Re: [PATCH v2] iommu/io-pgtable: Rationalise quirk handling
On Fri, Feb 12, 2016 at 05:09:46PM +, Robin Murphy wrote: > As the number of io-pgtable implementations grows beyond 1, it's time > to rationalise the quirks mechanism before things have a chance to > start getting really ugly and out-of-hand. > > To that end: > - Indicate exactly which quirks each format can/does support. > - Fail creating a table if a caller wants unsupported quirks. > - Properly document where each quirk applies and why. > > Signed-off-by: Robin Murphy > --- > > Just to allay any confusion, I intend this as a followup to the > short-descriptor[1] and Mediatek IOMMU[2] patches, rather than a > crucial addition, so it can either get picked up along with those > or wait 'til later. I'd like to see it included in whichever tree takes the short-descriptor code so, in case that's not my tree: Acked-by: Will Deacon Will ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH v2] iommu/io-pgtable: Rationalise quirk handling
On 12/02/16 17:24, Laurent Pinchart wrote: Hi Robin, Thank you for the patch. On Friday 12 February 2016 17:09:46 Robin Murphy wrote: As the number of io-pgtable implementations grows beyond 1, it's time to rationalise the quirks mechanism before things have a chance to start getting really ugly and out-of-hand. To that end: - Indicate exactly which quirks each format can/does support. - Fail creating a table if a caller wants unsupported quirks. - Properly document where each quirk applies and why. Signed-off-by: Robin Murphy --- Just to allay any confusion, I intend this as a followup to the short-descriptor[1] and Mediatek IOMMU[2] patches, rather than a crucial addition, so it can either get picked up along with those or wait 'til later. v2: - Use unsigned long for the bitmap. - Do format-specific checks inline. - Enough of a difference that I don't feel comfortable putting Laurent's reviewed-by from v1 on it... Here it is again. Reviewed-by: Laurent Pinchart Thanks! Robin. ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH v2] iommu/io-pgtable: Rationalise quirk handling
Hi Robin,
Thank you for the patch.
On Friday 12 February 2016 17:09:46 Robin Murphy wrote:
> As the number of io-pgtable implementations grows beyond 1, it's time
> to rationalise the quirks mechanism before things have a chance to
> start getting really ugly and out-of-hand.
>
> To that end:
> - Indicate exactly which quirks each format can/does support.
> - Fail creating a table if a caller wants unsupported quirks.
> - Properly document where each quirk applies and why.
>
> Signed-off-by: Robin Murphy
> ---
>
> Just to allay any confusion, I intend this as a followup to the
> short-descriptor[1] and Mediatek IOMMU[2] patches, rather than a
> crucial addition, so it can either get picked up along with those
> or wait 'til later.
>
> v2:
> - Use unsigned long for the bitmap.
> - Do format-specific checks inline.
> - Enough of a difference that I don't feel comfortable putting
> Laurent's reviewed-by from v1 on it...
Here it is again.
Reviewed-by: Laurent Pinchart
> [1]:http://thread.gmane.org/gmane.linux.kernel.iommu/12007
> [2]:http://thread.gmane.org/gmane.linux.kernel.iommu/11974
>
> drivers/iommu/io-pgtable-arm-v7s.c | 5 +
> drivers/iommu/io-pgtable-arm.c | 13 +++--
> drivers/iommu/io-pgtable.h | 22 ++
> 3 files changed, 34 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/iommu/io-pgtable-arm-v7s.c
> b/drivers/iommu/io-pgtable-arm-v7s.c index d39a021..9fcceb1 100644
> --- a/drivers/iommu/io-pgtable-arm-v7s.c
> +++ b/drivers/iommu/io-pgtable-arm-v7s.c
> @@ -623,6 +623,11 @@ static struct io_pgtable *arm_v7s_alloc_pgtable(struct
> io_pgtable_cfg *cfg, if (cfg->ias > ARM_V7S_ADDR_BITS || cfg->oas >
> ARM_V7S_ADDR_BITS) return NULL;
>
> + if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
> + IO_PGTABLE_QUIRK_NO_PERMS |
> + IO_PGTABLE_QUIRK_TLBI_ON_MAP))
> + return NULL;
> +
> data = kmalloc(sizeof(*data), GFP_KERNEL);
> if (!data)
> return NULL;
> diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
> index 4095af2..debdf04 100644
> --- a/drivers/iommu/io-pgtable-arm.c
> +++ b/drivers/iommu/io-pgtable-arm.c
> @@ -658,8 +658,12 @@ static struct io_pgtable *
> arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
> {
> u64 reg;
> - struct arm_lpae_io_pgtable *data = arm_lpae_alloc_pgtable(cfg);
> + struct arm_lpae_io_pgtable *data;
>
> + if (cfg->quirks & ~IO_PGTABLE_QUIRK_ARM_NS)
> + return NULL;
> +
> + data = arm_lpae_alloc_pgtable(cfg);
> if (!data)
> return NULL;
>
> @@ -742,8 +746,13 @@ static struct io_pgtable *
> arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
> {
> u64 reg, sl;
> - struct arm_lpae_io_pgtable *data = arm_lpae_alloc_pgtable(cfg);
> + struct arm_lpae_io_pgtable *data;
>
> + /* The NS quirk doesn't apply at stage 2 */
> + if (cfg->quirks)
> + return NULL;
> +
> + data = arm_lpae_alloc_pgtable(cfg);
> if (!data)
> return NULL;
>
> diff --git a/drivers/iommu/io-pgtable.h b/drivers/iommu/io-pgtable.h
> index 4faee7d..d4f5027 100644
> --- a/drivers/iommu/io-pgtable.h
> +++ b/drivers/iommu/io-pgtable.h
> @@ -47,10 +47,24 @@ struct iommu_gather_ops {
> * page table walker.
> */
> struct io_pgtable_cfg {
> - #define IO_PGTABLE_QUIRK_ARM_NS BIT(0) /* Set NS bit in PTEs */
> - #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1) /* No AP/XN bits */
> - #define IO_PGTABLE_QUIRK_TLBI_ON_MAPBIT(2) /* TLB Inv. on map */
> - int quirks;
> + /*
> + * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
> + * stage 1 PTEs, for hardware which insists on validating them
> + * even in non-secure state where they should normally be ignored.
> + *
> + * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
> + * IOMMU_NOEXEC flags and map everything with full access, for
> + * hardware which does not implement the permissions of a given
> + * format, and/or requires some format-specific default value.
> + *
> + * IO_PGTABLE_QUIRK_TLBI_ON_MAP: If the format forbids caching invalid
> + * (unmapped) entries but the hardware might do so anyway, perform
> + * TLB maintenance when mapping as well as when unmapping.
> + */
> + #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
> + #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
> + #define IO_PGTABLE_QUIRK_TLBI_ON_MAPBIT(2)
> + unsigned long quirks;
> unsigned long pgsize_bitmap;
> unsigned intias;
> unsigned intoas;
--
Regards,
Laurent Pinchart
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[PATCH v2] iommu/io-pgtable: Rationalise quirk handling
As the number of io-pgtable implementations grows beyond 1, it's time
to rationalise the quirks mechanism before things have a chance to
start getting really ugly and out-of-hand.
To that end:
- Indicate exactly which quirks each format can/does support.
- Fail creating a table if a caller wants unsupported quirks.
- Properly document where each quirk applies and why.
Signed-off-by: Robin Murphy
---
Just to allay any confusion, I intend this as a followup to the
short-descriptor[1] and Mediatek IOMMU[2] patches, rather than a
crucial addition, so it can either get picked up along with those
or wait 'til later.
v2:
- Use unsigned long for the bitmap.
- Do format-specific checks inline.
- Enough of a difference that I don't feel comfortable putting
Laurent's reviewed-by from v1 on it...
Robin.
[1]:http://thread.gmane.org/gmane.linux.kernel.iommu/12007
[2]:http://thread.gmane.org/gmane.linux.kernel.iommu/11974
drivers/iommu/io-pgtable-arm-v7s.c | 5 +
drivers/iommu/io-pgtable-arm.c | 13 +++--
drivers/iommu/io-pgtable.h | 22 ++
3 files changed, 34 insertions(+), 6 deletions(-)
diff --git a/drivers/iommu/io-pgtable-arm-v7s.c
b/drivers/iommu/io-pgtable-arm-v7s.c
index d39a021..9fcceb1 100644
--- a/drivers/iommu/io-pgtable-arm-v7s.c
+++ b/drivers/iommu/io-pgtable-arm-v7s.c
@@ -623,6 +623,11 @@ static struct io_pgtable *arm_v7s_alloc_pgtable(struct
io_pgtable_cfg *cfg,
if (cfg->ias > ARM_V7S_ADDR_BITS || cfg->oas > ARM_V7S_ADDR_BITS)
return NULL;
+ if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
+ IO_PGTABLE_QUIRK_NO_PERMS |
+ IO_PGTABLE_QUIRK_TLBI_ON_MAP))
+ return NULL;
+
data = kmalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return NULL;
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 4095af2..debdf04 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -658,8 +658,12 @@ static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
{
u64 reg;
- struct arm_lpae_io_pgtable *data = arm_lpae_alloc_pgtable(cfg);
+ struct arm_lpae_io_pgtable *data;
+ if (cfg->quirks & ~IO_PGTABLE_QUIRK_ARM_NS)
+ return NULL;
+
+ data = arm_lpae_alloc_pgtable(cfg);
if (!data)
return NULL;
@@ -742,8 +746,13 @@ static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
{
u64 reg, sl;
- struct arm_lpae_io_pgtable *data = arm_lpae_alloc_pgtable(cfg);
+ struct arm_lpae_io_pgtable *data;
+ /* The NS quirk doesn't apply at stage 2 */
+ if (cfg->quirks)
+ return NULL;
+
+ data = arm_lpae_alloc_pgtable(cfg);
if (!data)
return NULL;
diff --git a/drivers/iommu/io-pgtable.h b/drivers/iommu/io-pgtable.h
index 4faee7d..d4f5027 100644
--- a/drivers/iommu/io-pgtable.h
+++ b/drivers/iommu/io-pgtable.h
@@ -47,10 +47,24 @@ struct iommu_gather_ops {
* page table walker.
*/
struct io_pgtable_cfg {
- #define IO_PGTABLE_QUIRK_ARM_NS BIT(0) /* Set NS bit in PTEs */
- #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1) /* No AP/XN bits */
- #define IO_PGTABLE_QUIRK_TLBI_ON_MAPBIT(2) /* TLB Inv. on map */
- int quirks;
+ /*
+* IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
+* stage 1 PTEs, for hardware which insists on validating them
+* even in non-secure state where they should normally be ignored.
+*
+* IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
+* IOMMU_NOEXEC flags and map everything with full access, for
+* hardware which does not implement the permissions of a given
+* format, and/or requires some format-specific default value.
+*
+* IO_PGTABLE_QUIRK_TLBI_ON_MAP: If the format forbids caching invalid
+* (unmapped) entries but the hardware might do so anyway, perform
+* TLB maintenance when mapping as well as when unmapping.
+*/
+ #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
+ #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
+ #define IO_PGTABLE_QUIRK_TLBI_ON_MAPBIT(2)
+ unsigned long quirks;
unsigned long pgsize_bitmap;
unsigned intias;
unsigned intoas;
--
2.7.0.25.gfc10eb5.dirty
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