| Message ID | 20220126152155.3070602-2-matthew.auld@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Initial support for small BAR recovery | expand |
On Wed, 26 Jan 2022, Matthew Auld <matthew.auld@intel.com> wrote: > From: Arunpravin <Arunpravin.PaneerSelvam@amd.com> > > - Make drm_buddy_alloc a single function to handle > range allocation and non-range allocation demands > > - Implemented a new function alloc_range() which allocates > the requested power-of-two block comply with range limitations > > - Moved order computation and memory alignment logic from > i915 driver to drm buddy > > v2: > merged below changes to keep the build unbroken > - drm_buddy_alloc_range() becomes obsolete and may be removed > - enable ttm range allocation (fpfn / lpfn) support in i915 driver > - apply enhanced drm_buddy_alloc() function to i915 driver > > v3(Matthew Auld): > - Fix alignment issues and remove unnecessary list_empty check > - add more validation checks for input arguments > - make alloc_range() block allocations as bottom-up > - optimize order computation logic > - replace uint64_t with u64, which is preferred in the kernel > > v4(Matthew Auld): > - keep drm_buddy_alloc_range() function implementation for generic > actual range allocations > - keep alloc_range() implementation for end bias allocations > > v5(Matthew Auld): > - modify drm_buddy_alloc() passing argument place->lpfn to lpfn > as place->lpfn will currently always be zero for i915 > > v6(Matthew Auld): > - fixup potential uaf - If we are unlucky and can't allocate > enough memory when splitting blocks, where we temporarily > end up with the given block and its buddy on the respective > free list, then we need to ensure we delete both blocks, > and no just the buddy, before potentially freeing them > > - fix warnings reported by kernel test robot <lkp@intel.com> > > Signed-off-by: Arunpravin <Arunpravin.PaneerSelvam@amd.com> > --- > drivers/gpu/drm/drm_buddy.c | 326 +++++++++++++----- > drivers/gpu/drm/i915/i915_ttm_buddy_manager.c | 67 ++-- > drivers/gpu/drm/i915/i915_ttm_buddy_manager.h | 2 + > include/drm/drm_buddy.h | 22 +- > 4 files changed, 293 insertions(+), 124 deletions(-) > > diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c > index d60878bc9c20..954e31962c74 100644 > --- a/drivers/gpu/drm/drm_buddy.c > +++ b/drivers/gpu/drm/drm_buddy.c > @@ -282,23 +282,99 @@ void drm_buddy_free_list(struct drm_buddy *mm, struct list_head *objects) > } > EXPORT_SYMBOL(drm_buddy_free_list); > > -/** > - * drm_buddy_alloc_blocks - allocate power-of-two blocks > - * > - * @mm: DRM buddy manager to allocate from > - * @order: size of the allocation > - * > - * The order value here translates to: > - * > - * 0 = 2^0 * mm->chunk_size > - * 1 = 2^1 * mm->chunk_size > - * 2 = 2^2 * mm->chunk_size > - * > - * Returns: > - * allocated ptr to the &drm_buddy_block on success > - */ > -struct drm_buddy_block * > -drm_buddy_alloc_blocks(struct drm_buddy *mm, unsigned int order) > +static inline bool overlaps(u64 s1, u64 e1, u64 s2, u64 e2) > +{ > + return s1 <= e2 && e1 >= s2; > +} > + > +static inline bool contains(u64 s1, u64 e1, u64 s2, u64 e2) > +{ > + return s1 <= s2 && e1 >= e2; > +} > + > +static struct drm_buddy_block * > +alloc_range_bias(struct drm_buddy *mm, > + u64 start, u64 end, > + unsigned int order) > +{ > + struct drm_buddy_block *block; > + struct drm_buddy_block *buddy; > + LIST_HEAD(dfs); > + int err; > + int i; > + > + end = end - 1; > + > + for (i = 0; i < mm->n_roots; ++i) > + list_add_tail(&mm->roots[i]->tmp_link, &dfs); > + > + do { > + u64 block_start; > + u64 block_end; > + > + block = list_first_entry_or_null(&dfs, > + struct drm_buddy_block, > + tmp_link); > + if (!block) > + break; > + > + list_del(&block->tmp_link); > + > + if (drm_buddy_block_order(block) < order) > + continue; > + > + block_start = drm_buddy_block_offset(block); > + block_end = block_start + drm_buddy_block_size(mm, block) - 1; > + > + if (!overlaps(start, end, block_start, block_end)) > + continue; > + > + if (drm_buddy_block_is_allocated(block)) > + continue; > + > + if (contains(start, end, block_start, block_end) && > + order == drm_buddy_block_order(block)) { > + /* > + * Find the free block within the range. > + */ > + if (drm_buddy_block_is_free(block)) > + return block; > + > + continue; > + } > + > + if (!drm_buddy_block_is_split(block)) { > + err = split_block(mm, block); > + if (unlikely(err)) > + goto err_undo; > + } > + > + list_add(&block->right->tmp_link, &dfs); > + list_add(&block->left->tmp_link, &dfs); > + } while (1); > + > + return ERR_PTR(-ENOSPC); > + > +err_undo: > + /* > + * We really don't want to leave around a bunch of split blocks, since > + * bigger is better, so make sure we merge everything back before we > + * free the allocated blocks. > + */ > + buddy = get_buddy(block); > + if (buddy && > + (drm_buddy_block_is_free(block) && > + drm_buddy_block_is_free(buddy))) { > + list_del(&block->link); > + __drm_buddy_free(mm, block); > + } > + return ERR_PTR(err); > +} > + > +static struct drm_buddy_block * > +alloc_from_freelist(struct drm_buddy *mm, > + unsigned int order, > + unsigned long flags) > { > struct drm_buddy_block *block = NULL; > unsigned int i; > @@ -320,78 +396,30 @@ drm_buddy_alloc_blocks(struct drm_buddy *mm, unsigned int order) > while (i != order) { > err = split_block(mm, block); > if (unlikely(err)) > - goto out_free; > + goto err_undo; > > - /* Go low */ > - block = block->left; > + block = block->right; > i--; > } > - > - mark_allocated(block); > - mm->avail -= drm_buddy_block_size(mm, block); > - kmemleak_update_trace(block); > return block; > > -out_free: > - if (i != order) > +err_undo: > + if (i != order) { > + list_del(&block->link); > __drm_buddy_free(mm, block); > + } > return ERR_PTR(err); > } > -EXPORT_SYMBOL(drm_buddy_alloc_blocks); > - > -static inline bool overlaps(u64 s1, u64 e1, u64 s2, u64 e2) > -{ > - return s1 <= e2 && e1 >= s2; > -} > > -static inline bool contains(u64 s1, u64 e1, u64 s2, u64 e2) > -{ > - return s1 <= s2 && e1 >= e2; > -} > - > -/** > - * drm_buddy_alloc_range - allocate range > - * > - * @mm: DRM buddy manager to allocate from > - * @blocks: output list head to add allocated blocks > - * @start: start of the allowed range for this block > - * @size: size of the allocation > - * > - * Intended for pre-allocating portions of the address space, for example to > - * reserve a block for the initial framebuffer or similar, hence the expectation > - * here is that drm_buddy_alloc_blocks() is still the main vehicle for > - * allocations, so if that's not the case then the drm_mm range allocator is > - * probably a much better fit, and so you should probably go use that instead. > - * > - * Note that it's safe to chain together multiple alloc_ranges > - * with the same blocks list > - * > - * Returns: > - * 0 on success, error code on failure. > - */ > -int drm_buddy_alloc_range(struct drm_buddy *mm, > - struct list_head *blocks, > - u64 start, u64 size) > +static int __alloc_range(struct drm_buddy *mm, > + struct list_head *dfs, > + u64 start, u64 size, > + struct list_head *blocks) > { > struct drm_buddy_block *block; > struct drm_buddy_block *buddy; > - LIST_HEAD(allocated); > - LIST_HEAD(dfs); > u64 end; > int err; > - int i; > - > - if (size < mm->chunk_size) > - return -EINVAL; > - > - if (!IS_ALIGNED(size | start, mm->chunk_size)) > - return -EINVAL; > - > - if (range_overflows(start, size, mm->size)) > - return -EINVAL; > - > - for (i = 0; i < mm->n_roots; ++i) > - list_add_tail(&mm->roots[i]->tmp_link, &dfs); > > end = start + size - 1; > > @@ -399,7 +427,7 @@ int drm_buddy_alloc_range(struct drm_buddy *mm, > u64 block_start; > u64 block_end; > > - block = list_first_entry_or_null(&dfs, > + block = list_first_entry_or_null(dfs, > struct drm_buddy_block, > tmp_link); > if (!block) > @@ -426,7 +454,7 @@ int drm_buddy_alloc_range(struct drm_buddy *mm, > > mark_allocated(block); > mm->avail -= drm_buddy_block_size(mm, block); > - list_add_tail(&block->link, &allocated); > + list_add_tail(&block->link, blocks); > continue; > } > > @@ -436,11 +464,10 @@ int drm_buddy_alloc_range(struct drm_buddy *mm, > goto