Re: [Patch Part3 V1 19/22] iommu/vt-d: simplify intel_unmap_sg() and kill duplicated code
On 2014/4/22 15:38, David Woodhouse wrote: > On Tue, 2014-04-22 at 15:07 +0800, Jiang Liu wrote: >> + size_t size = 0; >> +#if 0 >> + /* current the third argument of intel_unmap_page is unsued */ >> + int i; >> + struct scatterlist *sg; >> >> - freelist = domain_unmap(domain, start_pfn, last_pfn); >> + for_each_sg(sglist, sg, nelems, i) >> + size += sg->length; >> +#endif > > Please don't do that. If you want to rely on the fact that > intel_unmap_page() currently just uses the size from the IOVA it finds, > then split it out into a separate function which explicitly does > precisely that. And call that new function from both intel_unmap_sg() > and intel_unmap_page(). Good suggestion, will change to follow that way in next version. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Patch Part3 V1 19/22] iommu/vt-d: simplify intel_unmap_sg() and kill duplicated code
On Tue, 2014-04-22 at 15:07 +0800, Jiang Liu wrote: > + size_t size = 0; > +#if 0 > + /* current the third argument of intel_unmap_page is unsued */ > + int i; > + struct scatterlist *sg; > > - freelist = domain_unmap(domain, start_pfn, last_pfn); > + for_each_sg(sglist, sg, nelems, i) > + size += sg->length; > +#endif Please don't do that. If you want to rely on the fact that intel_unmap_page() currently just uses the size from the IOVA it finds, then split it out into a separate function which explicitly does precisely that. And call that new function from both intel_unmap_sg() and intel_unmap_page(). -- David WoodhouseOpen Source Technology Centre david.woodho...@intel.com Intel Corporation smime.p7s Description: S/MIME cryptographic signature
[Patch Part3 V1 19/22] iommu/vt-d: simplify intel_unmap_sg() and kill duplicated code
Simplify intel_unmap_sg() by calling intel_unmap_page() and
kill duplicated code, no functionality changes.
Signed-off-by: Jiang Liu
---
drivers/iommu/intel-iommu.c | 63 +--
1 file changed, 18 insertions(+), 45 deletions(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index f2143b59ad68..4738e64fe097 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -979,6 +979,8 @@ static void dma_pte_free_pagetable(struct dmar_domain
*domain,
BUG_ON(addr_width < BITS_PER_LONG && last_pfn >> addr_width);
BUG_ON(start_pfn > last_pfn);
+ dma_pte_clear_range(domain, start_pfn, last_pfn);
+
/* We don't need lock here; nobody else touches the iova range */
dma_pte_free_level(domain, agaw_to_level(domain->agaw),
domain->pgd, 0, start_pfn, last_pfn);
@@ -2031,12 +2033,14 @@ static int __domain_mapping(struct dmar_domain *domain,
unsigned long iov_pfn,
/* It is large page*/
if (largepage_lvl > 1) {
pteval |= DMA_PTE_LARGE_PAGE;
- /* Ensure that old small page tables are
removed to make room
- for superpage, if they exist. */
- dma_pte_clear_range(domain, iov_pfn,
- iov_pfn +
lvl_to_nr_pages(largepage_lvl) - 1);
+ lvl_pages = lvl_to_nr_pages(largepage_lvl);
+ /*
+* Ensure that old small page tables are
+* removed to make room for superpage,
+* if they exist.
