erofs: introduce `z_erofs_parse_out_bvecs()'

`z_erofs_decompress_pcluster()' is too long therefore it'd be better
to introduce another helper to parse decompressed pages (or laterly,
decompressed bvecs.)

BTW, since `decompressed_bvecs' is too long as a part of the function
name, `out_bvecs' is used instead.

Reviewed-by: Yue Hu <huyue2@coolpad.com>
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220715154203.48093-4-hsiangkao@linux.alibaba.com

diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index c7be447ac64d18a06cb271543d74b74030762188..c183cd0bc42bbe2bb0c554b66e5d929541ef47b6 100644 (file)
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -778,18 +778,58 @@ static bool z_erofs_page_is_invalidated(struct page *page)
        return !page->mapping && !z_erofs_is_shortlived_page(page);
 }
 
+static int z_erofs_parse_out_bvecs(struct z_erofs_pcluster *pcl,
+                                  struct page **pages, struct page **pagepool)
+{
+       struct z_erofs_pagevec_ctor ctor;
+       enum z_erofs_page_type page_type;
+       int i, err = 0;
+
+       z_erofs_pagevec_ctor_init(&ctor, Z_EROFS_NR_INLINE_PAGEVECS,
+                                 pcl->pagevec, 0);
+       for (i = 0; i < pcl->vcnt; ++i) {
+               struct page *page = z_erofs_pagevec_dequeue(&ctor, &page_type);
+               unsigned int pagenr;
+
+               /* all pages in pagevec ought to be valid */
+               DBG_BUGON(!page);
+               DBG_BUGON(z_erofs_page_is_invalidated(page));
+
+               if (z_erofs_put_shortlivedpage(pagepool, page))
+                       continue;
+
+               if (page_type == Z_EROFS_VLE_PAGE_TYPE_HEAD)
+                       pagenr = 0;
+               else
+                       pagenr = z_erofs_onlinepage_index(page);
+
+               DBG_BUGON(pagenr >= pcl->nr_pages);
+               /*
+                * currently EROFS doesn't support multiref(dedup),
+                * so here erroring out one multiref page.
+                */
+               if (pages[pagenr]) {
+                       DBG_BUGON(1);
+                       SetPageError(pages[pagenr]);
+                       z_erofs_onlinepage_endio(pages[pagenr]);
+                       err = -EFSCORRUPTED;
+               }
+               pages[pagenr] = page;
+       }
+       z_erofs_pagevec_ctor_exit(&ctor, true);
+       return err;
+}
+
 static int z_erofs_decompress_pcluster(struct super_block *sb,
                                       struct z_erofs_pcluster *pcl,
                                       struct page **pagepool)
 {
        struct erofs_sb_info *const sbi = EROFS_SB(sb);
        unsigned int pclusterpages = z_erofs_pclusterpages(pcl);
-       struct z_erofs_pagevec_ctor ctor;
        unsigned int i, inputsize, outputsize, llen, nr_pages;
        struct page *pages_onstack[Z_EROFS_VMAP_ONSTACK_PAGES];
        struct page **pages, **compressed_pages, *page;
 
-       enum z_erofs_page_type page_type;
        bool overlapped, partial;
        int err;
 
@@ -823,42 +863,7 @@ static int z_erofs_decompress_pcluster(struct super_block *sb,
        for (i = 0; i < nr_pages; ++i)
                pages[i] = NULL;
 
-       err = 0;
-       z_erofs_pagevec_ctor_init(&ctor, Z_EROFS_NR_INLINE_PAGEVECS,
-                                 pcl->pagevec, 0);
-
-       for (i = 0; i < pcl->vcnt; ++i) {
-               unsigned int pagenr;
-
-               page = z_erofs_pagevec_dequeue(&ctor, &page_type);
-
-               /* all pages in pagevec ought to be valid */
-               DBG_BUGON(!page);
-               DBG_BUGON(z_erofs_page_is_invalidated(page));
-
-               if (z_erofs_put_shortlivedpage(pagepool, page))
-                       continue;
-
-               if (page_type == Z_EROFS_VLE_PAGE_TYPE_HEAD)
-                       pagenr = 0;
-               else
-                       pagenr = z_erofs_onlinepage_index(page);
-
-               DBG_BUGON(pagenr >= nr_pages);
-
-               /*
-                * currently EROFS doesn't support multiref(dedup),
-                * so here erroring out one multiref page.
-                */
-               if (pages[pagenr]) {
-                       DBG_BUGON(1);
-                       SetPageError(pages[pagenr]);
-                       z_erofs_onlinepage_endio(pages[pagenr]);
-                       err = -EFSCORRUPTED;
-               }
-               pages[pagenr] = page;
-       }
-       z_erofs_pagevec_ctor_exit(&ctor, true);
+       err = z_erofs_parse_out_bvecs(pcl, pages, pagepool);
 
        overlapped = false;
        compressed_pages = pcl->compressed_pages;