From: Nadav Amit <[email protected]>
The previous patch, commit 268aa4548277 ("iommu/amd: Page-specific
invalidations for more than one page") was supposed to enable
page-selective IOTLB flushes on AMD.
The patch had an embaressing bug, and I apologize for it.
Analysis as for why this bug did not result in failures raised
additional issues that caused at least most of the IOTLB flushes not to
be page-selective ones.
The first patch corrects the bug from the previous patch. The next
patches enable page-selective invalidations, which were not enabled
despite the previous patch.
Cc: Joerg Roedel <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Jiajun Cao <[email protected]>
Cc: [email protected]
Cc: [email protected]
Nadav Amit (4):
iommu/amd: Fix wrong parentheses on page-specific invalidations
iommu/amd: Selective flush on unmap
iommu/amd: Do not sync on page size changes
iommu/amd: Do not use flush-queue when NpCache is on
drivers/iommu/amd/init.c | 7 ++++++-
drivers/iommu/amd/iommu.c | 18 +++++++++++++++---
include/linux/iommu.h | 3 ++-
3 files changed, 23 insertions(+), 5 deletions(-)
--
2.25.1
From: Nadav Amit <[email protected]>
Some IOMMU architectures perform invalidations regardless of the page
size. In such architectures there is no need to sync when the page size
changes. In such architecture, there is no need to regard pgsize when
making interim flush in iommu_iotlb_gather_add_page().
Add a "no_sync_on_pgsize_change" property for each IOMMU ops to decide
whether gather's pgsize is tracked and triggers a flush.
Cc: Joerg Roedel <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Jiajun Cao <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Nadav Amit <[email protected]>
---
drivers/iommu/amd/iommu.c | 1 +
include/linux/iommu.h | 3 ++-
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 6723cbcf4030..8a71ad477c34 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2204,6 +2204,7 @@ const struct iommu_ops amd_iommu_ops = {
.put_resv_regions = generic_iommu_put_resv_regions,
.is_attach_deferred = amd_iommu_is_attach_deferred,
.pgsize_bitmap = AMD_IOMMU_PGSIZES,
+ .ignore_gather_pgsize = true,
.flush_iotlb_all = amd_iommu_flush_iotlb_all,
.iotlb_sync = amd_iommu_iotlb_sync,
.def_domain_type = amd_iommu_def_domain_type,
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 32d448050bf7..1fb2695418e9 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -284,6 +284,7 @@ struct iommu_ops {
int (*def_domain_type)(struct device *dev);
unsigned long pgsize_bitmap;
+ bool ignore_gather_pgsize;
struct module *owner;
};
@@ -508,7 +509,7 @@ static inline void iommu_iotlb_gather_add_page(struct iommu_domain *domain,
* a different granularity, then sync the TLB so that the gather
* structure can be rewritten.
*/
- if (gather->pgsize != size ||
+ if ((gather->pgsize != size && !domain->ops->ignore_gather_pgsize) ||
end + 1 < gather->start || start > gather->end + 1) {
if (gather->pgsize)
iommu_iotlb_sync(domain, gather);
--
2.25.1
From: Nadav Amit <[email protected]>
Recent patch attempted to enable selective page flushes on AMD IOMMU but
neglected to adapt amd_iommu_iotlb_sync() to use the selective flushes.
Adapt amd_iommu_iotlb_sync() to use selective flushes and change
amd_iommu_unmap() to collect the flushes. As a defensive measure, to
avoid potential issues as those that the Intel IOMMU driver encountered
recently, flush the page-walk caches by always setting the "pde"
parameter. This can be removed later.
