mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 09:19:51 +00:00
![Chris Wilson](/assets/img/avatar_default.png)
Introduce the concept of padding the i915_vma with guard pages before and after. The major consequence is that all ordinary uses of i915_vma must use i915_vma_offset/i915_vma_size and not i915_vma.node.start/size directly, as the drm_mm_node will include the guard pages that surround our object. The biggest connundrum is how exactly to mix requesting a fixed address with guard pages, particularly through the existing uABI. The user does not know about guard pages, so such must be transparent to the user, and so the execobj.offset must be that of the object itself excluding the guard. So a PIN_OFFSET_FIXED must then be exclusive of the guard pages. The caveat is that some placements will be impossible with guard pages, as wrap arounds need to be avoided, and the vma itself will require a larger node. We must not report EINVAL but ENOSPC as these are unavailable locations within the GTT rather than conflicting user requirements. In the next patch, we start using guard pages for scanout objects. While these are limited to GGTT vma, on a few platforms these vma (or at least an alias of the vma) is shared with userspace, so we may leak the existence of such guards if we are not careful to ensure that the execobj.offset is transparent and excludes the guards. (On such platforms like ivb, without full-ppgtt, userspace has to use relocations so the presence of more untouchable regions within its GTT such be of no further issue.) Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@intel.com> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221201203912.346110-1-andi.shyti@linux.intel.com
251 lines
7.9 KiB
C
251 lines
7.9 KiB
C
/* SPDX-License-Identifier: MIT */
|
|
/*
|
|
* Copyright © 2021 Intel Corporation
|
|
*/
|
|
|
|
#ifndef __I915_VMA_RESOURCE_H__
|
|
#define __I915_VMA_RESOURCE_H__
|
|
|
|
#include <linux/dma-fence.h>
|
|
#include <linux/refcount.h>
|
|
|
|
#include "i915_gem.h"
|
|
#include "i915_scatterlist.h"
|
|
#include "i915_sw_fence.h"
|
|
#include "intel_runtime_pm.h"
|
|
|
|
struct intel_memory_region;
|
|
|
|
struct i915_page_sizes {
|
|
/**
|
|
* The sg mask of the pages sg_table. i.e the mask of
|
|
* the lengths for each sg entry.
|
|
*/
|
|
unsigned int phys;
|
|
|
|
/**
|
|
* The gtt page sizes we are allowed to use given the
|
|
* sg mask and the supported page sizes. This will
|
|
* express the smallest unit we can use for the whole
|
|
* object, as well as the larger sizes we may be able
|
|
* to use opportunistically.
|
|
*/
|
|
unsigned int sg;
|
|
};
|
|
|
|
/**
|
|
* struct i915_vma_resource - Snapshotted unbind information.
|
|
* @unbind_fence: Fence to mark unbinding complete. Note that this fence
|
|
* is not considered published until unbind is scheduled, and as such it
|
|
* is illegal to access this fence before scheduled unbind other than
|
|
* for refcounting.
|
|
* @lock: The @unbind_fence lock.
|
|
* @hold_count: Number of holders blocking the fence from finishing.
|
|
* The vma itself is keeping a hold, which is released when unbind
|
|
* is scheduled.
|
|
* @work: Work struct for deferred unbind work.
|
|
* @chain: Pointer to struct i915_sw_fence used to await dependencies.
|
|
* @rb: Rb node for the vm's pending unbind interval tree.
|
|
* @__subtree_last: Interval tree private member.
|
|
* @vm: non-refcounted pointer to the vm. This is for internal use only and
|
|
* this member is cleared after vm_resource unbind.
|
|
* @mr: The memory region of the object pointed to by the vma.
|
|
* @ops: Pointer to the backend i915_vma_ops.
|
|
* @private: Bind backend private info.
|
|
* @start: Offset into the address space of bind range start. Note that
|
|
* this is after any padding that might have been allocated.
|
|
* @node_size: Size of the allocated range manager node with padding
|
|
* subtracted.
|
|
* @vma_size: Bind size.
|
|
* @guard: The size of guard area preceding and trailing the bind.
|
|
* @page_sizes_gtt: Resulting page sizes from the bind operation.
