hw/9pfs: Move fid pathname tracking to seperate data type.

This enables us to add handles to track fids later. The
V9fsPath added is similar to V9fsString except that the
size include the NULL byte also.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

fsdev/file-op-9p.h

@@ -57,43 +57,53 @@ typedef struct FsContext
     struct xattr_operations **xops;
 } FsContext;
 
+typedef struct V9fsPath {
+    int16_t size;
+    char *data;
+} V9fsPath;
+
 void cred_init(FsCred *);
 
 typedef struct FileOperations
 {
-    int (*lstat)(FsContext *, const char *, struct stat *);
-    ssize_t (*readlink)(FsContext *, const char *, char *, size_t);
-    int (*chmod)(FsContext *, const char *, FsCred *);
-    int (*chown)(FsContext *, const char *, FsCred *);
-    int (*mknod)(FsContext *, const char *, FsCred *);
-    int (*utimensat)(FsContext *, const char *, const struct timespec *);
+    int (*lstat)(FsContext *, V9fsPath *, struct stat *);
+    ssize_t (*readlink)(FsContext *, V9fsPath *, char *, size_t);
+    int (*chmod)(FsContext *, V9fsPath *, FsCred *);
+    int (*chown)(FsContext *, V9fsPath *, FsCred *);
+    int (*mknod)(FsContext *, V9fsPath *, const char *, FsCred *);
+    int (*utimensat)(FsContext *, V9fsPath *, const struct timespec *);
     int (*remove)(FsContext *, const char *);
-    int (*symlink)(FsContext *, const char *, const char *, FsCred *);
-    int (*link)(FsContext *, const char *, const char *);
+    int (*symlink)(FsContext *, const char *, V9fsPath *,
+                   const char *, FsCred *);
+    int (*link)(FsContext *, V9fsPath *, V9fsPath *, const char *);
     int (*setuid)(FsContext *, uid_t);
     int (*close)(FsContext *, int);
     int (*closedir)(FsContext *, DIR *);
-    DIR *(*opendir)(FsContext *, const char *);
-    int (*open)(FsContext *, const char *, int);
-    int (*open2)(FsContext *, const char *, int, FsCred *);
+    DIR *(*opendir)(FsContext *, V9fsPath *);
+    int (*open)(FsContext *, V9fsPath *, int);
+    int (*open2)(FsContext *, V9fsPath *, const char *, int, FsCred *);
     void (*rewinddir)(FsContext *, DIR *);
     off_t (*telldir)(FsContext *, DIR *);
     int (*readdir_r)(FsContext *, DIR *, struct dirent *, struct dirent **);
     void (*seekdir)(FsContext *, DIR *, off_t);
     ssize_t (*preadv)(FsContext *, int, const struct iovec *, int, off_t);
     ssize_t (*pwritev)(FsContext *, int, const struct iovec *, int, off_t);
-    int (*mkdir)(FsContext *, const char *, FsCred *);
+    int (*mkdir)(FsContext *, V9fsPath *, const char *, FsCred *);
     int (*fstat)(FsContext *, int, struct stat *);
     int (*rename)(FsContext *, const char *, const char *);
-    int (*truncate)(FsContext *, const char *, off_t);
+    int (*truncate)(FsContext *, V9fsPath *, off_t);
     int (*fsync)(FsContext *, int, int);
-    int (*statfs)(FsContext *s, const char *path, struct statfs *stbuf);
-    ssize_t (*lgetxattr)(FsContext *, const char *,
+    int (*statfs)(FsContext *s, V9fsPath *path, struct statfs *stbuf);
+    ssize_t (*lgetxattr)(FsContext *, V9fsPath *,
                          const char *, void *, size_t);
-    ssize_t (*llistxattr)(FsContext *, const char *, void *, size_t);
-    int (*lsetxattr)(FsContext *, const char *,
+    ssize_t (*llistxattr)(FsContext *, V9fsPath *, void *, size_t);
+    int (*lsetxattr)(FsContext *, V9fsPath *,
                      const char *, void *, size_t, int);
-    int (*lremovexattr)(FsContext *, const char *, const char *);
+    int (*lremovexattr)(FsContext *, V9fsPath *, const char *);
+    int (*name_to_path)(FsContext *, V9fsPath *, const char *, V9fsPath *);
+    int (*renameat)(FsContext *ctx, V9fsPath *olddir, const char *old_name,
+                    V9fsPath *newdir, const char *new_name);
+    int (*unlinkat)(FsContext *ctx, V9fsPath *dir, const char *name, int flags);
     void *opaque;
 } FileOperations;
 

hw/9pfs/codir.c

@@ -70,29 +70,31 @@ int v9fs_co_mkdir(V9fsState *s, V9fsFidState *fidp, V9fsString *name,
 {
     int err;
     FsCred cred;
-    V9fsString fullname;
+    V9fsPath path;
 
     cred_init(&cred);
     cred.fc_mode = mode;
     cred.fc_uid = uid;
     cred.fc_gid = gid;
-    v9fs_string_init(&fullname);
     qemu_co_rwlock_rdlock(&s->rename_lock);
-    v9fs_string_sprintf(&fullname, "%s/%s", fidp->path.data, name->data);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->mkdir(&s->ctx, fullname.data, &cred);
+            err = s->ops->mkdir(&s->ctx, &fidp->path, name->data,  &cred);
             if (err < 0) {
                 err = -errno;
             } else {
-                err = s->ops->lstat(&s->ctx, fullname.data, stbuf);
-                if (err < 0) {
-                    err = -errno;
+                v9fs_path_init(&path);
+                err = v9fs_name_to_path(s, &fidp->path, name->data, &path);
+                if (!err) {
+                    err = s->ops->lstat(&s->ctx, &path, stbuf);
+                    if (err < 0) {
+                        err = -errno;
+                    }
                 }
+                v9fs_path_free(&path);
             }
         });
     qemu_co_rwlock_unlock(&s->rename_lock);
-    v9fs_string_free(&fullname);
     return err;
 }
 
