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=<nslabs>' 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 <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
FUJITA Tomonori 2011-06-05 11:47:29 +09:00 committed by Konrad Rzeszutek Wilk
parent 61c4f2c81c
commit 5f98ecdbce
3 changed files with 14 additions and 2 deletions

View file

@ -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