[RFC PATCH v2 1/3] erofs-utils: lib: add support for fragments data decompression
Yue Hu
zbestahu at gmail.com
Sat Jul 23 17:17:13 AEST 2022
Add compressed fragments support for erofsfuse.
Signed-off-by: Yue Hu <huyue2 at coolpad.com>
---
include/erofs/internal.h | 13 +++++++++++
include/erofs_fs.h | 19 +++++++++++----
lib/data.c | 50 ++++++++++++++++++++++++++++++++++++++--
lib/zmap.c | 18 ++++++++++++---
4 files changed, 90 insertions(+), 10 deletions(-)
diff --git a/include/erofs/internal.h b/include/erofs/internal.h
index 48498fe..ce235de 100644
--- a/include/erofs/internal.h
+++ b/include/erofs/internal.h
@@ -102,6 +102,7 @@ struct erofs_sb_info {
u16 devt_slotoff; /* used for mkfs */
u16 device_id_mask; /* used for others */
};
+ struct erofs_inode *fragments_inode;
};
/* global sbi */
@@ -132,6 +133,7 @@ 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(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
+EROFS_FEATURE_FUNCS(fragments, incompat, INCOMPAT_FRAGMENTS)
EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
#define EROFS_I_EA_INITED (1 << 0)
@@ -190,6 +192,8 @@ struct erofs_inode {
void *eof_tailraw;
unsigned int eof_tailrawsize;
+ erofs_off_t fragmentoff;
+
union {
void *compressmeta;
void *chunkindexes;
@@ -201,6 +205,7 @@ struct erofs_inode {
uint64_t z_tailextent_headlcn;
unsigned int z_idataoff;
#define z_idata_size idata_size
+#define z_fragmentoff fragmentoff
};
};
#ifdef WITH_ANDROID
@@ -208,6 +213,11 @@ struct erofs_inode {
#endif
};
+static inline erofs_off_t z_erofs_map_header_pos(struct erofs_inode *vi)
+{
+ return round_up(iloc(vi->nid) + vi->inode_isize + vi->xattr_isize, 8);
+}
+
static inline bool is_inode_layout_compression(struct erofs_inode *inode)
{
return erofs_inode_is_data_compressed(inode->datalayout);
@@ -276,6 +286,7 @@ enum {
BH_Mapped,
BH_Encoded,
BH_FullMapped,
+ BH_Fragments,
};
/* Has a disk mapping */
@@ -286,6 +297,8 @@ enum {
#define EROFS_MAP_ENCODED (1 << BH_Encoded)
/* The length of extent is full */
#define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped)
+/* Located in fragments */
+#define EROFS_MAP_FRAGMENTS (1 << BH_Fragments)
struct erofs_map_blocks {
char mpage[EROFS_BLKSIZ];
diff --git a/include/erofs_fs.h b/include/erofs_fs.h
index 08f9761..d957ebb 100644
--- a/include/erofs_fs.h
+++ b/include/erofs_fs.h
@@ -25,13 +25,15 @@
#define EROFS_FEATURE_INCOMPAT_CHUNKED_FILE 0x00000004
#define EROFS_FEATURE_INCOMPAT_DEVICE_TABLE 0x00000008
#define EROFS_FEATURE_INCOMPAT_ZTAILPACKING 0x00000010
+#define EROFS_FEATURE_INCOMPAT_FRAGMENTS 0x00000020
#define EROFS_ALL_FEATURE_INCOMPAT \
(EROFS_FEATURE_INCOMPAT_LZ4_0PADDING | \
EROFS_FEATURE_INCOMPAT_COMPR_CFGS | \
EROFS_FEATURE_INCOMPAT_BIG_PCLUSTER | \
EROFS_FEATURE_INCOMPAT_CHUNKED_FILE | \
EROFS_FEATURE_INCOMPAT_DEVICE_TABLE | \
- EROFS_FEATURE_INCOMPAT_ZTAILPACKING)
+ EROFS_FEATURE_INCOMPAT_ZTAILPACKING | \
+ EROFS_FEATURE_INCOMPAT_FRAGMENTS)
#define EROFS_SB_EXTSLOT_SIZE 16
@@ -294,16 +296,21 @@ struct z_erofs_lzma_cfgs {
* 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)
+ * bit 4 : fragment 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
+#define Z_EROFS_ADVISE_FRAGMENT_PCLUSTER 0x0010
struct z_erofs_map_header {
- __le16 h_reserved1;
- /* record the size of tailpacking data */
- __le16 h_idata_size;
+ union {
+ /* direct addressing for fragment offset */
+ __le32 h_fragmentoff;
+ /* record the size of tailpacking data */
+ __le16 h_idata_size;
+ };
__le16 h_advise;
/*
* bit 0-3 : algorithm type of head 1 (logical cluster type 01);
@@ -312,12 +319,14 @@ struct z_erofs_map_header {
__u8 h_algorithmtype;
/*
* bit 0-2 : logical cluster bits - 12, e.g. 0 for 4096;
- * bit 3-7 : reserved.
+ * bit 3-6 : reserved;
+ * bit 7 : merge the whole file into fragments or not.
