From fe38d7df230b022e72014ef7aa799a4f2acfecf3 Mon Sep 17 00:00:00 2001 From: Maxim Patlasov Date: Thu, 10 Oct 2013 17:11:54 +0400 Subject: [PATCH] fuse: fuse_flush() should wait on writeback The aim of .flush fop is to hint file-system that flushing its state or caches or any other important data to reliable storage would be desirable now. fuse_flush() passes this hint by sending FUSE_FLUSH request to userspace. However, dirty pages and pages under writeback may be not visible to userspace yet if we won't ensure it explicitly. Signed-off-by: Maxim Patlasov Signed-off-by: Miklos Szeredi --- fs/fuse/file.c | 38 +++++++++++++++++++++++--------------- 1 file changed, 23 insertions(+), 15 deletions(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index d857530..d93f2a1 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -401,6 +401,21 @@ static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index) return 0; } +/* + * Wait for all pending writepages on the inode to finish. + * + * This is currently done by blocking further writes with FUSE_NOWRITE + * and waiting for all sent writes to complete. + * + * This must be called under i_mutex, otherwise the FUSE_NOWRITE usage + * could conflict with truncation. + */ +static void fuse_sync_writes(struct inode *inode) +{ + fuse_set_nowrite(inode); + fuse_release_nowrite(inode); +} + static int fuse_flush(struct file *file, fl_owner_t id) { struct inode *inode = file_inode(file); @@ -416,6 +431,14 @@ static int fuse_flush(struct file *file, fl_owner_t id) if (fc->no_flush) return 0; + err = filemap_write_and_wait(file->f_mapping); + if (err) + return err; + + mutex_lock(&inode->i_mutex); + fuse_sync_writes(inode); + mutex_unlock(&inode->i_mutex); + req = fuse_get_req_nofail_nopages(fc, file); memset(&inarg, 0, sizeof(inarg)); inarg.fh = ff->fh; @@ -436,21 +459,6 @@ static int fuse_flush(struct file *file, fl_owner_t id) return err; } -/* - * Wait for all pending writepages on the inode to finish. - * - * This is currently done by blocking further writes with FUSE_NOWRITE - * and waiting for all sent writes to complete. - * - * This must be called under i_mutex, otherwise the FUSE_NOWRITE usage - * could conflict with truncation. - */ -static void fuse_sync_writes(struct inode *inode) -{ - fuse_set_nowrite(inode); - fuse_release_nowrite(inode); -} - int fuse_fsync_common(struct file *file, loff_t start, loff_t end, int datasync, int isdir) { -- 2.7.4