[Intel-gfx] [PATCH 38/56] drm/i915/bdw: Dynamic page table allocations
Ben Widawsky
benjamin.widawsky at intel.com
Sat May 10 05:59:33 CEST 2014
This finishes off the dynamic page tables allocations, in the legacy 3
level style that already exists. Most everything has already been setup
to this point, the patch finishes off the enabling by setting the
appropriate function pointers.
Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
drivers/gpu/drm/i915/i915_gem_gtt.c | 261 +++++++++++++++++++++++++++++-------
1 file changed, 216 insertions(+), 45 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 82b98ea..66ed943 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -653,58 +653,160 @@ static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
gen8_ppgtt_free(ppgtt);
}
-static int gen8_ppgtt_alloc_pagetabs(struct i915_pagedir *pd,
+/**
+ * gen8_ppgtt_alloc_pagetabs() - Allocate page tables for VA range.
+ * @ppgtt: Master ppgtt structure.
+ * @pd: Page directory for this address range.
+ * @start: Starting virtual address to begin allocations.
+ * @length Size of the allocations.
+ * @new_pts: Bitmap set by function with new allocations. Likely used by the
+ * caller to free on error.
+ *
+ * Allocate the required number of page tables. Extremely similar to
+ * gen8_ppgtt_alloc_pagedirs(). The main difference is here we are limited by
+ * the page directory boundary (instead of the page directory pointer). That
+ * boundary is 1GB virtual. Therefore, unlike gen8_ppgtt_alloc_pagedirs(), it is
+ * possible, and likely that the caller will need to use multiple calls of this
+ * function to achieve the appropriate allocation.
+ *
+ * Return: 0 if success; negative error code otherwise.
+ */
+static int gen8_ppgtt_alloc_pagetabs(struct i915_hw_ppgtt *ppgtt,
+ struct i915_pagedir *pd,
uint64_t start,
uint64_t length,
- struct drm_device *dev)
+ unsigned long *new_pts)
{
struct i915_pagetab *unused;
uint64_t temp;
uint32_t pde;
gen8_for_each_pde(unused, pd, start, length, temp, pde) {
- BUG_ON(unused);
- pd->page_tables[pde] = alloc_pt_single(dev);
+ if (unused)
+ continue;
+
+ pd->page_tables[pde] = alloc_pt_single(ppgtt->base.dev);
+
if (IS_ERR(pd->page_tables[pde]))
goto unwind_out;
+
+ set_bit(pde, new_pts);
}
return 0;
unwind_out:
- while (pde--)
- free_pt_single(pd->page_tables[pde], dev);
+ for_each_set_bit(pde, new_pts, I915_PDES_PER_PD)
+ free_pt_single(pd->page_tables[pde], ppgtt->base.dev);
return -ENOMEM;
}
-/* bitmap of new pagedirs */
-static int gen8_ppgtt_alloc_pagedirs(struct i915_pagedirpo *pdp,
+/**
+ * gen8_ppgtt_alloc_pagedirs() - Allocate page directories for VA range.
+ * @ppgtt: Master ppgtt structure.
+ * @pdp: Page directory pointer for this address range.
+ * @start: Starting virtual address to begin allocations.
+ * @length Size of the allocations.
+ * @new_pds Bitmap set by function with new allocations. Likely used by the
+ * caller to free on error.
+ *
+ * Allocate the required number of page directories starting at the pde index of
+ * @start, and ending at the pde index @start + @length. This function will skip
+ * over already allocated page directories within the range, and only allocate
+ * new ones, setting the appropriate pointer within the pdp as well as the
+ * correct position in the bitmap @new_pds.
+ *
+ * The function will only allocate the pages within the range for a give page
+ * directory pointer. In other words, if @start + @length straddles a virtually
+ * addressed PDP boundary (512GB for 4k pages), there will be more allocations
+ * required by the caller, This is not currently possible, and the BUG in the
+ * code will prevent it.
