WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-changelog

[Xen-changelog] [xen-unstable] minios: grant table map (gntdev) for mini

To: xen-changelog@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-changelog] [xen-unstable] minios: grant table map (gntdev) for minios
From: Xen patchbot-unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>
Date: Thu, 24 Jul 2008 13:50:12 -0700
Delivery-date: Thu, 24 Jul 2008 13:50:16 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-changelog-request@lists.xensource.com?subject=help>
List-id: BK change log <xen-changelog.lists.xensource.com>
List-post: <mailto:xen-changelog@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-changelog>, <mailto:xen-changelog-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-changelog>, <mailto:xen-changelog-request@lists.xensource.com?subject=unsubscribe>
Reply-to: xen-devel@xxxxxxxxxxxxxxxxxxx
Sender: xen-changelog-bounces@xxxxxxxxxxxxxxxxxxx
# HG changeset patch
# User Keir Fraser <keir.fraser@xxxxxxxxxx>
# Date 1216905267 -3600
# Node ID 379dd201c36c294fbf41897619cbdd7d1823be38
# Parent  707569df20e1680b803e58b2e4a4ee6d5a98824e
minios: grant table map (gntdev) for minios

I've implemented a grant map for mini-os to support the xc_gnttab_*()
functions, the equivalent of gntdev in linux. This is useful for my
work in putting xenstored in a stub domain.

Signed-off-by: Diego Ongaro <diego.ongaro@xxxxxxxxxx>
---
 extras/mini-os/gntmap.c         |  250 ++++++++++++++++++++++++++++++++++++++++
 extras/mini-os/include/gntmap.h |   35 +++++
 extras/mini-os/include/lib.h    |    3 
 extras/mini-os/lib/sys.c        |    3 
 extras/mini-os/minios.mk        |    1 
 tools/libxc/xc_minios.c         |   71 +++++++++++
 6 files changed, 363 insertions(+)

