Commit Graph

27323 Commits

Author SHA1 Message Date
Geoff Levand
540270d82d [POWERPC] spufs: further abstract priv1 register access
To support muti-platform binaries the spu hypervisor accessor
routines must have runtime binding.

I removed the existing statically linked routines in spu.h
and spu_priv1_mmio.c and created new accessor routines in spu_priv1.h
that operate indirectly through an ops struct spu_priv1_ops.
spu_priv1_mmio.c contains the instance of the accessor routines
for running on raw hardware.

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:31 +10:00
Geoff Levand
c01ea72a3b [POWERPC] spufs: split the Cell BE support into generic and platform dependant parts
Creates new config variables PPC_CELL_NATIVE and PPC_IBM_CELL_BLADE.
The existing CONFIG_PPC_CELL is now used to denote the generic
Cell processor support.

PPC_CELL = make descends into platforms/cell
PPC_CELL_NATIVE = add bare metal support
PPC_IBM_CELL_BLADE = add blade device drivers, etc.

Also renames spu_priv1.c to spu_priv1_mmio.c.

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:31 +10:00
arnd@arndb.de
e46a0237fd [POWERPC] spufs: dont try to access SPE channel 1 count
The save/restore sequence for SPE contexts currently attempts to save
and restore the channel count for SPE channel 1 (the SPU_WriteEventMask
channel.  But the CBE architecture (section 9.11.2) clearly states
that this channel does not have an associated count.  Hardware simply
ignores the attempt to write this count, but the simulator generates
a warning message.

WARNING: 279721590: SPE7: Attempt to write channel count for CH 1 with
no associated count is ignored.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:31 +10:00
Jeremy Kerr
ecec21770d [POWERPC] spufs: use kzalloc in create_spu
Clean up create_spu() a little by using kzalloc instead of kmalloc +
assignments.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:30 +10:00
arnd@arndb.de
970f1baae7 [POWERPC] spufs: fix initial state of wbox file
The wbox channel count of an spu is now initialized
to four for the saved context. This makes it possible
to write to the mailbox right away without waiting
for the SPE to become scheduled first.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:30 +10:00
arnd@arndb.de
7b1a701480 [POWERPC] spufs: add a phys-id attribute to each SPU context
For performance analysis, it is often interesting to know
which physical SPE a thread is currently running on, and,
more importantly, if it is running at all.

This patch adds a simple attribute to each SPU directory
with that information.
The attribute is read-only and called 'phys-id'. It contains
an ascii string with the number of the physical SPU (e.g.
"0x5"), or alternatively the string "0xffffffff" (32 bit -1)
when it is not running at all at the time that the file
is read.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:30 +10:00
arnd@arndb.de
724bd80e81 [POWERPC] spufs: set up correct SLB entries for 64k pages
spufs currently knows only 4k pages and 16M hugetlb
pages. Make it use the regular methods for deciding on
the SLB bits.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:30 +10:00
Michael Ellerman
0309f02d8e [POWERPC] spufs: fix deadlock in spu_create error path
spufs_rmdir tries to acquire the spufs root
i_mutex, which is already held by spufs_create_thread.

This was tracked as Bug #H9512.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:30 +10:00
arnd@arndb.de
d9379c4bce [POWERPC] spufs: restore mapping of mssync register
A recent change to the way that the mfc file gets mapped made it
impossible to map the SPE Multi-Source Synchronization register
into user space, but that may be needed by some applications.

This restores the missing functionality.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:30 +10:00
arnd@arndb.de
91edfa49b9 [POWERPC] cell: always build spu base into the kernel
The spu_base module is rather deeply intermixed with the
core kernel, so it makes sense to have that built-in.
This will let us extend the base in the future without
having to export more core symbols just for it.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:30 +10:00
Jeremy Kerr
1d64093f66 [POWERPC] cell: register SPUs as sysdevs
SPUs are registered as system devices, exposing attributes through
sysfs. Since the sysdev includes a kref, we can remove the one in
struct spu (it isn't used at the moment anyway).

Currently only the interrupt source and numa node attributes are added.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:29 +10:00
arnd@arndb.de
0f0f90c304 [POWERPC] cell: update defconfig
Enable some of the most requested features in defconfig
and refresh with the latest powerpc.git Kconfig files.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:29 +10:00
arnd@arndb.de
b40feec8ef [POWERPC] cell: fix interrupt priority handling
Checking the priority field to test for irq validity is
completely bogus and breaks with future external interrupt
controllers.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:29 +10:00
Benjamin Herrenschmidt
acf7d76827 [POWERPC] cell: add RAS support
This is a first version of support for the Cell BE "Reliability,
Availability and Serviceability" features.

