diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-23 18:54:23 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-23 18:54:23 -0700 |
commit | 83c7f72259ea4bd0561e2f2762d97ee2888126ce (patch) | |
tree | c8b181e9f9a0bb061f5ab63fabb98197d7aee19a /arch/powerpc/lib/vmx-helper.c | |
parent | e05644e17e744315bce12b0948cdc36910b9a76e (diff) | |
parent | 574ce79cea9d3fda109ffcc82f81733de4740e5c (diff) |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc updates from Benjamin Herrenschmidt:
"Notable highlights:
- iommu improvements from Anton removing the per-iommu global lock in
favor of dividing the DMA space into pools, each with its own lock,
and hashed on the CPU number. Along with making the locking more
fine grained, this gives significant improvements in multiqueue
networking scalability.
- Still from Anton, we know provide a vdso based variant of getcpu
which makes sched_getcpu with the appropriate glibc patch something
like 18 times faster.
- More anton goodness (he's been busy !) in other areas such as a
faster __clear_user and copy_page on P7, various perf fixes to
improve sampling quality, etc...
- One more step toward removing legacy i2c interfaces by using new
device-tree based probing of platform devices for the AOA audio
drivers
- A nice series of patches from Michael Neuling that helps avoiding
confusion between register numbers and litterals in assembly code,
trying to enforce the use of "%rN" register names in gas rather
than plain numbers.
- A pile of FSL updates
- The usual bunch of small fixes, cleanups etc...
You may spot a change to drivers/char/mem. The patch got no comment
or ack from outside, it's a trivial patch to allow the architecture to
skip creating /dev/port, which we use to disable it on ppc64 that
don't have a legacy brige. On those, IO ports 0...64K are not mapped
in kernel space at all, so accesses to /dev/port cause oopses (and
yes, distros -still- ship userspace that bangs hard coded ports such
as kbdrate)."
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (106 commits)
powerpc/mpic: Create a revmap with enough entries for IPIs and timers
Remove stale .rej file
powerpc/iommu: Fix iommu pool initialization
powerpc/eeh: Check handle_eeh_events() return value
powerpc/85xx: Add phy nodes in SGMII mode for MPC8536/44/72DS & P2020DS
powerpc/e500: add paravirt QEMU platform
powerpc/mpc85xx_ds: convert to unified PCI init
powerpc/fsl-pci: get PCI init out of board files
powerpc/85xx: Update corenet64_smp_defconfig
powerpc/85xx: Update corenet32_smp_defconfig
powerpc/85xx: Rename P1021RDB-PC device trees to be consistent
powerpc/watchdog: move booke watchdog param related code to setup-common.c
sound/aoa: Adapt to new i2c probing scheme
i2c/powermac: Improve detection of devices from device-tree
powerpc: Disable /dev/port interface on systems without an ISA bridge
of: Improve prom_update_property() function
powerpc: Add "memory" attribute for mfmsr()
powerpc/ftrace: Fix assembly trampoline register usage
powerpc/hw_breakpoints: Fix incorrect pointer access
powerpc: Put the gpr save/restore functions in their own section
...
Diffstat (limited to 'arch/powerpc/lib/vmx-helper.c')
-rw-r--r-- | arch/powerpc/lib/vmx-helper.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/arch/powerpc/lib/vmx-helper.c b/arch/powerpc/lib/vmx-helper.c new file mode 100644 index 00000000000..3cf529ceec5 --- /dev/null +++ b/arch/powerpc/lib/vmx-helper.c @@ -0,0 +1,74 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2011 + * + * Authors: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> + * Anton Blanchard <anton@au.ibm.com> + */ +#include <linux/uaccess.h> +#include <linux/hardirq.h> +#include <asm/switch_to.h> + +int enter_vmx_usercopy(void) +{ + if (in_interrupt()) + return 0; + + /* This acts as preempt_disable() as well and will make + * enable_kernel_altivec(). We need to disable page faults + * as they can call schedule and thus make us lose the VMX + * context. So on page faults, we just fail which will cause + * a fallback to the normal non-vmx copy. + */ + pagefault_disable(); + + enable_kernel_altivec(); + + return 1; +} + +/* + * This function must return 0 because we tail call optimise when calling + * from __copy_tofrom_user_power7 which returns 0 on success. + */ +int exit_vmx_usercopy(void) +{ + pagefault_enable(); + return 0; +} + +int enter_vmx_copy(void) +{ + if (in_interrupt()) + return 0; + + preempt_disable(); + + enable_kernel_altivec(); + + return 1; +} + +/* + * All calls to this function will be optimised into tail calls. We are + * passed a pointer to the destination which we return as required by a + * memcpy implementation. + */ +void *exit_vmx_copy(void *dest) +{ + preempt_enable(); + return dest; +} |