diff options
| author | Stefano Stabellini <stefanos@xilinx.com> | 2019-05-29 01:48:22 +0300 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2019-06-05 17:09:26 +0300 |
| commit | 4e7372e0dc5d7d2078fbdb13505635cd5b11f93d (patch) | |
| tree | fae9f967cff6fa82ec939db85f676dda5caef8e8 /drivers/xen | |
| parent | 063b8271ec8f706d833e61dfca40c512504a62c1 (diff) | |
| download | linux-4e7372e0dc5d7d2078fbdb13505635cd5b11f93d.tar.xz | |
xen/swiotlb: don't initialize swiotlb twice on arm64
On arm64 swiotlb is often (not always) already initialized by mem_init.
We don't want to initialize it twice, which would trigger a second
memory allocation. Moreover, the second memory pool is typically made of
high pages and ends up replacing the original memory pool of low pages.
As a side effect of this change, it is possible to have low pages in
swiotlb-xen on arm64.
Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'drivers/xen')
| -rw-r--r-- | drivers/xen/swiotlb-xen.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 64cb94dfedd4..342762b1aefb 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -211,6 +211,15 @@ int __ref xen_swiotlb_init(int verbose, bool early) retry: bytes = xen_set_nslabs(xen_io_tlb_nslabs); order = get_order(xen_io_tlb_nslabs << IO_TLB_SHIFT); + + /* + * IO TLB memory already allocated. Just use it. + */ + if (io_tlb_start != 0) { + xen_io_tlb_start = phys_to_virt(io_tlb_start); + goto end; + } + /* * Get IO TLB memory from any location. */ @@ -237,7 +246,6 @@ retry: m_ret = XEN_SWIOTLB_ENOMEM; goto error; } - xen_io_tlb_end = xen_io_tlb_start + bytes; /* * And replace that memory with pages under 4GB. */ @@ -264,6 +272,8 @@ retry: } else rc = swiotlb_late_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs); +end: + xen_io_tlb_end = xen_io_tlb_start + bytes; if (!rc) swiotlb_set_max_segment(PAGE_SIZE); |