Commit Graph

263 Commits

Author SHA1 Message Date
Rusty Russell 856c608827 lguest: rename switcher_page to switcher_pages.
There is a single page with the Switcher in it, but it's followed by 2
pages per Host CPU.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-22 15:31:35 +09:30
Rusty Russell c215a8b9eb lguest: remove RESERVE_MEM constant.
We can use switcher_addr directly.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-22 15:31:35 +09:30
Rusty Russell 68a644d734 lguest: check vaddr not pgd for Switcher protection.
We currently assume that the Switcher the top pgd; we want to remove
this assumption, so check that vaddr is OK, rather then checking pgd
index.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-22 15:31:34 +09:30
Rusty Russell 406a590ba1 lguest: prepare to make SWITCHER_ADDR a variable.
We currently use the whole top PGD entry for the switcher, but that's
hitting the fixmap in some configurations (mainly, large NR_CPUS).
Introduce a variable, currently set to the constant.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-04-22 15:31:33 +09:30
Wanlong Gao 289d1054e9 lguest: fix paths in comments
After commit 07fe997, lguest tool has already moved from
Documentation/virtual/lguest/ to tools/lguest/.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-07 09:56:46 +11:00
Linus Torvalds 3c834b6f41 All trivial, thanks to the stuff which didn't quite make it time.
Cheers,
 Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio updates from Rusty Russell:
 "All trivial, thanks to the stuff which didn't quite make it time"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_console: Initialize guest_connected=true for rproc_serial
  virtio: use module_virtio_driver.
  virtio: Add module driver macro for virtio drivers.
  virtio_console: Use virtio device index to generate port name
  virtio: make pci_device_id const
  virtio: make config_ops const
  virtio-mmio: fix wrong comment about register offset
  virtio_console: Let unconnected rproc device receive data.
2013-02-26 14:49:12 -08:00
Linus Torvalds 21eaab6d19 tty/serial patches for 3.9-rc1
Here's the big tty/serial driver patches for 3.9-rc1.
 
 More tty port rework and fixes from Jiri here, as well as lots of
 individual serial driver updates and fixes.
 
 All of these have been in the linux-next tree for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial patches from Greg Kroah-Hartman:
 "Here's the big tty/serial driver patches for 3.9-rc1.

  More tty port rework and fixes from Jiri here, as well as lots of
  individual serial driver updates and fixes.

  All of these have been in the linux-next tree for a while."

* tag 'tty-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
  tty: mxser: improve error handling in mxser_probe() and mxser_module_init()
  serial: imx: fix uninitialized variable warning
  serial: tegra: assume CONFIG_OF
  TTY: do not update atime/mtime on read/write
  lguest: select CONFIG_TTY to build properly.
  ARM defconfigs: add missing inclusions of linux/platform_device.h
  fb/exynos: include platform_device.h
  ARM: sa1100/assabet: include platform_device.h directly
  serial: imx: Fix recursive locking bug
  pps: Fix build breakage from decoupling pps from tty
  tty: Remove ancient hardpps()
  pps: Additional cleanups in uart_handle_dcd_change
  pps: Move timestamp read into PPS code proper
  pps: Don't crash the machine when exiting will do
  pps: Fix a use-after free bug when unregistering a source.
  pps: Use pps_lookup_dev to reduce ldisc coupling
  pps: Add pps_lookup_dev() function
  tty: serial: uartlite: Support uartlite on big and little endian systems
  tty: serial: uartlite: Fix sparse and checkpatch warnings
  serial/arc-uart: Miscll DT related updates (Grant's review comments)
  ...

Fix up trivial conflicts, mostly just due to the TTY config option
clashing with the EXPERIMENTAL removal.
2013-02-21 13:41:04 -08:00
Stephen Hemminger 9350393239 virtio: make config_ops const
It is just a table of function pointers, make it const for cleanliness and security
reasons.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-02-11 15:32:17 +10:30
Joe Millenbach 4f73bc4dd3 tty: Added a CONFIG_TTY option to allow removal of TTY
The option allows you to remove TTY and compile without errors. This
saves space on systems that won't support TTY interfaces anyway.
bloat-o-meter output is below.

The bulk of this patch consists of Kconfig changes adding "depends on
TTY" to various serial devices and similar drivers that require the TTY
layer.  Ideally, these dependencies would occur on a common intermediate
symbol such as SERIO, but most drivers "select SERIO" rather than
"depends on SERIO", and "select" does not respect dependencies.

bloat-o-meter output comparing our previous minimal to new minimal by
removing TTY.  The list is filtered to not show removed entries with awk
'$3 != "-"' as the list was very long.

add/remove: 0/226 grow/shrink: 2/14 up/down: 6/-35356 (-35350)
function                                     old     new   delta
chr_dev_init                                 166     170      +4
allow_signal                                  80      82      +2
static.__warned                              143     142      -1
disallow_signal                               63      62      -1
__set_special_pids                            95      94      -1
unregister_console                           126     121      -5
start_kernel                                 546     541      -5
register_console                             593     588      -5
copy_from_user                                45      40      -5
sys_setsid                                   128     120      -8
sys_vhangup                                   32      19     -13
do_exit                                     1543    1526     -17
bitmap_zero                                   60      40     -20
arch_local_irq_save                          137     117     -20
release_task                                 674     652     -22
static.spin_unlock_irqrestore                308     260     -48

Signed-off-by: Joe Millenbach <jmillenbach@gmail.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-18 16:15:27 -08:00
Kees Cook 3594ec0a70 drivers/lguest: remove depends on CONFIG_EXPERIMENTAL
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2013-01-11 11:38:05 -08:00
Alex Russell 681f206611 lguest: fix typo
Signed-off-by: Alex Russell <giles.alex@hotmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:19:06 +10:30
Linus Torvalds dc92b1f9ab Merge branch 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull virtio changes from Rusty Russell:
 "New workflow: same git trees pulled by linux-next get sent straight to
  Linus.  Git is awkward at shuffling patches compared with quilt or mq,
  but that doesn't happen often once things get into my -next branch."

