Merge commit '4cb38750d49010ae72e718d46605ac9ba5a851b4' into stable/for-linus-3.6

* commit '4cb38750d49010ae72e718d46605ac9ba5a851b4': (6849 commits)
  bcma: fix invalid PMU chip control masks
  [libata] pata_cmd64x: whitespace cleanup
  libata-acpi: fix up for acpi_pm_device_sleep_state API
  sata_dwc_460ex: device tree may specify dma_channel
  ahci, trivial: fixed coding style issues related to braces
  ahci_platform: add hibernation callbacks
  libata-eh.c: local functions should not be exposed globally
  libata-transport.c: local functions should not be exposed globally
  sata_dwc_460ex: support hardreset
  ata: use module_pci_driver
  drivers/ata/pata_pcmcia.c: adjust suspicious bit operation
  pata_imx: Convert to clk_prepare_enable/clk_disable_unprepare
  ahci: Enable SB600 64bit DMA on MSI K9AGM2 (MS-7327) v2
  [libata] Prevent interface errors with Seagate FreeAgent GoFlex
  drivers/acpi/glue: revert accidental license-related 6b66d95895c bits
  libata-acpi: add missing inlines in libata.h
  i2c-omap: Add support for I2C_M_STOP message flag
  i2c: Fall back to emulated SMBus if the operation isn't supported natively
  i2c: Add SCCB support
  i2c-tiny-usb: Add support for the Robofuzz OSIF USB/I2C converter
  ...

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;
+}