diff options
Diffstat (limited to 'qemu/hw/9pfs/virtio-9p-proxy.c')
-rw-r--r-- | qemu/hw/9pfs/virtio-9p-proxy.c | 1219 |
1 files changed, 1219 insertions, 0 deletions
diff --git a/qemu/hw/9pfs/virtio-9p-proxy.c b/qemu/hw/9pfs/virtio-9p-proxy.c new file mode 100644 index 000000000..1bc7881f0 --- /dev/null +++ b/qemu/hw/9pfs/virtio-9p-proxy.c @@ -0,0 +1,1219 @@ +/* + * Virtio 9p Proxy callback + * + * Copyright IBM, Corp. 2011 + * + * Authors: + * M. Mohan Kumar <mohan@in.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 <sys/socket.h> +#include <sys/un.h> +#include "hw/virtio/virtio.h" +#include "virtio-9p.h" +#include "qemu/error-report.h" +#include "fsdev/qemu-fsdev.h" +#include "virtio-9p-proxy.h" + +typedef struct V9fsProxy { + int sockfd; + QemuMutex mutex; + struct iovec in_iovec; + struct iovec out_iovec; +} V9fsProxy; + +/* + * Return received file descriptor on success in *status. + * errno is also returned on *status (which will be < 0) + * return < 0 on transport error. + */ +static int v9fs_receivefd(int sockfd, int *status) +{ + struct iovec iov; + struct msghdr msg; + struct cmsghdr *cmsg; + int retval, data, fd; + union MsgControl msg_control; + + iov.iov_base = &data; + iov.iov_len = sizeof(data); + + memset(&msg, 0, sizeof(msg)); + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = &msg_control; + msg.msg_controllen = sizeof(msg_control); + + do { + retval = recvmsg(sockfd, &msg, 0); + } while (retval < 0 && errno == EINTR); + if (retval <= 0) { + return retval; + } + /* + * data is set to V9FS_FD_VALID, if ancillary data is sent. If this + * request doesn't need ancillary data (fd) or an error occurred, + * data is set to negative errno value. + */ + if (data != V9FS_FD_VALID) { + *status = data; + return 0; + } + /* + * File descriptor (fd) is sent in the ancillary data. Check if we + * indeed received it. One of the reasons to fail to receive it is if + * we exceeded the maximum number of file descriptors! + */ + for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) { + if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)) || + cmsg->cmsg_level != SOL_SOCKET || + cmsg->cmsg_type != SCM_RIGHTS) { + continue; + } + fd = *((int *)CMSG_DATA(cmsg)); + *status = fd; + return 0; + } + *status = -ENFILE; /* Ancillary data sent but not received */ + return 0; +} + +static ssize_t socket_read(int sockfd, void *buff, size_t size) +{ + ssize_t retval, total = 0; + + while (size) { + retval = read(sockfd, buff, size); + if (retval == 0) { + return -EIO; + } + if (retval < 0) { + if (errno == EINTR) { + continue; + } + return -errno; + } + size -= retval; + buff += retval; + total += retval; + } + return total; +} + +/* Converts proxy_statfs to VFS statfs structure */ +static void prstatfs_to_statfs(struct statfs *stfs, ProxyStatFS *prstfs) +{ + memset(stfs, 0, sizeof(*stfs)); + stfs->f_type = prstfs->f_type; + stfs->f_bsize = prstfs->f_bsize; + stfs->f_blocks = prstfs->f_blocks; + stfs->f_bfree = prstfs->f_bfree; + stfs->f_bavail = prstfs->f_bavail; + stfs->f_files = prstfs->f_files; + stfs->f_ffree = prstfs->f_ffree; + stfs->f_fsid.__val[0] = prstfs->f_fsid[0] & 0xFFFFFFFFU; + stfs->f_fsid.