It doesn't yet handle some of the RAS interrupts (the ones described in
iic_is/iic_irr), I'm still working on a proper way to expose these. They
are essentially a cascaded controller by themselves (sic !) though I may
just handle them locally to the iic driver. I need also to sync with
David Erb on the way he hooked in the performance monitor interrupt.

So that's all for 2.6.17 and I'll do more work on that with my rework of
the powerpc interrupt layer that I'm hacking on at the moment.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:29 +10:00
Jon Loeliger
ef82a306b4 [POWERPC] Add Vitesse 8244 PHY for MPC8641 HPCN platform.
Signed-off-by: Kriston Carson <KristonCarson@freescale.com>
Signed-off-by: Xianghua Xiao <x.xiao@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:29 +10:00
Jon Loeliger
2097c7f04a [POWERPC] Document I2C_MPC option for 86xx too.
The same I2C driver found on 85xx, etc., can be used for 86xx too.

Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:29 +10:00
Jon Loeliger
6b54340405 [POWERPC] Add 8641 Register space and IRQ definitions.
Signed-off-by: Jeff Brown <Jeff.Brown@freescale.com>
Signed-off-by: Xianghua Xiao <x.xiao@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:28 +10:00
Jon Loeliger
b809b3e86f [POWERPC] Add mpc8641hpcn PCI/PCI-Express platform files.
Signed-off-by: Xianghua Xiao <x.xiao@freescale.com>
Signed-off-by: Wei Zhang <Wei.Zhang@freescale.com>
Signed-off-by: Haiying Wang <Haiying.Wang@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:28 +10:00
Jon Loeliger
4ca4b6274c [POWERPC] Add the MPC8641 HPCN platform files.
Signed-off-by: Xianghua Xiao <x.xiao@freescale.com>
Signed-off-by: Haiying Wang <Haiying.Wang@freescale.com>
Signed-off-by: Wei Zhang <Wei.Zhang@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:28 +10:00
Jon Loeliger
ee0339f205 [POWERPC] Add starting of secondary 86xx CPUs.
Clear the high BATS during load_up_mmu if FTR_HAS_HIGH_BATS.
Allow just a bit more time for secondary CPUs to phone home.

Signed-off-by: Wei Zhang <Wei.Zhang@freescale.com>
Signed-off-by: Haiying Wang <Haiying.Wang@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:28 +10:00
Jon Loeliger
9674ed38d8 [POWERPC] Add 8641 CPU table entry.
Signed-off-by: Wei Zhang <Wei.Zhang@freescale.com>
Signed-off-by: Xianghua Xiao <x.xiao@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:28 +10:00
Jon Loeliger
96abe9358b [POWERPC] Add mpc8641_hpcn_defconfig config file.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Haiying Wang <Haiying.Wang@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:28 +10:00
Jon Loeliger
c9b484b5c1 [POWERPC] Add the mpc8641 hpcn Kconfig and Makefiles.
Signed-off-by: Xianghua Xiao <x.xiao@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:27 +10:00
Jon Loeliger
8a30088794 [POWERPC] Prevent duplicate lmb reservations for Device Tree blob.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:27 +10:00
Jon Loeliger
2198c07049 [POWERPC] Guard L3CR references with CPU_FTR_L3CR.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:27 +10:00
John Rose
7932f0b82f [POWERPC] RTAS delay, fix module build breaks
Export both news RTAS delay functions, and change the scanlog module to
use the new delay functions.

Signed-off-by: John Rose <johnrose@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-21 15:01:27 +10:00
Matthias Fuchs
2ba73b1d6f [POWERPC] ppc32: fix CPCI405 board support
Hi,

this patch brings the CPCI405 board support up to date and fixes several
outstanding issues:

       -add bios_fixup()
       -enable RTC only when CONFIG_GEN_RTC defined
       -corrected CompactPCI interrupt map
       -added cpci405_early_serial_map for correct UART clocking
       -removed unused code

Matthias

Signed-off-by: Matthias Fuchs <matthias.fuchs@esd-electronics.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:27 +10:00
Johannes Berg
4312dc76a8 [POWERPC] make pmf irq_client functions safe against pmf interrupts coming in
This fixes the pmf irq_client functions to be safe against pmf interrupts coming
in while a client is registered/unregistered.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:27 +10:00
Dave C Boutcher
368a6ba5d1 [POWERPC] check firmware state before suspending
Currently the kernel blindly halts all the processors and calls the
ibm,suspend-me rtas call.  If the firmware is not in the correct
state, we then re-start all the processors and return.  It is much
smarter to first check the firmware state, and only if it is waiting,
call the ibm,suspend-me call.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:27 +10:00
Amos Waterland
0e4aa9c200 [POWERPC] Fix builtin command line interaction with firmware
It seems that prom_init's early_cmdline_parse is broken on at least
Apple 970 xserves and IBM JS20 blades with SLOF.  The firmware of these
machines returns -1 and 1 respectively when getprop is called for the
bootargs property of /chosen, causing Linux to ignore its builtin
command line in favor of a null string.  This patch makes Linux use its
builtin command line if getprop returns an error or a null string.

