From patchwork Tue Jun 15 09:17:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 460607 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, 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 3D276C48BE8 for ; Tue, 15 Jun 2021 09:18:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2081361434 for ; Tue, 15 Jun 2021 09:18:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231425AbhFOJU3 (ORCPT ); Tue, 15 Jun 2021 05:20:29 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:54442 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231243AbhFOJUV (ORCPT ); Tue, 15 Jun 2021 05:20:21 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 0C714219C4; Tue, 15 Jun 2021 09:18:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1623748695; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=t7igIsjuZi1JvEYkGCAYMapFEOcoZqyGHFLdZJ9amoQ=; b=wuSltVUtcbffkh57rA4M0xkAPc6hBBIQD7rqUxZeTvpXLa8DfBYKay4vZ+gDcd3w7PwCKR G/MM4NkcZvJ/MYlPrt5Nm2dQKwMTSwXaAzopBzG5WnNzjliPrwMbKXHhwnlAPSukU0wmnr DKjtXbcxh5pzihUaz7dlRoBHaHziGMk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1623748695; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=t7igIsjuZi1JvEYkGCAYMapFEOcoZqyGHFLdZJ9amoQ=; b=8BDoEOuUztARLzWeNKP7WRNHA+Jl7QZ0bqw8IEeBILnXjSHr9ivpspNG4F4cO+sksJYTxJ BJTqNMjxEf8y9EAw== Received: from quack2.suse.cz (unknown [10.100.200.198]) by relay2.suse.de (Postfix) with ESMTP id 67129A3B97; Tue, 15 Jun 2021 09:18:14 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 2424B1E125C; Tue, 15 Jun 2021 11:18:14 +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 , Christoph Hellwig , "Darrick J . Wong" , Hugh Dickins Subject: [PATCH 01/14] mm: Fix comments mentioning i_mutex Date: Tue, 15 Jun 2021 11:17:51 +0200 Message-Id: <20210615091814.28626-1-jack@suse.cz> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210615090844.6045-1-jack@suse.cz> References: <20210615090844.6045-1-jack@suse.cz> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=10823; h=from:subject; bh=mivglnSwswYFPkeVyv9F6vdXnrQ0F6cyovWhp1oQWu8=; b=owEBbQGS/pANAwAIAZydqgc/ZEDZAcsmYgBgyHBATgss+CqoCMoRtzmZ1tQiJoTcQ5Qb6Hbe2WI2 hbYp4XqJATMEAAEIAB0WIQSrWdEr1p4yirVVKBycnaoHP2RA2QUCYMhwQAAKCRCcnaoHP2RA2RMQB/ 9ol+MZ7HafDRq9/Fi7puPeZS2XRWjM8ZlEsZD22vXPb5t2ZfOIq4Mj+KdA7cjbPLzpBX4ILB6gc3Yd s0VCIzEq0uzDTJqXGYt+vnb2gRVgGoQNeJfDCnzhj3dmYGEflu0EP8jUtSLkntUtf2u/S+AFmO5vrT /ZeJv6v230aAAhaV6DEI4O8q2WakTECOPXhd+YbV1Ev9aJdFf6fChcn99uURiGXM9CMZeCEmfOTQok 2po5GDacNVP3Vwi5IuA9hSu3BD5ll6+d1XSxzQHnA4mvI44yln+6hVfPdKPtiHsU822MHs27ihOKQ8 iQVSm3NZd9XDF9MKCazcMe2oCixY5T X-Developer-Key: i=jack@suse.cz; a=openpgp; fpr=93C6099A142276A28BBE35D815BC833443038D8C Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org inode->i_mutex has been replaced with inode->i_rwsem long ago. Fix comments still mentioning i_mutex. Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Acked-by: Hugh Dickins Signed-off-by: Jan Kara --- mm/filemap.c | 10 +++++----- mm/madvise.c | 2 +- mm/memory-failure.c | 2 +- mm/rmap.c | 6 +++--- mm/shmem.c | 20 ++++++++++---------- mm/truncate.c | 8 ++++---- 6 files changed, 24 insertions(+), 24 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 66f7e9fdfbc4..ba1068a1837f 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -76,7 +76,7 @@ * ->swap_lock (exclusive_swap_page, others) * ->i_pages lock * - * ->i_mutex + * ->i_rwsem * ->i_mmap_rwsem (truncate->unmap_mapping_range) * * ->mmap_lock @@ -87,7 +87,7 @@ * ->mmap_lock * ->lock_page (access_process_vm) * - * ->i_mutex (generic_perform_write) + * ->i_rwsem (generic_perform_write) * ->mmap_lock (fault_in_pages_readable->do_page_fault) * * bdi->wb.list_lock @@ -3710,12 +3710,12 @@ EXPORT_SYMBOL(generic_perform_write); * modification times and calls proper subroutines depending on whether we * do direct IO or a standard buffered write. * - * It expects i_mutex to be grabbed unless we work on a block device or similar + * It expects i_rwsem to be grabbed unless we work on a block device or similar * object which does not need locking at all. * * This function does *not* take care of syncing data in case of O_SYNC write. * A caller has to handle it. This is mainly due to the fact that we want to - * avoid syncing under i_mutex. + * avoid syncing under