[V2,08/12] hw/9pfs: xattr interfaces in proxy filesystem driver

diff --git a/fsdev/virtfs-proxy-helper.c b/fsdev/virtfs-proxy-helper.c
index ded0ead..ccd7ed8 100644
--- a/fsdev/virtfs-proxy-helper.c
+++ b/fsdev/virtfs-proxy-helper.c
@@ -29,6 +29,7 @@ 
 #include <sys/socket.h>
 #include <sys/vfs.h>
 #include <sys/stat.h>
+#include <attr/xattr.h>
 #include "qemu-common.h"
 #include "virtio-9p-marshal.h"
 #include "hw/9pfs/virtio-9p-proxy.h"
@@ -283,6 +284,50 @@  static int send_response(int sock, struct iovec *iovec, int size)
     return 0;
 }
 
+static int do_getxattr(int type, struct iovec *iovec, struct iovec *out_iovec)
+{
+    int size = 0, offset, retval;
+    V9fsString path, name, xattr;
+
+    v9fs_string_init(&xattr);
+
+    offset = HDR_SZ;
+    offset += proxy_unmarshal(iovec, 1, HDR_SZ, "ds", &size, &path);
+    if (size) {
+        xattr.data = g_malloc(size);
+        xattr.size = size;
+    }
+    switch (type) {
+    case T_LGETXATTR:
+        proxy_unmarshal(iovec, 1, offset, "s", &name);
+        retval = lgetxattr(path.data, name.data, xattr.data, size);
+        if (retval < 0) {
+            retval = -errno;
+            v9fs_string_free(&name);
+            goto error;
+        }
+    	v9fs_string_free(&name);
+        break;
+    case T_LLISTXATTR:
+        retval = llistxattr(path.data, xattr.data, size);
+        if (retval < 0) {
+            retval = -errno;
+            goto error;
+        }
+        break;
+    }
+
+    if (!size) {
+        proxy_marshal(out_iovec, 1, HDR_SZ, "d", retval);
+        retval = sizeof(retval);
+    } else {
+        retval = proxy_marshal(out_iovec, 1, HDR_SZ, "s", &xattr);
+    }
+error:
+    v9fs_string_free(&path);
+    return retval;
+}
+
 static void stat_to_prstat(ProxyStat *pr_stat, struct stat *stat)
 {
     memset(pr_stat, 0, sizeof(*pr_stat));
@@ -499,9 +544,10 @@  static int process_requests(int sock)
     int mode, uid, gid;
     struct timespec spec[2];
     int type, retval = 0;
+    V9fsString name, value;
     V9fsString oldpath, path;
     struct iovec in_iovec, out_iovec;
-    int size = 0;
+    int size = 0, flags;
 
