Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

bsd's ifconf conflicts with osv's; rename it.

We use the bsd version in <osv/ioctl.h>, since we currently don't support
the Linux-ABI variants of these ioctls.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Tested-By: Benoit Canet <benoit@irqsave.net>

The bsd ifaddr struct conflicts with the osv ifaddr struct, which is a
public interface.  Rename the bsd struct to avoid conflict.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Tested-By: Benoit Canet <benoit@irqsave.net>

Workaround a bytorder function conflict, and reconcile a declaration.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Tested-By: Benoit Canet <benoit@irqsave.net>

Some structures are duplicated; move the duplicates to a common header
<netinet/__in.h>.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Tested-By: Benoit Canet <benoit@irqsave.net>

Some structures are duplicated; deduplicate them.

A few are source-compatible but not binary-compatible; use the ones from
<bits/socket.h>.

Others are both source- and binary- compatible; put them in a new header
<sys/__socket.h> which is included from both.

Work around a problem with the byteorder functions/macros.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Tested-By: Benoit Canet <benoit@irqsave.net>

Update ->va_nlink() in zfs_getattr() in preparation for sys_link().

Signed-off-by: Raphael S. Carvalho <raphael.scarv@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Wire up the VOP_LINK vnode operation for ZFS in preparation for
sys_link().

Signed-off-by: Raphael S. Carvalho <raphael.scarv@gmail.com>
[ penberg: drop FIGNORE, cleanup, split ]
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

All the other fields of the pcpu structure BSD expects are initialized by
the event channel. Except for the cpu id, which the code expects to be already
initialized.

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>

Right now we send route messages with MTUs zeroed out. This can lead
to the following assert in ip_output.c (~line 308) triggering:

    KASSERT(mtu > 0, ("%s: mtu %d <= 0, rte=%p (rt_flags=0x%08x) ifp=%p",
        __func__, mtu, rte, (rte != NULL) ? rte->rt_flags : 0, ifp));

This happens because the code will assume that if there is a valid route, that
route will have a valid MTU. And in this case, will always use the route MTU
instead of the interface one.

When we allocate the route it has a valid MTU. But when we send the route
message, we will overwrite it with the value we see in the route message.  This
is done in rtsock.c:rt_setmetrics.

With this patch, those assertion stops happening.

A note: this wasn't been seen in local instalations, only on EC2. Looking at
it, there is nothing Xen specific. The reason it was not happening on local, is
that local traffic does not go through the default route, but rather through
the local 192.168.100.0/24 route. That one seems to take a different
configuration path, and thus sets the MTU correctly.

Added our copyright statements to some of the files in the top bsd/
directory, and in bsd/porting.

I only added our copyright to files which were completely by us - I did
not attempt to hunt which bsd or solaris files we modified to add our
copyright to them, I don't think this is important (or, we can do this
later).

I also found one header file (uma_stub.h) that had large chunks copied from
freebsd, so I added both the freebsd copyright and ours.

* %lu => %u when reading flush. The barrier flag had the same bug, but I
ended up recreating it for flush.
* Move check of xb_flags to after we check sc->flags != NULL, as spotted by
Dima

Not all Xen versions implement the barrier feature in their pv disks. Such is
the case in Amazon EC2. For those, we should interpret the flush request and
wait for the requests until they are all handled. Also, we can still try to use
one of either barriers or flush-disk operations before we resort to guest-side
software implementation. Our driver currently only tests for one of them, so
this patch also implements flush requests.

Luckily, the implementation of xb_dump (which we don't currently use) needs to
do that as well, and this is also quite well isolated in xb_quiesce(). All we need
to do is call xb_quiesce() if flushing is not available in our backend

Even Lords make brown paper bag mistakes. This is a left over code from my
initial testing, where the buffer where set with pre existing values to make
sure they were going through.  I forgot to remove them. As a result reads were
fine, but writes would just wipe the previous data from the buffer.
Incidentally, the "write-then-read-the-data-back" test I was doing would also
obviously pass, so I haven't noticed this so far.

Fix is to just leave the buffer alone.

msleep() measure times in units of 1/hz seconds. We had hz = 1,000,000,
which gives excellent resolution (microsecond) but a terible range
(limits msleep()'s timeout to 35 minutes).

We had a program (Cassandra) doing poll() with a timeout of 2 hours,
which caused msleep to think we gave a negative timeout.

This patch reduces hz to 1,000, i.e., have msleep() operate in the same units
as poll(). Looking at the code, I don't believe this change will have any
ill-effects - we don't need higher resolution (freebsd code is used to
hz=1,000, which is the default there), and the code converts time units to
hz's correctly, always using the hz macro. The allowed range for timeouts will
grow to over 24 days - and match poll()'s allowed range.

