ref: e5f9915142d9e34a015fa4e184ab7331aad412da
parent: e5fae21d7c28103cbd4d5414538f18a448a60766
author: 9ferno <gophone2015@gmail.com>
date: Thu Dec 1 13:52:42 EST 2022
updated document
--- a/dat.h
+++ b/dat.h
@@ -144,7 +144,6 @@
u8 unused; /* for alignment and future use */
u16 len;
u64 dblkno; /* block number of the directory entry */
- // u64 path; /* same as qid.path */
};
#pragma pack off
--- a/docs/mafs.ms
+++ b/docs/mafs.ms
@@ -110,7 +110,7 @@
Tfree = 0, /* free block */
Tnone = 0,
Tdata, /* actual file contents */
- Tdentry, /* directory entry, size = Dentrysize */
+ Tdentry, /* directory entry, size = Dentrysize */
/* Tdata & indirect blocks are last, to allow for greater depth */
Tind0, /* contains a list of Tdata block numbers for files
and Tdentry block numbers for directories.*/
@@ -120,7 +120,7 @@
Tind4, /* contains a list of Tind1 block numbers */
/* gap for more indirect block depth in future.
It can be put upto Tind7 without needing any code changes */
- Maxtind, /* should be Tind0+Niblock */
+ Maxtind, /* should be Tind0+Niblock */
MAXTAG = Maxtind,
Tmaxind = Maxtind - 1,
@@ -142,8 +142,7 @@
.sp
A directory entry is defined as:
.nf
-enum {- Blocksize = 512ULL, /* minimum data unit size */
+enum { Blocksize = 512ULL, /* minimum data unit size */Metadataunits = 2,
Metadatablocksize = Metadataunits*Blocksize, /* Keep the original and a copy together */
@@ -150,10 +149,12 @@
Maxdatablockunits = 2048,
Nindperblock= (Blocksize-3*sizeof(u64))/sizeof(u64),/* number of pointers per block */
+ Nu64perblock= (Blocksize/sizeof(u64)), /* number of u64's in a block */
+ Dpathidx = (Blocksize/sizeof(u64) -1), /* index of path in the last data block, last u64 */
Namelen = 127, /* maximum length of a file name, calculated manually */
Ndblock = 32, /* number of direct blocks in a Dentry */
- Niblock = 5, /* maximum depth of indirect blocks, can increase it to 8 without issues */
+ Niblock = 5, /* maximum depth of indirect blocks, can increase it to 8 without issues */
};
struct Dentryhdr
{@@ -165,11 +166,11 @@
u64 size; /* 0 for directories. For files, size in bytes of the content - 16 */
u64 pdblkno; /* block number of the parent directory entry. Will be 0 for root. - 24 */
u64 pqpath; /* parent path - 32 */
- u64 mtime; /* modified time in nano seconds from epoch - 40 */
- u64 qpath; /* unique identifier Qid.path 48 */
+ u64 mtime; /* modified time in nano seconds from epoch - 40 */
+ u64 qpath; /* unique identifier Qid.path 48 */
u32 version; /* Qid.version 52 */
- u32 mode; /* same bits as defined in /sys/include/libc.h:/Dir\.mode/ - 56 */
- u8 namelen; /* store name as a counted string 57 */
+ u32 mode; /* same bits as defined in /sys/include/libc.h:/Dir\.mode/ - 56 */
+ u8 namelen; /* store name as a counted string 57 */
s8 name[Namelen]; /* Namelen = 127 - 184*/
};
struct Datahdr
@@ -178,7 +179,6 @@
u8 unused; /* for alignment and future use */
u16 len;
u64 dblkno; /* block number of the directory entry */
- u64 path; /* same as path */
};
enum {@@ -197,8 +197,8 @@
struct
{u64 dblocks[Ndblock]; /* direct blocks. */
- /* List of Tdata block numbers for files and
- Tdentry block numbers for directories */
+ /* List of Tdata block numbers for files and
+ Tdentry block numbers for directories */
u64 iblocks[Niblock]; /* indirect blocks */
};
Super;
@@ -206,16 +206,16 @@
/* when size <= Dentrysize-184-sizeof(Tag), store the data here itself */
s8 buf[Ddatasize];
};
- u64 path; /* same as path */
+ u64 path; /* same as qid.path */
};
struct Indirect
{- u8 tagi; /* the suffix i to avoid union complaining about ambiguous fields */
+ u8 tagi; /* the suffix i to avoid union complaining about ambiguous fields */
u8 veri;
- u8 pad[6]; /* unused, to align to a multiple of 8 */
+ u8 pad[6]; /* unused, to align to a multiple of 8 */
