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authorHalil Pasic <pasic@linux.ibm.com>2019-04-02 19:47:29 +0300
committerHeiko Carstens <heiko.carstens@de.ibm.com>2019-06-15 13:24:56 +0300
commitbb99332a2b558e1f28b4c5011f9ea3b46f1c8806 (patch)
treef6412179ed9826c356de539543164a32206cb76a /arch/s390/include/asm/cio.h
parent64e1f0c531d1072cd97939bf0d8df42b26713543 (diff)
downloadlinux-bb99332a2b558e1f28b4c5011f9ea3b46f1c8806.tar.xz
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 <pasic@linux.ibm.com> Reviewed-by: Sebastian Ott <sebott@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Michael Mueller <mimu@linux.ibm.com> Tested-by: Michael Mueller <mimu@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Diffstat (limited to 'arch/s390/include/asm/cio.h')
-rw-r--r--arch/s390/include/asm/cio.h11
1 files changed, 11 insertions, 0 deletions
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 <linux/spinlock.h>
#include <linux/bitops.h>
+#include <linux/genalloc.h>
#include <asm/types.h>
#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);