i_rwsem. * * Return: * * number of bytes written, even for truncated writes @@ -3803,7 +3803,7 @@ EXPORT_SYMBOL(__generic_file_write_iter); * * This is a wrapper around __generic_file_write_iter() to be used by most * filesystems. It takes care of syncing the file in case of O_SYNC file - * and acquires i_mutex as needed. + * and acquires i_rwsem as needed. * Return: * * negative error code if no data has been written at all of * vfs_fsync_range() failed for a synchronous write diff --git a/mm/madvise.c b/mm/madvise.c index 63e489e5bfdb..a0137706b92a 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -853,7 +853,7 @@ static long madvise_remove(struct vm_area_struct *vma, + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); /* - * Filesystem's fallocate may need to take i_mutex. We need to + * Filesystem's fallocate may need to take i_rwsem. We need to * explicitly grab a reference because the vma (and hence the * vma's reference to the file) can go away as soon as we drop * mmap_lock. diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 85ad98c00fd9..9dcc9bcea731 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -704,7 +704,7 @@ static int me_pagecache_clean(struct page *p, unsigned long pfn) /* * Truncation is a bit tricky. Enable it per file system for now. * - * Open: to take i_mutex or not for this? Right now we don't. + * Open: to take i_rwsem or not for this? Right now we don't. */ return truncate_error_page(p, pfn, mapping); } diff --git a/mm/rmap.c b/mm/rmap.c index 693a610e181d..a35cbbbded0d 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -20,9 +20,9 @@ /* * Lock ordering in mm: * - * inode->i_mutex (while writing or truncating, not reading or faulting) + * inode->i_rwsem (while writing or truncating, not reading or faulting) * mm->mmap_lock - * page->flags PG_locked (lock_page) * (see huegtlbfs below) + * page->flags PG_locked (lock_page) * (see hugetlbfs below) * hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share) * mapping->i_mmap_rwsem * hugetlb_fault_mutex (hugetlbfs specific page fault mutex) @@ -41,7 +41,7 @@ * in arch-dependent flush_dcache_mmap_lock, * within bdi.wb->list_lock in __sync_single_inode) * - * anon_vma->rwsem,mapping->i_mutex (memory_failure, collect_procs_anon) + * anon_vma->rwsem,mapping->i_mmap_rwsem (memory_failure, collect_procs_anon) * ->tasklist_lock * pte map lock * diff --git a/mm/shmem.c b/mm/shmem.c index 5d46611cba8d..0a26c64f6a2e 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -96,7 +96,7 @@ static struct vfsmount *shm_mnt; /* * shmem_fallocate communicates with shmem_fault or shmem_writepage via - * inode->i_private (with i_mutex making sure that it has only one user at + * inode->i_private (with i_rwsem making sure that it has only one user at * a time): we would prefer not to enlarge the shmem inode just for that. */ struct shmem_falloc { @@ -774,7 +774,7 @@ static int shmem_free_swap(struct address_space *mapping, * Determine (in bytes) how many of the shmem object's pages mapped by the * given offsets are swapped out. * - * This is safe to call without i_mutex or the i_pages lock thanks to RCU, + * This is safe to call without i_rwsem or the i_pages lock thanks to RCU, * as long as the inode doesn't go away and racy results are not a problem. */ unsigned long shmem_partial_swap_usage(struct address_space *mapping, @@ -806,7 +806,7 @@ unsigned long shmem_partial_swap_usage(struct address_space *mapping, * Determine (in bytes) how many of the shmem object's pages mapped by the * given vma is swapped out. * - * This is safe to call without i_mutex or the i_pages lock thanks to RCU, + * This is safe to call without i_rwsem or the i_pages lock thanks to RCU, * as long as the inode doesn't go away and racy results are not a problem. */ unsigned long shmem_swap_usage(struct vm_area_struct *vma) @@ -1069,7 +1069,7 @@ static int shmem_setattr(struct user_namespace *mnt_userns, loff_t oldsize = inode->i_size; loff_t newsize = attr->ia_size; - /* protected by i_mutex */ + /* protected by i_rwsem */ if ((newsize < oldsize && (info->seals & F_SEAL_SHRINK)) || (newsize > oldsize && (info->seals & F_SEAL_GROW))) return -EPERM; @@ -2049,7 +2049,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) /* * Trinity