diff -r 707569df20e1 -r 379dd201c36c extras/mini-os/gntmap.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/extras/mini-os/gntmap.c   Thu Jul 24 14:14:27 2008 +0100
@@ -0,0 +1,250 @@
+/*
+ * Manages grant mappings from other domains.
+ *
+ * Diego Ongaro <diego.ongaro@xxxxxxxxxx>, July 2008
+ *
+ * Files of type FTYPE_GNTMAP contain a gntmap, which is an array of
+ * (host address, grant handle) pairs. Grant handles come from a hypervisor map
+ * operation and are needed for the corresponding unmap.
+ *
+ * This is a rather naive implementation in terms of performance. If we start
+ * using it frequently, there's definitely some low-hanging fruit here.
+ *
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <os.h>
+#include <xmalloc.h>
+#include <errno.h>
+#include <xen/grant_table.h>
+#include <inttypes.h>
+#include "gntmap.h"
+
+#define DEFAULT_MAX_GRANTS 128
+
+struct gntmap_entry {
+    unsigned long host_addr;
+    grant_handle_t handle;
+};
+
+static inline int
+gntmap_entry_used(struct gntmap_entry *entry)
+{
+    return entry->host_addr != 0;
+}
+
+static struct gntmap_entry*
+gntmap_find_free_entry(struct gntmap *map)
+{
+    int i;
+
+    for (i = 0; i < map->nentries; i++) {
+        if (!gntmap_entry_used(&map->entries[i]))
+            return &map->entries[i];
+    }
+
+#ifdef GNTMAP_DEBUG
+    printk("gntmap_find_free_entry(map=%p): all %d entries full\n",
+           map, map->nentries);
+#endif
+    return NULL;
+}
+
+static struct gntmap_entry*
+gntmap_find_entry(struct gntmap *map, unsigned long addr)
+{
+    int i;
+
+    for (i = 0; i < map->nentries; i++) {
+        if (map->entries[i].host_addr == addr)
+            return &map->entries[i];
+    }
+    return NULL;
+}
+
+int
+gntmap_set_max_grants(struct gntmap *map, int count)
+{
+#ifdef GNTMAP_DEBUG
+    printk("gntmap_set_max_grants(map=%p, count=%d)\n", map, count);
+#endif
+
+    if (map->nentries != 0)
+        return -EBUSY;
+
+    map->entries = xmalloc_array(struct gntmap_entry, count);
+    if (map->entries == NULL)
+        return -ENOMEM;
+
+    memset(map->entries, 0, sizeof(struct gntmap_entry) * count);
+    map->nentries = count;
+    return 0;
+}
+
+static int
+_gntmap_map_grant_ref(struct gntmap_entry *entry, 
+                      unsigned long host_addr,
+                      uint32_t domid,
+                      uint32_t ref,
+                      int writable)
+{
+    struct gnttab_map_grant_ref op;
+    int rc;
+
+    op.ref = (grant_ref_t) ref;
+    op.dom = (domid_t) domid;
+    op.host_addr = (uint64_t) host_addr;
+    op.flags = GNTMAP_host_map;
+    if (!writable)
+        op.flags |= GNTMAP_readonly;
+
+    rc = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1);
+    if (rc != 0 || op.status != GNTST_okay) {
+        printk("GNTTABOP_map_grant_ref failed: "
+               "returned %d, status %d\n",
+               rc, op.status);
+        return rc != 0 ? rc : op.status;
+    }
+
+    entry->host_addr = host_addr;
+    entry->handle = op.handle;
+    return 0;
+}
+
+static int
+_gntmap_unmap_grant_ref(struct gntmap_entry *entry)
+{
+    struct gnttab_unmap_grant_ref op;
+    int rc;
+
+    op.host_addr    = (uint64_t) entry->host_addr;
+    op.handle       = entry->handle;
+
+    rc = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1);
+    if (rc != 0 || op.status != GNTST_okay) {
+        printk("GNTTABOP_unmap_grant_ref failed: "
+               "returned %d, status %d\n",
+               rc, op.status);
+        return rc != 0 ? rc : op.status;
+    }
+
+    entry->host_addr = 0;
+    return 0;
+}
+
+int
+gntmap_munmap(struct gntmap *map, unsigned long start_address, int count)
+{
+    int i, rc;
+    struct gntmap_entry *ent;
