[PATCH v3 5/5] erofs: add on-disk compressed tail-packing inline support
From: Gao Xiang
Date: Sat Dec 25 2021 - 02:07:07 EST
From: Yue Hu <huyue2@xxxxxxxxxx>
Introduces erofs compressed tail-packing inline support.
This approach adds a new field called `h_idata_size' in the
per-file compression header to indicate the encoded size of
each tail-packing pcluster.
At runtime, it will find the start logical offset of the tail
pcluster when initializing per-inode zmap and record such
extent (headlcn, idataoff) information to the in-memory inode.
Therefore, follow-on requests can directly recognize if one
pcluster is a tail-packing inline pcluster or not.
Signed-off-by: Yue Hu <huyue2@xxxxxxxxxx>
Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
---
fs/erofs/erofs_fs.h | 10 +++-
fs/erofs/internal.h | 6 +++
fs/erofs/super.c | 3 ++
fs/erofs/sysfs.c | 2 +
fs/erofs/zmap.c | 116 ++++++++++++++++++++++++++++++++------------
5 files changed, 105 insertions(+), 32 deletions(-)
diff --git a/fs/erofs/erofs_fs.h b/fs/erofs/erofs_fs.h
index dda79afb901d..3ea62c6fb00a 100644
--- a/fs/erofs/erofs_fs.h
+++ b/fs/erofs/erofs_fs.h
@@ -23,13 +23,15 @@
#define EROFS_FEATURE_INCOMPAT_CHUNKED_FILE 0x00000004
#define EROFS_FEATURE_INCOMPAT_DEVICE_TABLE 0x00000008
#define EROFS_FEATURE_INCOMPAT_COMPR_HEAD2 0x00000008
+#define EROFS_FEATURE_INCOMPAT_ZTAILPACKING 0x00000010
#define EROFS_ALL_FEATURE_INCOMPAT \
(EROFS_FEATURE_INCOMPAT_ZERO_PADDING | \
EROFS_FEATURE_INCOMPAT_COMPR_CFGS | \
EROFS_FEATURE_INCOMPAT_BIG_PCLUSTER | \
EROFS_FEATURE_INCOMPAT_CHUNKED_FILE | \
EROFS_FEATURE_INCOMPAT_DEVICE_TABLE | \
- EROFS_FEATURE_INCOMPAT_COMPR_HEAD2)
+ EROFS_FEATURE_INCOMPAT_COMPR_HEAD2 | \
+ EROFS_FEATURE_INCOMPAT_ZTAILPACKING)
#define EROFS_SB_EXTSLOT_SIZE 16
@@ -292,13 +294,17 @@ struct z_erofs_lzma_cfgs {
* (4B) + 2B + (4B) if compacted 2B is on.
* bit 1 : HEAD1 big pcluster (0 - off; 1 - on)
* bit 2 : HEAD2 big pcluster (0 - off; 1 - on)
+ * bit 3 : tailpacking inline pcluster (0 - off; 1 - on)
*/
#define Z_EROFS_ADVISE_COMPACTED_2B 0x0001
#define Z_EROFS_ADVISE_BIG_PCLUSTER_1 0x0002
#define Z_EROFS_ADVISE_BIG_PCLUSTER_2 0x0004
+#define Z_EROFS_ADVISE_INLINE_PCLUSTER 0x0008
struct z_erofs_map_header {
- __le32 h_reserved1;
+ __le16 h_reserved1;
+ /* indicates the encoded size of tailpacking data */
+ __le16 h_idata_size;
__le16 h_advise;
/*
* bit 0-3 : algorithm type of head 1 (logical cluster type 01);
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 8e70435629e5..ebb9ffa08dd2 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -274,6 +274,7 @@ EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
EROFS_FEATURE_FUNCS(compr_head2, incompat, INCOMPAT_COMPR_HEAD2)
+EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
/* atomic flag definitions */
@@ -308,6 +309,9 @@ struct erofs_inode {
unsigned short z_advise;
unsigned char z_algorithmtype[2];
