iommu: remove fullflush and nofullflush in IOMMU generic option

This patch against tip/x86/iommu virtually reverts
2842e5bf3115193f05dc9dac20f940e7abf44c1a. But just reverting the
commit breaks AMD IOMMU so this patch also includes some fixes.

The above commit adds new two options to x86 IOMMU generic kernel boot
options, fullflush and nofullflush. But such change that affects all
the IOMMUs needs more discussion (all IOMMU parties need the chance to
discuss it):

http://lkml.org/lkml/2008/9/19/106

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 7 insertions, 4 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 40066ceb48fe..040ce30632b5 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -284,6 +284,11 @@ and is between 256 and 4096 characters. It is defined in the file
                         isolate - enable device isolation (each device, as far
                                   as possible, will get its own protection
                                   domain)
+                        fullflush - enable flushing of IO/TLB entries when
+                                    they are unmapped. Otherwise they are
+                                    flushed before they will be reused, which
+                                    is a lot of faster
+
         amd_iommu_size= [HW,X86-64]
                         Define the size of the aperture for the AMD IOMMU
                         driver. Possible values are:
@@ -893,10 +898,6 @@ and is between 256 and 4096 characters. It is defined in the file
                 nomerge
                 forcesac
                 soft
-                fullflush
-                        Flush IO/TLB at every deallocation
-                nofullflush
-                        Flush IO/TLB only when addresses are reused (default)
 
 
         intel_iommu=    [DMAR] Intel IOMMU driver (DMAR) option
diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt
index c83c8e4bc8e5..b0c7b6c4abda 100644
--- a/Documentation/x86/x86_64/boot-options.txt
+++ b/Documentation/x86/x86_64/boot-options.txt
@@ -233,6 +233,8 @@ IOMMU (input/output memory management unit)
   iommu options only relevant to the AMD GART hardware IOMMU:
     <size>             Set the size of the remapping area in bytes.
     allowed            Overwrite iommu off workarounds for specific chipsets.
+    fullflush          Flush IOMMU on each allocation (default).
+    nofullflush        Don't use IOMMU fullflush.
     leak               Turn on simple iommu leak tracing (only when
                        CONFIG_IOMMU_LEAK is on). Default number of leak pages
                        is 20.