@@ -103,7 +105,7 @@ int v9fs_co_opendir(V9fsState *s, V9fsFidState *fidp)
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            fidp->fs.dir = s->ops->opendir(&s->ctx, fidp->path.data);
+            fidp->fs.dir = s->ops->opendir(&s->ctx, &fidp->path);
             if (!fidp->fs.dir) {
                 err = -errno;
             } else {

hw/9pfs/cofile.c

@@ -17,14 +17,14 @@
 #include "qemu-coroutine.h"
 #include "virtio-9p-coth.h"
 
-int v9fs_co_lstat(V9fsState *s, V9fsString *path, struct stat *stbuf)
+int v9fs_co_lstat(V9fsState *s, V9fsPath *path, struct stat *stbuf)
 {
     int err;
 
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->lstat(&s->ctx, path->data, stbuf);
+            err = s->ops->lstat(&s->ctx, path, stbuf);
             if (err < 0) {
                 err = -errno;
             }
@@ -54,7 +54,7 @@ int v9fs_co_open(V9fsState *s, V9fsFidState *fidp, int flags)
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            fidp->fs.fd = s->ops->open(&s->ctx, fidp->path.data, flags);
+            fidp->fs.fd = s->ops->open(&s->ctx, &fidp->path, flags);
             if (fidp->fs.fd == -1) {
                 err = -errno;
             } else {
@@ -76,33 +76,40 @@ int v9fs_co_open2(V9fsState *s, V9fsFidState *fidp, V9fsString *name, gid_t gid,
 {
     int err;
     FsCred cred;
-    V9fsString fullname;
+    V9fsPath path;
+
 
     cred_init(&cred);
     cred.fc_mode = mode & 07777;
     cred.fc_uid = fidp->uid;
     cred.fc_gid = gid;
-    v9fs_string_init(&fullname);
     /*
      * Hold the directory fid lock so that directory path name
      * don't change. Read lock is fine because this fid cannot
      * be used by any other operation.
      */
     qemu_co_rwlock_rdlock(&s->rename_lock);
-    v9fs_string_sprintf(&fullname, "%s/%s", fidp->path.data, name->data);
     v9fs_co_run_in_worker(
         {
-            fidp->fs.fd = s->ops->open2(&s->ctx, fullname.data, flags, &cred);
+            fidp->fs.fd = s->ops->open2(&s->ctx, &fidp->path,
+                                        name->data, flags, &cred);
             if (fidp->fs.fd == -1) {
                 err = -errno;
             } else {
-                err = s->ops->lstat(&s->ctx, fullname.data, stbuf);
-                if (err < 0) {
-                    err = -errno;
-                    err = s->ops->close(&s->ctx, fidp->fs.fd);
+                v9fs_path_init(&path);
+                err = v9fs_name_to_path(s, &fidp->path, name->data, &path);
+                if (!err) {
+                    err = s->ops->lstat(&s->ctx, &path, stbuf);
+                    if (err < 0) {
+                        err = -errno;
+                        s->ops->close(&s->ctx, fidp->fs.fd);
+                    } else {
+                        v9fs_path_copy(&fidp->path, &path);
+                    }
                 } else {
-                    v9fs_string_copy(&fidp->path, &fullname);
+                    s->ops->close(&s->ctx, fidp->fs.fd);
                 }
+                v9fs_path_free(&path);
             }
         });
     qemu_co_rwlock_unlock(&s->rename_lock);
@@ -112,7 +119,6 @@ int v9fs_co_open2(V9fsState *s, V9fsFidState *fidp, V9fsString *name, gid_t gid,
             v9fs_reclaim_fd(s);
         }
     }
-    v9fs_string_free(&fullname);
     return err;
 }
 
@@ -149,14 +155,16 @@ int v9fs_co_fsync(V9fsState *s, V9fsFidState *fidp, int datasync)
     return err;
 }
 
-int v9fs_co_link(V9fsState *s, V9fsString *oldpath, V9fsString *newpath)
+int v9fs_co_link(V9fsState *s, V9fsFidState *oldfid,
+                 V9fsFidState *newdirfid, V9fsString *name)
 {
     int err;
 
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->link(&s->ctx, oldpath->data, newpath->data);
+            err = s->ops->link(&s->ctx, &oldfid->path,
+                               &newdirfid->path, name->data);
             if (err < 0) {
                 err = -errno;
             }

hw/9pfs/cofs.c

@@ -17,7 +17,7 @@
 #include "qemu-coroutine.h"
 #include "virtio-9p-coth.h"
 
-int v9fs_co_readlink(V9fsState *s, V9fsString *path, V9fsString *buf)
+int v9fs_co_readlink(V9fsState *s, V9fsPath *path, V9fsString *buf)
 {
     int err;
     ssize_t len;
@@ -27,7 +27,7 @@ int v9fs_co_readlink(V9fsState *s, V9fsString *path, V9fsString *buf)
 
     v9fs_co_run_in_worker(
         {
-            len = s->ops->readlink(&s->ctx, path->data,
+            len = s->ops->readlink(&s->ctx, path,
                                    buf->data, PATH_MAX - 1);
             if (len > -1) {
                 buf->size = len;
@@ -46,14 +46,14 @@ int v9fs_co_readlink(V9fsState *s, V9fsString *path, V9fsString *buf)
     return err;
 }
 