* 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (24 commits)
  lguest: fix occasional crash in example launcher.
  virtio-blk: Disable callback in virtblk_done()
  virtio_mmio: Don't attempt to create empty virtqueues
  virtio_mmio: fix off by one error allocating queue
  drivers/virtio/virtio_pci.c: fix error return code
  virtio: don't crash when device is buggy
  virtio: remove CONFIG_VIRTIO_RING
  virtio: add help to CONFIG_VIRTIO option.
  virtio: support reserved vqs
  virtio: introduce an API to set affinity for a virtqueue
  virtio-ring: move queue_index to vring_virtqueue
  virtio_balloon: not EXPERIMENTAL any more.
  virtio-balloon: dependency fix
  virtio-blk: fix NULL checking in virtblk_alloc_req()
  virtio-blk: Add REQ_FLUSH and REQ_FUA support to bio path
  virtio-blk: Add bio-based IO path for virtio-blk
  virtio: console: fix error handling in init() function
  tools: Fix pthread flag for Makefile of trace-agent used by virtio-trace
  tools: Add guest trace agent as a user tool
  virtio/console: Allocate scatterlist according to the current pipe size
  ...
2012-10-07 21:04:56 +09:00
Michael S. Tsirkin 6457f126c8 virtio: support reserved vqs
virtio network device multiqueue support reserves
vq 3 for future use (useful both for future extensions and to make it
pretty - this way receive vqs have even and transmit - odd numbers).
Make it possible to skip initialization for
specific vq numbers by specifying NULL for name.
Document this usage as well as (existing) NULL callback.

Drivers using this not coded up yet, so I simply tested
with virtio-pci and verified that this patch does
not break existing drivers.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:15 +09:30
Jason Wang 17bb6d4088 virtio-ring: move queue_index to vring_virtqueue
Instead of storing the queue index in transport-specific virtio structs,
this patch moves them to vring_virtqueue and introduces an helper to get
the value.  This lets drivers simplify their management and tracing of
virtqueues.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:15 +09:30
Suresh Siddha 9c6ff8bbb6 lguest, x86: handle guest TS bit for lazy/non-lazy fpu host models
Instead of using unlazy_fpu() check if user_has_fpu() and set/clear
the host TS bits so that the lguest works fine with both the
lazy/non-lazy FPU host models with minimal changes.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1345842782-24175-6-git-send-email-suresh.b.siddha@intel.com
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-09-18 15:52:09 -07:00
Stratos Psomadakis b6c96c0214 lguest: Make sure interrupt is allocated ok by lguest_setup_irq
Make sure the interrupt is allocated correctly by lguest_setup_irq (check the
return value of irq_alloc_desc_at for -ENOMEM)

Signed-off-by: Stratos Psomadakis <psomas@cslab.ece.ntua.gr>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cleanups and commentry)
2012-01-12 15:44:47 +10:30
Davidlohr Bueso 07fe9977b6 lguest: move the lguest tool to the tools directory
This is a better location instead of having it in Documentation.

Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (fixed compile)
2012-01-12 15:44:47 +10:30
Jacek Galowicz 39082f7e59 lguest: switch segment-voodoo-numbers to readable symbols
When studying lguest's x86 segment descriptor code, it is not longer
necessary to have the Intel x86 architecture manual open on the page
with the segment descriptor illustration to understand the crazy
numbers assigned to both descriptor structure halves a/b.
Now the struct desc_struct's fields, like suggested by
Glauber de Oliveira Costa in 2008, are used.

Signed-off-by: Jacek Galowicz <jacek@galowicz.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12 15:44:47 +10:30
Rusty Russell 7b21e34fd1 virtio: harsher barriers for rpmsg.
We were cheating with our barriers; using the smp ones rather than the
real device ones.  That was fine, until rpmsg came along, which is
used to talk to a real device (a non-SMP CPU).

Unfortunately, just putting back the real barriers (reverting
d57ed95d) causes a performance regression on virtio-pci.  In
particular, Amos reports netbench's TCP_RR over virtio_net CPU
utilization increased up to 35% while throughput went down by up to
14%.

By comparison, this branch is in the noise.

Reference: https://lkml.org/lkml/2011/12/11/22

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12 15:44:42 +10:30
Linus Torvalds 9753dfe19a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1958 commits)
  net: pack skb_shared_info more efficiently
  net_sched: red: split red_parms into parms and vars
  net_sched: sfq: extend limits
  cnic: Improve error recovery on bnx2x devices
  cnic: Re-init dev->stats_addr after chip reset
  net_sched: Bug in netem reordering
  bna: fix sparse warnings/errors
  bna: make ethtool_ops and strings const
  xgmac: cleanups
  net: make ethtool_ops const
  vmxnet3" make ethtool ops const
  xen-netback: make ops structs const
  virtio_net: Pass gfp flags when allocating rx buffers.
  ixgbe: FCoE: Add support for ndo_get_fcoe_hbainfo() call
  netdev: FCoE: Add new ndo_get_fcoe_hbainfo() call
  igb: reset PHY after recovering from PHY power down
  igb: add basic runtime PM support
  igb: Add support for byte queue limits.
  e1000: cleanup CE4100 MDIO registers access
  e1000: unmap ce4100_gbe_mdio_base_virt in e1000_remove
  ...
2012-01-06 17:22:09 -08:00
Seiichi Ikarashi 1cf8343f55 x86: Fix rflags in FAKE_STACK_FRAME
The x86_64 kernel pushes the fake kernel stack in
arch/x86/kernel/entry_64.S:FAKE_STACK_FRAME, and
rflags register in it does not conform to the specification.