|
|
* @bound_flags: Flags indicating binding status.
|
|
* @allocated: Backend private data. TODO: Should move into @private.
|
|
* @immediate_unbind: Unbind can be done immediately and doesn't need to be
|
|
* deferred to a work item awaiting unsignaled fences. This is a hack.
|
|
* (dma_fence_work uses a fence flag for this, but this seems slightly
|
|
* cleaner).
|
|
* @needs_wakeref: Whether a wakeref is needed during unbind. Since we can't
|
|
* take a wakeref in the dma-fence signalling critical path, it needs to be
|
|
* taken when the unbind is scheduled.
|
|
* @skip_pte_rewrite: During ggtt suspend and vm takedown pte rewriting
|
|
* needs to be skipped for unbind.
|
|
* @tlb: pointer for obj->mm.tlb, if async unbind. Otherwise, NULL
|
|
*
|
|
* The lifetime of a struct i915_vma_resource is from a binding request to
|
|
* the actual possible asynchronous unbind has completed.
|
|
*/
|
|
struct i915_vma_resource {
|
|
struct dma_fence unbind_fence;
|
|
/* See above for description of the lock. */
|
|
spinlock_t lock;
|
|
refcount_t hold_count;
|
|
struct work_struct work;
|
|
struct i915_sw_fence chain;
|
|
struct rb_node rb;
|
|
u64 __subtree_last;
|
|
struct i915_address_space *vm;
|
|
intel_wakeref_t wakeref;
|
|
|
|
/**
|
|
* struct i915_vma_bindinfo - Information needed for async bind
|
|
* only but that can be dropped after the bind has taken place.
|
|
* Consider making this a separate argument to the bind_vma
|
|
* op, coalescing with other arguments like vm, stash, cache_level
|
|
* and flags
|
|
* @pages: The pages sg-table.
|
|
* @page_sizes: Page sizes of the pages.
|
|
* @pages_rsgt: Refcounted sg-table when delayed object destruction
|
|
* is supported. May be NULL.
|
|
* @readonly: Whether the vma should be bound read-only.
|
|
* @lmem: Whether the vma points to lmem.
|
|
*/
|
|
struct i915_vma_bindinfo {
|
|
struct sg_table *pages;
|
|
struct i915_page_sizes page_sizes;
|
|
struct i915_refct_sgt *pages_rsgt;
|
|
bool readonly:1;
|
|
bool lmem:1;
|
|
} bi;
|
|
|
|
#if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
|
|
struct intel_memory_region *mr;
|
|
#endif
|
|
const struct i915_vma_ops *ops;
|
|
void *private;
|
|
u64 start;
|
|
u64 node_size;
|
|
u64 vma_size;
|
|
u32 guard;
|
|
u32 page_sizes_gtt;
|
|
|
|
u32 bound_flags;
|
|
bool allocated:1;
|
|
bool immediate_unbind:1;
|
|
bool needs_wakeref:1;
|
|
bool skip_pte_rewrite:1;
|
|
|
|
u32 *tlb;
|
|
};
|
|
|
|
bool i915_vma_resource_hold(struct i915_vma_resource *vma_res,
|
|
bool *lockdep_cookie);
|
|
|
|
void i915_vma_resource_unhold(struct i915_vma_resource *vma_res,
|
|
bool lockdep_cookie);
|
|
|
|
struct i915_vma_resource *i915_vma_resource_alloc(void);
|
|
|
|
void i915_vma_resource_free(struct i915_vma_resource *vma_res);
|
|
|
|
struct dma_fence *i915_vma_resource_unbind(struct i915_vma_resource *vma_res,
|
|
u32 *tlb);
|
|
|
|
void __i915_vma_resource_init(struct i915_vma_resource *vma_res);
|
|
|
|
/**
|
|
* i915_vma_resource_get - Take a reference on a vma resource
|
|
* @vma_res: The vma resource on which to take a reference.