err_undo; > } > > - list_add(&block->right->tmp_link, &dfs); > - list_add(&block->left->tmp_link, &dfs); > + list_add(&block->right->tmp_link, dfs); > + list_add(&block->left->tmp_link, dfs); > } while (1); > > - list_splice_tail(&allocated, blocks); > return 0; > > err_undo: > @@ -452,14 +479,149 @@ int drm_buddy_alloc_range(struct drm_buddy *mm, > buddy = get_buddy(block); > if (buddy && > (drm_buddy_block_is_free(block) && > - drm_buddy_block_is_free(buddy))) > + drm_buddy_block_is_free(buddy))) { > + list_del(&block->link); > __drm_buddy_free(mm, block); > + } > + > +err_free: > + drm_buddy_free_list(mm, blocks); > + return err; > +} > + > +/** > + * __drm_buddy_alloc_range - actual range allocation > + * > + * @mm: DRM buddy manager to allocate from > + * @start: start of the allowed range for this block > + * @size: size of the allocation > + * @blocks: output list head to add allocated blocks > + * > + * Intended for pre-allocating portions of the address space, for example to > + * reserve a block for the initial framebuffer or similar > + * > + * Note that it's safe to chain together multiple alloc_ranges > + * with the same blocks list > + * > + * Returns: > + * 0 on success, error code on failure. > + */ > +static int __drm_buddy_alloc_range(struct drm_buddy *mm, > + u64 start, > + u64 size, > + struct list_head *blocks) > +{ > + LIST_HEAD(dfs); > + int i; > + > + for (i = 0; i < mm->n_roots; ++i) > + list_add_tail(&mm->roots[i]->tmp_link, &dfs); > + > + return __alloc_range(mm, &dfs, start, size, blocks); > +} > + > +/** > + * drm_buddy_alloc_blocks - allocate power-of-two blocks > + * > + * @mm: DRM buddy manager to allocate from > + * @start: start of the allowed range for this block > + * @end: end of the allowed range for this block > + * @size: size of the allocation > + * @min_page_size: alignment of the allocation > + * @blocks: output list head to add allocated blocks > + * @flags: DRM_BUDDY_*_ALLOCATION flags > + * > + * alloc_range_bias() called on range limitations, which traverses > + * the tree and returns the desired block. > + * > + * alloc_from_freelist() called when *no* range restrictions > + * are enforced, which picks the block from the freelist. > + * > + * blocks are allocated in order, the order value here translates to: > + * > + * 0 = 2^0 * mm->chunk_size > + * 1 = 2^1 * mm->chunk_size > + * 2 = 2^2 * mm->chunk_size > + * > + * Returns: > + * 0 on success, error code on failure. > + */ > +int drm_buddy_alloc_blocks(struct drm_buddy *mm, > + u64 start, u64 end, u64 size, > + u64 min_page_size, > + struct list_head *blocks, > + unsigned long flags) > +{ > + struct drm_buddy_block *block = NULL; > + unsigned int min_order, order; > + unsigned long pages; > + LIST_HEAD(allocated); > + int err; > + > + if (size < mm->chunk_size) > + return -EINVAL; > + > + if (min_page_size < mm->chunk_size) > + return -EINVAL; > + > + if (!is_power_of_2(min_page_size)) > + return -EINVAL; > + > + if (!IS_ALIGNED(start | end | size, mm->chunk_size)) > + return -EINVAL; > + > + if (check_range_overflow(start, end, size, mm->size)) > + return -EINVAL; > + > + /* Actual range allocation */ > + if (start + size == end) > + return __drm_buddy_alloc_range(mm, start, size, blocks); > + > + pages = size >> ilog2(mm->chunk_size); > + order = fls(pages) - 1; > + min_order = ilog2(min_page_size) - ilog2(mm->chunk_size); > + > + do { > + order = min(order, (unsigned int)fls(pages) - 1); > + BUG_ON(order > mm->max_order); > + BUG_ON(order < min_order); > + > + do { > + if (flags & DRM_BUDDY_RANGE_ALLOCATION) > + /* Allocate traversing within the range */ > + block = alloc_range_bias(mm, start, end, order); > + else > + /* Allocate from freelist */ > + block = alloc_from_freelist(mm, order, flags); > + > + if (!IS_ERR(block)) > + break; > + > + if (order-- == min_order) { > + err = -ENOSPC; > + goto err_free; > + } > + } while (1); > + > + mark_allocated(block); > + mm->avail -= drm_buddy_block_size(mm, block); > + kmemleak_update_trace(block); > + list_add_tail(&block->link, &allocated); > + > + pages -= BIT(order); > + > + if (!pages) > + break; > + } while (1); > + > + list_splice_tail(&allocated, blocks); > + return 0; > > err_free: > drm_buddy_free_list(mm, &allocated); > return err; > } > -EXPORT_SYMBOL(drm_buddy_alloc_range); > +EXPORT_SYMBOL(drm_buddy_alloc_blocks); > > /** > * drm_buddy_block_print - print block information > diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c > index 6ba314f9836a..1411f4cf1f21 100644 > --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c > +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c > @@ -36,13 +36,14 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, > struct i915_ttm_buddy_manager *bman = to_buddy_manager(man); > struct i915_ttm_buddy_resource *bman_res; > struct drm_buddy *mm = &bman->mm; > - unsigned long n_pages; > - unsigned int min_order; > + unsigned long n_pages, lpfn; > u64 min_page_size; > u64 size; > int err; > > - GEM_BUG_ON(place->fpfn || place->lpfn); > + lpfn = place->lpfn; > + if (!lpfn) > + lpfn = man->size; > > bman_res = kzalloc(sizeof(*bman_res), GFP_KERNEL); > if (!bman_res) > @@ -52,6 +53,9 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, > INIT_LIST_HEAD(&bman_res->blocks); > bman_res->mm = mm; > > + if (place->fpfn || lpfn != man->size) > + bman_res->flags |= DRM_BUDDY_RANGE_ALLOCATION; > + > GEM_BUG_ON(!bman_res->base.num_pages); > size = bman_res->base.num_pages << PAGE_SHIFT; > > @@ -60,10 +64,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, > min_page_size = bo->page_alignment << PAGE_SHIFT; > > GEM_BUG_ON(min_page_size < mm->chunk_size); > - min_order = ilog2(min_page_size) - ilog2(mm->chunk_size); > + > if (place->flags & TTM_PL_FLAG_CONTIGUOUS) { > + unsigned long pages; > + > size = roundup_pow_of_two(size); > - min_order = ilog2(size) - ilog2(mm->chunk_size); > + min_page_size = size; > + > + pages = size >> ilog2(mm->chunk_size); > + if (pages > lpfn) > + lpfn = pages; > } > > if (size > mm->size) { > @@ -73,34 +83,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, > > n_pages = size >> ilog2(mm->chunk_size); > > - do { > - struct drm_buddy_block *block; > - unsigned int order; > - > - order = fls(n_pages) - 1; > - GEM_BUG_ON(order > mm->max_order); > - GEM_BUG_ON(order < min_order); > - > - do { > - mutex_lock(&bman->lock); > - block = drm_buddy_alloc_blocks(mm, order); > - mutex_unlock(&bman->lock); > - if (!IS_ERR(block)) > - break; > - > - if (order-- == min_order) { > - err = -ENOSPC; > - goto err_free_blocks; > - } > - } while (1); > - > - n_pages -= BIT(order); > - > - list_add_tail(&block->link, &bman_res->blocks); > - > - if (!n_pages) > - break; > - } while (1); > + mutex_lock(&bman->lock); > + err = drm_buddy_alloc_blocks(mm, (u64)place->fpfn << PAGE_SHIFT, > + (u64)lpfn << PAGE_SHIFT, > + (u64)n_pages << PAGE_SHIFT, > + min_page_size, > + &bman_res->blocks, > + bman_res->flags); > + mutex_unlock(&bman->lock); > + if (unlikely(err)) > + goto err_free_blocks; > > *res = &bman_res->base; > return 0; > @@ -266,10 +258,17 @@ int i915_ttm_buddy_man_reserve(struct ttm_resource_manager *man, > { > struct i915_ttm_buddy_manager *bman = to_buddy_manager(man); > struct drm_buddy *mm = &bman->mm; > + unsigned long flags = 0; > int ret; > > + flags |= DRM_BUDDY_RANGE_ALLOCATION; > + > mutex_lock(&bman->lock); > - ret = drm_buddy_alloc_range(mm, &bman->reserved, start, size); > + ret = drm_buddy_alloc_blocks(mm, start, > + start + size, > + size, mm->chunk_size, > + &bman->reserved, > + flags); > mutex_unlock(&bman->lock); > > return ret; > diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h > index 312077941411..72c90b432e87 100644 > --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h > +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h > @@ -20,6 +20,7 @@ struct drm_buddy; > * > * @base: struct ttm_resource base class we extend > * @blocks: the list of struct i915_buddy_block for this resource/allocation > + * @flags: DRM_BUDDY_*_ALLOCATION flags > * @mm: the struct i915_buddy_mm for this resource > * > * Extends the struct ttm_resource to manage an address space allocation with > @@ -28,6 +29,7 @@ struct drm_buddy; > struct i915_ttm_buddy_resource { > struct ttm_resource