+ *
+ * Return: 0 if success; negative error code otherwise.
+ */
+static int gen8_ppgtt_alloc_pagedirs(struct i915_hw_ppgtt *ppgtt,
+ struct i915_pagedirpo *pdp,
uint64_t start,
uint64_t length,
- struct drm_device *dev)
+ unsigned long *new_pds)
{
struct i915_pagedir *unused;
uint64_t temp;
uint32_t pdpe;
+ BUG_ON(!bitmap_empty(new_pds, GEN8_LEGACY_PDPES));
+
/* FIXME: PPGTT container_of won't work for 64b */
BUG_ON((start + length) > 0x800000000ULL);
gen8_for_each_pdpe(unused, pdp, start, length, temp, pdpe) {
- BUG_ON(unused);
- pdp->pagedirs[pdpe] = alloc_pd_single(dev);
+ struct i915_pagedir *pd;
+ if (unused)
+ continue;
- if (IS_ERR(pdp->pagedirs[pdpe]))
+ pd = alloc_pd_single(ppgtt->base.dev);
+ if (IS_ERR(pd))
goto unwind_out;
+
+ pdp->pagedirs[pdpe] = pd;
+ set_bit(pdpe, new_pds);
}
return 0;
unwind_out:
- while (pdpe--)
- free_pd_single(pdp->pagedirs[pdpe], dev);
+ for_each_set_bit(pdpe, new_pds, GEN8_LEGACY_PDPES)
+ free_pd_single(pdp->pagedirs[pdpe], ppgtt->base.dev);
+
+ return -ENOMEM;
+}
+
+void free_gen8_temp_bitmaps(unsigned long *new_pds,
+ unsigned long **new_pts)
+{
+ int i;
+ for (i = 0; i < GEN8_LEGACY_PDPES; i++)
+ kfree(new_pts[i]);
+ kfree(new_pts);
+ kfree(new_pds);
+}
+/* Fills in the page directory bitmap, ant the array of page tables bitmap. Both
+ * of these are based on the number of PDPEs in the system.
+ */
+int __must_check alloc_gen8_temp_bitmaps(unsigned long **new_pds,
+ unsigned long ***new_pts)
+{
+ int i;
+ unsigned long *pds = kcalloc(BITS_TO_LONGS(GEN8_LEGACY_PDPES),
+ sizeof(unsigned long),
+ GFP_KERNEL);
+
+ unsigned long **pts = kcalloc(I915_PDES_PER_PD,
+ sizeof(unsigned long *),
+ GFP_KERNEL);
+
+ if (!pts || !pds)
+ goto err_out;
+
+ for (i = 0; i < GEN8_LEGACY_PDPES; i++) {
+ pts[i] = kcalloc(BITS_TO_LONGS(I915_PDES_PER_PD),
+ sizeof(unsigned long), GFP_KERNEL);
+ if (!pts[i])
+ goto err_out;
+ }
+
+ *new_pds = pds;
+ *new_pts = (unsigned long **)pts;
+
+ return 0;
+
+err_out:
+ for (i = 0; i < GEN8_LEGACY_PDPES; i++)
+ kfree(pts[i]);
+ kfree(pds);
+ kfree(pts);
return -ENOMEM;
}
@@ -714,6 +816,7 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
{
struct i915_hw_ppgtt *ppgtt =
container_of(vm, struct i915_hw_ppgtt, base);
+ unsigned long *new_page_dirs, **new_page_tables;
struct i915_pagedir *pd;
const uint64_t orig_start = start;
const uint64_t orig_length = length;
@@ -721,22 +824,40 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
uint32_t pdpe;
int ret;
- /* Do the allocations first so we can easily bail out */
- ret = gen8_ppgtt_alloc_pagedirs(&ppgtt->pdp, start, length,
- ppgtt->base.dev);
+#ifdef CONFIG_32BIT
+ /* Disallow 64b address on 32b platforms. Nothing is wrong with doing
+ * this in hardware, but a lot of the drm code is not prepared to handle
+ * 64b offset on 32b platforms. */
+ if (start + length > 0x100000000ULL)
+ return -E2BIG;
+#endif
+
+ /* Wrap is never okay since we can only represent 48b, and we don't
+ * actually use the other side of the canonical address space.
