[RFC PATCH v3 1/3] erofs-utils: lib: add support for fragments data decompression
Gao Xiang
xiang at kernel.org
Wed Aug 17 04:48:54 AEST 2022
Hi Yue,
I roughly look, some comments below...
On Wed, Aug 03, 2022 at 11:51:28AM +0800, Yue Hu wrote:
> Add compressed fragments support for erofsfuse.
>
> Signed-off-by: Yue Hu <huyue2 at coolpad.com>
> ---
> include/erofs/internal.h | 8 ++++++++
> include/erofs_fs.h | 26 ++++++++++++++++++++------
> lib/data.c | 20 ++++++++++++++++++++
> lib/super.c | 24 +++++++++++++++++++++++-
> lib/zmap.c | 26 ++++++++++++++++++++++++++
> 5 files changed, 97 insertions(+), 7 deletions(-)
>
> diff --git a/include/erofs/internal.h b/include/erofs/internal.h
> index 48498fe..5980db7 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 *frags_inode;
I rethought about this feature and the naming.
I think we could name the tail (or the whole file) as a fragment.
But I tend to name the special inode as "packed inode", since
this special inode can be used as "compressed metadata" as well.
So, just name as "packed_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;
move it to the end? or find a better place?
> +
> 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
drop this line?
> };
> };
> #ifdef WITH_ANDROID
> @@ -276,6 +281,7 @@ enum {
> BH_Mapped,
> BH_Encoded,
> BH_FullMapped,
> + BH_Fragments,
BH_Fragment,
> };
>
> /* Has a disk mapping */
> @@ -286,6 +292,8 @@ 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)
EROFS_MAP_FRAGMENT ?
>
> struct erofs_map_blocks {
> char mpage[EROFS_BLKSIZ];
> diff --git a/include/erofs_fs.h b/include/erofs_fs.h
> index 08f9761..4e13566 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
>
> @@ -73,7 +75,9 @@ struct erofs_super_block {
> } __packed u1;
> __le16 extra_devices; /* # of devices besides the primary device */
> __le16 devt_slotoff; /* startoff = devt_slotoff * devt_slotsize */
> - __u8 reserved2[38];
> + __u8 reserved[6];
> + __le64 frags_nid; /* nid of the special fragments inode */
packed_nid; ?
> + __u8 reserved2[24];
> };
>
> /*
> @@ -294,16 +298,24 @@ 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;
> + struct {
> + __le16 h_reserved1;
> + /* record the size of tailpacking data */
> + __le16 h_idata_size;
That is really somewhat a layout mistake when introducing
ztailpacking feature.
> + };
> + };
> __le16 h_advise;
> /*
> * bit 0-3 : algorithm type of head 1 (logical cluster type 01);
> @@ -312,12 +324,14 @@ 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.
Move the whole file into packed inode or not.
