kernel-ark/drivers/pci/iova.h
Keshavamurthy, Anil S f76aec76ec intel-iommu: optimize sg map/unmap calls
This patch adds PageSelectiveInvalidation support replacing existing
DomainSelectiveInvalidation for intel_{map/unmap}_sg() calls and also
enables to mapping one big contiguous DMA virtual address which is mapped
to discontiguous physical address for SG map/unmap calls.

"Doamin selective invalidations" wipes out the IOMMU address translation
cache based on domain ID where as "Page selective invalidations" wipes out
the IOMMU address translation cache for that address mask range which is
more cache friendly when compared to Domain selective invalidations.

Here is how it is done.
1) changes to iova.c
alloc_iova() now takes a bool size_aligned argument, which
when when set, returns the io virtual address that is
naturally aligned to 2 ^ x, where x is the order
of the size requested.

Returning this io vitual address which is naturally
aligned helps iommu to do the "page selective
invalidations" which is IOMMU cache friendly
over "domain selective invalidations".

2) Changes to driver/pci/intel-iommu.c
Clean up intel_{map/unmap}_{single/sg} () calls so that
s/g map/unamp calls is no more dependent on
intel_{map/unmap}_single()

intel_map_sg() now computes the total DMA virtual address
required and allocates the size aligned total DMA virtual address
and maps the discontiguous physical address to the allocated
contiguous DMA virtual address.

In the intel_unmap_sg() case since the DMA virtual address
is contiguous and size_aligned, PageSelectiveInvalidation
is used replacing earlier DomainSelectiveInvalidations.

Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Greg KH <greg@kroah.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Suresh B <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-22 08:13:19 -07:00

64 lines
2.0 KiB
C

/*
* Copyright (c) 2006, Intel Corporation.
*
* This file is released under the GPLv2.
*
* Copyright (C) 2006 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
*
*/
#ifndef _IOVA_H_
#define _IOVA_H_
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/rbtree.h>
#include <linux/dma-mapping.h>
/*
* We need a fixed PAGE_SIZE of 4K irrespective of
* arch PAGE_SIZE for IOMMU page tables.
*/
#define PAGE_SHIFT_4K (12)
#define PAGE_SIZE_4K (1UL << PAGE_SHIFT_4K)
#define PAGE_MASK_4K (((u64)-1) << PAGE_SHIFT_4K)
#define PAGE_ALIGN_4K(addr) (((addr) + PAGE_SIZE_4K - 1) & PAGE_MASK_4K)
/* IO virtual address start page frame number */
#define IOVA_START_PFN (1)
#define IOVA_PFN(addr) ((addr) >> PAGE_SHIFT_4K)
#define DMA_32BIT_PFN IOVA_PFN(DMA_32BIT_MASK)
#define DMA_64BIT_PFN IOVA_PFN(DMA_64BIT_MASK)
/* iova structure */
struct iova {
struct rb_node node;
unsigned long pfn_hi; /* IOMMU dish out addr hi */
unsigned long pfn_lo; /* IOMMU dish out addr lo */
};
/* holds all the iova translations for a domain */
struct iova_domain {
spinlock_t iova_alloc_lock;/* Lock to protect iova allocation */
spinlock_t iova_rbtree_lock; /* Lock to protect update of rbtree */
struct rb_root rbroot; /* iova domain rbtree root */
struct rb_node *cached32_node; /* Save last alloced node */
};
struct iova *alloc_iova_mem(void);
void free_iova_mem(struct iova *iova);
void free_iova(struct iova_domain *iovad, unsigned long pfn);
void __free_iova(struct iova_domain *iovad, struct iova *iova);
struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
unsigned long limit_pfn,
bool size_aligned);
struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
unsigned long pfn_hi);
void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
void init_iova_domain(struct iova_domain *iovad);
struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
void put_iova_domain(struct iova_domain *iovad);
#endif