2013-07-18 02:46:35

by Ren Qiaowei

Subject: [PATCH v2] x86, tboot: iomem fixes

Fixes for iomem annotations in arch/x86/kernel/tboot.c

Signed-off-by: Qiaowei Ren <[email protected]>
---
arch/x86/kernel/tboot.c | 21 ++++++++++++---------
1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index 3ff42d2..afe8cf8 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -466,9 +466,12 @@ struct sinit_mle_data {
u32 vtd_dmars_off;
} __packed;

+#define SINIT_MLE_DATA_VTD_DMAR_OFF 140
+
struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
{
- void *heap_base, *heap_ptr, *config;
+ void __iomem *heap_base, *heap_ptr, *config;
+ u32 dmar_tbl_off;

if (!tboot_enabled())
return dmar_tbl;
@@ -485,25 +488,25 @@ struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tb
return NULL;

/* now map TXT heap */
- heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
- *(u64 *)(config + TXTCR_HEAP_SIZE));
+ heap_base = ioremap(readl(config + TXTCR_HEAP_BASE),
+ readl(config + TXTCR_HEAP_SIZE));
iounmap(config);
if (!heap_base)
return NULL;

/* walk heap to SinitMleData */
/* skip BiosData */
- heap_ptr = heap_base + *(u64 *)heap_base;
+ heap_ptr = heap_base + readq(heap_base);
/* skip OsMleData */
- heap_ptr += *(u64 *)heap_ptr;
+ heap_ptr += readq(heap_ptr);
/* skip OsSinitData */
- heap_ptr += *(u64 *)heap_ptr;
+ heap_ptr += readq(heap_ptr);
/* now points to SinitMleDataSize; set to SinitMleData */
heap_ptr += sizeof(u64);
/* get addr of DMAR table */
- dmar_tbl = (struct acpi_table_header *)(heap_ptr +
- ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
- sizeof(u64));
+ dmar_tbl_off = readl(heap_ptr + SINIT_MLE_DATA_VTD_DMAR_OFF);
+ memcpy_fromio(dmar_tbl, heap_ptr + dmar_tbl_off - sizeof(u64),
+ sizeof(struct acpi_table_header));

/* don't unmap heap because dmar.c needs access to this */

--
1.7.9.5

2013-07-18 07:01:51

by Ingo Molnar

Subject: Re: [PATCH v2] x86, tboot: iomem fixes

* Qiaowei Ren <[email protected]> wrote:

> Fixes for iomem annotations in arch/x86/kernel/tboot.c
>
> Signed-off-by: Qiaowei Ren <[email protected]>
> ---
> arch/x86/kernel/tboot.c | 21 ++++++++++++---------
> 1 file changed, 12 insertions(+), 9 deletions(-)
>
> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
> index 3ff42d2..afe8cf8 100644
> --- a/arch/x86/kernel/tboot.c
> +++ b/arch/x86/kernel/tboot.c
> @@ -466,9 +466,12 @@ struct sinit_mle_data {
> u32 vtd_dmars_off;
> } __packed;
>
> +#define SINIT_MLE_DATA_VTD_DMAR_OFF 140
> +
> struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
> {
> - void *heap_base, *heap_ptr, *config;
> + void __iomem *heap_base, *heap_ptr, *config;
> + u32 dmar_tbl_off;
>
> if (!tboot_enabled())
> return dmar_tbl;
> @@ -485,25 +488,25 @@ struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tb
> return NULL;
>
> /* now map TXT heap */
> - heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
> - *(u64 *)(config + TXTCR_HEAP_SIZE));
> + heap_base = ioremap(readl(config + TXTCR_HEAP_BASE),
> + readl(config + TXTCR_HEAP_SIZE));
> iounmap(config);
> if (!heap_base)
> return NULL;
>
> /* walk heap to SinitMleData */
> /* skip BiosData */
> - heap_ptr = heap_base + *(u64 *)heap_base;
> + heap_ptr = heap_base + readq(heap_base);
> /* skip OsMleData */
> - heap_ptr += *(u64 *)heap_ptr;
> + heap_ptr += readq(heap_ptr);
> /* skip OsSinitData */
> - heap_ptr += *(u64 *)heap_ptr;
> + heap_ptr += readq(heap_ptr);
> /* now points to SinitMleDataSize; set to SinitMleData */
> heap_ptr += sizeof(u64);
> /* get addr of DMAR table */
> - dmar_tbl = (struct acpi_table_header *)(heap_ptr +
> - ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
> - sizeof(u64));
> + dmar_tbl_off = readl(heap_ptr + SINIT_MLE_DATA_VTD_DMAR_OFF);
> + memcpy_fromio(dmar_tbl, heap_ptr + dmar_tbl_off - sizeof(u64),
> + sizeof(struct acpi_table_header));

The changelog is not sufficient, as this change is clearly not just about
annotations: that memcpy_fromio() call is new.

Please use the customary changelog style we use in the kernel:

" Current code does (A), this has a problem when (B).
We can improve this doing (C), because (D)."

Thanks,

Ingo