     in_iovec.iov_base = g_malloc(BUFF_SZ);
     in_iovec.iov_len = BUFF_SZ;
@@ -595,6 +641,32 @@  static int process_requests(int sock)
             }
             v9fs_string_free(&path);
             break;
+        case T_LGETXATTR:
+        case T_LLISTXATTR:
+            size = do_getxattr(type, &in_iovec, &out_iovec);
+            break;
+        case T_LSETXATTR:
+            proxy_unmarshal(&in_iovec, 1, HDR_SZ,
+                           "sssdd", &path, &name, &value, &size,
+                           &flags);
+            retval = lsetxattr(path.data, name.data, value.data, size, flags);
+            if (retval < 0) {
+                retval = -errno;
+            }
+            v9fs_string_free(&path);
+            v9fs_string_free(&name);
+            v9fs_string_free(&value);
+            break;
+        case T_LREMOVEXATTR:
+            proxy_unmarshal(&in_iovec, 1,
+                           HDR_SZ, "ss", &path, &name);
+            retval = lremovexattr(path.data, name.data);
+            if (retval < 0) {
+                retval = -errno;
+            }
+            v9fs_string_free(&path);
+            v9fs_string_free(&name);
+            break;
         default:
             goto error;
             break;
@@ -616,11 +688,15 @@  static int process_requests(int sock)
         case T_UTIME:
         case T_RENAME:
         case T_REMOVE:
+        case T_LSETXATTR:
+        case T_LREMOVEXATTR:
             send_status(sock, &out_iovec, retval);
             break;
         case T_LSTAT:
         case T_STATFS:
         case T_READLINK:
+        case T_LGETXATTR:
+        case T_LLISTXATTR:
             if (send_response(sock, &out_iovec, size) < 0) {
                 goto error;
             }
diff --git a/hw/9pfs/virtio-9p-proxy.c b/hw/9pfs/virtio-9p-proxy.c
index aefdc61..f672ac3 100644
--- a/hw/9pfs/virtio-9p-proxy.c
+++ b/hw/9pfs/virtio-9p-proxy.c
@@ -136,7 +136,7 @@  static void prstat_to_stat(struct stat *stbuf, ProxyStat *prstat)
  * size of errno/response is given by header.size
  */
 static int v9fs_receive_response(V9fsProxy *proxy, int type,
-                int *sock_error, void *response)
+                int *sock_error, int size, void *response)
 {
     int retval, error;
     ProxyHeader header;
@@ -196,6 +196,19 @@  static int v9fs_receive_response(V9fsProxy *proxy, int type,
         v9fs_string_free(&target);
         break;
     }
+    case T_LGETXATTR:
+    case T_LLISTXATTR: {
+        V9fsString xattr;
+        if (!size) {
+            proxy_unmarshal(reply, 1, HDR_SZ, "d", &size);
+            return size;
+        } else {
+            proxy_unmarshal(reply, 1, HDR_SZ, "s", &xattr);
+            memcpy(response, xattr.data, xattr.size);
+            v9fs_string_free(&xattr);
+        }
+        break;
+    }
     default:
         *sock_error = 1;
         return -1;
@@ -244,6 +257,7 @@  static int v9fs_request(V9fsProxy *proxy, int type,
     int size = 0;
     struct timespec spec[2];
     uint64_t offset;
+    V9fsString *name, *value;
 
     qemu_mutex_lock(&proxy->mutex);
 
@@ -398,6 +412,44 @@  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_LGETXATTR:
+        size = va_arg(ap, int);
+        path = va_arg(ap, V9fsString *);
+        name = va_arg(ap, V9fsString *);
+        header.size = proxy_marshal(iovec, 1, HDR_SZ, "dss", size,
+			path, name);
+        header.type = T_LGETXATTR;
+        proxy_marshal(iovec, 1, 0, "dd", header.type, header.size);
+        header.size += HDR_SZ;
+        break;
+    case T_LLISTXATTR:
+        size = va_arg(ap, int);
+        path = va_arg(ap, V9fsString *);
+        header.size = proxy_marshal(iovec, 1, HDR_SZ, "ds", size, path);
+        header.type = T_LLISTXATTR;
+        proxy_marshal(iovec, 1, 0, "dd", header.type, header.size);
+        header.size += HDR_SZ;
+        break;
+    case T_LSETXATTR:
+        path = va_arg(ap, V9fsString *);
+        name = va_arg(ap, V9fsString *);
+        value = va_arg(ap, V9fsString *);
+        size = va_arg(ap, int);
+        flags = va_arg(ap, int);
+        header.size = proxy_marshal(iovec, 1, HDR_SZ, "sssdd",
+                                   path, name, value, size, flags);
+        header.type = T_LSETXATTR;
+        proxy_marshal(iovec, 1, 0, "dd", header.type, header.size);
+        header.size += HDR_SZ;
+        break;
+    case T_LREMOVEXATTR:
+        path = va_arg(ap, V9fsString *);
+        name = va_arg(ap, V9fsString *);
+        header.size = proxy_marshal(iovec, 1, HDR_SZ, "ss", path, name);
+        header.type = T_LREMOVEXATTR;
+        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);
@@ -433,6 +485,8 @@  static int v9fs_request(V9fsProxy *proxy, int type,
     case T_TRUNCATE:
     case T_UTIME:
     case T_REMOVE:
+    case T_LSETXATTR:
+    case T_LREMOVEXATTR:
         retval = v9fs_receive_status(proxy, &sock_error, reply);
         if (sock_error) {
             goto close_error;
@@ -441,7 +495,10 @@  static int v9fs_request(V9fsProxy *proxy, int type,
     case T_LSTAT:
     case T_READLINK:
     case T_STATFS:
-        retval = v9fs_receive_response(proxy, type, &sock_error, response);
+    case T_LGETXATTR:
+    case T_LLISTXATTR:
+        retval = v9fs_receive_response(proxy, type, &sock_error, size,
+                        response);
         if (sock_error) {
             goto close_error;
         }
@@ -807,29 +864,71 @@  static int proxy_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *stbuf)
 static ssize_t proxy_lgetxattr(FsContext *ctx, V9fsPath *fs_path,
                                const char *name, void *value, size_t size)
 {
-    errno = EOPNOTSUPP;
-    return -1;
+    int retval;
+    V9fsString xname;
+
+    v9fs_string_init(&xname);
+    v9fs_string_sprintf(&xname, "%s", name);
+    retval = v9fs_request(ctx->private, T_LGETXATTR, value, "dss", size,
+                          fs_path, &xname);
+    v9fs_string_free(&xname);
+    if (retval < 0) {
+        errno = -retval;
+    }
+    return retval;
 }
 