Although Intel's manual[1] says bit 1 of it shall be set to 1,
this bit is cleared to 0 on pushing the fake stack.

[1] Intel(R) 64 and IA-32 Architectures Software Developer's Manual
    Vol.1 3-21 Figure 3-8. EFLAGS Register

If it is not on purpose, it is better to be fixed, because
it can lead some tools misunderstanding the stack frame. For example,
"crash" utility[2] actually detects it and warns you like
below:

       RIP: ffffffff8005dfa2  RSP: ffff8104ce0c7f58  RFLAGS: 00000200
       [...]

       bt: WARNING: possibly bogus exception frame

Signed-off-by: Seiichi Ikarashi <s.ikarashi@jp.fujitsu.com>
Tested-by: Masayoshi MIZUMA <m.mizuma@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06 10:02:38 +01:00
Rick Jones 66846048f5 enable virtio_net to return bus_info in ethtool -i consistent with emulated NICs
Add a new .bus_name to virtio_config_ops then modify virtio_net to
call through to it in an ethtool .get_drvinfo routine to report
bus_info in ethtool -i output which is consistent with other
emulated NICs and the output of lspci.

Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-16 17:26:46 -05:00
Paul Gortmaker 39a0e33da0 lguest: add export.h to lguest files for THIS_MODULE/EXPORT_SYMBOL
We need this in advance of the module.h cleanup, or we'll
get compile errors like this:

  CC      drivers/lguest/lguest_device.o
drivers/lguest/lguest_device.c: In function ‘lguest_devices_init’:
drivers/lguest/lguest_device.c:490: error: ‘THIS_MODULE’ undeclared (first use in this function)

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:32:13 -04:00
Michal Hocko 0acf00014b lguest: move process freezing before pending signals check
run_guest tries to freeze the current process after it has handled
pending interrupts and before it calls lguest_arch_run_guest.
This doesn't work nicely if the task has been killed while being frozen
and when we want to handle that signal as soon as possible.
Let's move try_to_freeze before we check for pending signal so that we
can get out of the loop as soon as possible.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-10-27 10:56:18 +10:30
Rusty Russell b56e3215d4 lguest: Allow running under paravirt-enabled KVM.
We actually can run under KVM, as it doesn't paravirtualize anything we
need to use; reduce the check to checking we are the normal ringlevel.

Reported-by: Stefanos Geraggelos <sgerag@cslab.ece.ntua.gr>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au># HG changeset patch
2011-10-27 10:56:17 +10:30
Rusty Russell 996ba96a97 lguest: Fix in/out emulation
We were blatting too much of the register.  Linux didn't care, but in
theory it might.

Reported-by: Jonas Maebe <jonas.maebe@elis.ugent.be>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-07-22 14:39:51 +09:30
Rusty Russell 9f54288def lguest: update comments
Also removes a long-unused #define and an extraneous semicolon.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-07-22 14:39:50 +09:30
Rusty Russell 3c3ed482dc lguest: Simplify device initialization.
We used to notify the Host every time we updated a device's status.  However,
it only really needs to know when we're resetting the device, or failed to
initialize it, or when we've finished our feature negotiation.

In particular, we used to wait for VIRTIO_CONFIG_S_DRIVER_OK in the
status byte before starting the device service threads.  But this
corresponds to the successful finish of device initialization, which
might (like virtio_blk's partition scanning) use the device.  So we
had a hack, if they used the device before we expected we started the
threads anyway.

Now we hook into the finalize_features hook in the Guest: at that
point we tell the Launcher that it can rely on the features we have
acked.  On the Launcher side, we look at the status at that point, and
start servicing the device.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-07-22 14:39:49 +09:30
Rusty Russell 6d7a5d1ea3 lguest: don't rewrite vmcall instructions
Now we no longer use vmcall, we don't need to rewrite it in the Guest.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-07-22 14:39:49 +09:30
Rusty Russell 5dea1c88ed lguest: use a special 1:1 linear pagetable mode until first switch.
The Host used to create some page tables for the Guest to use at the
top of Guest memory; it would then tell the Guest where this was.  In
particular, it created linear mappings for 0 and 0xC0000000 addresses
because lguest used to switch to its real page tables quite late in
boot.

However, since d50d8fe19 Linux initialized boot page tables in
head_32.S even before the "are we lguest?" boot jump.  So, now we can
simplify things: the Host pagetable code assumes 1:1 linear mapping
until it first calls the LHCALL_NEW_PGTABLE hypercall, which we now do
before we reach C code.

