* [PATCH 1/2] iommu/amd: Add align parameter to alloc_irq_index()
2017-10-06 11:34 [PATCH 0/2] iommu/amd: Correctly Align Multiple MSI IRQs Joerg Roedel
@ 2017-10-06 11:34 ` Joerg Roedel
2017-10-08 8:39 ` Thomas Gleixner
2017-10-06 11:34 ` [PATCH 2/2] iommu/amd: Enforce alignment for MSI IRQs Joerg Roedel
1 sibling, 1 reply; 5+ messages in thread
From: Joerg Roedel @ 2017-10-06 11:34 UTC (permalink / raw)
To: iommu; +Cc: Thomas Gleixner, linux-kernel, Joerg Roedel
From: Joerg Roedel <jroedel@suse.de>
For multi-MSI IRQ ranges the IRQ index needs to be aligned
to the power-of-two of the requested IRQ count. Extend the
alloc_irq_index() function to allow such an allocation.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Fixes: 2b324506341cb ('iommu/amd: Add routines to manage irq remapping tables')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/amd_iommu.c | 22 ++++++++++++++--------
1 file changed, 14 insertions(+), 8 deletions(-)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 51f8215..2d4ee25 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3660,11 +3660,11 @@ static struct irq_remap_table *get_irq_table(u16 devid, bool ioapic)
return table;
}
-static int alloc_irq_index(u16 devid, int count)
+static int alloc_irq_index(u16 devid, int count, bool align)
{
struct irq_remap_table *table;
+ int index, c, alignment = 1;
unsigned long flags;
- int index, c;
struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
if (!iommu)
@@ -3674,16 +3674,22 @@ static int alloc_irq_index(u16 devid, int count)
if (!table)
return -ENODEV;
+ if (align)
+ alignment = roundup_pow_of_two(count);
+
spin_lock_irqsave(&table->lock, flags);
/* Scan table for free entries */
- for (c = 0, index = table->min_index;
+ for (index = ALIGN(table->min_index, alignment), c = 0;
index < MAX_IRQS_PER_TABLE;
- ++index) {
- if (!iommu->irte_ops->is_allocated(table, index))
+ index++) {
+ if (!iommu->irte_ops->is_allocated(table, index)) {
c += 1;
- else
- c = 0;
+ } else {
+ c = 0;
+ index = ALIGN(index, alignment);
+ continue;
+ }
if (c == count) {
for (; c != 0; --c)
@@ -4096,7 +4102,7 @@ static int irq_remapping_alloc(struct irq_domain *domain, unsigned int virq,
else
ret = -ENOMEM;
} else {
- index = alloc_irq_index(devid, nr_irqs);
+ index = alloc_irq_index(devid, nr_irqs, false);
}
if (index < 0) {
pr_warn("Failed to allocate IRTE\n");
--
2.7.4
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH 2/2] iommu/amd: Enforce alignment for MSI IRQs
2017-10-06 11:34 [PATCH 0/2] iommu/amd: Correctly Align Multiple MSI IRQs Joerg Roedel
2017-10-06 11:34 ` [PATCH 1/2] iommu/amd: Add align parameter to alloc_irq_index() Joerg Roedel
@ 2017-10-06 11:34 ` Joerg Roedel
2017-10-08 8:40 ` Thomas Gleixner
1 sibling, 1 reply; 5+ messages in thread
From: Joerg Roedel @ 2017-10-06 11:34 UTC (permalink / raw)
To: iommu; +Cc: Thomas Gleixner, linux-kernel, Joerg Roedel
From: Joerg Roedel <jroedel@suse.de>
Make use of the new alignment capability of
alloc_irq_index() to enforce IRQ index alignment
for MSI.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Fixes: 2b324506341cb ('iommu/amd: Add routines to manage irq remapping tables')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/amd_iommu.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 2d4ee25..cb7c531 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -4102,7 +4102,9 @@ static int irq_remapping_alloc(struct irq_domain *domain, unsigned int virq,
else
ret = -ENOMEM;
} else {
- index = alloc_irq_index(devid, nr_irqs, false);
+ bool align = (info->type == X86_IRQ_ALLOC_TYPE_MSI);
+
+ index = alloc_irq_index(devid, nr_irqs, align);
}
if (index < 0) {
pr_warn("Failed to allocate IRTE\n");
--
2.7.4
^ permalink raw reply [flat|nested] 5+ messages in thread