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authorDongli Zhang <dongli.zhang@oracle.com>2019-01-18 15:10:28 +0800
committerKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>2019-02-12 12:53:01 -0500
commit60513ed06a41049768a6875229b025b6e726e148 (patch)
tree4c674fb2f2dcae13ba33ff82f0e937a66ce3b2e7 /kernel/dma
parent71602fe6d4e9291af105adfef8e893b57c735906 (diff)
downloadlinux-60513ed06a41049768a6875229b025b6e726e148.tar.bz2
swiotlb: checking whether swiotlb buffer is full with io_tlb_used
This patch uses io_tlb_used to help check whether swiotlb buffer is full. io_tlb_used is no longer used for only debugfs. It is also used to help optimize swiotlb_tbl_map_single(). Suggested-by: Joe Jin <joe.jin@oracle.com> Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'kernel/dma')
-rw-r--r--kernel/dma/swiotlb.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index bedc9f945836..a01b83e95a2a 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -483,6 +483,10 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
* request and allocate a buffer from that IO TLB pool.
*/
spin_lock_irqsave(&io_tlb_lock, flags);
+
+ if (unlikely(nslots > io_tlb_nslabs - io_tlb_used))
+ goto not_found;
+
index = ALIGN(io_tlb_index, stride);
if (index >= io_tlb_nslabs)
index = 0;