hw/9pfs: Use export flag for indicating security model

This helps to remove some of the structure members

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

fsdev/file-op-9p.h

@@ -23,23 +23,6 @@
 #define SM_LOCAL_MODE_BITS    0600
 #define SM_LOCAL_DIR_MODE_BITS    0700
 
-typedef enum
-{
-    /*
-     * Server will try to set uid/gid.
-     * On failure ignore the error.
-     */
-    SM_NONE = 0,
-    /*
-     * uid/gid set on fileserver files
-     */
-    SM_PASSTHROUGH = 1,
-    /*
-     * uid/gid part of xattr
-     */
-    SM_MAPPED,
-} SecModel;
-
 typedef struct FsCred
 {
     uid_t   fc_uid;
@@ -60,12 +43,27 @@ typedef struct extended_ops {
 /* export flags */
 #define V9FS_IMMEDIATE_WRITEOUT     0x00000001
 #define V9FS_PATHNAME_FSCONTEXT     0x00000002
+/*
+ * uid/gid set on fileserver files
+ */
+#define V9FS_SM_PASSTHROUGH         0x00000004
+/*
+ * uid/gid part of xattr
+ */
+#define V9FS_SM_MAPPED              0x00000008
+/*
+ * Server will try to set uid/gid.
+ * On failure ignore the error.
+ */
+#define V9FS_SM_NONE                0x00000010
+
+
+#define V9FS_SEC_MASK               0x0000001C
 
 typedef struct FsContext
 {
-    char *fs_root;
-    SecModel fs_sm;
     uid_t uid;
+    char *fs_root;
     int export_flags;
     struct xattr_operations **xops;
     struct extended_ops exops;

fsdev/qemu-fsdev.c

@@ -72,14 +72,29 @@ int qemu_fsdev_add(QemuOpts *opts)
 
     fsle->fse.fsdev_id = g_strdup(fsdev_id);
     fsle->fse.path = g_strdup(path);
-    fsle->fse.security_model = g_strdup(sec_model);
     fsle->fse.ops = FsDrivers[i].ops;
     fsle->fse.export_flags = 0;
     if (writeout) {
         if (!strcmp(writeout, "immediate")) {
-            fsle->fse.export_flags = V9FS_IMMEDIATE_WRITEOUT;
+            fsle->fse.export_flags |= V9FS_IMMEDIATE_WRITEOUT;
         }
     }
+
+    if (!strcmp(sec_model, "passthrough")) {
+        fsle->fse.export_flags |= V9FS_SM_PASSTHROUGH;
+    } else if (!strcmp(sec_model, "mapped")) {
+        fsle->fse.export_flags |= V9FS_SM_MAPPED;
+    } else if (!strcmp(sec_model, "none")) {
+        fsle->fse.export_flags |= V9FS_SM_NONE;
+    } else {
+        fprintf(stderr, "Default to security_model=none. You may want"
+                " enable advanced security model using "
+                "security option:\n\t security_model=passthrough\n\t "
+                "security_model=mapped\n");
+
+        fsle->fse.export_flags |= V9FS_SM_NONE;
+    }
+
     QTAILQ_INSERT_TAIL(&fsdriver_entries, fsle, next);
     return 0;
 }

fsdev/qemu-fsdev.h

@@ -40,7 +40,6 @@ typedef struct FsDriverTable {
 typedef struct FsDriverEntry {
     char *fsdev_id;
     char *path;
-    char *security_model;
     int export_flags;
     FileOperations *ops;
 } FsDriverEntry;

hw/9pfs/virtio-9p-device.c

@@ -83,35 +83,18 @@ VirtIODevice *virtio_9p_init(DeviceState *dev, V9fsConf *conf)
         exit(1);
     }
 