This patch implements GSI interrupt support for Xen bus.
Needed in Xen environments w/o vector callbacks for HVM.
One example of such an environment is Amazon EC2.

We cannot read the partition table from the device if the device is not marked
as ready, since all IO will stall. I believe it should be fine to just mark the
device ready before we mark our state as connected. With that change, it all
proceed normally.

Xen has hard requirements on page transfers, and how to feed the grant tables.
The address need to be page aligned, since the pfns and not addresses are used,
and we need to provide at least a full page per buffer, since the hypervisor is
free to fill any data within the page.

To achieve that, the netfront driver will use m_cljget to attach an extended
buffer to the mbuf, from the jumbop zone, since they are page-sized. However,
two problems arise from this:

1) Allocating a page goes through malloc_large. Our implementation of malloc_large
is currently terribly inefficient, and that creates a very heavy contention site.

What I am doing with this patch is to switch our uma implementation to
alloc_page / free_page instead of malloc if the caller of zcreate so specified
(and then of course, specify it for the jumbop cache)

2) The refcount that is attached in the end of the buffer would either extend the
buffer to 4100 bytes - defeating our purpose, or then the buffer would have to be
PAGE_SIZE - 4, to accomodate for the refcount. But since the hypervisor will write
to the whole page, it will eventually overwrite the refcount.

To address that, I am allocating an external reference counter. BSD already
have some infrastructure to do that, and I am taking advantage of this.
However, I have found no way of implementing this in a way in which the
reference count can be easily deduceable from the address of the extended
buffer, without having the supporting mbuf to start from. Any external data
structure such as hashes would probably make freeing way too slow. Thankfully,
uma_find_refcnt and the UMA_ZONE_REFCNT seems to be used mostly in the
setup/destruction phase (the mbuf refcount is used directly, open coded). So my
proposal here is to remove the UMA_ZONE_REFCNT for that zone.

If a crashed OSv guest is restarted, ZFS mount causes a GPF in early
startup:

  VFS: mounting zfs at /usr
  zfs: mounting osv/usr from device /dev/vblk1
  Aborted

GDB backtrace points finger at zfs_rmnode():

  #0  processor::halt_no_interrupts () at ../../arch/x64/processor.hh:212
  #1  0x00000000003e7f2a in osv::halt () at ../../core/power.cc:20
  #2  0x000000000021cdd4 in abort (msg=0x636df0 "Aborted\n") at ../../runtime.cc:95
  #3  0x000000000021cda2 in abort () at ../../runtime.cc:86
  #4  0x000000000044c149 in osv::generate_signal (siginfo=..., ef=0xffffc0003ffe7008) at ../../libc/signal.cc:44
  #5  0x000000000044c220 in osv::handle_segmentation_fault (addr=72, ef=0xffffc0003ffe7008) at ../../libc/signal.cc:55
  #6  0x0000000000366df3 in page_fault (ef=0xffffc0003ffe7008) at ../../core/mmu.cc:876
  #7  <signal handler called>
  #8  0x0000000000345eaa in zfs_rmnode (zp=0xffffc0003d1de400)
      at ../../bsd/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_dir.c:611
  #9  0x000000000035650c in zfs_zinactive (zp=0xffffc0003d1de400)
      at ../../bsd/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_znode.c:1355
  #10 0x0000000000345be1 in zfs_unlinked_drain (zfsvfs=0xffffc0003ddfe000)
      at ../../bsd/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_dir.c:523
  #11 0x000000000034f45c in zfsvfs_setup (zfsvfs=0xffffc0003ddfe000, mounting=true)
      at ../../bsd/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c:881
  #12 0x000000000034f7a4 in zfs_domount (vfsp=0xffffc0003de02000, osname=0x6b14cb "osv/usr")
      at ../../bsd/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c:1016
  #13 0x000000000034f98c in zfs_mount (mp=0xffffc0003de02000, dev=0x6b14d7 "/dev/vblk1", flags=0, data=0x6b14cb)
      at ../../bsd/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c:1415
  #14 0x0000000000406852 in sys_mount (dev=0x6b14d7 "/dev/vblk1", dir=0x6b14a3 "/usr", fsname=0x6b14d3 "zfs", flags=0, data=0x6b14cb)
      at ../../fs/vfs/vfs_mount.c:171
  #15 0x00000000003eff97 in mount_usr () at ../../fs/vfs/main.cc:1415
  #16 0x0000000000203a89 in do_main_thread (_args=0xffffc0003fe9ced0) at ../../loader.cc:215
  #17 0x0000000000448575 in pthread_private::pthread::pthread(void* (*)(void*), void*, sigset_t, pthread_private::thread_attr const*)::{lambda()#1}::operator()() const () at ../../libc/pthread.cc:59
  #18 0x00000000004499d3 in std::_Function_handler<void(), pthread_private::pthread::pthread(void* (*)(void*), void*, sigset_t, const pthread_private::thread_attr*)::__lambda0>::_M_invoke(const std::_Any_data &) (__functor=...)
      at ../../external/gcc.bin/usr/include/c++/4.8.1/functional:2071
  #19 0x000000000037e602 in std::function<void ()>::operator()() const (this=0xffffc0003e170038)
      at ../../external/gcc.bin/usr/include/c++/4.8.1/functional:2468
  #20 0x00000000003bae3e in sched::thread::main (this=0xffffc0003e170010) at ../../core/sched.cc:581
  #21 0x00000000003b8c92 in sched::thread_main_c (t=0xffffc0003e170010) at ../../arch/x64/arch-switch.hh:133
  #22 0x0000000000399c8e in thread_main () at ../../arch/x64/entry.S:101

