Commit Graph

52 Commits

Author SHA1 Message Date
Michael S. Tsirkin
b7a413015d virtio: disable multiport console support.
Move MULTIPORT feature and related config changes
out of exported headers, and disable the feature
at runtime.

At this point, it seems less risky to keep code around
until we can enable it than rip it out completely.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-04-08 09:46:19 +09:30
Rusty Russell
9ff4cfab82 virtio: console makes incorrect assumption about virtio API
The get_buf() API sets the second arg to the number of bytes *written*
by the other side; in this case it should be zero as these are output buffers.

lguest gets this right (obviously kvm's console doesn't), resulting in
continual buildup of console writes.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Amit Shah <amit.shah@redhat.com>
2010-04-08 09:46:17 +09:30
François Diakhaté
162a689a13 virtio: console: Fix early_put_chars usage
Currently early_put_chars is not used by virtio_console because it can
only be used once a port has been found, at which point it's too late
because it is no longer needed. This patch should fix it.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-04-08 09:46:15 +09:30
Tejun Heo
5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Amit Shah
2de16a493c virtio: console: Check if port is valid in resize_console
The console port could have been hot-unplugged. Check if it is valid
before working on it.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-03-22 14:24:55 +02:00
Amit Shah
ec64213c4d virtio: console: Generate a kobject CHANGE event on adding 'name' attribute
When the host lets us know what 'name' a port is assigned, we create the
sysfs 'name' attribute. Generate a 'change' event after this so that
udev wakes up and acts on the rules for virtio-ports (currently there's
only one rule that creates a symlink from the 'name' to the actual char
device).

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-03-22 14:24:53 +02:00
Amit Shah
335a64a5c2 virtio: console: Use better variable names for fill_queue operation
We want to keep track of the number of buffers added to a vq. Use
nr_added_bufs instead of 'ret'.

Also, the users of fill_queue() overloaded a local 'err' variable to
check the numbers of buffers allocated. Use nr_added_bufs instead of
err.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reported-by: Juan Quintela <quintela@redhat.com>
2010-03-04 13:40:39 +05:30
Amit Shah
604b2ad7cc virtio: console: Fix type of 'len' as unsigned int
We declare 'len' as int type but it should be 'unsigned int', as
get_buf() wants it to be.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reported-by: Juan Quintela <quintela@redhat.com>
2010-03-04 13:40:33 +05:30
Amit Shah
d693356192 virtio: console: Fill ports' entire in_vq with buffers
Instead of allocating just one buffer for a port's in_vq, fill
the entire in_vq with buffers so the host need not stall while
an application consumes the data and makes the buffer available
again for the host.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:23:06 +10:30
Amit Shah
22a29eacd2 virtio: console: Error out if we can't allocate buffers for control queue
With MULTIPORT support, the control queue is an integral part of the
functioning of the device. If we can't get any buffers allocated, the
host won't be able to relay important information and the device may not
function as intended.

Ensure 'probe' doesn't succeed until the control queue has at least one
buffer allocated for its ivq.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:23:04 +10:30
Amit Shah
7177876fea virtio: console: Add ability to remove module
Add the ability to remove the virtio_console module.

This aids debugging.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:23:04 +10:30
Amit Shah
a9cdd48557 virtio: console: Ensure no memleaks in case of unused buffers
If unused data exists in in_vq, ensure we flush that first and then
detach unused buffers, which will ensure all buffers from the in_vq are
removed.

Also ensure we free the buffers after detaching them.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:23:03 +10:30
Amit Shah
298add723a virtio: console: show error message if hvc_alloc fails for console ports
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:23:02 +10:30
Amit Shah
d99393effd virtio: console: Add debugfs files for each port to expose debug info
This is helpful in examining ports' state.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:23:01 +10:30
Amit Shah
1f7aa42d16 virtio: console: Add ability to hot-unplug ports
Remove port data; deregister from the hvc core if it's a console port.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:23:00 +10:30
Amit Shah
7f5d810dac virtio: console: Handle port hot-plug
If the 'nr_ports' variable in the config space is updated to a higher
value, that means new ports have been hotplugged.

Introduce a new workqueue to handle such updates and create new ports.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:58 +10:30
Amit Shah
88f251ac58 virtio: console: Remove cached data on port close
Remove any data that we might have in a port's inbuf when closing a port
or when any data is received when a port is closed.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:57 +10:30
Amit Shah
431edb8a8b virtio: console: Register with sysfs and create a 'name' attribute for ports
The host can set a name for ports so that they're easily discoverable
instead of going by the /dev/vportNpn naming. This attribute will be
placed in /sys/class/virtio-ports/vportNpn/name. udev scripts can then
create symlinks to the port using the name.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:56 +10:30
Amit Shah
3c7969ccb5 virtio: console: Ensure only one process can have a port open at a time
Add a guest_connected field that ensures only one process
can have a port open at a time.

