staging: erofs: fix error handling when failed to read compresssed data

Complete read error handling paths for all three kinds of
compressed pages:

 1) For cache-managed pages, PG_uptodate will be checked since
    read_endio will unlock and SetPageUptodate for these pages;

 2) For inplaced pages, read_endio cannot SetPageUptodate directly
    since it should be used to mark the final decompressed data,
    PG_error will be set with page locked for IO error instead;

 3) For staging pages, PG_error is used, which is similar to
    what we do for inplaced pages.

Fixes: 3883a79abd ("staging: erofs: introduce VLE decompression support")
Cc: <stable@vger.kernel.org> # 4.19+
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Gao Xiang 2019-03-25 11:40:07 +08:00 committed by Greg Kroah-Hartman
parent 3b9c2f2e0e
commit b6391ac734

View file

@ -972,6 +972,7 @@ repeat:
overlapped = false;
compressed_pages = grp->compressed_pages;
err = 0;
for (i = 0; i < clusterpages; ++i) {
unsigned int pagenr;
@ -981,26 +982,39 @@ repeat:
DBG_BUGON(!page);
DBG_BUGON(!page->mapping);
if (z_erofs_is_stagingpage(page))
continue;
if (!z_erofs_is_stagingpage(page)) {
#ifdef EROFS_FS_HAS_MANAGED_CACHE
if (page->mapping == MNGD_MAPPING(sbi)) {
DBG_BUGON(!PageUptodate(page));
continue;
}
if (page->mapping == MNGD_MAPPING(sbi)) {
if (unlikely(!PageUptodate(page)))
err = -EIO;
continue;
}
#endif
/* only non-head page could be reused as a compressed page */
pagenr = z_erofs_onlinepage_index(page);
/*
* only if non-head page can be selected
* for inplace decompression
*/
pagenr = z_erofs_onlinepage_index(page);
DBG_BUGON(pagenr >= nr_pages);
DBG_BUGON(pages[pagenr]);
++sparsemem_pages;
pages[pagenr] = page;
DBG_BUGON(pagenr >= nr_pages);
DBG_BUGON(pages[pagenr]);
++sparsemem_pages;
pages[pagenr] = page;
overlapped = true;
overlapped = true;
}
/* PG_error needs checking for inplaced and staging pages */
if (unlikely(PageError(page))) {
DBG_BUGON(PageUptodate(page));
err = -EIO;
}
}
if (unlikely(err))
goto out;
llen = (nr_pages << PAGE_SHIFT) - work->pageofs;
if (z_erofs_vle_workgrp_fmt(grp) == Z_EROFS_VLE_WORKGRP_FMT_PLAIN) {
@ -1198,6 +1212,7 @@ repeat:
if (page->mapping == mc) {
WRITE_ONCE(grp->compressed_pages[nr], page);
ClearPageError(page);
if (!PagePrivate(page)) {
/*
* impossible to be !PagePrivate(page) for