@@ -30,6 +30,11 @@
#include <sys/vfs.h>
#include <sys/stat.h>
#include <attr/xattr.h>
+#include <sys/ioctl.h>
+#include <linux/fs.h>
+#ifdef CONFIG_LINUX_MAGIC_H
+#include <linux/magic.h>
+#endif
#include "qemu-common.h"
#include "virtio-9p-marshal.h"
#include "hw/9pfs/virtio-9p-proxy.h"
@@ -38,6 +43,19 @@
#define PROGNAME "virtfs-proxy-helper"
+#ifndef XFS_SUPER_MAGIC
+#define XFS_SUPER_MAGIC 0x58465342
+#endif
+#ifndef EXT2_SUPER_MAGIC
+#define EXT2_SUPER_MAGIC 0xEF53
+#endif
+#ifndef REISERFS_SUPER_MAGIC
+#define REISERFS_SUPER_MAGIC 0x52654973
+#endif
+#ifndef BTRFS_SUPER_MAGIC
+#define BTRFS_SUPER_MAGIC 0x9123683E
+#endif
+
static struct option helper_opts[] = {
{"fd", required_argument, NULL, 'f'},
{"path", required_argument, NULL, 'p'},
@@ -45,6 +63,7 @@ static struct option helper_opts[] = {
};
int is_daemon;
+int get_version; /* IOC getversion IOCTL supported */
static void do_perror(const char *string)
{
@@ -284,6 +303,42 @@ static int send_response(int sock, struct iovec *iovec, int size)
return 0;
}
+/*
+ * gets generation number
+ * returns -errno on failure and sizeof(generation number) on success
+ */
+static int do_getversion(struct iovec *iovec, struct iovec *out_iovec)
+{
+ int fd, retval;
+ uint64_t version;
+ V9fsString path;
+
+ retval = sizeof(version);
+ /* no need to issue ioctl */
+ if (!get_version) {
+ version = 0;
+ proxy_marshal(out_iovec, 1, HDR_SZ, "q", version);
+ return retval;
+ }
+
+ proxy_unmarshal(iovec, 1, HDR_SZ, "s", &path);
+
+ fd = open(path.data, O_RDONLY);
+ if (fd < 0) {
+ retval = -errno;
+ goto done;
+ }
+ if (ioctl(fd, FS_IOC_GETVERSION, &version) < 0) {
+ retval = -errno;
+ } else {
+ proxy_marshal(out_iovec, 1, HDR_SZ, "q", version);
+ }
+ close(fd);
+done:
+ v9fs_string_free(&path);
+ return retval;
+}
+
static int do_getxattr(int type, struct iovec *iovec, struct iovec *out_iovec)
{
int size = 0, offset, retval;
@@ -667,6 +722,9 @@ static int process_requests(int sock)
v9fs_string_free(&path);
v9fs_string_free(&name);
break;
+ case T_GETVERSION:
+ size = do_getversion(&in_iovec, &out_iovec);
+ break;
default:
goto error;
break;
@@ -697,6 +755,7 @@ static int process_requests(int sock)
case T_READLINK:
case T_LGETXATTR:
case T_LLISTXATTR:
+ case T_GETVERSION:
if (send_response(sock, &out_iovec, size) < 0) {
goto error;
}
@@ -718,6 +777,8 @@ int main(int argc, char **argv)
char rpath[PATH_MAX];
struct stat stbuf;
int c, option_index;
+ int retval;
+ struct statfs st_fs;
is_daemon = 1;
rpath[0] = '\0';
@@ -775,6 +836,19 @@ int main(int argc, char **argv)
do_log(LOG_INFO, "Started");
+ /* check whether underlying FS support IOC_GETVERSION */
+ retval = statfs(rpath, &st_fs);
+ if (!retval) {
+ switch (st_fs.f_type) {
+ case EXT2_SUPER_MAGIC:
+ case BTRFS_SUPER_MAGIC:
+ case REISERFS_SUPER_MAGIC:
+ case XFS_SUPER_MAGIC:
+ get_version = 1;
+ break;
+ }
+ }
+
if (chroot(rpath) < 0) {
do_perror("chroot");
goto error;
@@ -209,6 +209,9 @@ static int v9fs_receive_response(V9fsProxy *proxy, int type,
}
break;
}
+ case T_GETVERSION:
+ proxy_unmarshal(reply, 1, HDR_SZ, "q", response);
+ break;
default:
*sock_error = 1;
return -1;
@@ -450,6 +453,13 @@ static int v9fs_request(V9fsProxy *proxy, int type,
proxy_marshal(iovec, 1, 0, "dd", header.type, header.size);
header.size += HDR_SZ;
break;
+ case T_GETVERSION:
+ path = va_arg(ap, V9fsString *);
+ header.size = proxy_marshal(iovec, 1, HDR_SZ, "s", path);
+ header.type = T_GETVERSION;
+ proxy_marshal(iovec, 1, 0, "dd", header.type, header.size);
+ header.size += HDR_SZ;
+ break;
default:
error_report("Invalid type %d\n", type);
va_end(ap);
@@ -497,6 +507,7 @@ static int v9fs_request(V9fsProxy *proxy, int type,
case T_STATFS:
case T_LGETXATTR:
case T_LLISTXATTR:
+ case T_GETVERSION:
retval = v9fs_receive_response(proxy, type, &sock_error, size,
response);
if (sock_error) {
@@ -978,6 +989,25 @@ static int proxy_unlinkat(FsContext *ctx, V9fsPath *dir,
return ret;
}
+static int proxy_ioc_getversion(FsContext *fs_ctx, V9fsPath *path,
+ mode_t st_mode, uint64_t *st_gen)
+{
+ int err;
+
+ /* Do not try to open special files like device nodes, fifos etc
+ * we can get fd for regular files and directories only
+ */
+ if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
+ return 0;
+ }
+ err = v9fs_request(fs_ctx->private, T_GETVERSION, st_gen, "s", path);
+ if (err < 0) {
+ errno = -err;
+ err = -1;
+ }
+ return err;
+}
+
static int proxy_parse_opts(QemuOpts *opts, struct FsDriverEntry *fs)
{
const char *sock_fd = qemu_opt_get(opts, "sock_fd");
@@ -1012,6 +1042,7 @@ static int proxy_init(FsContext *ctx)
qemu_mutex_init(&proxy->mutex);
ctx->export_flags |= V9FS_PATHNAME_FSCONTEXT;
+ ctx->exops.get_st_gen = proxy_ioc_getversion;
return 0;
}
@@ -43,6 +43,7 @@ enum {
T_LLISTXATTR,
T_LSETXATTR,
T_LREMOVEXATTR,
+ T_GETVERSION,
};
typedef struct {
Add proxy getversion to get generation number Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com> --- fsdev/virtfs-proxy-helper.c | 74 +++++++++++++++++++++++++++++++++++++++++++ hw/9pfs/virtio-9p-proxy.c | 31 ++++++++++++++++++ hw/9pfs/virtio-9p-proxy.h | 1 + 3 files changed, 106 insertions(+), 0 deletions(-)