This also ensures we don't have a race when we later add support for
dropping buffers when closing the char dev and buffer caching is turned
off for the particular port.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:55 +10:30
Amit Shah
2030fa496d virtio: console: Add file operations to ports for open/read/write/poll
Allow guest userspace applications to open, read from, write to, poll
the ports via the char dev interface.

When a port gets opened, a notification is sent to the host via a
control message indicating a connection has been established. Similarly,
on closing of the port, a notification is sent indicating disconnection.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:54 +10:30
Amit Shah
fb08bd274d virtio: console: Associate each port with a char device
The char device will be used as an interface by applications on the
guest to communicate with apps on the host.

The devices created are placed in /dev/vportNpn where N is the
virtio-console device number and n is the port number for that device.

One dynamic major device number is allocated for each device and minor
numbers are allocated for the ports contained within that device.

The file operation for the char devs will be added in the following
commits.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:53 +10:30
Amit Shah
b766ceed5b virtio: console: Prepare for writing to userspace buffers
When ports get advertised as char devices, the buffers will come from
userspace. Equip the fill_readbuf function with the ability to write
to userspace buffers.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:53 +10:30
Amit Shah
17634ba255 virtio: console: Add a new MULTIPORT feature, support for generic ports
This commit adds a new feature, MULTIPORT. If the host supports this
feature as well, the config space has the number of ports defined for
that device. New ports are spawned according to this information.

The config space also has the maximum number of ports that can be
spawned for a particular device. This is useful in initializing the
appropriate number of virtqueues in advance, as ports might be
hot-plugged in later.

Using this feature, generic ports can be created which are not tied to
hvc consoles.

We also open up a private channel between the host and the guest via
which some "control" messages are exchanged for the ports, like whether
the port being spawned is a console port, resizing the console window,
etc.

Next commits will add support for hotplugging and presenting char
devices in /dev/ for bi-directional guest-host communication.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:52 +10:30
Amit Shah
f997f00bf8 virtio: console: Introduce a send_buf function for a common path for sending data to host
Adding support for generic ports that will write to userspace will need
some code changes.

Consolidate the write routine into send_buf() and put_chars() now just
calls into the new function.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:51 +10:30
Amit Shah
203baab8ba virtio: console: Introduce function to hand off data from host to readers
In preparation for serving data to userspace (generic ports) as well as
in-kernel users (hvc consoles), separate out the functionality common to
both in a 'fill_readbuf()' function.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:50 +10:30
Amit Shah
2658a79acf virtio: console: Separate out find_vqs operation into a different function
With support for multiple ports, each port will have its own input and
output vqs. Prepare the probe function for this change.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:49 +10:30
Amit Shah
cfa6d37925 virtio: console: Separate out console init into a new function
Console ports could be hot-added. Also, with the new multiport support,
a port is identified as a console port only if the host sends a control
message.

Move the console port init into a separate function so it can be invoked
from other places.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:48 +10:30
Amit Shah
4f23c573c0 virtio: console: Separate out console-specific data into a separate struct
Move out console-specific stuff into a separate struct from 'struct
port' as we need to maintain two lists: one for all the ports (which
includes consoles) and one only for consoles since the hvc callbacks
only give us the vtermno.

This makes console handling cleaner.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:47 +10:30
Amit Shah
cb06e3676b virtio: console: ensure console size is updated on hvc open
When multiple console support is added, ensure each port's size gets
updated when a new one is opened via hvc.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:45 +10:30
Amit Shah
1c85bf3544 virtio: console: struct ports for multiple ports per device.
Rather than assume a single port, add a 'struct ports_device' which
stores data related to all the ports for that device.

Currently, there's only one port and is hooked up with hvc, but that
will change.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:43 +10:30
Rusty Russell
d8a02bd58a virtio: console: remove global var
Now we can use an allocation function to remove our global console variable.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:42 +10:30
Amit Shah
38edf58d73 virtio: console: don't assume a single console port.
Keep a list of all ports being used as a console, and provide a lock
and a lookup function.  The hvc callbacks only give us a vterm number,
so we need to map this.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:41 +10:30
Rusty Russell
73954488b1 virtio: console: use vdev->priv to avoid accessing global var.
Part of removing our "one console" assumptions, use vdev->priv to point
to the port (currently == the global console).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:40 +10:30
Amit Shah
a3cde44908 virtio: console: introduce a get_inbuf helper to fetch bufs from in_vq
This makes taking locks around the get_buf vq operation easier, as well
as complements the add_inbuf() operation.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:38 +10:30
Amit Shah
e27b519807 virtio: console: ensure add_inbuf can work for multiple ports as well
add_inbuf() assumed one port and one inbuf per port. Remove that
assumption.

