Re: [9fans] ext2srv ?

Re: [9fans] ext2srv ?

[Russ Cox]

ext2srv is in /sys/lib/pcdist/cmd.  i'm not convinced
of its reliability enough to run it in read-write
mode, but that's just because it's been so long since
i ran it.  for the distribution, i had to update one
piece of on-disk data structure, and that scared me.
specifically, the file name length has apparently
always been a byte followed by an unused (zero) byte.
ext2srv was reading the length as a short.  apparently
the unused byte is now used, but i and ext2srv don't
know what for.

the installation runs ext2srv -r so that ext2srv opens
the linux partition in read-only mode.

russ

Re: [9fans] ext2srv ?

[Alexander Viro]

On Tue, 14 Aug 2001, Russ Cox wrote:

> ext2srv is in /sys/lib/pcdist/cmd.  i'm not convinced
> of its reliability enough to run it in read-write
> mode, but that's just because it's been so long since
> i ran it.  for the distribution, i had to update one
> piece of on-disk data structure, and that scared me.
> specifically, the file name length has apparently
> always been a byte followed by an unused (zero) byte.
> ext2srv was reading the length as a short.  apparently
> the unused byte is now used, but i and ext2srv don't
> know what for.

It's a cached file type (for getdents(2)).

enum {
	S_SHIFT = 12	/* mode bits */
};
static unsigned char ext2_type_by_mode[S_IFMT >> S_SHIFT] = {
        [S_IFREG >> S_SHIFT]    EXT2_FT_REG_FILE,
        [S_IFDIR >> S_SHIFT]    EXT2_FT_DIR,
        [S_IFCHR >> S_SHIFT]    EXT2_FT_CHRDEV,
        [S_IFBLK >> S_SHIFT]    EXT2_FT_BLKDEV,
        [S_IFIFO >> S_SHIFT]    EXT2_FT_FIFO,
        [S_IFSOCK >> S_SHIFT]   EXT2_FT_SOCK,
        [S_IFLNK >> S_SHIFT]    EXT2_FT_SYMLINK,
};

and that byte will be ext2_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT]

ext2 superblock has a 32-bit bitmap (->s_feature_incompat). If ->s_rev_level
is 0 or bit 1 in ->s_feature_incompat (little-endian) is not set - leave
that byte zero. Otherwise set it as above.

BTW, you might want to check ext2 in recent tree - it got more readable
than it used to be.

Re: [9fans] ext2srv ?

[pac]

Ext2srv compiled fine. It runs, however, it did not create /n/linux, or something like. Here is what i did:

term% disk/kfscmd 'create /n/linux sys sys 755 d'
term%  ls -l /n
d-r-xr-xr-x M 3 sys sys 0 Mar 27 21:10 /n/9fat
d-r-xr-xr-x M 3 sys sys 0 Mar 27 21:10 /n/a:
d-rwxrwxr-x M 3 sys sys 0 Mar 27 21:10 /n/boot
d-r-xr-xr-x M 3 sys sys 0 Mar 27 21:10 /n/c:
d-r-xr-xr-x M 3 sys sys 0 Mar 27 21:10 /n/d:
d-rwxrwxr-x M 3 sys sys 0 Mar 27 21:10 /n/ftp
d-r-xr-xr-x M 3 sys sys 0 Mar 27 21:10 /n/kfs
d-rwxrwxr-x M 3 sys sys 0 Mar 27 21:10 /n/kremvax
d-rwxr-xr-x M 3 sys sys 0 Aug 15 10:22 /n/linux
d-rwxrwxr-x M 3 sys sys 0 Mar 27 21:10 /n/sid
d-rwxrwxr-x M 3 sys sys 0 Mar 27 21:10 /n/tapefs
d-rwxrwxr-x M 3 sys sys 0 Mar 27 21:10 /n/temp
d-r-xr-xr-x M 3 sys sys 0 Mar 27 21:10 /n/termrc.tmp

mount  -c /srv/ext2 /n/linux /dev/sdC0/linux
unmount: not mounted

/dev/sdC0/linux exists, but I am not able to mount the filesystem. What am I doing wrong?

Sorry for being such an ignorant. TIA, cheers,
Peter.

--
Peter A Cejchan
biologist
Acad. Sci., Prague, CZ
<cej at cejchan dot gli dot cas dot cz>

[9fans] ext2srv ?

[pac]

Hi all there,

I noticed that installation disk uses ext2srv

	ext2srv 378: serving #s/ext2

However, I am not able to find anything like ext2srv under /bin/* I found an ext2srv-0.2 package on the www,
but it was intended for Release 2 and did not compile on my R3.

So, is there any ext2 server around, or should I use an ftp to another box to transfer files between my Plan 9 and Linux partitions
(I still do much work under Linux ... :-(((  ?

TIA, cheers, Peter.


--
Peter A Cejchan
biologist
Acad. Sci., Prague, CZ
<cej at cejchan dot gli dot cas dot cz>