-int v9fs_co_statfs(V9fsState *s, V9fsString *path, struct statfs *stbuf)
+int v9fs_co_statfs(V9fsState *s, V9fsPath *path, struct statfs *stbuf)
 {
     int err;
 
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->statfs(&s->ctx, path->data, stbuf);
+            err = s->ops->statfs(&s->ctx, path, stbuf);
             if (err < 0) {
                 err = -errno;
             }
@@ -62,7 +62,7 @@ int v9fs_co_statfs(V9fsState *s, V9fsString *path, struct statfs *stbuf)
     return err;
 }
 
-int v9fs_co_chmod(V9fsState *s, V9fsString *path, mode_t mode)
+int v9fs_co_chmod(V9fsState *s, V9fsPath *path, mode_t mode)
 {
     int err;
     FsCred cred;
@@ -72,7 +72,7 @@ int v9fs_co_chmod(V9fsState *s, V9fsString *path, mode_t mode)
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->chmod(&s->ctx, path->data, &cred);
+            err = s->ops->chmod(&s->ctx, path, &cred);
             if (err < 0) {
                 err = -errno;
             }
@@ -81,7 +81,7 @@ int v9fs_co_chmod(V9fsState *s, V9fsString *path, mode_t mode)
     return err;
 }
 
-int v9fs_co_utimensat(V9fsState *s, V9fsString *path,
+int v9fs_co_utimensat(V9fsState *s, V9fsPath *path,
                       struct timespec times[2])
 {
     int err;
@@ -89,7 +89,7 @@ int v9fs_co_utimensat(V9fsState *s, V9fsString *path,
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->utimensat(&s->ctx, path->data, times);
+            err = s->ops->utimensat(&s->ctx, path, times);
             if (err < 0) {
                 err = -errno;
             }
@@ -98,7 +98,7 @@ int v9fs_co_utimensat(V9fsState *s, V9fsString *path,
     return err;
 }
 
-int v9fs_co_chown(V9fsState *s, V9fsString *path, uid_t uid, gid_t gid)
+int v9fs_co_chown(V9fsState *s, V9fsPath *path, uid_t uid, gid_t gid)
 {
     int err;
     FsCred cred;
@@ -109,7 +109,7 @@ int v9fs_co_chown(V9fsState *s, V9fsString *path, uid_t uid, gid_t gid)
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->chown(&s->ctx, path->data, &cred);
+            err = s->ops->chown(&s->ctx, path, &cred);
             if (err < 0) {
                 err = -errno;
             }
@@ -118,14 +118,14 @@ int v9fs_co_chown(V9fsState *s, V9fsString *path, uid_t uid, gid_t gid)
     return err;
 }
 
-int v9fs_co_truncate(V9fsState *s, V9fsString *path, off_t size)
+int v9fs_co_truncate(V9fsState *s, V9fsPath *path, off_t size)
 {
     int err;
 
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->truncate(&s->ctx, path->data, size);
+            err = s->ops->truncate(&s->ctx, path, size);
             if (err < 0) {
                 err = -errno;
             }
@@ -138,35 +138,38 @@ int v9fs_co_mknod(V9fsState *s, V9fsFidState *fidp, V9fsString *name, uid_t uid,
                   gid_t gid, dev_t dev, mode_t mode, struct stat *stbuf)
 {
     int err;
+    V9fsPath path;
     FsCred cred;
-    V9fsString fullname;
 
     cred_init(&cred);
     cred.fc_uid  = uid;
     cred.fc_gid  = gid;
     cred.fc_mode = mode;
     cred.fc_rdev = dev;
-    v9fs_string_init(&fullname);
     qemu_co_rwlock_rdlock(&s->rename_lock);
-    v9fs_string_sprintf(&fullname, "%s/%s", fidp->path.data, name->data);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->mknod(&s->ctx, fullname.data, &cred);
+            err = s->ops->mknod(&s->ctx, &fidp->path, name->data, &cred);
             if (err < 0) {
                 err = -errno;
             } else {
-                err = s->ops->lstat(&s->ctx, fullname.data, stbuf);
-                if (err < 0) {
-                    err = -errno;
+                v9fs_path_init(&path);
+                err = v9fs_name_to_path(s, &fidp->path, name->data, &path);
+                if (!err) {
+                    err = s->ops->lstat(&s->ctx, &path, stbuf);
+                    if (err < 0) {
+                        err = -errno;
+                    }
                 }
+                v9fs_path_free(&path);
             }
         });
     qemu_co_rwlock_unlock(&s->rename_lock);
-    v9fs_string_free(&fullname);
     return err;
 }
 
-int v9fs_co_remove(V9fsState *s, V9fsString *path)
+/* Only works with path name based fid */
+int v9fs_co_remove(V9fsState *s, V9fsPath *path)
 {
     int err;
 
@@ -182,7 +185,24 @@ int v9fs_co_remove(V9fsState *s, V9fsString *path)
     return err;
 }
 
-int v9fs_co_rename(V9fsState *s, V9fsString *oldpath, V9fsString *newpath)
+int v9fs_co_unlinkat(V9fsState *s, V9fsPath *path, V9fsString *name, int flags)
+{
+    int err;
+
+    qemu_co_rwlock_rdlock(&s->rename_lock);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->unlinkat(&s->ctx, path, name->data, flags);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    qemu_co_rwlock_unlock(&s->rename_lock);
+    return err;
+}
+
+/* Only work with path name based fid */
+int v9fs_co_rename(V9fsState *s, V9fsPath *oldpath, V9fsPath *newpath)
 {
     int err;
 
