Use /dev/kmem to map dom0 xenstore page instead of abusing the foreign mapping interface.

Change /proc/xen/xsd_mfn to /proc/xen/xsd_kva containing the kernel
virtual address of the dom0 xenstore page.  Update xenstored to use
/proc/xen/xsd_kva.

Signed-off-by: Keir Fraser <keir@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>

diff --git a/linux-2.6-xen-sparse/arch/i386/mm/ioremap-xen.c b/linux-2.6-xen-sparse/arch/i386/mm/ioremap-xen.c
index f0a908a17f986e7201e829a0488cf51b9a760135..a9a32ba8fb6e1191b14b2324e70e5d0dc2d6d687 100644 (file)
--- a/linux-2.6-xen-sparse/arch/i386/mm/ioremap-xen.c
+++ b/linux-2.6-xen-sparse/arch/i386/mm/ioremap-xen.c
@@ -122,6 +122,9 @@ int direct_remap_pfn_range(struct vm_area_struct *vma,
        /* Same as remap_pfn_range(). */
        vma->vm_flags |= VM_IO | VM_RESERVED;
 
+       if (domid == DOMID_SELF)
+               return -EINVAL;
+
        return __direct_remap_pfn_range(
                vma->vm_mm, address, mfn, size, prot, domid);
 }

diff --git a/linux-2.6-xen-sparse/drivers/xen/privcmd/privcmd.c b/linux-2.6-xen-sparse/drivers/xen/privcmd/privcmd.c
index 75ef91dedf1bd3d1f1f21744aeeca0a46282e591..7758ca5cd936db44f6d975a3db3ac6a96b595c16 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/privcmd/privcmd.c
+++ b/linux-2.6-xen-sparse/drivers/xen/privcmd/privcmd.c
@@ -163,7 +163,12 @@ static int privcmd_ioctl(struct inode *inode, struct file *file,
                        goto batch_err;
                }
 
-               vma = find_vma( current->mm, m.addr );
+               if (m.dom == DOMID_SELF) {
+                       ret = -EINVAL;
+                       goto batch_err;
+               }
+
+               vma = find_vma(current->mm, m.addr);
                if (!vma) {
                        ret = -EINVAL;
                        goto batch_err;

diff --git a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c
index 14af1a512f0f52210a0bf3395ef048c2fd7494e0..cd4732c8fd2f12f09d45b862bee3c3795adadc63 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c
+++ b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c
@@ -863,16 +863,16 @@ EXPORT_SYMBOL(xenbus_resume);
 
 
 /* A flag to determine if xenstored is 'ready' (i.e. has started) */
-int xenstored_ready = 0; 
+int xenstored_ready = 0;
 
 
 int register_xenstore_notifier(struct notifier_block *nb)
 {
        int ret = 0;
 
-       if (xenstored_ready > 0) 
+       if (xenstored_ready > 0)
                ret = nb->notifier_call(nb, 0, NULL);
-       else 
+       else
                notifier_chain_register(&xenstore_chain, nb);
 
        return ret;
@@ -889,7 +889,7 @@ EXPORT_SYMBOL(unregister_xenstore_notifier);
 
 void xenbus_probe(void *unused)
 {
-       BUG_ON((xenstored_ready <= 0)); 
+       BUG_ON((xenstored_ready <= 0));
 
        /* Enumerate devices in xenstore. */
        xenbus_probe_devices(&xenbus_frontend);
@@ -904,27 +904,27 @@ void xenbus_probe(void *unused)
 }
 
 
-static struct proc_dir_entry *xsd_mfn_intf;
+static struct proc_dir_entry *xsd_kva_intf;
 static struct proc_dir_entry *xsd_port_intf;
 
 
-static int xsd_mfn_read(char *page, char **start, off_t off,
+static int xsd_kva_read(char *page, char **start, off_t off,
                         int count, int *eof, void *data)
 {
-       int len; 
-       len  = sprintf(page, "%ld", xen_start_info->store_mfn); 
-       *eof = 1; 
-       return len; 
+       int len;
+       len  = sprintf(page, "0x%p", mfn_to_virt(xen_start_info->store_mfn));
+       *eof = 1;
+       return len;
 }
 
 static int xsd_port_read(char *page, char **start, off_t off,
                         int count, int *eof, void *data)
 {
-       int len; 
+       int len;
 
-       len  = sprintf(page, "%d", xen_start_info->store_evtchn); 
-       *eof = 1; 
-       return len; 
+       len  = sprintf(page, "%d", xen_start_info->store_evtchn);
+       *eof = 1;
+       return len;
 }
 
 
@@ -959,8 +959,8 @@ static int __init xenbus_probe_init(void)
 
                /* Allocate page. */
                page = get_zeroed_page(GFP_KERNEL);
-               if (!page) 
-                       return -ENOMEM; 
+               if (!page)
+                       return -ENOMEM;
 
                /* We don't refcnt properly, so set reserved on page.
                 * (this allocation is permanent) */
@@ -973,25 +973,25 @@ static int __init xenbus_probe_init(void)
                /* Next allocate a local port which xenstored can bind to */
                op.cmd = EVTCHNOP_alloc_unbound;
                op.u.alloc_unbound.dom        = DOMID_SELF;
-               op.u.alloc_unbound.remote_dom = 0; 
+               op.u.alloc_unbound.remote_dom = 0;
 
                ret = HYPERVISOR_event_channel_op(&op);
-               BUG_ON(ret); 
+               BUG_ON(ret);
                xen_start_info->store_evtchn = op.u.alloc_unbound.port;
 