unsigned char z_logical_clusterbits;
+ unsigned long z_idata_headlcn;
+ unsigned int z_idataoff;
+ unsigned short z_idata_size;
};
#endif /* CONFIG_EROFS_FS_ZIP */
};
@@ -421,6 +425,8 @@ struct erofs_map_blocks {
#define EROFS_GET_BLOCKS_FIEMAP 0x0002
/* Used to map the whole extent if non-negligible data is requested for LZMA */
#define EROFS_GET_BLOCKS_READMORE 0x0004
+/* Used to map tail extent for tailpacking inline pcluster */
+#define EROFS_GET_BLOCKS_FINDTAIL 0x0008
enum {
Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 58f381f80205..0724ad5fd6cf 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -411,6 +411,9 @@ static int erofs_read_superblock(struct super_block *sb)
/* handle multiple devices */
ret = erofs_init_devices(sb, dsb);
+
+ if (erofs_sb_has_ztailpacking(sbi))
+ erofs_info(sb, "EXPERIMENTAL compressed inline data feature in use. Use at your own risk!");
out:
kunmap(page);
put_page(page);
diff --git a/fs/erofs/sysfs.c b/fs/erofs/sysfs.c
index 666693432107..dac252bc9228 100644
--- a/fs/erofs/sysfs.c
+++ b/fs/erofs/sysfs.c
@@ -75,6 +75,7 @@ EROFS_ATTR_FEATURE(chunked_file);
EROFS_ATTR_FEATURE(device_table);
EROFS_ATTR_FEATURE(compr_head2);
EROFS_ATTR_FEATURE(sb_chksum);
+EROFS_ATTR_FEATURE(ztailpacking);
static struct attribute *erofs_feat_attrs[] = {
ATTR_LIST(zero_padding),
@@ -84,6 +85,7 @@ static struct attribute *erofs_feat_attrs[] = {
ATTR_LIST(device_table),
ATTR_LIST(compr_head2),
ATTR_LIST(sb_chksum),
+ ATTR_LIST(ztailpacking),
NULL,
};
ATTRIBUTE_GROUPS(erofs_feat);
diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index 660489a7fb64..52b5369f9b42 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -7,12 +7,17 @@
#include <asm/unaligned.h>
#include <trace/events/erofs.h>
+static int z_erofs_do_map_blocks(struct inode *inode,
+ struct erofs_map_blocks *map,
+ int flags);
+
int z_erofs_fill_inode(struct inode *inode)
{
struct erofs_inode *const vi = EROFS_I(inode);
struct erofs_sb_info *sbi = EROFS_SB(inode->i_sb);
if (!erofs_sb_has_big_pcluster(sbi) &&
+ !erofs_sb_has_ztailpacking(sbi) &&
vi->datalayout == EROFS_INODE_FLAT_COMPRESSION_LEGACY) {
vi->z_advise = 0;
vi->z_algorithmtype[0] = 0;
@@ -51,6 +56,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
goto out_unlock;
DBG_BUGON(!erofs_sb_has_big_pcluster(EROFS_SB(sb)) &&
+ !erofs_sb_has_ztailpacking(EROFS_SB(sb)) &&
vi->datalayout == EROFS_INODE_FLAT_COMPRESSION_LEGACY);
pos = ALIGN(iloc(EROFS_SB(sb), vi->nid) + vi->inode_isize +
@@ -65,6 +71,7 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
h = kaddr + erofs_blkoff(pos);
vi->z_advise = le16_to_cpu(h->h_advise);
+ vi->z_idata_size = le16_to_cpu(h->h_idata_size);
vi->z_algorithmtype[0] = h->h_algorithmtype & 15;
vi->z_algorithmtype[1] = h->h_algorithmtype >> 4;
@@ -94,13 +101,34 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
err = -EFSCORRUPTED;
goto unmap_done;
}
