new file mode 100644
@@ -0,0 +1,280 @@
+/*
+ * Minimal 9pfs PV frontend for Mini-OS.
+ * Copyright (c) 2023 Juergen Gross, SUSE Software Solution GmbH
+ */
+
+#include <mini-os/os.h>
+#include <mini-os/lib.h>
+#include <mini-os/events.h>
+#include <mini-os/gnttab.h>
+#include <mini-os/xenbus.h>
+#include <mini-os/xmalloc.h>
+#include <errno.h>
+#include <xen/io/9pfs.h>
+#include <mini-os/9pfront.h>
+
+#ifdef HAVE_LIBC
+struct dev_9pfs {
+ int id;
+ char nodename[20];
+ unsigned int dom;
+ char *backend;
+
+ char *tag;
+ const char *mnt;
+
+ struct xen_9pfs_data_intf *intf;
+ struct xen_9pfs_data data;
+ RING_IDX prod_pvt_out;
+ RING_IDX cons_pvt_in;
+
+ grant_ref_t ring_ref;
+ evtchn_port_t evtchn;
+ unsigned int ring_order;
+ xenbus_event_queue events;
+};
+
+#define DEFAULT_9PFS_RING_ORDER 4
+
+static unsigned int ftype_9pfs;
+
+static void intr_9pfs(evtchn_port_t port, struct pt_regs *regs, void *data)
+{
+}
+
+static int open_9pfs(struct mount_point *mnt, const char *pathname, int flags,
+ mode_t mode)
+{
+ errno = ENOSYS;
+
+ return -1;
+}
+
+static void free_9pfront(struct dev_9pfs *dev)
+{
+ unsigned int i;
+
+ if ( dev->data.in && dev->intf )
+ {
+ for ( i = 0; i < (1 << dev->ring_order); i++ )
+ gnttab_end_access(dev->intf->ref[i]);
+ free_pages(dev->data.in, dev->ring_order);
+ }
+ unbind_evtchn(dev->evtchn);
+ gnttab_end_access(dev->ring_ref);
+ free_page(dev->intf);
+ free(dev->backend);
+ free(dev->tag);
+ free(dev);
+}
+
+void *init_9pfront(unsigned int id, const char *mnt)
+{
+ struct dev_9pfs *dev;
+ char *msg;
+ char *reason = "";
+ xenbus_transaction_t xbt;
+ int retry = 1;
+ char bepath[64] = { 0 };
+ XenbusState state;
+ unsigned int i;
+ void *addr;
+ char *version;
+ char *v;
+
+ printk("9pfsfront add %u, for mount at %s\n", id, mnt);
+ dev = malloc(sizeof(*dev));
+ memset(dev, 0, sizeof(*dev));
+ snprintf(dev->nodename, sizeof(dev->nodename), "device/9pfs/%u", id);
+ dev->id = id;
+
+ msg = xenbus_read_unsigned(XBT_NIL, dev->nodename, "backend-id", &dev->dom);
+ if ( msg )
+ goto err;
+ msg = xenbus_read_string(XBT_NIL, dev->nodename, "backend", &dev->backend);
+ if ( msg )
+ goto err;
+ msg = xenbus_read_string(XBT_NIL, dev->nodename, "tag", &dev->tag);
+ if ( msg )
+ goto err;
+
+ snprintf(bepath, sizeof(bepath), "%s/state", dev->backend);
+ free(xenbus_watch_path_token(XBT_NIL, bepath, bepath, &dev->events));
+ state = xenbus_read_integer(bepath);
+ while ( msg == NULL && state < XenbusStateInitWait )
+ msg = xenbus_wait_for_state_change(bepath, &state, &dev->events);
+ if ( msg || state != XenbusStateInitWait )
+ {
+ reason = "illegal backend state";
+ goto err;
+ }
+
+ msg = xenbus_read_unsigned(XBT_NIL, dev->backend, "max-ring-page-order",
+ &dev->ring_order);
+ if ( msg )
+ goto err;
