vhost: factor out IOTLB

This patch factors out IOTLB into a dedicated module in order to be reused by other modules like vringh. User may choose to enable the automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit for the case of vhost device IOTLB implementation.

Jason Wang committed 6 years ago

Commit 0bbe3061 parent 792a4f28 files · +315 −181Browse files

Showing the changes to include/linux (1 of 8 files). Show all

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include/linux/vhost_iotlb.h+47−0

@@ -0,0 +1,47 @@
	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef _LINUX_VHOST_IOTLB_H
	3	#define _LINUX_VHOST_IOTLB_H
	4
	5	#include <linux/interval_tree_generic.h>
	6
	7	struct vhost_iotlb_map {
	8	struct rb_node rb;
	9	struct list_head link;
	10	u64 start;
	11	u64 last;
	12	u64 size;
	13	u64 addr;
	14	#define VHOST_MAP_RO 0x1
	15	#define VHOST_MAP_WO 0x2
	16	#define VHOST_MAP_RW 0x3
	17	u32 perm;
	18	u32 flags_padding;
	19	u64 __subtree_last;
	20	};
	21
	22	#define VHOST_IOTLB_FLAG_RETIRE 0x1
	23
	24	struct vhost_iotlb {
	25	struct rb_root_cached root;
	26	struct list_head list;
	27	unsigned int limit;
	28	unsigned int nmaps;
	29	unsigned int flags;
	30	};
	31
	32	int vhost_iotlb_add_range(struct vhost_iotlb *iotlb, u64 start, u64 last,
	33	u64 addr, unsigned int perm);
	34	void vhost_iotlb_del_range(struct vhost_iotlb *iotlb, u64 start, u64 last);
	35
	36	struct vhost_iotlb *vhost_iotlb_alloc(unsigned int limit, unsigned int flags);
	37	void vhost_iotlb_free(struct vhost_iotlb *iotlb);
	38	void vhost_iotlb_reset(struct vhost_iotlb *iotlb);
	39
	40	struct vhost_iotlb_map *
	41	vhost_iotlb_itree_first(struct vhost_iotlb *iotlb, u64 start, u64 last);
	42	struct vhost_iotlb_map *
	43	vhost_iotlb_itree_next(struct vhost_iotlb_map *map, u64 start, u64 last);
	44
	45	void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
	46	struct vhost_iotlb_map *map);
	47	#endif