[PATCH AUTOSEL 5.2 49/94] NFS: Fix writepage(s) error handling to not report errors twice

Sasha Levin
2019-09-04T16:18:11Z

From: Trond Myklebust <trond.myklebust@hammerspace.com>

[ Upstream commit 96c4145599b30c0eb6cbeaa24207802452dd1872 ]

If writepage()/writepages() saw an error, but handled it without
reporting it, we should not be re-reporting that error on exit.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/nfs/write.c | 21 +++++++++++++--------
1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index f15dda5efb741..0d6d7beb85053 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -621,12 +621,12 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags));

/* If there is a fatal error that covers this write, just exit */
- ret = 0;
mapping = page_file_mapping(page);
- if (test_bit(AS_ENOSPC, &mapping->flags) ||
- test_bit(AS_EIO, &mapping->flags))
+ ret = pgio->pg_error;
+ if (nfs_error_is_fatal_on_server(ret))
goto out_launder;

+ ret = 0;
if (!nfs_pageio_add_request(pgio, req)) {
ret = pgio->pg_error;
/*
@@ -638,6 +638,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
} else
ret = -EAGAIN;
nfs_redirty_request(req);
+ pgio->pg_error = 0;
} else
nfs_add_stats(page_file_mapping(page)->host,
NFSIOS_WRITEPAGES, 1);
@@ -657,7 +658,7 @@ static int nfs_do_writepage(struct page *page, struct writeback_control *wbc,
ret = nfs_page_async_flush(pgio, page);
if (ret == -EAGAIN) {
redirty_page_for_writepage(wbc, page);
- ret = 0;
+ ret = AOP_WRITEPAGE_ACTIVATE;
}
return ret;
}
@@ -676,10 +677,11 @@ static int nfs_writepage_locked(struct page *page,
nfs_pageio_init_write(&pgio, inode, 0,
false, &nfs_async_write_completion_ops);
err = nfs_do_writepage(page, wbc, &pgio);
+ pgio.pg_error = 0;
nfs_pageio_complete(&pgio);
if (err < 0)
return err;
- if (pgio.pg_error < 0)
+ if (nfs_error_is_fatal(pgio.pg_error))
return pgio.pg_error;
return 0;
}
@@ -689,7 +691,8 @@ int nfs_writepage(struct page *page, struct writeback_control *wbc)
int ret;

ret = nfs_writepage_locked(page, wbc);
- unlock_page(page);
+ if (ret != AOP_WRITEPAGE_ACTIVATE)
+ unlock_page(page);
return ret;
}

@@ -698,7 +701,8 @@ static int nfs_writepages_callback(struct page *page, struct writeback_control *
int ret;

ret = nfs_do_writepage(page, wbc, data);
- unlock_page(page);
+ if (ret != AOP_WRITEPAGE_ACTIVATE)
+ unlock_page(page);
return ret;
}

@@ -725,6 +729,7 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
&nfs_async_write_completion_ops);
pgio.pg_io_completion = ioc;
err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio);
+ pgio.pg_error = 0;
nfs_pageio_complete(&pgio);
nfs_io_completion_put(ioc);

@@ -733,7 +738,7 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
if (err < 0)
goto out_err;
err = pgio.pg_error;
- if (err < 0)
+ if (nfs_error_is_fatal(err))
goto out_err;
return 0;
out_err:
--
2.20.1