@@ -196,34 +216,68 @@ int v9fs_co_rename(V9fsState *s, V9fsString *oldpath, V9fsString *newpath)
     return err;
 }
 
+int v9fs_co_renameat(V9fsState *s, V9fsPath *olddirpath, V9fsString *oldname,
+                     V9fsPath *newdirpath, V9fsString *newname)
+{
+    int err;
+
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->renameat(&s->ctx, olddirpath, oldname->data,
+                                   newdirpath, newname->data);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    return err;
+}
+
 int v9fs_co_symlink(V9fsState *s, V9fsFidState *dfidp, V9fsString *name,
                     const char *oldpath, gid_t gid, struct stat *stbuf)
 {
     int err;
     FsCred cred;
-    V9fsString fullname;
+    V9fsPath path;
 
 
     cred_init(&cred);
     cred.fc_uid = dfidp->uid;
     cred.fc_gid = gid;
     cred.fc_mode = 0777;
-    v9fs_string_init(&fullname);
     qemu_co_rwlock_rdlock(&s->rename_lock);
-    v9fs_string_sprintf(&fullname, "%s/%s", dfidp->path.data, name->data);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->symlink(&s->ctx, oldpath, fullname.data, &cred);
+            err = s->ops->symlink(&s->ctx, oldpath, &dfidp->path,
+                                  name->data, &cred);
             if (err < 0) {
                 err = -errno;
             } else {
-                err = s->ops->lstat(&s->ctx, fullname.data, stbuf);
-                if (err < 0) {
-                    err = -errno;
+                v9fs_path_init(&path);
+                err = v9fs_name_to_path(s, &dfidp->path, name->data, &path);
+                if (!err) {
+                    err = s->ops->lstat(&s->ctx, &path, stbuf);
+                    if (err < 0) {
+                        err = -errno;
+                    }
                 }
+                v9fs_path_free(&path);
             }
         });
     qemu_co_rwlock_unlock(&s->rename_lock);
-    v9fs_string_free(&fullname);
+    return err;
+}
+
+/*
+ * For path name based fid we don't block. So we can
+ * directly call the fs driver ops.
+ */
+int v9fs_co_name_to_path(V9fsState *s, V9fsPath *dirpath,
+                         const char *name, V9fsPath *path)
+{
+    int err;
+    err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
+    if (err < 0) {
+        err = -errno;
+    }
     return err;
 }

hw/9pfs/coxattr.c

@@ -17,14 +17,14 @@
 #include "qemu-coroutine.h"
 #include "virtio-9p-coth.h"
 
-int v9fs_co_llistxattr(V9fsState *s, V9fsString *path, void *value, size_t size)
+int v9fs_co_llistxattr(V9fsState *s, V9fsPath *path, void *value, size_t size)
 {
     int err;
 
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->llistxattr(&s->ctx, path->data, value, size);
+            err = s->ops->llistxattr(&s->ctx, path, value, size);
             if (err < 0) {
                 err = -errno;
             }
@@ -33,7 +33,7 @@ int v9fs_co_llistxattr(V9fsState *s, V9fsString *path, void *value, size_t size)
     return err;
 }
 
-int v9fs_co_lgetxattr(V9fsState *s, V9fsString *path,
+int v9fs_co_lgetxattr(V9fsState *s, V9fsPath *path,
                       V9fsString *xattr_name,
                       void *value, size_t size)
 {
@@ -42,7 +42,7 @@ int v9fs_co_lgetxattr(V9fsState *s, V9fsString *path,
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->lgetxattr(&s->ctx, path->data,
+            err = s->ops->lgetxattr(&s->ctx, path,
                                     xattr_name->data,
                                     value, size);
             if (err < 0) {
@@ -53,7 +53,7 @@ int v9fs_co_lgetxattr(V9fsState *s, V9fsString *path,
     return err;
 }
 
-int v9fs_co_lsetxattr(V9fsState *s, V9fsString *path,
+int v9fs_co_lsetxattr(V9fsState *s, V9fsPath *path,
                       V9fsString *xattr_name, void *value,
                       size_t size, int flags)
 {
@@ -62,7 +62,7 @@ int v9fs_co_lsetxattr(V9fsState *s, V9fsString *path,
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->lsetxattr(&s->ctx, path->data,
+            err = s->ops->lsetxattr(&s->ctx, path,
                                     xattr_name->data, value,
                                     size, flags);
             if (err < 0) {
@@ -73,7 +73,7 @@ int v9fs_co_lsetxattr(V9fsState *s, V9fsString *path,
     return err;
 }
 
-int v9fs_co_lremovexattr(V9fsState *s, V9fsString *path,
+int v9fs_co_lremovexattr(V9fsState *s, V9fsPath *path,
                          V9fsString *xattr_name)
 {
     int err;
@@ -81,8 +81,7 @@ int v9fs_co_lremovexattr(V9fsState *s, V9fsString *path,
     qemu_co_rwlock_rdlock(&s->rename_lock);
     v9fs_co_run_in_worker(
         {
-            err = s->ops->lremovexattr(&s->ctx, path->data,
-                                       xattr_name->data);
+            err = s->ops->lremovexattr(&s->ctx, path, xattr_name->data);
             if (err < 0) {
                 err = -errno;
             }