+ if ( dev->ring_order > DEFAULT_9PFS_RING_ORDER )
+ dev->ring_order = DEFAULT_9PFS_RING_ORDER;
+
+ msg = xenbus_read_string(XBT_NIL, dev->backend, "versions", &version);
+ if ( msg )
+ goto err;
+ for ( v = version; *v; v++ )
+ {
+ if ( strtoul(v, &v, 10) == 1 )
+ {
+ v = NULL;
+ break;
+ }
+ }
+ free(version);
+ if ( v )
+ {
+ reason = "version 1 not supported";
+ goto err;
+ }
+
+ dev->ring_ref = gnttab_alloc_and_grant((void **)&dev->intf);
+ memset(dev->intf, 0, PAGE_SIZE);
+ if ( evtchn_alloc_unbound(dev->dom, intr_9pfs, dev, &dev->evtchn) )
+ {
+ reason = "no event channel";
+ goto err;
+ }
+ dev->intf->ring_order = dev->ring_order;
+ dev->data.in = (void *)alloc_pages(dev->ring_order);
+ dev->data.out = dev->data.in + XEN_FLEX_RING_SIZE(dev->ring_order);
+ for ( i = 0; i < (1 << dev->ring_order); i++ )
+ {
+ addr = dev->data.in + i * PAGE_SIZE;
+ dev->intf->ref[i] = gnttab_grant_access(dev->dom, virt_to_mfn(addr), 0);
+ }
+
+ while ( retry )
+ {
+ msg = xenbus_transaction_start(&xbt);
+ if ( msg )
+ {
+ free(msg);
+ msg = NULL;
+ reason = "starting transaction";
+ goto err;
+ }
+
+ msg = xenbus_printf(xbt, dev->nodename, "version", "%u", 1);
+ if ( msg )
+ goto err_tr;
+ msg = xenbus_printf(xbt, dev->nodename, "num-rings", "%u", 1);
+ if ( msg )
+ goto err_tr;
+ msg = xenbus_printf(xbt, dev->nodename, "ring-ref0", "%u",
+ dev->ring_ref);
+ if ( msg )
+ goto err_tr;
+ msg = xenbus_printf(xbt, dev->nodename, "event-channel-0", "%u",
+ dev->evtchn);
+ if ( msg )
+ goto err_tr;
+ msg = xenbus_printf(xbt, dev->nodename, "state", "%u",
+ XenbusStateInitialised);
+ if ( msg )
+ goto err_tr;
+
+ free(xenbus_transaction_end(xbt, 0, &retry));
+ }
+
+ state = xenbus_read_integer(bepath);
+ while ( msg == NULL && state < XenbusStateConnected )
+ msg = xenbus_wait_for_state_change(bepath, &state, &dev->events);
+ if ( msg || state != XenbusStateConnected )
+ {
+ reason = "illegal backend state";
+ goto err;
+ }
+
+ msg = xenbus_printf(XBT_NIL, dev->nodename, "state", "%u",
+ XenbusStateConnected);
+ if ( msg )
+ goto err;
+
+ unmask_evtchn(dev->evtchn);
+
+ dev->mnt = mnt;
+ if ( mount(dev->mnt, dev, open_9pfs) )
+ {
+ reason = "mount failed";
+ goto err;
+ }
+
+ return dev;
+
+ err_tr:
+ free(xenbus_transaction_end(xbt, 1, &retry));
+
+ err:
+ if ( bepath[0] )
+ free(xenbus_unwatch_path_token(XBT_NIL, bepath, bepath));
+ if ( msg )
+ printk("9pfsfront add %u failed, error %s accessing Xenstore\n",
+ id, msg);
+ else
+ printk("9pfsfront add %u failed, %s\n", id, reason);
+ free_9pfront(dev);
+ free(msg);
+ return NULL;
+}
+
+void shutdown_9pfront(void *dev)
+{
+ struct dev_9pfs *dev9p = dev;
+ char bepath[64];
+ XenbusState state;
+ char *msg;
+ char *reason = "";
+
+ umount(dev9p->mnt);
+ snprintf(bepath, sizeof(bepath), "%s/state", dev9p->backend);
+
