[PATCH XEN v7 11/29] tools: Remove xc_map_foreign_batch

[Ian Campbell <ian.campbell@citrix.com>]

It can trivially be replaced by xc_map_foreign_pages which is the
interface I want to move to going forward (by standardising on _bulk
but handling err=NULL as _pages does).

The callers of _batch are checking a mixture of a NULL return or
looking to see if the top nibble of the (usually sole) mfn they pass
has been modified to be non-zero to detect errors. _pages never
modifies the mfn it was given (it's const) and returns NULL on
failure, so adjust the error handling where necessary. Some callers
use a copy of the mfn array, for reuse on failure with _batch, which
is no longer necessary as _pages doesn't modify the array, however I
haven't cleaned that up here.

This reduces the twist maze of xc_map_foreign_* by one, which will be
useful when trying to come up with an underlying stable interface.

NetBSD and Solaris implemented xc_map_foreign_bulk in terms of
xc_map_foreign_batch via a compat layer, so xc_map_foreign_batch
becomes an internal osdep for them.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Cc: George Dunlap <george.dunlap@eu.citrix.com>
---
v7: Don't mention new ports implementing _bulk, which is confusing and
    will be obsolete a couple of patches later.
v6: Switch to xc_map_foreign_pages not xc_map_foreign_bulk, since the
    former has more similar error handling semantics to the current
    usage.

    Dropped acks.
---
 tools/libxc/include/xenctrl.h   | 10 -------
 tools/libxc/xc_foreign_memory.c |  4 ++-
 tools/libxc/xc_linux_osdep.c    | 59 +++--------------------------------------
 tools/libxc/xc_minios.c         | 22 ---------------
 tools/libxc/xc_netbsd.c         | 10 +++----
 tools/libxc/xc_solaris.c        |  6 ++---
 tools/libxc/xc_vm_event.c       | 18 ++++++++++---
 tools/xenmon/xenbaked.c         | 12 ++++++++-
 tools/xenpaging/xenpaging.c     | 14 +++++-----
 tools/xentrace/xentrace.c       |  3 ++-
 10 files changed, 48 insertions(+), 110 deletions(-)

diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index 78400d3..cb41c07 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -1387,16 +1387,6 @@ void *xc_map_foreign_pages(xc_interface *xch, uint32_t dom, int prot,
                            const xen_pfn_t *arr, int num );
 
 /**
- * DEPRECATED - use xc_map_foreign_bulk() instead.
- *
- * Like xc_map_foreign_pages(), except it can succeeed partially.
- * When a page cannot be mapped, its PFN in @arr is or'ed with
- * 0xF0000000 to indicate the error.
- */
-void *xc_map_foreign_batch(xc_interface *xch, uint32_t dom, int prot,
-                           xen_pfn_t *arr, int num );
-
-/**
  * Like xc_map_foreign_pages(), except it can succeed partially.
  * When a page cannot be mapped, its respective field in @err is
  * set to the corresponding errno value.
diff --git a/tools/libxc/xc_foreign_memory.c b/tools/libxc/xc_foreign_memory.c
index b205bca..2413e75 100644
--- a/tools/libxc/xc_foreign_memory.c
+++ b/tools/libxc/xc_foreign_memory.c
@@ -55,6 +55,8 @@ void *xc_map_foreign_pages(xc_interface *xch, uint32_t dom, int prot,
  * just implement xc_map_foreign_bulk.
  */
 #if defined(__NetBSD__) || defined(__sun__)
+void *osdep_map_foreign_batch(xc_interface *xch, uint32_t dom, int prot,
+                              xen_pfn_t *arr, int num );
 void *xc_map_foreign_bulk(xc_interface *xch,
                           uint32_t dom, int prot,
                           const xen_pfn_t *arr, int *err, unsigned int num)
@@ -75,7 +77,7 @@ void *xc_map_foreign_bulk(xc_interface *xch,
     }
 
     memcpy(pfn, arr, num * sizeof(*arr));
-    ret = xc_map_foreign_batch(xch, dom, prot, pfn, num);
+    ret = osdep_map_foreign_batch(xch, dom, prot, pfn, num);
 
     if (ret) {
         for (i = 0; i < num; ++i)
diff --git a/tools/libxc/xc_linux_osdep.c b/tools/libxc/xc_linux_osdep.c
index e68c495..39c88ce 100644
--- a/tools/libxc/xc_linux_osdep.c
+++ b/tools/libxc/xc_linux_osdep.c
@@ -91,8 +91,8 @@ int osdep_privcmd_close(xc_interface *xch)
     return close(fd);
 }
 
