| Message ID | 20220725141833.1970029-1-bob.beckett@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4] drm/i915: stop using swiotlb | expand |
On 25/07/2022 15:18, Robert Beckett wrote: > Calling swiotlb functions directly is nowadays considered harmful. See > https://lore.kernel.org/intel-gfx/20220711082614.GA29487@lst.de/ > > Replace swiotlb_max_segment() calls with dma_max_mapping_size(). > In i915_gem_object_get_pages_internal() no longer consider max_segment > only if CONFIG_SWIOTLB is enabled. There can be other (iommu related) > causes of specific max segment sizes. > > Cc: Christoph Hellwig <hch@lst.de> > Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> > Cc: Thomas Hellstrom <thomas.hellstrom@intel.com> > Cc: Matthew Auld <matthew.auld@intel.com> > > v2: - restore UINT_MAX clamp in i915_sg_segment_size() > - drop PAGE_SIZE check as it will always be >= PAGE_SIZE > v3: - actually clamp to UINT_MAX in i915_sg_segment_size() > v4: - round down max segment size to PAGE_SIZE > > Reviewed-by: Christoph Hellwig <hch@lst.de> > Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> > Signed-off-by: Robert Beckett <bob.beckett@collabora.com> > --- > drivers/gpu/drm/i915/gem/i915_gem_internal.c | 19 ++++--------------- > drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 2 +- > drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 4 ++-- > drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 2 +- > drivers/gpu/drm/i915/i915_scatterlist.h | 17 ++++------------- > 5 files changed, 12 insertions(+), 32 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c b/drivers/gpu/drm/i915/gem/i915_gem_internal.c > index c698f95af15f..24f37658f1bb 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c > @@ -6,7 +6,6 @@ > > #include <linux/scatterlist.h> > #include <linux/slab.h> > -#include <linux/swiotlb.h> > > #include "i915_drv.h" > #include "i915_gem.h" > @@ -38,22 +37,12 @@ static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj) > struct scatterlist *sg; > unsigned int sg_page_sizes; > unsigned int npages; > - int max_order; > + int max_order = MAX_ORDER; > + unsigned int max_segment; > gfp_t gfp; > > - max_order = MAX_ORDER; > -#ifdef CONFIG_SWIOTLB > - if (is_swiotlb_active(obj->base.dev->dev)) { > - unsigned int max_segment; > - > - max_segment = swiotlb_max_segment(); > - if (max_segment) { > - max_segment = max_t(unsigned int, max_segment, > - PAGE_SIZE) >> PAGE_SHIFT; > - max_order = min(max_order, ilog2(max_segment)); > - } > - } > -#endif > + max_segment = i915_sg_segment_size(i915->drm.dev) >> PAGE_SHIFT; > + max_order = min(max_order, ilog2(max_segment)); > > gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_RECLAIMABLE; > if (IS_I965GM(i915) || IS_I965G(i915)) { > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c > index 4eed3dd90ba8..34b9c76cd8e6 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c > @@ -194,7 +194,7 @@ static int shmem_get_pages(struct drm_i915_gem_object *obj) > struct intel_memory_region *mem = obj->mm.region; > struct address_space *mapping = obj->base.filp->f_mapping; > const unsigned long page_count = obj->base.size / PAGE_SIZE; > - unsigned int max_segment = i915_sg_segment_size(); > + unsigned int max_segment = i915_sg_segment_size(i915->drm.dev); > struct sg_table *st; > struct sgt_iter sgt_iter; > struct page *page; > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c > index 5a5cf332d8a5..7a828c9c0f6d 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c > @@ -189,7 +189,7 @@ static int i915_ttm_tt_shmem_populate(struct ttm_device *bdev, > struct drm_i915_private *i915 = container_of(bdev, typeof(*i915), bdev); > struct intel_memory_region *mr = i915->mm.regions[INTEL_MEMORY_SYSTEM]; > struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); > - const unsigned int max_segment = i915_sg_segment_size(); > + const unsigned int max_segment = i915_sg_segment_size(i915->drm.dev); > const