+
+#ifdef GNTMAP_DEBUG
+    printk("gntmap_munmap(map=%p, start_address=%lx, count=%d)\n",
+           map, start_address, count);
+#endif
+
+    for (i = 0; i < count; i++) {
+        ent = gntmap_find_entry(map, start_address + PAGE_SIZE * i);
+        if (ent == NULL) {
+            printk("gntmap: tried to munmap unknown page\n");
+            return -EINVAL;
+        }
+
+        rc = _gntmap_unmap_grant_ref(ent);
+        if (rc != 0)
+            return rc;
+    }
+
+    return 0;
+}
+
+void*
+gntmap_map_grant_refs(struct gntmap *map, 
+                      uint32_t count,
+                      uint32_t *domids,
+                      int domids_stride,
+                      uint32_t *refs,
+                      int writable)
+{
+    unsigned long addr;
+    struct gntmap_entry *ent;
+    int i;
+
+#ifdef GNTMAP_DEBUG
+    printk("gntmap_map_grant_refs(map=%p, count=%" PRIu32 ", "
+           "domids=%p [%" PRIu32 "...], domids_stride=%d, "
+           "refs=%p [%" PRIu32 "...], writable=%d)\n",
+           map, count, domids, domids[0], domids_stride,
+           refs, refs[0], writable);
+#endif
+
+    (void) gntmap_set_max_grants(map, DEFAULT_MAX_GRANTS);
+
+    addr = allocate_ondemand((unsigned long) count, 1);
+    if (addr == 0)
+        return NULL;
+
+    for (i = 0; i < count; i++) {
+        ent = gntmap_find_free_entry(map);
+        if (ent == NULL ||
+            _gntmap_map_grant_ref(ent,
+                                  addr + PAGE_SIZE * i,
+                                  domids[i * domids_stride],
+                                  refs[i],
+                                  writable) != 0) {
+
+            (void) gntmap_munmap(map, addr, i);
+            return NULL;
+        }
+    }
+
+    return (void*) addr;
+}
+
+void
+gntmap_init(struct gntmap *map)
+{
+#ifdef GNTMAP_DEBUG
+    printk("gntmap_init(map=%p)\n", map);
+#endif
+    map->nentries = 0;
+    map->entries = NULL;
+}
+
+void
+gntmap_fini(struct gntmap *map)
+{
+    struct gntmap_entry *ent;
+    int i;
+
+#ifdef GNTMAP_DEBUG
+    printk("gntmap_fini(map=%p)\n", map);
+#endif
+
+    for (i = 0; i < map->nentries; i++) {
+        ent = &map->entries[i];
+        if (gntmap_entry_used(ent))
+            (void) _gntmap_unmap_grant_ref(ent);
+    }
+
+    xfree(map->entries);
+    map->entries = NULL;
+    map->nentries = 0;
+}
diff -r 707569df20e1 -r 379dd201c36c extras/mini-os/include/gntmap.h
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/extras/mini-os/include/gntmap.h   Thu Jul 24 14:14:27 2008 +0100
@@ -0,0 +1,35 @@
+#ifndef __GNTMAP_H__
+#define __GNTMAP_H__
+
+#include <os.h>
+
+/*
+ * Please consider struct gntmap opaque. If instead you choose to disregard
+ * this message, I insist that you keep an eye out for raptors.
+ */
+struct gntmap {
+    int nentries;
+    struct gntmap_entry *entries;
+};
+
+int
+gntmap_set_max_grants(struct gntmap *map, int count);
+
+int
+gntmap_munmap(struct gntmap *map, unsigned long start_address, int count);
+
+void*
+gntmap_map_grant_refs(struct gntmap *map, 
+                      uint32_t count,
+                      uint32_t *domids,
+                      int domids_stride,
+                      uint32_t *refs,
+                      int writable);
+
+void
+gntmap_init(struct gntmap *map);
+
+void
+gntmap_fini(struct gntmap *map);
+
+#endif /* !__GNTMAP_H__ */
diff -r 707569df20e1 -r 379dd201c36c extras/mini-os/include/lib.h
--- a/extras/mini-os/include/lib.h      Thu Jul 24 14:12:46 2008 +0100
+++ b/extras/mini-os/include/lib.h      Thu Jul 24 14:14:27 2008 +0100
@@ -59,6 +59,7 @@
 #include <stddef.h>
 #include <xen/xen.h>
 #include <xen/event_channel.h>
+#include "gntmap.h"
 
