[PATCH v3 21/21] xen/xenbus: eliminate xenbus_grant_ring()

Juergen Gross
2022-05-05T08:19:30Z

There is no external user of xenbus_grant_ring() left, so merge it into
the only caller xenbus_setup_ring().

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
---
V2:
- make error message more precise (Andrew Cooper)
---
drivers/xen/xenbus/xenbus_client.c | 65 +++++++++---------------------
include/xen/xenbus.h | 2 -
2 files changed, 19 insertions(+), 48 deletions(-)

diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 1a2e0d94ccd1..d6fdd2d209d3 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -363,50 +363,6 @@ static void xenbus_switch_fatal(struct xenbus_device *dev, int depth, int err,
__xenbus_switch_state(dev, XenbusStateClosing, 1);
}

-/**
- * xenbus_grant_ring
- * @dev: xenbus device
- * @vaddr: starting virtual address of the ring
- * @nr_pages: number of pages to be granted
- * @grefs: grant reference array to be filled in
- *
- * Grant access to the given @vaddr to the peer of the given device.
- * Then fill in @grefs with grant references. Return 0 on success, or
- * -errno on error. On error, the device will switch to
- * XenbusStateClosing, and the error will be saved in the store.
- */
-int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
- unsigned int nr_pages, grant_ref_t *grefs)
-{
- int err;
- unsigned int i;
- grant_ref_t gref_head;
-
- err = gnttab_alloc_grant_references(nr_pages, &gref_head);
- if (err) {
- xenbus_dev_fatal(dev, err, "granting access to ring page");
- return err;
- }
-
- for (i = 0; i < nr_pages; i++) {
- unsigned long gfn;
-
- if (is_vmalloc_addr(vaddr))
- gfn = pfn_to_gfn(vmalloc_to_pfn(vaddr));
- else
- gfn = virt_to_gfn(vaddr);
-
- grefs[i] = gnttab_claim_grant_reference(&gref_head);
- gnttab_grant_foreign_access_ref(grefs[i], dev->otherend_id,
- gfn, 0);
-
- vaddr = vaddr + XEN_PAGE_SIZE;
- }
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(xenbus_grant_ring);
-
/*
* xenbus_setup_ring
* @dev: xenbus device
@@ -424,6 +380,7 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
unsigned int nr_pages, grant_ref_t *grefs)
{
unsigned long ring_size = nr_pages * XEN_PAGE_SIZE;
+ grant_ref_t gref_head;
unsigned int i;
int ret;

@@ -433,9 +390,25 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
goto err;
}

- ret = xenbus_grant_ring(dev, *vaddr, nr_pages, grefs);
- if (ret)
+ ret = gnttab_alloc_grant_references(nr_pages, &gref_head);
+ if (ret) {
+ xenbus_dev_fatal(dev, ret, "granting access to %u ring pages",
+ nr_pages);
goto err;
+ }
+
+ for (i = 0; i < nr_pages; i++) {
+ unsigned long gfn;
+
+ if (is_vmalloc_addr(*vaddr))
+ gfn = pfn_to_gfn(vmalloc_to_pfn(vaddr[i]));
+ else
+ gfn = virt_to_gfn(vaddr[i]);
+
+ grefs[i] = gnttab_claim_grant_reference(&gref_head);
+ gnttab_grant_foreign_access_ref(grefs[i], dev->otherend_id,
+ gfn, 0);
+ }

return 0;

diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h
index b533b4adc835..eaa932b99d8a 100644
--- a/include/xen/xenbus.h
+++ b/include/xen/xenbus.h
@@ -224,8 +224,6 @@ int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
const char *pathfmt, ...);

int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
-int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
- unsigned int nr_pages, grant_ref_t *grefs);
int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
unsigned int nr_pages, grant_ref_t *grefs);
void xenbus_teardown_ring(void **vaddr, unsigned int nr_pages,
--
2.35.3