+*/
dma_pte_free_pagetable(domain, iov_pfn,
- iov_pfn +
lvl_to_nr_pages(largepage_lvl) - 1);
+ iov_pfn + lvl_pages - 1);
} else {
pteval &= ~(uint64_t)DMA_PTE_LARGE_PAGE;
}
@@ -3256,43 +3260,17 @@ static void intel_unmap_sg(struct device *dev, struct
scatterlist *sglist,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
- struct dmar_domain *domain;
- unsigned long start_pfn, last_pfn;
- struct iova *iova;
- struct intel_iommu *iommu;
- struct page *freelist;
-
- if (iommu_no_mapping(dev))
- return;
-
- domain = find_domain(dev);
- BUG_ON(!domain);
-
- iommu = domain_get_iommu(domain);
-
- iova = find_iova(>iovad, IOVA_PFN(sglist[0].dma_address));
- if (WARN_ONCE(!iova, "Driver unmaps unmatched sglist at PFN %llx\n",
- (unsigned long long)sglist[0].dma_address))
- return;
-
- start_pfn = mm_to_dma_pfn(iova->pfn_lo);
- last_pfn = mm_to_dma_pfn(iova->pfn_hi + 1) - 1;
+ size_t size = 0;
+#if 0
+ /* current the third argument of intel_unmap_page is unsued */
+ int i;
+ struct scatterlist *sg;
- freelist = domain_unmap(domain, start_pfn, last_pfn);
+ for_each_sg(sglist, sg, nelems, i)
+ size += sg->length;
+#endif
- if (intel_iommu_strict) {
- iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
- last_pfn - start_pfn + 1, !freelist, 0);
- /* free iova */
- __free_iova(>iovad, iova);
- dma_free_pagelist(freelist);
- } else {
- add_unmap(domain, iova, freelist);
- /*
-* queue up the release of the unmap to save the 1/6th of the
-* cpu used up by the iotlb flush operation...
-*/
- }
+ intel_unmap_page(dev, sglist[0].dma_address, size, dir, attrs);
}
static int intel_nontranslate_map_sg(struct device *hddev,
@@ -3356,13 +3334,8 @@ static int intel_map_sg(struct device *dev, struct
scatterlist *sglist, int nele
ret = domain_sg_mapping(domain, start_vpfn, sglist, size, prot);
if (unlikely(ret)) {
- /* clear the page */
- dma_pte_clear_range(domain, start_vpfn,
- start_vpfn + size - 1);
- /* free page tables */
dma_pte_free_pagetable(domain, start_vpfn,
start_vpfn + size - 1);
- /* free iova */
__free_iova(>iovad, iova);
return 0;
}
--
1.7.10.4
--
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Please read the FAQ
[Patch Part3 V1 19/22] iommu/vt-d: simplify intel_unmap_sg() and kill duplicated code
Simplify intel_unmap_sg() by calling intel_unmap_page() and
kill duplicated code, no functionality changes.
Signed-off-by: Jiang Liu jiang@linux.intel.com
---
drivers/iommu/intel-iommu.c | 63 +--
1 file changed, 18 insertions(+), 45 deletions(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index f2143b59ad68..4738e64fe097 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -979,6 +979,8 @@ static void dma_pte_free_pagetable(struct dmar_domain
*domain,
BUG_ON(addr_width BITS_PER_LONG last_pfn addr_width);
BUG_ON(start_pfn last_pfn);
+ dma_pte_clear_range(domain, start_pfn, last_pfn);
+
/* We don't need lock here; nobody else touches the iova range */
dma_pte_free_level(domain, agaw_to_level(domain-agaw),
domain-pgd, 0, start_pfn, last_pfn);
@@ -2031,12 +2033,14 @@ static int __domain_mapping(struct dmar_domain *domain,
unsigned long iov_pfn,
/* It is large page*/
if (largepage_lvl 1) {
pteval |= DMA_PTE_LARGE_PAGE;
- /* Ensure that old small page tables are
removed to make room
- for superpage, if they exist. */
- dma_pte_clear_range(domain, iov_pfn,
- iov_pfn +
lvl_to_nr_pages(largepage_lvl) - 1);
+ lvl_pages = lvl_to_nr_pages(largepage_lvl);
+ /*
+* Ensure that old small page tables are
+* removed to make room for superpage,
+* if they exist.