finds that probing a hole which tmpfs is punching can * prevent the hole-punch from ever completing: which in turn - * locks writers out with its hold on i_mutex. So refrain from + * locks writers out with its hold on i_rwsem. So refrain from * faulting pages into the hole while it's being punched. Although * shmem_undo_range() does remove the additions, it may be unable to * keep up, as each new page needs its own unmap_mapping_range() call, @@ -2060,7 +2060,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) * we just need to make racing faults a rare case. * * The implementation below would be much simpler if we just used a - * standard mutex or completion: but we cannot take i_mutex in fault, + * standard mutex or completion: but we cannot take i_rwsem in fault, * and bloating every shmem inode for this unlikely case would be sad. */ if (unlikely(inode->i_private)) { @@ -2514,7 +2514,7 @@ shmem_write_begin(struct file *file, struct address_space *mapping, struct shmem_inode_info *info = SHMEM_I(inode); pgoff_t index = pos >> PAGE_SHIFT; - /* i_mutex is held by caller */ + /* i_rwsem is held by caller */ if (unlikely(info->seals & (F_SEAL_GROW | F_SEAL_WRITE | F_SEAL_FUTURE_WRITE))) { if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) @@ -2614,7 +2614,7 @@ static ssize_t shmem_file_read_iter(struct kiocb *iocb, struct iov_iter *to) /* * We must evaluate after, since reads (unlike writes) - * are called without i_mutex protection against truncate + * are called without i_rwsem protection against truncate */ nr = PAGE_SIZE; i_size = i_size_read(inode); @@ -2684,7 +2684,7 @@ static loff_t shmem_file_llseek(struct file *file, loff_t offset, int whence) return -ENXIO; inode_lock(inode); - /* We're holding i_mutex so we can access i_size directly */ + /* We're holding i_rwsem so we can access i_size directly */ offset = mapping_seek_hole_data(mapping, offset, inode->i_size, whence); if (offset >= 0) offset = vfs_setpos(file, offset, MAX_LFS_FILESIZE); @@ -2713,7 +2713,7 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset, loff_t unmap_end = round_down(offset + len, PAGE_SIZE) - 1; DECLARE_WAIT_QUEUE_HEAD_ONSTACK(shmem_falloc_waitq); - /* protected by i_mutex */ + /* protected by i_rwsem */ if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) { error = -EPERM; goto out; diff --git a/mm/truncate.c b/mm/truncate.c index 95af244b112a..57a618c4a0d6 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -415,7 +415,7 @@ EXPORT_SYMBOL(truncate_inode_pages_range); * @mapping: mapping to truncate * @lstart: offset from which to truncate * - * Called under (and serialised by) inode->i_mutex. + * Called under (and serialised by) inode->i_rwsem. * * Note: When this function returns, there can be a page in the process of * deletion (inside __delete_from_page_cache()) in the specified range. Thus @@ -432,7 +432,7 @@ EXPORT_SYMBOL(truncate_inode_pages); * truncate_inode_pages_final - truncate *all* pages before inode dies * @mapping: mapping to truncate * - * Called under (and serialized by) inode->i_mutex. + * Called under (and serialized by) inode->i_rwsem. * * Filesystems have to use this in the .evict_inode path to inform the * VM that this is the final truncate and the inode is going away. @@ -753,7 +753,7 @@ EXPORT_SYMBOL(truncate_pagecache); * setattr function when ATTR_SIZE is passed in. * * Must be called with a lock serializing truncates and writes (generally - * i_mutex but e.g. xfs uses a different lock) and before all filesystem + * i_rwsem but e.g. xfs uses a different lock) and before all filesystem * specific block truncation has been performed. */ void truncate_setsize(struct inode *inode, loff_t newsize) @@ -782,7 +782,7 @@ EXPORT_SYMBOL(truncate_setsize); * * The function must be called after i_size is updated so that page fault * coming after we unlock the page will already see the new i_size. - * The function must be called while we still hold i_mutex - this not only + * The function must be called while we still hold i_rwsem - this not only * makes sure i_size is stable but also that userspace cannot observe new * i_size value before we are prepared to store mmap writes at new inode size. */