[Xen-devel] [PATCH] xen: clean up gnttab interface

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

- make readonly argument flags instead
- no need to repeat flags when ending a grant

Partially taken from 2.6.18-xen 312:037c44559e55

Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
---
 drivers/block/xen-blkfront.c |   12 ++++++------
 drivers/net/xen-netfront.c   |   16 +++++++---------
 drivers/xen/grant-table.c    |   16 +++++++---------
 include/xen/grant_table.h    |    7 +++----
 4 files changed, 23 insertions(+), 28 deletions(-)

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 8f90508..f834e64 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -254,7 +254,7 @@ static int blkif_queue_request(struct request *req)
                                ref,
                                info->xbdev->otherend_id,
                                buffer_mfn,
-                               rq_data_dir(req) );
+                               rq_data_dir(req) ? GTF_readonly : 0);
 
                info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn);
                ring_req->seg[i] =
@@ -511,7 +511,7 @@ static void blkif_free(struct blkfront_info *info, int 
suspend)
 
        /* Free resources associated with old device channel. */
        if (info->ring_ref != GRANT_INVALID_REF) {
-               gnttab_end_foreign_access(info->ring_ref, 0,
+               gnttab_end_foreign_access(info->ring_ref,
                                          (unsigned long)info->ring.sring);
                info->ring_ref = GRANT_INVALID_REF;
                info->ring.sring = NULL;
@@ -526,7 +526,7 @@ static void blkif_completion(struct blk_shadow *s)
 {
        int i;
        for (i = 0; i < s->req.nr_segments; i++)
-               gnttab_end_foreign_access(s->req.seg[i].gref, 0, 0UL);
+               gnttab_end_foreign_access(s->req.seg[i].gref, 0UL);
 }
 
 static irqreturn_t blkif_interrupt(int irq, void *dev_id)
@@ -809,9 +809,9 @@ static int blkif_recover(struct blkfront_info *info)
                                req->seg[j].gref,
                                info->xbdev->otherend_id,
                                pfn_to_mfn(info->shadow[req->id].frame[j]),
-                               rq_data_dir(
-                                       (struct request *)
-                                       info->shadow[req->id].request));
+                               rq_data_dir((struct request *)
+                                           info->shadow[req->id].request) ?
+                                           GTF_readonly : 0);
                info->shadow[req->id].req = *req;
 
                info->ring.req_prod_pvt++;
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index cd6184e..46833ae 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -366,8 +366,7 @@ static void xennet_tx_buf_gc(struct net_device *dev)
                                       "domain.\n");
                                BUG();
                        }
-                       gnttab_end_foreign_access_ref(
-                               np->grant_tx_ref[id], GNTMAP_readonly);
+                       gnttab_end_foreign_access_ref(np->grant_tx_ref[id]);
                        gnttab_release_grant_reference(
                                &np->gref_tx_head, np->grant_tx_ref[id]);
                        np->grant_tx_ref[id] = GRANT_INVALID_REF;
@@ -425,7 +424,7 @@ static void xennet_make_frags(struct sk_buff *skb, struct 
net_device *dev,
 
                mfn = virt_to_mfn(data);
                gnttab_grant_foreign_access_ref(ref, np->xbdev->otherend_id,
-                                               mfn, GNTMAP_readonly);
+                                               mfn, GTF_readonly);
 
                tx->gref = np->grant_tx_ref[id] = ref;
                tx->offset = offset;
@@ -448,7 +447,7 @@ static void xennet_make_frags(struct sk_buff *skb, struct 
net_device *dev,
 
                mfn = pfn_to_mfn(page_to_pfn(frag->page));
                gnttab_grant_foreign_access_ref(ref, np->xbdev->otherend_id,
-                                               mfn, GNTMAP_readonly);
+                                               mfn, GTF_readonly);
 
                tx->gref = np->grant_tx_ref[id] = ref;
                tx->offset = frag->page_offset;
@@ -503,7 +502,7 @@ static int xennet_start_xmit(struct sk_buff *skb, struct 
net_device *dev)
        BUG_ON((signed short)ref < 0);
        mfn = virt_to_mfn(data);
        gnttab_grant_foreign_access_ref(
-               ref, np->xbdev->otherend_id, mfn, GNTMAP_readonly);
+               ref, np->xbdev->otherend_id, mfn, GTF_readonly);
        tx->gref = np->grant_tx_ref[id] = ref;
        tx->offset = offset;
        tx->size = len;
@@ -675,7 +674,7 @@ static int xennet_get_responses(struct netfront_info *np,
                        goto next;
                }
 