+*/
dma_pte_free_pagetable(domain, iov_pfn,
- iov_pfn +
lvl_to_nr_pages(largepage_lvl) - 1);
+ iov_pfn + lvl_pages - 1);
} else {
pteval = ~(uint64_t)DMA_PTE_LARGE_PAGE;
}
@@ -3256,43 +3260,17 @@ static void intel_unmap_sg(struct device *dev, struct
scatterlist *sglist,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
- struct dmar_domain *domain;
- unsigned long start_pfn, last_pfn;
- struct iova *iova;
- struct intel_iommu *iommu;
- struct page *freelist;
-
- if (iommu_no_mapping(dev))
- return;
-
- domain = find_domain(dev);
- BUG_ON(!domain);
-
- iommu = domain_get_iommu(domain);
-
- iova = find_iova(domain-iovad, IOVA_PFN(sglist[0].dma_address));
- if (WARN_ONCE(!iova, Driver unmaps unmatched sglist at PFN %llx\n,
- (unsigned long long)sglist[0].dma_address))
- return;
-
- start_pfn = mm_to_dma_pfn(iova-pfn_lo);
- last_pfn = mm_to_dma_pfn(iova-pfn_hi + 1) - 1;
+ size_t size = 0;
+#if 0
+ /* current the third argument of intel_unmap_page is unsued */
+ int i;
+ struct scatterlist *sg;
- freelist = domain_unmap(domain, start_pfn, last_pfn);
+ for_each_sg(sglist, sg, nelems, i)
+ size += sg-length;
+#endif
- if (intel_iommu_strict) {
- iommu_flush_iotlb_psi(iommu, domain-id, start_pfn,
- last_pfn - start_pfn + 1, !freelist, 0);
- /* free iova */
- __free_iova(domain-iovad, iova);
- dma_free_pagelist(freelist);
- } else {
- add_unmap(domain, iova, freelist);
- /*
-* queue up the release of the unmap to save the 1/6th of the
-* cpu used up by the iotlb flush operation...
-*/
- }
+ intel_unmap_page(dev, sglist[0].dma_address, size, dir, attrs);
}
static int intel_nontranslate_map_sg(struct device *hddev,
@@ -3356,13 +3334,8 @@ static int intel_map_sg(struct device *dev, struct
scatterlist *sglist, int nele
ret = domain_sg_mapping(domain, start_vpfn, sglist, size, prot);
if (unlikely(ret)) {
- /* clear the page */
- dma_pte_clear_range(domain, start_vpfn,
- start_vpfn + size - 1);
- /* free page tables */
dma_pte_free_pagetable(domain, start_vpfn,
start_vpfn + size - 1);
- /* free iova */
__free_iova(domain-iovad, iova);
return 0;
}
--
1.7.10.4
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Re: [Patch Part3 V1 19/22] iommu/vt-d: simplify intel_unmap_sg() and kill duplicated code
On Tue, 2014-04-22 at 15:07 +0800, Jiang Liu wrote: + size_t size = 0; +#if 0 + /* current the third argument of intel_unmap_page is unsued */ + int i; + struct scatterlist *sg; - freelist = domain_unmap(domain, start_pfn, last_pfn); + for_each_sg(sglist, sg, nelems, i) + size += sg-length; +#endif Please don't do that. If you want to rely on the fact that intel_unmap_page() currently just uses the size from the IOVA it finds, then split it out into a separate function which explicitly does precisely that. And call that new function from both intel_unmap_sg() and intel_unmap_page(). -- David WoodhouseOpen Source Technology Centre david.woodho...@intel.com Intel Corporation smime.p7s Description: S/MIME cryptographic signature
Re: [Patch Part3 V1 19/22] iommu/vt-d: simplify intel_unmap_sg() and kill duplicated code
On 2014/4/22 15:38, David Woodhouse wrote: On Tue, 2014-04-22 at 15:07 +0800, Jiang Liu wrote: + size_t size = 0; +#if 0 + /* current the third argument of intel_unmap_page is unsued */ + int i; + struct scatterlist *sg; - freelist = domain_unmap(domain, start_pfn, last_pfn); + for_each_sg(sglist, sg, nelems, i) + size += sg-length; +#endif Please don't do that. If you want to rely on the fact that intel_unmap_page() currently just uses the size from the IOVA it finds, then split it out into a separate function which explicitly does precisely that. And call that new function from both intel_unmap_sg() and intel_unmap_page(). Good suggestion, will change to follow that way in next version. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