Also move the function so that put_chars and get_chars are together.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:37 +10:30
Amit Shah
fdb9a05455 virtio: console: encapsulate buffer information in a struct
Collect port buffer, used_len, offset fields into a single structure.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:36 +10:30
Rusty Russell
21206ede88 virtio: console: port encapsulation
We are heading towards a multiple-"port" system, so as part of weaning off
globals we encapsulate the information into 'struct port'.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:34 +10:30
Amit Shah
f550804ab9 virtio: console: We support only one device at a time
We support only one virtio_console device at a time. If multiple are
found, error out if one is already initialized.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:33 +10:30
Rusty Russell
1dff399616 hvc_console: make the ops pointer const.
This is nicer for modern R/O protection.  And noone needs it non-const, so
constify the callers as well.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
To: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: linuxppc-dev@ozlabs.org
2010-02-24 14:22:32 +10:30
Rusty Russell
971f339000 virtio: console: statically initialize virtio_cons
That way, we can make it const as is good kernel style.  We use a separate
indirection for the early console, rather than mugging ops.put_chars.

We rename it hv_ops, too.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:31 +10:30
Rusty Russell
a23ea92474 virtio: console: comment cleanup
Remove old lguest-style comments.

[Amit: - wingify comments acc. to kernel style
       - indent comments ]

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-02-24 14:22:30 +10:30
Christian Borntraeger
e95646c3ec virtio: let header files include virtio_ids.h
Rusty,

commit 3ca4f5ca73
    virtio: add virtio IDs file
moved all device IDs into a single file. While the change itself is
a very good one, it can break userspace applications. For example
if a userspace tool wanted to get the ID of virtio_net it used to
include virtio_net.h. This does no longer work, since virtio_net.h
does not include virtio_ids.h.
This patch moves all "#include <linux/virtio_ids.h>" from the C
files into the header files, making the header files compatible with
the old ones.

In addition, this patch exports virtio_ids.h to userspace.

CC: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-10-22 16:39:28 +10:30
Fernando Luis Vazquez Cao
3ca4f5ca73 virtio: add virtio IDs file
Virtio IDs are spread all over the tree which makes assigning new IDs
bothersome. Putting them together should make the process less error-prone.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-23 22:26:32 +09:30
Rusty Russell
3c1b27d504 virtio: make add_buf return capacity remaining
This API change means that virtio_net can tell how much capacity
remains for buffers.  It's necessarily fuzzy, since
VIRTIO_RING_F_INDIRECT_DESC means we can fit any number of descriptors
in one, *if* we can kmalloc.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Dinesh Subhraveti <dineshs@us.ibm.com>
2009-09-23 22:26:31 +09:30
Michael S. Tsirkin
d2a7ddda9f virtio: find_vqs/del_vqs virtio operations
This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
and updates all drivers. This is needed for MSI support, because MSI
needs to know the total number of vectors upfront.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (+ lguest/9p compile fixes)
2009-06-12 22:16:36 +09:30
Rusty Russell
9499f5e7ed virtio: add names to virtqueue struct, mapping from devices to queues.
Add a linked list of all virtqueues for a virtio device: this helps for
debugging and is also needed for upcoming interface change.

Also, add a "name" field for clearer debug messages.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:16:36 +09:30
Christian Borntraeger
c29834584e virtio_console: support console resizing
this patch uses the new hvc callback hvc_resize to set the window size
which allows to change the tty size of hvc_console via a hvc_resize
function.

I have added a new feature bit VIRTIO_CONSOLE_F_SIZE. The driver will
change the window size on tty open and via the config_changed callback
of the transport. Currently lguest and kvm_s390 have not implemented this
callback, but the callback can be implemented at a later point in time.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30 09:26:10 +10:30
Hendrik Brueckner
fc362e2e0e hvc_console: Add a hangup notifier for backends
I have added a hangup notifier that can be used by hvc console
backends to handle a tty hangup. The default irq hangup notifier
calls the notifier_del_irq() for compatibility.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-10-22 10:59:54 +11:00
Christian Borntraeger
91fcad19d0 virtio_console: use virtqueue notification for hvc_console
This patch exploits the new notifier callbacks of the hvc_console. We can
use the virtio callbacks instead of the polling code.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25 12:06:06 +10:00
Rusty Russell
a586d4f601 virtio: simplify config mechanism.
Previously we used a type/len pair within the config space, but this
seems overkill.  We now simply define a structure which represents the
layout in the config space: the config space can now only be extended
at the end.

The main driver-visible changes:
1) We indicate what fields are present with an explicit feature bit.
2) Virtqueues are explicitly numbered, and not in the config space.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-04 23:49:57 +11:00