[PATCH 3/4] erofs-utils: prepare for per-(sub)file compress strategies
Gao Xiang
xiang at kernel.org
Mon May 10 17:23:02 AEST 2021
In order to adjust pclustersize on the per-(sub)file basis,
generating per-file map headers are needed instead.
In addition to that, we could use COMPACT_4B on the per-file
basis as well after this patch.
Signed-off-by: Gao Xiang <xiang at kernel.org>
---
lib/compress.c | 80 +++++++++++++++++++++++++++++++++-----------------
1 file changed, 53 insertions(+), 27 deletions(-)
diff --git a/lib/compress.c b/lib/compress.c
index e146416890f0..89f87dc4096c 100644
--- a/lib/compress.c
+++ b/lib/compress.c
@@ -22,7 +22,7 @@
static struct erofs_compress compresshandle;
static int compressionlevel;
-static struct z_erofs_map_header mapheader;
+static unsigned int algorithmtype[2];
struct z_erofs_vle_compress_ctx {
u8 *metacur;
@@ -149,12 +149,17 @@ static int write_uncompressed_extent(struct z_erofs_vle_compress_ctx *ctx,
return count;
}
+/* TODO: apply per-(sub)file strategies here */
+static unsigned int z_erofs_get_max_pclustersize(struct erofs_inode *inode)
+{
+ return cfg.c_physical_clusterblks * EROFS_BLKSIZ;
+}
+
static int vle_compress_one(struct erofs_inode *inode,
struct z_erofs_vle_compress_ctx *ctx,
bool final)
{
- const unsigned int pclusterblks = cfg.c_physical_clusterblks;
- const unsigned int pclustersize = pclusterblks * EROFS_BLKSIZ;
+ const unsigned int pclustersize = z_erofs_get_max_pclustersize(inode);
struct erofs_compress *const h = &compresshandle;
unsigned int len = ctx->tail - ctx->head;
unsigned int count;
@@ -342,13 +347,14 @@ static void *write_compacted_indexes(u8 *out,
int z_erofs_convert_to_compacted_format(struct erofs_inode *inode,
erofs_blk_t blkaddr,
unsigned int legacymetasize,
- unsigned int logical_clusterbits)
+ void *compressmeta)
{
const unsigned int mpos = Z_EROFS_VLE_EXTENT_ALIGN(inode->inode_isize +
inode->xattr_isize) +
sizeof(struct z_erofs_map_header);
const unsigned int totalidx = (legacymetasize -
Z_EROFS_LEGACY_MAP_HEADER_SIZE) / 8;
+ const unsigned int logical_clusterbits = inode->z_logical_clusterbits;
u8 *out, *in;
struct z_erofs_compressindex_vec cv[16];
/* # of 8-byte units so that it can be aligned with 32 bytes */
@@ -379,9 +385,9 @@ int z_erofs_convert_to_compacted_format(struct erofs_inode *inode,
compacted_4b_end = totalidx;
}
- out = in = inode->compressmeta;
+ out = in = compressmeta;
- out += sizeof(mapheader);
+ out += sizeof(struct z_erofs_map_header);
in += Z_EROFS_LEGACY_MAP_HEADER_SIZE;
dummy_head = false;
@@ -428,11 +434,26 @@ int z_erofs_convert_to_compacted_format(struct erofs_inode *inode,
4, logical_clusterbits, true,
&dummy_head);
}
- inode->extent_isize = out - (u8 *)inode->compressmeta;
- inode->datalayout = EROFS_INODE_FLAT_COMPRESSION;
+ inode->extent_isize = out - (u8 *)compressmeta;
return 0;
}
+static void z_erofs_write_mapheader(struct erofs_inode *inode,
+ void *compressmeta)
+{
+ struct z_erofs_map_header h = {
+ .h_advise = cpu_to_le16(inode->z_advise),
+ .h_algorithmtype = inode->z_algorithmtype[1] << 4 |
+ inode->z_algorithmtype[0],
+ /* lclustersize */
+ .h_clusterbits = inode->z_logical_clusterbits - 12,
+ };
+
+ memset(compressmeta, 0, Z_EROFS_LEGACY_MAP_HEADER_SIZE);
+ /* write out map header */
+ memcpy(compressmeta, &h, sizeof(struct z_erofs_map_header));
+}
+