Cc: Joerg Roedel <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Jiajun Cao <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Nadav Amit <[email protected]>
---
drivers/iommu/amd/iommu.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 6723cbcf4030..b8cabbbeed71 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2057,12 +2057,17 @@ static size_t amd_iommu_unmap(struct iommu_domain *dom, unsigned long iova,
{
struct protection_domain *domain = to_pdomain(dom);
struct io_pgtable_ops *ops = &domain->iop.iop.ops;
+ size_t r;
if ((amd_iommu_pgtable == AMD_IOMMU_V1) &&
(domain->iop.mode == PAGE_MODE_NONE))
return 0;
- return (ops->unmap) ? ops->unmap(ops, iova, page_size, gather) : 0;
+ r = (ops->unmap) ? ops->unmap(ops, iova, page_size, gather) : 0;
+
+ iommu_iotlb_gather_add_page(dom, gather, iova, page_size);
+
+ return r;
}
static phys_addr_t amd_iommu_iova_to_phys(struct iommu_domain *dom,
@@ -2165,7 +2170,13 @@ static void amd_iommu_flush_iotlb_all(struct iommu_domain *domain)
static void amd_iommu_iotlb_sync(struct iommu_domain *domain,
struct iommu_iotlb_gather *gather)
{
- amd_iommu_flush_iotlb_all(domain);
+ struct protection_domain *dom = to_pdomain(domain);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dom->lock, flags);
+ __domain_flush_pages(dom, gather->start, gather->end - gather->start, 1);
+ amd_iommu_domain_flush_complete(dom);
+ spin_unlock_irqrestore(&dom->lock, flags);
}
static int amd_iommu_def_domain_type(struct device *dev)
--
2.25.1
From: Nadav Amit <[email protected]>
Some IOMMU architectures perform invalidations regardless of the page
size. In such architectures there is no need to sync when the page size
changes or to regard pgsize when making interim flush in
iommu_iotlb_gather_add_page().
Add a "ignore_gather_pgsize" property for each IOMMU-ops to decide
whether gather's pgsize is tracked and triggers a flush.
Cc: Joerg Roedel <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Jiajun Cao <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Nadav Amit <[email protected]>
---
drivers/iommu/amd/iommu.c | 1 +
include/linux/iommu.h | 3 ++-
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index b8cabbbeed71..1849b53f2149 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2215,6 +2215,7 @@ const struct iommu_ops amd_iommu_ops = {
.put_resv_regions = generic_iommu_put_resv_regions,
.is_attach_deferred = amd_iommu_is_attach_deferred,
.pgsize_bitmap = AMD_IOMMU_PGSIZES,
+ .ignore_gather_pgsize = true,
.flush_iotlb_all = amd_iommu_flush_iotlb_all,
.iotlb_sync = amd_iommu_iotlb_sync,
.def_domain_type = amd_iommu_def_domain_type,
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 32d448050bf7..1fb2695418e9 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -284,6 +284,7 @@ struct iommu_ops {
int (*def_domain_type)(struct device *dev);
unsigned long pgsize_bitmap;
+ bool ignore_gather_pgsize;
struct module *owner;
};
@@ -508,7 +509,7 @@ static inline void iommu_iotlb_gather_add_page(struct iommu_domain *domain,
* a different granularity, then sync the TLB so that the gather
* structure can be rewritten.
*/
- if (gather->pgsize != size ||
+ if ((gather->pgsize != size && !domain->ops->ignore_gather_pgsize) ||
end + 1 < gather->start || start > gather->end + 1) {
if (gather->pgsize)
iommu_iotlb_sync(domain, gather);
--
2.25.1
From: Nadav Amit <[email protected]>
Recent patch attempted to enable selective page flushes on AMD IOMMU but
neglected to adapt amd_iommu_iotlb_sync() to use the selective flushes.
Adapt amd_iommu_iotlb_sync() to use selective flushes and change
amd_iommu_unmap() to collect the flushes. As a defensive measure, to
avoid potential issues as those that the Intel IOMMU driver encountered
recently, flush the page-walk caches by always setting the "pde"
parameter. This can be removed later.
Cc: Joerg Roedel <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Jiajun Cao <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Nadav Amit <[email protected]>
---
drivers/iommu/amd/iommu.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 8a71ad477c34..1849b53f2149 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2057,12 +2057,17 @@ static size_t amd_iommu_unmap(struct iommu_domain *dom, unsigned long iova,
{
struct protection_domain *domain = to_pdomain(dom);
struct io_pgtable_ops *ops = &domain->iop.iop.ops;
+ size_t r;
if ((amd_iommu_pgtable == AMD_IOMMU_V1) &&
(domain->iop.mode == PAGE_MODE_NONE))
return 0;
- return (ops->unmap) ? ops->unmap(ops, iova, page_size, gather) : 0;
+ r = (ops->unmap) ? ops->unmap(ops, iova, page_size, gather) : 0;
+
+ iommu_iotlb_gather_add_page(dom, gather, iova, page_size);
+
+ return r;
}
static phys_addr_t amd_iommu_iova_to_phys(struct iommu_domain *dom,
@@ -2165,7 +2170,13 @@ static void amd_iommu_flush_iotlb_all(struct iommu_domain *domain)
static void amd_iommu_iotlb_sync(struct iommu_domain *domain,
struct iommu_iotlb_gather *gather)
{
- amd_iommu_flush_iotlb_all(domain);
+ struct protection_domain *dom = to_pdomain(domain);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dom->lock, flags);
+ __domain_flush_pages(dom, gather->start, gather->end - gather->start, 1);
+ amd_iommu_domain_flush_complete(dom);
+ spin_unlock_irqrestore(&dom->lock, flags);
}
static int amd_iommu_def_domain_type(struct device *dev)
--
2.25.1
From: Nadav Amit <[email protected]>
Do not use flush-queue on virtualized environments, where the NpCache
capability of the IOMMU is set. This is required to reduce
virtualization overheads.
