From 5a132ffa76bdd48a2ecfe7ff543a406c883e42f4 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 15 Feb 2023 06:53:54 -0500 Subject: [PATCH] nfsd: allow reaping files still under writeback [ Upstream commit dcb779fcd4ed5984ad15991d574943d12a8693d1 ] On most filesystems, there is no reason to delay reaping an nfsd_file just because its underlying inode is still under writeback. nfsd just relies on client activity or the local flusher threads to do writeback. The main exception is NFS, which flushes all of its dirty data on last close. Add a new EXPORT_OP_FLUSH_ON_CLOSE flag to allow filesystems to signal that they do this, and only skip closing files under writeback on such filesystems. Also, remove a redundant NULL file pointer check in nfsd_file_check_writeback, and clean up nfs's export op flag definitions. Signed-off-by: Jeff Layton Acked-by: Anna Schumaker [ cel: adjusted to apply to v5.10.y ] Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- fs/nfs/export.c | 9 ++++++--- fs/nfsd/filecache.c | 12 +++++++++++- include/linux/exportfs.h | 1 + 3 files changed, 18 insertions(+), 4 deletions(-) diff --git a/fs/nfs/export.c b/fs/nfs/export.c index b347e3ce0cc8..993be63ab301 100644 --- a/fs/nfs/export.c +++ b/fs/nfs/export.c @@ -182,7 +182,10 @@ const struct export_operations nfs_export_ops = { .fh_to_dentry = nfs_fh_to_dentry, .get_parent = nfs_get_parent, .fetch_iversion = nfs_fetch_iversion, - .flags = EXPORT_OP_NOWCC|EXPORT_OP_NOSUBTREECHK| - EXPORT_OP_CLOSE_BEFORE_UNLINK|EXPORT_OP_REMOTE_FS| - EXPORT_OP_NOATOMIC_ATTR, + .flags = EXPORT_OP_NOWCC | + EXPORT_OP_NOSUBTREECHK | + EXPORT_OP_CLOSE_BEFORE_UNLINK | + EXPORT_OP_REMOTE_FS | + EXPORT_OP_NOATOMIC_ATTR | + EXPORT_OP_FLUSH_ON_CLOSE, }; diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 1d4c0387c419..080d79654785 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -401,13 +401,23 @@ nfsd_file_check_writeback(struct nfsd_file *nf) struct file *file = nf->nf_file; struct address_space *mapping; - if (!file || !(file->f_mode & FMODE_WRITE)) + /* File not open for write? */ + if (!(file->f_mode & FMODE_WRITE)) return false; + + /* + * Some filesystems (e.g. NFS) flush all dirty data on close. + * On others, there is no need to wait for writeback. + */ + if (!(file_inode(file)->i_sb->s_export_op->flags & EXPORT_OP_FLUSH_ON_CLOSE)) + return false; + mapping = file->f_mapping; return mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) || mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK); } + static bool nfsd_file_lru_add(struct nfsd_file *nf) { set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags); diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h index fe848901fcc3..218fc5c54e90 100644 --- a/include/linux/exportfs.h +++ b/include/linux/exportfs.h @@ -221,6 +221,7 @@ struct export_operations { #define EXPORT_OP_NOATOMIC_ATTR (0x10) /* Filesystem cannot supply atomic attribute updates */ +#define EXPORT_OP_FLUSH_ON_CLOSE (0x20) /* fs flushes file data on close */ unsigned long flags; };