int erofs_write_compressed_file(struct erofs_inode *inode)
{
struct erofs_buffer_head *bh;
@@ -459,9 +480,25 @@ int erofs_write_compressed_file(struct erofs_inode *inode)
goto err_close;
}
- memset(compressmeta, 0, Z_EROFS_LEGACY_MAP_HEADER_SIZE);
- /* write out compressed header */
- memcpy(compressmeta, &mapheader, sizeof(mapheader));
+ /* initialize per-file compression setting */
+ inode->z_advise = 0;
+ if (!cfg.c_legacy_compress) {
+ inode->z_advise |= Z_EROFS_ADVISE_COMPACTED_2B;
+ inode->datalayout = EROFS_INODE_FLAT_COMPRESSION;
+ } else {
+ inode->datalayout = EROFS_INODE_FLAT_COMPRESSION_LEGACY;
+ }
+
+ if (cfg.c_physical_clusterblks > 1) {
+ inode->z_advise |= Z_EROFS_ADVISE_BIG_PCLUSTER_1;
+ if (inode->datalayout == EROFS_INODE_FLAT_COMPRESSION)
+ inode->z_advise |= Z_EROFS_ADVISE_BIG_PCLUSTER_2;
+ }
+ inode->z_algorithmtype[0] = algorithmtype[0];
+ inode->z_algorithmtype[1] = algorithmtype[1];
+ inode->z_logical_clusterbits = LOG_BLOCK_SIZE;
+
+ z_erofs_write_mapheader(inode, compressmeta);
blkaddr = erofs_mapbh(bh->block); /* start_blkaddr */
ctx.blkaddr = blkaddr;
@@ -516,19 +553,19 @@ int erofs_write_compressed_file(struct erofs_inode *inode)
* when both mkfs & kernel support compression inline.
*/
erofs_bdrop(bh, false);
- inode->compressmeta = compressmeta;
inode->idata_size = 0;
inode->u.i_blocks = compressed_blocks;
legacymetasize = ctx.metacur - compressmeta;
- if (cfg.c_legacy_compress) {
+ if (inode->datalayout == EROFS_INODE_FLAT_COMPRESSION_LEGACY) {
inode->extent_isize = legacymetasize;
- inode->datalayout = EROFS_INODE_FLAT_COMPRESSION_LEGACY;
} else {
ret = z_erofs_convert_to_compacted_format(inode, blkaddr,
- legacymetasize, 12);
+ legacymetasize,
+ compressmeta);
DBG_BUGON(ret);
}
+ inode->compressmeta = compressmeta;
return 0;
err_bdrop:
@@ -580,7 +617,6 @@ int z_erofs_build_compr_cfgs(struct erofs_buffer_head *sb_bh)
int z_erofs_compress_init(struct erofs_buffer_head *sb_bh)
{
- unsigned int algorithmtype[2];
/* initialize for primary compression algorithm */
int ret = erofs_compressor_init(&compresshandle,
cfg.c_compr_alg_master);
@@ -603,16 +639,13 @@ int z_erofs_compress_init(struct erofs_buffer_head *sb_bh)
compresshandle.alg->default_level :
cfg.c_compr_level_master;
- /* figure out mapheader */
+ /* figure out primary algorithm */
ret = erofs_get_compress_algorithm_id(cfg.c_compr_alg_master);
if (ret < 0)
return ret;
algorithmtype[0] = ret; /* primary algorithm (head 0) */
algorithmtype[1] = 0; /* secondary algorithm (head 1) */
- mapheader.h_advise = 0;
- if (!cfg.c_legacy_compress)
- mapheader.h_advise |= Z_EROFS_ADVISE_COMPACTED_2B;
/*
* if big pcluster is enabled, an extra CBLKCNT lcluster index needs
* to be loaded in order to get those compressed block counts.
@@ -625,15 +658,8 @@ int z_erofs_compress_init(struct erofs_buffer_head *sb_bh)
return -EINVAL;
}
erofs_sb_set_big_pcluster();
- mapheader.h_advise |= Z_EROFS_ADVISE_BIG_PCLUSTER_1;
- if (!cfg.c_legacy_compress)
- mapheader.h_advise |= Z_EROFS_ADVISE_BIG_PCLUSTER_2;
-
erofs_warn("EXPERIMENTAL big pcluster feature in use. Use at your own risk!");
}
- mapheader.h_algorithmtype = algorithmtype[1] << 4 |
- algorithmtype[0];
- mapheader.h_clusterbits = LOG_BLOCK_SIZE - 12;
if (erofs_sb_has_compr_cfgs()) {
sbi.available_compr_algs |= 1 << ret;
--
2.20.1
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