This change follows a similar change to Intel's VT-d and a detailed
explanation as for the rationale is described in commit 29b32839725f
("iommu/vt-d: Do not use flush-queue when caching-mode is on").
Cc: Joerg Roedel <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Jiajun Cao <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Nadav Amit <[email protected]>
---
drivers/iommu/amd/init.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index d006724f4dc2..ba3b76ed776d 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -1850,8 +1850,13 @@ static int __init iommu_init_pci(struct amd_iommu *iommu)
if (ret)
return ret;
- if (iommu->cap & (1UL << IOMMU_CAP_NPCACHE))
+ if (iommu->cap & (1UL << IOMMU_CAP_NPCACHE)) {
+ if (!amd_iommu_unmap_flush)
+ pr_warn_once("IOMMU batching is disabled due to virtualization");
+
amd_iommu_np_cache = true;
+ amd_iommu_unmap_flush = true;
+ }
init_iommu_perf_ctr(iommu);
--
2.25.1
On 2021-05-02 07:59, Nadav Amit wrote:
> From: Nadav Amit <[email protected]>
>
> Some IOMMU architectures perform invalidations regardless of the page
> size. In such architectures there is no need to sync when the page size
> changes or to regard pgsize when making interim flush in
> iommu_iotlb_gather_add_page().
>
> Add a "ignore_gather_pgsize" property for each IOMMU-ops to decide
> whether gather's pgsize is tracked and triggers a flush.
I've objected before[1], and I'll readily object again ;)
I still think it's very silly to add a bunch of indirection all over the
place to make a helper function not do the main thing it's intended to
help with. If you only need trivial address gathering then it's far
simpler to just implement trivial address gathering. I suppose if you
really want to you could factor out another helper to share the 5 lines
of code which ended up in mtk-iommu (see commit f21ae3b10084).
Robin.
[1]
https://lore.kernel.org/linux-iommu/[email protected]/
> Cc: Joerg Roedel <[email protected]>
> Cc: Will Deacon <[email protected]>
> Cc: Jiajun Cao <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Nadav Amit <[email protected]>
> ---
> drivers/iommu/amd/iommu.c | 1 +
> include/linux/iommu.h | 3 ++-
> 2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index b8cabbbeed71..1849b53f2149 100644
> --- a/drivers/iommu/amd/iommu.c
> +++ b/drivers/iommu/amd/iommu.c
> @@ -2215,6 +2215,7 @@ const struct iommu_ops amd_iommu_ops = {
> .put_resv_regions = generic_iommu_put_resv_regions,
> .is_attach_deferred = amd_iommu_is_attach_deferred,
> .pgsize_bitmap = AMD_IOMMU_PGSIZES,
> + .ignore_gather_pgsize = true,
> .flush_iotlb_all = amd_iommu_flush_iotlb_all,
> .iotlb_sync = amd_iommu_iotlb_sync,
> .def_domain_type = amd_iommu_def_domain_type,
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index 32d448050bf7..1fb2695418e9 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -284,6 +284,7 @@ struct iommu_ops {
> int (*def_domain_type)(struct device *dev);
>
> unsigned long pgsize_bitmap;
> + bool ignore_gather_pgsize;
> struct module *owner;
> };
>
> @@ -508,7 +509,7 @@ static inline void iommu_iotlb_gather_add_page(struct iommu_domain *domain,
> * a different granularity, then sync the TLB so that the gather
> * structure can be rewritten.
> */
> - if (gather->pgsize != size ||
> + if ((gather->pgsize != size && !domain->ops->ignore_gather_pgsize) ||
> end + 1 < gather->start || start > gather->end + 1) {
> if (gather->pgsize)
> iommu_iotlb_sync(domain, gather);
>
> On Jun 1, 2021, at 8:59 AM, Robin Murphy <[email protected]> wrote:
>
> On 2021-05-02 07:59, Nadav Amit wrote:
>> From: Nadav Amit <[email protected]>
>> Some IOMMU architectures perform invalidations regardless of the page
>> size. In such architectures there is no need to sync when the page size
>> changes or to regard pgsize when making interim flush in
>> iommu_iotlb_gather_add_page().