+ */
+ if (WARN_ON(start + length < start))
+ return -ERANGE;
+
+ ret = alloc_gen8_temp_bitmaps(&new_page_dirs, &new_page_tables);
if (ret)
return ret;
+ /* Do the allocations first so we can easily bail out */
+ ret = gen8_ppgtt_alloc_pagedirs(ppgtt, &ppgtt->pdp, start, length,
+ new_page_dirs);
+ if (ret) {
+ free_gen8_temp_bitmaps(new_page_dirs, new_page_tables);
+ return ret;
+ }
+
gen8_for_each_pdpe(pd, &ppgtt->pdp, start, length, temp, pdpe) {
- ret = gen8_ppgtt_alloc_pagetabs(pd, start, length,
- ppgtt->base.dev);
+ bitmap_zero(new_page_tables[pdpe], I915_PDES_PER_PD);
+ ret = gen8_ppgtt_alloc_pagetabs(ppgtt, pd, start, length,
+ new_page_tables[pdpe]);
if (ret)
goto err_out;
}
- /* Now mark everything we've touched as used. This doesn't allow for
- * robust error checking, but it makes the code a hell of a lot simpler.
- */
start = orig_start;
length = orig_length;
@@ -745,19 +866,37 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
uint64_t pd_len = gen8_clamp_pd(start, length);
uint64_t pd_start = start;
uint32_t pde;
- gen8_for_each_pde(pt, &ppgtt->pd, pd_start, pd_len, temp, pde) {
- bitmap_set(pd->page_tables[pde]->used_ptes,
- gen8_pte_index(start),
- gen8_pte_count(start, length));
+
+ BUG_ON(!pd);
+
+ gen8_for_each_pde(pt, pd, pd_start, pd_len, temp, pde) {
+ BUG_ON(!pt);
+
+ bitmap_set(pt->used_ptes,
+ gen8_pte_index(pd_start),
+ gen8_pte_count(pd_start, pd_len));
+
set_bit(pde, pd->used_pdes);
}
+
set_bit(pdpe, ppgtt->pdp.used_pdpes);
+
+ gen8_map_pagetable_range(pd, start, length, ppgtt->base.dev);
}
+ free_gen8_temp_bitmaps(new_page_dirs, new_page_tables);
return 0;
err_out:
- gen8_teardown_va_range(vm, orig_start, start);
+ while (pdpe--) {
+ for_each_set_bit(temp, new_page_tables[pdpe], I915_PDES_PER_PD)
+ free_pt_single(pd->page_tables[temp], ppgtt->base.dev);
+ }
+
+ for_each_set_bit(pdpe, new_page_dirs, GEN8_LEGACY_PDPES)
+ free_pd_single(ppgtt->pdp.pagedirs[pdpe], ppgtt->base.dev);
+
+ free_gen8_temp_bitmaps(new_page_dirs, new_page_tables);
return ret;
}
@@ -768,38 +907,65 @@ err_out:
* space.