__val[1] = prstfs->f_fsid[1] >> 32 & 0xFFFFFFFFU; + stfs->f_namelen = prstfs->f_namelen; + stfs->f_frsize = prstfs->f_frsize; +} + +/* Converts proxy_stat structure to VFS stat structure */ +static void prstat_to_stat(struct stat *stbuf, ProxyStat *prstat) +{ + memset(stbuf, 0, sizeof(*stbuf)); + stbuf->st_dev = prstat->st_dev; + stbuf->st_ino = prstat->st_ino; + stbuf->st_nlink = prstat->st_nlink; + stbuf->st_mode = prstat->st_mode; + stbuf->st_uid = prstat->st_uid; + stbuf->st_gid = prstat->st_gid; + stbuf->st_rdev = prstat->st_rdev; + stbuf->st_size = prstat->st_size; + stbuf->st_blksize = prstat->st_blksize; + stbuf->st_blocks = prstat->st_blocks; + stbuf->st_atim.tv_sec = prstat->st_atim_sec; + stbuf->st_atim.tv_nsec = prstat->st_atim_nsec; + stbuf->st_mtime = prstat->st_mtim_sec; + stbuf->st_mtim.tv_nsec = prstat->st_mtim_nsec; + stbuf->st_ctime = prstat->st_ctim_sec; + stbuf->st_ctim.tv_nsec = prstat->st_ctim_nsec; +} + +/* + * Response contains two parts + * {header, data} + * header.type == T_ERROR, data -> -errno + * header.type == T_SUCCESS, data -> response + * size of errno/response is given by header.size + * returns < 0, on transport error. response is + * valid only if status >= 0. + */ +static int v9fs_receive_response(V9fsProxy *proxy, int type, + int *status, void *response) +{ + int retval; + ProxyHeader header; + struct iovec *reply = &proxy->in_iovec; + + *status = 0; + reply->iov_len = 0; + retval = socket_read(proxy->sockfd, reply->iov_base, PROXY_HDR_SZ); + if (retval < 0) { + return retval; + } + reply->iov_len = PROXY_HDR_SZ; + proxy_unmarshal(reply, 0, "dd", &header.type, &header.size); + /* + * if response size > PROXY_MAX_IO_SZ, read the response but ignore it and + * return -ENOBUFS + */ + if (header.size > PROXY_MAX_IO_SZ) { + int count; + while (header.size > 0) { + count = MIN(PROXY_MAX_IO_SZ, header.size); + count = socket_read(proxy->sockfd, reply->iov_base, count); + if (count < 0) { + return count; + } + header.size -= count; + } + *status = -ENOBUFS; + return 0; + } + + retval = socket_read(proxy->sockfd, + reply->iov_base + PROXY_HDR_SZ, header.size); + if (retval < 0) { + return retval; + } + reply->iov_len += header.size; + /* there was an error during processing request */ + if (header.type == T_ERROR) { + int ret; + ret = proxy_unmarshal(reply, PROXY_HDR_SZ, "d", status); + if (ret < 0) { + *status = ret; + } + return 0; + } + + switch (type) { + case T_LSTAT: { + ProxyStat prstat; + retval = proxy_unmarshal(reply, PROXY_HDR_SZ, + "qqqdddqqqqqqqqqq", &prstat.st_dev, + &prstat.st_ino, &prstat.st_nlink, + &prstat.st_mode, &prstat.st_uid, + &prstat.st_gid, &prstat.st_rdev, + &prstat.st_size, &prstat.st_blksize, + &prstat.st_blocks, + &prstat.st_atim_sec, &prstat.st_atim_nsec, + &prstat.st_mtim_sec, &prstat.st_mtim_nsec, + &prstat.st_ctim_sec, &prstat.st_ctim_nsec); + prstat_to_stat(response, &prstat); + break; + } + case T_STATFS: { + ProxyStatFS prstfs; + retval = proxy_unmarshal(reply, PROXY_HDR_SZ, + "qqqqqqqqqqq", &prstfs.f_type, + &prstfs.f_bsize, &prstfs.f_blocks, + &prstfs.f_bfree, &prstfs.f_bavail, + &prstfs.f_files, &prstfs.f_ffree, + &prstfs.f_fsid[0], &prstfs.f_fsid[1], + &prstfs.f_namelen, &prstfs.f_frsize); + prstatfs_to_statfs(response, &prstfs); + break; + } + case T_READLINK: { + V9fsString target; + v9fs_string_init(&target); + retval = proxy_unmarshal(reply, PROXY_HDR_SZ, "s", &target); + strcpy(response, target.data); + v9fs_string_free(&target); + break; + } + case T_LGETXATTR: + case T_LLISTXATTR: { + V9fsString xattr; + v9fs_string_init(&xattr); + retval = proxy_unmarshal(reply, PROXY_HDR_SZ, "s", &xattr); + memcpy(response, xattr.data, xattr.size); + v9fs_string_free(&xattr); + break; + } + case T_GETVERSION: + proxy_unmarshal(reply, PROXY_HDR_SZ, "q", response); + break; + default: + return -1; + } + if (retval < 0) { + *status = retval; + } + return 0; +} + +/* + * return < 0 on transport error. + * *status is valid only if return >= 0 + */ +static int v9fs_receive_status(V9fsProxy *proxy, + struct iovec *reply, int *status) +{ + int retval; + ProxyHeader header; + + *status = 0; + reply->iov_len = 0; + retval = socket_read(proxy->sockfd, reply->iov_base, PROXY_HDR_SZ); + if (retval < 0) { + return retval; + } + reply->iov_len = PROXY_HDR_SZ; + proxy_unmarshal(reply, 0, "dd", &header.type, &header.size); + if (header.size != sizeof(int)) { + *status = -ENOBUFS; + return 0; + } + retval = socket_read(proxy->sockfd, + reply->iov_base + PROXY_HDR_SZ, header.size); + if (retval < 0) { + return retval; + } + reply->iov_len += header.size; + proxy_unmarshal(reply, PROXY_HDR_SZ, "d", status); + return 0; +} + +/* + * Proxy->header and proxy->request written to socket by QEMU process. + * This request read by proxy helper process + * returns 0 on success and -errno on error + */ +static int v9fs_request(V9fsProxy *proxy, int type, + void *response, const char *fmt, ...) +{ + dev_t rdev; + va_list ap; + int size = 0; + int retval = 0; + uint64_t offset; + ProxyHeader header = { 0, 0}; + struct timespec spec[2]; + int flags, mode, uid, gid; + V9fsString *name, *value; + V9fsString *path, *oldpath; + struct iovec *iovec = NULL, *reply = NULL; + + qemu_mutex_lock(&proxy->mutex); + + if (proxy->sockfd == -1) { + retval = -EIO; + goto err_out; + } + iovec = &proxy->out_iovec; + reply = &proxy->in_iovec; + va_start(ap, fmt); + switch (type) { + case T_OPEN: + path = va_arg(ap, V9fsString *); + flags = va_arg(ap, int); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sd", path, flags); + if (retval > 0) { + header.size = retval; + header.type = T_OPEN; + } + break; + case T_CREATE: + path = va_arg(ap, V9fsString *); + flags = va_arg(ap, int); + mode = va_arg(ap, int); + uid = va_arg(ap, int); + gid = va_arg(ap, int); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sdddd", path, + flags, mode, uid, gid); + if (retval > 0) { + header.size = retval; + header.type = T_CREATE; + } + break; + case T_MKNOD: + path = va_arg(ap, V9fsString *); + mode = va_arg(ap, int); + rdev = va_arg(ap, long int); + uid = va_arg(ap, int); + gid = va_arg(ap, int); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ddsdq", + uid, gid, path, mode, rdev); + if (retval > 0) { + header.size = retval; + header.type = T_MKNOD; + } + break; + case T_MKDIR: + path = va_arg(ap, V9fsString *); + mode = va_arg(ap, int); + uid = va_arg(ap, int); + gid = va_arg(ap, int); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ddsd", + uid, gid, path, mode); + if (retval > 0) { + header.size = retval; + header.type = T_MKDIR; + } + break; + case T_SYMLINK: + oldpath = va_arg(ap, V9fsString *); + path = va_arg(ap, V9fsString *); + uid = va_arg(ap, int); + gid = va_arg(ap, int); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ddss", + uid, gid, oldpath, path); + if (retval > 0) { + header.size = retval; + header.type = T_SYMLINK; + } + break; + case T_LINK: + oldpath = va_arg(ap, V9fsString *); + path = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ss", + oldpath, path); + if (retval > 0) { + header.size = retval; + header.type = T_LINK; + } + break; + case T_LSTAT: + path = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "s", path); + if (retval > 0) { + header.size = retval; + header.type = T_LSTAT; + } + break; + case T_READLINK: + path = va_arg(ap, V9fsString *); + size = va_arg(ap, int); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sd", path, size); + if (retval > 0) { + header.size = retval; + header.type = T_READLINK; + } + break; + case T_STATFS: + path = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "s", path); + if (retval > 0) { + header.size = retval; + header.type = T_STATFS; + } + break; + case T_CHMOD: + path = va_arg(ap, V9fsString *); + mode = va_arg(ap, int); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sd", path, mode); + if (retval > 0) { + header.size = retval; + header.type = T_CHMOD; + } + break; + case T_CHOWN: + path = va_arg(ap, V9fsString *); + uid = va_arg(ap, int); + gid = va_arg(ap, int); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sdd", path, uid, gid); + if (retval > 0) { + header.size = retval; + header.type = T_CHOWN; + } + break; + case T_TRUNCATE: + path = va_arg(ap, V9fsString *); + offset = va_arg(ap, uint64_t); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sq", path, offset); + if (retval > 0) { + header.size = retval; + header.type = T_TRUNCATE; + } + break; + case T_UTIME: + path = va_arg(ap, V9fsString *); + spec[0].tv_sec = va_arg(ap, long); + spec[0].tv_nsec = va_arg(ap, long); + spec[1].tv_sec = va_arg(ap, long); + spec[1].tv_nsec = va_arg(ap, long); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sqqqq", path, + spec[0].tv_sec, spec[1].tv_nsec, + spec[1].tv_sec, spec[1].tv_nsec); + if (retval > 0) { + header.size = retval; + header.type = T_UTIME; + } + break; + case T_RENAME: + oldpath = va_arg(ap, V9fsString *); + path = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ss", oldpath, path); + if (retval > 0) { + header.size = retval; + header.type = T_RENAME; + } + break; + case T_REMOVE: + path = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "s", path); + if (retval > 0) { + header.size = retval; + header.type = T_REMOVE; + } + break; + case T_LGETXATTR: + size = va_arg(ap, int); + path = va_arg(ap, V9fsString *); + name = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, + "dss", size, path, name); + if (retval > 0) { + header.size = retval; + header.type = T_LGETXATTR; + } + break; + case T_LLISTXATTR: + size = va_arg(ap, int); + path = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ds", size, path); + if (retval > 0) { + header.size = retval; + header.type = T_LLISTXATTR; + } + 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); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sssdd", + path, name, value, size, flags); + if (retval > 0) { + header.size = retval; + header.type = T_LSETXATTR; + } + break; + case T_LREMOVEXATTR: + path = va_arg(ap, V9fsString *); + name = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ss", path, name); + if (retval > 0) { + header.size = retval; + header.type = T_LREMOVEXATTR; + } + break; + case T_GETVERSION: + path = va_arg(ap, V9fsString *); + retval = proxy_marshal(iovec, PROXY_HDR_SZ, "s", path); + if (retval > 0) { + header.size = retval; + header.type = T_GETVERSION; + } + break; + default: + error_report("Invalid type %d", type); + retval = -EINVAL; + break; + } + va_end(ap); + + if (retval < 0) { + goto err_out; + } + + /* marshal the header details */ + proxy_marshal(iovec, 0, "dd", header.type, header.size); + header.size += PROXY_HDR_SZ; + + retval = qemu_write_full(proxy->sockfd, iovec->iov_base, header.size); + if (retval != header.size) { + goto close_error; + } + + switch (type) { + case T_OPEN: + case T_CREATE: + /* + * A file descriptor is returned as response for + * T_OPEN,T_CREATE on success + */ + if (v9fs_receivefd(proxy->sockfd, &retval) < 0) { + goto close_error; + } + break; + case T_MKNOD: + case T_MKDIR: + case T_SYMLINK: + case T_LINK: + case T_CHMOD: + case T_CHOWN: + case T_RENAME: + case T_TRUNCATE: + case T_UTIME: + case T_REMOVE: + case T_LSETXATTR: + case T_LREMOVEXATTR: + if (v9fs_receive_status(proxy, reply, &retval) < 0) { + goto close_error; + } + break; + case T_LSTAT: + case T_READLINK: + case T_STATFS: + case T_GETVERSION: + if (v9fs_receive_response(proxy, type, &retval, response) < 0) { + goto close_error; + } + break; + case T_LGETXATTR: + case T_LLISTXATTR: + if (!size) { + if (v9fs_receive_status(proxy, reply, &retval) < 0) { + goto close_error; + } + } else { + if (v9fs_receive_response(proxy, type, &retval, response) < 0) { + goto close_error; + } + } + break; + } + +err_out: + qemu_mutex_unlock(&proxy->mutex); + return retval; + +close_error: + close(proxy->sockfd); + proxy->sockfd = -1; + qemu_mutex_unlock(&proxy->mutex); + return -EIO; +} + +static int proxy_lstat(FsContext *fs_ctx, V9fsPath *fs_path, struct stat *stbuf) +{ + int retval; + retval = v9fs_request(fs_ctx->private, T_LSTAT, stbuf, "s", fs_path); + if (retval < 0) { + errno = -retval; + return -1; + } + return retval; +} + +static ssize_t proxy_readlink(FsContext *fs_ctx, V9fsPath *fs_path, + char *buf, size_t bufsz) +{ + int retval; + retval = v9fs_request(fs_ctx->private, T_READLINK, buf, "sd", + fs_path, bufsz); + if (retval < 0) { + errno = -retval; + return -1; + } + return strlen(buf); +} + +static int proxy_close(FsContext *ctx, V9fsFidOpenState *fs) +{ + return close(fs->fd); +} + +static int proxy_closedir(FsContext *ctx, V9fsFidOpenState *fs) +{ + return closedir(fs->dir); +} + +static int proxy_open(FsContext *ctx, V9fsPath *fs_path, + int flags, V9fsFidOpenState *fs) +{ + fs->fd = v9fs_request(ctx->private, T_OPEN, NULL, "sd", fs_path, flags); + if (fs->fd < 0) { + errno = -fs->fd; + fs->fd = -1; + } + return fs->fd; +} + +static int proxy_opendir(FsContext *ctx, + V9fsPath *fs_path, V9fsFidOpenState *fs) +{ + int serrno, fd; + + fs->dir = NULL; + fd = v9fs_request(ctx->private, T_OPEN, NULL, "sd", fs_path, O_DIRECTORY); + if (fd < 0) { + errno = -fd; + return -1; + } + fs->dir = fdopendir(fd); + if (!fs->dir) { + serrno = errno; + close(fd); + errno = serrno; + return -1; + } + return 0; +} + +static void proxy_rewinddir(FsContext *ctx, V9fsFidOpenState *fs) +{ + rewinddir(fs->dir); +} + +static off_t proxy_telldir(FsContext *ctx, V9fsFidOpenState *fs) +{ + return telldir(fs->dir); +} + +static int proxy_readdir_r(FsContext *ctx, V9fsFidOpenState *fs, + struct dirent *entry, + struct dirent **result) +{ + return readdir_r(fs->dir, entry, result); +} + +static void proxy_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off) +{ + seekdir(fs->dir, off); +} + +static ssize_t proxy_preadv(FsContext *ctx, V9fsFidOpenState *fs, + const struct iovec *iov, + int iovcnt, off_t offset) +{ + ssize_t ret; +#ifdef CONFIG_PREADV + ret = preadv(fs->fd, iov, iovcnt, offset); +#else + ret = lseek(fs->fd, offset, SEEK_SET); + if (ret >= 0) { + ret = readv(fs->fd, iov, iovcnt); + } +#endif + return ret; +} + +static ssize_t proxy_pwritev(FsContext *ctx, V9fsFidOpenState *fs, + const struct iovec *iov, + int iovcnt, off_t