hw/9pfs/virtio-9p-coth.h

@@ -56,43 +56,49 @@ typedef struct V9fsThPool {
 
 extern void co_run_in_worker_bh(void *);
 extern int v9fs_init_worker_threads(void);
-extern int v9fs_co_readlink(V9fsState *, V9fsString *, V9fsString *);
+extern int v9fs_co_readlink(V9fsState *, V9fsPath *, V9fsString *);
 extern int v9fs_co_readdir_r(V9fsState *, V9fsFidState *,
                            struct dirent *, struct dirent **result);
 extern off_t v9fs_co_telldir(V9fsState *, V9fsFidState *);
 extern void v9fs_co_seekdir(V9fsState *, V9fsFidState *, off_t);
 extern void v9fs_co_rewinddir(V9fsState *, V9fsFidState *);
-extern int v9fs_co_statfs(V9fsState *, V9fsString *, struct statfs *);
-extern int v9fs_co_lstat(V9fsState *, V9fsString *, struct stat *);
-extern int v9fs_co_chmod(V9fsState *, V9fsString *, mode_t);
-extern int v9fs_co_utimensat(V9fsState *, V9fsString *, struct timespec [2]);
-extern int v9fs_co_chown(V9fsState *, V9fsString *, uid_t, gid_t);
-extern int v9fs_co_truncate(V9fsState *, V9fsString *, off_t);
-extern int v9fs_co_llistxattr(V9fsState *, V9fsString *, void *, size_t);
-extern int v9fs_co_lgetxattr(V9fsState *, V9fsString *,
+extern int v9fs_co_statfs(V9fsState *, V9fsPath *, struct statfs *);
+extern int v9fs_co_lstat(V9fsState *, V9fsPath *, struct stat *);
+extern int v9fs_co_chmod(V9fsState *, V9fsPath *, mode_t);
+extern int v9fs_co_utimensat(V9fsState *, V9fsPath *, struct timespec [2]);
+extern int v9fs_co_chown(V9fsState *, V9fsPath *, uid_t, gid_t);
+extern int v9fs_co_truncate(V9fsState *, V9fsPath *, off_t);
+extern int v9fs_co_llistxattr(V9fsState *, V9fsPath *, void *, size_t);
+extern int v9fs_co_lgetxattr(V9fsState *, V9fsPath *,
                              V9fsString *, void *, size_t);
 extern int v9fs_co_mknod(V9fsState *, V9fsFidState *, V9fsString *, uid_t,
                          gid_t, dev_t, mode_t, struct stat *);
 extern int v9fs_co_mkdir(V9fsState *, V9fsFidState *, V9fsString *,
                          mode_t, uid_t, gid_t, struct stat *);
-extern int v9fs_co_remove(V9fsState *, V9fsString *);
-extern int v9fs_co_rename(V9fsState *, V9fsString *, V9fsString *);
+extern int v9fs_co_remove(V9fsState *, V9fsPath *);
+extern int v9fs_co_rename(V9fsState *, V9fsPath *, V9fsPath *);
+extern int v9fs_co_unlinkat(V9fsState *, V9fsPath *, V9fsString *, int flags);
+extern int v9fs_co_renameat(V9fsState *, V9fsPath *, V9fsString *,
+                            V9fsPath *, V9fsString *);
 extern int v9fs_co_fstat(V9fsState *, int, struct stat *);
 extern int v9fs_co_opendir(V9fsState *, V9fsFidState *);
 extern int v9fs_co_open(V9fsState *, V9fsFidState *, int);
 extern int v9fs_co_open2(V9fsState *, V9fsFidState *, V9fsString *,
                          gid_t, int, int, struct stat *);
-extern int v9fs_co_lsetxattr(V9fsState *, V9fsString *, V9fsString *,
+extern int v9fs_co_lsetxattr(V9fsState *, V9fsPath *, V9fsString *,
                              void *, size_t, int);
-extern int v9fs_co_lremovexattr(V9fsState *, V9fsString *, V9fsString *);
+extern int v9fs_co_lremovexattr(V9fsState *, V9fsPath *, V9fsString *);
 extern int v9fs_co_closedir(V9fsState *, DIR *);
 extern int v9fs_co_close(V9fsState *, int);
 extern int v9fs_co_fsync(V9fsState *, V9fsFidState *, int);
 extern int v9fs_co_symlink(V9fsState *, V9fsFidState *, V9fsString *,
                            const char *, gid_t, struct stat *);
-extern int v9fs_co_link(V9fsState *, V9fsString *, V9fsString *);
+extern int v9fs_co_link(V9fsState *, V9fsFidState *,
+                        V9fsFidState *, V9fsString *);
 extern int v9fs_co_pwritev(V9fsState *, V9fsFidState *,
                            struct iovec *, int, int64_t);
 extern int v9fs_co_preadv(V9fsState *, V9fsFidState *,
                           struct iovec *, int, int64_t);
+extern int v9fs_co_name_to_path(V9fsState *, V9fsPath *,
+                                const char *, V9fsPath *);
 #endif

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

@@ -22,10 +22,12 @@
 #include <attr/xattr.h>
 
 
-static int local_lstat(FsContext *fs_ctx, const char *path, struct stat *stbuf)
+static int local_lstat(FsContext *fs_ctx, V9fsPath *fs_path, struct stat *stbuf)
 {
     int err;
     char buffer[PATH_MAX];
+    char *path = fs_path->data;
+
     err =  lstat(rpath(fs_ctx, path, buffer), stbuf);
     if (err) {
         return err;
@@ -59,6 +61,7 @@ static int local_lstat(FsContext *fs_ctx, const char *path, struct stat *stbuf)
 static int local_set_xattr(const char *path, FsCred *credp)
 {
     int err;
+
     if (credp->fc_uid != -1) {
         err = setxattr(path, "user.virtfs.uid", &credp->fc_uid, sizeof(uid_t),
                 0);
@@ -91,9 +94,10 @@ static int local_set_xattr(const char *path, FsCred *credp)
 }
 
 static int local_post_create_passthrough(FsContext *fs_ctx, const char *path,
-        FsCred *credp)
+                                         FsCred *credp)
 {
     char buffer[PATH_MAX];
+
     if (chmod(rpath(fs_ctx, path, buffer), credp->fc_mode & 07777) < 0) {
         return -1;
     }
@@ -110,11 +114,13 @@ static int local_post_create_passthrough(FsContext *fs_ctx, const char *path,
     return 0;
 }
 
