Add qemu 2.4.0
[kvmfornfv.git] / qemu / hw / 9pfs / cofs.c
diff --git a/qemu/hw/9pfs/cofs.c b/qemu/hw/9pfs/cofs.c
new file mode 100644 (file)
index 0000000..42ee614
--- /dev/null
@@ -0,0 +1,364 @@
+
+/*
+ * Virtio 9p backend
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ *  Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "fsdev/qemu-fsdev.h"
+#include "qemu/thread.h"
+#include "block/coroutine.h"
+#include "virtio-9p-coth.h"
+
+static ssize_t __readlink(V9fsState *s, V9fsPath *path, V9fsString *buf)
+{
+    ssize_t len, maxlen = PATH_MAX;
+
+    buf->data = g_malloc(PATH_MAX);
+    for(;;) {
+        len = s->ops->readlink(&s->ctx, path, buf->data, maxlen);
+        if (len < 0) {
+            g_free(buf->data);
+            buf->data = NULL;
+            buf->size = 0;
+            break;
+        } else if (len == maxlen) {
+            /*
+             * We dodn't have space to put the NULL or we have more
+             * to read. Increase the size and try again
+             */
+            maxlen *= 2;
+            g_free(buf->data);
+            buf->data = g_malloc(maxlen);
+            continue;
+        }
+        /*
+         * Null terminate the readlink output
+         */
+        buf->data[len] = '\0';
+        buf->size = len;
+        break;
+    }
+    return len;
+}
+
+int v9fs_co_readlink(V9fsPDU *pdu, V9fsPath *path, V9fsString *buf)
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = __readlink(s, path, buf);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+int v9fs_co_statfs(V9fsPDU *pdu, V9fsPath *path, struct statfs *stbuf)
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->statfs(&s->ctx, path, stbuf);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+int v9fs_co_chmod(V9fsPDU *pdu, V9fsPath *path, mode_t mode)
+{
+    int err;
+    FsCred cred;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    cred_init(&cred);
+    cred.fc_mode = mode;
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->chmod(&s->ctx, path, &cred);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+int v9fs_co_utimensat(V9fsPDU *pdu, V9fsPath *path,
+                      struct timespec times[2])
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->utimensat(&s->ctx, path, times);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+int v9fs_co_chown(V9fsPDU *pdu, V9fsPath *path, uid_t uid, gid_t gid)
+{
+    int err;
+    FsCred cred;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    cred_init(&cred);
+    cred.fc_uid = uid;
+    cred.fc_gid = gid;
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->chown(&s->ctx, path, &cred);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+int v9fs_co_truncate(V9fsPDU *pdu, V9fsPath *path, off_t size)
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->truncate(&s->ctx, path, size);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+int v9fs_co_mknod(V9fsPDU *pdu, 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;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    cred_init(&cred);
+    cred.fc_uid  = uid;
+    cred.fc_gid  = gid;
+    cred.fc_mode = mode;
+    cred.fc_rdev = dev;
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->mknod(&s->ctx, &fidp->path, name->data, &cred);
+            if (err < 0) {
+                err = -errno;
+            } else {
+                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);
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+/* Only works with path name based fid */
+int v9fs_co_remove(V9fsPDU *pdu, V9fsPath *path)
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->remove(&s->ctx, path->data);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+int v9fs_co_unlinkat(V9fsPDU *pdu, V9fsPath *path, V9fsString *name, int flags)
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->unlinkat(&s->ctx, path, name->data, flags);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    v9fs_path_unlock(s);
+    return err;
+}
+
+/* Only work with path name based fid */
+int v9fs_co_rename(V9fsPDU *pdu, V9fsPath *oldpath, V9fsPath *newpath)
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->rename(&s->ctx, oldpath->data, newpath->data);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    return err;
+}
+
+int v9fs_co_renameat(V9fsPDU *pdu, V9fsPath *olddirpath, V9fsString *oldname,
+                     V9fsPath *newdirpath, V9fsString *newname)
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    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(V9fsPDU *pdu, V9fsFidState *dfidp, V9fsString *name,
+                    const char *oldpath, gid_t gid, struct stat *stbuf)
+{
+    int err;
+    FsCred cred;
+    V9fsPath path;
+    V9fsState *s = pdu->s;
+
+    if (v9fs_request_cancelled(pdu)) {
+        return -EINTR;
+    }
+    cred_init(&cred);
+    cred.fc_uid = dfidp->uid;
+    cred.fc_gid = gid;
+    cred.fc_mode = 0777;
+    v9fs_path_read_lock(s);
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->symlink(&s->ctx, oldpath, &dfidp->path,
+                                  name->data, &cred);
+            if (err < 0) {
+                err = -errno;
+            } else {
+                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);
+            }
+        });
+    v9fs_path_unlock(s);
+    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(V9fsPDU *pdu, V9fsPath *dirpath,
+                         const char *name, V9fsPath *path)
+{
+    int err;
+    V9fsState *s = pdu->s;
+
+    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
+        err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
+        if (err < 0) {
+            err = -errno;
+        }
+    } else {
+        if (v9fs_request_cancelled(pdu)) {
+            return -EINTR;
+        }
+        v9fs_co_run_in_worker(
+            {
+                err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
+                if (err < 0) {
+                    err = -errno;
+                }
+            });
+    }
+    return err;
+}