linux/drivers/gpu/drm/i915/i915_vma.h
Thomas Hellström c03d982670 drm/i915: Clarify vma lifetime
It's unclear what reference the initial vma kref reference refers to.
A vma can have multiple weak references, the object vma list,
the vm's bound list and the GT's closed_list, and the initial vma
reference can be put from lookups of all these lists.

With the current implementation this means
that any holder of yet another vma refcount (currently only
i915_gem_object_unbind()) needs to be holding two of either
*) An object refcount,
*) A vm open count
*) A vma open count

in order for us to not risk leaking a reference by having the
initial vma reference being put twice.

Address this by re-introducing i915_vma_destroy() which removes all
weak references of the vma and *then* puts the initial vma refcount.
This makes a strong vma reference hold on to the vma unconditionally.

Perhaps a better name would be i915_vma_revoke() or i915_vma_zombify(),
since other callers may still hold a refcount, but with the prospect of
being able to replace the vma refcount with the object lock in the near
future, let's stick with i915_vma_destroy().

Finally this commit fixes a race in that previously i915_vma_release() and
now i915_vma_destroy() could destroy a vma without taking the vm->mutex
after an advisory check that the vma mm_node was not allocated.
This would race with the ungrab_vma() function creating a trace similar
to the below one. This was fixed in one of the __i915_vma_put() callsites
in
commit bc1922e5d349 ("drm/i915: Fix a race between vma / object destruction and unbinding")
but although not seemingly triggered by CI, that
is not sufficient. This patch is needed to fix that properly.

[823.012188] Console: switching to colour dummy device 80x25
[823.012422] [IGT] gem_ppgtt: executing
[823.016667] [IGT] gem_ppgtt: starting subtest blt-vs-render-ctx0
[852.436465] stack segment: 0000 [#1] PREEMPT SMP NOPTI
[852.436480] CPU: 0 PID: 3200 Comm: gem_ppgtt Not tainted 5.16.0-CI-CI_DRM_11115+ #1
[852.436489] Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-P DDR5 RVP, BIOS ADLPFWI1.R00.2422.A00.2110131104 10/13/2021
[852.436499] RIP: 0010:ungrab_vma+0x9/0x80 [i915]
[852.436711] Code: ef e8 4b 85 cf e0 e8 36 a3 d6 e0 8b 83 f8 9c 00 00 85 c0 75 e1 5b 5d 41 5c 41 5d c3 e9 d6 fd 14 00 55 53 48 8b af c0 00 00 00 <8b> 45 00 85 c0 75 03 5b 5d c3 48 8b 85 a0 02 00 00 48 89 fb 48 8b
[852.436727] RSP: 0018:ffffc90006db7880 EFLAGS: 00010246
[852.436734] RAX: 0000000000000000 RBX: ffffc90006db7598 RCX: 0000000000000000
[852.436742] RDX: ffff88815349e898 RSI: ffff88815349e858 RDI: ffff88810a284140