-    if (!strcmp(fse->security_model, "passthrough")) {
-        /* Files on the Fileserver set to client user credentials */
-        s->ctx.fs_sm = SM_PASSTHROUGH;
+    s->ctx.export_flags = fse->export_flags;
+    s->ctx.fs_root = g_strdup(fse->path);
+    s->ctx.exops.get_st_gen = NULL;
+
+    if (fse->export_flags & V9FS_SM_PASSTHROUGH) {
         s->ctx.xops = passthrough_xattr_ops;
-    } else if (!strcmp(fse->security_model, "mapped")) {
-        /* Files on the fileserver are set to QEMU credentials.
-         * Client user credentials are saved in extended attributes.
-         */
-        s->ctx.fs_sm = SM_MAPPED;
+    } else if (fse->export_flags & V9FS_SM_MAPPED) {
         s->ctx.xops = mapped_xattr_ops;
-    } else if (!strcmp(fse->security_model, "none")) {
-        /*
-         * Files on the fileserver are set to QEMU credentials.
-         */
-        s->ctx.fs_sm = SM_NONE;
-        s->ctx.xops = none_xattr_ops;
-    } else {
-        fprintf(stderr, "Default to security_model=none. You may want"
-                " enable advanced security model using "
-                "security option:\n\t security_model=passthrough\n\t "
-                "security_model=mapped\n");
-        s->ctx.fs_sm = SM_NONE;
+    } else if (fse->export_flags & V9FS_SM_NONE) {
         s->ctx.xops = none_xattr_ops;
     }
 
-    s->ctx.export_flags = fse->export_flags;
-    s->ctx.fs_root = g_strdup(fse->path);
-    s->ctx.exops.get_st_gen = NULL;
-
     len = strlen(conf->tag);
     if (len > MAX_TAG_LEN) {
         fprintf(stderr, "mount tag '%s' (%d bytes) is longer than "

hw/9pfs/virtio-9p-local.c

@@ -49,7 +49,7 @@ static int local_lstat(FsContext *fs_ctx, V9fsPath *fs_path, struct stat *stbuf)
     if (err) {
         return err;
     }
-    if (fs_ctx->fs_sm == SM_MAPPED) {
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         /* Actual credentials are part of extended attrs */
         uid_t tmp_uid;
         gid_t tmp_gid;
@@ -124,7 +124,7 @@ static int local_post_create_passthrough(FsContext *fs_ctx, const char *path,
          * If we fail to change ownership and if we are
          * using security model none. Ignore the error
          */
-        if (fs_ctx->fs_sm != SM_NONE) {
+        if ((fs_ctx->export_flags & V9FS_SEC_MASK) != V9FS_SM_NONE) {
             return -1;
         }
     }
@@ -138,7 +138,7 @@ static ssize_t local_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
     char buffer[PATH_MAX];
     char *path = fs_path->data;
 
-    if (fs_ctx->fs_sm == SM_MAPPED) {
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         int fd;
         fd = open(rpath(fs_ctx, path, buffer), O_RDONLY);
         if (fd == -1) {
@@ -149,8 +149,8 @@ static ssize_t local_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
         } while (tsize == -1 && errno == EINTR);
         close(fd);
         return tsize;
-    } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
-               (fs_ctx->fs_sm == SM_NONE)) {
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
         tsize = readlink(rpath(fs_ctx, path, buffer), buf, bufsz);
     }
     return tsize;
@@ -252,10 +252,10 @@ static int local_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
     char buffer[PATH_MAX];
     char *path = fs_path->data;
 
-    if (fs_ctx->fs_sm == SM_MAPPED) {
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         return local_set_xattr(rpath(fs_ctx, path, buffer), credp);
-    } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
-               (fs_ctx->fs_sm == SM_NONE)) {
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
         return chmod(rpath(fs_ctx, path, buffer), credp->fc_mode);
     }
     return -1;
@@ -275,7 +275,7 @@ static int local_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
     path = fullname.data;
 
