From 966edfb0a3dc2adf5aab461c298fa0feb02f49d6 Mon Sep 17 00:00:00 2001 From: Gao Xiang Date: Mon, 11 Oct 2021 05:31:44 +0800 Subject: [PATCH] erofs: rename some generic methods in decompressor Previously, some LZ4 methods were named with `generic'. However, while evaluating the effective LZMA approach, it seems they aren't quite generic at all (e.g. no need preparing dstpages for most LZMA cases.) Avoid such naming instead. Link: https://lore.kernel.org/r/20211010213145.17462-7-xiang@kernel.org Acked-by: Chao Yu Signed-off-by: Gao Xiang --- fs/erofs/decompressor.c | 63 ++++++++++++++++++++--------------------- 1 file changed, 30 insertions(+), 33 deletions(-) diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c index dce06ac61893..8fd7af9d6b38 100644 --- a/fs/erofs/decompressor.c +++ b/fs/erofs/decompressor.c @@ -17,13 +17,8 @@ #endif struct z_erofs_decompressor { - /* - * if destpages have sparsed pages, fill them with bounce pages. - * it also check whether destpages indicate continuous physical memory. - */ - int (*prepare_destpages)(struct z_erofs_decompress_req *rq, - struct list_head *pagepool); - int (*decompress)(struct z_erofs_decompress_req *rq, u8 *out); + int (*decompress)(struct z_erofs_decompress_req *rq, + struct list_head *pagepool); char *name; }; @@ -63,8 +58,12 @@ int z_erofs_load_lz4_config(struct super_block *sb, return erofs_pcpubuf_growsize(sbi->lz4.max_pclusterblks); } -static int z_erofs_lz4_prepare_destpages(struct z_erofs_decompress_req *rq, - struct list_head *pagepool) +/* + * 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. + */ +static int z_erofs_lz4_prepare_dstpages(struct z_erofs_decompress_req *rq, + struct list_head *pagepool) { const unsigned int nr = PAGE_ALIGN(rq->pageofs_out + rq->outputsize) >> PAGE_SHIFT; @@ -119,7 +118,7 @@ static int z_erofs_lz4_prepare_destpages(struct z_erofs_decompress_req *rq, return kaddr ? 1 : 0; } -static void *z_erofs_handle_inplace_io(struct z_erofs_decompress_req *rq, +static void *z_erofs_lz4_handle_inplace_io(struct z_erofs_decompress_req *rq, void *inpage, unsigned int *inputmargin, int *maptype, bool support_0padding) { @@ -189,7 +188,8 @@ docopy: return src; } -static int z_erofs_lz4_decompress(struct z_erofs_decompress_req *rq, u8 *out) +static int z_erofs_lz4_decompress_mem(struct z_erofs_decompress_req *rq, + u8 *out) { unsigned int inputmargin; u8 *headpage, *src; @@ -216,8 +216,8 @@ static int z_erofs_lz4_decompress(struct z_erofs_decompress_req *rq, u8 *out) } rq->inputsize -= inputmargin; - src = z_erofs_handle_inplace_io(rq, headpage, &inputmargin, &maptype, - support_0padding); + src = z_erofs_lz4_handle_inplace_io(rq, headpage, &inputmargin, + &maptype, support_0padding); if (IS_ERR(src)) return PTR_ERR(src); @@ -259,23 +259,11 @@ static int z_erofs_lz4_decompress(struct z_erofs_decompress_req *rq, u8 *out) return ret; } -static struct z_erofs_decompressor decompressors[] = { - [Z_EROFS_COMPRESSION_SHIFTED] = { - .name = "shifted" - }, - [Z_EROFS_COMPRESSION_LZ4] = { - .prepare_destpages = z_erofs_lz4_prepare_destpages, - .decompress = z_erofs_lz4_decompress, - .name = "lz4" - }, -}; - -static int z_erofs_decompress_generic(struct z_erofs_decompress_req *rq, - struct list_head *pagepool) +static int z_erofs_lz4_decompress(struct z_erofs_decompress_req *rq, + struct list_head *pagepool) { const unsigned int nrpages_out = PAGE_ALIGN(rq->pageofs_out + rq->outputsize) >> PAGE_SHIFT; - const struct z_erofs_decompressor *alg = decompressors + rq->alg; unsigned int dst_maptype; void *dst; int ret; @@ -289,7 +277,7 @@ static int z_erofs_decompress_generic(struct z_erofs_decompress_req *rq, } /* general decoding path which can be used for all cases */ - ret = alg->prepare_destpages(rq, pagepool); + ret = z_erofs_lz4_prepare_dstpages(rq, pagepool); if (ret < 0) return ret; if (ret) { @@ -304,7 +292,7 @@ static int z_erofs_decompress_generic(struct z_erofs_decompress_req *rq, dst_maptype = 2; dstmap_out: - ret = alg->decompress(rq, dst + rq->pageofs_out); + ret = z_erofs_lz4_decompress_mem(rq, dst + rq->pageofs_out); if (!dst_maptype) kunmap_atomic(dst); @@ -313,7 +301,7 @@ dstmap_out: return ret; } -static int z_erofs_shifted_transform(const struct z_erofs_decompress_req *rq, +static int z_erofs_shifted_transform(struct z_erofs_decompress_req *rq, struct list_head *pagepool) { const unsigned int nrpages_out = @@ -352,10 +340,19 @@ static int z_erofs_shifted_transform(const struct z_erofs_decompress_req *rq, return 0; } +static struct z_erofs_decompressor decompressors[] = { + [Z_EROFS_COMPRESSION_SHIFTED] = { + .decompress = z_erofs_shifted_transform, + .name = "shifted" + }, + [Z_EROFS_COMPRESSION_LZ4] = { + .decompress = z_erofs_lz4_decompress, + .name = "lz4" + }, +}; + int z_erofs_decompress(struct z_erofs_decompress_req *rq, struct list_head *pagepool) { - if (rq->alg == Z_EROFS_COMPRESSION_SHIFTED) - return z_erofs_shifted_transform(rq, pagepool); - return z_erofs_decompress_generic(rq, pagepool); + return decompressors[rq->alg].decompress(rq, pagepool); }