*/
__u8 h_clusterbits;
};
#define Z_EROFS_VLE_LEGACY_HEADER_PADDING 8
+#define Z_EROFS_FRAGMENT_INODE_BIT 7
/*
* Fixed-sized output compression ondisk Logical Extent cluster type:
diff --git a/lib/data.c b/lib/data.c
index 6bc554d..2f3ebb8 100644
--- a/lib/data.c
+++ b/lib/data.c
@@ -217,8 +217,8 @@ static int erofs_read_raw_data(struct erofs_inode *inode, char *buffer,
return 0;
}
-static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
- erofs_off_t size, erofs_off_t offset)
+static int z_erofs_do_read_data(struct erofs_inode *inode, char *buffer,
+ erofs_off_t size, erofs_off_t offset)
{
erofs_off_t end, length, skip;
struct erofs_map_blocks map = {
@@ -275,6 +275,27 @@ static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
continue;
}
+ if (map.m_flags & EROFS_MAP_FRAGMENTS) {
+ char *out;
+
+ out = malloc(length);
+ if (!out) {
+ ret = -ENOMEM;
+ break;
+ }
+ ret = z_erofs_do_read_data(sbi.fragments_inode, out,
+ length,
+ inode->z_fragmentoff);
+ if (ret < 0) {
+ free(out);
+ break;
+ }
+ memcpy(buffer + end - offset, out + skip, length -
+ skip);
+ free(out);
+ continue;
+ }
+
if (map.m_plen > bufsize) {
bufsize = map.m_plen;
raw = realloc(raw, bufsize);
@@ -304,6 +325,31 @@ static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
return ret < 0 ? ret : 0;
}
+static int z_erofs_read_data(struct erofs_inode *inode, char *buffer,
+ erofs_off_t size, erofs_off_t offset)
+{
+ struct erofs_inode *vi = inode;
+
+ if (erofs_sb_has_fragments()) {
+ int ret;
+ struct z_erofs_map_header *h;
+ char buf[sizeof(struct z_erofs_map_header)];
+
+ ret = dev_read(0, buf, z_erofs_map_header_pos(inode),
+ sizeof(buf));
+ if (ret < 0)
+ return -EIO;
+
+ h = (struct z_erofs_map_header *)buf;
+
+ if (h->h_clusterbits >> Z_EROFS_FRAGMENT_INODE_BIT) {
+ vi = sbi.fragments_inode;
+ offset += le32_to_cpu(h->h_fragmentoff);
+ }
+ }
+ return z_erofs_do_read_data(vi, buffer, size, offset);
+}
+
int erofs_pread(struct erofs_inode *inode, char *buf,
erofs_off_t count, erofs_off_t offset)
{
diff --git a/lib/zmap.c b/lib/zmap.c
index 95745c5..812bf32 100644
--- a/lib/zmap.c
+++ b/lib/zmap.c
@@ -32,7 +32,6 @@ int z_erofs_fill_inode(struct erofs_inode *vi)
static int z_erofs_fill_inode_lazy(struct erofs_inode *vi)
{
int ret;
- erofs_off_t pos;
struct z_erofs_map_header *h;
char buf[sizeof(struct z_erofs_map_header)];
@@ -42,9 +41,8 @@ static int z_erofs_fill_inode_lazy(struct erofs_inode *vi)
DBG_BUGON(!erofs_sb_has_big_pcluster() &&
!erofs_sb_has_ztailpacking() &&
vi->datalayout == EROFS_INODE_FLAT_COMPRESSION_LEGACY);
- pos = round_up(iloc(vi->nid) + vi->inode_isize + vi->xattr_isize, 8);
- ret = dev_read(0, buf, pos, sizeof(buf));
+ ret = dev_read(0, buf, z_erofs_map_header_pos(vi), sizeof(buf));
if (ret < 0)
return -EIO;
@@ -83,6 +81,17 @@ static int z_erofs_fill_inode_lazy(struct erofs_inode *vi)
if (ret < 0)
return ret;
}
+ if (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER) {
+ struct erofs_map_blocks map = { .index = UINT_MAX };
+
+ ret = z_erofs_do_map_blocks(vi, &map,
+ EROFS_GET_BLOCKS_FINDTAIL);
+ if (ret < 0) {
+ erofs_err("failed to find tail for fragment pcluster");
+ return ret;
+ }
+ vi->z_fragmentoff = le32_to_cpu(h->h_fragmentoff);
+ }
vi->flags |= EROFS_I_Z_INITED;
return 0;
}
@@ -546,6 +555,7 @@ static int z_erofs_do_map_blocks(struct erofs_inode *vi,
int flags)
{
bool ztailpacking = vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER;
+ bool in_fragments = vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER;
struct z_erofs_maprecorder m = {
.inode = vi,
.map = map,
@@ -609,6 +619,8 @@ static int z_erofs_do_map_blocks(struct erofs_inode *vi,
map->m_flags |= EROFS_MAP_META;
map->m_pa = vi->z_idataoff;
map->m_plen = vi->z_idata_size;
+ } else if (in_fragments && m.lcn == vi->z_tailextent_headlcn) {
+ map->m_flags |= EROFS_MAP_FRAGMENTS;
} else {
map->m_pa = blknr_to_addr(m.pblk);
err = z_erofs_get_extent_compressedlen(&m, initial_lcn);
--
2.17.1
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