- /* paired with smp_mb() at the beginning of the function */
- smp_mb();
- set_bit(EROFS_I_Z_INITED_BIT, &vi->flags);
unmap_done:
kunmap_atomic(kaddr);
unlock_page(page);
put_page(page);
+ if (err)
+ goto out_unlock;
+
+ if (vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER) {
+ struct erofs_map_blocks map = { .mpage = NULL };
+
+ vi->z_idata_size = le16_to_cpu(h->h_idata_size);
+ err = z_erofs_do_map_blocks(inode, &map,
+ EROFS_GET_BLOCKS_FINDTAIL);
+ if (map.mpage)
+ put_page(map.mpage);
+
+ if (!map.m_plen ||
+ erofs_blkoff(map.m_pa) + map.m_plen > EROFS_BLKSIZ) {
+ erofs_err(sb, "invalid tail-packing pclustersize %llu",
+ map.m_plen);
+ err = -EFSCORRUPTED;
+ }
+ if (err < 0)
+ goto out_unlock;
+ }
+ /* paired with smp_mb() at the beginning of the function */
+ smp_mb();
+ set_bit(EROFS_I_Z_INITED_BIT, &vi->flags);
out_unlock:
clear_and_wake_up_bit(EROFS_I_BL_Z_BIT, &vi->flags);
return err;
@@ -117,6 +145,7 @@ struct z_erofs_maprecorder {
u16 clusterofs;
u16 delta[2];
erofs_blk_t pblk, compressedlcs;
+ erofs_off_t nextpackoff;
};
static int z_erofs_reload_indexes(struct z_erofs_maprecorder *m,
@@ -169,6 +198,7 @@ static int legacy_load_cluster_from_disk(struct z_erofs_maprecorder *m,
if (err)
return err;
+ m->nextpackoff = pos + sizeof(struct z_erofs_vle_decompressed_index);
m->lcn = lcn;
di = m->kaddr + erofs_blkoff(pos);
@@ -243,12 +273,12 @@ static int get_compacted_la_distance(unsigned int lclusterbits,
static int unpack_compacted_index(struct z_erofs_maprecorder *m,
unsigned int amortizedshift,
- unsigned int eofs, bool lookahead)
+ erofs_off_t pos, bool lookahead)
{
struct erofs_inode *const vi = EROFS_I(m->inode);
const unsigned int lclusterbits = vi->z_logical_clusterbits;
const unsigned int lomask = (1 << lclusterbits) - 1;
- unsigned int vcnt, base, lo, encodebits, nblk;
+ unsigned int vcnt, base, lo, encodebits, nblk, eofs;
int i;
u8 *in, type;
bool big_pcluster;
@@ -260,8 +290,12 @@ static int unpack_compacted_index(struct z_erofs_maprecorder *m,
else
return -EOPNOTSUPP;
+ /* it doesn't equal to roundup(..) */
+ m->nextpackoff = rounddown(pos, vcnt << amortizedshift) +
+ (vcnt << amortizedshift);
big_pcluster = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1;
encodebits = ((vcnt << amortizedshift) - sizeof(__le32)) * 8 / vcnt;
+ eofs = erofs_blkoff(pos);
base = round_down(eofs, vcnt << amortizedshift);
in = m->kaddr + base;
@@ -399,8 +433,7 @@ static int compacted_load_cluster_from_disk(struct z_erofs_maprecorder *m,
err = z_erofs_reload_indexes(m, erofs_blknr(pos));
if (err)
return err;
- return unpack_compacted_index(m, amortizedshift, erofs_blkoff(pos),
- lookahead);
+ return unpack_compacted_index(m, amortizedshift, pos, lookahead);
}
static int z_erofs_load_cluster_from_disk(struct z_erofs_maprecorder *m,
@@ -583,11 +616,12 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m)
return 0;