This also means that the Host doesn't need to know anything about the
Guest's PAGE_OFFSET.  (Non-Linux guests might not even have such a
thing).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-07-22 14:39:48 +09:30
Rob Landley 6151658751 Correct occurrences of
- Documentation/kvm/ to Documentation/virtual/kvm
- Documentation/uml/ to Documentation/virtual/uml
- Documentation/lguest/ to Documentation/virtual/lguest
throughout the kernel source tree.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
2011-05-06 09:27:55 -07:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Rusty Russell ced05dd741 lguest: compile fixes
arch/x86/lguest/boot.c: In function ‘lguest_init_IRQ’:
arch/x86/lguest/boot.c:824: error: macro "__this_cpu_write" requires 2 arguments, but only 1 given
arch/x86/lguest/boot.c:824: error: ‘__this_cpu_write’ undeclared (first use in this function)
arch/x86/lguest/boot.c:824: error: (Each undeclared identifier is reported only once
arch/x86/lguest/boot.c:824: error: for each function it appears in.)

drivers/lguest/x86/core.c: In function ‘copy_in_guest_info’:
drivers/lguest/x86/core.c:94: error: lvalue required as left operand of assignment

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-01-20 21:37:29 +10:30
Christoph Lameter c9f2954964 lguest: Use this_cpu_ops
Use this_cpu_ops in a couple of places in lguest.

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-01-20 21:37:29 +10:30
Arnd Bergmann 6038f373a3 llseek: automatically add .llseek fop
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time.  Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
//   but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
   *off = E
|
   *off += E
|
   func(..., off, ...)
|
   E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
  *off = E
|
  *off += E
|
  func(..., off, ...)
|
  E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
 ...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
 .llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
 .read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
 .write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
 .open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
...  .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
...  .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
...  .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+	.llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
 .write = write_f,
 .read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
2010-10-15 15:53:27 +02:00
Rusty Russell 091ebf07a2 lguest: stop using KVM hypercall mechanism
This is a partial revert of 4cd8b5e2a1 "lguest: use KVM hypercalls";
we revert to using (just as questionable but more reliable) int $15 for
hypercalls.  I didn't revert the register mapping, so we still use the
same calling convention as kvm.

KVM in more recent incarnations stopped injecting a fault when a guest
tried to use the VMCALL instruction from ring 1, so lguest under kvm
fails to make hypercalls.  It was nice to share code with our KVM
cousins, but this was overreach.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matias Zabaljauregui <zabaljauregui@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
2010-04-14 21:43:56 +09:30
Rusty Russell 5094aeafbb lguest: workaround cmpxchg8b_emu by ignoring cli in the guest.
It's only used by cmpxchg8b_emu (see db677ffa5f for the gory
details), and fixing that to be paravirt aware would be more work than
simply ignoring it (and AFAICT only help lguest).  This makes lguest
work on machines which have cmpxchg8b, for kernels compiled for older
processors.

(We can't emulate it properly: the popf which expects to restore interrupts
does not trap).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: virtualization@lists.osdl.org
2010-04-14 21:43:54 +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
Rusty Russell 3e27249c84 lguest: fix bug in setting guest GDT entry
We kill the guest, but then we blatt random stuff.

Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-04 12:33:33 -08:00
Linus Torvalds d0316554d3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
  m68k: rename global variable vmalloc_end to m68k_vmalloc_end
  percpu: add missing per_cpu_ptr_to_phys() definition for UP
  percpu: Fix kdump failure if booted with percpu_alloc=page
  percpu: make misc percpu symbols unique
  percpu: make percpu symbols in ia64 unique
  percpu: make percpu symbols in powerpc unique
  percpu: make percpu symbols in x86 unique
  percpu: make percpu symbols in xen unique
  percpu: make percpu symbols in cpufreq unique
  percpu: make percpu symbols in oprofile unique
  percpu: make percpu symbols in tracer unique
  percpu: make percpu symbols under kernel/ and mm/ unique
  percpu: remove some sparse warnings
  percpu: make alloc_percpu() handle array types
  vmalloc: fix use of non-existent percpu variable in put_cpu_var()
  this_cpu: Use this_cpu_xx in trace_functions_graph.c
  this_cpu: Use this_cpu_xx for ftrace
  this_cpu: Use this_cpu_xx in nmi handling
  this_cpu: Use this_cpu operations in RCU
  this_cpu: Use this_cpu ops for VM statistics
  ...

Fix up trivial (famous last words) global per-cpu naming conflicts in
	arch/x86/kvm/svm.c
	mm/slab.c
2009-12-14 09:58:24 -08:00
Tejun Heo 390dfd95c5 percpu: make misc percpu symbols unique
This patch updates misc percpu related symbols such that percpu
symbols are unique and don't clash with local symbols.  This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.

* drivers/crypto/padlock-aes.c: s/last_cword/paes_last_cword/

* drivers/lguest/x86/core.c: s/last_cpu/lg_last_cpu/

* drivers/s390/net/netiucv.c: rename the variable used in a macro to
  avoid clashing with percpu symbol

* arch/mn10300/kernel/kprobes.c: replace current_ prefix with cur_ for
  static variables.  Please note that percpu symbol current_kprobe
  can't be changed as it's used by generic code.

