[PATCH 4.20 175/183] staging: erofs: unzip_{pagevec.h,vle.c}: rectify BUG_ONs

From: Greg Kroah-Hartman
Date: Mon Feb 25 2019 - 16:36:56 EST


4.20-stable review patch. If anyone has any objections, please let me know.

------------------

From: Gao Xiang <gaoxiang25@xxxxxxxxxx>

commit 70b17991d89554cdd16f3e4fb0179bcc03c808d9 upstream.

remove all redundant BUG_ONs, and turn the rest
useful usages to DBG_BUGONs.

Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>


---
drivers/staging/erofs/unzip_pagevec.h | 2 -
drivers/staging/erofs/unzip_vle.c | 35 +++++++++++++---------------------
2 files changed, 15 insertions(+), 22 deletions(-)

--- a/drivers/staging/erofs/unzip_pagevec.h
+++ b/drivers/staging/erofs/unzip_pagevec.h
@@ -150,7 +150,7 @@ z_erofs_pagevec_ctor_dequeue(struct z_er
erofs_vtptr_t t;

if (unlikely(ctor->index >= ctor->nr)) {
- BUG_ON(ctor->next == NULL);
+ DBG_BUGON(!ctor->next);
z_erofs_pagevec_ctor_pagedown(ctor, true);
}

--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -20,9 +20,6 @@ static struct kmem_cache *z_erofs_workgr

void z_erofs_exit_zip_subsystem(void)
{
- BUG_ON(z_erofs_workqueue == NULL);
- BUG_ON(z_erofs_workgroup_cachep == NULL);
-
destroy_workqueue(z_erofs_workqueue);
kmem_cache_destroy(z_erofs_workgroup_cachep);
}
@@ -366,7 +363,10 @@ z_erofs_vle_work_register(const struct z
struct z_erofs_vle_work *work;

/* if multiref is disabled, grp should never be nullptr */
- BUG_ON(grp != NULL);
+ if (unlikely(grp)) {
+ DBG_BUGON(1);
+ return ERR_PTR(-EINVAL);
+ }

/* no available workgroup, let's allocate one */
grp = kmem_cache_zalloc(z_erofs_workgroup_cachep, GFP_NOFS);
@@ -745,7 +745,7 @@ static inline void z_erofs_vle_read_endi
bool cachemngd = false;

DBG_BUGON(PageUptodate(page));
- BUG_ON(page->mapping == NULL);
+ DBG_BUGON(!page->mapping);

#ifdef EROFS_FS_HAS_MANAGED_CACHE
if (unlikely(mngda == NULL && !z_erofs_is_stagingpage(page))) {
@@ -803,7 +803,7 @@ static int z_erofs_vle_unzip(struct supe

might_sleep();
work = z_erofs_vle_grab_primary_work(grp);
- BUG_ON(!READ_ONCE(work->nr_pages));
+ DBG_BUGON(!READ_ONCE(work->nr_pages));

mutex_lock(&work->lock);
nr_pages = work->nr_pages;
@@ -852,8 +852,8 @@ repeat:
else
pagenr = z_erofs_onlinepage_index(page);

- BUG_ON(pagenr >= nr_pages);
- BUG_ON(pages[pagenr] != NULL);
+ DBG_BUGON(pagenr >= nr_pages);
+ DBG_BUGON(pages[pagenr]);

pages[pagenr] = page;
}
@@ -876,9 +876,8 @@ repeat:
if (z_erofs_is_stagingpage(page))
continue;
#ifdef EROFS_FS_HAS_MANAGED_CACHE
- else if (page->mapping == mngda) {
- BUG_ON(PageLocked(page));
- BUG_ON(!PageUptodate(page));
+ if (page->mapping == mngda) {
+ DBG_BUGON(!PageUptodate(page));
continue;
}
#endif
@@ -886,8 +885,8 @@ repeat:
/* only non-head page could be reused as a compressed page */
pagenr = z_erofs_onlinepage_index(page);

- BUG_ON(pagenr >= nr_pages);
- BUG_ON(pages[pagenr] != NULL);
+ DBG_BUGON(pagenr >= nr_pages);
+ DBG_BUGON(pages[pagenr]);
++sparsemem_pages;
pages[pagenr] = page;

@@ -897,9 +896,6 @@ repeat:
llen = (nr_pages << PAGE_SHIFT) - work->pageofs;

if (z_erofs_vle_workgrp_fmt(grp) == Z_EROFS_VLE_WORKGRP_FMT_PLAIN) {
- /* FIXME! this should be fixed in the future */
- BUG_ON(grp->llen != llen);
-
err = z_erofs_vle_plain_copy(compressed_pages, clusterpages,
pages, nr_pages, work->pageofs);
goto out;
@@ -914,10 +910,8 @@ repeat:
if (err != -ENOTSUPP)
goto out_percpu;

- if (sparsemem_pages >= nr_pages) {
- BUG_ON(sparsemem_pages > nr_pages);
+ if (sparsemem_pages >= nr_pages)
goto skip_allocpage;
- }

for (i = 0; i < nr_pages; ++i) {
if (pages[i] != NULL)
@@ -1010,7 +1004,7 @@ static void z_erofs_vle_unzip_wq(struct
struct z_erofs_vle_unzip_io_sb, io.u.work);
LIST_HEAD(page_pool);

- BUG_ON(iosb->io.head == Z_EROFS_VLE_WORKGRP_TAIL_CLOSED);
+ DBG_BUGON(iosb->io.head == Z_EROFS_VLE_WORKGRP_TAIL_CLOSED);
z_erofs_vle_unzip_all(iosb->sb, &iosb->io, &page_pool);

put_pages_list(&page_pool);
@@ -1344,7 +1338,6 @@ static int z_erofs_vle_normalaccess_read
continue;
}

- BUG_ON(PagePrivate(page));
set_page_private(page, (unsigned long)head);
head = page;
}