(this commit is just the first stage). Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
vm_mtx does not recurse and is required for most low level
vm operations.
faults can not be taken without holding Giant.
Memory subsystems can now call the base page allocators safely.
Almost all atomic ops were removed as they are covered under the
vm mutex.
Alpha and ia64 now need to catch up to i386's trap handlers.
FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).
Reviewed (partially) by: jake, jhb
mtx_enter(lock, type) becomes:
mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)
similarily, for releasing a lock, we now have:
mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.
The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.
Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:
MTX_QUIET and MTX_NOSWITCH
The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:
mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.
Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.
Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.
Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.
Finally, caught up to the interface changes in all sys code.
Contributors: jake, jhb, jasone (in no particular order)
of explicit calls to lockmgr. Also provides macros for the flags
pased to specify shared, exclusive or release which map to the
lockmgr flags. This is so that the use of lockmgr can be easily
replaced with optimized reader-writer locks.
- Add some locking that I missed the first time.
syscall compare against a variable sv_minsigstksz in struct
sysentvec as to properly take the size of the machine- and
ABI dependent struct sigframe into account.
The SVR4 and iBCS2 modules continue to have a minsigstksz of
8192 to preserve behavior. The real values (if different) are
not known at this time. Other ABI modules use the real
values.
The native MINSIGSTKSZ is now defined as follows:
Arch MINSIGSTKSZ
---- -----------
alpha 4096
i386 2048
ia64 12288
Reviewed by: mjacob
Suggested by: bde
Add lockdestroy() and appropriate invocations, which corresponds to
lockinit() and must be called to clean up after a lockmgr lock is no
longer needed.
a loop down in pmap_init_pt(). A subtraction causes the number of
pages to become negative, that was assigned to an unsigned variable,
and there is a lot of iteration. The bug is due to the ELF image
activator not properly checking for its files being the correct size
as specified by the ELF header.
The solution is to check that the header doesn't ask for part of a
file when that part of the file doesn't exist. Make sure to set
VEXEC at the proper times to make the executables immutable (remove
race conditions). Also, the ELF format specifiies header entries
that allow embedding of other executables (hence how ld-elf.so.1
gets loaded, but not the same as loading shared libraries), so those
executables need to be set VEXEC, too, so they're immutable.
Reviewed by: peter
maintainers.
After we established our branding method of writing upto 8 characters of
the OS name into the ELF header in the padding; the Binutils maintainers
and/or SCO (as USL) decided that instead the ELF header should grow two new
fields -- EI_OSABI and EI_ABIVERSION. Each of these are an 8-bit unsigned
integer. SCO has assigned official values for the EI_OSABI field. In
addition to this, the Binutils maintainers and NetBSD decided that a better
ELF branding method was to include ABI information in a ".note" ELF
section.
With this set of changes, we will now create ELF binaries branded using
both "official" methods. Due to the complexity of adding a section to a
binary, binaries branded with ``brandelf'' will only brand using the
EI_OSABI method. Also due to the complexity of pulling a section out of an
ELF file vs. poking around in the ELF header, our image activator only
looks at the EI_OSABI header field.
Note that a new kernel can still properly load old binaries except for
Linux static binaries branded in our old method.
*
* For a short period of time, ``ld'' will also brand ELF binaries
* using our old method. This is so people can still use kernel.old
* with a new world. This support will be removed before 5.0-RELEASE,
* and may not last anywhere upto the actual release. My expiration
* time for this is about 6mo.
*
This
This feature allows you to specify if mmap'd data is included in
an application's corefile.
Change the type of eflags in struct vm_map_entry from u_char to
vm_eflags_t (an unsigned int).
Reviewed by: dillon,jdp,alfred
Approved by: jkh
to `register_t *'. This fixes bugs like misplacement of argc and argv
on the user stack on i386's with 64-bit longs. We still use longs to
represent "words" like argc and argv, and assume that they are on the
stack (and that there is stack). The suword() and fuword() families
should also use register_t.
Alot of the code in sys/kern directly accesses the *Q_HEAD and *Q_ENTRY
structures for list operations. This patch makes all list operations
in sys/kern use the queue(3) macros, rather than directly accessing the
*Q_{HEAD,ENTRY} structures.
This batch of changes compile to the same object files.
Reviewed by: phk
Submitted by: Jake Burkholder <jake@checker.org>
PR: 14914
Merge the contents (less some trivial bordering the silly comments)
of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>. This puts
the #defines for the vm_inherit_t and vm_prot_t types next to their
typedefs.
This paves the road for the commit to follow shortly: change
useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE}
as argument.
I don't know if it was intentional or not, but it would have printed out:
/compat/linux/foo/bar.so: interpreter not found
If it was, then I've broken it. De-constifying the 'interp' variable
or carrying the constness through to elf_load_file() are alternatives.
dynamicly linked binaries to run in a chroot'd environment with "emul_path"
as the new root. The new behavior of loading interpreters is identical to the
principle of overlaying.
PR: 10145
It never makes sense to specify MAP_COPY_NEEDED without also specifying
MAP_COPY_ON_WRITE, and vice versa. Thus, MAP_COPY_ON_WRITE suffices.
Reviewed by: David Greenman <dg@root.com>
in "src/sys/sys/param.h".
Fix the ELF image activator so that it can handle dynamic linkers
which are executables linked at a fixed address. This improves
compliance with the ABI spec, and it opens the door to possibly
better dynamic linker performance in the future. I've experimented
a bit with a fixed-address dynamic linker, and it works fine. But
I don't have any measurements yet to determine whether it's
worthwhile.
Also, remove a few calculations that were never used for anything.
I will increment __FreeBSD_version, since this adds a new capability
to the kernel that the dynamic linker might some day rely upon.
is the preparation step for moving pmap storage out of vmspace proper.
Reviewed by: Alan Cox <alc@cs.rice.edu>
Matthew Dillion <dillon@apollo.backplane.com>
to an architecture-specific value defined in <machine/elf.h>. This
solves problems on large-memory systems that have a high value for
MAXDSIZ.
The load address is controlled by a new macro ELF_RTLD_ADDR(vmspace).
On the i386 it is hard-wired to 0x08000000, which is the standard
SVR4 location for the dynamic linker.
On the Alpha, the dynamic linker is loaded MAXDSIZ bytes beyond
the start of the program's data segment. This is the same place
a userland mmap(0, ...) call would put it, so it ends up just below
all the shared libraries. The rationale behind the calculation is
that it allows room for the data segment to grow to its maximum
possible size.
These changes have been tested on the i386 for several months
without problems. They have been tested on the Alpha as well,
though not for nearly as long. I would like to merge the changes
into 3.1 within a week if no problems have surfaced as a result of
them.
attempt to optimize forks but were essentially given-up on due to
problems and replaced with an explicit dup of the vm_map_entry structure.
Prior to the removal, they were entirely unused.
