[PATCH V5 03/12] xen/mem_paging: Convert mem_event_op to mem_paging_op

[Tamas K Lengyel <tamas.lengyel@zentific.com>]

The only use-case of the mem_event_op structure had been in mem_paging,
thus renaming the structure mem_paging_op and relocating its associated
functions clarifies its actual usage.

Signed-off-by: Tamas K Lengyel <tamas.lengyel@zentific.com>
Acked-by: Tim Deegan <tim@xen.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
---
v5: Style fixes
v4: Style fixes
v3: Style fixes
---
 tools/libxc/xc_mem_event.c       | 16 ----------------
 tools/libxc/xc_mem_paging.c      | 26 ++++++++++++++++++--------
 tools/libxc/xc_private.h         |  3 ---
 xen/arch/x86/mm/mem_paging.c     | 32 +++++++++++++-------------------
 xen/arch/x86/x86_64/compat/mm.c  | 10 ++++++----
 xen/arch/x86/x86_64/mm.c         |  8 ++++----
 xen/common/mem_event.c           |  4 ++--
 xen/include/asm-x86/mem_paging.h |  2 +-
 xen/include/public/memory.h      |  9 ++++-----
 9 files changed, 48 insertions(+), 62 deletions(-)

diff --git a/tools/libxc/xc_mem_event.c b/tools/libxc/xc_mem_event.c
index ee25cdd..487fcee 100644
--- a/tools/libxc/xc_mem_event.c
+++ b/tools/libxc/xc_mem_event.c
@@ -40,22 +40,6 @@ int xc_mem_event_control(xc_interface *xch, domid_t domain_id, unsigned int op,
     return rc;
 }
 
-int xc_mem_event_memop(xc_interface *xch, domid_t domain_id, 
-                        unsigned int op, unsigned int mode,
-                        uint32_t gfn, void *buffer)
-{
-    xen_mem_event_op_t meo;
-
-    memset(&meo, 0, sizeof(meo));
-
-    meo.op      = op;
-    meo.domain  = domain_id;
-    meo.gfn     = gfn;
-    meo.buffer  = (unsigned long) buffer;
-
-    return do_memory_op(xch, mode, &meo, sizeof(meo));
-}
-
 void *xc_mem_event_enable(xc_interface *xch, domid_t domain_id, int param,
                           uint32_t *port, int enable_introspection)
 {
diff --git a/tools/libxc/xc_mem_paging.c b/tools/libxc/xc_mem_paging.c
index 5194423..049aff4 100644
--- a/tools/libxc/xc_mem_paging.c
+++ b/tools/libxc/xc_mem_paging.c
@@ -23,6 +23,20 @@
 
 #include "xc_private.h"
 
+static int xc_mem_paging_memop(xc_interface *xch, domid_t domain_id,
+                               unsigned int op, uint32_t gfn, void *buffer)
+{
+    xen_mem_paging_op_t mpo;
+
+    memset(&mpo, 0, sizeof(mpo));
+
+    mpo.op      = op;
+    mpo.domain  = domain_id;
+    mpo.gfn     = gfn;
+    mpo.buffer  = (unsigned long) buffer;
+
+    return do_memory_op(xch, XENMEM_paging_op, &mpo, sizeof(mpo));
+}
 
 int xc_mem_paging_enable(xc_interface *xch, domid_t domain_id,
                          uint32_t *port)
@@ -49,25 +63,22 @@ int xc_mem_paging_disable(xc_interface *xch, domid_t domain_id)
 
 int xc_mem_paging_nominate(xc_interface *xch, domid_t domain_id, unsigned long gfn)
 {
-    return xc_mem_event_memop(xch, domain_id,
+    return xc_mem_paging_memop(xch, domain_id,
                                 XENMEM_paging_op_nominate,
-                                XENMEM_paging_op,
                                 gfn, NULL);
 }
 
 int xc_mem_paging_evict(xc_interface *xch, domid_t domain_id, unsigned long gfn)
 {
-    return xc_mem_event_memop(xch, domain_id,
+    return xc_mem_paging_memop(xch, domain_id,
                                 XENMEM_paging_op_evict,
-                                XENMEM_paging_op,
                                 gfn, NULL);
 }
 
 int xc_mem_paging_prep(xc_interface *xch, domid_t domain_id, unsigned long gfn)
 {
-    return xc_mem_event_memop(xch, domain_id,
+    return xc_mem_paging_memop(xch, domain_id,
                                 XENMEM_paging_op_prep,
-                                XENMEM_paging_op,
                                 gfn, NULL);
 }
 