>> Add a "ignore_gather_pgsize" property for each IOMMU-ops to decide
>> whether gather's pgsize is tracked and triggers a flush.
>
> I've objected before[1], and I'll readily object again ;)
>
> I still think it's very silly to add a bunch of indirection all over the place to make a helper function not do the main thing it's intended to help with. If you only need trivial address gathering then it's far simpler to just implement trivial address gathering. I suppose if you really want to you could factor out another helper to share the 5 lines of code which ended up in mtk-iommu (see commit f21ae3b10084).
Thanks, Robin.
I read your comments but I cannot fully understand the alternative that you propose, although I do understand your objection to the indirection “ignore_gather_pgsize”. Would it be ok if “ignore_gather_pgsize" was provided as an argument for iommu_iotlb_gather_add_page()?
In general, I can live without this patch. It probably would have negligent impact on performance anyhow.
Regards,
Nadav
On 2021-06-01 17:39, Nadav Amit wrote:
>
>
>> On Jun 1, 2021, at 8:59 AM, Robin Murphy <[email protected]> wrote:
>>
>> On 2021-05-02 07:59, Nadav Amit wrote:
>>> From: Nadav Amit <[email protected]>
>>> Some IOMMU architectures perform invalidations regardless of the page
>>> size. In such architectures there is no need to sync when the page size
>>> changes or to regard pgsize when making interim flush in
>>> iommu_iotlb_gather_add_page().
>>> Add a "ignore_gather_pgsize" property for each IOMMU-ops to decide
>>> whether gather's pgsize is tracked and triggers a flush.
>>
>> I've objected before[1], and I'll readily object again ;)
>>
>> I still think it's very silly to add a bunch of indirection all over the place to make a helper function not do the main thing it's intended to help with. If you only need trivial address gathering then it's far simpler to just implement trivial address gathering. I suppose if you really want to you could factor out another helper to share the 5 lines of code which ended up in mtk-iommu (see commit f21ae3b10084).
>
> Thanks, Robin.
>
> I read your comments but I cannot fully understand the alternative that you propose, although I do understand your objection to the indirection “ignore_gather_pgsize”. Would it be ok if “ignore_gather_pgsize" was provided as an argument for iommu_iotlb_gather_add_page()?
No, I mean if iommu_iotlb_gather_add_page() doesn't have the behaviour
your driver wants, just don't call it. Write or factor out a suitable
helper that *does* do what you want and call that, or just implement the
logic directly inline. Indirect argument or not, it just doesn't make
much sense to have a helper function call which says "do this except
don't do most of it".
> In general, I can live without this patch. It probably would have negligent impact on performance anyhow.
As I implied, it sounds like your needs are the same as the Mediatek
driver had, so you could readily factor out a new page-size-agnostic
gather helper from that. I fully support making the functional change to
amd-iommu *somehow* - nobody likes unnecessary syncs - just not with
this particular implementation :)
Robin.
> On Jun 1, 2021, at 10:27 AM, Robin Murphy <[email protected]> wrote:
>
> On 2021-06-01 17:39, Nadav Amit wrote:
>>> On Jun 1, 2021, at 8:59 AM, Robin Murphy <[email protected]> wrote:
>>>
>>> On 2021-05-02 07:59, Nadav Amit wrote:
>>>> From: Nadav Amit <[email protected]>
>>>> Some IOMMU architectures perform invalidations regardless of the page
>>>> size. In such architectures there is no need to sync when the page size
>>>> changes or to regard pgsize when making interim flush in
>>>> iommu_iotlb_gather_add_page().
>>>> Add a "ignore_gather_pgsize" property for each IOMMU-ops to decide
>>>> whether gather's pgsize is tracked and triggers a flush.
>>>
>>> I've objected before[1], and I'll readily object again ;)
>>>
>>> I still think it's very silly to add a bunch of indirection all over the place to make a helper function not do the main thing it's intended to help with. If you only need trivial address gathering then it's far simpler to just implement trivial address gathering. I suppose if you really want to you could factor out another helper to share the 5 lines of code which ended up in mtk-iommu (see commit f21ae3b10084).
