Learn to read. Linux has never allowed that. Most of the Unix systems do not allow that. Original _did_ allow that, but at the cost of very easily triggered fs corruption (and it didn't have things like rename(2) - it _did_ have userland implementation, of course, in suid-root mv(1), but that sucker had been extremely racy and could be easily used to screw filesystem to hell and back; adding rename(2) to the set of primitives combined with multiple links to directories leads to very nasty issues ...

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> diff --git a/drivers/block/dst/kst.c b/drivers/block/dst/kst.c new file mode 100644 index 0000000..b0608c9 --- /dev/null +++ b/drivers/block/dst/kst.c @@ -0,0 +1,1606 @@ +/* + * 2007+ Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru> + * All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Softwa...

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> diff --git a/drivers/block/Makefile b/drivers/block/Makefile index dd88e33..fcf042d 100644 --- a/drivers/block/Makefile +++ b/drivers/block/Makefile @@ -29,3 +29,4 @@ obj-$(CONFIG_VIODASD) += viodasd.o obj-$(CONFIG_BLK_DEV_SX8) += sx8.o obj-$(CONFIG_BLK_DEV_UB) += ub.o +obj-$(CONFIG_DST) += dst/ diff --git a/drivers/block/dst/Kconfig b/drivers/block/dst/Kconfig new file mode 100644 index 0000000..5bb9de8 --- /dev/null +++ b/dr...

Hello, Let's say we have an archive file "hello.zip" with a hello world program source code. We want to do this: cat hello.zip^/hello.c gcc hello.zip^/hello.c -o hello etc.. The '^' is an escape character and it tells the computer to treat the file as a directory. [Note: We can't do "cat hello.zip/hello.c" because of http://lwn.net/Articles/100148/ ] The kernel patch implements only a redirection of the request to another directory ("shadow directory") where a FUSE server must be mounted. Th...

Yes, that's exactly what RheaVFS and AVFS do. Except that they both use an escape character because: 1. without it some programs may break [ http://lwn.net/Articles/100148/ ] 2. it's very useful to pass additional parameters after the escape char to the server. We can start VFS servers (mentioned above) and chroot the whole user session into the mount directory of the server. It works but it's very slow, practically unusable. So both servers need some kind of VFS redirector. In the past there were...

Good point, I'll look onto it. A minor implementation problem with chrooted environment is that the FUSE VFS server must be run with root privileges to allow setuid programs on the mounted filesystems. But it's certainly doable. -- "Elves and Dragons!" I says to him. "Cabbages and potatoes are better for you and me." -- J. R. R. Tolkien -

Wouldn't you do this as a user space filesystem? -

On third thoughts, what's the reason for this? -

Procfs interface: /proc/<pid>/status, /proc/<pid>/{root-shdw, cwd-shdw}. Signed-off-by: Jaroslav Sykora <jaroslav.sykora@gmail.com> fs/proc/array.c | 23 +++++++++++++++++++ fs/proc/base.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 76 insertions(+) --- orig/fs/proc/base.c 2007-10-07 19:00:20.000000000 +0200 +++ new/fs/proc/base.c 2007-10-07 13:39:08.000000000 +0200 @@ -171,6 +171,32 @@ static int proc_cwd_link(struct inode *i return result; ...

Implements two stage lookup with escape character filtering and system calls for i386. Changes lookup path, namely do_path_lookup. This function is split into path_lookup_norm(), which performs standard name lookup, and path_lookup_shdw(), which performs name lookup in an associated shadow directory. Signed-off-by: Jaroslav Sykora <jaroslav.sykora@gmail.com> arch/i386/kernel/syscall_table.S | 6 fs/exec.c | 4 fs/file_table.c | 19 fs/na...