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 <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
This commit is contained in:
Gao Xiang 2021-10-11 05:31:44 +08:00
parent 0a434e0a2c
commit 966edfb0a3

View File

@ -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);
}