[PATCH 4.14 28/31] xen: remove gnttab_query_foreign_access()

Greg Kroah-Hartman
2022-03-10T14:26:26Z

From: Juergen Gross <jgross@suse.com>

Commit 1dbd11ca75fe664d3e54607547771d021f531f59 upstream.

Remove gnttab_query_foreign_access(), as it is unused and unsafe to
use.

All previous use cases assumed a grant would not be in use after
gnttab_query_foreign_access() returned 0. This information is useless
in best case, as it only refers to a situation in the past, which could
have changed already.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/xen/grant-table.c | 19 -------------------
include/xen/grant_table.h | 2 --
2 files changed, 21 deletions(-)

--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -114,13 +114,6 @@ struct gnttab_ops {
* return the frame.
*/
unsigned long (*end_foreign_transfer_ref)(grant_ref_t ref);
- /*
- * Query the status of a grant entry. Ref parameter is reference of
- * queried grant entry, return value is the status of queried entry.
- * Detailed status(writing/reading) can be gotten from the return value
- * by bit operations.
- */
- int (*query_foreign_access)(grant_ref_t ref);
};

struct unmap_refs_callback_data {
@@ -255,17 +248,6 @@ int gnttab_grant_foreign_access(domid_t
}
EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access);

-static int gnttab_query_foreign_access_v1(grant_ref_t ref)
-{
- return gnttab_shared.v1[ref].flags & (GTF_reading|GTF_writing);
-}
-
-int gnttab_query_foreign_access(grant_ref_t ref)
-{
- return gnttab_interface->query_foreign_access(ref);
-}
-EXPORT_SYMBOL_GPL(gnttab_query_foreign_access);
-
static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly)
{
u16 flags, nflags;
@@ -1029,7 +1011,6 @@ static const struct gnttab_ops gnttab_v1
.update_entry = gnttab_update_entry_v1,
.end_foreign_access_ref = gnttab_end_foreign_access_ref_v1,
.end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v1,
- .query_foreign_access = gnttab_query_foreign_access_v1,
};

static void gnttab_request_version(void)
--- a/include/xen/grant_table.h
+++ b/include/xen/grant_table.h
@@ -118,8 +118,6 @@ int gnttab_grant_foreign_transfer(domid_
unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);

-int gnttab_query_foreign_access(grant_ref_t ref);
-
/*
* operations on reserved batches of grant references
*/