 #ifdef HAVE_LIBC
 #include <stdio.h>
@@ -138,6 +139,7 @@ enum fd_type {
     FTYPE_XENBUS,
     FTYPE_XC,
     FTYPE_EVTCHN,
+    FTYPE_GNTMAP,
     FTYPE_SOCKET,
     FTYPE_TAP,
     FTYPE_BLK,
@@ -168,6 +170,7 @@ extern struct file {
                 int bound;
             } ports[MAX_EVTCHN_PORTS];
        } evtchn;
+       struct gntmap gntmap;
        struct {
            struct netfront_dev *dev;
        } tap;
diff -r 707569df20e1 -r 379dd201c36c extras/mini-os/lib/sys.c
--- a/extras/mini-os/lib/sys.c  Thu Jul 24 14:12:46 2008 +0100
+++ b/extras/mini-os/lib/sys.c  Thu Jul 24 14:14:27 2008 +0100
@@ -401,6 +401,9 @@ int close(int fd)
        case FTYPE_EVTCHN:
             xc_evtchn_close(fd);
             return 0;
+       case FTYPE_GNTMAP:
+           xc_gnttab_close(fd);
+           return 0;
        case FTYPE_TAP:
            shutdown_netfront(files[fd].tap.dev);
            files[fd].type = FTYPE_NONE;
diff -r 707569df20e1 -r 379dd201c36c extras/mini-os/minios.mk
--- a/extras/mini-os/minios.mk  Thu Jul 24 14:12:46 2008 +0100
+++ b/extras/mini-os/minios.mk  Thu Jul 24 14:14:27 2008 +0100
@@ -21,6 +21,7 @@ DEF_CFLAGS += -g
 #DEF_CFLAGS += -DFS_DEBUG
 #DEF_CFLAGS += -DLIBC_DEBUG
 DEF_CFLAGS += -DGNT_DEBUG
+DEF_CFLAGS += -DGNTMAP_DEBUG
 else
 DEF_CFLAGS += -O3
 endif
diff -r 707569df20e1 -r 379dd201c36c tools/libxc/xc_minios.c
--- a/tools/libxc/xc_minios.c   Thu Jul 24 14:12:46 2008 +0100
+++ b/tools/libxc/xc_minios.c   Thu Jul 24 14:14:27 2008 +0100
@@ -15,6 +15,7 @@
 #include <os.h>
 #include <mm.h>
 #include <lib.h>
+#include <gntmap.h>
 #include <events.h>
 #include <wait.h>
 #include <sys/mman.h>
@@ -324,6 +325,76 @@ void discard_file_cache(int fd, int flus
     if (flush)
         fsync(fd);
 }
+
+int xc_gnttab_open(void)
+{
+    int xcg_handle;
+    xcg_handle = alloc_fd(FTYPE_GNTMAP);
+    gntmap_init(&files[xcg_handle].gntmap);
+    return xcg_handle;
+}
+
+int xc_gnttab_close(int xcg_handle)
+{
+    gntmap_fini(&files[xcg_handle].gntmap);
+    files[xcg_handle].type = FTYPE_NONE;
+    return 0;
+}
+
+void *xc_gnttab_map_grant_ref(int xcg_handle,
+                              uint32_t domid,
+                              uint32_t ref,
+                              int prot)
+{
+    return gntmap_map_grant_refs(&files[xcg_handle].gntmap,
+                                 1,
+                                 &domid, 0,
+                                 &ref,
+                                 prot & PROT_WRITE);
+}
+
+void *xc_gnttab_map_grant_refs(int xcg_handle,
+                               uint32_t count,
+                               uint32_t *domids,
+                               uint32_t *refs,
+                               int prot)
+{
+    return gntmap_map_grant_refs(&files[xcg_handle].gntmap,
+                                 count,
+                                 domids, 1,
+                                 refs,
+                                 prot & PROT_WRITE);
+}
+
+void *xc_gnttab_map_domain_grant_refs(int xcg_handle,
+                                      uint32_t count,
+                                      uint32_t domid,
+                                      uint32_t *refs,
+                                      int prot)
+{
+    return gntmap_map_grant_refs(&files[xcg_handle].gntmap,
+                                 count,
+                                 &domid, 0,
+                                 refs,
+                                 prot & PROT_WRITE);
+}
+
+int xc_gnttab_munmap(int xcg_handle,
+                     void *start_address,
+                     uint32_t count)
+{
+    return gntmap_munmap(&files[xcg_handle].gntmap,
+                         (unsigned long) start_address,
+                         count);
+}
+
+int xc_gnttab_set_max_grants(int xcg_handle,
+                             uint32_t count)
+{
+    return gntmap_set_max_grants(&files[xcg_handle].gntmap,
+                                 count);
+}
+
 /*
  * Local variables:
  * mode: C

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

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-changelog] [xen-unstable] minios: grant table map (gntdev) for minios, Xen patchbot-unstable <=