode->i_mapping); if (err) goto err_out; @@ -256,7 +256,7 @@ static long swap_inode_boot_loader(struct super_block *sb, ext4_double_up_write_data_sem(inode, inode_bl); err_out: - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&inode->i_mapping->invalidate_lock); journal_err_out: unlock_two_nondirectories(inode, inode_bl); iput(inode_bl); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 7dc94f3e18e6..966fd5ca48e0 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -90,12 +90,9 @@ static struct inode *ext4_get_journal_inode(struct super_block *sb, /* * Lock ordering * - * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and - * i_mmap_rwsem (inode->i_mmap_rwsem)! - * * page fault path: - * mmap_lock -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start -> - * page lock -> i_data_sem (rw) + * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start + * -> page lock -> i_data_sem (rw) * * buffered write path: * sb_start_write -> i_mutex -> mmap_lock @@ -103,8 +100,9 @@ static struct inode *ext4_get_journal_inode(struct super_block *sb, * i_data_sem (rw) * * truncate: - * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock - * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start -> + * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) -> + * page lock + * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start -> * i_data_sem (rw) * * direct IO: @@ -1350,7 +1348,6 @@ static void init_once(void *foo) INIT_LIST_HEAD(&ei->i_orphan); init_rwsem(&ei->xattr_sem); init_rwsem(&ei->i_data_sem); - init_rwsem(&ei->i_mmap_sem); inode_init_once(&ei->vfs_inode); ext4_fc_init_inode(&ei->vfs_inode); } diff --git a/fs/ext4/truncate.h b/fs/ext4/truncate.h index bcbe3668c1d4..b7242e08c9dd 100644 --- a/fs/ext4/truncate.h +++ b/fs/ext4/truncate.h @@ -11,14 +11,16 @@ */ static inline void ext4_truncate_failed_write(struct inode *inode) { + struct address_space *mapping = inode->i_mapping; + /* * We don't need to call ext4_break_layouts() because the blocks we * are truncating were never visible to userspace. */ - down_write(&EXT4_I(inode)->i_mmap_sem); - truncate_inode_pages(inode->i_mapping, inode->i_size); + down_write(&mapping->invalidate_lock); + truncate_inode_pages(mapping, inode->i_size); ext4_truncate(inode); - up_write(&EXT4_I(inode)->i_mmap_sem); + up_write(&mapping->invalidate_lock); } /*