size_t size = (size_t)ttm->num_pages << PAGE_SHIFT; > struct file *filp = i915_tt->filp; > struct sgt_iter sgt_iter; > @@ -568,7 +568,7 @@ static struct i915_refct_sgt *i915_ttm_tt_get_st(struct ttm_tt *ttm) > ret = sg_alloc_table_from_pages_segment(st, > ttm->pages, ttm->num_pages, > 0, (unsigned long)ttm->num_pages << PAGE_SHIFT, > - i915_sg_segment_size(), GFP_KERNEL); > + i915_sg_segment_size(i915_tt->dev), GFP_KERNEL); > if (ret) { > st->sgl = NULL; > return ERR_PTR(ret); > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c > index 094f06b4ce33..dfc35905dba2 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c > @@ -129,7 +129,7 @@ static void i915_gem_object_userptr_drop_ref(struct drm_i915_gem_object *obj) > static int i915_gem_userptr_get_pages(struct drm_i915_gem_object *obj) > { > const unsigned long num_pages = obj->base.size >> PAGE_SHIFT; > - unsigned int max_segment = i915_sg_segment_size(); > + unsigned int max_segment = i915_sg_segment_size(obj->base.dev->dev); > struct sg_table *st; > unsigned int sg_page_sizes; > struct page **pvec; > diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h b/drivers/gpu/drm/i915/i915_scatterlist.h > index 9ddb3e743a3e..1377a97a20cf 100644 > --- a/drivers/gpu/drm/i915/i915_scatterlist.h > +++ b/drivers/gpu/drm/i915/i915_scatterlist.h > @@ -9,7 +9,7 @@ > > #include <linux/pfn.h> > #include <linux/scatterlist.h> > -#include <linux/swiotlb.h> > +#include <linux/dma-mapping.h> > > #include "i915_gem.h" > > @@ -127,19 +127,10 @@ static inline unsigned int i915_sg_dma_sizes(struct scatterlist *sg) > return page_sizes; > } > > -static inline unsigned int i915_sg_segment_size(void) > +static inline unsigned int i915_sg_segment_size(struct device *dev) > { > - unsigned int size = swiotlb_max_segment(); > - > - if (size == 0) > - size = UINT_MAX; > - > - size = rounddown(size, PAGE_SIZE); > - /* swiotlb_max_segment_size can return 1 byte when it means one page. */ > - if (size < PAGE_SIZE) > - size = PAGE_SIZE; > - > - return size; > + size_t max = min_t(size_t, UINT_MAX, dma_max_mapping_size(dev)); Hope your patience is not growing thin but blank line here as per checkpatch. I could fudge when applying though. Otherwise it finally passed CI, yay! Now do we dig deeper to a) understand how/where it failed and b) check what are the possible return values from dma_max_mapping_size(), or call it done? Regards, Tvrtko > + return round_down(max, PAGE_SIZE); > } > > bool i915_sg_trim(struct sg_table *orig_st);
On 26/07/2022 14:12, Tvrtko Ursulin wrote: > > On 25/07/2022 15:18, Robert Beckett wrote: >> Calling swiotlb functions directly is nowadays considered harmful. See >> https://lore.kernel.org/intel-gfx/20220711082614.GA29487@lst.de/ >> >> Replace swiotlb_max_segment() calls with dma_max_mapping_size(). >> In i915_gem_object_get_pages_internal() no longer consider max_segment >> only if CONFIG_SWIOTLB is enabled. There can be other (iommu related) >> causes of specific max segment sizes. >> >> Cc: Christoph Hellwig <hch@lst.de> >> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> >> Cc: Thomas Hellstrom <thomas.hellstrom@intel.com> >> Cc: Matthew Auld <matthew.auld@intel.com> >> >> v2: - restore UINT_MAX clamp in i915_sg_segment_size() >> - drop PAGE_SIZE check as it will always be >= PAGE_SIZE >> v3: - actually clamp to UINT_MAX in i915_sg_segment_size() >> v4: - round down max segment size to PAGE_SIZE >> >> Reviewed-by: Christoph Hellwig <hch@lst.de> >> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> >> Signed-off-by: Robert Beckett <bob.beckett@collabora.com> >> --- >> drivers/gpu/drm/i915/gem/i915_gem_internal.c | 19 ++++--------------- >> drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 2 +- >> drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 4 ++-- >> drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 2 +- >> drivers/gpu/drm/i915/i915_scatterlist.h | 17 ++++------------- >> 5 files changed, 12 insertions(+), 32 deletions(-) >> >> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c >> b/drivers/gpu/drm/i915/gem/i915_gem_internal.c >> index c698f95af15f..24f37658f1bb 100644 >> --- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c >> +++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c >> @@ -6,7 +6,6 @@ >> #include <linux/scatterlist.h> >> #include <linux/slab.h> >> -#include <linux/swiotlb.h> >> #include "i915_drv.h" >> #include "i915_gem.h" >> @@ -38,22 +37,12 @@ static int >> i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj) >> struct scatterlist *sg; >> unsigned int sg_page_sizes; >> unsigned int npages; >> - int max_order; >> + int max_order = MAX_ORDER; >> + unsigned int max_segment; >> gfp_t gfp; >> - max_order = MAX_ORDER; >> -#ifdef CONFIG_SWIOTLB >> - if (is_swiotlb_active(obj->base.dev->dev)) { >> - unsigned int max_segment; >> - >> - max_segment = swiotlb_max_segment(); >> - if (max_segment) { >> - max_segment = max_t(unsigned int, max_segment, >> - PAGE_SIZE) >> PAGE_SHIFT; >> - max_order = min(max_order, ilog2(max_segment)); >> - } >> - } >> -#endif >> + max_segment = i915_sg_segment_size(i915->drm.dev) >> PAGE_SHIFT; >> + max_order = min(max_order, ilog2(max_segment)); >> gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_RECLAIMABLE; >> if (IS_I965GM(i915) || IS_I965G(i915)) { >> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c >> b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c >> index 4eed3dd90ba8..34b9c76cd8e6 100644 >> --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c >> +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c >> @@ -194,7 +194,7 @@ static int shmem_get_pages(struct >> drm_i915_gem_object *obj) >> struct intel_memory_region *mem = obj->mm.region; >> struct address_space *mapping = obj->base.filp->f_mapping; >> const unsigned long page_count = obj->base.size / PAGE_SIZE; >> - unsigned int max_segment = i915_sg_segment_size(); >> + unsigned int max_segment = i915_sg_segment_size(i915->drm.dev); >> struct sg_table *st; >> struct sgt_iter sgt_iter; >> struct page *page; >> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c >> b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c >> index 5a5cf332d8a5..7a828c9c0f6d 100644 >> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c >> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c >> @@ -189,7 +189,7 @@ static int i915_ttm_tt_shmem_populate(struct >> ttm_device *bdev, >> struct drm_i915_private *i915 = container_of(bdev, >> typeof(*i915), bdev); >> struct intel_memory_region *mr = >> i915->mm.regions[INTEL_MEMORY_SYSTEM]; >> struct i915_ttm_tt *i915_tt = container_of(ttm, >> typeof(*i915_tt), ttm); >> - const unsigned int max_segment = i915_sg_segment_size(); >> + const unsigned int max_segment = >> i915_sg_segment_size(i915->drm.dev); >> const size_t size = (size_t)ttm->num_pages << PAGE_SHIFT; >> struct file *filp = i915_tt->filp; >> struct sgt_iter sgt_iter; >> @@ -568,7 +568,7 @@ static struct i915_refct_sgt >> *i915_ttm_tt_get_st(struct ttm_tt *ttm) >> ret = sg_alloc_table_from_pages_segment(st, >> ttm->pages, ttm->num_pages, >> 0, (unsigned long)ttm->num_pages << PAGE_SHIFT, >> - i915_sg_segment_size(), GFP_KERNEL); >> + i915_sg_segment_size(i915_tt->dev), GFP_KERNEL); >> if (ret) { >> st->sgl = NULL; >> return ERR_PTR(ret); >> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c >> b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c >> index 094f06b4ce33..dfc35905dba2 100644 >> --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c >> +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c >> @@ -129,7 +129,7 @@ static void >> i915_gem_object_userptr_drop_ref(struct drm_i915_gem_object *obj) >> static int i915_gem_userptr_get_pages(struct drm_i915_gem_object *obj) >> { >> const unsigned long num_pages = obj->base.size >> PAGE_SHIFT; >> - unsigned int max_segment = i915_sg_segment_size(); >> + unsigned int max_segment = i915_sg_segment_size(obj->base.dev->dev); >> struct sg_table *st; >> unsigned int sg_page_sizes; >> struct page **pvec; >> diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h >> b/drivers/gpu/drm/i915/i915_scatterlist.h >> index 9ddb3e743a3e..1377a97a20cf 100644 >> --- a/drivers/gpu/drm/i915/i915_scatterlist.h >> +++ b/drivers/gpu/drm/i915/i915_scatterlist.h >> @@ -9,7 +9,7 @@ >> #include <linux/pfn.h> >> #include <linux/scatterlist.h> >> -#include <linux/swiotlb.h> >> +#include <linux/dma-mapping.h> >> #include "i915_gem.h" >> @@ -127,19 +127,10 @@ static inline unsigned int >> i915_sg_dma_sizes(struct scatterlist *sg) >> return page_sizes; >> } >> -static inline unsigned int i915_sg_segment_size(void) >> +static inline unsigned int i915_sg_segment_size(struct device *dev) >> { >> - unsigned int size = swiotlb_max_segment(); >> - >> - if (size == 0) >> - size = UINT_MAX; >> - >> - size = rounddown(size, PAGE_SIZE); >> - /* swiotlb_max_segment_size can return 1 byte when it means one >> page. */ >> - if (size < PAGE_SIZE) >> - size = PAGE_SIZE; >> - >> - return size; >> + size_t max = min_t(size_t, UINT_MAX, dma_max_mapping_size(dev)); > > Hope your patience is not growing thin but blank line here as per > checkpatch. I could fudge when applying though. no worries, I'll issue a new version shortly. I only recently guided a mentee to "always do your checkpatch, even if only doing a quick 1 character change, you never know if it you make a small mistake" I guess do as I say, not as I do applies here :) > > Otherwise it finally passed CI, yay! Now do we dig deeper to a) > understand how/where it failed and b) check what are the possible return > values from dma_max_mapping_size(), or call it done? I will have to call it done myself as I am unable to repo it locally. I could spend a lot of time debugging it via trybot, but I expect it will be easier, quicker and cheaper to get someone with local hw with a repro case to debug it if you want to root cause it. > > Regards, > > Tvrtko > >> + return round_down(max, PAGE_SIZE); >> } >> bool i915_sg_trim(struct sg_table *orig_st);
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c b/drivers/gpu/drm/i915/gem/i915_gem_internal.c index c698f95af15f..24f37658f1bb 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c @@ -6,7 +6,6 @@ #include <linux/scatterlist.h> #include <linux/slab.h> -#include <linux/swiotlb.h> #include "i915_drv.h" #include "i915_gem.h" @@ -38,22 +37,12 @@ static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj) struct scatterlist *sg; unsigned int sg_page_sizes; unsigned int npages; - int max_order; + int max_order = MAX_ORDER; + unsigned int max_segment; gfp_t gfp; - max_order = MAX_ORDER; -#ifdef CONFIG_SWIOTLB - if (is_swiotlb_active(obj->base.dev->dev)) { - unsigned int max_segment; - - max_segment = swiotlb_max_segment(); - if (max_segment) { - max_segment = max_t(unsigned int, max_segment, - PAGE_SIZE) >> PAGE_SHIFT; - max_order = min(max_order, ilog2(max_segment)); - } - } -#endif + max_segment = i915_sg_segment_size(i915->drm.dev) >> PAGE_SHIFT; + max_order = min(max_order, ilog2(max_segment)); gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_RECLAIMABLE; if (IS_I965GM(i915) || IS_I965G(i915)) { diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c index 4eed3dd90ba8..34b9c76cd8e6 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c @@ -194,7 +194,7 @@ static int shmem_get_pages(struct drm_i915_gem_object *obj) struct intel_memory_region *mem = obj->mm.region; struct address_space *mapping = obj->base.filp->f_mapping; const unsigned long page_count = obj->base.size / PAGE_SIZE; - unsigned int max_segment = i915_sg_segment_size(); + unsigned int max_segment = i915_sg_segment_size(i915->drm.dev); struct sg_table *st; struct sgt_iter sgt_iter; struct