Signed-off-by: Amos Waterland <apw@us.ibm.com>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
6fe8767531 [POWERPC] update pmac32_defconfig
Some updates to the pmac32_defconfig to make it more useful:

- Enable LSF (large single files) since we enable LBD (large block devices)
- Enable IPSEC related options
- Enable remaining raid/dm options as modules
- Disable eth1394, I doubt any has that hardware and it has a nasty habit of
  auto loading first and skewing network device numbering
- Enable dummy and tun as modules, always useful to have them around
- Enable EHCI, no wonder my usb2 disk was so slow
- Enable USB storage
- Enable ext3 acls
- Disable autofs and enable autofsv4 instead
- Enable nfs v3/v4 client and server. Dont want to be left in the dark ages
  of pre v3
- Enable all crypto as modules, things like cryptsetup want some of them

I havent enabled the BCM43xx, perhaps we should now?

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
bd19c8994a [POWERPC] system call micro optimisation
In the syscall path we currently have:

       crclr   so
       mfcr    r9

If we shift the crclr up we can avoid a stall on some CPUs.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
9e6e3c2c79 [POWERPC] Fix HV bit handling on non partitioned machines
On non partitioned machines we currently set the HV bit in kernel space
only. It turns out we are supposed to maintain the HV bit in both user
and kernel space.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
df310656c7 [POWERPC] cleanup dma_mapping_ops
For pseries IOMMU bypass I want to be able to fall back to the regular
IOMMU ops. Do this by creating a dma_mapping_ops struct, and convert
the others while at it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
ca1588e71b [POWERPC] node local IOMMU tables
Allocate IOMMU tables local to the relevant node.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
357518fa34 [POWERPC] pcibus_to_node fixes
of_node_to_nid returns -1 if the associativity cannot be found. This
means pcibus_to_cpumask has to be careful not to pass a negative index into
node_to_cpumask.

Since pcibus_to_node could be used a lot, and of_node_to_nid is slow (it
walks a list doing strcmps), lets also cache the node in the
pci_controller struct.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
f2b09c8189 [POWERPC] Update pseries defconfig
pseries defconfig updates:

- Enable jsm and re-enable qlogic FC drivers as modules.
- Enable ocfs2, autofs4 and fuse filesystems as modules.
- Enable Kprobes.
- Enable ebus, binfmt_misc, sas attrs, md5 reshape, hvc rtas backend and
  some infiniband options.
- Finally disable debug options: DEBUG_MUTEXES and DEBUG_STACK_USAGE.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
227318bbde [POWERPC] Remove stale 64bit on 32bit kernel code
Remove some stale POWER3/POWER4/970 on 32bit kernel support.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:26 +10:00
Anton Blanchard
8555a0029b [POWERPC] Optimise some TOC usage
Micro-optimisation - add no-minimal-toc to some more arch/powerpc Makefiles.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:25 +10:00
Anton Blanchard
3a2c48cfc9 [POWERPC] 64bit FPSCR support
Forthcoming machines will extend the FPSCR to 64 bits.  We already
had a 64-bit save area for the FPSCR, but we need to use a new form
of the mtfsf instruction.  Fortunately this new form is decoded as
an ordinary mtfsf by existing 64-bit processors.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:25 +10:00
mostrows@watson.ibm.com
30d8caf7c6 [POWERPC] Editable kernel command-line in zImage binary.
zImage will set /chosen/bootargs (if it is otherwise empty) with the
contents of a buffer in the section "__builtin_cmdline".  This permits
tools to edit zImage binaries to set the command-line eventually
processed by vmlinux.

--
Signed-off-by: Michal Ostrowski <mostrows@watson.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:25 +10:00
Jake Moilanen
204face4fb [POWERPC] MSI abstraction
Instead of trying to make PPC64 MSI fit in a Intel-centric MSI layer, a
simple short-term solution is to hook the pci_{en/dis}able_msi() calls
and make a machdep call.

The rest of the MSI functions are superfluous for what is needed at this
time.  Many of which can have machdep calls added as needed.

Ben and Michael Ellerman are looking into rewrite the MSI layer to be
more generic.  However, in the meantime this works as a interim
solution.