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
2009-10-29 22:34:14 +09:00
Alexey Dobriyan d43c36dc6b headers: remove sched.h from interrupt.h
After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-10-11 11:20:58 -07:00
Alexey Dobriyan 828c09509b const: constify remaining file_operations
[akpm@linux-foundation.org: fix KVM]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:11 -07:00
Linus Torvalds 1f0918d03f Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  lguest: don't force VIRTIO_F_NOTIFY_ON_EMPTY
  lguest: cleanup for map_switcher()
  lguest: use PGDIR_SHIFT for PAE code to allow different PAGE_OFFSET
  lguest: use set_pte/set_pmd uniformly for real page table entries
  lguest: move panic notifier registration to its expected place.
  virtio_blk: add support for cache flush
  virtio: add virtio IDs file
  virtio: get rid of redundant VIRTIO_ID_9P definition
  virtio: make add_buf return capacity remaining
  virtio_pci: minor MSI-X cleanups
2009-09-23 09:23:45 -07:00
Xiao Guangrong 6c189d8312 lguest: cleanup for map_switcher()
We can use alloc_page() instead of get_zeroed_page() and virt_to_page()

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-23 22:26:47 +09:30
Rusty Russell fb100d78c0 lguest: use PGDIR_SHIFT for PAE code to allow different PAGE_OFFSET
We still assume the Guest and Host have the same PAGE_OFFSET settings,
but now we don't assume 0xC0000000.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matias Zabaljauregui <zabaljauregui@gmail.com>
2009-09-23 22:26:46 +09:30
Rusty Russell 4c1ea3dd71 lguest: use set_pte/set_pmd uniformly for real page table entries
If we're building a pte, we can use simple assigment; only use set_pte
etc. when we're actually going to use that destination as a PTE.  I
don't know that we'll ever run under Xen, but it's neater.

And use set_pte/set_pmd rather than assuming native_ versions, even
though that's probably true for most people.

(Includes compile fix by Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matias Zabaljauregui <zabaljauregui@gmail.com>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
2009-09-23 22:26:46 +09:30
Anand Gadiyar fd589a8f0a trivial: fix typo "to to" in multiple files
Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-21 15:14:55 +02:00
Rusty Russell 1842f23c05 lguest and virtio: cleanup struct definitions to Linux style.
I've been doing this for years, and akpm picked me up on it about 12
months ago.  lguest partly serves as example code, so let's do it Right.

Also, remove two unused fields in struct vblk_info in the example launcher.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
2009-07-30 16:03:46 +09:30
Rusty Russell a91d74a3c4 lguest: update commentry
Every so often, after code shuffles, I need to go through and unbitrot
the Lguest Journey (see drivers/lguest/README).  Since we now use RCU in
a simple form in one place I took the opportunity to expand that explanation.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
2009-07-30 16:03:46 +09:30
Rusty Russell 2e04ef7691 lguest: fix comment style
I don't really notice it (except to begrudge the extra vertical
space), but Ingo does.  And he pointed out that one excuse of lguest
is as a teaching tool, it should set a good example.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
2009-07-30 16:03:45 +09:30
Dan Carpenter f294526279 lguest: dereferencing freed mem in add_eventfd()
"new" was freed and then dereferenced.  Also the return value wasn't being
used so I modified the caller as well.

Compile tested only.  Found by smatch (http://repo.or.cz/w/smatch.git).

regards,
dan carpenter

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-07-30 16:03:43 +09:30
Davide Libenzi 27de22d03d lguest: remove unnecessary forward struct declaration
While fixing lg.h to drop the fwd declaration, I noticed
there's another one ;)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-07-17 21:47:44 +09:30
Davide Libenzi 133890103b eventfd: revised interface and cleanups
Change the eventfd interface to de-couple the eventfd memory context, from
the file pointer instance.

Without such change, there is no clean way to racely free handle the
POLLHUP event sent when the last instance of the file* goes away.  Also,
now the internal eventfd APIs are using the eventfd context instead of the
file*.

This patch is required by KVM's IRQfd code, which is still under
development.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Gregory Haskins <ghaskins@novell.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:55:58 -07:00
Linus Torvalds 7f3591cfac Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguest
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguest: (31 commits)
  lguest: add support for indirect ring entries
  lguest: suppress notifications in example Launcher
  lguest: try to batch interrupts on network receive
  lguest: avoid sending interrupts to Guest when no activity occurs.
  lguest: implement deferred interrupts in example Launcher
  lguest: remove obsolete LHREQ_BREAK call
  lguest: have example Launcher service all devices in separate threads
  lguest: use eventfds for device notification
  eventfd: export eventfd_signal and eventfd_fget for lguest
  lguest: allow any process to send interrupts
  lguest: PAE fixes
  lguest: PAE support
  lguest: Add support for kvm_hypercall4()
  lguest: replace hypercall name LHCALL_SET_PMD with LHCALL_SET_PGD
  lguest: use native_set_* macros, which properly handle 64-bit entries when PAE is activated
  lguest: map switcher with executable page table entries
  lguest: fix writev returning short on console output
  lguest: clean up length-used value in example launcher
  lguest: Segment selectors are 16-bit long. Fix lg_cpu.ss1 definition.
  lguest: beyond ARRAY_SIZE of cpu->arch.gdt
  ...
2009-06-12 09:32:26 -07:00
Rusty Russell 5dac051bc6 lguest: remove obsolete LHREQ_BREAK call
We no longer need an efficient mechanism to force the Guest back into
host userspace, as each device is serviced without bothering the main
Guest process (aka. the Launcher).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:11 +09:30
Rusty Russell df60aeef4f lguest: use eventfds for device notification
Currently, when a Guest wants to perform I/O it calls LHCALL_NOTIFY with
an address: the main Launcher process returns with this address, and figures
out what device to run.