[852.436748] RBP: 6b6b6b6b6b6b6b6b R08: ffff88815349e898 R09: ffff88815349e8e8
[852.436754] R10: 0000000000000001 R11: 0000000051ef1141 R12: ffff88810a284140
[852.436762] R13: 0000000000000000 R14: ffff88815349e868 R15: ffff88810a284458
[852.436770] FS:  00007f5c04b04e40(0000) GS:ffff88849f000000(0000) knlGS:0000000000000000
[852.436781] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[852.436788] CR2: 00007f5c04b38fe0 CR3: 000000010a6e8001 CR4: 0000000000770ef0
[852.436797] PKRU: 55555554
[852.436801] Call Trace:
[852.436806]  <TASK>
[852.436811]  i915_gem_evict_for_node+0x33c/0x3c0 [i915]
[852.437014]  i915_gem_gtt_reserve+0x106/0x130 [i915]
[852.437211]  i915_vma_pin_ww+0x8f4/0xb60 [i915]
[852.437412]  eb_validate_vmas+0x688/0x860 [i915]
[852.437596]  i915_gem_do_execbuffer+0xc0e/0x25b0 [i915]
[852.437770]  ? deactivate_slab+0x5f2/0x7d0
[852.437778]  ? _raw_spin_unlock_irqrestore+0x50/0x60
[852.437789]  ? i915_gem_execbuffer2_ioctl+0xc6/0x2c0 [i915]
[852.437944]  ? init_object+0x49/0x80
[852.437950]  ? __lock_acquire+0x5e6/0x2580
[852.437963]  i915_gem_execbuffer2_ioctl+0x116/0x2c0 [i915]
[852.438129]  ? i915_gem_do_execbuffer+0x25b0/0x25b0 [i915]
[852.438300]  drm_ioctl_kernel+0xac/0x140
[852.438310]  drm_ioctl+0x201/0x3d0
[852.438316]  ? i915_gem_do_execbuffer+0x25b0/0x25b0 [i915]
[852.438490]  __x64_sys_ioctl+0x6a/0xa0
[852.438498]  do_syscall_64+0x37/0xb0
[852.438507]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[852.438515] RIP: 0033:0x7f5c0415b317
[852.438523] Code: b3 66 90 48 8b 05 71 4b 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 41 4b 2d 00 f7 d8 64 89 01 48
[852.438542] RSP: 002b:00007ffd765039a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[852.438553] RAX: ffffffffffffffda RBX: 000055e4d7829dd0 RCX: 00007f5c0415b317
[852.438562] RDX: 00007ffd76503a00 RSI: 00000000c0406469 RDI: 0000000000000017
[852.438571] RBP: 00007ffd76503a00 R08: 0000000000000000 R09: 0000000000000081
[852.438579] R10: 00000000ffffff7f R11: 0000000000000246 R12: 00000000c0406469
[852.438587] R13: 0000000000000017 R14: 00007ffd76503a00 R15: 0000000000000000
[852.438598]  </TASK>
[852.438602] Modules linked in: snd_hda_codec_hdmi i915 mei_hdcp x86_pkg_temp_thermal snd_hda_intel snd_intel_dspcfg drm_buddy coretemp crct10dif_pclmul crc32_pclmul snd_hda_codec ttm ghash_clmulni_intel snd_hwdep snd_hda_core e1000e drm_dp_helper ptp snd_pcm mei_me drm_kms_helper pps_core mei syscopyarea sysfillrect sysimgblt fb_sys_fops prime_numbers intel_lpss_pci smsc75xx usbnet mii
[852.440310] ---[ end trace e52cdd2fe4fd911c ]---

