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author | 2017-10-06 12:16:39 +0200 | |
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committer | 2017-10-10 16:03:43 +0200 | |
commit | 37946d95fc1a41ed79efb613b0818c2cdecbb2fa (patch) | |
tree | b03dc00f35958ffe8e76fe2071b64b57c4ff2e8f /drivers/iommu | |
parent | Linux 4.14-rc3 (diff) | |
download | linux-37946d95fc1a41ed79efb613b0818c2cdecbb2fa.tar.gz linux-37946d95fc1a41ed79efb613b0818c2cdecbb2fa.tar.bz2 linux-37946d95fc1a41ed79efb613b0818c2cdecbb2fa.zip |
iommu/amd: Add align parameter to alloc_irq_index()
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')
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu')
-rw-r--r-- | drivers/iommu/amd_iommu.c | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 51f8215877f5..2d4ee2555a0d 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -3660,11 +3660,11 @@ out_unlock: 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"); |