A far nicer model is to let processes bind an eventfd to an address: if we
find one, we simply signal the eventfd.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Davide Libenzi <davidel@xmailserver.org>
2009-06-12 22:27:10 +09:30
Rusty Russell 9f155a9b3d lguest: allow any process to send interrupts
We currently only allow the Launcher process to send interrupts, but it
as we already send interrupts from the hrtimer, it's a simple matter of
extracting that code into a common set_interrupt routine.

As we switch to a thread per virtqueue, this avoids a bottleneck through the
main Launcher process.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:09 +09:30
Rusty Russell 92b4d8df84 lguest: PAE fixes
1) j wasn't initialized in setup_pagetables, so they weren't set up for me
   causing immediate guest crashes.

2) gpte_addr should not re-read the pmd from the Guest.  Especially
   not BUG_ON() based on the value.  If we ever supported SMP guests,
   they could trigger that.  And the Launcher could also trigger it
   (tho currently root-only).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:08 +09:30
Matias Zabaljauregui acdd0b6292 lguest: PAE support
This version requires that host and guest have the same PAE status.
NX cap is not offered to the guest, yet.

Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:08 +09:30
Matias Zabaljauregui ebe0ba84f5 lguest: replace hypercall name LHCALL_SET_PMD with LHCALL_SET_PGD
replace LHCALL_SET_PMD with LHCALL_SET_PGD hypercall name
(That's really what it is, and the confusion gets worse with PAE support)

Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reported-by: Jeremy Fitzhardinge <jeremy@goop.org>
2009-06-12 22:27:07 +09:30
Matias Zabaljauregui 90603d15fa lguest: use native_set_* macros, which properly handle 64-bit entries when PAE is activated
Some cleanups and replace direct assignment with native_set_* macros which properly handle 64-bit entries when PAE is activated

Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:06 +09:30
Matias Zabaljauregui ed1dc77810 lguest: map switcher with executable page table entries
Map switcher with executable page table entries.
(This bug didn't matter before PAE and hence NX support -- RR)

Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:06 +09:30
Matias Zabaljauregui f086122bb6 lguest: Segment selectors are 16-bit long. Fix lg_cpu.ss1 definition.
If GDT_ENTRIES were every > 256, this could become a problem.

Signed-off-by: Matias Zabaljauregui <zabaljauregui at gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:04 +09:30
Roel Kluin 81b79b01d0 lguest: beyond ARRAY_SIZE of cpu->arch.gdt
Do not go beyond ARRAY_SIZE of cpu->arch.gdt

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:04 +09:30
Rusty Russell a32a8813d0 lguest: improve interrupt handling, speed up stream networking
lguest never checked for pending interrupts when enabling interrupts, and
things still worked.  However, it makes a significant difference to TCP
performance, so it's time we fixed it by introducing a pending_irq flag
and checking it on irq_restore and irq_enable.

These two routines are now too big to patch into the 8/10 bytes
patch space, so we drop that code.

Note: The high latency on interrupt delivery had a very curious
effect: once everything else was optimized, networking without GSO was
faster than networking with GSO, since more interrupts were sent and
hence a greater chance of one getting through to the Guest!

Note2: (Almost) Closing the same loophole for iret doesn't have any
measurable effect, so I'm leaving that patch for the moment.

Before:
	1GB tcpblast Guest->Host:		30.7 seconds
	1GB tcpblast Guest->Host (no GSO):	76.0 seconds

After:
	1GB tcpblast Guest->Host:		6.8 seconds
	1GB tcpblast Guest->Host (no GSO):	27.8 seconds

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:03 +09:30
Rusty Russell abd41f037e lguest: fix race in halt code
When the Guest does the LHCALL_HALT hypercall, we go to sleep, expecting
that a timer or the Waker will wake_up_process() us.

But we do it in a stupid way, leaving a classic missing wakeup race.

So split maybe_do_interrupt() into interrupt_pending() and
try_deliver_interrupt(), and check maybe_do_interrupt() and the
"break_out" flag before calling schedule.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:02 +09:30
Rusty Russell a6c372de6e lguest: fix lguest wake on guest clock tick, or fd activity
The Launcher could be inside the Guest on another CPU; wake_up_process
will do nothing because it is "running".  kick_process will knock it
back into our kernel in this case, otherwise we'll miss it until the
next guest exit.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:01 +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
Rusty Russell 564346224d lguest: fix on Intel when KVM loaded (unhandled trap 13)
When KVM is loaded, and hence VT set up, the vmcall instruction in an
lguest guest causes a #GP, not #UD.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-26 12:13:11 -07:00
Rusty Russell a489f0b555 lguest: fix guest crash on non-linear addresses in gdt pvops
Fixes guest crash 'lguest: bad read address 0x4800000 len 256'

The new per-cpu allocator ends up handing a non-linear address to
write_gdt_entry.  We do __pa() on it, and hand it to the host, which
kills us.

I've long wanted to make the hypercall "LOAD_GDT_ENTRY" to match the IDT
code, but had no pressing reason until now.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: lguest@ozlabs.org
2009-04-19 23:14:01 +09:30
Matias Zabaljauregui 88df781afb lguest: fix crash on vmlinux images
Typical message: 'lguest: unhandled trap 6 at 0x418726 (0x0)'

vmlinux guests were broken by 4cd8b5e2a1
'lguest: use KVM hypercalls', which rewrites guest text from kvm hypercalls
to trap 31.

The Launcher mmaps the kernel image.  The Guest executes and
immediately faults in the first text page (read-only).  Then it hits a
hypercall, and we rewrite that hypercall, causing a copy-on-write.
But the Guest pagetables still refer to the old page: we fault again,
but as Host we see the hypercall already rewritten, and pass the fault
back to the Guest.  The Guest hasn't set up an IDT yet, so we kill it.