v2: Fix typos in the commit message.

Fixes: 7e00897be8bf ("drm/i915: Add object locking to i915_gem_evict_for_node and i915_gem_evict_something, v2.")
Fixes: bc1922e5d349 ("drm/i915: Fix a race between vma / object destruction and unbinding")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220222133209.587978-1-thomas.hellstrom@linux.intel.com
2022-02-28 15:04:53 +01:00

459 lines
13 KiB
C

/*
* Copyright © 2016 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
*/
#ifndef __I915_VMA_H__
#define __I915_VMA_H__
#include <linux/io-mapping.h>
#include <linux/rbtree.h>
#include <drm/drm_mm.h>
#include "gt/intel_ggtt_fencing.h"
#include "gem/i915_gem_object.h"
#include "i915_gem_gtt.h"
#include "i915_active.h"
#include "i915_request.h"
#include "i915_vma_resource.h"
#include "i915_vma_types.h"
struct i915_vma *
i915_vma_instance(struct drm_i915_gem_object *obj,
struct i915_address_space *vm,
const struct i915_ggtt_view *view);
void i915_vma_unpin_and_release(struct i915_vma **p_vma, unsigned int flags);
#define I915_VMA_RELEASE_MAP BIT(0)
static inline bool i915_vma_is_active(const struct i915_vma *vma)
{
return !i915_active_is_idle(&vma->active);
}
/* do not reserve memory to prevent deadlocks */
#define __EXEC_OBJECT_NO_RESERVE BIT(31)
int __must_check _i915_vma_move_to_active(struct i915_vma *vma,
struct i915_request *rq,
struct dma_fence *fence,
unsigned int flags);
static inline int __must_check
i915_vma_move_to_active(struct i915_vma *vma, struct i915_request *rq,
unsigned int flags)
{
return _i915_vma_move_to_active(vma, rq, &rq->fence, flags);
}
#define __i915_vma_flags(v) ((unsigned long *)&(v)->flags.counter)
static inline bool i915_vma_is_ggtt(const struct i915_vma *vma)
{
return test_bit(I915_VMA_GGTT_BIT, __i915_vma_flags(vma));
}
static inline bool i915_vma_is_dpt(const struct i915_vma *vma)
{
return i915_is_dpt(vma->vm);
}
static inline bool i915_vma_has_ggtt_write(const struct i915_vma *vma)
{
return test_bit(I915_VMA_GGTT_WRITE_BIT, __i915_vma_flags(vma));
}
static inline void i915_vma_set_ggtt_write(struct i915_vma *vma)
{
GEM_BUG_ON(!i915_vma_is_ggtt(vma));
set_bit(I915_VMA_GGTT_WRITE_BIT, __i915_vma_flags(vma));
}
static inline bool i915_vma_unset_ggtt_write(struct i915_vma *vma)
{
return test_and_clear_bit(I915_VMA_GGTT_WRITE_BIT,
__i915_vma_flags(vma));
}
void i915_vma_flush_writes(struct i915_vma *vma);
static inline bool i915_vma_is_map_and_fenceable(const struct i915_vma *vma)
{
return test_bit(I915_VMA_CAN_FENCE_BIT, __i915_vma_flags(vma));
}
static inline bool i915_vma_set_userfault(struct i915_vma *vma)
{
GEM_BUG_ON(!i915_vma_is_map_and_fenceable(vma));
return test_and_set_bit(I915_VMA_USERFAULT_BIT, __i915_vma_flags(vma));
}
static inline void i915_vma_unset_userfault(struct i915_vma *vma)
{
return clear_bit(I915_VMA_USERFAULT_BIT, __i915_vma_flags(vma));
}
static inline bool i915_vma_has_userfault(const struct i915_vma *vma)
{
return test_bit(I915_VMA_USERFAULT_BIT, __i915_vma_flags(vma));
}
static inline bool i915_vma_is_closed(const struct i915_vma *vma)
{
return !list_empty(&vma->closed_link);
}
static inline u32 i915_ggtt_offset(const struct i915_vma *vma)
{
GEM_BUG_ON(!i915_vma_is_ggtt(vma));
GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
GEM_BUG_ON(upper_32_bits(vma->node.start));
GEM_BUG_ON(upper_32_bits(vma->node.start + vma->node.size - 1));
return lower_32_bits(vma->node.start);
}
static inline u32 i915_ggtt_pin_bias(struct i915_vma *vma)
{
return i915_vm_to_ggtt(vma->vm)->pin_bias;
}
static inline struct i915_vma *i915_vma_get(struct i915_vma *vma)
{
i915_gem_object_get(vma->obj);
return vma;
}
static inline struct i915_vma *i915_vma_tryget(struct i915_vma *vma)
{
if (likely(kref_get_unless_zero(&vma->obj->base.refcount)))
return vma;
return NULL;
}
static inline void i915_vma_put(struct i915_vma *vma)
{
i915_gem_object_put(vma->obj);
}
static inline long
i915_vma_compare(struct i915_vma *vma,
struct i915_address_space *vm,
const struct i915_ggtt_view *view)
{
ptrdiff_t cmp;
GEM_BUG_ON(view && !i915_is_ggtt_or_dpt(vm));
cmp = ptrdiff(vma->vm, vm);
if (cmp)
return cmp;
BUILD_BUG_ON(I915_GGTT_VIEW_NORMAL != 0);
