freebsd kernel with SKQ
Go to file
Kenneth D. Merry 8900f4b872 Fix a race condition in CAM peripheral free handling, locking
in the CAM XPT bus traversal code, and a number of other periph level
issues.

cam_periph.h,
cam_periph.c:	Modify cam_periph_acquire() to test the CAM_PERIPH_INVALID
		flag prior to allowing a reference count to be gained
		on a peripheral.  Callers of this function will receive
		CAM_REQ_CMP_ERR status in the situation of attempting to
		reference an invalidated periph.  This guarantees that
		a peripheral scheduled for a deferred free will not
		be accessed during its wait for destruction.

		Panic during attempts to drop a reference count on
		a peripheral that already has a zero reference count.

		In cam_periph_list(), use a local sbuf with SBUF_FIXEDLEN
		set so that mallocs do not occur while the xpt topology
		lock is held, regardless of the allocation policy of the
		passed in sbuf.

		Add a new routine, cam_periph_release_locked_buses(),
		that can be called when the caller already holds
		the CAM topology lock.

		Add some extra debugging for duplicate peripheral
		allocations in cam_periph_alloc().

		Treat CAM_DEV_NOT_THERE much the same as a selection
		timeout (AC_LOST_DEVICE is emitted), but forgo retries.

cam_xpt.c:      Revamp the way the EDT traversal code does locking
		and reference counting.  This was broken, since it
		assumed that the EDT would not change during
		traversal, but that assumption is no longer valid.

		So, to prevent devices from going away while we
		traverse the EDT, make sure we properly lock
		everything and hold references on devices that
		we are using.

		The two peripheral driver traversal routines should
		be examined.  xptpdperiphtraverse() holds the
		topology lock for the entire time it runs.
		xptperiphtraverse() is now locked properly, but
		only holds the topology lock while it is traversing
		the list, and not while the traversal function is
		running.

		The bus locking code in xptbustraverse() should
		also be revisited at a later time, since it is
		complex and should probably be simplified.

scsi_da.c:	Pay attention to the return value from cam_periph_acquire().

		Return 0 always from daclose() even if the disk is now gone.

		Add some rudimentary error injection support.

scsi_sg.c:	Fix reference counting in the sg(4) driver.

		The sg driver was calling cam_periph_release() on close,
		but never called cam_periph_acquire() (which increments
		the reference count) on open.

		The periph code correctly complained that the sg(4)
		driver was trying to decrement the refcount when it
		was already 0.