-static ssize_t local_readlink(FsContext *fs_ctx, const char *path,
-        char *buf, size_t bufsz)
+static ssize_t local_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
+                              char *buf, size_t bufsz)
 {
     ssize_t tsize = -1;
     char buffer[PATH_MAX];
+    char *path = fs_path->data;
+
     if (fs_ctx->fs_sm == SM_MAPPED) {
         int fd;
         fd = open(rpath(fs_ctx, path, buffer), O_RDONLY);
@@ -143,15 +149,19 @@ static int local_closedir(FsContext *ctx, DIR *dir)
     return closedir(dir);
 }
 
-static int local_open(FsContext *ctx, const char *path, int flags)
+static int local_open(FsContext *ctx, V9fsPath *fs_path, int flags)
 {
     char buffer[PATH_MAX];
+    char *path = fs_path->data;
+
     return open(rpath(ctx, path, buffer), flags);
 }
 
-static DIR *local_opendir(FsContext *ctx, const char *path)
+static DIR *local_opendir(FsContext *ctx, V9fsPath *fs_path)
 {
     char buffer[PATH_MAX];
+    char *path = fs_path->data;
+
     return opendir(rpath(ctx, path, buffer));
 }
 
@@ -166,7 +176,7 @@ static off_t local_telldir(FsContext *ctx, DIR *dir)
 }
 
 static int local_readdir_r(FsContext *ctx, DIR *dir, struct dirent *entry,
-                         struct dirent **result)
+                           struct dirent **result)
 {
     return readdir_r(dir, entry, result);
 }
@@ -192,7 +202,7 @@ static ssize_t local_preadv(FsContext *ctx, int fd, const struct iovec *iov,
 }
 
 static ssize_t local_pwritev(FsContext *ctx, int fd, const struct iovec *iov,
-                            int iovcnt, off_t offset)
+                             int iovcnt, off_t offset)
 {
 #ifdef CONFIG_PREADV
     return pwritev(fd, iov, iovcnt, offset);
@@ -206,9 +216,11 @@ static ssize_t local_pwritev(FsContext *ctx, int fd, const struct iovec *iov,
 #endif
 }
 
-static int local_chmod(FsContext *fs_ctx, const char *path, FsCred *credp)
+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) {
         return local_set_xattr(rpath(fs_ctx, path, buffer), credp);
     } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) ||
@@ -218,18 +230,25 @@ static int local_chmod(FsContext *fs_ctx, const char *path, FsCred *credp)
     return -1;
 }
 
-static int local_mknod(FsContext *fs_ctx, const char *path, FsCred *credp)
+static int local_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
+                       const char *name, FsCred *credp)
 {
+    char *path;
     int err = -1;
     int serrno = 0;
+    V9fsString fullname;
     char buffer[PATH_MAX];
 
+    v9fs_string_init(&fullname);
+    v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
+    path = fullname.data;
+
     /* Determine the security model */
     if (fs_ctx->fs_sm == SM_MAPPED) {
         err = mknod(rpath(fs_ctx, path, buffer),
                 SM_LOCAL_MODE_BITS|S_IFREG, 0);
         if (err == -1) {
-            return err;
+            goto out;
         }
         local_set_xattr(rpath(fs_ctx, path, buffer), credp);
         if (err == -1) {
@@ -241,7 +260,7 @@ static int local_mknod(FsContext *fs_ctx, const char *path, FsCred *credp)
         err = mknod(rpath(fs_ctx, path, buffer), credp->fc_mode,
                 credp->fc_rdev);
         if (err == -1) {
-            return err;
+            goto out;
         }
         err = local_post_create_passthrough(fs_ctx, path, credp);
         if (err == -1) {
@@ -249,25 +268,34 @@ static int local_mknod(FsContext *fs_ctx, const char *path, FsCred *credp)
             goto err_end;
         }
     }
-    return err;
+    goto out;
 
 err_end:
     remove(rpath(fs_ctx, path, buffer));
     errno = serrno;
+out:
+    v9fs_string_free(&fullname);
     return err;
 }
 
-static int local_mkdir(FsContext *fs_ctx, const char *path, FsCred *credp)
+static int local_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
+                       const char *name, FsCred *credp)
 {
+    char *path;
     int err = -1;
     int serrno = 0;
+    V9fsString fullname;
     char buffer[PATH_MAX];
 
+    v9fs_string_init(&fullname);
+    v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
+    path = fullname.data;
+
     /* Determine the security model */
     if (fs_ctx->fs_sm == SM_MAPPED) {
         err = mkdir(rpath(fs_ctx, path, buffer), SM_LOCAL_DIR_MODE_BITS);
         if (err == -1) {
-            return err;
+            goto out;
         }
         credp->fc_mode = credp->fc_mode|S_IFDIR;
         err = local_set_xattr(rpath(fs_ctx, path, buffer), credp);
@@ -279,7 +307,7 @@ static int local_mkdir(FsContext *fs_ctx, const char *path, FsCred *credp)
                (fs_ctx->fs_sm == SM_NONE)) {
         err = mkdir(rpath(fs_ctx, path, buffer), credp->fc_mode);
         if (err == -1) {
-            return err;
+            goto out;
         }
         err = local_post_create_passthrough(fs_ctx, path, credp);
         if (err == -1) {
@@ -287,11 +315,13 @@ static int local_mkdir(FsContext *fs_ctx, const char *path, FsCred *credp)
             goto err_end;
         }
     }
-    return err;
+    goto out;
 
 err_end:
     remove(rpath(fs_ctx, path, buffer));
     errno = serrno;
+out:
+    v9fs_string_free(&fullname);
     return err;
 }
 