Signed-off-by: Jake Moilanen <moilanen@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:25 +10:00
Jake Moilanen
bb53bb3dcb [POWERPC] Add support for PCI-Express nodes in the device tree
This adds support to recognize the PCIe device_type "pciex" and made
the portdrv buildable.

Signed-off-by: Jake Moilanen <moilanen@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:31:25 +10:00
Paul Mackerras
0f582bc1f2 powerpc: Simplify push_end definition in pci_32.c
The push_end macro in arch/powerpc/kernel/pci_32.c uses integer
division and multiplication to achieve the effect of rounding a
resource end address up and then advancing it to the end of a
power-of-2 sized region.  This changes it to an equivalent computation
that only needs an integer add and OR.  This is partly based on an
earlier patch by Mel Gorman.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 19:25:50 +10:00
Paul Mackerras
bf72aeba2f powerpc: Use 64k pages without needing cache-inhibited large pages
Some POWER5+ machines can do 64k hardware pages for normal memory but
not for cache-inhibited pages.  This patch lets us use 64k hardware
pages for most user processes on such machines (assuming the kernel
has been configured with CONFIG_PPC_64K_PAGES=y).  User processes
start out using 64k pages and get switched to 4k pages if they use any
non-cacheable mappings.

With this, we use 64k pages for the vmalloc region and 4k pages for
the imalloc region.  If anything creates a non-cacheable mapping in
the vmalloc region, the vmalloc region will get switched to 4k pages.
I don't know of any driver other than the DRM that would do this,
though, and these machines don't have AGP.

When a region gets switched from 64k pages to 4k pages, we do not have
to clear out all the 64k HPTEs from the hash table immediately.  We
use the _PAGE_COMBO bit in the Linux PTE to indicate whether the page
was hashed in as a 64k page or a set of 4k pages.  If hash_page is
trying to insert a 4k page for a Linux PTE and it sees that it has
already been inserted as a 64k page, it first invalidates the 64k HPTE
before inserting the 4k HPTE.  The hash invalidation routines also use
the _PAGE_COMBO bit, to determine whether to look for a 64k HPTE or a
set of 4k HPTEs to remove.  With those two changes, we can tolerate a
mix of 4k and 64k HPTEs in the hash table, and they will all get
removed when the address space is torn down.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 10:45:18 +10:00
Paul Mackerras
31925323b1 powerpc: Fix some missed ppc32 mm->context.id conversions
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-13 13:43:00 +10:00
Paul Mackerras
4306443128 powerpc: Remove unused paca->pgdir field
The pgdir field in the paca was a leftover from the dynamic VSIDs
patch, and is not used in the current kernel code.  This removes it.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-12 18:38:21 +10:00
Paul Mackerras
7a0c58d051 Merge branch 'merge' 2006-06-12 17:53:34 +10:00
Paul Mackerras
289a1e995e [PATCH] Fix for the PPTP hangs that have been reported
People have been reporting that PPP connections over ptys, such as
used with PPTP, will hang randomly when transferring large amounts of
data, for instance in http://bugzilla.kernel.org/show_bug.cgi?id=6530.
I have managed to reproduce the problem, and the patch below fixes the
actual cause.

The problem is not in fact in ppp_async.c but in n_tty.c.  What
happens is that when pptp reads from the pty, we call read_chan() in
drivers/char/n_tty.c on the master side of the pty.  That copies all
the characters out of its buffer to userspace and then calls
check_unthrottle(), which calls the pty unthrottle routine, which
calls tty_wakeup on the slave side, which calls ppp_asynctty_wakeup,
which calls tasklet_schedule.  So far so good.  Since we are in
process context, the tasklet runs immediately and calls
ppp_async_process(), which calls ppp_async_push, which calls the
tty->driver->write function to send some more output.

However, tty->driver->write() returns zero, because the master
tty->receive_room is still zero.  We haven't returned from
check_unthrottle() yet, and read_chan() only updates tty->receive_room
_after_ calling check_unthrottle.  That means that the driver->write
call in ppp_async_process() returns 0.  That would be fine if we were
going to get a subsequent wakeup call, but we aren't (we just had it,
and the buffer is now empty).

The solution is for n_tty.c to update tty->receive_room _before_
calling the driver unthrottle routine.  The patch below does this.
With this patch I was able to transfer a 900MB file over a PPTP
connection (taking about 25 minutes), whereas without the patch the
connection would always stall in under a minute.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-11 20:40:39 -07:00
Linus Torvalds
dc4967e756 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6:
  [PATCH] PCI: reverse pci config space restore order
  [PATCH] PCI: Improve PCI config space writeback
  [PATCH] PCI: Error handling on PCI device resume
  [PATCH] PCI: fix pciehp compile issue when CONFIG_ACPI is not enabled
2006-06-11 15:28:04 -07:00