page *page; diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c index 5a5cf332d8a5..7a828c9c0f6d 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c @@ -189,7 +189,7 @@ static int i915_ttm_tt_shmem_populate(struct ttm_device *bdev, struct drm_i915_private *i915 = container_of(bdev, typeof(*i915), bdev); struct intel_memory_region *mr = i915->mm.regions[INTEL_MEMORY_SYSTEM]; struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); - const unsigned int max_segment = i915_sg_segment_size(); + const unsigned int max_segment = i915_sg_segment_size(i915->drm.dev); const size_t size = (size_t)ttm->num_pages << PAGE_SHIFT; struct file *filp = i915_tt->filp; struct sgt_iter sgt_iter; @@ -568,7 +568,7 @@ static struct i915_refct_sgt *i915_ttm_tt_get_st(struct ttm_tt *ttm) ret = sg_alloc_table_from_pages_segment(st, ttm->pages, ttm->num_pages, 0, (unsigned long)ttm->num_pages << PAGE_SHIFT, - i915_sg_segment_size(), GFP_KERNEL); + i915_sg_segment_size(i915_tt->dev), GFP_KERNEL); if (ret) { st->sgl = NULL; return ERR_PTR(ret); diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c index 094f06b4ce33..dfc35905dba2 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c @@ -129,7 +129,7 @@ static void i915_gem_object_userptr_drop_ref(struct drm_i915_gem_object *obj) static int i915_gem_userptr_get_pages(struct drm_i915_gem_object *obj) { const unsigned long num_pages = obj->base.size >> PAGE_SHIFT; - unsigned int max_segment = i915_sg_segment_size(); + unsigned int max_segment = i915_sg_segment_size(obj->base.dev->dev); struct sg_table *st; unsigned int sg_page_sizes; struct page **pvec; diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h b/drivers/gpu/drm/i915/i915_scatterlist.h index 9ddb3e743a3e..1377a97a20cf 100644 --- a/drivers/gpu/drm/i915/i915_scatterlist.h +++ b/drivers/gpu/drm/i915/i915_scatterlist.h @@ -9,7 +9,7 @@ #include <linux/pfn.h> #include <linux/scatterlist.h> -#include <linux/swiotlb.h> +#include <linux/dma-mapping.h> #include "i915_gem.h" @@ -127,19 +127,10 @@ static inline unsigned int i915_sg_dma_sizes(struct scatterlist *sg) return page_sizes; } -static inline unsigned int i915_sg_segment_size(void) +static inline unsigned int i915_sg_segment_size(struct device *dev) { - unsigned int size = swiotlb_max_segment(); - - if (size == 0) - size = UINT_MAX; - - size = rounddown(size, PAGE_SIZE); - /* swiotlb_max_segment_size can return 1 byte when it means one page. */ - if (size < PAGE_SIZE) - size = PAGE_SIZE; - - return size; + size_t max = min_t(size_t, UINT_MAX, dma_max_mapping_size(dev)); + return round_down(max, PAGE_SIZE); } bool i915_sg_trim(struct sg_table *orig_st);
Calling swiotlb functions directly is nowadays considered harmful. See https://lore.kernel.org/intel-gfx/20220711082614.GA29487@lst.de/ Replace swiotlb_max_segment() calls with dma_max_mapping_size(). In i915_gem_object_get_pages_internal() no longer consider max_segment only if CONFIG_SWIOTLB is enabled. There can be other (iommu related) causes of specific max segment sizes. Cc: Christoph Hellwig <hch@lst.de> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: Thomas Hellstrom <thomas.hellstrom@intel.com> Cc: Matthew Auld <matthew.auld@intel.com> v2: - restore UINT_MAX clamp in i915_sg_segment_size() - drop PAGE_SIZE check as it will always be >= PAGE_SIZE v3: - actually clamp to UINT_MAX in i915_sg_segment_size() v4: - round down max segment size to PAGE_SIZE Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Signed-off-by: Robert Beckett <bob.beckett@collabora.com> --- drivers/gpu/drm/i915/gem/i915_gem_internal.c | 19 ++++--------------- drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 2 +- drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 4 ++-- drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 2 +- drivers/gpu/drm/i915/i915_scatterlist.h | 17 ++++------------- 5 files changed, 12 insertions(+), 32 deletions(-)