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arm64: do not set SWIOTLB_NO_FORCE when swiotlb is required

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Although SWIOTLB_NO_FORCE is meant to allow later calls to swiotlb_init,
today dma_direct_map_page returns error if SWIOTLB_NO_FORCE.

For now, without a larger overhaul of SWIOTLB_NO_FORCE, the best we can
do is to avoid setting SWIOTLB_NO_FORCE in mem_init when we know that it
is going to be required later (e.g. Xen requires it).

CC: boris.ostrovsky@oracle.com
CC: jgross@suse.com
CC: catalin.marinas@arm.com
CC: will@kernel.org
CC: linux-arm-kernel@lists.infradead.org
Fixes: 2726bf3ff2 ("swiotlb: Make SWIOTLB_NO_FORCE perform no allocation")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210512201823.1963-2-sstabellini@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Christoph Hellwig 2021-05-12 13:18:22 -07:00 committed by Juergen Gross
parent cb6f6b3384
commit 687842ec50
1 changed files with 2 additions and 1 deletions
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3
arch/arm64/mm/init.c
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@ -43,6 +43,7 @@
#include <linux/sizes.h>
#include <asm/tlb.h>
#include <asm/alternative.h>
#include <asm/xen/swiotlb-xen.h>
/*
* We need to be able to catch inadvertent references to memstart_addr
@ -482,7 +483,7 @@ void __init mem_init(void)
if (swiotlb_force == SWIOTLB_FORCE ||
max_pfn > PFN_DOWN(arm64_dma_phys_limit))
swiotlb_init(1);
else
else if (!xen_swiotlb_detect())
swiotlb_force = SWIOTLB_NO_FORCE;
set_max_mapnr(max_pfn - PHYS_PFN_OFFSET);