cmp = vma->ggtt_view.type;
if (!view)
return cmp;
cmp -= view->type;
if (cmp)
return cmp;
assert_i915_gem_gtt_types();
/* ggtt_view.type also encodes its size so that we both distinguish
* different views using it as a "type" and also use a compact (no
* accessing of uninitialised padding bytes) memcmp without storing
* an extra parameter or adding more code.
*
* To ensure that the memcmp is valid for all branches of the union,
* even though the code looks like it is just comparing one branch,
* we assert above that all branches have the same address, and that
* each branch has a unique type/size.
*/
BUILD_BUG_ON(I915_GGTT_VIEW_NORMAL >= I915_GGTT_VIEW_PARTIAL);
BUILD_BUG_ON(I915_GGTT_VIEW_PARTIAL >= I915_GGTT_VIEW_ROTATED);
BUILD_BUG_ON(I915_GGTT_VIEW_ROTATED >= I915_GGTT_VIEW_REMAPPED);
BUILD_BUG_ON(offsetof(typeof(*view), rotated) !=
offsetof(typeof(*view), partial));
BUILD_BUG_ON(offsetof(typeof(*view), rotated) !=
offsetof(typeof(*view), remapped));
return memcmp(&vma->ggtt_view.partial, &view->partial, view->type);
}
struct i915_vma_work *i915_vma_work(void);
int i915_vma_bind(struct i915_vma *vma,
enum i915_cache_level cache_level,
u32 flags,
struct i915_vma_work *work,
struct i915_vma_resource *vma_res);
bool i915_gem_valid_gtt_space(struct i915_vma *vma, unsigned long color);
bool i915_vma_misplaced(const struct i915_vma *vma,
u64 size, u64 alignment, u64 flags);
void __i915_vma_set_map_and_fenceable(struct i915_vma *vma);
void i915_vma_revoke_mmap(struct i915_vma *vma);
struct dma_fence *__i915_vma_evict(struct i915_vma *vma, bool async);
int __i915_vma_unbind(struct i915_vma *vma);
int __must_check i915_vma_unbind(struct i915_vma *vma);
int __must_check i915_vma_unbind_async(struct i915_vma *vma, bool trylock_vm);
int __must_check i915_vma_unbind_unlocked(struct i915_vma *vma);
void i915_vma_unlink_ctx(struct i915_vma *vma);
void i915_vma_close(struct i915_vma *vma);
void i915_vma_reopen(struct i915_vma *vma);
static inline struct i915_vma *__i915_vma_get(struct i915_vma *vma)
{
if (kref_get_unless_zero(&vma->ref))
return vma;
return NULL;
}
void i915_vma_release(struct kref *ref);
static inline void __i915_vma_put(struct i915_vma *vma)
{
kref_put(&vma->ref, i915_vma_release);
}
void i915_vma_destroy_locked(struct i915_vma *vma);
void i915_vma_destroy(struct i915_vma *vma);
#define assert_vma_held(vma) dma_resv_assert_held((vma)->obj->base.resv)
static inline void i915_vma_lock(struct i915_vma *vma)
{
dma_resv_lock(vma->obj->base.resv, NULL);
}
static inline void i915_vma_unlock(struct i915_vma *vma)
{
dma_resv_unlock(vma->obj->base.resv);
}
int __must_check
i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
u64 size, u64 alignment, u64 flags);
static inline int __must_check
i915_vma_pin(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
{
struct i915_gem_ww_ctx ww;
int err;
i915_gem_ww_ctx_init(&ww, true);
retry:
err = i915_gem_object_lock(vma->obj, &ww);
if (!err)
err = i915_vma_pin_ww(vma, &ww, size, alignment, flags);
if (err == -EDEADLK) {
err = i915_gem_ww_ctx_backoff(&ww);
if (!err)
goto retry;
}
i915_gem_ww_ctx_fini(&ww);
return err;
}
int i915_ggtt_pin(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
u32 align, unsigned int flags);
static inline int i915_vma_pin_count(const struct i915_vma *vma)
{
return atomic_read(&vma->flags) & I915_VMA_PIN_MASK;
}
static inline bool i915_vma_is_pinned(const struct i915_vma *vma)
{
return i915_vma_pin_count(vma);
}
static inline void __i915_vma_pin(struct i915_vma *vma)
{
atomic_inc(&vma->flags);
GEM_BUG_ON(!i915_vma_is_pinned(vma));
}
static inline void __i915_vma_unpin(struct i915_vma *vma)
{
GEM_BUG_ON(!i915_vma_is_pinned(vma));
atomic_dec(&vma->flags);
}
static inline void i915_vma_unpin(struct i915_vma *vma)
{
GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
__i915_vma_unpin(vma);
}
static inline bool i915_vma_is_bound(const struct i915_vma *vma,
unsigned int where)
{
return atomic_read(&vma->flags) & where;
}
static inline bool i915_node_color_differs(const struct drm_mm_node *node,
unsigned long color)
{
return drm_mm_node_allocated(node) && node->color != color;
