diff options
author | Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> | 2011-08-02 11:35:54 +0530 |
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committer | Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> | 2011-09-22 21:38:53 +0530 |
commit | 5f5422258e1f50f871bafcc5bfb2b498f414a310 (patch) | |
tree | d2a3ff07b94f553d3afd2ff8e63bb91ab2ca20e5 /hw/9pfs | |
parent | bccacf6c7920ee46ec4063c4bd9469eb3ec4e253 (diff) |
hw/9pfs: Add handle based fs driver
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Diffstat (limited to 'hw/9pfs')
-rw-r--r-- | hw/9pfs/virtio-9p-handle.c | 611 |
1 files changed, 611 insertions, 0 deletions
diff --git a/hw/9pfs/virtio-9p-handle.c b/hw/9pfs/virtio-9p-handle.c new file mode 100644 index 0000000000..5c8b5ed471 --- /dev/null +++ b/hw/9pfs/virtio-9p-handle.c @@ -0,0 +1,611 @@ +/* + * Virtio 9p handle callback + * + * 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 "hw/virtio.h" +#include "virtio-9p.h" +#include "virtio-9p-xattr.h" +#include <arpa/inet.h> +#include <pwd.h> +#include <grp.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <attr/xattr.h> +#include <unistd.h> + +struct handle_data { + int mountfd; + int handle_bytes; +}; + +#if __GLIBC__ <= 2 && __GLIBC_MINOR__ < 14 +struct file_handle { + unsigned int handle_bytes; + int handle_type; + unsigned char handle[0]; +}; +#endif + +#ifndef AT_EMPTY_PATH +#define AT_EMPTY_PATH 0x1000 /* Allow empty relative pathname */ +#endif +#ifndef O_PATH +#define O_PATH 010000000 +#endif + +#ifndef __NR_name_to_handle_at +#if defined(__i386__) +#define __NR_name_to_handle_at 341 +#define __NR_open_by_handle_at 342 +#elif defined(__x86_64__) +#define __NR_name_to_handle_at 303 +#define __NR_open_by_handle_at 304 +#endif +#endif + +#ifdef __NR_name_to_handle_at +static inline int name_to_handle(int dirfd, const char *name, + struct file_handle *fh, int *mnt_id, int flags) +{ + return syscall(__NR_name_to_handle_at, dirfd, name, fh, mnt_id, flags); +} + +static inline int open_by_handle(int mountfd, const char *fh, int flags) +{ + return syscall(__NR_open_by_handle_at, mountfd, fh, flags); +} +#else +static inline int name_to_handle(int dirfd, const char *name, + struct file_handle *fh, int *mnt_id, int flags) +{ + errno = ENOSYS; + return -1; +} + +static inline int open_by_handle(int mountfd, const char *fh, int flags) +{ + errno = ENOSYS; + return -1; +} +#endif + +static int handle_update_file_cred(int dirfd, const char *name, FsCred *credp) +{ + int fd, ret; + fd = openat(dirfd, name, O_NONBLOCK | O_NOFOLLOW);; + if (fd < 0) { + return fd; + } + ret = fchmod(fd, credp->fc_mode & 07777); + if (ret < 0) { + goto err_out; + } + ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH); +err_out: + close(fd); + return ret; +} + + +static int handle_lstat(FsContext *fs_ctx, V9fsPath *fs_path, + struct stat *stbuf) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)fs_ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_PATH); + if (fd < 0) { + return fd; + } + ret = fstatat(fd, "", stbuf, AT_EMPTY_PATH); + close(fd); + return ret; +} + +static ssize_t handle_readlink(FsContext *fs_ctx, V9fsPath *fs_path, + char *buf, size_t bufsz) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)fs_ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_PATH); + if (fd < 0) { + return fd; + } + ret = readlinkat(fd, "", buf, bufsz); + close(fd); + return ret; +} + +static int handle_close(FsContext *ctx, int fd) +{ + return close(fd); +} + +static int handle_closedir(FsContext *ctx, DIR *dir) +{ + return closedir(dir); +} + +static int handle_open(FsContext *ctx, V9fsPath *fs_path, int flags) +{ + struct handle_data *data = (struct handle_data *)ctx->private; + + return open_by_handle(data->mountfd, fs_path->data, flags); +} + +static DIR *handle_opendir(FsContext *ctx, V9fsPath *fs_path) +{ + int fd; + fd = handle_open(ctx, fs_path, O_DIRECTORY); + if (fd < 0) { + return NULL; + } + return fdopendir(fd); +} + +static void handle_rewinddir(FsContext *ctx, DIR *dir) +{ + return rewinddir(dir); +} + +static off_t handle_telldir(FsContext *ctx, DIR *dir) +{ + return telldir(dir); +} + +static int handle_readdir_r(FsContext *ctx, DIR *dir, struct dirent *entry, + struct dirent **result) +{ + return readdir_r(dir, entry, result); +} + +static void handle_seekdir(FsContext *ctx, DIR *dir, off_t off) +{ + return seekdir(dir, off); +} + +static ssize_t handle_preadv(FsContext *ctx, int fd, const struct iovec *iov, + int iovcnt, off_t offset) +{ +#ifdef CONFIG_PREADV + return preadv(fd, iov, iovcnt, offset); +#else + int err = lseek(fd, offset, SEEK_SET); + if (err == -1) { + return err; + } else { + return readv(fd, iov, iovcnt); + } +#endif +} + +static ssize_t handle_pwritev(FsContext *ctx, int fd, const struct iovec *iov, + int iovcnt, off_t offset) +{ +#ifdef CONFIG_PREADV + return pwritev(fd, iov, iovcnt, offset); +#else + int err = lseek(fd, offset, SEEK_SET); + if (err == -1) { + return err; + } else { + return writev(fd, iov, iovcnt); + } +#endif +} + +static int handle_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)fs_ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK); + if (fd < 0) { + return fd; + } + ret = fchmod(fd, credp->fc_mode); + close(fd); + return ret; +} + +static int handle_mknod(FsContext *fs_ctx, V9fsPath *dir_path, + const char *name, FsCred *credp) +{ + int dirfd, ret; + struct handle_data *data = (struct handle_data *)fs_ctx->private; + + dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH); + if (dirfd < 0) { + return dirfd; + } + ret = mknodat(dirfd, name, credp->fc_mode, credp->fc_rdev); + if (!ret) { + ret = handle_update_file_cred(dirfd, name, credp); + } + close(dirfd); + return ret; +} + +static int handle_mkdir(FsContext *fs_ctx, V9fsPath *dir_path, + const char *name, FsCred *credp) +{ + int dirfd, ret; + struct handle_data *data = (struct handle_data *)fs_ctx->private; + + dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH); + if (dirfd < 0) { + return dirfd; + } + ret = mkdirat(dirfd, name, credp->fc_mode); + if (!ret) { + ret = handle_update_file_cred(dirfd, name, credp); + } + close(dirfd); + return ret; +} + +static int handle_fstat(FsContext *fs_ctx, int fd, struct stat *stbuf) +{ + return fstat(fd, stbuf); +} + +static int handle_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name, + int flags, FsCred *credp) +{ + int ret; + int dirfd, fd; + struct handle_data *data = (struct handle_data *)fs_ctx->private; + + dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH); + if (dirfd < 0) { + return dirfd; + } + fd = openat(dirfd, name, flags | O_NOFOLLOW, credp->fc_mode); + if (fd >= 0) { + ret = handle_update_file_cred(dirfd, name, credp); + if (ret < 0) { + close(fd); + fd = ret; + } + } + close(dirfd); + return fd; +} + + +static int handle_symlink(FsContext *fs_ctx, const char *oldpath, + V9fsPath *dir_path, const char *name, FsCred *credp) +{ + int fd, dirfd, ret; + struct handle_data *data = (struct handle_data *)fs_ctx->private; + + dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH); + if (dirfd < 0) { + return dirfd; + } + ret = symlinkat(oldpath, dirfd, name); + if (!ret) { + fd = openat(dirfd, name, O_PATH | O_NOFOLLOW); + if (fd < 0) { + ret = fd; + goto err_out; + } + ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH); + close(fd); + } +err_out: + close(dirfd); + return ret; +} + +static int handle_link(FsContext *ctx, V9fsPath *oldpath, + V9fsPath *dirpath, const char *name) +{ + int oldfd, newdirfd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + oldfd = open_by_handle(data->mountfd, oldpath->data, O_PATH); + if (oldfd < 0) { + return oldfd; + } + newdirfd = open_by_handle(data->mountfd, dirpath->data, O_PATH); + if (newdirfd < 0) { + close(oldfd); + return newdirfd; + } + ret = linkat(oldfd, "", newdirfd, name, AT_EMPTY_PATH); + close(newdirfd); + close(oldfd); + return ret; +} + +static int handle_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK | O_WRONLY); + if (fd < 0) { + return fd; + } + ret = ftruncate(fd, size); + close(fd); + return ret; +} + +static int handle_rename(FsContext *ctx, const char *oldpath, + const char *newpath) +{ + errno = EOPNOTSUPP; + return -1; +} + +static int handle_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)fs_ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_PATH); + if (fd < 0) { + return fd; + } + ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH); + close(fd); + return ret; +} + +static int handle_utimensat(FsContext *ctx, V9fsPath *fs_path, + const struct timespec *buf) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK); + if (fd < 0) { + return fd; + } + ret = futimens(fd, buf); + close(fd); + return ret; +} + +static int handle_remove(FsContext *ctx, const char *path) +{ + errno = EOPNOTSUPP; + return -1; +} + +static int handle_fsync(FsContext *ctx, int fd, int datasync) +{ + if (datasync) { + return qemu_fdatasync(fd); + } else { + return fsync(fd); + } +} + +static int handle_statfs(FsContext *ctx, V9fsPath *fs_path, + struct statfs *stbuf) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK); + if (fd < 0) { + return fd; + } + ret = fstatfs(fd, stbuf); + close(fd); + return ret; +} + +static ssize_t handle_lgetxattr(FsContext *ctx, V9fsPath *fs_path, + const char *name, void *value, size_t size) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK); + if (fd < 0) { + return fd; + } + ret = fgetxattr(fd, name, value, size); + close(fd); + return ret; +} + +static ssize_t handle_llistxattr(FsContext *ctx, V9fsPath *fs_path, + void *value, size_t size) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK); + if (fd < 0) { + return fd; + } + ret = flistxattr(fd, value, size); + close(fd); + return ret; +} + +static int handle_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name, + void *value, size_t size, int flags) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK); + if (fd < 0) { + return fd; + } + ret = fsetxattr(fd, name, value, size, flags); + close(fd); + return ret; +} + +static int handle_lremovexattr(FsContext *ctx, V9fsPath *fs_path, + const char *name) +{ + int fd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK); + if (fd < 0) { + return fd; + } + ret = fremovexattr(fd, name); + close(fd); + return ret; +} + +static int handle_name_to_path(FsContext *ctx, V9fsPath *dir_path, + const char *name, V9fsPath *target) +{ + char buffer[PATH_MAX]; + struct file_handle *fh; + int dirfd, ret, mnt_id; + struct handle_data *data = (struct handle_data *)ctx->private; + + /* "." and ".." are not allowed */ + if (!strcmp(name, ".") || !strcmp(name, "..")) { + errno = EINVAL; + return -1; + + } + if (dir_path) { + dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH); + } else { + /* relative to export root */ + dirfd = open(rpath(ctx, ".", buffer), O_DIRECTORY); + } + if (dirfd < 0) { + return dirfd; + } + fh = g_malloc(sizeof(struct file_handle) + data->handle_bytes); + fh->handle_bytes = data->handle_bytes; + /* add a "./" at the begining of the path */ + snprintf(buffer, PATH_MAX, "./%s", name); + /* flag = 0 imply don't follow symlink */ + ret = name_to_handle(dirfd, buffer, fh, &mnt_id, 0); + if (!ret) { + target->data = (char *)fh; + target->size = sizeof(struct file_handle) + data->handle_bytes; + } else { + g_free(fh); + } + close(dirfd); + return ret; +} + +static int handle_renameat(FsContext *ctx, V9fsPath *olddir, + const char *old_name, V9fsPath *newdir, + const char *new_name) +{ + int olddirfd, newdirfd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + olddirfd = open_by_handle(data->mountfd, olddir->data, O_PATH); + if (olddirfd < 0) { + return olddirfd; + } + newdirfd = open_by_handle(data->mountfd, newdir->data, O_PATH); + if (newdirfd < 0) { + close(olddirfd); + return newdirfd; + } + ret = renameat(olddirfd, old_name, newdirfd, new_name); + close(newdirfd); + close(olddirfd); + return ret; +} + +static int handle_unlinkat(FsContext *ctx, V9fsPath *dir, + const char *name, int flags) +{ + int dirfd, ret; + struct handle_data *data = (struct handle_data *)ctx->private; + + dirfd = open_by_handle(data->mountfd, dir->data, O_PATH); + if (dirfd < 0) { + return dirfd; + } + + ret = unlinkat(dirfd, name, flags); + close(dirfd); + return ret; +} + +static int handle_init(FsContext *ctx) +{ + int ret, mnt_id; + struct file_handle fh; + struct handle_data *data = g_malloc(sizeof(struct handle_data)); + data->mountfd = open(ctx->fs_root, O_DIRECTORY); + if (data->mountfd < 0) { + ret = data->mountfd; + goto err_out; + } + memset(&fh, 0, sizeof(struct file_handle)); + ret = name_to_handle(data->mountfd, ".", &fh, &mnt_id, 0); + if (ret && errno == EOVERFLOW) { + data->handle_bytes = fh.handle_bytes; + ctx->private = data; + ret = 0; + goto out; + } + /* we got 0 byte handle ? */ + ret = -1; + close(data->mountfd); +err_out: + g_free(data); +out: + return ret; +} + +FileOperations handle_ops = { + .init = handle_init, + .lstat = handle_lstat, + .readlink = handle_readlink, + .close = handle_close, + .closedir = handle_closedir, + .open = handle_open, + .opendir = handle_opendir, + .rewinddir = handle_rewinddir, + .telldir = handle_telldir, + .readdir_r = handle_readdir_r, + .seekdir = handle_seekdir, + .preadv = handle_preadv, + .pwritev = handle_pwritev, + .chmod = handle_chmod, + .mknod = handle_mknod, + .mkdir = handle_mkdir, + .fstat = handle_fstat, + .open2 = handle_open2, + .symlink = handle_symlink, + .link = handle_link, + .truncate = handle_truncate, + .rename = handle_rename, + .chown = handle_chown, + .utimensat = handle_utimensat, + .remove = handle_remove, + .fsync = handle_fsync, + .statfs = handle_statfs, + .lgetxattr = handle_lgetxattr, + .llistxattr = handle_llistxattr, + .lsetxattr = handle_lsetxattr, + .lremovexattr = handle_lremovexattr, + .name_to_path = handle_name_to_path, + .renameat = handle_renameat, + .unlinkat = handle_unlinkat, +}; 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