diff options
Diffstat (limited to 'fs/erofs')
| -rw-r--r-- | fs/erofs/zdata.c | 71 |
1 files changed, 38 insertions, 33 deletions
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index 424f656cd765..a0bae499c5ff 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -1428,6 +1428,7 @@ static void z_erofs_fill_bio_vec(struct bio_vec *bvec, struct z_erofs_bvec zbv; struct address_space *mapping; struct folio *folio; + struct page *page; int bs = i_blocksize(f->inode); /* Except for inplace folios, the entire folio can be used for I/Os */ @@ -1450,7 +1451,6 @@ repeat: * file-backed folios will be used instead. */ if (folio->private == (void *)Z_EROFS_PREALLOCATED_PAGE) { - folio->private = 0; tocache = true; goto out_tocache; } @@ -1468,7 +1468,7 @@ repeat: } folio_lock(folio); - if (folio->mapping == mc) { + if (likely(folio->mapping == mc)) { /* * The cached folio is still in managed cache but without * a valid `->private` pcluster hint. Let's reconnect them. @@ -1478,41 +1478,44 @@ repeat: /* compressed_bvecs[] already takes a ref before */ folio_put(folio); } - - /* no need to submit if it is already up-to-date */ - if (folio_test_uptodate(folio)) { - folio_unlock(folio); - bvec->bv_page = NULL; + if (likely(folio->private == pcl)) { + /* don't submit cache I/Os again if already uptodate */ + if (folio_test_uptodate(folio)) { + folio_unlock(folio); + bvec->bv_page = NULL; + } + return; } - return; + /* + * Already linked with another pcluster, which only appears in + * crafted images by fuzzers for now. But handle this anyway. + */ + tocache = false; /* use temporary short-lived pages */ + } else { + DBG_BUGON(1); /* referenced managed folios can't be truncated */ + tocache = true; } - - /* - * It has been truncated, so it's unsafe to reuse this one. Let's - * allocate a new page for compressed data. - */ - DBG_BUGON(folio->mapping); - tocache = true; folio_unlock(folio); folio_put(folio); out_allocfolio: - zbv.page = erofs_allocpage(&f->pagepool, gfp | __GFP_NOFAIL); + page = erofs_allocpage(&f->pagepool, gfp | __GFP_NOFAIL); spin_lock(&pcl->obj.lockref.lock); - if (pcl->compressed_bvecs[nr].page) { - erofs_pagepool_add(&f->pagepool, zbv.page); + if (unlikely(pcl->compressed_bvecs[nr].page != zbv.page)) { + erofs_pagepool_add(&f->pagepool, page); spin_unlock(&pcl->obj.lockref.lock); cond_resched(); goto repeat; } - bvec->bv_page = pcl->compressed_bvecs[nr].page = zbv.page; - folio = page_folio(zbv.page); - /* first mark it as a temporary shortlived folio (now 1 ref) */ - folio->private = (void *)Z_EROFS_SHORTLIVED_PAGE; + bvec->bv_page = pcl->compressed_bvecs[nr].page = page; + folio = page_folio(page); spin_unlock(&pcl->obj.lockref.lock); out_tocache: if (!tocache || bs != PAGE_SIZE || - filemap_add_folio(mc, folio, pcl->obj.index + nr, gfp)) + filemap_add_folio(mc, folio, pcl->obj.index + nr, gfp)) { + /* turn into a temporary shortlived folio (1 ref) */ + folio->private = (void *)Z_EROFS_SHORTLIVED_PAGE; return; + } folio_attach_private(folio, pcl); /* drop a refcount added by allocpage (then 2 refs in total here) */ folio_put(folio); @@ -1647,13 +1650,10 @@ static void z_erofs_submit_queue(struct z_erofs_decompress_frontend *f, cur = mdev.m_pa; end = cur + pcl->pclustersize; do { - z_erofs_fill_bio_vec(&bvec, f, pcl, i++, mc); - if (!bvec.bv_page) - continue; - + bvec.bv_page = NULL; if (bio && (cur != last_pa || bio->bi_bdev != mdev.m_bdev)) { -io_retry: +drain_io: if (!erofs_is_fscache_mode(sb)) submit_bio(bio); else @@ -1666,6 +1666,15 @@ io_retry: bio = NULL; } + if (!bvec.bv_page) { + z_erofs_fill_bio_vec(&bvec, f, pcl, i++, mc); + if (!bvec.bv_page) + continue; + if (cur + bvec.bv_len > end) + bvec.bv_len = end - cur; + DBG_BUGON(bvec.bv_len < sb->s_blocksize); + } + if (unlikely(PageWorkingset(bvec.bv_page)) && !memstall) { psi_memstall_enter(&pflags); @@ -1685,13 +1694,9 @@ io_retry: ++nr_bios; } - if (cur + bvec.bv_len > end) - bvec.bv_len = end - cur; - DBG_BUGON(bvec.bv_len < sb->s_blocksize); if (!bio_add_page(bio, bvec.bv_page, bvec.bv_len, bvec.bv_offset)) - goto io_retry; - + goto drain_io; last_pa = cur + bvec.bv_len; bypass = false; } while ((cur += bvec.bv_len) < end); |