|
|
*
|
|
* Return: The @vma_res pointer
|
|
*/
|
|
static inline struct i915_vma_resource
|
|
*i915_vma_resource_get(struct i915_vma_resource *vma_res)
|
|
{
|
|
dma_fence_get(&vma_res->unbind_fence);
|
|
return vma_res;
|
|
}
|
|
|
|
/**
|
|
* i915_vma_resource_put - Release a reference to a struct i915_vma_resource
|
|
* @vma_res: The resource
|
|
*/
|
|
static inline void i915_vma_resource_put(struct i915_vma_resource *vma_res)
|
|
{
|
|
dma_fence_put(&vma_res->unbind_fence);
|
|
}
|
|
|
|
/**
|
|
* i915_vma_resource_init - Initialize a vma resource.
|
|
* @vma_res: The vma resource to initialize
|
|
* @vm: Pointer to the vm.
|
|
* @pages: The pages sg-table.
|
|
* @page_sizes: Page sizes of the pages.
|
|
* @pages_rsgt: Pointer to a struct i915_refct_sgt of an object with
|
|
* delayed destruction.
|
|
* @readonly: Whether the vma should be bound read-only.
|
|
* @lmem: Whether the vma points to lmem.
|
|
* @mr: The memory region of the object the vma points to.
|
|
* @ops: The backend ops.
|
|
* @private: Bind backend private info.
|
|
* @start: Offset into the address space of bind range start after padding.
|
|
* @node_size: Size of the allocated range manager node minus padding.
|
|
* @size: Bind size.
|
|
* @guard: The size of the guard area preceding and trailing the bind.
|
|
*
|
|
* Initializes a vma resource allocated using i915_vma_resource_alloc().
|
|
* The reason for having separate allocate and initialize function is that
|
|
* initialization may need to be performed from under a lock where
|
|
* allocation is not allowed.
|
|
*/
|
|
static inline void i915_vma_resource_init(struct i915_vma_resource *vma_res,
|
|
struct i915_address_space *vm,
|
|
struct sg_table *pages,
|
|
const struct i915_page_sizes *page_sizes,
|
|
struct i915_refct_sgt *pages_rsgt,
|
|
bool readonly,
|
|
bool lmem,
|
|
struct intel_memory_region *mr,
|
|
const struct i915_vma_ops *ops,
|
|
void *private,
|
|
u64 start,
|
|
u64 node_size,
|
|
u64 size,
|
|
u32 guard)
|
|
{
|
|
__i915_vma_resource_init(vma_res);
|
|
vma_res->vm = vm;
|
|
vma_res->bi.pages = pages;
|
|
vma_res->bi.page_sizes = *page_sizes;
|
|
if (pages_rsgt)
|
|
vma_res->bi.pages_rsgt = i915_refct_sgt_get(pages_rsgt);
|
|
vma_res->bi.readonly = readonly;
|
|
vma_res->bi.lmem = lmem;
|
|
#if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
|
|
vma_res->mr = mr;
|
|
#endif
|
|
vma_res->ops = ops;
|
|
vma_res->private = private;
|
|
vma_res->start = start;
|
|
vma_res->node_size = node_size;
|
|
vma_res->vma_size = size;
|
|
vma_res->guard = guard;
|
|
}
|
|
|
|
static inline void i915_vma_resource_fini(struct i915_vma_resource *vma_res)
|
|
{
|
|
GEM_BUG_ON(refcount_read(&vma_res->hold_count) != 1);
|
|
if (vma_res->bi.pages_rsgt)
|
|
i915_refct_sgt_put(vma_res->bi.pages_rsgt);
|
|
i915_sw_fence_fini(&vma_res->chain);
|
|
}
|
|
|
|
int i915_vma_resource_bind_dep_sync(struct i915_address_space *vm,
|
|
u64 first,
|
|
u64 last,
|
|
bool intr);
|
|
|
|
int i915_vma_resource_bind_dep_await(struct i915_address_space *vm,
|
|
struct i915_sw_fence *sw_fence,
|
|
u64 first,
|
|
u64 last,
|
|
bool intr,
|
|
gfp_t gfp);
|
|
|
|
void i915_vma_resource_bind_dep_sync_all(struct i915_address_space *vm);
|
|
|
|
void i915_vma_resource_module_exit(void);
|
|
|
|
int i915_vma_resource_module_init(void);
|
|
|
|
#endif
|