code: 9ferno

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not storing data in Dentry to avoid complexity

It is simpler to have 2 Dentries of 250 bytes each per block
instead of having 500 bytes of Dentry per block with data

--- a/appl/cmd/disk/kfs64.b

+++ b/appl/cmd/disk/kfs64.b

@@ -8,10 +8,8 @@

 # Differences from kfs

 #	updating all file offsets, sizes and block numbers to 64 bits

 #	triple, quadruple, quintiple and sextuple-indirect blocks

-#	filename size 228 bytes TODO variable

-#	store 128 bytes of data in Dentry

+#	filename size 102 bytes

 #	using a default bufsize of 512 bytes, small but not too small

-#	as locks are per block, do not have to worry about locking out other files' access

 include "sys.m";

 	sys: Sys;

@@ -44,7 +42,7 @@

 #  fundamental constants

 #

 	# keeping Dentrysize to 512 and 128 bytes for data in Dentry leaves 228 bytes

-NAMELEN:	con 224; # ext2, ext3, ext4, zfs - 255 bytes

+NAMELEN:	con 102; # ext2, ext3, ext4, zfs - 255 bytes

 NDBLOCK:	con 8;	# number of direct blocks in Dentry

 NIBLOCK:	con 6;	# max depth of indirect blocks in Dentry - sextuple-indirect blocks

 MAXFILESIZE:	con big 16r7FFFFFFFFFFFFFFF;	# Plan 9's limit (kfs's size is signed)

@@ -206,6 +204,7 @@

 	uid:	int;

 	open:	int;

 	cons:	int;	# if opened by console

+		# d* fields for maintaining state while traversing directories

 	doffset: big;	# directory reading

 	dvers:	int;

 	daddr:	big;	# state for next read, different from kfs

@@ -373,7 +372,7 @@

 #	BUF = block in these variables

 RBUFSIZE	:= 512;				# block size, real block size

 BUFSIZE		:= 500; # RBUFSIZE-Tagsize; # usable block size

-DIRPERBUF	:= 1;				# number of Dentries per block

+DIRPERBUF	:= 2;				# number of Dentries per block

 INDPERBUF	:= big 62; # BUFSIZE/8; # number of pointers in a block

 	# number of blocks representable by a double indirect block of pointers

 INDPERBUF2	:= big 3844; # INDPERBUF*INDPERBUF;

@@ -1580,20 +1579,6 @@

 		if(d == nil)

 			return ferr(f, e, file, nil);

 	}

-	# read data in Dentry

-	if(offset < big Dentrydatasize){

-		if(offset + big count <= big Dentrydatasize){

-			nread = int offset+count;

-			data[0:] = d.buf[Odata+int offset:Odata+nread];

-			count -= nread;

-			offset += big nread;

-		}else{

-			nread = Dentrydatasize-int offset;

-			data[0:] = d.buf[Odata+int offset:Odata+Dentrydatasize];

-			count -= nread;

-			offset += big nread;

-		}

-	}

 	while(count > 0){

 		if(d.iob == nil){

 			# must check and reacquire entry

@@ -1601,11 +1586,11 @@

 			if(d == nil)

 				return ferr(f, e, file, nil);

 		}

-		addr := (offset-big Dentrydatasize) / big BUFSIZE;

+		addr := offset / big BUFSIZE;

 		if(addr == file.lastra+big 1)

 			;	# dbufread(p, d, addr+1);

 		file.lastra = addr;

-		o := int ((offset-big Dentrydatasize) % big BUFSIZE);

+		o := int (offset % big BUFSIZE);

 		n := BUFSIZE - o;

 		if(n > count)

 			n = count;

@@ -1668,26 +1653,6 @@

 	d.update();

 	nwrite := 0;

-	# write data to Dentry

-	if(d.iob == nil){

-		# must check and reacquire entry

-		(d, e) = Dentry.getd(file, Bread|Bmod);

-		if(d == nil)

-			return ferr(f, e, file, nil);

-	}

-	if(offset < big Dentrydatasize){

-		if(offset + big count <= big Dentrydatasize){

-			nwrite = int offset+count;

-			d.buf[Odata+int offset:] = f.data[0:nwrite];

-			count -= nwrite;

-			offset += big nwrite;

-		}else{

-			nwrite = Dentrydatasize-int offset;

-			d.buf[Odata+int offset:] = f.data[0:nwrite];

-			count -= nwrite;

-			offset += big nwrite;

-		}

-	}

 	while(count > 0){

 		if(d.iob == nil){

 			# must check and reacquire entry

@@ -1695,8 +1660,8 @@

 			if(d == nil)

 				return ferr(f, e, file, nil);

 		}

-		addr := (offset-big Dentrydatasize) / big BUFSIZE;

-		o := int ((offset-big Dentrydatasize) % big BUFSIZE);

+		addr := offset / big BUFSIZE;

+		o := int (offset % big BUFSIZE);

 		n := BUFSIZE - o;

 		if(n > count)

 			n = count;

@@ -1979,7 +1944,6 @@

 	# if rename,

 	# must have write permission in parent

-	# TODO if NAMELEN is variable, this has to be changed to a mv or cp for files

 	while(d.name != dir.name){

 		# drop entry to prevent deadlock, then

@@ -2282,8 +2246,8 @@

 #	u64	iblock[NIBLOCK];[8*6]	140

 #	u32	atime;					144

 #	u32	mtime;					148

-#	u8	name[NAMELEN];

-#	u8 data in Dentry size = 512 RBUFSIZE - 224 NAMELEN - 148 -Tagsize = 128

+#	u8	name[NAMELEN];	moved this to the end to make it easier to increase if need to

+#	Dentry size = (512 RBUFSIZE -Tagsize - 148 - 102 NAMELEN)/2= 250

 Ouid: con 0;

 Ogid: con Ouid+2;

@@ -2297,9 +2261,7 @@

 Oatime: con Oiblock+NIBLOCK*8;

 Omtime: con Oatime+4;

 Oname: con Omtime+4;

-Odata: con Oname+NAMELEN;

-Dentrydatasize: con 128;

-Dentrysize: con Odata+Dentrydatasize;	# should be 500 = BUFSIZE = RBUFSIZE - Tagsize

+Dentrysize: con Oname+NAMELEN; # kept to 250 = BUFSIZE/2 = (RBUFSIZE -Tagsize)/2

 Dentry.unpack(a: array of byte): ref Dentry

 {

@@ -2402,6 +2364,8 @@

 	}

 }

+# get the a'th block number

+#	when tag != 0, allocate a'th block if empty

 Dentry.getblk(d: self ref Dentry, a: big, tag: int): ref Iobuf

 {

 	addr := d.rel2abs(a, tag, 0);