From 5f98ecdbcef1920323d8777c0ba55dbd4335d3cf Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Sun, 5 Jun 2011 11:47:29 +0900 Subject: [PATCH] swiotlb: Export swioltb_nr_tbl and utilize it as appropiate. By default the io_tlb_nslabs is set to zero, and gets set to whatever value is passed in via swiotlb_init_with_tbl function. The default value passed in is 64MB. However, if the user provides the 'swiotlb=' the default value is ignored and the value provided by the user is used... Except when the SWIOTLB is used under Xen - there the default value of 64MB is used and the Xen-SWIOTLB has no mechanism to get the 'io_tlb_nslabs' filled out by setup_io_tlb_npages functions. This patch provides a function for the Xen-SWIOTLB to call to see if the io_tlb_nslabs is set and if so use that value. Signed-off-by: FUJITA Tomonori Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/swiotlb-xen.c | 12 +++++++++--- include/linux/swiotlb.h | 1 + lib/swiotlb.c | 5 +++++ 3 files changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 54469c3..5ac3f48 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -147,9 +147,15 @@ void __init xen_swiotlb_init(int verbose) { unsigned long bytes; int rc; - - xen_io_tlb_nslabs = (64 * 1024 * 1024 >> IO_TLB_SHIFT); - xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, IO_TLB_SEGSIZE); + unsigned long nr_tbl; + + nr_tbl = swioltb_nr_tbl(); + if (nr_tbl) + xen_io_tlb_nslabs = nr_tbl; + else { + xen_io_tlb_nslabs = (64 * 1024 * 1024 >> IO_TLB_SHIFT); + xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, IO_TLB_SEGSIZE); + } bytes = xen_io_tlb_nslabs << IO_TLB_SHIFT; diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 8c0e349..445702c 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -24,6 +24,7 @@ extern int swiotlb_force; extern void swiotlb_init(int verbose); extern void swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose); +extern unsigned long swioltb_nr_tbl(void); /* * Enumeration for sync targets diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 93ca08b..99093b3 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -110,6 +110,11 @@ setup_io_tlb_npages(char *str) __setup("swiotlb=", setup_io_tlb_npages); /* make io_tlb_overflow tunable too? */ +unsigned long swioltb_nr_tbl(void) +{ + return io_tlb_nslabs; +} + /* Note that this doesn't work with highmem page */ static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev, volatile void *address) -- 2.7.4