}
-int z_erofs_map_blocks_iter(struct inode *inode,
- struct erofs_map_blocks *map,
- int flags)
+static int z_erofs_do_map_blocks(struct inode *inode,
+ struct erofs_map_blocks *map,
+ int flags)
{
struct erofs_inode *const vi = EROFS_I(inode);
+ bool ztailpacking = vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER;
struct z_erofs_maprecorder m = {
.inode = inode,
.map = map,
@@ -597,22 +631,8 @@ int z_erofs_map_blocks_iter(struct inode *inode,
unsigned long initial_lcn;
unsigned long long ofs, end;
- trace_z_erofs_map_blocks_iter_enter(inode, map, flags);
-
- /* when trying to read beyond EOF, leave it unmapped */
- if (map->m_la >= inode->i_size) {
- map->m_llen = map->m_la + 1 - inode->i_size;
- map->m_la = inode->i_size;
- map->m_flags = 0;
- goto out;
- }
-
- err = z_erofs_fill_inode_lazy(inode);
- if (err)
- goto out;
-
lclusterbits = vi->z_logical_clusterbits;
- ofs = map->m_la;
+ ofs = flags & EROFS_GET_BLOCKS_FINDTAIL ? inode->i_size - 1 : map->m_la;
initial_lcn = ofs >> lclusterbits;
endoff = ofs & ((1 << lclusterbits) - 1);
@@ -620,6 +640,9 @@ int z_erofs_map_blocks_iter(struct inode *inode,
if (err)
goto unmap_out;
+ if (ztailpacking && (flags & EROFS_GET_BLOCKS_FINDTAIL))
+ vi->z_idataoff = m.nextpackoff;
+
map->m_flags = EROFS_MAP_MAPPED | EROFS_MAP_ENCODED;
end = (m.lcn + 1ULL) << lclusterbits;
@@ -658,12 +681,20 @@ int z_erofs_map_blocks_iter(struct inode *inode,
goto unmap_out;
}
- map->m_llen = end - map->m_la;
- map->m_pa = blknr_to_addr(m.pblk);
+ if (flags & EROFS_GET_BLOCKS_FINDTAIL)
+ vi->z_idata_headlcn = m.lcn;
- err = z_erofs_get_extent_compressedlen(&m, initial_lcn);
- if (err)
- goto out;
+ map->m_llen = end - map->m_la;
+ if (ztailpacking && m.lcn == vi->z_idata_headlcn) {
+ map->m_flags |= EROFS_MAP_META;
+ map->m_pa = vi->z_idataoff;
+ map->m_plen = vi->z_idata_size;
+ } else {
+ map->m_pa = blknr_to_addr(m.pblk);
+ err = z_erofs_get_extent_compressedlen(&m, initial_lcn);
+ if (err)
+ goto out;
+ }
if (m.headtype == Z_EROFS_VLE_CLUSTER_TYPE_PLAIN)
map->m_algorithmformat = Z_EROFS_COMPRESSION_SHIFTED;
@@ -689,6 +720,31 @@ int z_erofs_map_blocks_iter(struct inode *inode,
__func__, map->m_la, map->m_pa,
map->m_llen, map->m_plen, map->m_flags);
+ return err;
+}
+
+int z_erofs_map_blocks_iter(struct inode *inode,
+ struct erofs_map_blocks *map,
+ int flags)
+{
+ int err = 0;
+
+ trace_z_erofs_map_blocks_iter_enter(inode, map, flags);
+
+ /* when trying to read beyond EOF, leave it unmapped */
+ if (map->m_la >= inode->i_size) {
+ map->m_llen = map->m_la + 1 - inode->i_size;
+ map->m_la = inode->i_size;
+ map->m_flags = 0;
+ goto out;
+ }
+
+ err = z_erofs_fill_inode_lazy(inode);
+ if (err)
+ goto out;
+
+ err = z_erofs_do_map_blocks(inode, map, flags);
+out:
trace_z_erofs_map_blocks_iter_exit(inode, map, flags, err);
/* aggressively BUG_ON iff CONFIG_EROFS_FS_DEBUG is on */
--
2.24.4