diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c index 27caf4bebddc..d387b27c4ee2 100644 --- a/fs/erofs/decompressor.c +++ b/fs/erofs/decompressor.c @@ -7,8 +7,6 @@ #include "compress.h" #include -#define LZ4_MAX_DISTANCE_PAGES (DIV_ROUND_UP(LZ4_DISTANCE_MAX, PAGE_SIZE) + 1) - static int z_erofs_load_lz4_config(struct super_block *sb, struct erofs_super_block *dsb, void *data, int size) { @@ -21,8 +19,6 @@ static int z_erofs_load_lz4_config(struct super_block *sb, erofs_err(sb, "invalid lz4 cfgs, size=%u", size); return -EINVAL; } - distance = le16_to_cpu(lz4->max_distance); - sbi->lz4.max_pclusterblks = le16_to_cpu(lz4->max_pclusterblks); if (!sbi->lz4.max_pclusterblks) { sbi->lz4.max_pclusterblks = 1; /* reserved case */ @@ -39,45 +35,25 @@ static int z_erofs_load_lz4_config(struct super_block *sb, sbi->lz4.max_pclusterblks = 1; sbi->available_compr_algs = 1 << Z_EROFS_COMPRESSION_LZ4; } - - sbi->lz4.max_distance_pages = distance ? - DIV_ROUND_UP(distance, PAGE_SIZE) + 1 : - LZ4_MAX_DISTANCE_PAGES; return z_erofs_gbuf_growsize(sbi->lz4.max_pclusterblks); } /* - * Fill all gaps with bounce pages if it's a sparse page list. Also check if - * all physical pages are consecutive, which can be seen for moderate CR. + * Fill all gaps with bounce pages if it's a sparse page list (for example some + * folios are already uptodate and thus can be mapped into userspace). Also + * check if pages are physically consecutive, which can be seen for moderate CR. */ -static int z_erofs_lz4_prepare_dstpages(struct z_erofs_decompress_req *rq, - struct page **pagepool) +static int z_erofs_oneshot_prepare_dstpages(struct z_erofs_decompress_req *rq, + struct page **pagepool) { - struct page *availables[LZ4_MAX_DISTANCE_PAGES] = { NULL }; - unsigned long bounced[DIV_ROUND_UP(LZ4_MAX_DISTANCE_PAGES, - BITS_PER_LONG)] = { 0 }; - unsigned int lz4_max_distance_pages = - EROFS_SB(rq->sb)->lz4.max_distance_pages; void *kaddr = NULL; - unsigned int i, j, top; + unsigned int i; - top = 0; - for (i = j = 0; i < rq->outpages; ++i, ++j) { - struct page *const page = rq->out[i]; - struct page *victim; - - if (j >= lz4_max_distance_pages) - j = 0; - - /* 'valid' bounced can only be tested after a complete round */ - if (!rq->fillgaps && test_bit(j, bounced)) { - DBG_BUGON(i < lz4_max_distance_pages); - DBG_BUGON(top >= lz4_max_distance_pages); - availables[top++] = rq->out[i - lz4_max_distance_pages]; - } + for (i = 0; i < rq->outpages; ++i) { + struct page *page, *victim; + page = rq->out[i]; if (page) { - __clear_bit(j, bounced); if (!PageHighMem(page)) { if (!i) { kaddr = page_address(page); @@ -89,21 +65,14 @@ static int z_erofs_lz4_prepare_dstpages(struct z_erofs_decompress_req *rq, continue; } } - kaddr = NULL; - continue; - } - kaddr = NULL; - __set_bit(j, bounced); - - if (top) { - victim = availables[--top]; } else { victim = __erofs_allocpage(pagepool, rq->gfp, true); if (!victim) return -ENOMEM; set_page_private(victim, Z_EROFS_SHORTLIVED_PAGE); + rq->out[i] = victim; } - rq->out[i] = victim; + kaddr = NULL; } return kaddr ? 1 : 0; } @@ -266,7 +235,7 @@ static const char *z_erofs_lz4_decompress(struct z_erofs_decompress_req *rq, dst_maptype = 0; } else { /* general decoding path which can be used for all cases */ - ret = z_erofs_lz4_prepare_dstpages(rq, pagepool); + ret = z_erofs_oneshot_prepare_dstpages(rq, pagepool); if (ret < 0) return ERR_PTR(ret); if (ret > 0) { diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 65974e57aebf..12e3a5b80a5a 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -71,12 +71,8 @@ struct erofs_dev_context { bool flatdev; }; -/* all filesystem-wide lz4 configurations */ struct erofs_sb_lz4_info { - /* # of pages needed for EROFS lz4 rolling decompression */ - u16 max_distance_pages; - /* maximum possible blocks for pclusters in the filesystem */ - u16 max_pclusterblks; + u16 max_pclusterblks; /* maximum physical blocks for LZ4 pclusters */ }; struct erofs_xattr_prefix_item { diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index e1e25ca0d190..6b07e73ee2aa 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -1259,7 +1259,7 @@ static int z_erofs_decompress_pcluster(struct z_erofs_backend *be, bool eio) const struct z_erofs_decompressor *alg = z_erofs_decomp[pcl->algorithmformat]; bool try_free = true; - int i, j, jtop, err2, err = eio ? -EIO : 0; + int i, err2, err = eio ? -EIO : 0; struct page *page; bool overlapped; const char *reason; @@ -1348,7 +1348,6 @@ static int z_erofs_decompress_pcluster(struct z_erofs_backend *be, bool eio) be->compressed_pages >= be->onstack_pages + Z_EROFS_ONSTACK_PAGES) kvfree(be->compressed_pages); - jtop = 0; z_erofs_fill_other_copies(be, err); for (i = 0; i < be->nr_pages; ++i) { page = be->decompressed_pages[i]; @@ -1356,22 +1355,11 @@ static int z_erofs_decompress_pcluster(struct z_erofs_backend *be, bool eio) continue; DBG_BUGON(z_erofs_page_is_invalidated(page)); - if (!z_erofs_is_shortlived_page(page)) { + if (!z_erofs_is_shortlived_page(page)) erofs_onlinefolio_end(page_folio(page), err, true); - continue; - } - if (pcl->algorithmformat != Z_EROFS_COMPRESSION_LZ4) { + else erofs_pagepool_add(be->pagepool, page); - continue; - } - for (j = 0; j < jtop && be->decompressed_pages[j] != page; ++j) - ; - if (j >= jtop) /* this bounce page is newly detected */ - be->decompressed_pages[jtop++] = page; } - while (jtop) - erofs_pagepool_add(be->pagepool, - be->decompressed_pages[--jtop]); if (be->decompressed_pages != be->onstack_pages) kvfree(be->decompressed_pages);