 static ssize_t proxy_llistxattr(FsContext *ctx, V9fsPath *fs_path,
                                 void *value, size_t size)
 {
-    errno = EOPNOTSUPP;
-    return -1;
+    int retval;
+    retval = v9fs_request(ctx->private, T_LLISTXATTR, value, "ds", size,
+                        fs_path);
+    if (retval < 0) {
+        errno = -retval;
+    }
+    return retval;
 }
 
 static int proxy_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name,
                            void *value, size_t size, int flags)
 {
-    errno = EOPNOTSUPP;
-    return -1;
+    int retval;
+    V9fsString xname, xvalue;
+
+    v9fs_string_init(&xname);
+    v9fs_string_sprintf(&xname, "%s", name);
+
+    v9fs_string_init(&xvalue);
+    xvalue.size = size;
+    xvalue.data = g_malloc(size);
+    memcpy(xvalue.data, value, size);
+
+    retval = v9fs_request(ctx->private, T_LSETXATTR, value, "sssdd",
+                          fs_path, &xname, &xvalue, size, flags);
+    v9fs_string_free(&xname);
+    v9fs_string_free(&xvalue);
+    if (retval < 0) {
+        errno = -retval;
+    }
+    return retval;
 }
 
 static int proxy_lremovexattr(FsContext *ctx, V9fsPath *fs_path,
                               const char *name)
 {
-    errno = EOPNOTSUPP;
-    return -1;
+    int retval;
+    V9fsString xname;
+
+    v9fs_string_init(&xname);
+    v9fs_string_sprintf(&xname, "%s", name);
+    retval = v9fs_request(ctx->private, T_LREMOVEXATTR, NULL, "ss",
+                          fs_path, &xname);
+    v9fs_string_free(&xname);
+    if (retval < 0) {
+        errno = -retval;
+    }
+    return retval;
 }
 
 static int proxy_name_to_path(FsContext *ctx, V9fsPath *dir_path,
diff --git a/hw/9pfs/virtio-9p-proxy.h b/hw/9pfs/virtio-9p-proxy.h
index ef8a0f3..4c691a8 100644
--- a/hw/9pfs/virtio-9p-proxy.h
+++ b/hw/9pfs/virtio-9p-proxy.h
@@ -39,6 +39,10 @@  enum {
     T_UTIME,
     T_RENAME,
     T_REMOVE,
+    T_LGETXATTR,
+    T_LLISTXATTR,
+    T_LSETXATTR,
+    T_LREMOVEXATTR,
 };
 
 typedef struct {