Commit a27c0858 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'erofs-for-5.16-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs 

Pull erofs fixes from Gao Xiang:

 - fix unsafe pagevec reuse which could cause unexpected behaviors

 - get rid of the unused DELAYEDALLOC strategy that has been replaced by
   TRYALLOC

* tag 'erofs-for-5.16-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: remove useless cache strategy of DELAYEDALLOC
  erofs: fix unsafe pagevec reuse of hooked pclusters
parents 5664896b 4c7e4255

fs/erofs/zdata.c

+7 −26
Original line number Diff line number Diff line
@@ -96,16 +96,9 @@ static void z_erofs_free_pcluster(struct z_erofs_pcluster *pcl) 
	DBG_BUGON(1);

}



/*

 * a compressed_pages[] placeholder in order to avoid

 * being filled with file pages for in-place decompression.

 */

#define PAGE_UNALLOCATED     ((void *)0x5F0E4B1D)



/* how to allocate cached pages for a pcluster */

enum z_erofs_cache_alloctype {

	DONTALLOC,	/* don't allocate any cached pages */

	DELAYEDALLOC,	/* delayed allocation (at the time of submitting io) */

	/*

	 * try to use cached I/O if page allocation succeeds or fallback

	 * to in-place I/O instead to avoid any direct reclaim.
@@ -267,10 +260,6 @@ static void preload_compressed_pages(struct z_erofs_collector *clt, 
			/* I/O is needed, no possible to decompress directly */

			standalone = false;

			switch (type) {

			case DELAYEDALLOC:

				t = tagptr_init(compressed_page_t,

						PAGE_UNALLOCATED);

				break;

			case TRYALLOC:

				newpage = erofs_allocpage(pagepool, gfp);

				if (!newpage)
@@ -371,8 +360,8 @@ static bool z_erofs_try_inplace_io(struct z_erofs_collector *clt, 


/* callers must be with collection lock held */

static int z_erofs_attach_page(struct z_erofs_collector *clt,

			       struct page *page,

			       enum z_erofs_page_type type)

			       struct page *page, enum z_erofs_page_type type,

			       bool pvec_safereuse)

{

	int ret;
@@ -382,9 +371,9 @@ static int z_erofs_attach_page(struct z_erofs_collector *clt, 
	    z_erofs_try_inplace_io(clt, page))

		return 0;



	ret = z_erofs_pagevec_enqueue(&clt->vector, page, type);

	ret = z_erofs_pagevec_enqueue(&clt->vector, page, type,

				      pvec_safereuse);

	clt->cl->vcnt += (unsigned int)ret;



	return ret ? 0 : -EAGAIN;

}
@@ -727,7 +716,8 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe, 
		tight &= (clt->mode >= COLLECT_PRIMARY_FOLLOWED);



retry:

	err = z_erofs_attach_page(clt, page, page_type);

	err = z_erofs_attach_page(clt, page, page_type,

				  clt->mode >= COLLECT_PRIMARY_FOLLOWED);

	/* should allocate an additional short-lived page for pagevec */

	if (err == -EAGAIN) {

		struct page *const newpage =
@@ -735,7 +725,7 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe, 


		set_page_private(newpage, Z_EROFS_SHORTLIVED_PAGE);

		err = z_erofs_attach_page(clt, newpage,

					  Z_EROFS_PAGE_TYPE_EXCLUSIVE);

					  Z_EROFS_PAGE_TYPE_EXCLUSIVE, true);

		if (!err)

			goto retry;

	}
@@ -1089,15 +1079,6 @@ static struct page *pickup_page_for_submission(struct z_erofs_pcluster *pcl, 
	if (!page)

		goto out_allocpage;



	/*

	 * the cached page has not been allocated and

	 * an placeholder is out there, prepare it now.

	 */

	if (page == PAGE_UNALLOCATED) {

		tocache = true;

		goto out_allocpage;

	}



	/* process the target tagged pointer */

	t = tagptr_init(compressed_page_t, page);

	justfound = tagptr_unfold_tags(t);

fs/erofs/zdata.h

+0 −1
Original line number Diff line number Diff line
@@ -179,4 +179,3 @@ static inline void z_erofs_onlinepage_endio(struct page *page) 
#define Z_EROFS_VMAP_GLOBAL_PAGES	2048



#endif

fs/erofs/zpvec.h

+10 −3
Original line number Diff line number Diff line
@@ -106,11 +106,18 @@ static inline void z_erofs_pagevec_ctor_init(struct z_erofs_pagevec_ctor *ctor, 


static inline bool z_erofs_pagevec_enqueue(struct z_erofs_pagevec_ctor *ctor,

					   struct page *page,

					   enum z_erofs_page_type type)

					   enum z_erofs_page_type type,

					   bool pvec_safereuse)

{

	if (!ctor->next && type)

		if (ctor->index + 1 == ctor->nr)

	if (!ctor->next) {

		/* some pages cannot be reused as pvec safely without I/O */

		if (type == Z_EROFS_PAGE_TYPE_EXCLUSIVE && !pvec_safereuse)

			type = Z_EROFS_VLE_PAGE_TYPE_TAIL_SHARED;



		if (type != Z_EROFS_PAGE_TYPE_EXCLUSIVE &&

		    ctor->index + 1 == ctor->nr)

			return false;

	}



	if (ctor->index >= ctor->nr)

		z_erofs_pagevec_ctor_pagedown(ctor, false);