From bb99332a2b558e1f28b4c5011f9ea3b46f1c8806 Mon Sep 17 00:00:00 2001 From: Halil Pasic Date: Tue, 2 Apr 2019 18:47:29 +0200 Subject: s390/cio: introduce DMA pools to cio To support protected virtualization cio will need to make sure the memory used for communication with the hypervisor is DMA memory. Let us introduce one global pool for cio. Our DMA pools are implemented as a gen_pool backed with DMA pages. The idea is to avoid each allocation effectively wasting a page, as we typically allocate much less than PAGE_SIZE. Signed-off-by: Halil Pasic Reviewed-by: Sebastian Ott Reviewed-by: Cornelia Huck Reviewed-by: Michael Mueller Tested-by: Michael Mueller Signed-off-by: Heiko Carstens --- arch/s390/Kconfig | 1 + arch/s390/include/asm/cio.h | 11 +++++++++++ 2 files changed, 12 insertions(+) (limited to 'arch') diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 35bb76491600..fdb4246265a5 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -190,6 +190,7 @@ config S390 select ARCH_HAS_SCALED_CPUTIME select HAVE_NMI select SWIOTLB + select GENERIC_ALLOCATOR config SCHED_OMIT_FRAME_POINTER diff --git a/arch/s390/include/asm/cio.h b/arch/s390/include/asm/cio.h index 1727180e8ca1..58e7db912c30 100644 --- a/arch/s390/include/asm/cio.h +++ b/arch/s390/include/asm/cio.h @@ -7,6 +7,7 @@ #include #include +#include #include #define LPM_ANYPATH 0xff @@ -328,6 +329,16 @@ static inline u8 pathmask_to_pos(u8 mask) void channel_subsystem_reinit(void); extern void css_schedule_reprobe(void); +extern void *cio_dma_zalloc(size_t size); +extern void cio_dma_free(void *cpu_addr, size_t size); +extern struct device *cio_get_dma_css_dev(void); + +void *cio_gp_dma_zalloc(struct gen_pool *gp_dma, struct device *dma_dev, + size_t size); +void cio_gp_dma_free(struct gen_pool *gp_dma, void *cpu_addr, size_t size); +void cio_gp_dma_destroy(struct gen_pool *gp_dma, struct device *dma_dev); +struct gen_pool *cio_gp_dma_create(struct device *dma_dev, int nr_pages); + /* Function from drivers/s390/cio/chsc.c */ int chsc_sstpc(void *page, unsigned int op, u16 ctrl, u64 *clock_delta); int chsc_sstpi(void *page, void *result, size_t size); -- cgit v1.2.3-59-g8ed1b