*
*/
-static int gen8_ppgtt_init(struct i915_hw_ppgtt *ppgtt, uint64_t size)
+static int gen8_ppgtt_init_common(struct i915_hw_ppgtt *ppgtt, uint64_t size)
{
- struct i915_pagedir *pd;
- uint64_t temp, start = 0;
- const uint64_t orig_length = size;
- uint32_t pdpe;
- int ret;
-
ppgtt->base.start = 0;
ppgtt->base.total = size;
- ppgtt->base.clear_range = gen8_ppgtt_clear_range;
- ppgtt->base.insert_entries = gen8_ppgtt_insert_entries;
ppgtt->base.cleanup = gen8_ppgtt_cleanup;
ppgtt->enable = gen8_ppgtt_enable;
ppgtt->switch_mm = gen8_mm_switch;
+ ppgtt->base.insert_entries = gen8_ppgtt_insert_entries;
ppgtt->scratch_pd = alloc_pt_scratch(ppgtt->base.dev);
if (IS_ERR(ppgtt->scratch_pd))
return PTR_ERR(ppgtt->scratch_pd);
+ return 0;
+}
+
+static int gen8_aliasing_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
+{
+ struct drm_device *dev = ppgtt->base.dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct i915_pagedir *pd;
+ uint64_t temp, start = 0, size = dev_priv->gtt.base.total;
+ uint32_t pdpe;
+ int ret;
+
+ ret = gen8_ppgtt_init_common(ppgtt, dev_priv->gtt.base.total);
+ if (ret)
+ return ret;
+
ret = gen8_alloc_va_range(&ppgtt->base, start, size);
if (ret) {
free_pt_scratch(ppgtt->scratch_pd, ppgtt->base.dev);
return ret;
}
- start = 0;
- size = orig_length;
-
gen8_for_each_pdpe(pd, &ppgtt->pdp, start, size, temp, pdpe)
gen8_map_pagetable_range(pd, start, size, ppgtt->base.dev);
+ ppgtt->base.allocate_va_range = NULL;
+ ppgtt->base.teardown_va_range = NULL;
+ ppgtt->base.clear_range = gen8_ppgtt_clear_range;
+
+ return 0;
+}
+
+static int gen8_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
+{
+ struct drm_device *dev = ppgtt->base.dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ int ret;
+
+ ret = gen8_ppgtt_init_common(ppgtt, dev_priv->gtt.base.total);
+ if (ret)
+ return ret;
+
+ ppgtt->base.allocate_va_range = gen8_alloc_va_range;
+ ppgtt->base.teardown_va_range = gen8_teardown_va_range;
+ ppgtt->base.clear_range = NULL;
+
return 0;
}
@@ -1454,8 +1620,10 @@ int i915_gem_init_ppgtt(struct drm_device *dev, struct i915_hw_ppgtt *ppgtt, boo
if (INTEL_INFO(dev)->gen < 8)
ret = gen6_ppgtt_init(ppgtt, aliasing);
+ else if (IS_GEN8(dev) && aliasing)
+ ret = gen8_aliasing_ppgtt_init(ppgtt);
else if (IS_GEN8(dev))
- ret = gen8_ppgtt_init(ppgtt, dev_priv->gtt.base.total);
+ ret = gen8_ppgtt_init(ppgtt);
else
BUG();
@@ -1464,7 +1632,8 @@ int i915_gem_init_ppgtt(struct drm_device *dev, struct i915_hw_ppgtt *ppgtt, boo
kref_init(&ppgtt->ref);
drm_mm_init(&ppgtt->base.mm, ppgtt->base.start, ppgtt->base.total);
- ppgtt->base.clear_range(&ppgtt->base, 0, ppgtt->base.total, true);
+ if (ppgtt->base.clear_range)
+ ppgtt->base.clear_range(&ppgtt->base, 0, ppgtt->base.total, true);
i915_init_vm(dev_priv, &ppgtt->base);
return 0;
@@ -1508,10 +1677,12 @@ ppgtt_bind_vma(struct i915_vma *vma,
static void ppgtt_unbind_vma(struct i915_vma *vma)
{
- vma->vm->clear_range(vma->vm,
- vma->node.start,
- vma->obj->base.size,
- true);
+ if (vma->vm->clear_range)
+ vma->vm->clear_range(vma->vm,
+ vma->node.start,
+ vma->obj->base.size,
+ true);
+
if (vma->vm->teardown_va_range) {
trace_i915_va_teardown(vma->vm,
vma->node.start, vma->node.size);
--
1.9.2
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