Commit 4c0fa5bf authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: debugfs: Add support to show inv queue internals 



Export invalidation queue internals of each iommu device through the
debugfs.

Example of such dump on a Skylake machine:

$ sudo cat /sys/kernel/debug/iommu/intel/invalidation_queue
Invalidation queue on IOMMU: dmar1
 Base: 0x1672c9000      Head: 80        Tail: 80
Index           qw0                     qw1                     status
    0   0000000000000004        0000000000000000        0000000000000000
    1   0000000200000025        00000001672be804        0000000000000000
    2   0000000000000011        0000000000000000        0000000000000000
    3   0000000200000025        00000001672be80c        0000000000000000
    4   00000000000000d2        0000000000000000        0000000000000000
    5   0000000200000025        00000001672be814        0000000000000000
    6   0000000000000014        0000000000000000        0000000000000000
    7   0000000200000025        00000001672be81c        0000000000000000
    8   0000000000000014        0000000000000000        0000000000000000
    9   0000000200000025        00000001672be824        0000000000000000

Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20200516062101.29541-14-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 8a1d8246

drivers/iommu/intel-iommu-debugfs.c

+62 −0
Original line number Diff line number Diff line
@@ -372,6 +372,66 @@ static int domain_translation_struct_show(struct seq_file *m, void *unused) 
}

DEFINE_SHOW_ATTRIBUTE(domain_translation_struct);



static void invalidation_queue_entry_show(struct seq_file *m,

					  struct intel_iommu *iommu)

{

	int index, shift = qi_shift(iommu);

	struct qi_desc *desc;

	int offset;



	if (ecap_smts(iommu->ecap))

		seq_puts(m, "Index\t\tqw0\t\t\tqw1\t\t\tqw2\t\t\tqw3\t\t\tstatus\n");

	else

		seq_puts(m, "Index\t\tqw0\t\t\tqw1\t\t\tstatus\n");



	for (index = 0; index < QI_LENGTH; index++) {

		offset = index << shift;

		desc = iommu->qi->desc + offset;

		if (ecap_smts(iommu->ecap))

			seq_printf(m, "%5d\t%016llx\t%016llx\t%016llx\t%016llx\t%016x\n",

				   index, desc->qw0, desc->qw1,

				   desc->qw2, desc->qw3,

				   iommu->qi->desc_status[index]);

		else

			seq_printf(m, "%5d\t%016llx\t%016llx\t%016x\n",

				   index, desc->qw0, desc->qw1,

				   iommu->qi->desc_status[index]);

	}

}



static int invalidation_queue_show(struct seq_file *m, void *unused)

{

	struct dmar_drhd_unit *drhd;

	struct intel_iommu *iommu;

	unsigned long flags;

	struct q_inval *qi;

	int shift;



	rcu_read_lock();

	for_each_active_iommu(iommu, drhd) {

		qi = iommu->qi;

		shift = qi_shift(iommu);



		if (!qi || !ecap_qis(iommu->ecap))

			continue;



		seq_printf(m, "Invalidation queue on IOMMU: %s\n", iommu->name);



		raw_spin_lock_irqsave(&qi->q_lock, flags);

		seq_printf(m, " Base: 0x%llx\tHead: %lld\tTail: %lld\n",

			   (u64)virt_to_phys(qi->desc),

			   dmar_readq(iommu->reg + DMAR_IQH_REG) >> shift,

			   dmar_readq(iommu->reg + DMAR_IQT_REG) >> shift);

		invalidation_queue_entry_show(m, iommu);

		raw_spin_unlock_irqrestore(&qi->q_lock, flags);

		seq_putc(m, '\n');

	}

	rcu_read_unlock();



	return 0;

}

DEFINE_SHOW_ATTRIBUTE(invalidation_queue);



#ifdef CONFIG_IRQ_REMAP

static void ir_tbl_remap_entry_show(struct seq_file *m,

				    struct intel_iommu *iommu)
@@ -490,6 +550,8 @@ void __init intel_iommu_debugfs_init(void) 
	debugfs_create_file("domain_translation_struct", 0444,

			    intel_iommu_debug, NULL,

			    &domain_translation_struct_fops);

	debugfs_create_file("invalidation_queue", 0444, intel_iommu_debug,

			    NULL, &invalidation_queue_fops);

#ifdef CONFIG_IRQ_REMAP

	debugfs_create_file("ir_translation_struct", 0444, intel_iommu_debug,

			    NULL, &ir_translation_struct_fops);

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