u64 dblkno; /* block number of the directory entry */
u64 bufa[Nindperblock];
- u64 path; /* same as path */
+ u64 path; /* same as qid.path */
};
struct Metadataunit
{@@ -252,28 +252,29 @@
Blocksize 512 Metadataunits 2 Maxdatablockunits 2048
Dentryhdr size 184 Ddatasize 320
Dentry size 512 Namelen 127
+ Datahdr size 12 Ddataidssize 20 Maxdatablocksize 1048556
Namelen 127 Ndblock 32 Niblock 5
- Nindperblock 61 Maxdatablocksize 1048548
- A Tind0 unit points to 1 data blocks (1048548 bytes)
+ Nindperblock 61 Maxdatablocksize 1048556
+ A Tind0 unit points to 1 data blocks (1048556 bytes)
block points to 61 data blocks
reli start 32 max 92
- max size 93*Maxdatablocksize = 97514964 bytes = 92 MiB
- A Tind1 unit points to 61 data blocks (63961428 bytes)
+ max size 93*Maxdatablocksize = 97515708 bytes = 92 MiB
+ A Tind1 unit points to 61 data blocks (63961916 bytes)
block points to 3721 data blocks
reli start 93 max 3813
- max size 3814*Maxdatablocksize = 3999162072 bytes = 3 GiB
- A Tind2 unit points to 3721 data blocks (3901647108 bytes)
+ max size 3814*Maxdatablocksize = 3999192584 bytes = 3 GiB
+ A Tind2 unit points to 3721 data blocks (3901676876 bytes)
block points to 226981 data blocks
reli start 3814 max 230794
- max size 230795*Maxdatablocksize = 241999635660 bytes = 225 GiB
- A Tind3 unit points to 226981 data blocks (238000473588 bytes)
+ max size 230795*Maxdatablocksize = 242001482020 bytes = 225 GiB
+ A Tind3 unit points to 226981 data blocks (238002289436 bytes)
block points to 13845841 data blocks
reli start 230795 max 14076635
- max size 14076636*Maxdatablocksize = 14760028524528 bytes = 13 TiB
- A Tind4 unit points to 13845841 data blocks (14518028888868 bytes)
+ max size 14076636*Maxdatablocksize = 14760141137616 bytes = 13 TiB
+ A Tind4 unit points to 13845841 data blocks (14518139655596 bytes)
block points to 844596301 data blocks
reli start 14076636 max 858672936
- max size 858672937*Maxdatablocksize = 900359790745476 bytes = 818 TiB
+ max size 858672937*Maxdatablocksize = 900366660128972 bytes = 818 TiB
.fi
.ne 30
.sp
@@ -372,8 +373,8 @@
box height fieldht invis "version 0"
box height fieldht invis "path 66"
box height fieldht invis "size 0"
- box height fieldht invis "pdblkno 10"
- box height fieldht invis "pqpath 10"
+ box height fieldht invis "pdblkno 20"
+ box height fieldht invis "pqpath 20"
box height fieldht invis "mtime 1653302180819962729"
box height fieldht invis "mode 20000000777"
box height fieldht invis "uid 10006"
@@ -403,7 +404,7 @@
box height fieldht invis "version 0"
box height fieldht invis "path 67"
box height fieldht invis "size 5"
- box height fieldht invis "pdblkno 13"
+ box height fieldht invis "pdblkno 26"
box height fieldht invis "pqpath 66"
box height fieldht invis "mtime 1653302180823455071"
box height fieldht invis "mode 666"
@@ -424,7 +425,7 @@
box height fieldht invis "version 0"
box height fieldht invis "path 68"
box height fieldht invis "size 5"
- box height fieldht invis "pdblkno 13"
+ box height fieldht invis "pdblkno 26"
box height fieldht invis "pqpath 66"
box height fieldht invis "mtime 1653302180823455071"
box height fieldht invis "mode 666"
@@ -486,7 +487,7 @@
box height fieldht invis "version 0"
box height fieldht invis "path 70"
box height fieldht invis "size 2056192"
- box height fieldht invis "pdblkno 16"
+ box height fieldht invis "pdblkno 32"
box height fieldht invis "pqpath 69"
box height fieldht invis "mtime 1653302180819962729"
box height fieldht invis "mode 20000000777"
@@ -495,7 +496,7 @@
box height fieldht invis "muid 10006"
box height fieldht invis "direct blocks"
box height fieldht invis " 0 36"
- box height fieldht invis " 1 41000"
+ box height fieldht invis " 1 2084"
box height fieldht invis " 2 0"
box height fieldht invis "."
box height fieldht invis "."
