From 95d1deb02a9c93bf9ea8cebe61f0c26cadf43cf9 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Mon, 11 Apr 2022 14:58:38 -0700 Subject: drm/msm/gem: Add fenced vma unpin With userspace allocated iova (next patch), we can have a race condition where userspace observes the fence completion and deletes the vma before retire_submit() gets around to unpinning the vma. To handle this, add a fenced unpin which drops the refcount but tracks the fence, and update msm_gem_vma_inuse() to check any previously unsignaled fences. v2: Fix inuse underflow (duplicate unpin) v3: Fix msm_job_run() vs submit_cleanup() race condition Signed-off-by: Rob Clark Link: https://lore.kernel.org/r/20220411215849.297838-10-robdclark@gmail.com Signed-off-by: Rob Clark --- drivers/gpu/drm/msm/msm_gem_vma.c | 30 +++++++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) (limited to 'drivers/gpu/drm/msm/msm_gem_vma.c') diff --git a/drivers/gpu/drm/msm/msm_gem_vma.c b/drivers/gpu/drm/msm/msm_gem_vma.c index 4949899f1fc7..0cd6770faf41 100644 --- a/drivers/gpu/drm/msm/msm_gem_vma.c +++ b/drivers/gpu/drm/msm/msm_gem_vma.c @@ -5,6 +5,7 @@ */ #include "msm_drv.h" +#include "msm_fence.h" #include "msm_gem.h" #include "msm_mmu.h" @@ -39,7 +40,19 @@ msm_gem_address_space_get(struct msm_gem_address_space *aspace) bool msm_gem_vma_inuse(struct msm_gem_vma *vma) { - return !!vma->inuse; + if (vma->inuse > 0) + return true; + + while (vma->fence_mask) { + unsigned idx = ffs(vma->fence_mask) - 1; + + if (!msm_fence_completed(vma->fctx[idx], vma->fence[idx])) + return true; + + vma->fence_mask &= ~BIT(idx); + } + + return false; } /* Actually unmap memory for the vma */ @@ -63,13 +76,24 @@ void msm_gem_purge_vma(struct msm_gem_address_space *aspace, } /* Remove reference counts for the mapping */ -void msm_gem_unmap_vma(struct msm_gem_address_space *aspace, - struct msm_gem_vma *vma) +void msm_gem_unpin_vma(struct msm_gem_vma *vma) { + if (GEM_WARN_ON(!vma->inuse)) + return; if (!GEM_WARN_ON(!vma->iova)) vma->inuse--; } +/* Replace pin reference with fence: */ +void msm_gem_unpin_vma_fenced(struct msm_gem_vma *vma, struct msm_fence_context *fctx) +{ + vma->fctx[fctx->index] = fctx; + vma->fence[fctx->index] = fctx->last_fence; + vma->fence_mask |= BIT(fctx->index); + msm_gem_unpin_vma(vma); +} + +/* Map and pin vma: */ int msm_gem_map_vma(struct msm_gem_address_space *aspace, struct msm_gem_vma *vma, int prot, -- cgit v1.2.3