Commit d0cfb9dc authored by Vivek Goyal's avatar Vivek Goyal Committed by Miklos Szeredi
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virtiofs: maintain a list of busy elements 



This list will be used selecting fuse_dax_mapping to free when number of
free mappings drops below a threshold.

Signed-off-by: default avatarVivek Goyal <vgoyal@redhat.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 6ae330ca

fs/fuse/dax.c

+25 −0
Original line number Diff line number Diff line
@@ -28,6 +28,9 @@ struct fuse_dax_mapping { 
	/* For interval tree in file/inode */

	struct interval_tree_node itn;



	/* Will connect in fc->busy_ranges to keep track busy memory */

	struct list_head busy_list;



	/** Position in DAX window */

	u64 window_offset;
@@ -55,6 +58,10 @@ struct fuse_conn_dax { 
	/* Lock protecting accessess to  members of this structure */

	spinlock_t lock;



	/* List of memory ranges which are busy */

	unsigned long nr_busy_ranges;

	struct list_head busy_ranges;



	/* DAX Window Free Ranges */

	long nr_free_ranges;

	struct list_head free_ranges;
@@ -85,6 +92,15 @@ static struct fuse_dax_mapping *alloc_dax_mapping(struct fuse_conn_dax *fcd) 
	return dmap;

}



/* This assumes fcd->lock is held */

static void __dmap_remove_busy_list(struct fuse_conn_dax *fcd,

				    struct fuse_dax_mapping *dmap)

{

	list_del_init(&dmap->busy_list);

	WARN_ON(fcd->nr_busy_ranges == 0);

	fcd->nr_busy_ranges--;

}



/* This assumes fcd->lock is held */

static void __dmap_add_to_free_pool(struct fuse_conn_dax *fcd,

				struct fuse_dax_mapping *dmap)
@@ -139,6 +155,10 @@ static int fuse_setup_one_mapping(struct inode *inode, unsigned long start_idx, 
		/* Protected by fi->dax->sem */

		interval_tree_insert(&dmap->itn, &fi->dax->tree);

		fi->dax->nr++;

		spin_lock(&fcd->lock);

		list_add_tail(&dmap->busy_list, &fcd->busy_ranges);

		fcd->nr_busy_ranges++;

		spin_unlock(&fcd->lock);

	}

	return 0;

}
@@ -207,6 +227,7 @@ static void dmap_reinit_add_to_free_pool(struct fuse_conn_dax *fcd, 
	pr_debug("fuse: freeing memory range start_idx=0x%lx end_idx=0x%lx window_offset=0x%llx length=0x%llx\n",

		 dmap->itn.start, dmap->itn.last, dmap->window_offset,

		 dmap->length);

	__dmap_remove_busy_list(fcd, dmap);

	dmap->itn.start = dmap->itn.last = 0;

	__dmap_add_to_free_pool(fcd, dmap);

}
@@ -700,6 +721,8 @@ static void fuse_free_dax_mem_ranges(struct list_head *mem_list) 
	/* Free All allocated elements */

	list_for_each_entry_safe(range, temp, mem_list, list) {

		list_del(&range->list);

		if (!list_empty(&range->busy_list))

			list_del(&range->busy_list);

		kfree(range);

	}

}
@@ -723,6 +746,7 @@ static int fuse_dax_mem_range_init(struct fuse_conn_dax *fcd) 
	unsigned long i;



	INIT_LIST_HEAD(&fcd->free_ranges);

	INIT_LIST_HEAD(&fcd->busy_ranges);

	id = dax_read_lock();

	nr_pages = dax_direct_access(fcd->dev, 0, PHYS_PFN(dax_size), &kaddr,

				     &pfn);
@@ -748,6 +772,7 @@ static int fuse_dax_mem_range_init(struct fuse_conn_dax *fcd) 
		 */

		range->window_offset = i * FUSE_DAX_SZ;

		range->length = FUSE_DAX_SZ;

		INIT_LIST_HEAD(&range->busy_list);

		list_add_tail(&range->list, &fcd->free_ranges);

	}