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Commit 355bf553 authored by Joerg Roedel's avatar Joerg Roedel
Browse files

AMD IOMMU: add device detach helper functions 



Impact: add helper functions to detach a device from a domain

Signed-off-by: default avatarJoerg Roedel <joerg.roedel@amd.com>
parent f1179dc0

arch/x86/kernel/amd_iommu.c

+39 −0
Original line number Original line Diff line number Diff line
@@ -844,6 +844,45 @@ static void attach_device(struct amd_iommu *iommu, 
	iommu_queue_inv_dev_entry(iommu, devid);

	iommu_queue_inv_dev_entry(iommu, devid);

}

}





#ifdef CONFIG_IOMMU_API

/*

 * Removes a device from a protection domain (unlocked)

 */

static void __detach_device(struct protection_domain *domain, u16 devid)

{



	/* lock domain */

	spin_lock(&domain->lock);



	/* remove domain from the lookup table */

	amd_iommu_pd_table[devid] = NULL;



	/* remove entry from the device table seen by the hardware */

	amd_iommu_dev_table[devid].data[0] = IOMMU_PTE_P | IOMMU_PTE_TV;

	amd_iommu_dev_table[devid].data[1] = 0;

	amd_iommu_dev_table[devid].data[2] = 0;



	/* decrease reference counter */

	domain->dev_cnt -= 1;



	/* ready */

	spin_unlock(&domain->lock);

}



/*

 * Removes a device from a protection domain (with devtable_lock held)

 */

static void detach_device(struct protection_domain *domain, u16 devid)

{

	unsigned long flags;



	/* lock device table */

	write_lock_irqsave(&amd_iommu_devtable_lock, flags);

	__detach_device(domain, devid);

	write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);

}

#endif



/*****************************************************************************

/*****************************************************************************

 *

 *

 * The next functions belong to the dma_ops mapping/unmapping code.

 * The next functions belong to the dma_ops mapping/unmapping code.