                /* And finally publish the above info in /proc/xen */
-               if((xsd_mfn_intf = create_xen_proc_entry("xsd_mfn", 0400)))
-                       xsd_mfn_intf->read_proc = xsd_mfn_read; 
+               if((xsd_kva_intf = create_xen_proc_entry("xsd_kva", 0400)))
+                       xsd_kva_intf->read_proc = xsd_kva_read;
                if((xsd_port_intf = create_xen_proc_entry("xsd_port", 0400)))
                        xsd_port_intf->read_proc = xsd_port_read;
        }
 
        /* Initialize the interface to xenstore. */
-       err = xs_init(); 
+       err = xs_init();
        if (err) {
                printk(KERN_WARNING
                       "XENBUS: Error initializing xenstore comms: %i\n", err);
-               return err; 
+               return err;
        }
 
        if (!dom0) {

diff --git a/tools/xenstore/xenstored_domain.c b/tools/xenstore/xenstored_domain.c
index fb7377178744a9359b403337fc8df0599ba9c773..563f07e596f177e650012545fcb983470a2ff4fd 100644 (file)
--- a/tools/xenstore/xenstored_domain.c
+++ b/tools/xenstore/xenstored_domain.c
@@ -27,6 +27,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
+#include <paths.h>
 
 //#define DEBUG
 #include "utils.h"
@@ -256,7 +257,7 @@ static char *talloc_domain_path(void *context, unsigned int domid)
 }
 
 static struct domain *new_domain(void *context, unsigned int domid,
-                                unsigned long mfn, int port)
+                                int port)
 {
        struct domain *domain;
        struct ioctl_evtchn_bind_interdomain bind;
@@ -268,11 +269,6 @@ static struct domain *new_domain(void *context, unsigned int domid,
        domain->shutdown = 0;
        domain->domid = domid;
        domain->path = talloc_domain_path(domain, domid);
-       domain->interface = xc_map_foreign_range(
-               *xc_handle, domain->domid,
-               getpagesize(), PROT_READ|PROT_WRITE, mfn);
-       if (!domain->interface)
-               return NULL;
 
        list_add(&domain->list, &domains);
        talloc_set_destructor(domain, destroy_domain);
@@ -290,7 +286,6 @@ static struct domain *new_domain(void *context, unsigned int domid,
        domain->conn->id = domid;
 
        domain->remote_port = port;
-       domain->mfn = mfn;
 
        return domain;
 }
@@ -341,11 +336,19 @@ void do_introduce(struct connection *conn, struct buffered_data *in)
 
        if (domain == NULL) {
                /* Hang domain off "in" until we're finished. */
-               domain = new_domain(in, domid, mfn, port);
+               domain = new_domain(in, domid, port);
                if (!domain) {
                        send_error(conn, errno);
                        return;
                }
+               domain->interface = xc_map_foreign_range(
+                       *xc_handle, domid,
+                       getpagesize(), PROT_READ|PROT_WRITE, mfn);
+               if (!domain->interface) {
+                       send_error(conn, errno);
+                       return;
+               }
+               domain->mfn = mfn;
 
                /* Now domain belongs to its connection. */
                talloc_steal(domain->conn, domain);
@@ -463,11 +466,11 @@ static int dom0_init(void)
 { 
        int rc, fd;
        evtchn_port_t port; 
-       unsigned long mfn; 
+       unsigned long kva; 
        char str[20]; 
        struct domain *dom0; 
 
-       fd = open(XENSTORED_PROC_MFN, O_RDONLY); 
+       fd = open(XENSTORED_PROC_KVA, O_RDONLY); 
        if (fd == -1)
                return -1;
 
@@ -475,7 +478,7 @@ static int dom0_init(void)
        if (rc == -1)
                goto outfd;
        str[rc] = '\0'; 
-       mfn = strtoul(str, NULL, 0); 
+       kva = strtoul(str, NULL, 0); 
 
        close(fd); 
 
@@ -491,7 +494,19 @@ static int dom0_init(void)
 
        close(fd); 
 
-       dom0 = new_domain(NULL, 0, mfn, port); 
+       dom0 = new_domain(NULL, 0, port); 
+
+       fd = open(_PATH_KMEM, O_RDWR);
+       if (fd == -1)
+               return -1;
+
+       dom0->interface = mmap(NULL, getpagesize(), PROT_READ|PROT_WRITE,
+                              MAP_SHARED, fd, kva);
+       if (dom0->interface == MAP_FAILED)
+               goto outfd;
+
+       close(fd);
+
        talloc_steal(dom0->conn, dom0); 
 
        evtchn_notify(dom0->port); 

diff --git a/tools/xenstore/xenstored_proc.h b/tools/xenstore/xenstored_proc.h
index d065b05894a0e4f6d8dcb9a2f674ba80ba0b7dce..509ab658fd79e7f10047243cf55441f3b77f3514 100644 (file)
--- a/tools/xenstore/xenstored_proc.h
+++ b/tools/xenstore/xenstored_proc.h
@@ -20,7 +20,7 @@
 #ifndef _XENSTORED_PROC_H
 #define _XENSTORED_PROC_H
 
-#define XENSTORED_PROC_MFN  "/proc/xen/xsd_mfn"
+#define XENSTORED_PROC_KVA  "/proc/xen/xsd_kva"
 #define XENSTORED_PROC_PORT "/proc/xen/xsd_port"