base; > struct list_head blocks; > + unsigned long flags; > struct drm_buddy *mm; > }; > > diff --git a/include/drm/drm_buddy.h b/include/drm/drm_buddy.h > index f524db152413..865664b90a8a 100644 > --- a/include/drm/drm_buddy.h > +++ b/include/drm/drm_buddy.h > @@ -13,15 +13,22 @@ > > #include <drm/drm_print.h> > > -#define range_overflows(start, size, max) ({ \ > +#define check_range_overflow(start, end, size, max) ({ \ Random drive-by comment, why the rename? The old one is understandable, it's a bool, while "check", to me, implies it might *do* something in case of overflow. > typeof(start) start__ = (start); \ > + typeof(end) end__ = (end);\ > typeof(size) size__ = (size); \ > typeof(max) max__ = (max); \ > (void)(&start__ == &size__); \ > (void)(&start__ == &max__); \ > - start__ >= max__ || size__ > max__ - start__; \ > + (void)(&start__ == &end__); \ > + (void)(&end__ == &size__); \ > + (void)(&end__ == &max__); \ > + start__ >= max__ || end__ > max__ || \ > + size__ > end__ - start__; \ > }) > > +#define DRM_BUDDY_RANGE_ALLOCATION (1 << 0) > + > struct drm_buddy_block { > #define DRM_BUDDY_HEADER_OFFSET GENMASK_ULL(63, 12) > #define DRM_BUDDY_HEADER_STATE GENMASK_ULL(11, 10) > @@ -131,12 +138,11 @@ int drm_buddy_init(struct drm_buddy *mm, u64 size, u64 chunk_size); > > void drm_buddy_fini(struct drm_buddy *mm); > > -struct drm_buddy_block * > -drm_buddy_alloc_blocks(struct drm_buddy *mm, unsigned int order); > - > -int drm_buddy_alloc_range(struct drm_buddy *mm, > - struct list_head *blocks, > - u64 start, u64 size); > +int drm_buddy_alloc_blocks(struct drm_buddy *mm, > + u64 start, u64 end, u64 size, > + u64 min_page_size, > + struct list_head *blocks, > + unsigned long flags); > > void drm_buddy_free_block(struct drm_buddy *mm, struct drm_buddy_block *block);
diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c index d60878bc9c20..954e31962c74 100644 --- a/drivers/gpu/drm/drm_buddy.c +++ b/drivers/gpu/drm/drm_buddy.c @@ -282,23 +282,99 @@ void drm_buddy_free_list(struct drm_buddy *mm, struct list_head *objects) } EXPORT_SYMBOL(drm_buddy_free_list); -/** - * drm_buddy_alloc_blocks - allocate power-of-two blocks - * - * @mm: DRM buddy manager to allocate from - * @order: size of the allocation - * - * The order value here translates to: - * - * 0 = 2^0 * mm->chunk_size - * 1 = 2^1 * mm->chunk_size - * 2 = 2^2 * mm->chunk_size - * - * Returns: - * allocated ptr to the &drm_buddy_block on success - */ -struct drm_buddy_block * -drm_buddy_alloc_blocks(struct drm_buddy *mm, unsigned int order) +static inline bool overlaps(u64 s1, u64 e1, u64 s2, u64 e2) +{ + return s1 <= e2 && e1 >= s2; +} + +static inline bool contains(u64 s1, u64 e1, u64 s2, u64 e2) +{ + return s1 <= s2 && e1 >= e2; +} + +static struct drm_buddy_block * +alloc_range_bias(struct drm_buddy *mm, + u64 start, u64 end, + unsigned int order) +{ + struct drm_buddy_block *block; + struct drm_buddy_block *buddy; + LIST_HEAD(dfs); + int err; + int i; + + end = end - 1; + + for (i = 0; i < mm->n_roots; ++i) + list_add_tail(&mm->roots[i]->tmp_link, &dfs); + + do { + u64 block_start; + u64 block_end; + + block = list_first_entry_or_null(&dfs, + struct drm_buddy_block, + tmp_link); + if (!block) + break; + + list_del(&block->tmp_link); + + if (drm_buddy_block_order(block) < order) + continue; + + block_start = drm_buddy_block_offset(block); + block_end = block_start + drm_buddy_block_size(mm, block) - 1; + + if (!overlaps(start, end, block_start, block_end)) + continue; + + if (drm_buddy_block_is_allocated(block)) + continue; + + if (contains(start, end, block_start, block_end) && + order == drm_buddy_block_order(block)) { + /* + * Find the free block within the range. + */ + if (drm_buddy_block_is_free(block)) + return block; + + continue; + } + + if (!drm_buddy_block_is_split(block)) { + err = split_block(mm, block); + if (unlikely(err)) + goto err_undo; + } + + list_add(&block->right->tmp_link, &dfs); + list_add(&block->left->tmp_link, &dfs); + } while (1); + + return ERR_PTR(-ENOSPC); + +err_undo: + /* + * We really don't want to leave around a bunch of split