>> Thanks, Robin.
>> I read your comments but I cannot fully understand the alternative that you propose, although I do understand your objection to the indirection “ignore_gather_pgsize”. Would it be ok if “ignore_gather_pgsize" was provided as an argument for iommu_iotlb_gather_add_page()?
>
> No, I mean if iommu_iotlb_gather_add_page() doesn't have the behaviour your driver wants, just don't call it. Write or factor out a suitable helper that *does* do what you want and call that, or just implement the logic directly inline. Indirect argument or not, it just doesn't make much sense to have a helper function call which says "do this except don't do most of it".
>
>> In general, I can live without this patch. It probably would have negligent impact on performance anyhow.
>
> As I implied, it sounds like your needs are the same as the Mediatek driver had, so you could readily factor out a new page-size-agnostic gather helper from that. I fully support making the functional change to amd-iommu *somehow* - nobody likes unnecessary syncs - just not with this particular implementation :)
Hm… avoid code duplication I need to extract some common code to another function.
Is the following resembles what you had in mind (untested)?
-- >8 --
Subject: [PATCH] iommu: add iommu_iotlb_gather_add_page_ignore_pgsize()
---
drivers/iommu/mtk_iommu.c | 7 ++---
include/linux/iommu.h | 55 ++++++++++++++++++++++++++++++---------
2 files changed, 44 insertions(+), 18 deletions(-)
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index e168a682806a..5890e745bed3 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -520,12 +520,9 @@ static size_t mtk_iommu_unmap(struct iommu_domain *domain,
struct iommu_iotlb_gather *gather)
{
struct mtk_iommu_domain *dom = to_mtk_domain(domain);
- unsigned long end = iova + size - 1;
- if (gather->start > iova)
- gather->start = iova;
- if (gather->end < end)
- gather->end = end;
+ iommu_iotlb_gather_update_range(gather, iova, size);
+
return dom->iop->unmap(dom->iop, iova, size, gather);
}
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 9ca6e6b8084d..037434b6eb4c 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -535,29 +535,58 @@ static inline void iommu_iotlb_sync(struct iommu_domain *domain,
iommu_iotlb_gather_init(iotlb_gather);
}
-static inline void iommu_iotlb_gather_add_page(struct iommu_domain *domain,
+static inline
+void iommu_iotlb_gather_update_range(struct iommu_iotlb_gather *gather,
+ unsigned long iova, size_t size)
+{
+ unsigned long start = iova, end = start + size - 1;
+
+ if (gather->end < end)
+ gather->end = end;
+
+ if (gather->start > start)
+ gather->start = start;
+
+ gather->pgsize = size;
+}
+
+static inline
+bool iommu_iotlb_gather_is_disjoint(struct iommu_iotlb_gather *gather,
+ unsigned long iova, size_t size)
+{
+ return iova + size < gather->start || iova > gather->end + 1;
+}
+
+static inline
+void iommu_iotlb_gather_add_page_ignore_pgsize(struct iommu_domain *domain,
struct iommu_iotlb_gather *gather,
unsigned long iova, size_t size)
{
- unsigned long start = iova, end = start + size - 1;
+ /*
+ * Only if the new page is disjoint from the current range, then sync
+ * the TLB so that the gather structure can be rewritten.
+ */
+ if (iommu_iotlb_gather_is_disjoint(gather, iova, size) && gather->pgsize)
+ iommu_iotlb_sync(domain, gather);
+
+ iommu_iotlb_gather_update_range(gather, iova, size);
+}
+static inline void iommu_iotlb_gather_add_page(struct iommu_domain *domain,
+ struct iommu_iotlb_gather *gather,
+ unsigned long iova, size_t size)
+{
/*
* If the new page is disjoint from the current range or is mapped at
* a different granularity, then sync the TLB so that the gather
* structure can be rewritten.
*/
- if (gather->pgsize != size ||
- end + 1 < gather->start || start > gather->end + 1) {
- if (gather->pgsize)
- iommu_iotlb_sync(domain, gather);
- gather->pgsize = size;
- }
-
- if (gather->end < end)
- gather->end = end;
+ if ((gather->pgsize != size ||
+ iommu_iotlb_gather_is_disjoint(gather, iova, size)) &&
+ gather->pgsize)
+ iommu_iotlb_sync(domain, gather);
- if (gather->start > start)
- gather->start = start;
+ iommu_iotlb_gather_update_range(gather, iova, size);
}
/* PCI device grouping function */
--
2.25.1