     /* Determine the security model */
-    if (fs_ctx->fs_sm == SM_MAPPED) {
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         err = mknod(rpath(fs_ctx, path, buffer),
                 SM_LOCAL_MODE_BITS|S_IFREG, 0);
         if (err == -1) {
@@ -286,8 +286,8 @@ static int local_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
             serrno = errno;
             goto err_end;
         }
-    } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
-               (fs_ctx->fs_sm == SM_NONE)) {
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
         err = mknod(rpath(fs_ctx, path, buffer), credp->fc_mode,
                 credp->fc_rdev);
         if (err == -1) {
@@ -323,7 +323,7 @@ static int local_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
     path = fullname.data;
 
     /* Determine the security model */
-    if (fs_ctx->fs_sm == SM_MAPPED) {
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         err = mkdir(rpath(fs_ctx, path, buffer), SM_LOCAL_DIR_MODE_BITS);
         if (err == -1) {
             goto out;
@@ -334,8 +334,8 @@ static int local_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
             serrno = errno;
             goto err_end;
         }
-    } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
-               (fs_ctx->fs_sm == SM_NONE)) {
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
         err = mkdir(rpath(fs_ctx, path, buffer), credp->fc_mode);
         if (err == -1) {
             goto out;
@@ -363,7 +363,7 @@ static int local_fstat(FsContext *fs_ctx, int fd, struct stat *stbuf)
     if (err) {
         return err;
     }
-    if (fs_ctx->fs_sm == SM_MAPPED) {
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         /* Actual credentials are part of extended attrs */
         uid_t tmp_uid;
         gid_t tmp_gid;
@@ -401,7 +401,7 @@ static int local_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name,
     path = fullname.data;
 
     /* Determine the security model */
-    if (fs_ctx->fs_sm == SM_MAPPED) {
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         fd = open(rpath(fs_ctx, path, buffer), flags, SM_LOCAL_MODE_BITS);
         if (fd == -1) {
             err = fd;
@@ -414,8 +414,8 @@ static int local_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name,
             serrno = errno;
             goto err_end;
         }
-    } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
-               (fs_ctx->fs_sm == SM_NONE)) {
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
         fd = open(rpath(fs_ctx, path, buffer), flags, credp->fc_mode);
         if (fd == -1) {
             err = fd;
@@ -454,7 +454,7 @@ static int local_symlink(FsContext *fs_ctx, const char *oldpath,
     newpath = fullname.data;
 
     /* Determine the security model */
-    if (fs_ctx->fs_sm == SM_MAPPED) {
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         int fd;
         ssize_t oldpath_size, write_size;
         fd = open(rpath(fs_ctx, newpath, buffer), O_CREAT|O_EXCL|O_RDWR,
@@ -483,8 +483,8 @@ static int local_symlink(FsContext *fs_ctx, const char *oldpath,
             serrno = errno;
             goto err_end;
         }
-    } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
-               (fs_ctx->fs_sm == SM_NONE)) {
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
         err = symlink(oldpath, rpath(fs_ctx, newpath, buffer));
         if (err) {
             goto out;
@@ -496,7 +496,7 @@ static int local_symlink(FsContext *fs_ctx, const char *oldpath,
              * If we fail to change ownership and if we are
              * using security model none. Ignore the error
              */
-            if (fs_ctx->fs_sm != SM_NONE) {
+            if ((fs_ctx->export_flags & V9FS_SEC_MASK) != V9FS_SM_NONE) {
                 serrno = errno;
                 goto err_end;
             } else
@@ -551,13 +551,13 @@ static int local_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
     char *path = fs_path->data;
 
     if ((credp->fc_uid == -1 && credp->fc_gid == -1) ||
-            (fs_ctx->fs_sm == SM_PASSTHROUGH)) {
+            (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH)) {
         return lchown(rpath(fs_ctx, path, buffer), credp->fc_uid,
                 credp->fc_gid);
-    } else if (fs_ctx->fs_sm == SM_MAPPED) {
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
         return local_set_xattr(rpath(fs_ctx, path, buffer), credp);
-    } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
-               (fs_ctx->fs_sm == SM_NONE)) {
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
         return lchown(rpath(fs_ctx, path, buffer), credp->fc_uid,
                 credp->fc_gid);
     }