offset) +{ + ssize_t ret; + +#ifdef CONFIG_PREADV + ret = pwritev(fs->fd, iov, iovcnt, offset); +#else + ret = lseek(fs->fd, offset, SEEK_SET); + if (ret >= 0) { + ret = writev(fs->fd, iov, iovcnt); + } +#endif +#ifdef CONFIG_SYNC_FILE_RANGE + if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) { + /* + * Initiate a writeback. This is not a data integrity sync. + * We want to ensure that we don't leave dirty pages in the cache + * after write when writeout=immediate is sepcified. + */ + sync_file_range(fs->fd, offset, ret, + SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE); + } +#endif + return ret; +} + +static int proxy_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) +{ + int retval; + retval = v9fs_request(fs_ctx->private, T_CHMOD, NULL, "sd", + fs_path, credp->fc_mode); + if (retval < 0) { + errno = -retval; + } + return retval; +} + +static int proxy_mknod(FsContext *fs_ctx, V9fsPath *dir_path, + const char *name, FsCred *credp) +{ + int retval; + V9fsString fullname; + + v9fs_string_init(&fullname); + v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); + + retval = v9fs_request(fs_ctx->private, T_MKNOD, NULL, "sdqdd", + &fullname, credp->fc_mode, credp->fc_rdev, + credp->fc_uid, credp->fc_gid); + v9fs_string_free(&fullname); + if (retval < 0) { + errno = -retval; + retval = -1; + } + return retval; +} + +static int proxy_mkdir(FsContext *fs_ctx, V9fsPath *dir_path, + const char *name, FsCred *credp) +{ + int retval; + V9fsString fullname; + + v9fs_string_init(&fullname); + v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); + + retval = v9fs_request(fs_ctx->private, T_MKDIR, NULL, "sddd", &fullname, + credp->fc_mode, credp->fc_uid, credp->fc_gid); + v9fs_string_free(&fullname); + if (retval < 0) { + errno = -retval; + retval = -1; + } + v9fs_string_free(&fullname); + return retval; +} + +static int proxy_fstat(FsContext *fs_ctx, int fid_type, + V9fsFidOpenState *fs, struct stat *stbuf) +{ + int fd; + + if (fid_type == P9_FID_DIR) { + fd = dirfd(fs->dir); + } else { + fd = fs->fd; + } + return fstat(fd, stbuf); +} + +static int proxy_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name, + int flags, FsCred *credp, V9fsFidOpenState *fs) +{ + V9fsString fullname; + + v9fs_string_init(&fullname); + v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); + + fs->fd = v9fs_request(fs_ctx->private, T_CREATE, NULL, "sdddd", + &fullname, flags, credp->fc_mode, + credp->fc_uid, credp->fc_gid); + v9fs_string_free(&fullname); + if (fs->fd < 0) { + errno = -fs->fd; + fs->fd = -1; + } + return fs->fd; +} + +static int proxy_symlink(FsContext *fs_ctx, const char *oldpath, + V9fsPath *dir_path, const char *name, FsCred *credp) +{ + int retval; + V9fsString fullname, target; + + v9fs_string_init(&fullname); + v9fs_string_init(&target); + + v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); + v9fs_string_sprintf(&target, "%s", oldpath); + + retval = v9fs_request(fs_ctx->private, T_SYMLINK, NULL, "ssdd", + &target, &fullname, credp->fc_uid, credp->fc_gid); + v9fs_string_free(&fullname); + v9fs_string_free(&target); + if (retval < 0) { + errno = -retval; + retval = -1; + } + return retval; +} + +static int proxy_link(FsContext *ctx, V9fsPath *oldpath, + V9fsPath *dirpath, const char *name) +{ + int retval; + V9fsString newpath; + + v9fs_string_init(&newpath); + v9fs_string_sprintf(&newpath, "%s/%s", dirpath->data, name); + + retval = v9fs_request(ctx->private, T_LINK, NULL, "ss", oldpath, &newpath); + v9fs_string_free(&newpath); + if (retval < 0) { + errno = -retval; + retval = -1; + } + return retval; +} + +static int proxy_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size) +{ + int retval; + + retval = v9fs_request(ctx->private, T_TRUNCATE, NULL, "sq", fs_path, size); + if (retval < 0) { + errno = -retval; + return -1; + } + return 0; +} + +static int proxy_rename(FsContext *ctx, const char *oldpath, + const char *newpath) +{ + int retval; + V9fsString oldname, newname; + + v9fs_string_init(&oldname); + v9fs_string_init(&newname); + + v9fs_string_sprintf(&oldname, "%s", oldpath); + v9fs_string_sprintf(&newname, "%s", newpath); + retval = v9fs_request(ctx->private, T_RENAME, NULL, "ss", + &oldname, &newname); + v9fs_string_free(&oldname); + v9fs_string_free(&newname); + if (retval < 0) { + errno = -retval; + } + return retval; +} + +static int proxy_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) +{ + int retval; + retval = v9fs_request(fs_ctx->private, T_CHOWN, NULL, "sdd", + fs_path, credp->fc_uid, credp->fc_gid); + if (retval < 0) { + errno = -retval; + } + return retval; +} + +static int proxy_utimensat(FsContext *s, V9fsPath *fs_path, + const struct timespec *buf) +{ + int retval; + retval = v9fs_request(s->private, T_UTIME, NULL, "sqqqq", + fs_path, + buf[0].tv_sec, buf[0].tv_nsec, + buf[1].tv_sec, buf[1].tv_nsec); + if (retval < 0) { + errno = -retval; + } + return retval; +} + +static int proxy_remove(FsContext *ctx, const char *path) +{ + int retval; + V9fsString name; + v9fs_string_init(&name); + v9fs_string_sprintf(&name, "%s", path); + retval = v9fs_request(ctx->private, T_REMOVE, NULL, "s", &name); + v9fs_string_free(&name); + if (retval < 0) { + errno = -retval; + } + return retval; +} + +static int proxy_fsync(FsContext *ctx, int fid_type, + V9fsFidOpenState *fs, int datasync) +{ + int fd; + + if (fid_type == P9_FID_DIR) { + fd = dirfd(fs->dir); + } else { + fd = fs->fd; + } + + if (datasync) { + return qemu_fdatasync(fd); + } else { + return fsync(fd); + } +} + +static int proxy_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *stbuf) +{ + int retval; + retval = v9fs_request(s->private, T_STATFS, stbuf, "s", fs_path); + if (retval < 0) { + errno = -retval; + return -1; + } + return retval; +} + +static ssize_t proxy_lgetxattr(FsContext *ctx, V9fsPath *fs_path, + const char *name, void *value, size_t size) +{ + 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) +{ + 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) +{ + 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) +{ + 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, + 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 proxy_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 = proxy_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 proxy_unlinkat(FsContext *ctx, V9fsPath *dir, + const char *name, int flags) +{ + int ret; + V9fsString fullname; + v9fs_string_init(&fullname); + + v9fs_string_sprintf(&fullname, "%s/%s", dir->data, name); + ret = proxy_remove(ctx, fullname.data); + v9fs_string_free(&fullname); + + return ret; +} + +static int proxy_ioc_getversion(FsContext *fs_ctx, V9fsPath *path, + mode_t st_mode, uint64_t *st_gen) +{ + int err; + + /* Do not try to open special files like device nodes, fifos etc + * we can get fd for regular files and directories only + */ + if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) { + errno = ENOTTY; + return -1; + } + err = v9fs_request(fs_ctx->private, T_GETVERSION, st_gen, "s", path); + if (err < 0) { + errno = -err; + err = -1; + } + return err; +} + +static int connect_namedsocket(const char *path) +{ + int sockfd, size; + struct sockaddr_un helper; + + if (strlen(path) >= sizeof(helper.sun_path)) { + fprintf(stderr, "Socket name too large\n"); + return -1; + } + sockfd = socket(AF_UNIX, SOCK_STREAM, 0); + if (sockfd < 0) { + fprintf(stderr, "failed to create socket: %s\n", strerror(errno)); + return -1; + } + strcpy(helper.sun_path, path); + helper.sun_family = AF_UNIX; + size = strlen(helper.sun_path) + sizeof(helper.sun_family); + if (connect(sockfd, (struct sockaddr *)&helper, size) < 0) { + fprintf(stderr, "failed to connect to %s: %s\n", path, strerror(errno)); + close(sockfd); + return -1; + } + + /* remove the socket for security reasons */ + unlink(path); + return sockfd; +} + +static int proxy_parse_opts(QemuOpts *opts, struct FsDriverEntry *fs) +{ + const char *socket = qemu_opt_get(opts, "socket"); + const char *sock_fd = qemu_opt_get(opts, "sock_fd"); + + if (!socket && !sock_fd) { + fprintf(stderr, "socket and sock_fd none of the option specified\n"); + return -1; + } + if (socket && sock_fd) { + fprintf(stderr, "Both socket and sock_fd options specified\n"); + return -1; + } + if (socket) { + fs->path = g_strdup(socket); + fs->export_flags = V9FS_PROXY_SOCK_NAME; + } else { + fs->path = g_strdup(sock_fd); + fs->export_flags = V9FS_PROXY_SOCK_FD; + } + return 0; +} + +static int proxy_init(FsContext *ctx) +{ + V9fsProxy *proxy = g_malloc(sizeof(V9fsProxy)); + int sock_id; + + if (ctx->export_flags & V9FS_PROXY_SOCK_NAME) { + sock_id = connect_namedsocket(ctx->fs_root); + } else { + sock_id = atoi(ctx->fs_root); + if (sock_id < 0) { + fprintf(stderr, "socket descriptor not initialized\n"); + } + } + if (sock_id < 0) { + g_free(proxy); + return -1; + } + g_free(ctx->fs_root); + ctx->fs_root = NULL; + + proxy->in_iovec.iov_base = g_malloc(PROXY_MAX_IO_SZ + PROXY_HDR_SZ); + proxy->in_iovec.iov_len = PROXY_MAX_IO_SZ + PROXY_HDR_SZ; + proxy->out_iovec.iov_base = g_malloc(PROXY_MAX_IO_SZ + PROXY_HDR_SZ); + proxy->out_iovec.iov_len = PROXY_MAX_IO_SZ + PROXY_HDR_SZ; + + ctx->private = proxy; + proxy->sockfd = sock_id; + qemu_mutex_init(&proxy->mutex); + + ctx->export_flags |= V9FS_PATHNAME_FSCONTEXT; + ctx->exops.get_st_gen = proxy_ioc_getversion; + return 0; +} + +FileOperations proxy_ops = { + .parse_opts = proxy_parse_opts, + .init = proxy_init, + .lstat = proxy_lstat, + .readlink = proxy_readlink, + .close = proxy_close, + .closedir = proxy_closedir, + .open = proxy_open, + .opendir = proxy_opendir, + .rewinddir = proxy_rewinddir, + .telldir = proxy_telldir, + .readdir_r = proxy_readdir_r, + .seekdir = proxy_seekdir, + .preadv = proxy_preadv, + .pwritev = proxy_pwritev, + .chmod = proxy_chmod, + .mknod = proxy_mknod, + .mkdir = proxy_mkdir, + .fstat = proxy_fstat, + .open2 = proxy_open2, + .symlink = proxy_symlink, + .link = proxy_link, + .truncate = proxy_truncate, + .rename = proxy_rename, + .chown = proxy_chown, + .utimensat = proxy_utimensat, + .remove = proxy_remove, + .fsync = proxy_fsync, + .statfs = proxy_statfs, + .lgetxattr = proxy_lgetxattr, + .llistxattr = proxy_llistxattr, + .lsetxattr = proxy_lsetxattr, + .lremovexattr = proxy_lremovexattr, + .name_to_path = proxy_name_to_path, + .renameat = proxy_renameat, + .unlinkat = proxy_unlinkat, +}; 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