@@ -503,7 +504,7 @@
box height fieldht invis " 0 0"
box height fieldht invis " 1 0"
box height fieldht invis " 2 0"
- "Block 35 contents" at Bound.nw + 0,0.1i ljust
+ "Block 34 contents" at Bound.nw + 0,0.1i ljust
"Representation of a 2 MiB file (/dir3/2MB.file)" ljust at Bound.n + 0,0.3i
}
move 4*boxwid
@@ -523,7 +524,7 @@
down
{ Bound: box height 9*bigboxht width 3.3*boxwid }move 0.1i
- box height fieldht invis "Tdentry 64 104"
+ box height fieldht invis "Tdentry 64 106"
box height fieldht invis "name big.file"
box height fieldht invis "version 0"
box height fieldht invis "path 64"
@@ -581,7 +582,7 @@
{ Bound: box height 3*bigboxht width 3.3*boxwid }move 0.1i
box height fieldht invis "Tdata 64 22 2048"
- box height fieldht invis "+06 0123456789"; {"more content" at last box.e + 1i,0 ljust}+ box height fieldht invis " 0123456789"; {"more content" at last box.e + 1i,0 ljust} box height fieldht invis "."; {"of big.file" at last box.e + 1i,0 ljust}box height fieldht invis "."
"Block 65560 contents" at Bound.nw + 0,0.1i ljust
@@ -632,9 +633,9 @@
l a a .
Block Description Backup Block
_
-1 /adm/config last block number -2
-2 /adm/super last block number -4
-10 / last block number -6
+2 /adm/config last block number -2
+4 /adm/super last block number -4
+20 / last block number -6
.TE
.ta 5n 10n 15n 20n 25n 30n 35n 40n 45n 50n 55n 60n 65n 70n 75n 80n
.sp
@@ -676,6 +677,7 @@
{Iobuf* link; /* least recently used Iobuf in the circular linked list */
QLock; /* controls access to this hash bucket */
+ u64 n; /* count of Iobuf's in the circular list */
};
struct Iobuf
{@@ -1078,7 +1080,7 @@
disk/free List the free blocks. It reads the contents of /adm/frees.
disk/used List the used blocks by traversing all directory entries.
disk/block Show the contents of a block.
-disk/unused Given a list of used blocks, lists the unused blocks.
+disk/unused Lists the unused blocks when given extents of used blocks.
disk/updatefrees Update the contents of /adm/frees.
.TE
.sp
@@ -1256,37 +1258,48 @@
.nf
diff <{disk/unused -l <{disk/used tests/test.0/disk} 32}} <{disk/free tests/test.0/disk}.fi
-.sp
-Changing the service name without a ream.
-.sp
-.nf
- disk/block /dev/sdF1/fs 1 | wc
- Tdata 2
- size 6001172505088
- nblocks 11721040049
- backup config 1 to 11721040048
- backup super 2 to 11721040046
- backup root 3 to 117210400464
- service mafs_ddf_1
-
- dd -if /dev/sdF1/fs -count 10 -skip 682 -bs 1
- mafs_ddf_110+0 records in
- 10+0 records out
-
- dd -if <{echo m_ddf_1; cat /dev/zero} -of /dev/sdF1/fs -count 11 -oseek 682 -bs 1- 7+0 records in
- 7+0 records out
-
- disk/block /dev/sdF1/fs 1
- Tdata 2
- size 6001172505088
- nblocks 11721040049
- backup config 1 to 11721040048
- backup super 2 to 11721040046
- backup root 3 to 11721040044
- service m_ddf_1
-.fi
\".sp
+\"Changing the service name without a ream.
+\".sp
+\".nf
+\" disk/block /dev/sdF1/fs 2 | wc
+\" Tdentry 2 2
+\" name config
+\" uid -1
+\" gid -1
+\" muid -1
+\" size 146
+\" pdblkno 6
+\" pqpath 6
+\" mtime 1669916563259999461
+\" path 2
+\" version 0
+\" mode 444
+\" size 6001172505088
+\" nblocks 11721040049
+\" backup config 2 to 11721040047
+\" backup super 4 to 11721040045
+\" backup root 20 to 11721040043
+\" service m_ddf_1
+\"
+\" dd -if /dev/sdF1/fs -count 10 -skip 682 -bs 1
+\" mafs_ddf_110+0 records in
+\" 10+0 records out
+\"
+\" dd -if <{echo m_ddf_1; cat /dev/zero} -of /dev/sdF1/fs -count 11 -oseek 682 -bs 1+\" 7+0 records in
+\" 7+0 records out
+\"
+\" disk/block /dev/sdF1/fs 1
+\" Tdata 2
+\" size 6001172505088
+\" nblocks 11721040049
+\" backup config 1 to 11721040048
+\" backup super 2 to 11721040046
+\" backup root 3 to 11721040044
+\" service m_ddf_1
+\".fi
+\".sp
\"Changing the magic phrase in the magic block. - the offsets and the block output format has changed.
\".sp
\".nf
@@ -1332,6 +1345,7 @@
tests/regress.rc All regression tests
tests/chkextents.rc Unit tests on extents
tests/chkreli.rc Unit tests on relative index lookups
+tests/chknlastdatablocks.rc Unit tests on the number of blocks in the last Tdata block
_
tests/6.offsets Write file using different offsets to test mafswrite()
tests/6.sizes Show the effects of the different parameters