NFS: Fix spurious EIO read errors

If the client attempts to read a page, but the read fails due to some
spurious error (e.g. an ACCESS error or a timeout, ...) then we need
to allow other processes to retry.
Also try to report errors correctly when doing a synchronous readpage.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Trond Myklebust 2019-08-15 12:26:05 -04:00
parent 7af46292da
commit 8f54c7a4ba
3 changed files with 36 additions and 21 deletions

View File

@ -775,3 +775,13 @@ static inline bool nfs_error_is_fatal(int err)
}
}
static inline bool nfs_error_is_fatal_on_server(int err)
{
switch (err) {
case 0:
case -ERESTARTSYS:
case -EINTR:
return false;
}
return nfs_error_is_fatal(err);
}

View File

@ -91,19 +91,25 @@ void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio)
}
EXPORT_SYMBOL_GPL(nfs_pageio_reset_read_mds);
static void nfs_readpage_release(struct nfs_page *req)
static void nfs_readpage_release(struct nfs_page *req, int error)
{
struct inode *inode = d_inode(nfs_req_openctx(req)->dentry);
struct page *page = req->wb_page;
dprintk("NFS: read done (%s/%llu %d@%lld)\n", inode->i_sb->s_id,
(unsigned long long)NFS_FILEID(inode), req->wb_bytes,
(long long)req_offset(req));
if (nfs_error_is_fatal_on_server(error) && error != -ETIMEDOUT)
SetPageError(page);
if (nfs_page_group_sync_on_bit(req, PG_UNLOCKPAGE)) {
if (PageUptodate(req->wb_page))
nfs_readpage_to_fscache(inode, req->wb_page, 0);
struct address_space *mapping = page_file_mapping(page);
unlock_page(req->wb_page);
if (PageUptodate(page))
nfs_readpage_to_fscache(inode, page, 0);
else if (!PageError(page) && !PagePrivate(page))
generic_error_remove_page(mapping, page);
unlock_page(page);
}
nfs_release_request(req);
}
@ -131,7 +137,7 @@ int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode,
&nfs_async_read_completion_ops);
if (!nfs_pageio_add_request(&pgio, new)) {
nfs_list_remove_request(new);
nfs_readpage_release(new);
nfs_readpage_release(new, pgio.pg_error);
}
nfs_pageio_complete(&pgio);
@ -153,6 +159,7 @@ static void nfs_page_group_set_uptodate(struct nfs_page *req)
static void nfs_read_completion(struct nfs_pgio_header *hdr)
{
unsigned long bytes = 0;
int error;
if (test_bit(NFS_IOHDR_REDO, &hdr->flags))
goto out;
@ -179,14 +186,19 @@ static void nfs_read_completion(struct nfs_pgio_header *hdr)
zero_user_segment(page, start, end);
}
}
error = 0;
bytes += req->wb_bytes;
if (test_bit(NFS_IOHDR_ERROR, &hdr->flags)) {
if (bytes <= hdr->good_bytes)
nfs_page_group_set_uptodate(req);
else {
error = hdr->error;
xchg(&nfs_req_openctx(req)->error, error);
}
} else
nfs_page_group_set_uptodate(req);
nfs_list_remove_request(req);
nfs_readpage_release(req);
nfs_readpage_release(req, error);
}
out:
hdr->release(hdr);
@ -213,7 +225,7 @@ nfs_async_read_error(struct list_head *head, int error)
while (!list_empty(head)) {
req = nfs_list_entry(head->next);
nfs_list_remove_request(req);
nfs_readpage_release(req);
nfs_readpage_release(req, error);
}
}
@ -337,8 +349,13 @@ int nfs_readpage(struct file *file, struct page *page)
goto out;
}
xchg(&ctx->error, 0);
error = nfs_readpage_async(ctx, inode, page);
if (!error) {
error = wait_on_page_locked_killable(page);
if (!PageUptodate(page) && !error)
error = xchg(&ctx->error, 0);
}
out:
put_nfs_open_context(ctx);
return error;
@ -372,8 +389,8 @@ readpage_async_filler(void *data, struct page *page)
zero_user_segment(page, len, PAGE_SIZE);
if (!nfs_pageio_add_request(desc->pgio, new)) {
nfs_list_remove_request(new);
nfs_readpage_release(new);
error = desc->pgio->pg_error;
nfs_readpage_release(new, error);
goto out;
}
return 0;

View File

@ -599,18 +599,6 @@ static void nfs_write_error(struct nfs_page *req, int error)
nfs_release_request(req);
}
static bool
nfs_error_is_fatal_on_server(int err)
{
switch (err) {
case 0:
case -ERESTARTSYS:
case -EINTR:
return false;
}
return nfs_error_is_fatal(err);
}
/*
* Find an associated nfs write request, and prepare to flush it out
* May return an error if the user signalled nfs_wait_on_request().