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Each GDMA queue ring is one dma_alloc_coherent() of the whole ring size. Such high-order allocations fail first under memory fragmentation, so queue setup can fail with memory still free. The hardware does not need the ring physically contiguous: mana_gd_create_dma_region() already maps it as a list of MANA_PAGE_SIZE (4K) device addresses. Only the driver's linear CPU view needs contiguity, and it goes through mana_gd_ring_ptr() and mana_gd_ring_contig_avail(); change both to map offsets onto scattered pages. Add a fallback in mana_gd_alloc_memory(): data-path queues pass allow_scatter=true, so when the contiguous allocation fails the ring is backed by a vector of scattered PAGE_SIZE (order-0) coherent pages, presenting the same DMA page-list layout to the device. The HW channel bootstrap keeps allow_scatter=false, and the debugfs ring dumper reads scattered rings through the same helpers. Signed-off-by: Aditya Garg <gargaditya@linux.microsoft.com> Link: https://patch.msgid.link/20260807210002.1695263-3-gargaditya@linux.microsoft.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>