| Message ID | 1410487848-6027-5-git-send-email-jiang.liu@linux.intel.com |
|---|---|
| State | Not Applicable |
| Headers | show |
On 2014/9/12 10:10, Jiang Liu wrote: > According to Intel VT-d specification, _DSM method to support DMAR > hotplug should exist directly under corresponding ACPI object > representing PCI host bridge. But some BIOSes doesn't conform to > this, so search for _DSM method in the subtree starting from the > ACPI object representing the PCI host bridge. Reviewed-by: Yijing Wang <wangyijing@huawei.com> > > Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> > --- > drivers/iommu/dmar.c | 35 +++++++++++++++++++++++++++++++---- > 1 file changed, 31 insertions(+), 4 deletions(-) > > diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c > index e77b5d3f2f5c..df2c2591c1a6 100644 > --- a/drivers/iommu/dmar.c > +++ b/drivers/iommu/dmar.c > @@ -1926,21 +1926,48 @@ static int dmar_hotplug_remove(acpi_handle handle) > return ret; > } > > -static int dmar_device_hotplug(acpi_handle handle, bool insert) > +static acpi_status dmar_get_dsm_handle(acpi_handle handle, u32 lvl, > + void *context, void **retval) > +{ > + acpi_handle *phdl = retval; > + > + if (dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) { > + *phdl = handle; > + return AE_CTRL_TERMINATE; > + } > + > + return AE_OK; > +} > + > +int dmar_device_hotplug(acpi_handle handle, bool insert) > { > int ret; > + acpi_handle tmp = NULL; > + acpi_status status; > > if (!dmar_in_use()) > return 0; > > - if (!dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) > + if (dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) { > + tmp = handle; > + } else { > + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, > + ACPI_UINT32_MAX, > + dmar_get_dsm_handle, > + NULL, NULL, &tmp); > + if (ACPI_FAILURE(status)) { > + pr_warn("Failed to locate _DSM method.\n"); > + return -ENXIO; > + } > + } > + if (tmp == NULL) > return 0; > > down_write(&dmar_global_lock); > if (insert) > - ret = dmar_hotplug_insert(handle); > + ret = dmar_hotplug_insert(tmp); > else > - ret = dmar_hotplug_remove(handle); > + ret = dmar_hotplug_remove(tmp); > up_write(&dmar_global_lock); > > return ret; >
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index e77b5d3f2f5c..df2c2591c1a6 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -1926,21 +1926,48 @@ static int dmar_hotplug_remove(acpi_handle handle) return ret; } -static int dmar_device_hotplug(acpi_handle handle, bool insert) +static acpi_status dmar_get_dsm_handle(acpi_handle handle, u32 lvl, + void *context, void **retval) +{ + acpi_handle *phdl = retval; + + if (dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) { + *phdl = handle; + return AE_CTRL_TERMINATE; + } + + return AE_OK; +} + +int dmar_device_hotplug(acpi_handle handle, bool insert) { int ret; + acpi_handle tmp = NULL; + acpi_status status; if (!dmar_in_use()) return 0; - if (!dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) + if (dmar_detect_dsm(handle, DMAR_DSM_FUNC_DRHD)) { + tmp = handle; + } else { + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, + ACPI_UINT32_MAX, + dmar_get_dsm_handle, + NULL, NULL, &tmp); + if (ACPI_FAILURE(status)) { + pr_warn("Failed to locate _DSM method.\n"); + return -ENXIO; + } + } + if (tmp == NULL) return 0; down_write(&dmar_global_lock); if (insert) - ret = dmar_hotplug_insert(handle); + ret = dmar_hotplug_insert(tmp); else - ret = dmar_hotplug_remove(handle); + ret = dmar_hotplug_remove(tmp); up_write(&dmar_global_lock); return ret;
According to Intel VT-d specification, _DSM method to support DMAR hotplug should exist directly under corresponding ACPI object representing PCI host bridge. But some BIOSes doesn't conform to this, so search for _DSM method in the subtree starting from the ACPI object representing the PCI host bridge. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> --- drivers/iommu/dmar.c | 35 +++++++++++++++++++++++++++++++---- 1 file changed, 31 insertions(+), 4 deletions(-)