The problem is that ZFS tries to check if the znode is an attribute
directory and trips over zp->z_vnode being NULL.  However, as explained
in commit b7ee91ef ("zfs: port vop_lookup"), we don't even support
extended attributes so drop the check completely for OSv.

SIOCAIFADDR appends an address to the interface's address list instead of
replacing it.  This causes 'ifconfig' to display 0.0.0.0 (the first address
configured) instead of the correct address obtained by dhcp.

Fix by also deleting the existing address, if it exists.

We'll need this for any pathname related actions.

Create a new dentry structure for pathname components, following the Linux
VFS model.  The vnodes are left-as is for now but are always fronted by
dentries for pathname lookups.  In a second step they will be moved to
use non-pathname indices.

[penberg: fix open(O_CREAT|O_EXCL) breakage ]

While planning to run tests on Xen today, I found my guests in current tip
failing to mount ZFS. I spent some time debugging the memory allocator, since
it was the culprit last time: only to find out we were not even reaching the
memory allocator.

I noticed then that ZFS was failing with error 75 -> EOVERFLOW. Looking
further, one of our bootup messages was showing the disks as "0MB".

That information is read from the xenstore, and it was being read correctly.
However, by the time we calculate the disk size, this is no longer correct,
indicating a stack corruption.

I found out the culprit to be a subsequent call to xs_gather, which calls a
variant of scanf internally. The call was being passed a %lu argument to read
an int variable, which would explain the corruption if the # of sectors was
right before it in the stack.

Indeed, with this fix, ZFS fails in a different way now =)

Wastes memory, esp. with power-of-two allocations.

The xen block driver needs some extra state not needed for the network drivers.
Namely, the same way virtio-blk does, we need to tell the block layer which is
our strategy, read and write functions. For that, we need some extra code that
I am implementing in xenfront-blk.cc.

BSD expects its sector number to be already provided by the bio. We could add this field
to the bio, but it is easier just to calculate it from the given offset.

There are many places in which the bios are filled up, including many in the zfs code. So
it is easier to change them just here.

Simple implementation of BSD's bus_dma interface. Since we are constrained by virtual
environments, we are able to cut out most of the things.

We will use it in our bus_dma implementation

Our version of biodone takes two arguments instead of one. Adjust it, passing
the status in the second argument as expected. We could adjust our biodone()
function to be the same as BSD's, but I decided to do the other way around, at
least for now: we need locking and synchronization via cond vars at bio
completion, and although the xenfront driver has its own lock for this, the
other users rely on the internal lock for correctness. Adjusting them would
mean adjusting their locking semantics, which although doable, is just more
work than adjusting xenfront.

We need to add our headers first, but the rest should be ready to go.

It provides very simple queue / dequeue functions for the bios.

BSD code does not initialize its structures.. It works well when memory is
previously zeroed but not otherwise. Xen hypervisor compiled in debug mode
fills memory with a poison pattern, and then the code breaks for those
variables. Force them to 0.

Those headers are needed from blkfront and netfront. Some of them are empty stubs
are usual but some are import from BSD. I am bringing them separately so it is
obvious what they are here for.

The macro to calculate ring size are really gigantic and nested. Somewhere,
somehow, gcc believes that one of the size calculations yields a variadic size.
It doesn't seem to be the case to me, but maybe we are using (or lacking) some
compiler flag that can explain this.

Although this is clearly suboptimal, let us set with this for now. It should not
be a huge problem unless we update xen headers.

Because softc is private - only a void pointer outside blkfront, we need
a helper here to return the correct device from its softc representation.
This will be used by the osv side to determine where to trigger IO to