-static int xc_map_foreign_batch_single(int fd, uint32_t dom,
-                                       xen_pfn_t *mfn, unsigned long addr)
+static int map_foreign_batch_single(int fd, uint32_t dom,
+                                    xen_pfn_t *mfn, unsigned long addr)
 {
     privcmd_mmapbatch_t ioctlx;
     int rc;
@@ -113,59 +113,6 @@ static int xc_map_foreign_batch_single(int fd, uint32_t dom,
     return rc;
 }
 
-void *xc_map_foreign_batch(xc_interface *xch,
-                           uint32_t dom, int prot,
-                           xen_pfn_t *arr, int num)
-{
-    int fd = xch->privcmdfd;
-    privcmd_mmapbatch_t ioctlx;
-    void *addr;
-    int rc;
-
-    addr = mmap(NULL, num << XC_PAGE_SHIFT, prot, MAP_SHARED, fd, 0);
-    if ( addr == MAP_FAILED )
-    {
-        PERROR("xc_map_foreign_batch: mmap failed");
-        return NULL;
-    }
-
-    ioctlx.num = num;
-    ioctlx.dom = dom;
-    ioctlx.addr = (unsigned long)addr;
-    ioctlx.arr = arr;
-
-    rc = ioctl(fd, IOCTL_PRIVCMD_MMAPBATCH, &ioctlx);
-    if ( (rc < 0) && (errno == ENOENT) )
-    {
-        int i;
-
-        for ( i = 0; i < num; i++ )
-        {
-            if ( (arr[i] & PRIVCMD_MMAPBATCH_MFN_ERROR) ==
-                           PRIVCMD_MMAPBATCH_PAGED_ERROR )
-            {
-                unsigned long paged_addr = (unsigned long)addr + (i << XC_PAGE_SHIFT);
-                rc = xc_map_foreign_batch_single(fd, dom, &arr[i],
-                                                 paged_addr);
-                if ( rc < 0 )
-                    goto out;
-            }
-        }
-    }
-
- out:
-    if ( rc < 0 )
-    {
-        int saved_errno = errno;
-        PERROR("xc_map_foreign_batch: ioctl failed");
-        (void)munmap(addr, num << XC_PAGE_SHIFT);
-        errno = saved_errno;
-        return NULL;
-    }
-
-    return addr;
-}
-
 /*
  * Retry mmap of all paged gfns in batches
  * retuns < 0 on fatal error
@@ -305,7 +252,7 @@ void *xc_map_foreign_bulk(xc_interface *xch,
                     err[i] = rc ?: -EINVAL;
                     continue;
                 }
-                rc = xc_map_foreign_batch_single(fd, dom, pfn + i,
+                rc = map_foreign_batch_single(fd, dom, pfn + i,
                         (unsigned long)addr + ((unsigned long)i<<XC_PAGE_SHIFT));
                 if ( rc < 0 )
                 {
diff --git a/tools/libxc/xc_minios.c b/tools/libxc/xc_minios.c
index e3c8241..3ea3124 100644
--- a/tools/libxc/xc_minios.c
+++ b/tools/libxc/xc_minios.c
@@ -73,28 +73,6 @@ void *xc_map_foreign_bulk(xc_interface *xch,
     return map_frames_ex(arr, num, 1, 0, 1, dom, err, pt_prot);
 }
 
