From: Jeff Layton Subject: [PATCH v4 24/27][RFC] nfs: convert to new errseq_t based error tracking for writeback errors Date: Tue, 9 May 2017 11:49:27 -0400 Message-ID: <20170509154930.29524-25-jlayton@redhat.com> References: <20170509154930.29524-1-jlayton@redhat.com> Cc: axboe@kernel.dk, tytso@mit.edu, mawilcox@microsoft.com, neilb@suse.de, corbet@lwn.net, josef@toxicpanda.com, dhowells@redhat.com, clm@fb.com, bo.li.liu@oracle.com, viro@zeniv.linux.org.uk, jack@suse.com, akpm@linux-foundation.org, ross.zwisler@linux.intel.com, hubcap@omnibond.com To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-mm@kvack.org, jfs-discussion@lists.sourceforge.net, linux-xfs@vger.kernel.org, cluster-devel@redhat.com, linux-f2fs-devel@lists.sourceforge.net, v9fs-developer@lists.sourceforge.net, linux-nilfs@vger.kernel.org, linux-block@vger.kernel.org Return-path: In-Reply-To: <20170509154930.29524-1-jlayton@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cluster-devel-bounces@redhat.com Errors-To: cluster-devel-bounces@redhat.com List-Id: linux-ext4.vger.kernel.org Drop the ERROR_WRITE flag and convert the error field in the context to a errseq_t. Add a new wb_err_cursor to track the reporting of the errseq_t. In principle, we could use the f_wb_err field in struct file for that, but that's problematic with the stock reporting in call_fsync. Signed-off-by: Jeff Layton --- fs/nfs/file.c | 19 +++++++++++-------- fs/nfs/inode.c | 5 +++-- fs/nfs/write.c | 2 +- include/linux/nfs_fs.h | 3 ++- 4 files changed, 17 insertions(+), 12 deletions(-) I did this on a lark to see how it would be, but I don't think this is really better than what's there already. There may be a better way to provide the right semantics without using an errseq_t here. diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 668213984d68..fd4d2b381d4b 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -212,21 +212,24 @@ nfs_file_fsync_commit(struct file *file, loff_t start, loff_t end, int datasync) { struct nfs_open_context *ctx = nfs_file_open_context(file); struct inode *inode = file_inode(file); - int have_error, do_resend, status; - int ret = 0; + int do_resend, status; + int ret; dprintk("NFS: fsync file(%pD2) datasync %d\n", file, datasync); nfs_inc_stats(inode, NFSIOS_VFSFSYNC); do_resend = test_and_clear_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags); - have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); + clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); status = nfs_commit_inode(inode, FLUSH_SYNC); - have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); - if (have_error) { - ret = xchg(&ctx->error, 0); - if (ret) - goto out; + ret = errseq_check(&ctx->wb_err, READ_ONCE(ctx->wb_err_cursor)); + if (ret) { + /* Use f_lock to serialize changes to wb_err_cursor */ + spin_lock(&file->f_lock); + ret = errseq_check_and_advance(&ctx->wb_err, &ctx->wb_err_cursor); + spin_unlock(&file->f_lock); } + if (ret) + goto out; if (status < 0) { ret = status; goto out; diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index f489a5a71bd5..ca85f6b39e3b 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -869,7 +869,8 @@ struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, ctx->state = NULL; ctx->mode = f_mode; ctx->flags = 0; - ctx->error = 0; + ctx->wb_err = 0; + ctx->wb_err_cursor = 0; ctx->flock_owner = (fl_owner_t)filp; nfs_init_lock_context(&ctx->lock_context); ctx->lock_context.open_context = ctx; @@ -978,7 +979,7 @@ void nfs_file_clear_open_context(struct file *filp) * We fatal error on write before. Try to writeback * every page again. */ - if (ctx->error < 0) + if (errseq_check(&ctx->wb_err, ctx->wb_err_cursor)) invalidate_inode_pages2(inode->i_mapping); filp->private_data = NULL; spin_lock(&inode->i_lock); diff --git a/fs/nfs/write.c b/fs/nfs/write.c index abb2c8a3be42..95a5b4ac6714 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -94,7 +94,7 @@ static void nfs_writehdr_free(struct nfs_pgio_header *hdr) static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error) { - ctx->error = error; + errseq_set(&ctx->wb_err, error); smp_wmb(); set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); } diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index 287f34161086..336adf1a38f7 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -76,7 +76,8 @@ struct nfs_open_context { #define NFS_CONTEXT_ERROR_WRITE (0) #define NFS_CONTEXT_RESEND_WRITES (1) #define NFS_CONTEXT_BAD (2) - int error; + errseq_t wb_err; /* where wb errors are tracked */ + errseq_t wb_err_cursor; /* reporting cursor */ struct list_head list; struct nfs4_threshold *mdsthreshold; -- 2.9.3