From d9a0c859a8faeda9b7cbefbba1bed6f2cfd75a0a Mon Sep 17 00:00:00 2001 From: Stanislav Kinsburskii Date: Thu, 23 Jul 2026 10:36:38 -0700 Subject: RDMA/umem: use hmm_range_fault_unlocked_timeout() for ODP faults ib_umem_odp_map_dma_and_lock() takes mmap_read_lock() only around hmm_range_fault(), then retries -EBUSY until HMM_RANGE_DEFAULT_TIMEOUT expires. Use hmm_range_fault_unlocked_timeout() instead. The HMM helper now owns the mmap lock and refreshes range->notifier_seq for its internal retries. ODP keeps using HMM_RANGE_DEFAULT_TIMEOUT for each HMM fault attempt, while interval invalidation retries continue to be handled by the existing outer loop. ODP still validates the interval notifier sequence while holding umem_mutex before DMA mapping pages. Link: https://lore.kernel.org/20260723-hmm-v10-v11-6-c55b003a4b61@gmail.com Signed-off-by: Stanislav Kinsburskii Reviewed-by: Jason Gunthorpe Cc: Danilo Krummrich Cc: Dave Airlie Cc: David Hildenbrand Cc: Dexuan Cui Cc: Haiyang Zhang Cc: Jonathan Corbet Cc: K. Y. Srinivasan Cc: Leon Romanovsky Cc: Liam R. Howlett Cc: Lizhi Hou Cc: Long Li Cc: Lorenzo Stoakes Cc: Lyude Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Michal Hocko Cc: Mike Rapoport Cc: Oded Gabbay Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Thomas Zimemrmann Cc: Vlastimil Babka Cc: Wei Liu Signed-off-by: Andrew Morton --- drivers/infiniband/core/umem_odp.c | 18 +++++------------- 1 file changed, 5 insertions(+), 13 deletions(-) (limited to 'drivers/infiniband/core') diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c index 404fa1cc3254..9cc21cd762d9 100644 --- a/drivers/infiniband/core/umem_odp.c +++ b/drivers/infiniband/core/umem_odp.c @@ -329,7 +329,7 @@ int ib_umem_odp_map_dma_and_lock(struct ib_umem_odp *umem_odp, u64 user_virt, struct mm_struct *owning_mm = umem_odp->umem.owning_mm; int pfn_index, dma_index, ret = 0, start_idx; unsigned int page_shift, hmm_order, pfn_start_idx; - unsigned long num_pfns, current_seq; + unsigned long num_pfns; struct hmm_range range = {}; unsigned long timeout; @@ -363,26 +363,18 @@ int ib_umem_odp_map_dma_and_lock(struct ib_umem_odp *umem_odp, u64 user_virt, } range.hmm_pfns = &(umem_odp->map.pfn_list[pfn_start_idx]); - timeout = jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT); + timeout = msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT); retry: - current_seq = range.notifier_seq = - mmu_interval_read_begin(&umem_odp->notifier); - - mmap_read_lock(owning_mm); - ret = hmm_range_fault(&range); - mmap_read_unlock(owning_mm); - if (unlikely(ret)) { - if (ret == -EBUSY && !time_after(jiffies, timeout)) - goto retry; + ret = hmm_range_fault_unlocked_timeout(&range, timeout); + if (unlikely(ret)) goto out_put_mm; - } start_idx = (range.start - ib_umem_start(umem_odp)) >> page_shift; dma_index = start_idx; mutex_lock(&umem_odp->umem_mutex); - if (mmu_interval_read_retry(&umem_odp->notifier, current_seq)) { + if (mmu_interval_read_retry(&umem_odp->notifier, range.notifier_seq)) { mutex_unlock(&umem_odp->umem_mutex); goto retry; } -- cgit v1.2.3