-void *xc_map_foreign_batch(xc_interface *xch,
-                           uint32_t dom, int prot,
-                           xen_pfn_t *arr, int num)
-{
-    unsigned long pt_prot = 0;
-    int err[num];
-    int i;
-    unsigned long addr;
-
-    if (prot & PROT_READ)
-	pt_prot = L1_PROT_RO;
-    if (prot & PROT_WRITE)
-	pt_prot = L1_PROT;
-
-    addr = (unsigned long) map_frames_ex(arr, num, 1, 0, 1, dom, err, pt_prot);
-    for (i = 0; i < num; i++) {
-        if (err[i])
-            arr[i] |= 0xF0000000;
-    }
-    return (void *) addr;
-}
-
 void *xc_map_foreign_range(xc_interface *xch,
                            uint32_t dom,
                            int size, int prot,
diff --git a/tools/libxc/xc_netbsd.c b/tools/libxc/xc_netbsd.c
index d7f7f31..6a7ff9f 100644
--- a/tools/libxc/xc_netbsd.c
+++ b/tools/libxc/xc_netbsd.c
@@ -67,16 +67,16 @@ int osdep_privcmd_close(xc_interface *xch)
     return close(fd);
 }
 
-void *xc_map_foreign_batch(xc_interface *xch,
-                           uint32_t dom, int prot,
-                           xen_pfn_t *arr, int num)
+void *osdep_map_foreign_batch(xc_interface *xch,
+                              uint32_t dom, int prot,
+                              xen_pfn_t *arr, int num)
 {
     int fd = xch->privcmdfd;
     privcmd_mmapbatch_t ioctlx;
     void *addr;
     addr = mmap(NULL, num*XC_PAGE_SIZE, prot, MAP_ANON | MAP_SHARED, -1, 0);
     if ( addr == MAP_FAILED ) {
-        PERROR("xc_map_foreign_batch: mmap failed");
+        PERROR("osdep_map_foreign_batch: mmap failed");
         return NULL;
     }
 
@@ -87,7 +87,7 @@ void *xc_map_foreign_batch(xc_interface *xch,
     if ( ioctl(fd, IOCTL_PRIVCMD_MMAPBATCH, &ioctlx) < 0 )
     {
         int saved_errno = errno;
-        PERROR("xc_map_foreign_batch: ioctl failed");
+        PERROR("osdep_map_foreign_batch: ioctl failed");
         (void)munmap(addr, num*XC_PAGE_SIZE);
         errno = saved_errno;
         return NULL;
diff --git a/tools/libxc/xc_solaris.c b/tools/libxc/xc_solaris.c
index 5e72dee..2df7a06 100644
--- a/tools/libxc/xc_solaris.c
+++ b/tools/libxc/xc_solaris.c
@@ -67,9 +67,9 @@ int osdep_privcmd_close(xc_interface *xch)
     return close(fd);
 }
 
-void *xc_map_foreign_batch(xc_interface *xch,
-                          uint32_t dom, int prot,
-                          xen_pfn_t *arr, int num)
+void *osdep_map_foreign_batch(xc_interface *xch,
+                              uint32_t dom, int prot,
+                              xen_pfn_t *arr, int num)
 {
     int fd = xch->privcmdfd;
     privcmd_mmapbatch_t ioctlx;
diff --git a/tools/libxc/xc_vm_event.c b/tools/libxc/xc_vm_event.c
index 2fef96a..d2d99e4 100644
--- a/tools/libxc/xc_vm_event.c
+++ b/tools/libxc/xc_vm_event.c
@@ -72,9 +72,9 @@ void *xc_vm_event_enable(xc_interface *xch, domid_t domain_id, int param,
 
     ring_pfn = pfn;
     mmap_pfn = pfn;
-    ring_page = xc_map_foreign_batch(xch, domain_id, PROT_READ | PROT_WRITE,
+    ring_page = xc_map_foreign_pages(xch, domain_id, PROT_READ | PROT_WRITE,
                                      &mmap_pfn, 1);
-    if ( mmap_pfn & XEN_DOMCTL_PFINFO_XTAB )
+    if ( !ring_page )
     {
         /* Map failed, populate ring page */
         rc1 = xc_domain_populate_physmap_exact(xch, domain_id, 1, 0, 0,
@@ -86,9 +86,9 @@ void *xc_vm_event_enable(xc_interface *xch, domid_t domain_id, int param,
         }
 
         mmap_pfn = ring_pfn;
-        ring_page = xc_map_foreign_batch(xch, domain_id, PROT_READ | PROT_WRITE,
+        ring_page = xc_map_foreign_pages(xch, domain_id, PROT_READ | PROT_WRITE,
                                          &mmap_pfn, 1);
-        if ( mmap_pfn & XEN_DOMCTL_PFINFO_XTAB )
+        if ( !ring_page )
         {
             PERROR("Could not map the ring page\n");
             goto out;
@@ -156,3 +156,13 @@ void *xc_vm_event_enable(xc_interface *xch, domid_t domain_id, int param,
 