Sponsored by:	Spectra Logic
MFC after:	2 weeks
2012-01-12 00:41:48 +00:00
bin Spelling fixes for bin/ 2012-01-07 16:10:23 +00:00
cddl Add missing file permission to open(O_CREAT) call. This doesn't really matter 2012-01-04 07:25:10 +00:00
contrib Silence a warning about redefinition of TARGET_ELF on powerpc. 2012-01-06 18:37:49 +00:00
crypto Fix a problem whereby a corrupt DNS record can cause named to crash. [11:06] 2011-12-23 15:00:37 +00:00
etc Bunch of fixes to pfsync(4) module load/unload: 2012-01-09 08:50:22 +00:00
games Replace index() and rindex() calls with strchr() and strrchr(). 2012-01-03 18:51:58 +00:00
gnu Don't include <sys/timeb.h>. 2012-01-08 12:38:41 +00:00
include Import ACPICA 20120111. 2012-01-11 21:25:42 +00:00
kerberos5 Don't support OpenLDAP during lib32 build. 2011-12-06 12:03:01 +00:00
lib Fix prototype formatting (indentation, long lines, and continued lines). 2012-01-11 22:45:15 +00:00
libexec Fix warning when compiling with gcc46: 2012-01-10 02:55:35 +00:00
release Add hpt27xx to the hardware notes, 2012-01-11 18:38:52 +00:00
rescue -lreadline is not required anymore. 2011-11-29 03:27:09 +00:00
sbin - Fix a bug where pidfile was removed in SIGHUP when it hasn't changed in 2012-01-10 22:41:09 +00:00
secure Force linker error when created shared library contains a relocation 2011-12-06 11:28:17 +00:00
share Add the CAM Target Layer (CTL). 2012-01-12 00:34:33 +00:00
sys Fix a race condition in CAM peripheral free handling, locking 2012-01-12 00:41:48 +00:00
tools Import ACPICA 20120111. 2012-01-11 21:25:42 +00:00
usr.bin Add the CAM Target Layer (CTL). 2012-01-12 00:34:33 +00:00
usr.sbin Add the CAM Target Layer (CTL). 2012-01-12 00:34:33 +00:00
COPYRIGHT Happy 2012 to FreeBSD users in Samoa. 2011-12-31 04:38:04 +00:00
LOCKS
MAINTAINERS Farewall, sysinstall! You served us well for many years, but 10.0 is one 2011-10-03 15:13:09 +00:00
Makefile Replace 'chflags' with 'file flags' in a comment, since 'chflags' 2011-11-20 20:05:47 +00:00
Makefile.inc1 Fix the broken non-cross compile build. Oops! 2012-01-06 00:34:27 +00:00
Makefile.mips Retire TARGET_ABI. 2011-01-07 20:26:33 +00:00
ObsoleteFiles.inc Remove if_carp.ko. /boot/kernel should be upgraded atomically. 2011-12-19 12:50:12 +00:00
README Add the cddl/ directory. 2010-11-14 11:32:56 +00:00
UPDATING enable stop_scheduler_on_panic by default 2012-01-09 12:06:09 +00:00

This is the top level of the FreeBSD source directory.  This file
was last revised on:
$FreeBSD$

For copyright information, please see the file COPYRIGHT in this
directory (additional copyright information also exists for some
sources in this tree - please see the specific source directories for
more information).

The Makefile in this directory supports a number of targets for
building components (or all) of the FreeBSD source tree, the most
commonly used one being ``world'', which rebuilds and installs
everything in the FreeBSD system from the source tree except the
kernel, the kernel-modules and the contents of /etc.  The ``world''
target should only be used in cases where the source tree has not
changed from the currently running version.  See:
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html
for more information, including setting make(1) variables.

The ``buildkernel'' and ``installkernel'' targets build and install
the kernel and the modules (see below).  Please see the top of
the Makefile in this directory for more information on the
standard build targets and compile-time flags.

Building a kernel is a somewhat more involved process, documentation
for which can be found at:
   http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html
And in the config(8) man page.
Note: If you want to build and install the kernel with the
``buildkernel'' and ``installkernel'' targets, you might need to build
world before.  More information is available in the handbook.

The sample kernel configuration files reside in the sys/<arch>/conf
sub-directory (assuming that you've installed the kernel sources), the
file named GENERIC being the one used to build your initial installation
kernel.  The file NOTES contains entries and documentation for all possible
devices, not just those commonly used.  It is the successor of the ancient
LINT file, but in contrast to LINT, it is not buildable as a kernel but a
pure reference and documentation file.


Source Roadmap:
---------------
bin		System/user commands.

cddl		Various commands and libraries under the Common Development
		and Distribution License.

contrib		Packages contributed by 3rd parties.

crypto		Cryptography stuff (see crypto/README).

etc		Template files for /etc.

games		Amusements.

gnu		Various commands and libraries under the GNU Public License.
		Please see gnu/COPYING* for more information.

include		System include files.

kerberos5	Kerberos5 (Heimdal) package.

lib		System libraries.

libexec		System daemons.

release		Release building Makefile & associated tools.

rescue		Build system for statically linked /rescue utilities.

sbin		System commands.

secure		Cryptographic libraries and commands.

share		Shared resources.

sys		Kernel sources.

tools		Utilities for regression testing and miscellaneous tasks.

usr.bin		User commands.

usr.sbin	System administration commands.


For information on synchronizing your source tree with one or more of
the FreeBSD Project's development branches, please see:

  http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html