}
/**
* i915_vma_pin_iomap - calls ioremap_wc to map the GGTT VMA via the aperture
* @vma: VMA to iomap
*
* The passed in VMA has to be pinned in the global GTT mappable region.
* An extra pinning of the VMA is acquired for the return iomapping,
* the caller must call i915_vma_unpin_iomap to relinquish the pinning
* after the iomapping is no longer required.
*
* Returns a valid iomapped pointer or ERR_PTR.
*/
void __iomem *i915_vma_pin_iomap(struct i915_vma *vma);
#define IO_ERR_PTR(x) ((void __iomem *)ERR_PTR(x))
/**
* i915_vma_unpin_iomap - unpins the mapping returned from i915_vma_iomap
* @vma: VMA to unpin
*
* Unpins the previously iomapped VMA from i915_vma_pin_iomap().
*
* This function is only valid to be called on a VMA previously
* iomapped by the caller with i915_vma_pin_iomap().
*/
void i915_vma_unpin_iomap(struct i915_vma *vma);
/**
* i915_vma_pin_fence - pin fencing state
* @vma: vma to pin fencing for
*
* This pins the fencing state (whether tiled or untiled) to make sure the
* vma (and its object) is ready to be used as a scanout target. Fencing
* status must be synchronize first by calling i915_vma_get_fence():
*
* The resulting fence pin reference must be released again with
* i915_vma_unpin_fence().
*
* Returns:
*
* True if the vma has a fence, false otherwise.
*/
int __must_check i915_vma_pin_fence(struct i915_vma *vma);
void i915_vma_revoke_fence(struct i915_vma *vma);
int __i915_vma_pin_fence(struct i915_vma *vma);
static inline void __i915_vma_unpin_fence(struct i915_vma *vma)
{
GEM_BUG_ON(atomic_read(&vma->fence->pin_count) <= 0);
atomic_dec(&vma->fence->pin_count);
}
/**
* i915_vma_unpin_fence - unpin fencing state
* @vma: vma to unpin fencing for
*
* This releases the fence pin reference acquired through
* i915_vma_pin_fence. It will handle both objects with and without an
* attached fence correctly, callers do not need to distinguish this.
*/
static inline void
i915_vma_unpin_fence(struct i915_vma *vma)
{
if (vma->fence)
__i915_vma_unpin_fence(vma);
}
void i915_vma_parked(struct intel_gt *gt);
static inline bool i915_vma_is_scanout(const struct i915_vma *vma)
{
return test_bit(I915_VMA_SCANOUT_BIT, __i915_vma_flags(vma));
}
static inline void i915_vma_mark_scanout(struct i915_vma *vma)
{
set_bit(I915_VMA_SCANOUT_BIT, __i915_vma_flags(vma));
}
static inline void i915_vma_clear_scanout(struct i915_vma *vma)
{
clear_bit(I915_VMA_SCANOUT_BIT, __i915_vma_flags(vma));
}
#define for_each_until(cond) if (cond) break; else
/**
* for_each_ggtt_vma - Iterate over the GGTT VMA belonging to an object.
* @V: the #i915_vma iterator
* @OBJ: the #drm_i915_gem_object
*
* GGTT VMA are placed at the being of the object's vma_list, see
* vma_create(), so we can stop our walk as soon as we see a ppgtt VMA,
* or the list is empty ofc.
*/
#define for_each_ggtt_vma(V, OBJ) \
list_for_each_entry(V, &(OBJ)->vma.list, obj_link) \
for_each_until(!i915_vma_is_ggtt(V))
struct i915_vma *i915_vma_make_unshrinkable(struct i915_vma *vma);
void i915_vma_make_shrinkable(struct i915_vma *vma);
void i915_vma_make_purgeable(struct i915_vma *vma);
int i915_vma_wait_for_bind(struct i915_vma *vma);
static inline int i915_vma_sync(struct i915_vma *vma)
{
/* Wait for the asynchronous bindings and pending GPU reads */
return i915_active_wait(&vma->active);
}
/**
* i915_vma_get_current_resource - Get the current resource of the vma
* @vma: The vma to get the current resource from.
*
* It's illegal to call this function if the vma is not bound.
*
* Return: A refcounted pointer to the current vma resource
* of the vma, assuming the vma is bound.
*/
static inline struct i915_vma_resource *
i915_vma_get_current_resource(struct i915_vma *vma)
{
return i915_vma_resource_get(vma->resource);
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
void i915_vma_resource_init_from_vma(struct i915_vma_resource *vma_res,
struct i915_vma *vma);
#endif
void i915_vma_module_exit(void);
int i915_vma_module_init(void);
I915_SELFTEST_DECLARE(int i915_vma_get_pages(struct i915_vma *vma));
I915_SELFTEST_DECLARE(void i915_vma_put_pages(struct i915_vma *vma));
#endif