> */
> __u8 h_clusterbits;
> };
>
> #define Z_EROFS_VLE_LEGACY_HEADER_PADDING 8
> +#define Z_EROFS_FRAGMENT_INODE_BIT 7
Move this forward, just before "struct z_erofs_map_header"
> /*
> * Fixed-sized output compression ondisk Logical Extent cluster type:
> diff --git a/lib/data.c b/lib/data.c
> index 6bc554d..b9dd07b 100644
> --- a/lib/data.c
> +++ b/lib/data.c
> @@ -275,6 +275,26 @@ 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 - skip);
> + if (!out) {
> + ret = -ENOMEM;
> + break;
> + }
> + ret = z_erofs_read_data(sbi.frags_inode, out,
> + length - skip,
> + inode->z_fragmentoff + skip);
> + if (ret < 0) {
> + free(out);
> + break;
> + }
> + memcpy(buffer + end - offset, out, length - skip);
> + free(out);
> + continue;
> + }
> +
> if (map.m_plen > bufsize) {
> bufsize = map.m_plen;
> raw = realloc(raw, bufsize);
> diff --git a/lib/super.c b/lib/super.c
> index b267412..4d3ca00 100644
> --- a/lib/super.c
> +++ b/lib/super.c
> @@ -104,6 +104,21 @@ int erofs_read_superblock(void)
> sbi.xattr_blkaddr = le32_to_cpu(dsb->xattr_blkaddr);
> sbi.islotbits = EROFS_ISLOTBITS;
> sbi.root_nid = le16_to_cpu(dsb->root_nid);
> + sbi.frags_inode = NULL;
> + if (erofs_sb_has_fragments()) {
> + struct erofs_inode *inode;
> +
> + inode = calloc(1, sizeof(struct erofs_inode));
> + if (!inode)
> + return -ENOMEM;
> + inode->nid = le64_to_cpu(dsb->frags_nid);
> + ret = erofs_read_inode_from_disk(inode);
> + if (ret) {
> + free(inode);
> + return ret;
> + }
> + sbi.frags_inode = inode;
> + }
> sbi.inos = le64_to_cpu(dsb->inos);
> sbi.checksum = le32_to_cpu(dsb->checksum);
>
> @@ -111,11 +126,18 @@ int erofs_read_superblock(void)
> sbi.build_time_nsec = le32_to_cpu(dsb->build_time_nsec);
>
> memcpy(&sbi.uuid, dsb->uuid, sizeof(dsb->uuid));
> - return erofs_init_devices(&sbi, dsb);
> +
> + ret = erofs_init_devices(&sbi, dsb);
> + if (ret && sbi.frags_inode)
> + free(sbi.frags_inode);
> + return ret;
> }
>
> void erofs_put_super(void)
> {
> if (sbi.devs)
> free(sbi.devs);
> +
> + if (sbi.frags_inode)
> + free(sbi.frags_inode);
> }
> diff --git a/lib/zmap.c b/lib/zmap.c
> index 95745c5..16267ae 100644
> --- a/lib/zmap.c
> +++ b/lib/zmap.c
> @@ -83,6 +83,20 @@ 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) {
> + vi->z_fragmentoff = le32_to_cpu(h->h_fragmentoff);
> +
> + if (h->h_clusterbits >> Z_EROFS_FRAGMENT_INODE_BIT) {
> + vi->z_tailextent_headlcn = 0;
> + } else {
> + struct erofs_map_blocks map = { .index = UINT_MAX };
> +
> + ret = z_erofs_do_map_blocks(vi, &map,
> + EROFS_GET_BLOCKS_FINDTAIL);
> + if (ret < 0)
> + return ret;
> + }
> + }
> vi->flags |= EROFS_I_Z_INITED;
> return 0;
> }
> @@ -546,6 +560,7 @@ static int z_erofs_do_map_blocks(struct erofs_inode *vi,
> int flags)
> {
> bool ztailpacking = vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER;
> + bool infrags = vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER;
inpacked;
Thanks,
Gao Xiang
> struct z_erofs_maprecorder m = {
> .inode = vi,
> .map = map,
> @@ -609,6 +624,9 @@ 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 (infrags && m.lcn == vi->z_tailextent_headlcn) {
> + map->m_flags |= EROFS_MAP_FRAGMENTS;
> + DBG_BUGON(!map->m_la);
> } else {
> map->m_pa = blknr_to_addr(m.pblk);
> err = z_erofs_get_extent_compressedlen(&m, initial_lcn);
> @@ -652,6 +670,14 @@ int z_erofs_map_blocks_iter(struct erofs_inode *vi,
> if (err)
> goto out;
>
> + if ((vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER) &&
> + !vi->z_tailextent_headlcn) {
> + map->m_llen = map->m_la + 1;
> + map->m_la = 0;
> + map->m_flags = EROFS_MAP_MAPPED | EROFS_MAP_FRAGMENTS;
> + goto out;
> + }
> +
> err = z_erofs_do_map_blocks(vi, map, flags);
> out:
> DBG_BUGON(err < 0 && err != -ENOMEM);
> --
> 2.17.1
>
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