@@ -87,9 +98,8 @@ int xc_mem_paging_load(xc_interface *xch, domid_t domain_id,
     if ( mlock(buffer, XC_PAGE_SIZE) )
         return -1;
         
-    rc = xc_mem_event_memop(xch, domain_id,
+    rc = xc_mem_paging_memop(xch, domain_id,
                                 XENMEM_paging_op_prep,
-                                XENMEM_paging_op,
                                 gfn, buffer);
 
     old_errno = errno;
diff --git a/tools/libxc/xc_private.h b/tools/libxc/xc_private.h
index bc021b8..f1f601c 100644
--- a/tools/libxc/xc_private.h
+++ b/tools/libxc/xc_private.h
@@ -425,9 +425,6 @@ int xc_ffs64(uint64_t x);
  */
 int xc_mem_event_control(xc_interface *xch, domid_t domain_id, unsigned int op,
                          unsigned int mode, uint32_t *port);
-int xc_mem_event_memop(xc_interface *xch, domid_t domain_id,
-                        unsigned int op, unsigned int mode,
-                        uint32_t gfn, void *buffer);
 /*
  * Enables mem_event and returns the mapped ring page indicated by param.
  * param can be HVM_PARAM_PAGING/ACCESS/SHARING_RING_PFN
diff --git a/xen/arch/x86/mm/mem_paging.c b/xen/arch/x86/mm/mem_paging.c
index 65f6a3d..87a7b72 100644
--- a/xen/arch/x86/mm/mem_paging.c
+++ b/xen/arch/x86/mm/mem_paging.c
@@ -25,38 +25,32 @@
 #include <xen/mem_event.h>
 
 
-int mem_paging_memop(struct domain *d, xen_mem_event_op_t *mec)
+int mem_paging_memop(struct domain *d, xen_mem_paging_op_t *mpo)
 {
+    int rc = -ENODEV;
     if ( unlikely(!d->mem_event->paging.ring_page) )
-        return -ENODEV;
+        return rc;
 
-    switch( mec->op )
+    switch( mpo->op )
     {
     case XENMEM_paging_op_nominate:
-    {
-        unsigned long gfn = mec->gfn;
-        return p2m_mem_paging_nominate(d, gfn);
-    }
-    break;
+        rc = p2m_mem_paging_nominate(d, mpo->gfn);
+        break;
 
     case XENMEM_paging_op_evict:
-    {
-        unsigned long gfn = mec->gfn;
-        return p2m_mem_paging_evict(d, gfn);
-    }
-    break;
+        rc = p2m_mem_paging_evict(d, mpo->gfn);
+        break;
 
     case XENMEM_paging_op_prep:
-    {
-        unsigned long gfn = mec->gfn;
-        return p2m_mem_paging_prep(d, gfn, mec->buffer);
-    }
-    break;
+        rc = p2m_mem_paging_prep(d, mpo->gfn, mpo->buffer);
+        break;
 
     default:
-        return -ENOSYS;
+        rc = -ENOSYS;
         break;
     }
+
+    return rc;
 }
 
 
diff --git a/xen/arch/x86/x86_64/compat/mm.c b/xen/arch/x86/x86_64/compat/mm.c
index f90f611..96cec31 100644
--- a/xen/arch/x86/x86_64/compat/mm.c
+++ b/xen/arch/x86/x86_64/compat/mm.c
@@ -188,11 +188,12 @@ int compat_arch_memory_op(unsigned long cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
 