     return ring_page;
 }
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/xenmon/xenbaked.c b/tools/xenmon/xenbaked.c
index e4602ef..da46126 100644
--- a/tools/xenmon/xenbaked.c
+++ b/tools/xenmon/xenbaked.c
@@ -411,7 +411,7 @@ static struct t_struct *map_tbufs(unsigned long tbufs_mfn, unsigned int num,
         for ( j=0; j<tbufs.t_info->tbuf_size; j++)
             pfn_list[j] = (xen_pfn_t)mfn_list[j];
 
-        tbufs.meta[i] = xc_map_foreign_batch(xc_handle, DOMID_XEN,
+        tbufs.meta[i] = xc_map_foreign_pages(xc_handle, DOMID_XEN,
                                              PROT_READ | PROT_WRITE,
                                              pfn_list,
                                              tbufs.t_info->tbuf_size);
@@ -1175,3 +1175,13 @@ static int process_record(int cpu, struct t_rec *r)
 
     return 4 + (r->cycles_included ? 8 : 0) + (r->extra_u32 * 4);
 }
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/xenpaging/xenpaging.c b/tools/xenpaging/xenpaging.c
index df99c6a..c4bc713 100644
--- a/tools/xenpaging/xenpaging.c
+++ b/tools/xenpaging/xenpaging.c
@@ -342,9 +342,9 @@ static struct xenpaging *xenpaging_init(int argc, char *argv[])
                         HVM_PARAM_PAGING_RING_PFN, &ring_pfn);
     mmap_pfn = ring_pfn;
     paging->vm_event.ring_page = 
-        xc_map_foreign_batch(xch, paging->vm_event.domain_id, 
-                                PROT_READ | PROT_WRITE, &mmap_pfn, 1);
-    if ( mmap_pfn & XEN_DOMCTL_PFINFO_XTAB )
+        xc_map_foreign_pages(xch, paging->vm_event.domain_id,
+                             PROT_READ | PROT_WRITE, &mmap_pfn, 1);
+    if ( !paging->vm_event.ring_page )
     {
         /* Map failed, populate ring page */
         rc = xc_domain_populate_physmap_exact(paging->xc_handle, 
@@ -356,11 +356,11 @@ static struct xenpaging *xenpaging_init(int argc, char *argv[])
             goto err;
         }
 
-        mmap_pfn = ring_pfn;
         paging->vm_event.ring_page = 
-            xc_map_foreign_batch(xch, paging->vm_event.domain_id, 
-                                    PROT_READ | PROT_WRITE, &mmap_pfn, 1);
-        if ( mmap_pfn & XEN_DOMCTL_PFINFO_XTAB )
+            xc_map_foreign_pages(xch, paging->vm_event.domain_id,
+                                 PROT_READ | PROT_WRITE,
+                                 &mmap_pfn, 1);
+        if ( !paging->vm_event.ring_page )
         {
             PERROR("Could not map the ring page\n");
             goto err;
diff --git a/tools/xentrace/xentrace.c b/tools/xentrace/xentrace.c
index c970d42..6cbe0ac 100644
--- a/tools/xentrace/xentrace.c
+++ b/tools/xentrace/xentrace.c
@@ -508,7 +508,7 @@ static struct t_struct *map_tbufs(unsigned long tbufs_mfn, unsigned int num,
         for ( j=0; j<tbufs.t_info->tbuf_size; j++)
             pfn_list[j] = (xen_pfn_t)mfn_list[j];
 
-        tbufs.meta[i] = xc_map_foreign_batch(xc_handle, DOMID_XEN,
+        tbufs.meta[i] = xc_map_foreign_pages(xc_handle, DOMID_XEN,
                                              PROT_READ | PROT_WRITE,
                                              pfn_list,
                                              tbufs.t_info->tbuf_size);
@@ -1221,6 +1221,7 @@ int main(int argc, char **argv)
 
     return ret;
 }
+
 /*
  * Local variables:
  * mode: C
-- 
2.1.4