Commit f9a38ea5 authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

x86: always initialize xen-swiotlb when xen-pcifront is enabling 



Remove the dangerous late initialization of xen-swiotlb in
pci_xen_swiotlb_init_late and instead just always initialize
xen-swiotlb in the boot code if CONFIG_XEN_PCIDEV_FRONTEND is
enabled and Xen PV PCI is possible.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
parent 358cd9af

arch/x86/include/asm/xen/swiotlb-xen.h

+0 −6
Original line number Diff line number Diff line
@@ -2,12 +2,6 @@ 
#ifndef _ASM_X86_SWIOTLB_XEN_H

#define _ASM_X86_SWIOTLB_XEN_H



#ifdef CONFIG_SWIOTLB_XEN

extern int pci_xen_swiotlb_init_late(void);

#else

static inline int pci_xen_swiotlb_init_late(void) { return -ENXIO; }

#endif



int xen_swiotlb_fixup(void *buf, unsigned long nslabs);

int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order,

				unsigned int address_bits,

arch/x86/kernel/pci-dma.c

+7 −22
Original line number Diff line number Diff line
@@ -72,9 +72,15 @@ static inline void __init pci_swiotlb_detect(void) 
#endif /* CONFIG_SWIOTLB */



#ifdef CONFIG_SWIOTLB_XEN

static bool xen_swiotlb_enabled(void)

{

	return xen_initial_domain() || x86_swiotlb_enable ||

		(IS_ENABLED(CONFIG_XEN_PCIDEV_FRONTEND) && xen_pv_pci_possible);

}



static void __init pci_xen_swiotlb_init(void)

{

	if (!xen_initial_domain() && !x86_swiotlb_enable)

	if (!xen_swiotlb_enabled())

		return;

	x86_swiotlb_enable = true;

	x86_swiotlb_flags |= SWIOTLB_ANY;
@@ -83,27 +89,6 @@ static void __init pci_xen_swiotlb_init(void) 
	if (IS_ENABLED(CONFIG_PCI))

		pci_request_acs();

}



int pci_xen_swiotlb_init_late(void)

{

	if (dma_ops == &xen_swiotlb_dma_ops)

		return 0;



	/* we can work with the default swiotlb */

	if (!io_tlb_default_mem.nslabs) {

		int rc = swiotlb_init_late(swiotlb_size_or_default(),

					   GFP_KERNEL, xen_swiotlb_fixup);

		if (rc < 0)

			return rc;

	}



	/* XXX: this switches the dma ops under live devices! */

	dma_ops = &xen_swiotlb_dma_ops;

	if (IS_ENABLED(CONFIG_PCI))

		pci_request_acs();

	return 0;

}

EXPORT_SYMBOL_GPL(pci_xen_swiotlb_init_late);

#else

static inline void __init pci_xen_swiotlb_init(void)

{

drivers/pci/xen-pcifront.c

+0 −6
Original line number Diff line number Diff line
@@ -22,7 +22,6 @@ 
#include <linux/bitops.h>

#include <linux/time.h>

#include <linux/ktime.h>

#include <linux/swiotlb.h>

#include <xen/platform_pci.h>



#include <asm/xen/swiotlb-xen.h>
@@ -669,11 +668,6 @@ static int pcifront_connect_and_init_dma(struct pcifront_device *pdev) 


	spin_unlock(&pcifront_dev_lock);



	if (!err && !is_swiotlb_active(&pdev->xdev->dev)) {

		err = pci_xen_swiotlb_init_late();

		if (err)

			dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n");

	}

	return err;

}