[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PATCH v3 10/21] xen/shbuf: switch xen-front-pgdir-shbuf to use INVALID_GRANT_REF




On 05.05.22 11:16, Juergen Gross wrote:


Hello Juergen


Instead of using a private macro for an invalid grant reference use
the common one.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
V3:
- terminate grant ref list with 0 (Oleksandr Tyshchenko)


Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>


---
  drivers/xen/xen-front-pgdir-shbuf.c | 18 +++++-------------
  1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/drivers/xen/xen-front-pgdir-shbuf.c 
b/drivers/xen/xen-front-pgdir-shbuf.c
index a959dee21134..b6433761d42c 100644
--- a/drivers/xen/xen-front-pgdir-shbuf.c
+++ b/drivers/xen/xen-front-pgdir-shbuf.c
@@ -21,15 +21,6 @@
#include <xen/xen-front-pgdir-shbuf.h> -#ifndef GRANT_INVALID_REF
-/*
- * FIXME: usage of grant reference 0 as invalid grant reference:
- * grant reference 0 is valid, but never exposed to a PV driver,
- * because of the fact it is already in use/reserved by the PV console.
- */
-#define GRANT_INVALID_REF      0
-#endif
-
  /**
   * This structure represents the structure of a shared page
   * that contains grant references to the pages of the shared
@@ -38,6 +29,7 @@
   */
  struct xen_page_directory {
        grant_ref_t gref_dir_next_page;
+#define XEN_GREF_LIST_END      0
        grant_ref_t gref[1]; /* Variable length */
  };
@@ -83,7 +75,7 @@ grant_ref_t
  xen_front_pgdir_shbuf_get_dir_start(struct xen_front_pgdir_shbuf *buf)
  {
        if (!buf->grefs)
-               return GRANT_INVALID_REF;
+               return INVALID_GRANT_REF;
return buf->grefs[0];
  }
@@ -142,7 +134,7 @@ void xen_front_pgdir_shbuf_free(struct 
xen_front_pgdir_shbuf *buf)
                int i;
for (i = 0; i < buf->num_grefs; i++)
-                       if (buf->grefs[i] != GRANT_INVALID_REF)
+                       if (buf->grefs[i] != INVALID_GRANT_REF)
                                gnttab_end_foreign_access(buf->grefs[i], 0UL);
        }
        kfree(buf->grefs);
@@ -355,7 +347,7 @@ static void backend_fill_page_dir(struct 
xen_front_pgdir_shbuf *buf)
        }
        /* Last page must say there is no more pages. */
        page_dir = (struct xen_page_directory *)ptr;
-       page_dir->gref_dir_next_page = GRANT_INVALID_REF;
+       page_dir->gref_dir_next_page = XEN_GREF_LIST_END;
  }
/**
@@ -384,7 +376,7 @@ static void guest_fill_page_dir(struct 
xen_front_pgdir_shbuf *buf)
if (grefs_left <= XEN_NUM_GREFS_PER_PAGE) {
                        to_copy = grefs_left;
-                       page_dir->gref_dir_next_page = GRANT_INVALID_REF;
+                       page_dir->gref_dir_next_page = XEN_GREF_LIST_END;
                } else {
                        to_copy = XEN_NUM_GREFS_PER_PAGE;
                        page_dir->gref_dir_next_page = buf->grefs[i + 1];

--
Regards,

Oleksandr Tyshchenko




 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.