+ msg = xenbus_printf(XBT_NIL, dev9p->nodename, "state", "%u",
+ XenbusStateClosing);
+ if ( msg )
+ goto err;
+
+ state = xenbus_read_integer(bepath);
+ while ( msg == NULL && state < XenbusStateClosing)
+ msg = xenbus_wait_for_state_change(bepath, &state, &dev9p->events);
+ if ( msg || state != XenbusStateClosing )
+ {
+ reason = "illegal backend state";
+ goto err;
+ }
+
+ msg = xenbus_printf(XBT_NIL, dev9p->nodename, "state", "%u",
+ XenbusStateClosed);
+ if ( msg )
+ goto err;
+
+ free_9pfront(dev9p);
+
+ return;
+
+ err:
+ if ( msg )
+ printk("9pfsfront shutdown %u failed, error %s accessing Xenstore\n",
+ dev9p->id, msg);
+ else
+ printk("9pfsfront shutdown %u failed, %s\n", dev9p->id, reason);
+ free(msg);
+}
+
+static const struct file_ops ops_9pfs = {
+ .name = "9pfs",
+};
+
+__attribute__((constructor))
+static void initialize_9pfs(void)
+{
+ ftype_9pfs = alloc_file_type(&ops_9pfs);
+}
+
+#endif /* HAVE_LIBC */
@@ -187,6 +187,7 @@ CONFIG-n += CONFIG_QEMU_XS_ARGS
CONFIG-n += CONFIG_TEST
CONFIG-n += CONFIG_PCIFRONT
CONFIG-n += CONFIG_TPMFRONT
+CONFIG-n += CONFIG_9PFRONT
CONFIG-n += CONFIG_TPM_TIS
CONFIG-n += CONFIG_TPMBACK
CONFIG-n += CONFIG_BALLOON
@@ -39,6 +39,7 @@ SUBDIRS := lib
src-$(CONFIG_BLKFRONT) += blkfront.c
src-$(CONFIG_CONSFRONT) += consfront.c
src-$(CONFIG_TPMFRONT) += tpmfront.c
+src-$(CONFIG_9PFRONT) += 9pfront.c
src-$(CONFIG_TPM_TIS) += tpm_tis.c
src-$(CONFIG_TPMBACK) += tpmback.c
src-y += console.c
@@ -12,6 +12,7 @@ CONFIG_NETFRONT = n
CONFIG_FBFRONT = n
CONFIG_KBDFRONT = n
CONFIG_CONSFRONT = n
+CONFIG_9PFRONT = n
CONFIG_XENBUS = n
CONFIG_LIBXS = n
CONFIG_LWIP = n
@@ -12,6 +12,7 @@ CONFIG_NETFRONT = y
CONFIG_FBFRONT = y
CONFIG_KBDFRONT = y
CONFIG_CONSFRONT = y
+CONFIG_9PFRONT = y
CONFIG_XENBUS = y
CONFIG_LIBXS = y
CONFIG_BALLOON = y
@@ -12,6 +12,7 @@ CONFIG_NETFRONT = y
CONFIG_FBFRONT = y
CONFIG_KBDFRONT = y
CONFIG_CONSFRONT = y
+CONFIG_9PFRONT = y
CONFIG_XENBUS = y
CONFIG_LIBXS = y
CONFIG_BALLOON = y
new file mode 100644
@@ -0,0 +1,7 @@
+#ifndef __9PFRONT_H__
+#define __9PFRONT_H__
+
+void *init_9pfront(unsigned int id, const char *mnt);
+void shutdown_9pfront(void *dev);
+
+#endif /* __9PFRONT_H__ */
Add a frontend for the 9pfs PV device. For now add only the code needed to connect to the backend and the related disconnect functionality. The 9pfs protocol support will be added later. Due to its nature (ability to access files) the whole code is guarded by "#ifdef HAVE_LIBC". Signed-off-by: Juergen Gross <jgross@suse.com> --- 9pfront.c | 280 ++++++++++++++++++++++++++++++++++ Config.mk | 1 + Makefile | 1 + arch/x86/testbuild/all-no | 1 + arch/x86/testbuild/all-yes | 1 + arch/x86/testbuild/newxen-yes | 1 + include/9pfront.h | 7 + 7 files changed, 292 insertions(+) create mode 100644 9pfront.c create mode 100644 include/9pfront.h