This doesn't happen with bzImages: they unpack themselves and so the
text pages are already read-write.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Patrick McHardy <kaber@trash.net>
2009-04-19 23:14:00 +09:30
Matias Zabaljauregui df1693abc4 lguest: use bool instead of int
Impact: clean up

Rusty told me, some time ago, that he had become a fan of "bool".
So, here are some replacements.

Signed-off-by: Matias Zabaljauregui <zabaljauregui at gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-30 21:55:25 +10:30
Matias Zabaljauregui 4cd8b5e2a1 lguest: use KVM hypercalls
Impact: cleanup

This patch allow us to use KVM hypercalls

Signed-off-by: Matias Zabaljauregui <zabaljauregui at gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-30 21:55:24 +10:30
Rusty Russell 6afbdd059c lguest: fix spurious BUG_ON() on invalid guest stack.
Impact: fix crash on misbehaving guest

gpte_addr() contains a BUG_ON(), insisting that the present flag is
set.  We need to return before we call it if that isn't the case.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
2009-03-30 21:55:23 +10:30
Ingo Molnar 6e15cf0486 Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2
Conflicts:
	arch/parisc/kernel/irq.c
	arch/x86/include/asm/fixmap_64.h
	arch/x86/include/asm/setup.h
	kernel/irq/handle.c

Semantic merge:
        arch/x86/include/asm/fixmap.h

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-27 17:28:43 +01:00
Rusty Russell 6db6a5f3ae lguest: fix for CONFIG_SPARSE_IRQ=y
Impact: remove lots of lguest boot WARN_ON() when CONFIG_SPARSE_IRQ=y

We now need to call irq_to_desc_alloc_cpu() before
set_irq_chip_and_handler_name(), but we can't do that from init_IRQ (no
kmalloc available).

So do it as we use interrupts instead.  Also means we only alloc for
irqs we use, which was the intent of CONFIG_SPARSE_IRQ anyway.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
2009-03-09 10:06:29 +10:30
Ingo Molnar 965c7ecaf2 x86: remove the Voyager 32-bit subarch
Impact: remove unused/broken code

The Voyager subarch last built successfully on the v2.6.26 kernel
and has been stale since then and does not build on the v2.6.27,
v2.6.28 and v2.6.29-rc5 kernels.

No actual users beyond the maintainer reported this breakage.
Patches were sent and most of the fixes were accepted but the
discussion around how to do a few remaining issues cleanly
fizzled out with no resolution and the code remained broken.

In the v2.6.30 x86 tree development cycle 32-bit subarch support
has been reworked and removed - and the Voyager code, beyond the
build problems already known, needs serious and significant
changes and probably a rewrite to support it.

CONFIG_X86_VOYAGER has been marked BROKEN then. The maintainer has
been notified but no patches have been sent so far to fix it.

While all other subarchs have been converted to the new scheme,
voyager is still broken. We'd prefer to receive patches which
clean up the current situation in a constructive way, but even in
case of removal there is no obstacle to add that support back
after the issues have been sorted out in a mutually acceptable
fashion.

So remove this inactive code for now.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-23 00:54:01 +01:00
Mark Wallis 05dfdbbd67 lguest: Fix a memory leak with the lg object during launcher close
Fix a memory leak identified by Rusty Russell during LCA09 by
kfree'ing the lg object instead of just clearing it when the
launcher closes.

Signed-off-by: Mark Wallis <mwallis@serialmonkey.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-30 11:34:11 +10:30
Atsushi SAKAI 72410af921 lguest: typos fix
3 points

lguest_asm.S => i386_head.S
LHCALL_BREAK => LHREQ_BREAK
perferred    => preferred

Signed-off-by: Atsushi SAKAI <sakaia@jp.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-30 11:34:10 +10:30
Mark McLoughlin ff8561c4ad lguest: do not statically allocate root device
We shouldn't be statically allocating the root device object,
so dynamically allocate it using root_device_register()
instead.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-06 10:44:34 -08:00
Linus Torvalds b840d79631 Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits)
  x86: export vector_used_by_percpu_irq
  x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and()
  sched: nominate preferred wakeup cpu, fix
  x86: fix lguest used_vectors breakage, -v2
  x86: fix warning in arch/x86/kernel/io_apic.c
  sched: fix warning in kernel/sched.c
  sched: move test_sd_parent() to an SMP section of sched.h
  sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0
  sched: activate active load balancing in new idle cpus
  sched: bias task wakeups to preferred semi-idle packages
  sched: nominate preferred wakeup cpu
  sched: favour lower logical cpu number for sched_mc balance
  sched: framework for sched_mc/smt_power_savings=N
  sched: convert BALANCE_FOR_xx_POWER to inline functions
  x86: use possible_cpus=NUM to extend the possible cpus allowed
  x86: fix cpu_mask_to_apicid_and to include cpu_online_mask
  x86: update io_apic.c to the new cpumask code
  x86: Introduce topology_core_cpumask()/topology_thread_cpumask()
  x86: xen: use smp_call_function_many()
  x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c
  ...

Fixed up trivial conflict in kernel/time/tick-sched.c manually
2009-01-02 11:44:09 -08:00
Mark McLoughlin bda53cd510 lguest: struct device - replace bus_id with dev_name()
bus_id is gradually being removed, so use dev_name() instead.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30 09:26:12 +10:30
Matias Zabaljauregui 58a2456644 lguest: move the initial guest page table creation code to the host
This patch moves the initial guest page table creation code to the host,
so the launcher keeps working with PAE enabled configs.

Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30 09:26:11 +10:30
Rusty Russell 87c7d57c17 virtio: hand virtio ring alignment as argument to vring_new_virtqueue
This allows each virtio user to hand in the alignment appropriate to
their virtio_ring structures.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
2008-12-30 09:26:03 +10:30
Rusty Russell 2966af73e7 virtio: use LGUEST_VRING_ALIGN instead of relying on pagesize
This doesn't really matter, since lguest is i386 only at the moment,
but we could actually choose a different value.  (lguest doesn't have
a guarenteed ABI).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30 09:26:02 +10:30
Yinghai Lu b77b881f21 x86: fix lguest used_vectors breakage, -v2
Impact: fix lguest, clean up

32-bit lguest used used_vectors to record vectors, but that model of
allocating vectors changed and got broken, after we changed vector
allocation to a per_cpu array.

Try enable that for 64bit, and the array is used for all vectors that
are not managed by vector_irq per_cpu array.

Also kill system_vectors[], that is now a duplication of the
used_vectors bitmap.

[ merged in cpus4096 due to io_apic.c cpumask changes. ]
[ -v2, fix build failure ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-23 22:37:28 +01:00
Rusty Russell 1dc3e3bcbf lguest: update commentry
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-08-26 00:19:28 +10:00
Rusty Russell 71a3f4edc1 lguest: use get_user_pages_fast() instead of get_user_pages()
Using a simple page table thrashing program I measure a slight
improvement.  The program creates five processes.  Each touches 1000
pages then schedules the next process.  We repeat this 1000 times.  As
lguest only caches 4 cr3 values, this rebuilds a lot of shadow page
tables requiring virt->phys mappings.

	Before: 5.93 seconds
	After: 5.40 seconds

(Counts of slow vs fastpath in this usage are 6092 and 2852462 respectively.)

And more importantly for lguest, the code is simpler.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-08-12 17:52:53 +10:00
Andrew Morton cf485e566b lguest: use cpu capability accessors
To support my little make-x86-bitops-use-proper-typechecking projectlet.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrea Arcangeli <andrea@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29 09:58:34 +10:00
Johannes Weiner 0a707210aa lguest: fix switcher_page leak on unload
map_switcher allocates the array, unmap_switcher has to free it
accordingly.

Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29 09:58:32 +10:00
Rusty Russell 0c12091d82 lguest: Guest int3 fix
Ron Minnich noticed that guest userspace gets a GPF when it tries to int3:
we need to copy the privilege level from the guest-supplied IDT to the real
IDT.  int3 is the only common case where guest userspace expects to invoke
an interrupt, so that's the symptom of failing to do this.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29 09:58:31 +10:00
Rusty Russell e34f872567 virtio: Add transport feature handling stub for virtio_ring.
To prepare for virtio_ring transport feature bits, hook in a call in
all the users to manipulate them.  This currently just clears all the
bits, since it doesn't understand any features.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25 12:06:14 +10:00
Rusty Russell c624896e48 virtio: Rename set_features to finalize_features
Rather than explicitly handing the features to the lower-level, we just
hand the virtio_device and have it set the features.  This make it clear
that it has the chance to manipulate the features of the device at this
point (and that all feature negotiation is already done).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25 12:06:12 +10:00
Ingo Molnar 1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Ingo Molnar 15e551d25e x86, VisWS: turn into generic arch, eliminate Kconfig specials
remove leftover traces of various VISWS related Kconfig specials.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-10 18:55:47 +02:00
Jens Axboe 15c8b6c1aa on_each_cpu(): kill unused 'retry' parameter
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:38 +02:00
Ingo Molnar d02859ecb3 Merge commit 'v2.6.26-rc8' into x86/xen
Conflicts:

	arch/x86/xen/enlighten.c
	arch/x86/xen/mmu.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-25 12:16:51 +02:00
Suresh Siddha 54481cf88b x86: fix NULL pointer deref in __switch_to
I am able to reproduce the oops reported by Simon in __switch_to() with
lguest.

My debug showed that there is at least one lguest specific
issue (which should be present in 2.6.25 and before aswell) and it got
exposed with a kernel oops with the recent fpu dynamic allocation patches.

In addition to the previous possible scenario (with fpu_counter), in the
presence of lguest, it is possible that the cpu's TS bit it still set and the
lguest launcher task's thread_info has TS_USEDFPU still set.

This is because of the way the lguest launcher handling the guest's TS bit.
(look at lguest_set_ts() in lguest_arch_run_guest()). This can result
in a DNA fault while doing unlazy_fpu() in __switch_to(). This will
end up causing a DNA fault in the context of new process thats
getting context switched in (as opossed to handling DNA fault in the context
of lguest launcher/helper process).

This is wrong in both pre and post 2.6.25 kernels. In the recent
2.6.26-rc series, this is showing up as NULL pointer dereferences or
sleeping function called from atomic context(__switch_to()), as
we free and dynamically allocate the FPU context for the newly
created threads. Older kernels might show some FPU corruption for processes
running inside of lguest.

With the appended patch, my test system is running for more than 50 mins
now. So atleast some of your oops (hopefully all!) should get fixed.
Please give it a try. I will spend more time with this fix tomorrow.

Reported-by: Simon Holm Thøgersen <odie@cs.aau.dk>
Reported-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-20 13:26:18 +02:00