This patch provides basic protection against damage resulting from
differently compiled servers blindly copying tables to one another.
In every getsysinfo() call, the caller is provided with the expected
size of the requested data structure. The callee fails the call if
the expected size does not match the data structure's actual size.
This stops the printer driver from hanging the entire system when
/dev/lp is opened on systems that do not have a parallel port. With
this change, the printer driver shuts down immediately after loading
on such systems.
Using sendrec directly only results in problems. While it is not
clear whether using fs_sendrec is the best option, it is at least
an improvement.
Also remove some legacy cruft.
Each block driver now gets to specify whether it is a disk block
driver, which implies it wants the library to handle getting and
setting partitions for it.
The NetBSD libc provides a mechanism to have versions of system calls.
By 'renaming' symbols to a new version, freshly compiled programs will
automatically use the new symbol iff they use the proper header files. The
old, not renamed, version of the symbol will still exist (after being moved
to the compat directory), so old programs can still link.
Since MINIX doesn't support dynamic linking, the whole rename mechanism
doesn't really work for us. However, removing it would create a huge diff
with the current NetBSD libc.
A lot of the compat code relies on things we don't (seem to) have, and
therefore does not get built and linked. This causes trouble for tools like
autoconf, which will fail to find the renamed symbols. For example,
currently select gets renamed to __select50 in libc. Autoconf looks for
'select' and doesn't find it and reports we don't have it. This is where
the compat.S stub comes into play: it generates the old symbols and jumps to
the new symbols. However, as this is done in one object file, all renamed
symbols get linked together, causing binaries to be huge. This patch fixes
that by generating an object file for each renamed symbol.
This patch also makes the MISSING_SYSCALLS more complete and marginally
reduces the diff with NetBSD.
The implementation is in libblockdriver, and works transparently for
all block drivers. The new btrace(8) tool can be used to control block
tracing; see ``man btrace'' for details.
. always install them (overwrite)
. source minix one from /etc/defaults/rc.conf
so that it'll get read on existing installs
without overwriting rc.conf (doesn't happen by default
as it's user-editable), needed for new netconf system
. reported by Tenkawa
This patch separates the character and block driver communication
protocols. The old character protocol remains the same, but a new
block protocol is introduced. The libdriver library is replaced by
two new libraries: libchardriver and libblockdriver. Their exposed
API, and drivers that use them, have been updated accordingly.
Together, libbdev and libblockdriver now completely abstract away
the message format used by the block protocol. As the memory driver
is both a character and a block device driver, it now implements its
own message loop.
The most important semantic change made to the block protocol is that
it is no longer possible to return both partial results and an error
for a single transfer. This simplifies the interaction between the
caller and the driver, as the I/O vector no longer needs to be copied
back. Also, drivers are now no longer supposed to decide based on the
layout of the I/O vector when a transfer should be cut short. Put
simply, transfers are now supposed to either succeed completely, or
result in an error.
After this patch, the state of the various pieces is as follows:
- block protocol: stable
- libbdev API: stable for synchronous communication
- libblockdriver API: needs slight revision (the drvlib/partition API
in particular; the threading API will also change shortly)
- character protocol: needs cleanup
- libchardriver API: needs cleanup accordingly
- driver restarts: largely unsupported until endpoint changes are
reintroduced
As a side effect, this patch eliminates several bugs, hacks, and gcc
-Wall and -W warnings all over the place. It probably introduces a
few new ones, too.
Update warning: this patch changes the protocol between MFS and disk
drivers, so in order to use old/new images, the MFS from the ramdisk
must be used to mount all file systems.