     case XENMEM_paging_op:
     {
-        xen_mem_event_op_t meo;
-        if ( copy_from_guest(&meo, arg, 1) )
+        xen_mem_paging_op_t mpo;
+
+        if ( copy_from_guest(&mpo, arg, 1) )
             return -EFAULT;
-        rc = do_mem_event_op(cmd, meo.domain, &meo);
-        if ( !rc && __copy_to_guest(arg, &meo, 1) )
+        rc = do_mem_event_op(cmd, mpo.domain, &mpo);
+        if ( !rc && __copy_to_guest(arg, &mpo, 1) )
             return -EFAULT;
         break;
     }
@@ -200,6 +201,7 @@ int compat_arch_memory_op(unsigned long cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
     case XENMEM_sharing_op:
     {
         xen_mem_sharing_op_t mso;
+
         if ( copy_from_guest(&mso, arg, 1) )
             return -EFAULT;
         if ( mso.op == XENMEM_sharing_op_audit )
diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
index d631aee..2fa1f67 100644
--- a/xen/arch/x86/x86_64/mm.c
+++ b/xen/arch/x86/x86_64/mm.c
@@ -985,11 +985,11 @@ long subarch_memory_op(unsigned long cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
 
     case XENMEM_paging_op:
     {
-        xen_mem_event_op_t meo;
-        if ( copy_from_guest(&meo, arg, 1) )
+        xen_mem_paging_op_t mpo;
+        if ( copy_from_guest(&mpo, arg, 1) )
             return -EFAULT;
-        rc = do_mem_event_op(cmd, meo.domain, &meo);
-        if ( !rc && __copy_to_guest(arg, &meo, 1) )
+        rc = do_mem_event_op(cmd, mpo.domain, &mpo);
+        if ( !rc && __copy_to_guest(arg, &mpo, 1) )
             return -EFAULT;
         break;
     }
diff --git a/xen/common/mem_event.c b/xen/common/mem_event.c
index b96d9fb..ae60c10 100644
--- a/xen/common/mem_event.c
+++ b/xen/common/mem_event.c
@@ -475,12 +475,12 @@ int do_mem_event_op(int op, uint32_t domain, void *arg)
     {
 #ifdef HAS_MEM_PAGING
         case XENMEM_paging_op:
-            ret = mem_paging_memop(d, (xen_mem_event_op_t *) arg);
+            ret = mem_paging_memop(d, arg);
             break;
 #endif
 #ifdef HAS_MEM_SHARING
         case XENMEM_sharing_op:
-            ret = mem_sharing_memop(d, (xen_mem_sharing_op_t *) arg);
+            ret = mem_sharing_memop(d, arg);
             break;
 #endif
         default:
diff --git a/xen/include/asm-x86/mem_paging.h b/xen/include/asm-x86/mem_paging.h
index 6b7a1fe..92ed2fa 100644
--- a/xen/include/asm-x86/mem_paging.h
+++ b/xen/include/asm-x86/mem_paging.h
@@ -21,7 +21,7 @@
  */
 
 
-int mem_paging_memop(struct domain *d, xen_mem_event_op_t *meo);
+int mem_paging_memop(struct domain *d, xen_mem_paging_op_t *meo);
 
 
 /*
diff --git a/xen/include/public/memory.h b/xen/include/public/memory.h
index 2ef1728..9c41f5d 100644
--- a/xen/include/public/memory.h
+++ b/xen/include/public/memory.h
@@ -372,10 +372,9 @@ typedef struct xen_pod_target xen_pod_target_t;
 #define XENMEM_paging_op_evict              1
 #define XENMEM_paging_op_prep               2
 
-struct xen_mem_event_op {
-    uint8_t     op;         /* XENMEM_*_op_* */
+struct xen_mem_paging_op {
+    uint8_t     op;         /* XENMEM_paging_op_* */
     domid_t     domain;
-    
 
     /* PAGING_PREP IN: buffer to immediately fill page in */
     uint64_aligned_t    buffer;
@@ -383,8 +382,8 @@ struct xen_mem_event_op {
     uint32_t    gfn;           /* IN:  gfn of page being operated on */
     uint32_t    _pad;
 };
-typedef struct xen_mem_event_op xen_mem_event_op_t;
-DEFINE_XEN_GUEST_HANDLE(xen_mem_event_op_t);
+typedef struct xen_mem_paging_op xen_mem_paging_op_t;
+DEFINE_XEN_GUEST_HANDLE(xen_mem_paging_op_t);
 
 #define XENMEM_access_op                    21
 #define XENMEM_access_op_resume             0
-- 
2.1.4