The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:
- Improved driver model:
The old TTY layer has a driver model that is not abstract enough to
make it friendly to use. A good example is the output path, where the
device drivers directly access the output buffers. This means that an
in-kernel PPP implementation must always convert network buffers into
TTY buffers.
If a PPP implementation would be built on top of the new TTY layer
(still needs a hooks layer, though), it would allow the PPP
implementation to directly hand the data to the TTY driver.
- Improved hotplugging:
With the old TTY layer, it isn't entirely safe to destroy TTY's from
the system. This implementation has a two-step destructing design,
where the driver first abandons the TTY. After all threads have left
the TTY, the TTY layer calls a routine in the driver, which can be
used to free resources (unit numbers, etc).
The pts(4) driver also implements this feature, which means
posix_openpt() will now return PTY's that are created on the fly.
- Improved performance:
One of the major improvements is the per-TTY mutex, which is expected
to improve scalability when compared to the old Giant locking.
Another change is the unbuffered copying to userspace, which is both
used on TTY device nodes and PTY masters.
Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.
Obtained from: //depot/projects/mpsafetty/...
Approved by: philip (ex-mentor)
Discussed: on the lists, at BSDCan, at the DevSummit
Sponsored by: Snow B.V., the Netherlands
dcons(4) fixed by: kan
When I ported most applications away from <sgtty.h>, I noticed none of
them were actually using these definitions. I kept them in place,
because I didn't want to touch tools like pstat(8) and stty(1).
In preparation for the MPSAFE TTY layer, remove these definitions. This
doesn't have any impact with respect to binary compatibility (see
tty_conf.c).
We couldn now add an #error to <sys/ioctl_compat.h> when included
outside the kernel. Unfortunately, kdump's mkioctls includes this file
unconditionally.
Approved by: philip (mentor)
incorrect and should have been poining to &tty, tp is a virtual
address from the coredump, while we should obtain the address through
the tty struct.
Approved by: imp (mentor, implicit trivial changes)
MFC after: 1 week
Submitted by: Ed Schouten (ed at 80836 dot nl)
setenv(3) by tracking the size of the memory allocated instead of using
strlen() on the current value.
Convert all calls to POSIX from historic BSD API:
- unsetenv returns an int.
- putenv takes a char * instead of const char *.
- putenv no longer makes a copy of the input string.
- errno is set appropriately for POSIX. Exceptions involve bad environ
variable and internal initialization code. These both set errno to
EFAULT.
Several patches to base utilities to handle the POSIX changes from
Andrey Chernov's previous commit. A few I re-wrote to use setenv()
instead of putenv().
New regression module for tools/regression/environ to test these
functions. It also can be used to test the performance.
Bump __FreeBSD_version to 700050 due to API change.
PR: kern/99826
Approved by: wes
Approved by: re (kensmith)
Not because I admit they are technically wrong and not because of bug
reports (I receive nothing). But because I surprisingly meets so
strong opposition and resistance so lost any desire to continue that.
Anyone who interested in POSIX can dig out what changes and how
through cvs diffs.
when printing swapinfo output, rather than (total), as that is (strictly
speaking) more accurate.
Pointed out by: Rob <spamrefuse at yahoo dot com>
MFC after: 3 days
format, with humanize_number(3).
- Move the common parts of the code that prints the sizes for a single
swap device and the total to a single function to avoid repeating
the humanize_number() stuff all over the place.
- Change the type of CONVERT() from intmax_t to int64_t, since this
makes calling humanize_number() easier but cast the values to
intmax_t before printing them, to make use of the %jd format that
printf() supports.
- Document the new -h flag in the manpage and bump its date.
Approved by: pjd
Useful tips: brooks
MFC after: 2 weeks
that this provokes. "Wherever possible" means "In the kernel OR NOT
C++" (implying C).
There are places where (void *) pointers are not valid, such as for
function pointers, but in the special case of (void *)0, agreement
settles on it being OK.
Most of the fixes were NULL where an integer zero was needed; many
of the fixes were NULL where ascii <nul> ('\0') was needed, and a
few were just "other".
Tested on: i386 sparc64
a constant string of little information these days.
This removes the need to #include <vm/swap_pager.h> which is due to
become a kernel only include file.
. Print the column headers centered (except for the left-aligned
TYPE header) using a different header for architectures where
sizeof(uintptr_t) is not four.
. Consistently do not print a '0x' prefix for hexadecimal values.
. Separate columns by a single space character.
. Pad the columns presenting an address or offset enough to hold
their respective largest value.
. Do not restrict the output to unknown file types, inodes and
sockets; allow displaying of pipes, fifos, kqueues and crypto file
descriptors too.
- Shorten an overly long line by removing a cast of printf's return
value to void.
PR: alpha/45240
Tested on: i386, sparc64, alpha
pointer types, and remove a huge number of casts from code using it.
Change struct xfile xf_data to xun_data (ABI is still compatible).
If we need to add a #define for f_data and xf_data we can, but I don't
think it will be necessary. There are no operational changes in this
commit.
use and has been broken in -CURRENT for a long time.
Clean up unneeded entries in the nlist array.
Implement kvm-backed ttymode (which we never had before). Incomplete as we
do not (yet?) print the correct device, sid or pgid.
Sponsored by: DARPA, NAI Labs
