This areas is called the comm pages. It is used to provide fast access to
several data and functions.
The comm pages are mapped starting at 0xffff800 (address chosed so that
absolute branch can be used, so it can be accessed even when dynamic linking
is not ready). NetBSD has the user stack here, so we need to provide a
Darwin-specific stack setup routine which sets the top of the stack at
0xbfff0000.
This implementation is not complete but it does enough to get MacOS X.3
starting again (static binaries run, dynamic binaries still have an issue).
in the comm pages functions, we only implement bcopy, pthread_self and
memcpy.
TODO:
- clean up the powerpc specific code from MD parts
- for now we map only one page to avoid a crash, we want two pages.
- write all the comm functions.
want more flexible namecache handling.
it just looks up a dnlc entry and vget() the result vnode.
ie. no automatic entry removal, no automatic vnode locking.
discussed on tech-kern@.
doesn't advance while we're waiting on the lock. In fact, try to take
the lock even before blocking interrupts: the lock is locking "lasttime"
against other callers of cc_microtime(), not against the clock routines,
and if we take a clock interrupt while waiting for the lock, that's one
we don't have to take after the computations, but before returning to
the caller, and that makes the data a little fresher to the caller.
Moreover, inverting the order of splXXX() and simple_lock() permits us
to unblock interrupts before doing the long division.
With this, finally, performance of "ntpd" on my MP i386 seems to be no
worse than on non-MP i386, so this may fix PR kern/24207.
for consistency with M_FREE() and m_freem(). Affected files:
sys/mbuf.h
kern/uipc_socket2.c
kern/uipc_mbuf.c
net/if_ethersubr.c
netatalk/ddp_input.c
nfs/nfs_socket.c
a ktraced file descriptor that has already been invalidated. Change
all ktrace functions to propagate the error from ktrwrite() and
check for it. Thanks to Pavel Cahyna for finding this and giving
a perfect bug report.
[should be pulled up for 2.0]
doing copy-on-write.
- Change VFS_SNAPSHOT() to return the snapshot vnode locked.
- Make the IO path for copy-on-write and snapshot-read more lightweight.
Avoids deadlocks where vn_rdwr(...READ...) has a shared lock and needs
to copy-on-write.
Avoids deadlocks/panics where to clean pages the copy-on-write needs
to allocate pages for its VOP_PUTPAGES().
L_COWINPROGRESS part approved by: Jason R. Thorpe <thorpej@netbsd.org>
overloading "usec". The counter isn't counting micro-seconds, and using
the same variable to mean two different things is false economy: with
this change, the compiled object is 72 bytes smaller on i386, and the
code is easier to understand, to boot.
We do an MGETHDR)() for each mbuf "packet" of the input chain, to hold
the socket address prepended to that "packet". If those MGETHDR()s
ever failed, we would leak all the successfully-allocated mbuf
headers. Leak noted by Yamamoto-san (yamt@NetBSD.org); thanks for catching it!
Add socketbuf invariant-checking macros to sbappendaddrchain(), and
replace a stray bcopy() with memcpy(), also as suggested by Yamamoto-san.
Fix a potential race condition when reallocating storage for file descriptors
(even for non-SMP kernels).
Add missing locks for `struct file' ref count updates.
Introduce new socket-layer function sbappendaddrchain() to
sys/kern/uipc_socket2.c: like sbappendaddr(), only takes a chain of
records and appends the entire chain in one pass. sbappendaddrchain()
also takes an `sbprio' argument, which indicates the caller requires
special `reliable' handling of the socket-buffer. `sbprio' is
described in sys/sys/socketvar.h, although (for now) the different
levels are not yet implemented.
Rework sys/netipsec/key.c PF_KEY DUMP responses to build a chain of
mbuf records, one record per dump response. Unicast the entire chain
to the requestor, with all-or-none semantics.
Changed files;
sys/socketvar.h kern/uipc_socket2.c netipsec/key.c
Reviewed by:
Jason Thorpe, Thor Lancelot Simon, post to tech-kern.
Todo: request pullup to 2.0 branch. Post-2.0, rework sysctl() API for
dumps to use new record-chain constructors. Actually implement
the distinct service levels in sbappendaddrchain() so we can use them
to make PF_KEY ACQUIRE messages more reliable.
- Not enabled by default. Needs kernel option FFS_SNAPSHOT.
- Change parameters of ffs_blkfree.
- Let the copy-on-write functions return an error so spec_strategy
may fail if the copy-on-write fails.
- Change genfs_*lock*() to use vp->v_vnlock instead of &vp->v_lock.
- Add flag B_METAONLY to VOP_BALLOC to return indirect block buffer.
- Add a function ffs_checkfreefile needed for snapshot creation.
- Add special handling of snapshot files:
Snapshots may not be opened for writing and the attributes are read-only.
Use the mtime as the time this snapshot was taken.
Deny mtime updates for snapshot files.
- Add function transferlockers to transfer any waiting processes from
one lock to another.
- Add vfsop VFS_SNAPSHOT to take a snapshot and make it accessible through
a vnode.
- Add snapshot support to ls, fsck_ffs and dump.
Welcome to 2.0F.
Approved by: Jason R. Thorpe <thorpej@netbsd.org>