-               ret = gnttab_end_foreign_access_ref(ref, 0);
+               ret = gnttab_end_foreign_access_ref(ref);
                BUG_ON(!ret);
 
                gnttab_release_grant_reference(&np->gref_rx_head, ref);
@@ -1010,8 +1009,7 @@ static void xennet_release_tx_bufs(struct netfront_info 
*np)
                        continue;
 
                skb = np->tx_skbs[i].skb;
-               gnttab_end_foreign_access_ref(np->grant_tx_ref[i],
-                                             GNTMAP_readonly);
+               gnttab_end_foreign_access_ref(np->grant_tx_ref[i]);
                gnttab_release_grant_reference(&np->gref_tx_head,
                                               np->grant_tx_ref[i]);
                np->grant_tx_ref[i] = GRANT_INVALID_REF;
@@ -1241,7 +1239,7 @@ static void xennet_end_access(int ref, void *page)
 {
        /* This frees the page as a side-effect */
        if (ref != GRANT_INVALID_REF)
-               gnttab_end_foreign_access(ref, 0, (unsigned long)page);
+               gnttab_end_foreign_access(ref, (unsigned long)page);
 }
 
 static void xennet_disconnect_backend(struct netfront_info *info)
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index 58996c9..385187e 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -159,15 +159,14 @@ static void update_grant_entry(grant_ref_t ref, domid_t 
domid,
  * Public grant-issuing interface functions
  */
 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
-                                    unsigned long frame, int readonly)
+                                    unsigned long frame, int flags)
 {
-       update_grant_entry(ref, domid, frame,
-                          GTF_permit_access | (readonly ? GTF_readonly : 0));
+       update_grant_entry(ref, domid, frame, GTF_permit_access | flags);
 }
 EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref);
 
 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
-                               int readonly)
+                               int flags)
 {
        int ref;
 
@@ -175,7 +174,7 @@ int gnttab_grant_foreign_access(domid_t domid, unsigned 
long frame,
        if (unlikely(ref < 0))
                return -ENOSPC;
 
-       gnttab_grant_foreign_access_ref(ref, domid, frame, readonly);
+       gnttab_grant_foreign_access_ref(ref, domid, frame, flags);
 
        return ref;
 }
@@ -191,7 +190,7 @@ int gnttab_query_foreign_access(grant_ref_t ref)
 }
 EXPORT_SYMBOL_GPL(gnttab_query_foreign_access);
 
-int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
+int gnttab_end_foreign_access_ref(grant_ref_t ref)
 {
        u16 flags, nflags;
 
@@ -208,10 +207,9 @@ int gnttab_end_foreign_access_ref(grant_ref_t ref, int 
readonly)
 }
 EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref);
 
-void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
-                              unsigned long page)
+void gnttab_end_foreign_access(grant_ref_t ref, unsigned long page)
 {
-       if (gnttab_end_foreign_access_ref(ref, readonly)) {
+       if (gnttab_end_foreign_access_ref(ref)) {
                put_free_entry(ref);
                if (page != 0)
                        free_page(page);
diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h
index b89ee8a..8493a83 100644
--- a/include/xen/grant_table.h
+++ b/include/xen/grant_table.h
@@ -63,14 +63,14 @@ int gnttab_suspend(void);
 int gnttab_resume(void);
 
 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
-                               int readonly);
+                               int flags);
 
 /*
  * End access through the given grant reference, iff the grant entry is no
  * longer in use.  Return 1 if the grant entry was freed, 0 if it is still in
  * use.
  */
-int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly);
+int gnttab_end_foreign_access_ref(grant_ref_t ref);
 
 /*
  * Eventually end access through the given grant reference, and once that
@@ -78,8 +78,7 @@ int gnttab_end_foreign_access_ref(grant_ref_t ref, int 
readonly);
  * immediately iff the grant entry is not in use, otherwise it will happen
  * some time later.  page may be 0, in which case no freeing will occur.
  */
-void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
-                              unsigned long page);
+void gnttab_end_foreign_access(grant_ref_t ref, unsigned long page);
 
 int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn);
 
-- 
1.5.6.5


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel