Commit 78013eaa authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

x86: remove the IOMMU table infrastructure 



The IOMMU table tries to separate the different IOMMUs into different
backends, but actually requires various cross calls.

Rewrite the code to do the generic swiotlb/swiotlb-xen setup directly
in pci-dma.c and then just call into the IOMMU drivers.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
parent f39f8d0e

arch/ia64/include/asm/iommu_table.h

deleted100644 → 0
+0 −7
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _ASM_IA64_IOMMU_TABLE_H

#define _ASM_IA64_IOMMU_TABLE_H



#define IOMMU_INIT_POST(_detect)



#endif /* _ASM_IA64_IOMMU_TABLE_H */

arch/x86/include/asm/dma-mapping.h

+0 −1
Original line number Diff line number Diff line
@@ -9,7 +9,6 @@ 


#include <linux/scatterlist.h>

#include <asm/io.h>

#include <asm/swiotlb.h>



extern int iommu_merge;

extern int panic_on_overflow;

arch/x86/include/asm/gart.h

+2 −3
Original line number Diff line number Diff line
@@ -38,7 +38,7 @@ extern int gart_iommu_aperture_disabled; 
extern void early_gart_iommu_check(void);

extern int gart_iommu_init(void);

extern void __init gart_parse_options(char *);

extern int gart_iommu_hole_init(void);

void gart_iommu_hole_init(void);



#else

#define gart_iommu_aperture            0
@@ -51,9 +51,8 @@ static inline void early_gart_iommu_check(void) 
static inline void gart_parse_options(char *options)

{

}

static inline int gart_iommu_hole_init(void)

static inline void gart_iommu_hole_init(void)

{

	return -ENODEV;

}

#endif

arch/x86/include/asm/iommu.h

+6 −0
Original line number Diff line number Diff line
@@ -9,6 +9,12 @@ 
extern int force_iommu, no_iommu;

extern int iommu_detected;



#ifdef CONFIG_SWIOTLB

extern bool x86_swiotlb_enable;

#else

#define x86_swiotlb_enable false

#endif



/* 10 seconds */

#define DMAR_OPERATION_TIMEOUT ((cycles_t) tsc_khz*10*1000)

arch/x86/include/asm/iommu_table.h

deleted100644 → 0
+0 −102
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _ASM_X86_IOMMU_TABLE_H

#define _ASM_X86_IOMMU_TABLE_H



#include <asm/swiotlb.h>



/*

 * History lesson:

 * The execution chain of IOMMUs in 2.6.36 looks as so:

 *

 *            [xen-swiotlb]

 *                 |

 *         +----[swiotlb *]--+

 *        /         |         \

 *       /          |          \

 *    [GART]     [Calgary]  [Intel VT-d]

 *     /

 *    /

 * [AMD-Vi]

 *

 * *: if SWIOTLB detected 'iommu=soft'/'swiotlb=force' it would skip

 * over the rest of IOMMUs and unconditionally initialize the SWIOTLB.

 * Also it would surreptitiously initialize set the swiotlb=1 if there were

 * more than 4GB and if the user did not pass in 'iommu=off'. The swiotlb

 * flag would be turned off by all IOMMUs except the Calgary one.

 *

 * The IOMMU_INIT* macros allow a similar tree (or more complex if desired)

 * to be built by defining who we depend on.

 *

 * And all that needs to be done is to use one of the macros in the IOMMU

 * and the pci-dma.c will take care of the rest.

 */



struct iommu_table_entry {

	initcall_t	detect;

	initcall_t	depend;

	void		(*early_init)(void); /* No memory allocate available. */

	void		(*late_init)(void); /* Yes, can allocate memory. */

#define IOMMU_FINISH_IF_DETECTED (1<<0)

#define IOMMU_DETECTED		 (1<<1)

	int		flags;

};

/*

 * Macro fills out an entry in the .iommu_table that is equivalent

 * to the fields that 'struct iommu_table_entry' has. The entries

 * that are put in the .iommu_table section are not put in any order

 * hence during boot-time we will have to resort them based on

 * dependency. */





#define __IOMMU_INIT(_detect, _depend, _early_init, _late_init, _finish)\

	static const struct iommu_table_entry				\

		__iommu_entry_##_detect __used				\

	__attribute__ ((unused, __section__(".iommu_table"),		\

			aligned((sizeof(void *)))))	\

	= {_detect, _depend, _early_init, _late_init,			\

	   _finish ? IOMMU_FINISH_IF_DETECTED : 0}

/*

 * The simplest IOMMU definition. Provide the detection routine

 * and it will be run after the SWIOTLB and the other IOMMUs

 * that utilize this macro. If the IOMMU is detected (ie, the

 * detect routine returns a positive value), the other IOMMUs

 * are also checked. You can use IOMMU_INIT_POST_FINISH if you prefer

 * to stop detecting the other IOMMUs after yours has been detected.

 */

#define IOMMU_INIT_POST(_detect)					\

	__IOMMU_INIT(_detect, pci_swiotlb_detect_4gb,  NULL, NULL, 0)



#define IOMMU_INIT_POST_FINISH(detect)					\

	__IOMMU_INIT(_detect, pci_swiotlb_detect_4gb,  NULL, NULL, 1)



/*

 * A more sophisticated version of IOMMU_INIT. This variant requires:

 *  a). A detection routine function.

 *  b). The name of the detection routine we depend on to get called

 *      before us.

 *  c). The init routine which gets called if the detection routine

 *      returns a positive value from the pci_iommu_alloc. This means

 *      no presence of a memory allocator.

 *  d). Similar to the 'init', except that this gets called from pci_iommu_init

 *      where we do have a memory allocator.

 *

 * The standard IOMMU_INIT differs from the IOMMU_INIT_FINISH variant

 * in that the former will continue detecting other IOMMUs in the call

 * list after the detection routine returns a positive number, while the

 * latter will stop the execution chain upon first successful detection.

 * Both variants will still call the 'init' and 'late_init' functions if

 * they are set.

 */

#define IOMMU_INIT_FINISH(_detect, _depend, _init, _late_init)		\

	__IOMMU_INIT(_detect, _depend, _init, _late_init, 1)



#define IOMMU_INIT(_detect, _depend, _init, _late_init)			\

	__IOMMU_INIT(_detect, _depend, _init, _late_init, 0)



void sort_iommu_table(struct iommu_table_entry *start,

		      struct iommu_table_entry *finish);



void check_iommu_entries(struct iommu_table_entry *start,

			 struct iommu_table_entry *finish);



#endif /* _ASM_X86_IOMMU_TABLE_H */