blocks, since + * bigger is better, so make sure we merge everything back before we + * free the allocated blocks. + */ + buddy = get_buddy(block); + if (buddy && + (drm_buddy_block_is_free(block) && + drm_buddy_block_is_free(buddy))) { + list_del(&block->link); + __drm_buddy_free(mm, block); + } + return ERR_PTR(err); +} + +static struct drm_buddy_block * +alloc_from_freelist(struct drm_buddy *mm, + unsigned int order, + unsigned long flags) { struct drm_buddy_block *block = NULL; unsigned int i; @@ -320,78 +396,30 @@ drm_buddy_alloc_blocks(struct drm_buddy *mm, unsigned int order) while (i != order) { err = split_block(mm, block); if (unlikely(err)) - goto out_free; + goto err_undo; - /* Go low */ - block = block->left; + block = block->right; i--; } - - mark_allocated(block); - mm->avail -= drm_buddy_block_size(mm, block); - kmemleak_update_trace(block); return block; -out_free: - if (i != order) +err_undo: + if (i != order) { + list_del(&block->link); __drm_buddy_free(mm, block); + } return ERR_PTR(err); } -EXPORT_SYMBOL(drm_buddy_alloc_blocks); - -static inline bool overlaps(u64 s1, u64 e1, u64 s2, u64 e2) -{ - return s1 <= e2 && e1 >= s2; -} -static inline bool contains(u64 s1, u64 e1, u64 s2, u64 e2) -{ - return s1 <= s2 && e1 >= e2; -} - -/** - * drm_buddy_alloc_range - allocate range - * - * @mm: DRM buddy manager to allocate from - * @blocks: output list head to add allocated blocks - * @start: start of the allowed range for this block - * @size: size of the allocation - * - * Intended for pre-allocating portions of the address space, for example to - * reserve a block for the initial framebuffer or similar, hence the expectation - * here is that drm_buddy_alloc_blocks() is still the main vehicle for - * allocations, so if that's not the case then the drm_mm range allocator is - * probably a much better fit, and so you should probably go use that instead. - * - * Note that it's safe to chain together multiple alloc_ranges - * with the same blocks list - * - * Returns: - * 0 on success, error code on failure. - */ -int drm_buddy_alloc_range(struct drm_buddy *mm, - struct list_head *blocks, - u64 start, u64 size) +static int __alloc_range(struct drm_buddy *mm, + struct list_head *dfs, + u64 start, u64 size, + struct list_head *blocks) { struct drm_buddy_block *block; struct drm_buddy_block *buddy; - LIST_HEAD(allocated); - LIST_HEAD(dfs); u64 end; int err; - int i; - - if (size < mm->chunk_size) - return -EINVAL; - - if (!IS_ALIGNED(size | start, mm->chunk_size)) - return -EINVAL; - - if (range_overflows(start, size, mm->size)) - return -EINVAL; - - for (i = 0; i < mm->n_roots; ++i) - list_add_tail(&mm->roots[i]->tmp_link, &dfs); end = start + size - 1; @@ -399,7 +427,7 @@ int drm_buddy_alloc_range(struct drm_buddy *mm, u64 block_start; u64 block_end; - block = list_first_entry_or_null(&dfs, + block = list_first_entry_or_null(dfs, struct drm_buddy_block, tmp_link); if (!block) @@ -426,7 +454,7 @@ int drm_buddy_alloc_range(struct drm_buddy *mm, mark_allocated(block); mm->avail -= drm_buddy_block_size(mm, block); - list_add_tail(&block->link, &allocated); + list_add_tail(&block->link, blocks); continue; } @@ -436,11 +464,10 @@ int drm_buddy_alloc_range(struct drm_buddy *mm, goto err_undo; } - list_add(&block->right->tmp_link, &dfs); - list_add(&block->left->tmp_link, &dfs); + list_add(&block->right->tmp_link, dfs); + list_add(&block->left->tmp_link, dfs); } while (1); - list_splice_tail(&allocated, blocks); return 0; err_undo: @@ -452,14 +479,149 @@ int drm_buddy_alloc_range(struct drm_buddy *mm, buddy = get_buddy(block); if (buddy && (drm_buddy_block_is_free(block) && - drm_buddy_block_is_free(buddy))) + drm_buddy_block_is_free(buddy))) { + list_del(&block->link); __drm_buddy_free(mm, block); + } + +err_free: + drm_buddy_free_list(mm, blocks); + return err; +} + +/** + * __drm_buddy_alloc_range - actual range allocation + * + * @mm: DRM buddy manager to allocate from + * @start: start of the allowed range for this block + * @size: size of the allocation + * @blocks: output list head to add allocated blocks + * + * Intended for pre-allocating