[PATCH v3 8/8] staging: erofs: integrate decompression inplace

From: Gao Xiang
Date: Mon Jun 24 2019 - 03:24:17 EST


From: Gao Xiang <gaoxiang25@xxxxxxxxxx>

Decompressor needs to know whether it's a partial
or full decompression since only full decompression
can be decompressed in-place.

On kirin980 platform, sequential read is finally
increased to 812MiB/s after decompression inplace
is enabled.

Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
---
drivers/staging/erofs/internal.h | 3 +++
drivers/staging/erofs/unzip_vle.c | 15 +++++++++++----
drivers/staging/erofs/unzip_vle.h | 1 +
drivers/staging/erofs/zmap.c | 1 +
4 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h
index 6c8767d4a1d5..963cc1b8b896 100644
--- a/drivers/staging/erofs/internal.h
+++ b/drivers/staging/erofs/internal.h
@@ -441,6 +441,7 @@ extern const struct address_space_operations z_erofs_vle_normalaccess_aops;
*/
enum {
BH_Zipped = BH_PrivateStart,
+ BH_FullMapped,
};

/* Has a disk mapping */
@@ -449,6 +450,8 @@ enum {
#define EROFS_MAP_META (1 << BH_Meta)
/* The extent has been compressed */
#define EROFS_MAP_ZIPPED (1 << BH_Zipped)
+/* The length of extent is full */
+#define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped)

struct erofs_map_blocks {
erofs_off_t m_pa, m_la;
diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c
index cb870b83f3c8..316382d33783 100644
--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -469,6 +469,9 @@ z_erofs_vle_work_register(const struct z_erofs_vle_work_finder *f,
Z_EROFS_VLE_WORKGRP_FMT_LZ4 :
Z_EROFS_VLE_WORKGRP_FMT_PLAIN);

+ if (map->m_flags & EROFS_MAP_FULL_MAPPED)
+ grp->flags |= Z_EROFS_VLE_WORKGRP_FULL_LENGTH;
+
/* new workgrps have been claimed as type 1 */
WRITE_ONCE(grp->next, *f->owned_head);
/* primary and followed work for all new workgrps */
@@ -901,7 +904,7 @@ static int z_erofs_vle_unzip(struct super_block *sb,
unsigned int i, outputsize;

enum z_erofs_page_type page_type;
- bool overlapped;
+ bool overlapped, partial;
struct z_erofs_vle_work *work;
int err;

@@ -1009,10 +1012,13 @@ static int z_erofs_vle_unzip(struct super_block *sb,
if (unlikely(err))
goto out;

- if (nr_pages << PAGE_SHIFT >= work->pageofs + grp->llen)
+ if (nr_pages << PAGE_SHIFT >= work->pageofs + grp->llen) {
outputsize = grp->llen;
- else
+ partial = !(grp->flags & Z_EROFS_VLE_WORKGRP_FULL_LENGTH);
+ } else {
outputsize = (nr_pages << PAGE_SHIFT) - work->pageofs;
+ partial = true;
+ }

if (z_erofs_vle_workgrp_fmt(grp) == Z_EROFS_VLE_WORKGRP_FMT_PLAIN)
algorithm = Z_EROFS_COMPRESSION_SHIFTED;
@@ -1028,7 +1034,8 @@ static int z_erofs_vle_unzip(struct super_block *sb,
.outputsize = outputsize,
.alg = algorithm,
.inplace_io = overlapped,
- .partial_decoding = true }, page_pool);
+ .partial_decoding = partial
+ }, page_pool);

out:
/* must handle all compressed pages before endding pages */
diff --git a/drivers/staging/erofs/unzip_vle.h b/drivers/staging/erofs/unzip_vle.h
index a2d9b60beebd..ab509d75aefd 100644
--- a/drivers/staging/erofs/unzip_vle.h
+++ b/drivers/staging/erofs/unzip_vle.h
@@ -46,6 +46,7 @@ struct z_erofs_vle_work {
#define Z_EROFS_VLE_WORKGRP_FMT_PLAIN 0
#define Z_EROFS_VLE_WORKGRP_FMT_LZ4 1
#define Z_EROFS_VLE_WORKGRP_FMT_MASK 1
+#define Z_EROFS_VLE_WORKGRP_FULL_LENGTH 2

typedef void *z_erofs_vle_owned_workgrp_t;

diff --git a/drivers/staging/erofs/zmap.c b/drivers/staging/erofs/zmap.c
index 1e75cef11db4..9c0bd65c46bf 100644
--- a/drivers/staging/erofs/zmap.c
+++ b/drivers/staging/erofs/zmap.c
@@ -424,6 +424,7 @@ int z_erofs_map_blocks_iter(struct inode *inode,
goto unmap_out;
}
end = (m.lcn << lclusterbits) | m.clusterofs;
+ map->m_flags |= EROFS_MAP_FULL_MAPPED;
m.delta[0] = 1;
/* fallthrough */
case Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD:
--
2.17.1