@@ -325,19 +355,26 @@ static int local_fstat(FsContext *fs_ctx, int fd, struct stat *stbuf)
     return err;
 }
 
-static int local_open2(FsContext *fs_ctx, const char *path, int flags,
-        FsCred *credp)
+static int local_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name,
+                       int flags, FsCred *credp)
 {
+    char *path;
     int fd = -1;
     int err = -1;
     int serrno = 0;
+    V9fsString fullname;
     char buffer[PATH_MAX];
 
+    v9fs_string_init(&fullname);
+    v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
+    path = fullname.data;
+
     /* Determine the security model */
     if (fs_ctx->fs_sm == SM_MAPPED) {
         fd = open(rpath(fs_ctx, path, buffer), flags, SM_LOCAL_MODE_BITS);
         if (fd == -1) {
-            return fd;
+            err = fd;
+            goto out;
         }
         credp->fc_mode = credp->fc_mode|S_IFREG;
         /* Set cleint credentials in xattr */
@@ -350,7 +387,8 @@ static int local_open2(FsContext *fs_ctx, const char *path, int flags,
                (fs_ctx->fs_sm == SM_NONE)) {
         fd = open(rpath(fs_ctx, path, buffer), flags, credp->fc_mode);
         if (fd == -1) {
-            return fd;
+            err = fd;
+            goto out;
         }
         err = local_post_create_passthrough(fs_ctx, path, credp);
         if (err == -1) {
@@ -358,23 +396,32 @@ static int local_open2(FsContext *fs_ctx, const char *path, int flags,
             goto err_end;
         }
     }
-    return fd;
+    err = fd;
+    goto out;
 
 err_end:
     close(fd);
     remove(rpath(fs_ctx, path, buffer));
     errno = serrno;
+out:
+    v9fs_string_free(&fullname);
     return err;
 }
 
 
 static int local_symlink(FsContext *fs_ctx, const char *oldpath,
-        const char *newpath, FsCred *credp)
+                         V9fsPath *dir_path, const char *name, FsCred *credp)
 {
     int err = -1;
     int serrno = 0;
+    char *newpath;
+    V9fsString fullname;
     char buffer[PATH_MAX];
 
+    v9fs_string_init(&fullname);
+    v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
+    newpath = fullname.data;
+
     /* Determine the security model */
     if (fs_ctx->fs_sm == SM_MAPPED) {
         int fd;
@@ -382,7 +429,8 @@ static int local_symlink(FsContext *fs_ctx, const char *oldpath,
         fd = open(rpath(fs_ctx, newpath, buffer), O_CREAT|O_EXCL|O_RDWR,
                 SM_LOCAL_MODE_BITS);
         if (fd == -1) {
-            return fd;
+            err = fd;
+            goto out;
         }
         /* Write the oldpath (target) to the file. */
         oldpath_size = strlen(oldpath);
@@ -408,10 +456,10 @@ static int local_symlink(FsContext *fs_ctx, const char *oldpath,
                (fs_ctx->fs_sm == SM_NONE)) {
         err = symlink(oldpath, rpath(fs_ctx, newpath, buffer));
         if (err) {
-            return err;
+            goto out;
         }
         err = lchown(rpath(fs_ctx, newpath, buffer), credp->fc_uid,
-                credp->fc_gid);
+                     credp->fc_gid);
         if (err == -1) {
             /*
              * If we fail to change ownership and if we are
@@ -424,24 +472,37 @@ static int local_symlink(FsContext *fs_ctx, const char *oldpath,
                 err = 0;
         }
     }
-    return err;
+    goto out;
 
 err_end:
     remove(rpath(fs_ctx, newpath, buffer));
     errno = serrno;
+out:
+    v9fs_string_free(&fullname);
     return err;
 }
 
-static int local_link(FsContext *ctx, const char *oldpath, const char *newpath)
+static int local_link(FsContext *ctx, V9fsPath *oldpath,
+                      V9fsPath *dirpath, const char *name)
 {
+    int ret;
+    V9fsString newpath;
     char buffer[PATH_MAX], buffer1[PATH_MAX];
 
-    return link(rpath(ctx, oldpath, buffer), rpath(ctx, newpath, buffer1));
+    v9fs_string_init(&newpath);
+    v9fs_string_sprintf(&newpath, "%s/%s", dirpath->data, name);
+
+    ret = link(rpath(ctx, oldpath->data, buffer),
+               rpath(ctx, newpath.data, buffer1));
+    v9fs_string_free(&newpath);
+    return ret;
 }
 
-static int local_truncate(FsContext *ctx, const char *path, off_t size)
+static int local_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size)
 {
     char buffer[PATH_MAX];
+    char *path = fs_path->data;
+
     return truncate(rpath(ctx, path, buffer), size);
 }
 
@@ -453,9 +514,11 @@ static int local_rename(FsContext *ctx, const char *oldpath,
     return rename(rpath(ctx, oldpath, buffer), rpath(ctx, newpath, buffer1));
 }
 