portions of the address space, for example to + * reserve a block for the initial framebuffer or similar + * + * Note that it's safe to chain together multiple alloc_ranges + * with the same blocks list + * + * Returns: + * 0 on success, error code on failure. + */ +static int __drm_buddy_alloc_range(struct drm_buddy *mm, + u64 start, + u64 size, + struct list_head *blocks) +{ + LIST_HEAD(dfs); + int i; + + for (i = 0; i < mm->n_roots; ++i) + list_add_tail(&mm->roots[i]->tmp_link, &dfs); + + return __alloc_range(mm, &dfs, start, size, blocks); +} + +/** + * drm_buddy_alloc_blocks - allocate power-of-two blocks + * + * @mm: DRM buddy manager to allocate from + * @start: start of the allowed range for this block + * @end: end of the allowed range for this block + * @size: size of the allocation + * @min_page_size: alignment of the allocation + * @blocks: output list head to add allocated blocks + * @flags: DRM_BUDDY_*_ALLOCATION flags + * + * alloc_range_bias() called on range limitations, which traverses + * the tree and returns the desired block. + * + * alloc_from_freelist() called when *no* range restrictions + * are enforced, which picks the block from the freelist. + * + * blocks are allocated in order, the order value here translates to: + * + * 0 = 2^0 * mm->chunk_size + * 1 = 2^1 * mm->chunk_size + * 2 = 2^2 * mm->chunk_size + * + * Returns: + * 0 on success, error code on failure. + */ +int drm_buddy_alloc_blocks(struct drm_buddy *mm, + u64 start, u64 end, u64 size, + u64 min_page_size, + struct list_head *blocks, + unsigned long flags) +{ + struct drm_buddy_block *block = NULL; + unsigned int min_order, order; + unsigned long pages; + LIST_HEAD(allocated); + int err; + + if (size < mm->chunk_size) + return -EINVAL; + + if (min_page_size < mm->chunk_size) + return -EINVAL; + + if (!is_power_of_2(min_page_size)) + return -EINVAL; + + if (!IS_ALIGNED(start | end | size, mm->chunk_size)) + return -EINVAL; + + if (check_range_overflow(start, end, size, mm->size)) + return -EINVAL; + + /* Actual range allocation */ + if (start + size == end) + return __drm_buddy_alloc_range(mm, start, size, blocks); + + pages = size >> ilog2(mm->chunk_size); + order = fls(pages) - 1; + min_order = ilog2(min_page_size) - ilog2(mm->chunk_size); + + do { + order = min(order, (unsigned int)fls(pages) - 1); + BUG_ON(order > mm->max_order); + BUG_ON(order < min_order); + + do { + if (flags & DRM_BUDDY_RANGE_ALLOCATION) + /* Allocate traversing within the range */ + block = alloc_range_bias(mm, start, end, order); + else + /* Allocate from freelist */ + block = alloc_from_freelist(mm, order, flags); + + if (!IS_ERR(block)) + break; + + if (order-- == min_order) { + err = -ENOSPC; + goto err_free; + } + } while (1); + + mark_allocated(block); + mm->avail -= drm_buddy_block_size(mm, block); + kmemleak_update_trace(block); + list_add_tail(&block->link, &allocated); + + pages -= BIT(order); + + if (!pages) + break; + } while (1); + + list_splice_tail(&allocated, blocks); + return 0; err_free: drm_buddy_free_list(mm, &allocated); return err; } -EXPORT_SYMBOL(drm_buddy_alloc_range); +EXPORT_SYMBOL(drm_buddy_alloc_blocks); /** * drm_buddy_block_print - print block information diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c index 6ba314f9836a..1411f4cf1f21 100644 --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c @@ -36,13 +36,14 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, struct i915_ttm_buddy_manager *bman = to_buddy_manager(man); struct i915_ttm_buddy_resource *bman_res; struct drm_buddy *mm = &bman->mm; - unsigned long n_pages; - unsigned int min_order; + unsigned long n_pages, lpfn; u64 min_page_size; u64 size; int err; - GEM_BUG_ON(place->fpfn || place->lpfn); + lpfn = place->lpfn; + if (!lpfn) + lpfn = man->size; bman_res = kzalloc(sizeof(*bman_res), GFP_KERNEL); if (!bman_res) @@ -52,6 +53,9 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, INIT_LIST_HEAD(&bman_res->blocks); bman_res->mm = mm; + if (place->fpfn || lpfn != man->size) + bman_res->flags |= DRM_BUDDY_RANGE_ALLOCATION; + GEM_BUG_ON(!bman_res->base.num_pages); size = bman_res->base.num_pages << PAGE_SHIFT; @@ -60,10 +64,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, min_page_size = bo->page_alignment << PAGE_SHIFT; GEM_BUG_ON(min_page_size < mm->chunk_size); - min_order = ilog2(min_page_size) - ilog2(mm->chunk_size); + if (place->flags & TTM_PL_FLAG_CONTIGUOUS) { + unsigned long pages; + size = roundup_pow_of_two(size); - min_order = ilog2(size) - ilog2(mm->chunk_size); + min_page_size = size; + + pages = size >> ilog2(mm->chunk_size); + if (pages > lpfn) + lpfn = pages; } if (size > mm->size) { @@ -73,34 +83,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, n_pages = size >> ilog2(mm->chunk_size); - do { - struct drm_buddy_block *block; - unsigned int order; - - order = fls(n_pages) - 1; - GEM_BUG_ON(order > mm->max_order); - GEM_BUG_ON(order < min_order); - - do { - mutex_lock(&bman->lock); - block = drm_buddy_alloc_blocks(mm, order); - mutex_unlock(&bman->lock); - if (!IS_ERR(block)) - break; - - if (order-- == min_order) { - err = -ENOSPC; - goto err_free_blocks; - } - } while (1); - - n_pages -= BIT(order); - - list_add_tail(&block->link, &bman_res->blocks); - - if (!n_pages) - break; - } while (1); + mutex_lock(&bman->lock); + err = drm_buddy_alloc_blocks(mm, (u64)place->fpfn << PAGE_SHIFT, + (u64)lpfn << PAGE_SHIFT, + (u64)n_pages << PAGE_SHIFT, + min_page_size, + &bman_res->blocks, + bman_res->flags); + mutex_unlock(&bman->lock); + if (unlikely(err)) + goto err_free_blocks; *res = &bman_res->base; return 0; @@ -266,10 +258,17 @@ int i915_ttm_buddy_man_reserve(struct ttm_resource_manager *man, { struct i915_ttm_buddy_manager *bman = to_buddy_manager(man); struct drm_buddy *mm = &bman->mm; + unsigned long flags = 0; int ret; + flags |= DRM_BUDDY_RANGE_ALLOCATION; + mutex_lock(&bman->lock); - ret = drm_buddy_alloc_range(mm, &bman->reserved, start, size); + ret = drm_buddy_alloc_blocks(mm, start, + start + size, + size, mm->chunk_size, + &bman->reserved, + flags); mutex_unlock(&bman->lock); return ret; diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h index 312077941411..72c90b432e87 100644 --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h @@ -20,6 +20,7 @@ struct drm_buddy; * * @base: struct ttm_resource base class we extend * @blocks: the list of struct i915_buddy_block for this resource/allocation + * @flags: DRM_BUDDY_*_ALLOCATION flags * @mm: the struct i915_buddy_mm for this resource * * Extends the struct ttm_resource to manage an address space allocation with @@ -28,6 +29,7 @@ struct drm_buddy; struct i915_ttm_buddy_resource { struct ttm_resource base; struct list_head blocks; + unsigned long flags; struct drm_buddy *mm; }; diff --git a/include/drm/drm_buddy.h b/include/drm/drm_buddy.h index f524db152413..865664b90a8a 100644 --- a/include/drm/drm_buddy.h +++ b/include/drm/drm_buddy.h @@ -13,15 +13,22 @@ #include <drm/drm_print.h> -#define range_overflows(start, size, max) ({ \ +#define check_range_overflow(start, end, size, max) ({ \ typeof(start) start__ = (start); \ + typeof(end) end__ = (end);\ typeof(size) size__ = (size); \ typeof(max) max__ = (max); \ (void)(&start__ == &size__); \ (void)(&start__ == &max__); \ - start__ >= max__ || size__ > max__ - start__; \ + (void)(&start__ == &end__); \ + (void)(&end__ == &size__); \ + (void)(&end__ == &max__); \ + start__ >= max__ || end__ > max__ || \ + size__ > end__ - start__; \ }) +#define DRM_BUDDY_RANGE_ALLOCATION (1 << 0) + struct drm_buddy_block { #define DRM_BUDDY_HEADER_OFFSET GENMASK_ULL(63, 12) #define DRM_BUDDY_HEADER_STATE GENMASK_ULL(11, 10) @@ -131,12 +138,11 @@ int drm_buddy_init(struct drm_buddy *mm, u64 size, u64 chunk_size); void drm_buddy_fini(struct drm_buddy *mm); -struct drm_buddy_block * -drm_buddy_alloc_blocks(struct drm_buddy *mm, unsigned int order); - -int drm_buddy_alloc_range(struct drm_buddy *mm, - struct list_head *blocks, - u64 start, u64 size); +int drm_buddy_alloc_blocks(struct drm_buddy *mm, + u64 start, u64 end, u64 size, + u64 min_page_size, + struct list_head *blocks, + unsigned long flags); void drm_buddy_free_block(struct drm_buddy *mm, struct drm_buddy_block *block);