Commit b723caec authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Linus Torvalds
Browse files

xen/xenbus: use apply_to_page_range directly in xenbus_map_ring_pv 



Replacing alloc_vm_area with get_vm_area_caller + apply_page_range allows
to fill put the phys_addr values directly instead of doing another loop
over all addresses.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Link: https://lkml.kernel.org/r/20201002122204.1534411-10-hch@lst.de


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 534a6687

drivers/xen/xenbus/xenbus_client.c

+16 −14
Original line number Diff line number Diff line
@@ -73,16 +73,13 @@ struct map_ring_valloc { 
	struct xenbus_map_node *node;



	/* Why do we need two arrays? See comment of __xenbus_map_ring */

	union {

	unsigned long addrs[XENBUS_MAX_RING_GRANTS];

		pte_t *ptes[XENBUS_MAX_RING_GRANTS];

	};

	phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];



	struct gnttab_map_grant_ref map[XENBUS_MAX_RING_GRANTS];

	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_GRANTS];



	unsigned int idx;	/* HVM only. */

	unsigned int idx;

};



static DEFINE_SPINLOCK(xenbus_valloc_lock);
@@ -686,6 +683,14 @@ int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr) 
EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);



#ifdef CONFIG_XEN_PV

static int map_ring_apply(pte_t *pte, unsigned long addr, void *data)

{

	struct map_ring_valloc *info = data;



	info->phys_addrs[info->idx++] = arbitrary_virt_to_machine(pte).maddr;

	return 0;

}



static int xenbus_map_ring_pv(struct xenbus_device *dev,

			      struct map_ring_valloc *info,

			      grant_ref_t *gnt_refs,
@@ -694,18 +699,15 @@ static int xenbus_map_ring_pv(struct xenbus_device *dev, 
{

	struct xenbus_map_node *node = info->node;

	struct vm_struct *area;

	int err = GNTST_okay;

	int i;

	bool leaked;

	bool leaked = false;

	int err = -ENOMEM;



	area = alloc_vm_area(XEN_PAGE_SIZE * nr_grefs, info->ptes);

	area = get_vm_area(XEN_PAGE_SIZE * nr_grefs, VM_IOREMAP);

	if (!area)

		return -ENOMEM;



	for (i = 0; i < nr_grefs; i++)

		info->phys_addrs[i] =

			arbitrary_virt_to_machine(info->ptes[i]).maddr;



	if (apply_to_page_range(&init_mm, (unsigned long)area->addr,

				XEN_PAGE_SIZE * nr_grefs, map_ring_apply, info))

		goto failed;

	err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles,

				info, GNTMAP_host_map | GNTMAP_contains_pte,

				&leaked);

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