-static int local_chown(FsContext *fs_ctx, const char *path, FsCred *credp)
+static int local_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
 {
     char buffer[PATH_MAX];
+    char *path = fs_path->data;
+
     if ((credp->fc_uid == -1 && credp->fc_gid == -1) ||
             (fs_ctx->fs_sm == SM_PASSTHROUGH)) {
         return lchown(rpath(fs_ctx, path, buffer), credp->fc_uid,
@@ -470,12 +533,14 @@ static int local_chown(FsContext *fs_ctx, const char *path, FsCred *credp)
     return -1;
 }
 
-static int local_utimensat(FsContext *s, const char *path,
+static int local_utimensat(FsContext *s, V9fsPath *fs_path,
                            const struct timespec *buf)
 {
     char buffer[PATH_MAX];
+    char *path = fs_path->data;
+
     return qemu_utimensat(AT_FDCWD, rpath(s, path, buffer), buf,
-            AT_SYMLINK_NOFOLLOW);
+                          AT_SYMLINK_NOFOLLOW);
 }
 
 static int local_remove(FsContext *ctx, const char *path)
@@ -493,36 +558,93 @@ static int local_fsync(FsContext *ctx, int fd, int datasync)
     }
 }
 
-static int local_statfs(FsContext *s, const char *path, struct statfs *stbuf)
+static int local_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *stbuf)
 {
     char buffer[PATH_MAX];
-   return statfs(rpath(s, path, buffer), stbuf);
+    char *path = fs_path->data;
+
+    return statfs(rpath(s, path, buffer), stbuf);
 }
 
-static ssize_t local_lgetxattr(FsContext *ctx, const char *path,
+static ssize_t local_lgetxattr(FsContext *ctx, V9fsPath *fs_path,
                                const char *name, void *value, size_t size)
 {
+    char *path = fs_path->data;
+
     return v9fs_get_xattr(ctx, path, name, value, size);
 }
 
-static ssize_t local_llistxattr(FsContext *ctx, const char *path,
+static ssize_t local_llistxattr(FsContext *ctx, V9fsPath *fs_path,
                                 void *value, size_t size)
 {
+    char *path = fs_path->data;
+
     return v9fs_list_xattr(ctx, path, value, size);
 }
 
-static int local_lsetxattr(FsContext *ctx, const char *path, const char *name,
+static int local_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name,
                            void *value, size_t size, int flags)
 {
+    char *path = fs_path->data;
+
     return v9fs_set_xattr(ctx, path, name, value, size, flags);
 }
 
-static int local_lremovexattr(FsContext *ctx,
-                              const char *path, const char *name)
+static int local_lremovexattr(FsContext *ctx, V9fsPath *fs_path,
+                              const char *name)
 {
+    char *path = fs_path->data;
+
     return v9fs_remove_xattr(ctx, path, name);
 }
 
+static int local_name_to_path(FsContext *ctx, V9fsPath *dir_path,
+                              const char *name, V9fsPath *target)
+{
+    if (dir_path) {
+        v9fs_string_sprintf((V9fsString *)target, "%s/%s",
+                            dir_path->data, name);
+    } else {
+        v9fs_string_sprintf((V9fsString *)target, "%s", name);
+    }
+    /* Bump the size for including terminating NULL */
+    target->size++;
+    return 0;
+}
+
+static int local_renameat(FsContext *ctx, V9fsPath *olddir,
+                          const char *old_name, V9fsPath *newdir,
+                          const char *new_name)
+{
+    int ret;
+    V9fsString old_full_name, new_full_name;
+
+    v9fs_string_init(&old_full_name);
+    v9fs_string_init(&new_full_name);
+
+    v9fs_string_sprintf(&old_full_name, "%s/%s", olddir->data, old_name);
+    v9fs_string_sprintf(&new_full_name, "%s/%s", newdir->data, new_name);
+
+    ret = local_rename(ctx, old_full_name.data, new_full_name.data);
+    v9fs_string_free(&old_full_name);
+    v9fs_string_free(&new_full_name);
+    return ret;
+}
+
+static int local_unlinkat(FsContext *ctx, V9fsPath *dir,
+                          const char *name, int flags)
+{
+    int ret;
+    V9fsString fullname;
+    char buffer[PATH_MAX];
+    v9fs_string_init(&fullname);
+
+    v9fs_string_sprintf(&fullname, "%s/%s", dir->data, name);
+    ret = remove(rpath(ctx, fullname.data, buffer));
+    v9fs_string_free(&fullname);
+
+    return ret;
+}
 
 FileOperations local_ops = {
     .lstat = local_lstat,
@@ -555,4 +677,7 @@ FileOperations local_ops = {
     .llistxattr = local_llistxattr,
     .lsetxattr = local_lsetxattr,
     .lremovexattr = local_lremovexattr,
+    .name_to_path = local_name_to_path,
+    .renameat  = local_renameat,
+    .unlinkat = local_unlinkat,
 };

hw/9pfs/virtio-9p.h

@@ -206,7 +206,7 @@ struct V9fsFidState
 {
     int fid_type;
     int32_t fid;
-    V9fsString path;
+    V9fsPath path;
     union {
         int fd;
         DIR *dir;
@@ -396,4 +396,9 @@ extern void v9fs_string_free(V9fsString *str);
 extern void v9fs_string_null(V9fsString *str);
 extern void v9fs_string_sprintf(V9fsString *str, const char *fmt, ...);
 extern void v9fs_string_copy(V9fsString *lhs, V9fsString *rhs);
+extern void v9fs_path_init(V9fsPath *path);
+extern void v9fs_path_free(V9fsPath *path);
+extern void v9fs_path_copy(V9fsPath *lhs, V9fsPath *rhs);
+extern int v9fs_name_to_path(V9fsState *s, V9fsPath *dirpath,
+                             const char *name, V9fsPath *path);
 #endif